Patent Publication Number: US-11025395-B2

Title: Devices for reporting uplink information

Description:
TECHNICAL FIELD 
     The present disclosure relates generally to communication systems. More specifically, the present disclosure relates to devices for reporting uplink information. 
     BACKGROUND 
     Wireless communication devices have become smaller and more powerful in order to meet consumer needs and to improve portability and convenience. Consumers have become dependent upon wireless communication devices and have come to expect reliable service, expanded areas of coverage and increased functionality. A wireless communication system may provide communication for a number of wireless communication devices, each of which may be serviced by a base station. A base station may be a fixed station that communicates with wireless communication devices. 
     As wireless communication devices have advanced, improvements in communication capacity, speed, flexibility and/or efficiency have been sought. However, improving communication capacity, speed, flexibility and/or efficiency may present certain problems. 
     For example, wireless communication devices may communicate with one or more devices using a communication structure. However, the communication structure used may only offer limited flexibility and/or efficiency. As illustrated by this discussion, systems and methods that improve communication flexibility and/or efficiency may be beneficial. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram illustrating one configuration of one or more evolved Node Bs (eNBs) and one or more user equipments (UEs) in which systems and methods for reporting uplink information with different duplexing configurations may be implemented; 
         FIG. 2  is a flow diagram illustrating one configuration of a method for reporting information on a UE; 
         FIG. 3  is a flow diagram illustrating one configuration of a method for receiving information on an eNB; 
         FIG. 4  is a diagram illustrating one example of a radio frame that may be used in accordance with the systems and methods disclosed herein; 
         FIG. 5  is a diagram illustrating several examples of association regions for uplink reporting in accordance with the systems and methods disclosed herein; 
         FIG. 6  is a diagram illustrating several examples of association regions for uplink reporting in accordance with the systems and methods disclosed herein; 
         FIG. 7  illustrates more specifically the association regions for configuration zero with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 8  illustrates more specifically the association regions for configuration one with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 9  illustrates more specifically the association regions for configuration two with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 10  illustrates more specifically the association regions for configuration three with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 11  illustrates more specifically the association regions for configuration four with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 12  illustrates more specifically the association regions for configuration five with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 13  illustrates more specifically the association regions for configuration six with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 14  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration zero as applied to other configurations; 
         FIG. 15  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration one as applied to other configurations; 
         FIG. 16  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two as applied to other configurations; 
         FIG. 17  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration three as applied to other configurations; 
         FIG. 18  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration four as applied to other configurations; 
         FIG. 19  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration five as applied to other configurations; 
         FIG. 20  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration six as applied to other configurations; 
         FIG. 21  is a diagram illustrating two new superset uplink-downlink (UL-DL) configurations that may be used in accordance with the systems and methods disclosed herein; 
         FIG. 22  illustrates more specifically the association regions for configuration two+three with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 23  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two+three; 
         FIG. 24  is a diagram further illustrating the example set forth in  FIG. 23 ; 
         FIG. 25  illustrates more specifically the association regions for configuration two+four with respect to other uplink-downlink (UL-DL) configurations; 
         FIG. 26  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two+four; 
         FIG. 27  is a diagram further illustrating the example set forth in  FIG. 26 ; 
         FIG. 28  is a flow diagram illustrating one configuration of a method for selecting a reference cell on a UE; 
         FIG. 29  illustrates various components that may be utilized in a user equipment (UE); and 
         FIG. 30  illustrates various components that may be utilized in an evolved Node B (eNB). 
     
    
    
     DETAILED DESCRIPTION 
     A user equipment (UE) for reporting information is described. The UE includes a processor and instructions stored in memory that is in electronic communication with the processor. The UE selects a reference cell having a reference uplink-downlink (UL-DL) configuration. The UE also selects a first uplink subframe from the reference cell. The UE further selects a first subframe set from a first cell having a first UL-DL configuration. The UE additionally determines a first set of associations between the first subframe set and the first uplink subframe. The UE also aggregates information corresponding to the reference cell and information corresponding to the first cell based on the first set of associations to produce aggregated information. The UE further reports the aggregated information on an uplink reporting cell. 
     The aggregated information may include acknowledgment/negative acknowledgment (ACK/NACK) information. 
     The first subframe set may define an association region based on the reference cell. The association region may be the same for all UL-DL configurations. The UE may determine at least one additional set of associations between at least one additional subframe set from the first cell and at least one additional uplink subframe from the reference cell. 
     The first set of associations and the at least one additional set of associations may be balanced between the first uplink subframe and the at least one additional uplink subframe. Determining the first set of associations and determining the at least one additional set of associations may include at least minimizing the distance of each association or minimizing the total distance for all of the associations. 
     Selecting the reference cell may include determining at least one cell with a smallest periodicity. If it is determined that one cell is a cell with a smallest periodicity, then the reference cell may be the cell with the smallest periodicity. The UE may also determines if more than one cell is a cell with a smallest periodicity. If it is determined that more than one cell has the smallest periodicity, then at least one cell with a highest uplink allocation may be determined. If it is determined that one cell is a cell with the highest uplink allocation, then the reference cell may be the cell with the highest uplink allocation. The UE may further determine if more than one cell is a cell with a highest uplink allocation If it is determined that more than one cell has the highest uplink allocation, then a cell with the lowest cell index (Cell_ID) may be determined and the reference cell may be the cell with the lowest cell index (Cell_ID). 
     The uplink reporting cell may be a cell with the lowest cell index (Cell_ID) for a particular uplink subframe. The first cell may be in a first band and the reference cell may be in a second band. The first band and the second band may be different bands. 
     The reference UL-DL configuration may be a superset UL-DL configuration that combines one or more uplink subframes from a PCell and one or more SCells using different UL-DL configurations. The reference UL-DL configuration and the first UL-DL configuration may be the same UL-DL configuration or different UL-DL configurations. 
     A method for reporting information by a user equipment (UE) is also described. The method includes selecting a reference cell having a reference uplink-downlink (UL-DL) configuration. The method also includes selecting a first uplink subframe from the reference cell. The method further includes selecting a first subframe set from a first cell having a first UL-DL configuration. The method additionally includes determining a first set of associations between the first subframe set and the first uplink subframe. The method also includes aggregating information corresponding to the reference cell and information corresponding to the first cell based on the first set of associations to produce aggregated information. The method further includes reporting the aggregated information on an uplink reporting cell. 
     An evolved Node B (eNB) for receiving information is also described. The eNB includes a processor and instructions stored in memory that is in electronic communication with the processor. The eNB determines if aggregated information is being used in connection with a first cell having a first uplink-downlink (UL-DL) configuration and a second cell having a second UL-DL configuration. The first UL-DL configuration is different than the second UL-DL configuration. The eNB also receives aggregated information on an uplink reporting cell. The eNB further de-aggregates the aggregated information based on a set of associations. The uplink reporting cell may be the first cell or the second cell with the lowest cell index (Cell_ID) for each particular uplink subframe. 
     A method for receiving information by an evolved Node B (eNB). The method includes determining if aggregated information is being used in connection with a first cell having a first uplink-downlink (UL-DL) configuration and a second cell having a second UL-DL configuration. The method also includes receiving aggregated information on an uplink reporting cell. The method further includes de-aggregating the aggregated information based on a set of associations. 
     The 3rd Generation Partnership Project, also referred to as “3GPP,” is a collaboration agreement that aims to define globally applicable technical specifications and technical reports for third and fourth generation wireless communication systems. The 3GPP may define specifications for next generation mobile networks, systems, and devices. 
     3GPP Long Term Evolution (LTE) is the name given to a project to improve the Universal Mobile Telecommunications System (UMTS) mobile phone or device standard to cope with future requirements. In one aspect, UMTS has been modified to provide support and specification for the Evolved Universal Terrestrial Radio Access (E-UTRA) and Evolved Universal Terrestrial Radio Access Network (E-UTRAN). 
     At least some aspects of the systems and methods disclosed herein may be described in relation to the 3GPP Long Term Evolution (LTE), LTE-Advanced (LTE-A) and other standards (e.g., 3GPP Releases 8, 9, 10 and/or 11). However, the scope of the present disclosure should not be limited in this regard. At least some aspects of the systems and methods disclosed herein may be utilized in other types of wireless communication systems. 
     A wireless communication device may be an electronic device used to communicate voice and/or data to a base station, which in turn may communicate with a network of devices (e.g., public switched telephone network (PSTN), the Internet, etc.). In describing systems and methods herein, a wireless communication device may alternatively be referred to as a mobile station, a User Equipment (UE), an access terminal, a subscriber station, a mobile terminal, a remote station, a user terminal, a terminal, a subscriber unit, a mobile device, etc. Examples of wireless communication devices include cellular phones, smart phones, personal digital assistants (PDAs), laptop computers, netbooks, e-readers, wireless modems, etc. In 3GPP specifications, a wireless communication device is typically referred to as a User Equipment (UE). However, as the scope of the present disclosure should not be limited to the 3GPP standards, the terms “UE” and “wireless communication device” may be used interchangeably herein to mean the more general term “wireless communication device.” 
     In 3GPP specifications, a base station is typically referred to as a Node B, an evolved or enhanced Node B (eNB), a home enhanced or evolved Node B (HeNB) or some other similar terminology. As the scope of the disclosure should not be limited to 3GPP standards, the terms “base station,” “Node B,” “eNB,” and “HeNB” may be used interchangeably herein to mean the more general term “base station.” Furthermore, the term “base station” may be used to denote an access point. An access point may be an electronic device that provides access to a network (e.g., Local Area Network (LAN), the Internet, etc.) for wireless communication devices. The term “communication device” may be used to denote both a wireless communication device and/or a base station. 
     It should be noted that as used herein, a “cell” may be any communication channel that is specified by standardization or regulatory bodies to be used for International Mobile Telecommunications-Advanced (IMT-Advanced) and all of it or a subset of it may be adopted by 3GPP as licensed bands (e.g., frequency band) to be used for communication between a Node B (e.g., eNodeB) and a UE. “Configured cells” are those cells of which the UE is aware and is allowed by a Node B (e.g., eNB) to transmit or receive information. “Configured cell(s)” may be serving cell(s). The UE may receive system information and perform the required measurements on all configured cells. “Activated cells” are those configured cells on which the UE is transmitting and receiving. That is, activated cells are those cells for which the UE monitors the physical downlink control channel (PDCCH) and in the case of a downlink transmission, those cells for which the UE decodes a physical downlink shared channel (PDCCH). “Deactivated cells” are those configured cells that the UE is not monitoring the transmission PDCCH. It should be noted that a “cell” may be described in terms of differing dimensions. For example, a “cell” may have temporal, spatial (e.g., geographical) and frequency characteristics. 
     In 3GPP specifications, carrier aggregation typically refers to the concurrent utilization of more than one carrier. In one example, carrier aggregation may be used to increase the effective bandwidth available to a UE. One type of carrier aggregation is inter-band carrier aggregation. In inter-band carrier aggregation, multiple carriers from multiple bands may be aggregated. For example, a carrier in a first band (e.g., 800 MHz) may be aggregated with a carrier in a second band (e.g., 2.6 GHz). 
     In the carrier aggregation enhancement, different time division duplex (TDD) uplink-downlink (UL-DL) configurations may be used for inter-band aggregation (e.g., the cells or component carriers (CCs) in different bands may have different UL-DL configurations). Carrier aggregation with different TDD configurations may be referred to as inter-band carrier aggregation. 
     For inter-band carrier aggregation, full-duplex may be supported so that a UE can simultaneously transmit on one cell in one band, and receive on another cell in another band. With full duplex support, the uplink scheduling and uplink transmission may be performed independently on each band. The acknowledgement/negative acknowledgement (ACK/NACK) feedback on the physical hybrid automatic repeat request (ARQ) indication channel (PHICH) or the physical downlink control channel (PDCCH) can also be handled by each carrier. However, in the current specification (e.g., 3GPP Release 10), the uplink reporting is carried only on the primary cell (PCell). This may or may not be changed in the future (e.g., in 3GPP Release 11). Under the current specification (e.g., 3GPP Release 10) for inter-band carrier aggregation with different UL-DL configurations, the uplink reporting of a secondary cell (SCell) with a different UL-DL configuration may be dropped. Therefore, some new rules of aggregating and reporting of ACK/NACK for downlink transmission need to be defined for inter-band carrier aggregation with different TDD UL-DL configurations. 
     The systems and methods disclosed herein may be used for uplink reporting when different UL-DL configurations are used in different cells. Furthermore, the systems and methods disclosed herein may be used to multiplex and aggregate uplink control information (UCI) reports from multiple cells in different bands to one uplink reporting on a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). One example of UCI may be ACK/NACK reporting (e.g., ACK/NACK bits). 
     The systems and methods disclosed herein may be used to select uplink subframes in cells for uplink reporting. The systems and methods disclosed herein may also be used for ACK/NACK multiplexing and reporting based on subframe region mapping. The systems and methods disclosed herein may additionally be used for ACK/NACK multiplexing and reporting based on PCell uplink configuration. The systems and methods disclosed herein may also be used for ACK/NACK multiplexing and reporting based on the cell with maximum uplink allocation. The systems and methods disclosed herein may additionally be used for ACK/NACK multiplexing and reporting based on a cell with the aggregated uplink allocation of multiple (e.g., some, all) cells. 
     To achieve different downlink and uplink traffic ratios, seven UL-DL configurations are specified in 3GPP specifications (e.g., 3GPP TS 36.211). These allocations can allocate between 40% and 90% of subframes to downlink signals. 
     It should be noted that a subframe association may be referred to as an “uplink-downlink association,” which may include uplink-to-downlink subframe associations and/or downlink-to-uplink subframe associations. Examples of associations include association of a downlink subframe physical downlink control channel (PDCCH) to uplink power control in an uplink subframe, association of a downlink subframe physical downlink control channel (PDCCH) to physical uplink shared channel (PUSCH) allocation in an uplink subframe, associations of acknowledgement and negative acknowledgement (ACK/NACK) feedback on uplink subframe(s) for physical downlink shared channel (PDCCH) transmissions in downlink subframe(s), association of acknowledgement and negative acknowledgement (ACK/NACK) feedback on a physical hybrid automatic repeat request (HARQ) indicator channel (PHICH) or physical downlink control channel (PDCCH) for physical uplink shared channel (PUSCH) transmission(s) in uplink subframe(s), etc. 
     The LTE-TDD frame structure and the uplink-downlink configuration may be given in 3GPP TS 36.211 [1]. Uplink-downlink configurations with both 5 millisecond (ms) and 10 ms downlink-to-uplink switch-point periodicity may be supported. In current LTE TDD systems, there are seven UL-DL configurations (e.g., configurations 0-6) that are specified in the standard. 
     Configuration zero (e.g., “0”) is a 5 ms configuration with an allocation of six uplink (UL) subframes (which may be a current maximum allocation for UL subframes). An illustration of two radio frames of configuration 0 is provided in Table 1 below. In the Tables given hereafter, “D” denotes a downlink subframe, “U” denotes an uplink subframe and “S” denotes a special subframe. 
     
       
         
           
               
               
             
               
                   
                 TABLE (1) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 U 
               
               
                   
               
            
           
         
       
     
     Configuration one (e.g., “1”) is a 5 ms configuration with 4 UL subframes. An illustration of two radio frames of configuration 1 is provided in Table 2 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (2) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 S 
                 U 
                 U 
                 D 
               
               
                   
               
            
           
         
       
     
     Configuration two (e.g., “2”) is a 5 ms configuration with 2 UL subframes. An illustration of two radio frames of configuration 2 is provided in Table 3 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (3) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 S 
                 U 
                 D 
                 D 
               
               
                   
               
            
           
         
       
     
     Configuration three (e.g., “3”) is a 10 ms configuration with 3 UL subframes (which may be the maximum number of uplink subframes for current 10 ms configurations). An illustration of two radio frames of configuration 3 is provided in Table 4 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (4) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                   
               
            
           
         
       
     
     Configuration four (e.g., “4”) is a 10 ms configuration with 2 UL subframes. An illustration of two radio frames of configuration 4 is provided in Table 5 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (5) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                   
               
            
           
         
       
     
     Configuration five (e.g., “5”) is a 10 ms configuration with 1 UL subframe. An illustration of two radio frames of configuration 5 is provided in Table 6 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (6) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                   
               
            
           
         
       
     
     Configuration six (e.g., “6”) is a 5 ms configuration with 5 UL subframes. An illustration of two radio frames of configuration 6 is provided in Table 7 below. 
     
       
         
           
               
               
             
               
                   
                 TABLE (7) 
               
             
            
               
                   
                   
               
               
                   
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                   
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
                   
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Subframe Type 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 D 
               
               
                   
               
            
           
         
       
     
     Examples of associations (in LTE-TDD, for instance) include the association of a PDCCH for uplink power control of an uplink subframe, association of a PDCCH for physical uplink shared channel (PUSCH) allocation in an uplink subframe, associations of ACK/NACK feedback of downlink transmission on uplink subframe(s), ACK/NACK feedback of uplink transmission on PHICH or PDCCH, etc. 
     For clarity, one example of a frame structure that may be used in accordance with the systems and methods disclosed herein is given from 3GPP TS 36.211 as follows. This frame structure may be applicable in time-division duplexing (TDD) approaches. Each frame may have a length of T f =307200·T s =10 milliseconds (ms), where T f  is a radio frame duration and T s  is a time unit equal to 
             1     (     15000   ×   2048     )           
seconds. The frame may include two half-frames, each having a length of 153600·T s =5 ms. Each half-frame may include five subframes, each having a length of 30720·T s =1 ms. Some UL-DL frame configurations are illustrated in Table 8 below.
 
     
       
         
           
               
               
               
             
               
                 TABLE (8) 
               
             
            
               
                   
               
               
                 UL-DL 
                   
                   
               
               
                 Configuration 
                 Downlink-to-Uplink 
                 Subframe Number 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Number 
                 Switch-Point Periodicity 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 0 
                 5 ms 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 U 
               
               
                 1 
                 5 ms 
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 S 
                 U 
                 U 
                 D 
               
               
                 2 
                 5 ms 
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 S 
                 U 
                 D 
                 D 
               
               
                 3 
                 10 ms  
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 4 
                 10 ms  
                 D 
                 S 
                 U 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 5 
                 10 ms  
                 D 
                 S 
                 U 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
                 D 
               
               
                 6 
                 5 ms 
                 D 
                 S 
                 U 
                 U 
                 U 
                 D 
                 S 
                 U 
                 U 
                 D 
               
               
                   
               
            
           
         
       
     
     In Table 8, for each subframe in a radio frame, “D” indicates that the subframe is reserved for downlink transmissions, “U” indicates that the subframe is reserved for uplink transmissions and “S” indicates a special subframe with three fields: a downlink pilot time slot (DwPTS), a guard period (GP) and an uplink pilot time slot (UpPTS). The length of DwPTS and UpPTS is given in Table 9 (from Table 4.2-1 of 3GPP TS 36.211) subject to the total length of DwPTS, GP and UpPTS being equal to 30720·T s =1 ms. Table 9 illustrates several configurations of (standard) special subframes. Each subframe i is defined as two slots, 2i and 2i+1 of length T slot =15360·T s =0.5 ms in each subframe. In Table 9, “cyclic prefix” is abbreviated as “CP” and “configuration” is abbreviated as “Config” for convenience. 
     
       
         
           
               
               
               
             
               
                   
                 TABLE (9) 
               
             
            
               
                   
                   
               
               
                   
                 Normal CP in downlink 
                 Extended CP in downlink 
               
            
           
           
               
               
               
               
            
               
                   
                 UpPTS 
                   
                 UpPTS 
               
            
           
           
               
               
               
               
               
               
               
            
               
                 Special 
                   
                 Normal 
                 Extended 
                   
                 Normal 
                 Extended 
               
               
                 Subframe 
                   
                 CP in 
                 CP in 
                   
                 CP in 
                 CP in 
               
               
                 Config 
                 DwPTS 
                 uplink 
                 uplink 
                 DwPTS 
                 uplink 
                 uplink 
               
               
                   
               
               
                 0 
                  6592 · T s   
                 2192 · T s   
                 2560 · T s   
                  7680 · T s   
                 2192 · T s   
                 2560 · T s   
               
               
                 1 
                 19760 · T s   
                   
                   
                 20480 · T s   
               
               
                 2 
                 21952 · T s   
                   
                   
                 23040 · T s   
               
               
                 3 
                 24144 · T s   
                   
                   
                 25600 · T s   
               
               
                 4 
                 26336 · T s   
                   
                   
                  7680 · T s   
                 4384 · T s   
                 5120 · T s   
               
               
                 5 
                  6592 · T s   
                 4384 · T s   
                 5120 · T s   
                 20480 · T s   
               
               
                 6 
                 19760 · T s   
                   
                   
                 23040 · T s   
               
               
                 7 
                 21952 · T s   
                   
                   
                 — 
                 — 
                 — 
               
               
                 8 
                 24144 · T s   
                   
                   
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     UL-DL configurations with both 5 ms and 10 ms downlink-to-uplink switch-point periodicity are supported. In the case of 5 ms downlink-to-uplink switch-point periodicity, the special subframe exists in both half-frames. In the case of 10 ms downlink-to-uplink switch-point periodicity, the special subframe exists in the first half-frame only. Subframes 0 and 5 and DwPTS may be reserved for downlink transmission. UpPTS and the subframe immediately following the special subframe may be reserved for uplink transmission. In case multiple cells are aggregated, a UE may assume the same UL-DL configuration across all the cells and that the guard period of the special subframe in the different cells have an overlap of at least 1456·T s . 
     The UL-DL configuration may be a part of a SystemInformationBlockType1 (SIB1), defined by an information element (IE) TDD-Config, which includes a subframe assignment and specialSubframePatterns. The SIB1 may be transmitted on a broadcast control channel as a logical channel. 
     In the current specification (e.g., 3GPP Release 10) for carrier aggregation, the same TDD UL-DL configuration may be required for all aggregated cells. Additionally, the TDD UL-DL configuration may only be obtained from a PCell. As given in TS 36.331 Section 5.2.2.1 [3]:
         “The UE applies the system information acquisition and change monitoring procedures for the PCell only. For SCells, E-UTRAN provides, via dedicated signaling, all system information relevant for operation in RRC_CONNECTED when adding the SCell. Upon change of the relevant system information of a configured SCell, E-UTRAN releases and subsequently adds the concerned SCell, which may be done with a single RRCConnectionReconfiguration message.
           E-UTRAN may configure via dedicated signaling different parameter values than the ones broadcast in the concerned SCell.”   
               

     Support for different TDD UL-DL configurations on different bands is considered in 3GPP discussion of carrier aggregation enhancement. The carrier aggregation with different TDD configurations may also be called inter-band carrier aggregation. The carrier aggregation in a heterogeneous network scenario is the key incentive for different TDD UL-DL configurations. With a heterogeneous network, a pico-cell in one band may have a very different UL-DL traffic load than a macro-cell in another band. Such a situation may require different UL-DL configurations. The PCell may be configured with the marco-cell or the pico-cell. 
     In one configuration of carrier aggregation, it may be assumed that the same eNB scheduler manages the resource for the PCell and SCell(s). Thus, the scheduler may know the actual configuration of each cell. The UEs may also be informed of the actual UL-DL configuration of each aggregated cell. This may especially be the case if the UE has a different UL-DL configuration from the PCell. 
     In a 3GPP specification meeting (e.g., RAN1 #66), it was agreed that: “If Support of different TDD UL-DL configurations on different bands is specified, the UEs will be informed of the actual UL/DL configuration of each aggregated CC. Note that depending on how the Rel-10 signaling is modified, it should be ensured that CCs in the same band have the same configuration. [5]” Also, it was agreed (e.g., RAN1 #66) that no new UL-DL configuration should be introduced. 
     Two methods may be used to get the UL-DL configuration of an SCell on a different band from the PCell. One method is to reuse existing dedicated signaling. For example, for SCells in a different band, E-UTRAN provides, via dedicated signaling, all system information relevant for operation in RRC_CONNECTED when adding the SCell. Upon change of the relevant system information of a configured SCell, E-UTRAN may release and may subsequently add the concerned SCell, which may be done with a single RRCConnectionReconfiguration message. In another method, when an SCell in a different band is added, the UE may be setup with an anchor cell, or a special SCell, or a secondary PCell, or a band PCell, in the band, and may obtain the system information from the PSS/SSS and BCH of each band. This may require more monitoring by the UE. 
     For inter-band carrier aggregation, each band may have its own power amplifier and filter. Thus, full duplex may be supported for simultaneous transmission on a cell in one band and reception on another cell in a different band. 
     There are four basic functions in uplink and downlink associations. Details can be found in TS36.213 [2]. Downlink transmission and scheduling: PDSCH allocation is provided in the PDCCH and PDSCH transmission is performed in the same subframe. Uplink transmission scheduling or uplink grant: the UE shall upon detection of a PDCCH with uplink DCI format and/or a PHICH transmission in subframe n intended for the UE, adjust the corresponding PUSCH transmission in subframe n+k, with k given in Table 8-2 of TS 36.213, according to the PDCCH and PHICH information. Downlink ACK/NACK feedback for uplink transmissions: for PUSCH transmissions scheduled from serving cell c in subframe n, a UE shall determine the corresponding PHICH resource of serving cell c in subframe n+k PHICH , where k PHICH  is given in Table 9.1.2-1 of TS 36.213 for TDD. Alternatively, the PDCCH can override PHICH by indicating a new uplink grant with new data transmission or retransmission. Uplink ACK/NACK feedback for downlink transmissions: the ACK/NACK bits from a downlink association set are reported on PUCCH or PUSCH if PUSCH is allocated for the UE in the uplink subframe. The downlink association set depends on the TDD UL-DL configuration, as given in Table 10.1.3.1-1 of TS 36.213, which is given as Table 10 below. In Release-10 with carrier aggregation, the ACK/NACK bits of multiple serving cells are multiplexed and/or bundled, and reported on the PCell only with PUCCH or PUSCH transmission. 
     
       
         
           
               
               
             
               
                 TABLE (10) 
               
             
            
               
                   
               
               
                 UL-DL 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Configuration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 0 
                 — 
                 — 
                 6 
                 — 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                 1 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
               
               
                 2 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6, 11 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 12, 8, 7, 11 
                 6, 5, 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 13, 12, 9, 8, 7, 5, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 4, 11, 6 
               
               
                 6 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                   
               
            
           
         
       
     
     With full-duplex support, the uplink scheduling and uplink transmission may be performed independently on each band. The ACK/NACK feedback on PHICH or PDCCH can also be handled by each carrier. Since different configurations have different uplink scheduling associations, cross-carrier scheduling for uplink transmissions may be disabled. However, cross-carrier scheduling for downlink transmissions may be used in a subframe where both cells have a downlink allocation. Furthermore, uplink scheduling may also be used if the association rules are defined so that there is no conflict with existing per cell based scheduling. In one configuration, all downlink signaling and PUSCH and PDSCH transmissions may be handled with full-duplex support for inter-band carrier aggregation with different UL-DL configurations. 
     However, in the Release-10 specification, the uplink reporting may be carried only on the PCell. For inter-band carrier aggregation with different UL-DL configurations, the uplink reporting of an SCell with a different UL-DL configuration may be dropped if the PCell has a downlink allocation and the SCell has an uplink allocation in the subframe. Conversely, in a subframe where a PCell is configured with an uplink and an SCell is configured with a downlink allocation, the ACK/NACK from the SCell may not be reported on the PCell because there is no uplink association for the ACK/NACK transmission in the SCell for the given subframe. 
     Similarly, the PUCCH and PUSCH are also used for feedback of channel state information (CSI). In Release-10, CSI reporting is scheduled independently for each cell, but only the PCell may carry the CSI reporting. Thus, a collision between an ACK/NACK and the CSI reporting may occur. With full-duplex support, several approaches may be considered to solve the uplink reporting problem. 
     Approach 1: In one approach, each band may have an anchor cell (e.g., the PCell in one band, an SCell in a different band may perform as a special SCell (SSCell), secondary PCell (SPCell) or primary secondary cell (PSCell) for the given band). Thus, the ACK/NACK reporting on PUCCH or PUSCH may be done on the SSCell, SPCell or PSCell for all the serving cells of each band. Since all the serving cells in a band have the same UL-DL configuration, there is no conflict in existing UL-DL associations. However, this approach requires multiple PUCCH or PUSCH reporting if inter-band aggregation is used. Even if the same UL-DL configuration is used in different bands, multiple PUCCH or PUSCH reporting are needed. 
     Approach 2: In another approach, each group of cells with the same UL-DL configuration may have an anchor cell (e.g., the PCell in one group, an SCell in a different band with a different UL-DL configuration may perform as an SSCell, SPCell or PSCell for the given UL-DL configuration group). Thus, the ACK/NACK reporting on PUCCH or PUSCH may be performed for each UL-DL configuration group. Note a UL-DL configuration group may include cells in different bands if they have the same UL-DL configuration. Since all serving cells in a group have the same UL-DL configuration, there is no conflict in existing UL-DL associations. Again, this approach requires multiple PUCCH or PUSCH reporting if inter-band aggregation with different UL-DL configurations is used. 
     Approach 3: In another approach, the PUCCH or PUSCH reporting of ACK/NACK and CSI may be carried on a PCell only. This is consistent with the current specification (e.g., 3GPP Release-10). For inter-band carrier aggregation with different UL-DL configurations, the uplink reporting of an SCell with a different UL-DL configuration may not be able to transmit if the PCell has a downlink allocation and the SCell has an uplink allocation in the subframe. Therefore, some new rules of aggregating and reporting of ACK/NACK for downlink transmission may need to be defined for inter-band carrier aggregation with different UL-DL configurations. 
     Approach 4: In yet another approach, PUCCH or PUSCH reporting may be carried on a serving cell. The serving cell may be the PCell, an SCell or a combination of uplink subframes in the PCell and SCell(s). For example, the serving cell may be a PCell for a first uplink subframe and may be an SCell for a second uplink subframe (with the first uplink subframe and the second uplink subframe occurring in the same radio frame, for example). Again, some new rules of aggregating and reporting of ACK/NACK for downlink transmission may need to be defined for inter-band carrier aggregation with different UL-DL configurations. 
     In many cases, the ACK/NACK bits of each cell depend on the actual PDSCH transmissions of the cell. If no PDSCH transmission is scheduled for a UE on a cell, there may be no ACK/NACK feedback on uplink reports for the given cell. If there are ACK/NACK bits to be reported on a cell, the rules of report association may need to be defined for the cell if it has a different configuration from the reporting reference configuration (e.g., the PCell configuration). 
     The systems and methods described herein may be directed to the uplink ACK/NACK multiplexing and reporting indicated in approach 3 and approach 4. In particular, an approach on how to aggregate the ACK/NACK bits for downlink transmissions on cells with different TDD UL-DL configurations is described. 
     With approach 3, PUCCH or PUSCH reporting may be carried on the PCell only. When an SCell has a different configuration from the PCell, the ACK/NACK reporting of downlink transmissions may have different associations. Thus, ACK/NACK from different subframe indexes in the SCell and the PCell may be associated to the same uplink subframe in both the PCell and the SCell. Furthermore, there may be cases where a subframe is configured with downlink in the PCell and an uplink in the SCell. Thus, the ACK/NACK associated in an SCell cannot be reported in the PCell if the existing SCell associations are used. Thus, new rules may need to be developed to aggregate the ACK/NACK bits for downlink transmissions on cells with different UL-DL allocations. 
     In one association mapping approach, the same association mapping can be applied to all UL-DL configurations. For example, an association region for each UL-DL configuration may be defined for the uplink reporting of different UL-DL configurations. The association region may be derived from the reference configuration. 
     In the case of PCell-only reporting, the reference configuration may be the PCell configuration. Thus, the applied association region may keep the same ACK/NACK associations for the PCell. The association region may add possible downlink transmission associations from different UL-DL configurations on the SCells and may associate then to the uplink subframes of the PCell. For an SCell, the ACK/NACK bits of the SCell in each association region is obtained and reported on the associated uplink in the PCell. 
     The approach may have many advantages. For example, this approach may be beneficial because it may provide simple and unified association mappings based on the reference configuration. This approach may also be beneficial because the fixed cells for uplink reporting may allow for backwards compatibility. Additionally, this approach may be beneficial because there may be no mapping changes with an SCell activation (e.g., adding an SCell) or deactivation (e.g., removing an SCell). Furthermore, this approach may be beneficial because there may be no mapping change with an SCell re-configuration (e.g., change in UL-DL configuration of the SCell). 
     The modified downlink association set index is given in Table 11 below. The new, added associations are included in parentheses and are added to the end of existing associations of the reference cell UL-DL configuration, i.e., the PCell in this case. Thus, for the PCell, the association may be the same as in the current specification (e.g., 3GPP Releases 8, 9 and 10). The added associations may not apply for the PCell reporting and the ordering of ACK/NACK bits may follow the existing rules. The added associations may apply for the reporting of an SCell. On the other hand, some of the existing associations from the PCell may not apply to an SCell. Therefore, the ACK/NACK bits for an SCell may remove the bits that are not applicable to the SCell configuration and may include the bits in the added associations that are applicable. The ACK/NACK bits ordering may follow the given set index order in Table 11. 
     
       
         
           
               
               
             
               
                 TABLE (11) 
               
             
            
               
                   
               
               
                 Reference 
                   
               
               
                 Cell 
               
               
                 UL-DL 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Configuration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 0 
                 — 
                 — 
                 6, (5) 
                 (5, 4) 
                 4 
                 — 
                 — 
                 6 
                 (5, 4) 
                 4 
               
               
                 1 
                 — 
                 — 
                 7, 6 
                 4, (6, 5) 
                 — 
                 — 
                 — 
                 7, 6 
                 4, (5) 
                 — 
               
               
                 2 
                 — 
                 — 
                 8, 7, 4, 6, (5) 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6, 11, (9, 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 8) 
               
               
                 4 
                 — 
                 — 
                 12, 8, 7, 11, 
                 6, 5, 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 (9) 
               
               
                 5 
                 — 
                 — 
                 13, 12, 9, 8, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 7, 5, 4, 11, 6 
               
               
                 6 
                 — 
                 — 
                 7 
                 7, (6) 
                 5, 
                 — 
                 — 
                 7 
                 7, (5, 
                 — 
               
               
                   
                   
                   
                   
                   
                 (6) 
                   
                   
                   
                 4) 
               
               
                   
               
            
           
         
       
     
     The ACK/NACK reporting on the PCell may be the aggregated ACK/NACK bits of the PCell and the SCell(s). The ACK/NACK aggregation may be performed by multiplexing the ACK/NACK bits of each serving cell by cell ordering (e.g., by cell index (Cell_ID)). Since the PCell has a cell index (Cell_ID) of 0, ACK/NACK bits of the PCell may be at the beginning. The ACK/NACK bits of the SCell(s) may be appended based on the cell ordering of each cell. For example, the ACK/NACK bits of an SCell with a lower Cell_ID may be appended before the ACK/NACK bits of an SCell with a higher Cell_ID. The ACK/NACK bundling of each cell and/or cross cell may or may not be applied depending on the configuration or the signaling. 
     In this approach, the PCell may be the most important cell for a UE. The UE may camp on and obtain system information from the PCell. The PCell-only solution may simplify the UE monitoring. The proposed ACK/NACK association approach may unify the ACK/NACK mappings. Thus, the ACK/NACK bits of all the cells may be distributed into the uplink reporting on the PCell. 
     This approach may be beneficial because of the simplicity of the uplink monitoring, the backwards compatibility and the ability to maintain the same uplink reporting agreement. This approach may also be beneficial because the PCell and the SCell(s) may have arbitrary UL-DL configurations. 
     In some cases, the network may limit the possible combinations of UL-DL configurations. In one case, the PCell should always have the same or smaller periodicity than the SCell. Therefore, if the PCell has 5 ms periodicity, then an SCell may have 5 ms or 10 ms periodicity. However, if the PCell has 10 ms periodicity, then an SCell may also have 10 ms periodicity. In another case, the PCell and the SCell(s) should always use the same periodicity setting. 
     The use of an association region based on a reference cell (e.g., the PCell) may provide a simple mapping approach to gathering uplink ACK/NACK report bits from other cells with different UL-DL configurations. However, the use of an association region may provide unbalanced distribution of ACK/NACK bits into different uplink subframes. For example, if a PCell has UL-DL configuration 3 and an SCell has UL-DL configuration 2, then the number of ACK/NACK bits mapped from the SCell are 5, 1 and 2 for the uplink subframes 2, 3 and 4 respectively. In some cases, a network may have difficulties handling unbalanced ACK/NACK bit distributions. 
     In another association mapping approach, the association mapping for a cell may be based on the number of uplink subframes in the reference cell. In one configuration, the reference cell may be the PCell. The mapping rules for a given configuration may include distributing the ACK/NACK bits into the uplink subframes of the reference cell configuration as evenly (e.g., as balanced) as possible. The mapping rules for a given configuration may also include putting the ACK/NACK bit for a special subframe at the end of the mapped ACK/NACK bits on each uplink subframe. This may be because the special subframe may have less downlink allocation, and may likely not be used for PDSCH transmission. The mapping rules for a given configuration may additionally include requiring that the distance between a downlink transmission and the corresponding uplink ACK/NACK report is at least 4 milliseconds (e.g., 4 subframes). 
     The association mapping may be improved (e.g., “optimized”) by minimizing the total mapping distance for all downlink transmission to uplink mappings. The association mapping may also be improved (e.g., “optimized”) by minimizing the mapping distance for the associations (e.g., for each association). In some cases, this may lead to longer mapping distances for some other associations. 
     The mapping of each UL-DL configuration with different reference configurations may be provided by or illustrated in new association tables. There may be many possible combinations for the associations. In one configuration, the associations from the regional mapping above may be reused as much as possible. In such a configuration, only the configurations with very unevenly distributed bits may be redefined. However, no matter what association table is used, the principle of defining fixed associations based on the reference cell UL-DL configuration may remain the same. Therefore, the association table may be agreed upon and specified in a standard (e.g., 3GPP Release 11). In this approach, the new associations may distribute the ACK/NACK bits more evenly in all of the uplink mapping subframes based on reference cell configuration. 
     In approach 4 above, the PUCCH or PUSCH reporting may be carried on one serving cell only in any subframe number. The serving cell may be the PCell, SCell or a combination the PCell and the SCell(s). For example, the serving cell may be the PCell for one uplink subframe and an SCell for another uplink subframe. The reporting may be carried on the uplink subframe of the serving cell regardless of whether the serving cell is a PCell or an SCell for a given uplink subframe. 
     In one approach, a combination of uplink subframes in the PCell and SCell(s) may be used. In this approach, the uplink reporting association may exist if any serving cell has an uplink allocation in a given subframe. The uplink reporting cell may be decided based on the order of the cell index (Cell_ID) for each uplink subframe. The PCell may always have the lowest Cell_ID (e.g., 0). In a subframe with the uplink subframe in the PCell, the uplink control information (UCI) may be reported on the PUCCH or PUSCH of the PCell (because it has the lowest Cell_ID, for example). In a subframe with a downlink subframe in the PCell and an uplink subframe in one or more of the SCells, the UCI may be reported on the PUCCH or PUSCH of an SCell. In the case of multiple SCells that have uplink subframes in the same subframe, the uplink subframe in the SCell with the lowest cell index (Cell_ID) may be used. Thus, the serving cell actually defines a superset UL-DL configuration of combined UL-DL configuration(s). For example, the superset UL-DL configuration may have an uplink allocation if any cell in the subframe has an uplink subframe. Again, some new rules of aggregating and reporting of ACK/NACK for downlink transmission may need to be defined for inter-band carrier aggregation with different UL-DL configurations. 
     In one configuration, the ACK/NACK aggregation may let each cell maintain the same associations (e.g., as in 3GPP Releases 8, 9 and 10). In one instance, the ACK/NACK bits of all cells with an uplink subframe are multiplexed together based on Cell_ID ordering. The aggregated ACK/NACK bits may be reported on the uplink subframe of the selected cell (e.g., the uplink reporting cell). This approach may have the benefit of backwards compatibility for uplink ACK/NACK reporting associations. A possible drawback of this approach is the variable payload size of the ACK/NACK report in different uplink subframes. For example, in a subframe where only one cell may have an uplink allocation, the ACK/NACK bits of only one cell are carried in the PUCCH or PUSCH UCI report. However, in a subframe where multiple cells have uplink allocation, the ACK/NACK bits of these cells may be aggregated and carried in the PUCCH or PUSCH UCI report on the one selected cell. Thus, a significantly larger payload may result for multiple cells with an ACK/NACK payload than with a single cell with an ACK/NACK payload. The high variation of ACK/NACK payloads in different uplink subframes may lead to high variation of ACK/NACK performance. As a result, the network may have to be designed so that the performance of the ACK/NACK reporting with the highest payload can be satisfied. This may inevitably reduce the range of cell coverage. 
     Therefore an approach to more evenly distribute ACK/NACK bits from all the cells into the uplink reports may be desirable. This approach may define a superset configuration that is derived from all the cells by combining all of the uplink allocations in all of the cells. In two cases, the superset results in allocations that are not in the existing UL-DL configurations. All of the associations corresponding to these two new superset UL-DL configurations are new because these UL-DL configurations do not currently exist. 
     To more evenly distribute the ACK/NACK bits, the uplink association based on the superset UL-DL configurations may be used as the reference cell. The corresponding ACK/NACK bits are then transmitted on the selected uplink subframe. The association mapping approaches described previously may be used with the superset UL-DL configurations. For example, associations based on an association region may be used. In another example, associations based on balanced distribution may be used. 
     UL-DL configuration two+three (e.g., “2+3”) and UL-DL configuration two+four (e.g., “2+4”) may be new added configurations if UL-DL configurations with different periodicity may be used in inter-band carrier aggregation. The new superset UL-DL configurations may be used as reference UL-DL configurations. In one configuration, an association region mapping approach may be used for association mapping with the superset UL-DL configurations. In another configuration, a more even distribution mapping approach may be used for distribution mapping with superset UL-DL configurations. 
     If UL-DL configuration 2 and UL-DL configuration 3 are combined to form a superset UL-DL configuration, new uplink ACK/NACK report associations may need to be defined. In an association region based approach, the ACK/NACK for subframes 3, 4 and 5 of all of the cells may be reported in an uplink in subframe 2 of the next radio frame. Similarly, the ACK/NACK for subframes 6 and 7 of all of the cells may be reported in an uplink in subframe 3 of the next radio frame. Additionally, the ACK/NACK for subframes 8 and 9 of all of the cells may be reported in an uplink in subframe 4 of the next radio frame. Furthermore, the ACK/NACK for subframes 0 and 1 of all of the cells may be reported in an uplink in subframe 7 of the same radio frame. 
     If UL-DL configuration 2 and UL-DL configuration 4 are combined to form a superset UL-DL configuration, new uplink ACK/NACK report associations may need to be defined. In an association region based approach, the ACK/NACK for subframes 3, 4 and 5 of all of the cells may be reported in an uplink in subframe 2 of the next radio frame. Similarly, the ACK/NACK for subframes 6, 7 and 8 of all cells may be reported in an uplink in subframe 3 of the next radio frame. Additionally, the ACK/NACK for subframe 9 in the current radio frame and subframes 0 and 1 of the next radio frame of all cells may be reported in an uplink in subframe 7 of the next radio frame. 
     In another configuration, a more evenly distributed mapping approach may be used for association mapping with the superset UL-DL configurations. If UL-DL configurations with different periodicity may not be used in inter-band carrier aggregation, only existing UL-DL configurations (e.g., UL-DL configurations 0-6) may need to be used. To avoid using unspecified UL-DL allocations, the same periodicity setting may be used in all bands. In some configurations, the reference cell may need to be determined. In some cases, only one cell may be selected as the reference cell. The cell may be the PCell or one of a set of SCells. The ACK/NACK reporting may follow any of the approaches described previously (e.g., association region based mapping, more evenly distributed based mapping) based on the selected reference cell. Several rules for selecting the reference cell may be defined. 
     First, if cells have different periodicity (e.g., a combination of 5 ms and 10 ms periodicity), a cell with 5 ms periodicity may be selected as the reference cell. This is because 10 ms periodicity settings cannot satisfy the delay requirements of 5 ms periodicity. For example, if one cell in one band with UL-DL configuration 2 (that has 5 ms periodicity, for example), and another cell in another band with UL-DL configuration 4 (with 10 ms periodicity, for example), the cell with UL-DL configuration 2 should be used as the reference cell. The selected reference cell may be the PCell or an SCell. The ACK/NACK reporting may follow one of the association mapping approaches described previously. The association mapping approach selected may be based on the selected reference cell, and are reported on the selected reference cell. 
     Second, among cells with the same periodicity, the cell with more uplink allocation may be selected as the reference cell. An UL-DL configuration with more uplink allocation may provide more uplink reporting instances with lower ACK/NACK payloads than UL-DL configurations with less uplink allocation. For example, if one cell in one band with UL-DL configuration 2 (that has 5 ms periodicity with 2 UL allocations, for example), and another cell in another band with UL-DL configuration 1 (with 5 ms periodicity with 1 UL allocation, for example), the cell with the UL-DL configuration 2 (with the greater UL allocations, for example) may be used as the reference cell. The selected reference cell may be the PCell or an SCell. 
     The ACK/NACK reporting may follow one of the allocation mapping approaches described previously based on the selected reference cell. The associations may be obtained by using an association region mapping or may be obtained by using a more evenly distributed mapping. 
     In one implementation, the uplink report may be carried on the selected reference cell only. This approach simplifies the uplink channel monitoring. In another implementation, each uplink transmission (e.g., UL subframe) may perform the reference cell selection described above. For an uplink allocation in the reference cell, the actual uplink reporting may be carried on a cell with the uplink subframe that has the lowest Cell_ID. The cell with the lowest Cell_ID may or may not be the same as the reference cell. The PCell may always have the lowest Cell_ID (e.g., Cell_ID=0). In a subframe with an uplink subframe in the PCell, UCI is reported on the PUCCH or PUSCH of the PCell. In a subframe with a downlink subframe in the PCell and an uplink subframe in one or more of the SCells, the UCI may be reported on the PUCCH or PUSCH of one of the SCells. In case of multiple SCells that have an uplink subframe in the same subframe, the uplink subframe in the SCell with the lowest cell index (Cell_ID) may be used. 
     In some configurations, different association mapping approaches may be concurrently used on different cells. For example, a first association mapping approach may be used on the PCell while a second association mapping approach may be used on an SCell. 
     Various configurations are now described with reference to the Figures, where like reference numbers may indicate functionally similar elements. The systems and methods as generally described and illustrated in the Figures herein could be arranged and designed in a wide variety of different configurations. Thus, the following more detailed description of several configurations, as represented in the Figures, is not intended to limit scope, as claimed, but is merely representative of the systems and methods. 
       FIG. 1  is a block diagram illustrating one configuration of one or more evolved Node Bs (eNBs)  160  and one or more user equipments (UEs)  102  in which systems and methods for reporting uplink information with different duplexing configurations may be implemented. The one or more UEs  102  communicate with one or more evolved Node Bs  160  using one or more antennas  122   a - n . For example, a UE  102  transmits electromagnetic signals to the eNB  160  and receives electromagnetic signals from the eNB  160  using the one or more antennas  122   a - n . The eNB  160  communicates with the UE  102  using one or more antennas  180   a - n . It should be noted that the eNB  160  may be a Node B, home evolved Node B (HeNB) or other kind of base station in some configurations. 
     The UE  102  and the eNB  160  may use one or more channels  119 ,  121  to communicate with each other. For example, a UE  102  may transmit information or data to the eNB  160  using one or more uplink channels  121 . Examples of uplink channels  121  include a physical uplink control channel (PUCCH) and a physical uplink shared channel (PUSCH), etc. The one or more eNBs  160  may also transmit information or data to the one or more UEs  102  using one or more downlink channels  119 , for instance. Examples of downlink channels  119  include a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), etc. Other kinds of channels may be used. 
     Each of the one or more UEs  102  may include one or more transceivers  118 , one or more demodulators  114 , one or more decoders  108 , one or more encoders  150 , one or more modulators  154  and a UE operations module  124 . For example, one or more reception and/or transmission paths may be used in the UE  102 . For convenience, only a single transceiver  118 , decoder  108 , demodulator  114 , encoder  150  and modulator  154  are illustrated in the UE  102 , though multiple parallel elements (e.g., transceivers  118 , decoders  108 , demodulators  114 , encoders  150  and modulators  154 ) may be used depending on the implementation. 
     The transceiver  118  may include one or more receivers  120  and one or more transmitters  158 . The one or more receivers  120  may receive signals from the eNB  160  using one or more antennas  122   a - n . For example, the receiver  120  may receive and downconvert signals to produce one or more received signals  116 . The one or more received signals  116  may be provided to a demodulator  114 . The one or more transmitters  158  may transmit signals to the eNB  160  using one or more antennas  122   a - n . For example, the one or more transmitters  158  may upconvert and transmit one or more modulated signals  156 . 
     The demodulator  114  may demodulate the one or more received signals  116  to produce one or more demodulated signals  112 . The one or more demodulated signals  112  may be provided to the decoder  108 . The UE  102  may use the decoder  108  to decode signals. The decoder  108  may produce one or more decoded signals  106 ,  110 . For example, a first UE-decoded signal  106  may comprise received payload data  104 . A second UE-decoded signal  110  may comprise overhead data and/or control data. For example, the second UE-decoded signal  110  may provide data that may be used by the UE operations module  124  to perform one or more operations. 
     As used herein, the term “module” may mean that a particular element or component may be implemented in hardware, software or a combination of hardware and software. However, it should be noted that any element denoted as a “module” herein may alternatively be implemented in hardware. For example, the UE operations module  124  may be implemented in hardware, software or a combination of both. 
     In general, the UE operations module  124  may enable the UE  102  to communicate with the one or more eNBs  160 . The UE operations module  124  may include a UE configuration aggregation module  126 . The UE configuration aggregation module  126  may include UL-DL configurations  128 , cell mappings  130 , association mappings  132  and an aggregating module  134 . 
     The UL-DL configurations  128  may specify a set of UL-DL configurations that may be used for communication between the UE  102  and the eNB  160 . Examples of UL-DL configurations include the UL-DL configurations 0-6 described previously, superset configurations (e.g., configurations 2+3, 2+4), any other configuration, etc. The UL-DL configurations  128  may be used by the UE configuration aggregation module  126 , UE operations module  124  and the UE  102  for proper communication and scheduling. For example, the UL-DL configurations  128  may indicate the subframes for receiving information from the eNB  160  and may indicate the subframes for transmitting information to the eNB  160 . A UL-DL configuration may indicate a timing sequence for communication. For example, the UE  102  may receive during a DL subframe and may transmit during a UL subframe. For proper communication on a cell, the same UL-DL configuration  128  may be used by the UE  102  and the eNB  160  on the same cell. However, different UL-DL configurations  128  may be used on different cells. 
     The cell mappings  130  may indicate the number of cells that the UE  102  may be using to communicate with one or more eNBs  160 . The cell mappings  130  may additionally indicate the UL-DL configuration  128  (e.g., configuration 0-6, 2+3, 2+4, etc.) of each cell. For example, the UE  102  may communication with one or more eNBs  160  with a PCell and two SCells. The cell mappings  130  may indicate that the PCell includes a Cell_ID of 0 and that the PCell is using a particular UL-DL configuration  128  (e.g., configuration 2). The cell mappings  130  may also indicate that a first SCell includes a Cell_ID of 1 and that a first SCell is using a particular UL-DL configuration  128  (e.g., configuration 4). The cell mappings  130  may additionally indicate that a second SCell includes a Cell_ID of 2 and that the second SCell is using a particular UL-DL configuration  128  (e.g., configuration 5). 
     The association mappings  132  may indicate the uplink reporting associations for a particular UL-DL configuration  128  given a particular association mapping approach. For example, the UE configuration aggregation module  126  may indicate that the more evenly distributed mapping approach is to be used with the example cell mappings  130  described previously. For instance, ACK/NACK bits may be distributed as evenly as possible within a number of subframes. In this example, the association mappings  132  may specify more evenly distributed mappings for the PCell (e.g., mappings for configuration 2), the first SCell (e.g., mappings for configuration 4) and the second SCell (e.g., mappings for configuration 5). In one configuration, the association mappings  132  may include mapping tables. 
     The aggregating module  134  may aggregate the UCI (e.g., ACK/NACK bits) based on the association mappings  132  and the cell mappings  130 . The order of aggregation may be determined based on the Cell_ID (e.g., the cell mappings  130 ) of each cell. For example, the aggregating module  134  may first aggregate the ACK/NACK bits from Cell_ID 0 (e.g., PCell), then aggregate the ACK/NACK bits from Cell_ID 1 (e.g., a first SCell) and then aggregate the ACK/NACK bits from Cell_ID 2 (e.g., a second SCell). The aggregation module  134  may aggregate based on each UL subframe. Any uplink associations associated with a particular uplink subframe may be reported on that particular uplink subframe. The number of ACK/NACK bits that are reported on each UL subframe may depend on the association mappings  132  and the UL-DL configuration of each cell. The uplink associations for reporting ACK/NACK bits are described in greater detail below. 
     The UE operations module  124  may provide information  148  to the one or more receivers  120 . For example, the UE operations module  124  may inform the receiver(s)  120  when or when not to receive transmissions based on the UL-DL configurations  128  and cell mappings  130 . 
     The UE operations module  124  may provide information  138  to the demodulator  114 . For example, the UE operations module  124  may inform the demodulator  114  of a modulation pattern anticipated for transmissions from the eNB  160 . In some implementations, this may be based on the UL-DL configuration  128  of a given cell. 
     The UE operations module  124  may provide information  136  to the decoder  108 . For example, the UE operations module  124  may inform the decoder  108  of an anticipated encoding for transmissions from the eNB  160 . In some implementations, this may be based on the UL-DL configuration  128  of a give cell. 
     The UE operations module  124  may provide information  142  to the encoder  150 . The information  142  may include data to be encoded and/or instructions for encoding. For example, the UE operations module  124  may instruct the encoder  150  to encode transmission data  146  and/or control information  142  based on a UL-DL configuration  128  of a given cell. 
     The encoder  150  may encode transmission data  146  and/or other information  142  provided by the UE operations module  124 . For example, encoding the data  146  and/or other information  142  may involve error detection and/or correction coding, mapping data to space, time and/or frequency resources for transmission, multiplexing, etc. The encoder  150  may provide encoded data  152  to the modulator  154 . 
     The UE operations module  124  may provide information  144  to the modulator  154 . For example, the UE operations module  124  may inform the modulator  154  of a modulation type (e.g., constellation mapping) to be used for transmissions to the eNB  160 . In some configurations, this may be based on a UL-DL configuration  128 . The modulator  154  may modulate the encoded data  152  to provide one or more modulated signals  156  to the one or more transmitters  158 . 
     The UE operations module  124  may provide information  140  to the one or more transmitters  158 . This information  140  may include instructions for the one or more transmitters  158 . For example, the UE operations module  124  may instruct the one or more transmitters  158  when to transmit a signal to the eNB  160 . In some configurations, this may be based on a UL-DL configuration  128 . For instance, the one or more transmitters  158  may transmit during a downlink subframe. The one or more transmitters  158  may upconvert and transmit the modulated signal(s)  156  to one or more eNBs  160 . 
     The eNB  160  may include one or more transceivers  176 , one or more demodulators  172 , one or more decoders  166 , one or more encoders  109 , one or more modulators  113  and an eNB operations module  182 . For example, one or more reception and/or transmission paths may be used in an eNB  160 . For convenience, only a single transceiver  176 , decoder  166 , demodulator  172 , encoder  109  and modulator  113  are illustrated in the eNB  160 , though multiple parallel elements (e.g., transceivers  176 , decoders  166 , demodulators  172 , encoders  109  and modulators  113 ) may be used depending on the implementation. 
     The transceiver  176  may include one or more receivers  178  and one or more transmitters  117 . The one or more receivers  178  may receive signals from the UE  102  using one or more antennas  180   a - n . For example, the receiver  178  may receive and downconvert signals to produce one or more received signals  174 . The one or more received signals  174  may be provided to a demodulator  172 . The one or more transmitters  117  may transmit signals to the UE  102  using one or more antennas  180   a - n . For example, the one or more transmitters  117  may upconvert and transmit one or more modulated signals  115 . 
     The demodulator  172  may demodulate the one or more received signals  174  to produce one or more demodulated signals  170 . The one or more demodulated signals  170  may be provided to the decoder  166 . The eNB  160  may use the decoder  166  to decode signals. The decoder  166  may produce one or more decoded signals  164 ,  168 . For example, a first eNB-decoded signal  164  may comprise received payload data  162 . A second eNB-decoded signal  168  may comprise overhead data and/or control data. For example, the second UE-decoded signal  168  may provide data that may be used by the eNB operations module  182  to perform one or more operations. 
     The eNB operations module  182  may include an eNB configuration aggregation module  184 . The eNB configuration aggregation module  184  may include UL-DL configurations  194 , cell mappings  196 , association mappings  198  and a de-aggregating module  107 . 
     The UL-DL configurations  194  may specify the set of UL-DL configurations  194  that may be used for communication between the eNB  160  and a UE  102 . Examples of UL-DL configurations  194  include configurations 0-6 described previously, superset configurations (e.g., configurations 2+3, 2+4), any other configuration, etc. The UL-DL configurations  194  may be used by the eNB configuration aggregation module  184 , eNB operations module  182 , and the eNB  160  for proper communication and scheduling. For example, the UL-DL configurations  194  may indicate the subframes for receiving information from the UE  102  and may indicate the subframes for transmitting information to the UE  102 . A UL-DL configuration  196  may indicate a timing sequence for communication. For example, the UE  102  may receive during a DL subframe and may transmit during a UL subframe. Thus, for proper communication, the same UL-DL configuration  194  may be used by the eNB  160  and the UE  102  on the same cell. However, different UL-DL configurations  194  may be used on different cells. 
     The cell mappings  196  may indicate the number of cells that the eNB  160  may be using to communicate with a UE  102 . The cell mappings  196  may additionally indicate the UL-DL configuration  194  (e.g., configuration 0-6, 2+3, 2+4, etc.) of each cell. For example, an eNB  160  may be connected to a UE  102  with a PCell and two SCells. The cell mappings  196  may indicate that the eNB  160  is connected to the UE  102  using a PCell with a Cell_ID of 0 and that the PCell is using a particular UL-DL configuration  194  (e.g., configuration 2). The cell mappings  196  may also indicate that the eNB  160  is connected to the UE  102  using an SCell with a Cell_ID of 1 and that the SCell is using a particular UL-DL configuration  194  (e.g., configuration 4). The cell mappings  196  may additionally indicate that the eNB  160  is connected to the UE  102  using another SCell with a Cell_ID of 2 using a particular UL-DL configuration  194  (e.g., configuration 5). 
     The association mappings  198  may indicate the uplink reporting associations for a particular UL-DL configuration  194  given a particular association mapping approach. For example, the eNB configuration aggregation module  184  may indicate that the more evenly distributed mapping approach is to be used with the example cell mappings  196  described previously. In this example, the association mappings  198  may specify more evenly distributed mappings (as described above) for the PCell (e.g., mappings for configuration 2), the first SCell (e.g., mappings for configuration 4) and the second SCell (e.g., mappings for configuration 5). In one configuration, the association mappings  198  may include mapping tables. 
     The de-aggregating module  107  may de-aggregate the UCI (e.g., ACK/NACK bits) based on the association mappings  198  and the cell mappings  196 . The order of de-aggregation may be determined based on the Cell_ID (e.g., the cell mappings  196 ) of each cell. For example, the de-aggregating module  107  may de-aggregate the ACK/NACK bits from Cell_ID 0 (e.g., a PCell) from the ACK/NACK bits from Cell_ID 1 (e.g., a first SCell) and from the ACK/NACK bits from Cell_ID 2 (e.g., a second SCell). The de-aggregating module  107  may also de-aggregate the ACK/NACK bits from Cell_ID 1 (e.g., the first SCell) from the ACK/NACK bits from Cell_ID 2 (e.g., the second SCell). The de-aggregation module  107  may de-aggregate based on each UL subframe. The number of ACK/NACK bits that are reported on each UL subframe may depend on the association mappings  198  and the UL-DL configuration  194  of each cell. The uplink associations for reporting ACK/NACK bits are described in further detail below. 
     The eNB operations module  182  may provide information  190  to the one or more receivers  178 . For example, the eNB operations module  182  may inform the receiver(s)  178  when or when not to receive transmissions based on a UL-DL configuration  194  for a given cell. 
     The eNB operations module  182  may provide information  188  to the demodulator  172 . For example, the eNB operations module  182  may inform the demodulator  172  of a modulation pattern anticipated for transmissions from the UE(s)  102 . In some configurations, this may be based on an UL-DL configuration  194  for a given cell. 
     The eNB operations module  182  may provide information  186  to the decoder  166 . For example, the eNB operations module  182  may inform the decoder  166  of an anticipated encoding for transmissions from the UE(s)  102 . In some configurations, this may be based on a UL-DL configuration  194  for a given cell. 
     The eNB operations module  182  may provide information  101  to the encoder  109 . The information  101  may include data to be encoded and/or instructions for encoding. For example, the eNB operations module  182  may instruct the encoder  109  to encode transmission data  105  and/or control information  101  based on a UL-DL configuration  194  for a given cell. 
     The encoder  109  may encode transmission data  105  and/or other information  101  provided by the eNB operations module  182 . For example, encoding the data  105  and/or other information  101  may involve error detection and/or correction coding, mapping data to space, time and/or frequency resources for transmission, multiplexing, etc. The encoder  109  may provide encoded data  111  to the modulator  113 . The transmission data  105  may include network data to be relayed to the UE  102 . 
     The eNB operations module  182  may provide information  103  to the modulator  113 . This information  103  may include instructions for the modulator  113 . For example, the eNB operations module  182  may inform the modulator  113  of a modulation type (e.g., constellation mapping) to be used for transmissions to the UE(s)  102 . In some configurations, this may be based on a UL-DL configuration  194  for a given cell. The modulator  113  may modulate the encoded data  111  to provide one or more modulated signals  115  to the one or more transmitters  117 . 
     The eNB operations module  182  may provide information  192  to the one or more transmitters  117 . This information  192  may include instructions for the one or more transmitters  117 . For example, the eNB operations module  182  may instruct the one or more transmitters  117  when to (or when not to) transmit a signal to the UE(s)  102 . In some implementations, this may be based on a current configuration  148 . The one or more transmitters  117  may upconvert and transmit the modulated signal(s)  115  to one or more UEs  102 . 
     It should be noted that a downlink subframe may be transmitted from the eNB  160  to one or more UEs  102  and that an uplink subframe may be transmitted from one or more UEs  102  to the eNB  160 . Furthermore, both the eNB  160  and the one or more UEs  102  may transmit data in a standard special subframe. 
       FIG. 2  is a flow diagram illustrating one configuration of a method  200  for reporting information on a UE  102 . A UE  102  may select  202  a reference cell having a reference UL-DL configuration. The UE  102  may select the reference cell based on cell mappings  130 . In one configuration, the reference cell may be the cell with the lowest Cell_ID. For example, the PCell may be selected as the reference cell. In another configuration, the reference cell may be determined for each uplink subframe for any of the cells. In this configuration, the cell with the lowest Cell_ID for a particular uplink subframe may be selected as the reference cell. 
     The reference cell may have a reference UL-DL configuration. The cell mappings  130  may specify the UL-DL configuration for a particular cell. In one configuration, the reference UL-DL configuration may be the UL-DL configuration of the reference cell. In another configuration, the reference UL-DL configuration may be a UL-DL configuration that is different from the UL-DL configurations specified in the cell mappings  130 . The reference UL-DL configuration may be one of the UL-DL configurations specified in UL-DL configurations  128 . 
     The UE  102  may select  204  a first uplink subframe from the reference cell. For example, the UE  102  may select  204  a first uplink subframe for uplink reporting. Each UL-DL configuration in the UL-DL configurations  128  may have different configurations of uplink subframes. Selecting  204  a first uplink subframe may include selecting  204  the first uplink subframe with an existing uplink association. The existing uplink associations may be specified in the association mappings  132 . In some configurations, multiple uplink subframes (e.g., at least one additional uplink subframe) may be selected. 
     The UE  102  may select  206  a first subframe set from a first cell having a first UL-DL configuration. The first cell may be a different cell than the reference cell. For example, the first cell may be in a first band and the reference cell may be in a second band. The first UL-DL configuration may be the same as or different from the reference UL-DL configuration. For example, the first UL-DL configuration may be a configuration 1 UL-DL configuration and the reference UL-DL configuration may be a configuration 1 UL-DL configuration. In another example, the first UL-DL configuration may be a configuration 1 UL-DL configuration and the reference UL-DL configuration may be a configuration 0 UL-DL configuration. The reference cell with the reference UL-DL configuration and the first cell with the first UL-DL configuration may be specified in the cell mappings  130 . In some configurations, multiple subframe sets (e.g., at least one additional subframe set) may be selected from a first cell. 
     The subframe set may refer to one or more subframes of one or more types (e.g., downlink subframe, special subframe, uplink subframe, etc.). For example, the subframe set may include subframes that are downlink subframes and/or special subframes in the first cell that correspond with uplink subframes in the reference cell (there may not be an existing uplink association (according to current 3GPP specifications) in the reference cell for each of the subframes in the subframe set in the first cell, for example). 
     The UE  102  may determine  208  a first set of associations between the first subframe set and the first uplink subframe. An association may be an uplink association that enables a first cell with a first UL-DL configuration to do ACK/NACK reporting on the on the selected reference cell even though the reference cell may be using a different UL-DL configuration. The first set of associations may include an uplink association for each subframe in the subframe set. The first set of associations may be specified (e.g., stored) in the association mappings  132 . It should be noted that a set of associations may include one or more associations. 
     The first set of associations may be determined  208  according to one or more association approaches. In one example, the uplink associations may be determined  208  to minimize the number of subframes between the associated subframe and the uplink subframe (e.g., the distance of an association). In other words, the distance between subframes may be the difference between subframe numbering associated with the subframes. In another example, the uplink associations may be determined  208  to minimize the total distance of all of the associations. In yet another example, an association may be determined  208  based on a minimum association distance of 4 subframes (e.g., 4 milliseconds). 
     In some configurations, multiple sets of associations (e.g., at least one additional set of associations) may be determined  208 . An additional set of associations may be between an additional subframe set (e.g., from a first cell) and an additional uplink subframe (e.g., from a reference cell). 
     In some configurations, multiple cells may utilize the systems and methods described herein. For example, a combination of cells may be used. In one case, all of the cells may have the same UL-DL configuration. For example, the PCell may have a UL-DL configuration of 6 and all of the SCells may each have the same UL-DL configuration (e.g., configuration 2). In another case, some of the cells may have different UL-DL configurations. For example, the PCell may have a UL-DL configuration of 6 and all of the SCells may each have different UL-DL configuration (e.g., configurations 0-6). In another example, the PCell may have a UL-DL configuration of 6 and some of the SCells may have a variety of UL-DL configurations (e.g., some configuration 2, some configuration 1, some configuration 6, etc.). 
     The UE  102  may aggregate  210  information corresponding to the reference cell and information corresponding to the first cell based on the first set of associations to produce aggregated information. For example, the aggregating module  134  may aggregate the uplink reporting information from the subframes in the reference cell that are associated to the first uplink subframe. Examples of uplink reporting information include ACK/NACK, channel state information (CSI), uplink control information (UCI), etc. The aggregating module  134  may also aggregate the uplink reporting information from the subframes in the first cell that are associated to the first uplink subframe. The aggregating module  134  may additionally aggregate the uplink reporting information from any subframes from any additional cells that are associated with the first uplink subframe. For example, the aggregating module  134  may order the aggregation of information based on the Cell_ID of the cells. For instance, the information associated with the reference cell may be aggregated first because the reference cell may have the lowest Cell_ID. The information associated with the next lowest Cell_ID may be aggregated together and so forth. The aggregating module  134  may aggregate the information to produce aggregated information. 
     In one configuration, aggregated information (e.g., ACK/NACK bits) may be multiplexed together based on a lowest Cell_ID ordering. In this case, the uplink reporting information of the first cell may be multiplexed with (e.g., added to) the uplink reporting information of the reference cell. Thus, the aggregated information is aggregated with the standard uplink reporting of the reference cell. 
     The UE  102  may report  212  the aggregated information on an uplink reporting cell. For example, the UE  102  may report  212  aggregated ACK/NACK in one or more uplink subframes based on one or more associations corresponding to a subframe region mapping. In another example, the UE  102  may report  212  aggregated ACK/NACK based on the PCell uplink configuration. In another example, the UE  102  may report  212  aggregated ACK/NACK based on the cell with the maximum uplink allocation (e.g., the cell with the most uplink subframes). In yet another example, the UE  102  may report  212  aggregated ACK/NACK based on a cell with the aggregated uplink allocation of all cells (e.g., based on a superset configuration as described in connection with  FIG. 21  below). It should be noted that the UE  102  may additionally multiplex and/or bundle ACK/NACK bits in order to report  212  the aggregated information as described herein. 
     The aggregated information may be reported  212  in the place of the standard uplink reporting on the uplink reporting cell. In one configuration, the uplink reporting cell is the PCell only. In this configuration, the uplink reporting may be consistent with current specification uplink reporting (e.g., 3GPP Releases 8, 9 and 10). This may be beneficial because it is backwards compatible. For example, the same uplink reporting routines may be used regardless of the number of cells that are aggregated. Furthermore, cells with different UL-DL configurations may be added, removed or reconfigured without changing the uplink reporting on the PCell. In another configuration, the uplink reporting cell may be a serving cell (e.g., PCell, SCell or a combination of the PCell and one or more SCells). In another configuration, the uplink reporting cell may be the reference cell. 
       FIG. 3  is a flow diagram illustrating one configuration of a method  300  for receiving information on an eNB  160 . An eNB  160  may determine  302  if aggregated information is being used in connection with a first cell having a first UL-DL configuration and a second cell having a second UL-DL configuration. For example, the eNB  160  may determine  302  this based on the cell mappings  196  (e.g., that the eNB  160  assigned to the UE  102 ) that the eNB  160  may be communicating to the same device (e.g., a UE  102 ) on a first cell having a first UL-DL configuration and a second cell having a second UL-DL configuration. The eNB  160  may additionally determine  302  that a certain association mapping has been specified for use (the eNB  160  directed a UE  102  to use a specific association mapping approach, for example). 
     In some configurations, the eNB  160  may determine  302  if aggregated information is being used by comparing the size of the uplink reporting payload with characteristic uplink reporting payloads (e.g., non-aggregation payloads, association region based payloads, more evenly distributed based payloads, etc.). In other configurations, the eNB  160  may receive an indication that aggregate information is being used. 
     The eNB  160  may receive  304  the aggregated information. The aggregated information may be received in the same manner that non-aggregated information may be received. More particularly, the eNB  160  may receive  304  the aggregated information in place of the uplink reporting information for the reference cell. In some configurations, an eNB  160  may receive  304  aggregated information that includes uplink reporting information for one or more cells that are hosted by one or more eNBs  160 . 
     The eNB  160  may de-aggregate  306  the aggregated information based on a set of associations. For example, the de-aggregating module  107  may separate the aggregated information based on the association mappings  198  and the cell mappings  196 . More specifically, the de-aggregating module  107  may determine the Cell_ID for each of the cells that may be utilizing the aggregated uplink reporting. The de-aggregating module  107  may additionally determine the UL-DL configuration for each of the cells (based on the cell mappings  196  and the UL-DL configurations  194 ). The de-aggregating module  107  may also determine the association mapping approach being used for each cell. Thus, the de-aggregating module  107  may determine the specific uplink reporting bits associated with the particular subframes of the particular cells. The de-aggregating module  107  may parse through the aggregated information to de-aggregate the uplink reporting information for each particular cell. In some cases, the uplink reporting information for a cell associated with another eNB  160  may be transmitted to the other eNB  160 . 
       FIG. 4  is a diagram illustrating one example of a radio frame  435  that may be used in accordance with the systems and methods disclosed herein. This radio frame  435  structure may be applicable in time-division duplexing (TDD) approaches. Each radio frame  435  may have a length of T f =307200·T s =10 milliseconds (ms), where T f  is a radio frame  435  duration and T s  is a time unit equal to 
             1     (     15000   ×   2048     )           
seconds. The radio frame  435  may include two half-frames  437 , each having a length of 153600·T s =5 ms. Each half-frame  437  may include five subframes  423   a - e ,  423   f - j  each having a length of 30720·T s =1 ms.
 
     In accordance with the systems and methods disclosed herein, some types of subframes  423  that may be used include a downlink subframe, an uplink subframe and a special subframe  431 . In the example illustrated in  FIG. 4 , two standard special subframes  431   a - b  are included in the radio frame  435 . 
     The first standard special subframe  431   a  includes a downlink pilot time slot (DwPTS)  425   a , a guard period (GP)  427   a  and an uplink pilot time slot (UpPTS)  429   a . In this example, the first standard special subframe  431   a  is included in subframe one  423   b . The second standard special subframe  431   b  includes a downlink pilot time slot (DwPTS)  425   b , a guard period (GP)  427   b  and an uplink pilot time slot (UpPTS)  429   b . In this example, the second standard special subframe  431   b  is included in subframe six  423   g . The length of the DwPTS  425   a - b  and UpPTS  429   a - b  may be given by Table 4.2-1 of 3GPP TS 36.211 (illustrated in Table 9 above) subject to the total length of each set of DwPTS  425 , GP  427  and UpPTS  429  being equal to 30720·T s =1 ms. 
     Each subframe i  423   a - j  (where i denotes a subframe ranging from subframe zero  423   a  (e.g., 0) to subframe nine  423   j  (e.g., 9) in this example) is defined as two slots, 2i and 2i+1 of length T slot =15360·T s =0.5 ms in each subframe  423 . For example, subframe zero (e.g., 0)  423   a  may include two slots, including a first slot. 
     UL-DL configurations with both 5 ms and 10 ms downlink-to-uplink switch-point periodicity may be used in accordance with the systems and methods disclosed herein.  FIG. 4  illustrates one example of a radio frame  435  with 5 ms switch-point periodicity. In the case of 5 ms downlink-to-uplink switch-point periodicity, each half-frame  437  includes a standard special subframe  431   a - b . In the case of 10 ms downlink-to-uplink switch-point periodicity, a special subframe may exist in the first half-frame  437  only. 
     Subframe zero (e.g., 0)  423   a  and subframe five (e.g., 5)  423   f  and DwPTS  425   a - b  may be reserved for downlink transmission. The UpPTS  429   a - b  and the subframe(s) immediately following the special subframe(s)  431   a - b  (e.g., subframe two  423   c  and subframe seven  423   h ) may be reserved for uplink transmission. 
       FIGS. 5-27  illustrate various examples of association mappings for interband carrier aggregation with different UL-DL configurations. The association regions and the subframes that map to the distribution regions may be examples of sets of subframes or subframe sets as described in connection with  FIG. 2  above. For instance, the first association region described in  FIG. 5  may be one example of a first subframe set as described in  FIG. 2 . Similarly, the subframes that map to the first distribution region described in  FIG. 14  may be another example of a first subframe set as described in  FIG. 2 . The UL-DL configurations referred to in  FIGS. 5-27  may correspond to configurations 0-6 described previously. It should be noted that in  FIGS. 5-27 , “D” denotes a downlink subframe, “U” denotes an uplink subframe and “S” denotes a special subframe. 
       FIGS. 5-13  illustrate various examples of association regions in accordance with the systems and methods disclosed herein. In general, an association region is a region that includes one or more subframes (e.g., a subframe set or set of subframes) that map to one or more particular uplink subframes. Downlink subframes and special subframes may report an acknowledgment (ACK) if data was properly received or a negative acknowledgment (NACK) if data was improperly received or not received at all. This ACK/NACK reporting for a subframe (e.g., downlink subframe, special subframe) may be reported during an uplink subframe. An association exists between a subframe and an uplink subframe where the uplink reporting (e.g., ACK/NACK, CSI, UCI, etc.) for that subframe occurs. A set of associations exists for each of the seven defined UL-DL configurations. These existing associations are specified in Table 10. In Table 10, a number specified for a particular subframe is an uplink reporting subframe for the numbers listed. The numbers listed refer to a subframe previous to the reporting subframe. For example, in Table 10, under configuration 1 and subframe 2 are the numbers 7 and 6. This means that in configuration 1, subframe 2 does uplink reporting for the subframes that are 7 subframes and 6 subframes previous to subframe 2. In other words, subframe 2 provides uplink reporting for subframe 5 and subframe 6 of the previous radio frame, which may be a downlink subframe and a special subframe. 
     When only a single UL-DL configuration is used (e.g., all the cells use the same UL-DL configurations), the standard associations listed in Table 10 may provide all of the necessary uplink reporting. However, when multiple UL-DL configurations are used (e.g., cells using different UL-DL configurations) the standard associations may not provide all of the necessary uplink reporting. Different UL-DL configurations may have different subframes that need uplink reporting. In one implementation, an association region may be defined for a reference configuration that identifies a region of subframes (e.g., association region) that maps to a particular uplink subframe for uplink reporting. The association region may add new uplink reporting associations that allow for uplink reporting for any UL-DL configuration. Table 11 identifies the existing associations and the added associations (in parentheses) for the association regions for each UL-DL configuration. 
     Association regions may be described in further detail with reference to the Figures below. For convenience, association regions are indicated in a dotted outline. The association regions illustrated may specify examples of sets of associations as described above (in connection with  FIG. 2 , for example). 
       FIG. 5  is a diagram illustrating several examples of association regions for uplink reporting in accordance with the systems and methods disclosed herein. For convenience, existing associations  543  (in current 3GPP specifications) may be indicated with solid lines and possible associations  545  that have been added based on the association region mappings may be indicated with dashed lines. Each of the subframes  523  may correspond to a subframe number  539 . The subframes  523  may be referred to according to subframe numbers  539 . 
     Configuration zero  541   a  (e.g., “0”) corresponds to six association regions  547   a . A first association region  547   a  for configuration zero  541   a  includes subframes 6 and 7 and includes association mappings to the uplink subframe 2 in the next radio frame. The association from subframe 6 to the uplink subframe 2 is an existing association mapping  543  of configuration zero  541   a . The association mapping from subframe 7 to the uplink subframe 2 is a new association mapping  545  for configuration zero  541   a.    
     A second association region  547   a  for configuration zero  541   a  includes subframes 8 and 9 and includes association mappings to the uplink subframe 3 in the next radio frame. The association from subframe 8 to the uplink subframe 3 and the association from subframe 9 to the uplink subframe 3 are new association mappings  545  for configuration zero  541   a.    
     A third association region  547   a  for configuration zero  541   a  includes subframe 0 and includes an association mapping to the uplink subframe 4 in the current radio frame. The association from subframe 0 to the uplink subframe 4 is an existing association mapping  543  of configuration zero  541   a.    
     A fourth association region  547   a  for configuration zero  541   a  includes subframe 1 and includes an association mapping to the uplink subframe 7 in the current radio frame. The association from subframe 1 to the uplink subframe 7 is an existing association mapping  543  of configuration zero  541   a.    
     A fifth association region  547   a  for configuration zero  541   a  includes subframes 3 and 4 and includes association mappings to the uplink subframe 8 in the current radio frame. The association from subframe 3 to the uplink subframe 8 and the association from subframe 4 to the uplink subframe 8 are new association mappings  545  for configuration zero  541   a.    
     A sixth association region  547   a  for configuration zero  541   a  includes subframe 5 and includes an association mapping to the uplink subframe 9 in the current radio frame. The association from subframe 5 to the uplink subframe 9 is an existing association mapping  543  of configuration zero  541   a.    
     Configuration one  541   b  (e.g., “1”) corresponds to four association regions  547   b . A first association region  547   b  for configuration one  541   b  includes subframes 5 and 6 and includes association mappings to the uplink subframe 2 in the next radio frame. The association mappings from subframes 5 and 6 to the uplink subframe 2 are existing association mappings  543  of configuration one  541   b.    
     A second association region  547   b  for configuration one  541   b  includes subframes 7, 8 and 9 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mappings from subframes 7 and 8 to the uplink subframe 3 are new association mappings  545  for configuration one  541   b . The association from subframe 9 to the uplink subframe 3 is an existing association mapping  543  for configuration one  541   b.    
     A third association region  547   b  for configuration one  541   b  includes subframes 0 and 1 and includes association mappings to the uplink subframe 7 in the same radio frame. The association mappings from subframe 0 and 1 to the uplink subframe 7 are existing association mappings  543  for configuration one  541   b.    
     A fourth association region  547   b  for configuration one  541   b  includes subframes 3 and 4 and includes association mappings to the uplink subframe 8 in the same radio frame. The association mapping from subframe 3 to the uplink subframe 8 is a new association mapping  545  for configuration one  541   b . The association from subframe 4 to the uplink subframe 8 is an existing association mapping  543  for configuration one  541   b.    
     Configuration two  541   c  (e.g., “2”) corresponds to two association regions  547   c . A first association region  547   c  for configuration two  541   c  includes subframes 4, 5, 6, 7 and 8 and includes association mappings to the uplink subframe 2 in the next radio frame. The association mappings from subframes 4, 5, 6 and 8 to the uplink subframe 2 are existing association mappings  534  for configuration two  541   c . The association mapping from subframe 7 to the uplink subframe 2 is a new association mapping  545  for configuration two  541   c.    
     A second association region  547   c  for configuration two  541   c  includes subframes 9, 0, 1 and 3 and includes association mappings to the uplink subframe 7. The association mappings from subframes 9, 0, 1 and 3 to the uplink subframe 7 are existing association mappings  543  for configuration two  541   c.    
     Configuration three  541   d  (e.g., “3”) corresponds to three association regions  547   d . A first association region  547   d  for configuration three  541   d  includes subframes 1, 3, 4, 5 and 6 and includes association mappings to the uplink subframe 2 in the next radio frame. The association mappings from subframe 1, 5 and 6 to the uplink subframe 2 are existing association mappings  543  for configuration three  541   d . The association mappings from subframe 3 and 4 are new association mappings  545  for configuration three  541   d.    
     A second association region  547   d  for configuration three  541   d  includes subframes 7 and 8 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mappings from subframe 7 and 8 to the uplink subframe 3 are existing association mappings  543  for configuration three  541   d.    
     A third association region  547   d  for configuration three  541   d  includes subframes 9 and 0 and includes association mappings to the uplink subframe 4. The association mappings from subframe 9 and 0 to the uplink subframe 4 are existing association mappings  543  for configuration three  541   d.    
       FIG. 6  is a diagram illustrating several examples of association regions for uplink reporting in accordance with the systems and methods disclosed herein. For convenience, existing associations  643  (in current 3GPP specifications) may be indicated with solid lines and possible associations  645  that have been added based on the association region mappings may be indicated with dashed lines. Each of the subframes  623  may correspond with a subframe number  639 . The subframes  623  may be referred to according to subframe numbers  639 . 
     Configuration four  641   e  (e.g., “4”) corresponds to two association regions  647   e . A first association region  647   e  for configuration four  641   e  includes subframes 0, 1, 3, 4 and 5 and includes association mappings to the uplink subframe 2 in the next radio frame. The association mappings from subframes 0, 1, 4 and 5 to the uplink subframe 2 are existing association mappings  634  for configuration four  641   e . The association mapping from subframe 3 to the uplink subframe 2 is a new association mapping  645  for configuration four  641   e.    
     A second association region  647   e  for configuration four  641   e  includes subframes 6, 7, 8 and 9 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mappings from subframes 6, 7, 8 and 9 to the uplink subframe 3 are existing association mappings  643  for configuration four  641   e.    
     Configuration five  641   f  (e.g., “5”) corresponds to one association region  647   e . A first association region  647   f  for configuration five  641   f  includes subframes 9, 0, 1, 3, 4, 5, 6, 7 and 8 and includes association mappings to the uplink subframe 2 in the next radio frame. The association mappings from subframes 9, 0, 1, 3, 4, 5, 6, 7 and 8 to the uplink subframe 2 are existing association mappings  643  for configuration five  641   f.    
     Configuration six  641   g  (e.g., “6”) corresponds to five association regions  647   g . A first association region  647   g  for configuration six  641   g  includes subframe 5 and includes an association mapping to the uplink subframe 2 in the next radio frame. The association mapping from subframe 5 to the uplink subframe 2 is an existing association mapping  643  for configuration six  641   g.    
     A second association region  647   g  for configuration six  641   g  includes subframes 6 and 7 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mapping from subframe 6 to the uplink subframe 2 is an existing association mapping  643  for configuration six  641   g . The association mapping from subframe 7 to the uplink subframe 2 is a new association mapping  645  for configuration six  641   g.    
     A third association region  647   g  for configuration six  641   g  includes subframes 8 and 9 and includes association mappings to the uplink subframe 4 in the next radio frame. The association mapping from subframe 8 to the uplink subframe 4 is a new association mapping  645  for configuration six  641   g . The association mapping from subframe 9 to the uplink subframe 4 is an existing association mapping  643  for configuration six  641   g.    
     A fourth association region  647   g  for configuration six  641   g  includes subframe 0 and includes an association mapping to the uplink subframe 7 in the same radio frame. The association mapping from subframe 0 to the uplink subframe 7 is an existing association mapping  643  for configuration six  641   g.    
     A fifth association region  647   g  for configuration six  641   g  includes subframes 1, 3 and 4 and includes an association mapping to the uplink subframe 8 in the same radio frame. The association mapping from subframe 1 to the uplink subframe 8 is an existing association mapping  643  for configuration six  641   g . The association mappings from subframes 3 and 4 to the uplink subframe 8 are new association mappings  645  for configuration six  641   g.    
       FIG. 7  illustrates more specifically the association regions for configuration zero  741   a  with respect to other UL-DL configurations  741   b - g . For example, the association regions  747   a  illustrated in  FIG. 7  may be the same as the association regions  547   a  illustrated in  FIG. 5  as applied to other UL-DL configurations  741   b - g . The configurations  741   a - g  in  FIG. 7  are illustrated as subframes  723   a - g  with corresponding subframe numbers  739   a - g . Table 12 below indicates the existing associations  743  for configuration zero  741   a  and the added associations  745  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE (12) 
               
             
            
               
                   
               
               
                 UL-DL 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Configuration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 0 (Ref. Cell) 
                 — 
                 — 
                 6 
                 — 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                 1 
                 — 
                 — 
                 6 
                 4 
                 4 
                 — 
                 — 
                 6 
                 4 
                 4 
               
               
                 2 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
               
               
                 3 
                 — 
                 — 
                 6, 5 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                 4 
                 — 
                 — 
                 6, 5 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 4 
                 4 
               
               
                 5 
                 — 
                 — 
                 6, 5 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
               
               
                 6 
                 — 
                 — 
                 6 
                 4 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 12 allow for uplink reporting from the association regions for configuration zero  741   a  described previously with respect to  FIG. 5 . For example, the first association region  747   a  for configuration zero  741   a  captures the additional downlink subframes (e.g., subframe 7) for configuration three  741   d , configuration four  741   e  and configuration five  741   f . As illustrated, the association regions  747   a  for configuration zero  741   a  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 8  illustrates more specifically the association regions for configuration one  841   b  with respect to other UL-DL configurations  841   a ,  841   c - g . For example, the association regions  847   b  illustrated in  FIG. 8  may be the same as the association regions  547   b  illustrated in  FIG. 5  as applied to other UL-DL configurations  841   a,c - g . The configurations  841   a - g  in  FIG. 8  are illustrated as subframes  823   a - g  with corresponding subframe numbers  839   a - g . Table 13 below indicates the existing associations  843  for configuration one  841   b  and the added associations  845  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE (13) 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 1 (Ref. Cell) 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
               
               
                 0 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 7, 6 
                 4, 5 
                 — 
                 — 
                 — 
                 7, 6 
                 4, 5 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6 
                 4, 6, 5 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 7, 6 
                 4, 6, 5 
                 — 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
               
               
                 5 
                 — 
                 — 
                 7, 6 
                 4, 6, 5 
                 — 
                 — 
                 — 
                 7, 6 
                 4, 5 
                 — 
               
               
                 6 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 13 allow for uplink reporting from the association regions for configuration one  841   b  described previously with respect to  FIG. 5 . For example, the second association region  847   b  for configuration one  841   b  captures the additional downlink subframes (e.g., subframes 7 and 8) for configuration two  841   c , configuration three  841   d , configuration four  841   e  and configuration five  841   f . As illustrated, the association regions  847   b  for configuration one  841   b  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 9  illustrates more specifically the association regions for configuration two  941   c  with respect to other UL-DL configurations  941   a - b ,  941   d - g . For example, the association regions  947   c  illustrated in  FIG. 9  may be the same as the association regions  547   c  illustrated in  FIG. 5  as applied to other UL-DL configurations  941   a - b,d - g . The configurations  941   a - g  in  FIG. 9  are illustrated as subframes  923   a - g  with corresponding subframe numbers  939   a - g . Table 14 below indicates the existing associations  943  for configuration two  941   c  and the added associations  945  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE (14) 
               
             
            
               
                   
               
               
                 UL-DL 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 Configuration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 (Ref. Cell) 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
               
               
                 0 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 4, 6, 5 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7, 4, 6, 5 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 8, 7, 4, 6, 5 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
               
               
                 6 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 14 allow for uplink reporting from the association regions for configuration two  941   c  described previously with respect to  FIG. 5 . For example, the first association region  947   c  for configuration two  941   c  captures the additional downlink subframes (e.g., subframe 7) for configuration three  941   d , configuration four  941   e  and configuration five  941   f . As illustrated, the association regions  947   c  for configuration two  941   c  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 10  illustrates more specifically the association regions for configuration three  1041   d  with respect to other UL-DL configurations  1041   a - c ,  1041   e - g . For example, the association regions  1047   d  illustrated in  FIG. 10  may be the same as the association regions  547   d  illustrated in  FIG. 5  as applied to other UL-DL configurations  1041   a - c,e - g . The configurations  1041   a - g  in  FIG. 10  are illustrated as subframes  1023   a - g  with corresponding subframe numbers  1039   a - g . Table 15 below indicates the existing associations  1043  for configuration three  1041   d  and the added associations  1045  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 15 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 3 (Ref. 
                 — 
                 — 
                 7, 6, 11 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
               
               
                 0 
                 — 
                 — 
                 7, 6, 11 
                 — 
                 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 7, 6, 11, 8 
                 — 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 7, 6, 11, 9, 8 
                 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 7, 6, 11, 8 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 7, 6, 11, 9, 8 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 6 
                 — 
                 — 
                 7, 6, 11 
                 — 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 15 allow for uplink reporting from the association regions for configuration three  1041   d  described previously with respect to  FIG. 5 . For example, the first association region  1047   d  for configuration three  1041   d  captures the additional downlink subframes (e.g., subframe 3 and 4) for configuration one  1041   b , configuration two  1041   c , configuration four  1041   e  and configuration five  1041   f . As illustrated, the association regions  1047   d  for configuration three  1041   d  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 11  illustrates more specifically the association regions for configuration four  1141   e  with respect to other UL-DL configurations  1141   a - d ,  1141   f - g . For example, the association regions  1147   e  illustrated in  FIG. 11  may be the same as the association regions  647   e  illustrated in  FIG. 6  as applied to other UL-DL configurations  1141   a - d,f - g . The configurations  1141   a - g  in  FIG. 11  are illustrated as subframes  1123   a - g  with corresponding subframe numbers  1139   a - g . Table 16 below indicates the existing associations  1143  for configuration four  1141   e  and the added associations  1145  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 16 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 4 (Ref. 
                 — 
                 — 
                 12, 8, 7, 11 
                 6, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
                   
                   
                   
                 7 
               
               
                 0 
                 — 
                 — 
                 12, 7, 11 
                 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 12, 8, 7, 11 
                 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 12, 8, 7, 11, 
                 5, 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 9 
               
               
                 3 
                 — 
                 — 
                 12, 7, 11 
                 6, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                   
                 7 
               
               
                 5 
                 — 
                 — 
                 12, 8, 7, 11, 
                 6, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 9 
                 7 
               
               
                 6 
                 — 
                 — 
                 12, 7, 11 
                 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 16 allow for uplink reporting from the association regions for configuration four  1141   e  described previously with respect to  FIG. 6 . For example, the first association region  1147   e  for configuration four  1141   e  captures the additional downlink subframe (e.g., subframe 3) for configuration two  1141   c  and configuration five  1141   f . As illustrated, the association regions  1147   e  for configuration four  1141   e  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 12  illustrates more specifically the association regions for configuration five  1241   f  with respect to other UL-DL configurations  1241   a - e ,  1241   g . For example, the association regions  1247   f  illustrated in  FIG. 12  may be the same as the association regions  647   f  illustrated in  FIG. 6  as applied to other UL-DL configurations  1241   a - e,g . The configurations  1241   a - g  in  FIG. 12  are illustrated as subframes  1223   a - g  with corresponding subframe numbers  1239   a - g . Table 17 below indicates the existing associations  1243  for configuration four  1241   f  and the added associations  1245  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 17 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 5 (Ref. 
                 — 
                 — 
                 13, 12, 9, 8, 7, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
                   
                   
                 5, 4, 11, 6 
               
               
                 0 
                 — 
                 — 
                 12, 7, 11, 6 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 13, 12, 8, 7, 11, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 6 
               
               
                 2 
                 — 
                 — 
                 13, 12, 9, 8, 7, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 4, 11, 6 
               
               
                 3 
                 — 
                 — 
                 13, 12, 7, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 11, 6 
               
               
                 4 
                 — 
                 — 
                 13, 12, 8, 7, 5, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 4, 11, 6 
               
               
                 6 
                 — 
                 — 
                 13, 12, 7, 11, 6 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 17 allow for uplink reporting from the association regions for configuration five  1241   f  described previously with respect to  FIG. 6 . As illustrated, the association regions  1247   f  for configuration five  1241   f  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 13  illustrates more specifically the association regions for configuration six  1341   g  with respect to other UL-DL configurations  1341   a - f . For example, the association regions  1347   g  illustrated in  FIG. 13  may be the same as the association regions  647   g  illustrated in  FIG. 6  as applied to other UL-DL configurations  1341   a - f . The configurations  1341   a - g  in  FIG. 13  are illustrated as subframes  1323   a - g  with corresponding subframe numbers  1339   a - g . Table 18 below indicates the existing associations  1343  for configuration six  1341   g  and the added associations  1345  for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 18 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 6 (Ref. 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 Cell) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 1 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7 
                 7, 4 
                 — 
               
               
                 2 
                 — 
                 — 
                 7 
                 7 
                 5, 6 
                 — 
                 — 
                 7 
                 7, 5, 4 
                 — 
               
               
                 3 
                 — 
                 — 
                 7 
                 7, 6 
                 5, 6 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 4 
                 — 
                 — 
                 7 
                 7, 6 
                 5, 6 
                 — 
                 — 
                 7 
                 7, 4 
                 — 
               
               
                 5 
                 — 
                 — 
                 7 
                 7, 6 
                 5, 6 
                 — 
                 — 
                 7 
                 7, 5, 4 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 18 allow for uplink reporting from the association regions for configuration six  1341   g  described previously with respect to  FIG. 6 . For example, the second association region  1347   g  for configuration six  1341   g  captures the additional downlink subframe (e.g., subframe 7) for configuration three  1341   d , configuration four  1341   e  and configuration five  1341   f . As illustrated, the association regions  1347   g  for configuration six  1341   g  allow for uplink reporting of any of the other UL-DL configurations. 
       FIGS. 14-20  illustrate one example of a more evenly distributed mapping approach for each UL-DL configuration. In some cases, the association region mapping approach may result in unbalanced uplink reporting payloads. For example, if a PCell has configuration 3 and an SCell has configuration 2, then the number of ACK/NACK bits mapped from SCell are 5, 1 2 for uplink subframes 2, 3 and 4 respectively. In some cases, the unbalanced payload may limit the ability to effectively utilize the association region mapping approach. However, there are many other possible association mapping approaches. One possible approach may be a more evenly distributed mapping approach. The more evenly distributed mapping approach (e.g., distribution mapping) may define possible uplink reporting associations for more evenly distributed uplink reporting payloads. In one configuration, a distribution region may be defined for a reference configuration that identifies a region of uplink subframes that a set of subframes may be associated with in a more evenly balanced manner. The distribution regions may add new uplink reporting associations that balance the uplink reporting payloads. 
     The distribution mapping may be accomplished using a variety of possible associations. In one configuration, the unbalanced associations of the association region mapping approach may be redefined to provide a more evenly balanced distributed mapping. Several examples of distribution mapping are described herein. It should be noted that the terms “more evenly,” “balanced” and variations thereof may be used to mean that bits may be spread across a number of subframes in order to reduce disproportionality between subframes. It should be noted, however, that a “balanced” or “more even” distribution may not require an average number of bits per subframe. Rather, the bits may be more evenly distributed as compared to the “unbalanced” association region mapping approach in some cases. 
     It should be noted that different association mapping approaches may be used on different cells. For example, a first approach may be applied to one cell and a second approach may be applied to a second cell. Distribution regions may be described in further detail with reference to the Figures below. For convenience, distribution regions are indicated within dotted outlines. 
       FIG. 14  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration zero  1441   a  as applied to other configurations  1441   b - g . For convenience, possible associations  1449  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1439  may indicate corresponding subframes  1423 . In this example, two distribution regions  1451   a  may correspond to configuration zero  1441   a . A first distribution region  1451   a  for configuration zero  1441   a  includes uplink subframes 2, 3 and 4 and the second distribution region  1451   a  for configuration zero  1441   a  includes uplink subframes 7, 8 and 9. In configuration zero  1441   a  (e.g., the reference configuration), possible associations  1449  from subframes 6, 0, 1 and 5 are distributed between subframes  1423   a  within the first distribution region  1451   a  and the second distribution region  1451   a . As illustrated in  FIG. 14 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1423  within the distribution regions  1451   a . For example, in configuration three  1441   d , possible associations  1449  from subframes 6, 7, 8, 9, 0, 1 and 5 are balanced between the subframes  1423   d  within the distribution regions  1451   a  with subframes 6, 7 and 8 balanced within the first distribution region  1451   a  and with subframes 9, 0, 1 and 5 balanced within the second distribution region  1451   a . Table 19 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 19 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 0 (Ref. 
                 — 
                 — 
                 6 
                 — 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                 Cell) 
               
               
                 1 
                 — 
                 — 
                 6 
                 4 
                 4 
                 — 
                 — 
                 6 
                 4 
                 4 
               
               
                 2 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
               
               
                 3 
                 — 
                 — 
                 6 
                 6 
                 6 
                 — 
                 — 
                 8 
                 8, 7 
                 4 
               
               
                 4 
                 — 
                 — 
                 6, 5 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 4 
                 4 
               
               
                 5 
                 — 
                 — 
                 6, 5 
                 5, 4 
                 4 
                 — 
                 — 
                 6 
                 5, 4 
                 4 
               
               
                 6 
                 — 
                 — 
                 6 
                 4 
                 4 
                 — 
                 — 
                 6 
                 — 
                 4 
               
               
                   
               
            
           
         
       
     
       FIG. 15  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration one  1541   b  as applied to other configurations  1541   a ,  1541   c - g . For convenience, possible associations  1549  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1539  may indicate corresponding subframes  1523 . In this example, two distribution regions  1551   b  may correspond to configuration one  1541   b . A first distribution region  1551   b  for configuration one  1541   b  includes uplink subframes 2 and 3 and the second distribution region  1551   b  for configuration one  1541   b  includes uplink subframes 7 and 8. In configuration one  1541   b  (e.g., the reference configuration), possible associations  1549  from subframes 5, 6, 9, 0, 1 and 4 are distributed between subframes  1523   b  within the first distribution region  1551   b  and the second distribution region  1551   b . As illustrated in  FIG. 15 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1523  within the distribution regions  1551   b . For example, in configuration three  1541   d , possible associations  1549  from subframes 5, 6, 7, 8, 9, 0 and 1 are balanced between the subframes  1523   d  within the distribution regions  1551   b  with subframes 5, 6, 7 and 8 balanced within the first distribution region  1551   b  and with subframes 9, 0, and 1 balanced within the second distribution region  1551   b . Table 20 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 20 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 1 (Ref. 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
               
               
                 Cell) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 2 
                 — 
                 — 
                 7, 6 
                 5, 4 
                 — 
                 — 
                 — 
                 7, 6 
                 5, 4 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 — 
                 8, 7 
                 7 
                 — 
               
               
                 4 
                 — 
                 — 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 — 
                 8, 7 
                 4, 7 
                 — 
               
               
                 5 
                 — 
                 — 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 — 
                 8, 7 
                 5, 4, 7 
                 — 
               
               
                 6 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 16  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two  1641   c  as applied to other configurations  1641   a - b ,  1641   d - g . For convenience, possible associations  1649  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1639  may indicate corresponding subframes  1623 . In this example, two distribution regions  1651   c  may correspond to configuration two  1641   c . A first distribution region  1651   c  for configuration two  1641   c  includes uplink subframe 2 and the second distribution region  1651   c  for configuration two  1541   c  includes uplink subframe 7. In configuration two  1641   c  (e.g., the reference configuration), possible associations  1649  from subframes 4, 5, 6, 8, 9, 0, 1 and 3 are distributed between subframes  1623   c  within the first distribution region  1651   c  and the second distribution region  1651   c . As illustrated in  FIG. 16 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1623  within the distribution regions  1651   b . For example, in configuration three  1641   d , possible associations  1649  from subframes 5, 6, 7, 8, 9, 0 and 1 are balanced between the subframes  1623   d  within the distribution regions  1651   c  with subframes 5, 6, 7 and 8 balanced within the first distribution region  1651   c  and with subframes 9, 0 and 1 balanced within the second distribution region  1651   c . Table 21 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 21 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 (Ref. 
                 — 
                 — 
                 8, 7, 4, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 
                 — 
                 — 
               
               
                 Cell) 
                   
                   
                   
                   
                   
                   
                   
                 6 
               
               
                 0 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6, 5, 4 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7, 6, 5 
                 — 
                 — 
                 — 
                 — 
                 9, 8, 7, 
                 — 
                 — 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 6 
               
               
                 5 
                 — 
                 — 
                 8, 7, 6, 5, 4 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 4, 
                 — 
                 — 
               
               
                   
                   
                   
                   
                   
                   
                   
                   
                 6 
               
               
                 6 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 17  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration three  1741   c  as applied to other configurations  1741   a - c ,  1741   e - g . For convenience, possible associations  1749  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1739  may indicate corresponding subframes  1723 . In this example, one distribution region  1751   d  may correspond to configuration three  1741   d . A first distribution region  1751   d  for configuration three  1741   d  includes uplink subframes 2, 3 and 4. In configuration three  1741   d  (e.g., the reference configuration), possible associations  1749  from subframes 1, 5, 6, 7, 8, 9 and 0 are distributed between subframes  1723   d  within the first distribution region  1751   d . As illustrated in  FIG. 17 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1723  within the distribution regions  1751   d . For example, in configuration two  1741   c , possible associations  1749  from subframes 1, 3, 4, 5, 6, 8, 9 and 0 are balanced between the subframes  1723   d  within the distribution region  1751   d . Table 22 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 22 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 3 (Ref. 
                 — 
                 — 
                 7, 6, 11 
                 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
               
               
                 0 
                 — 
                 — 
                 11 
                 8, 7 
                 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 11, 8 
                 8, 7 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 11, 9, 8 
                 8, 5, 7 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 11, 8, 7 
                 7, 6, 5 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 11, 9, 8 
                 8, 7, 6 
                 6, 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 6 
                 — 
                 — 
                 11 
                 8, 7 
                 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 18  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration four  1841   e  as applied to other configurations  1841   a - d ,  1841   f - g . For convenience, possible associations  1849  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1839  may indicate corresponding subframes  1823 . In this example, a distribution region  1851   e  may correspond to configuration four  1841   e . A first distribution region  1851   e  for configuration four  1841   e  includes uplink subframes 2 and 3. In configuration four  1841   e  (e.g., the reference configuration), possible associations  1849  from subframes 0, 1, 4, 5, 6, 7, 8 and 9 are distributed between subframes  1823   e  within the first distribution region  1851   e . As illustrated in  FIG. 18 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1823  within the distribution region  1851   e . Table 23 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 23 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 4 (Ref. 
                 — 
                 — 
                 12, 8, 7, 11 
                 6, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
                   
                   
                   
                 7 
               
               
                 0 
                 — 
                 — 
                 12, 11 
                 8, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 12, 8, 11 
                 8, 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 12, 9, 8, 11 
                 8, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                   
                 7 
               
               
                 3 
                 — 
                 — 
                 12, 7, 6, 11 
                 6, 5, 4 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 12, 9, 8, 7, 
                 7, 6, 5, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 11 
                 4 
               
               
                 6 
                 — 
                 — 
                 12, 11 
                 8, 4, 7 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 19  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration five  1941   f  as applied to other configurations  1941   a - e ,  1941   g . For convenience, possible associations  1949  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  1939  may indicate corresponding subframes  1923 . In this example, one distribution region  1951   f  may correspond to configuration five  1941   f . A first distribution region  1951   f  for configuration five  1941   f  includes uplink subframe 2. In configuration five  1941   f  (e.g., the reference configuration), possible associations  1949  from subframes 9, 0, 1, 3, 4, 5, 6, 7 and 8 are distributed between subframes  1923   f  within the first distribution region  1951   f . As illustrated in  FIG. 19 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  1923  within the distribution region  1951   f . Table 24 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 24 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 5 (Ref. 
                 — 
                 — 
                 13, 12, 9, 8, 7, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 Cell) 
                   
                   
                 5, 4, 11, 6 
               
               
                 0 
                 — 
                 — 
                 12, 7, 11, 6 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 13, 12, 8, 7, 11, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 6 
               
               
                 2 
                 — 
                 — 
                 13, 12, 9, 8, 7, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 4, 11, 6 
               
               
                 3 
                 — 
                 — 
                 13, 12, 7, 5, 4, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 11, 6 
               
               
                 4 
                 — 
                 — 
                 13, 12, 8, 7, 5, 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
                   
                   
                 4, 11, 6 
               
               
                 6 
                 — 
                 — 
                 13, 12, 7, 11, 6 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 20  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration six  2041   g  as applied to other configurations  2041   a - f . For convenience, possible associations  2049  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  2039  may indicate corresponding subframes  2023 . In this example, two distribution regions  2051   g  may correspond to configuration six  2041   g . A first distribution region  2051   g  for configuration six  2041   g  includes uplink subframes 2, 3 and 4 and the second distribution region  2051   g  for configuration six  2041   g  includes uplink subframes 7 and 8. In configuration six  2041   g  (e.g., the reference configuration), possible associations  2049  from subframes 5, 6, 9, 0 and 1 are distributed between subframes  2023   g  within the first distribution region  2051   g  and the second distribution region  2051   g . As illustrated in  FIG. 20 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  2023  within the distribution regions  2051   g . For example, in configuration three  2041   d , possible associations  2049  from subframes 5, 6, 7, 8, 9, 0 and 1 are balanced between the subframes  2023   d  within the distribution regions  2051   g  with subframes 5, 6 and 7 balanced within the first distribution region  2051   g  and with subframes 8, 9, 0 and 1 balanced within the second distribution region  2051   g . Table 25 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 25 
               
             
            
               
                   
               
               
                 UL-DL 
                   
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 6 (Ref. 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 Cell) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7 
                 7 
                 — 
               
               
                 1 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7 
                 4, 7 
                 — 
               
               
                 2 
                 — 
                 — 
                 7 
                 5, 7 
                 5 
                 — 
                 — 
                 7, 6 
                 5, 4 
                 — 
               
               
                 3 
                 — 
                 — 
                 7 
                 7 
                 7 
                 — 
                 — 
                 9, 8 
                 8, 7 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7 
                 7 
                 7 
                 — 
                 — 
                 9, 8 
                 8, 7 
                 — 
               
               
                 5 
                 — 
                 — 
                 9, 8 
                 8, 7 
                 7 
                 — 
                 — 
                 9, 8 
                 8, 7 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 21  is a diagram illustrating two new superset uplink-downlink (UL-DL) configurations that may be used as reference cells in accordance with the systems and methods disclosed herein. In some cases, it may be beneficial to increase the number of uplink subframes that may be used. For example, increasing the number of uplink subframes may reduce the uplink reporting payload size. 
     In one configuration, the number of uplink subframes may be increased by using a combination of uplink subframes from some or all of the cells. In cases where multiple cells include uplink subframes during a particular subframe, the uplink subframe on the cell with the lowest Cell_ID may be used. For example, the uplink subframes of a PCell (e.g., Cell_ID=0) may be combined with the uplink subframes of one or more SCells. In this example, the PCell may be the uplink reporting cell for the uplink subframes in the PCell and an SCell (e.g., with a lowest Cell_ID for a particular subframe) may be the uplink reporting cell for any uplink subframes occurring on during a downlink subframe on the PCell. For instance, if configuration 2 and configuration 3 are both being used, then configuration 2 and configuration 3 may be combined to increase the number of uplink subframes. For instance, the cell with configuration 3 may be used as the uplink reporting cell for subframes 3, 4 and 5, and the cell with configuration 2 may be used as the uplink reporting cell for subframe 7. 
     Combining the uplink subframes from different UL-DL configurations may result in one or more superset UL-DL configurations. For example, the uplink subframes from configuration two and configuration three may be combined to form a superset UL-DL configuration that may be referred to as configuration two+three  2141   h  (e.g., “2+3”). In another example, the uplink subframes from configuration two and configuration four may be combined to form a superset UL-DL configuration that may be referred to as configuration two+four  2141   i  (e.g., “2+4”). In some cases, the superset UL-DL configurations may be used as a reference configuration. In one configuration, a reference cell may have a superset UL-DL configuration (e.g., configuration 2+3, configuration 2+4) as a reference configuration. In another configuration, a combination of uplink reporting cells may realize a superset UL-DL configuration (e.g., configuration 2+3, configuration 2+4). For instance, the uplink subframes from a first uplink reporting cell having configuration 2 and the uplink subframes from a second uplink reporting cell having configuration 3 may be combined to realize a superset reference configuration (e.g., configuration 2+3). In one configuration, both the first uplink reporting cell and the second uplink reporting cell may be reference cells. In another configuration, the reference cell may switch based on subframes. For instance, a cell with configuration 3 may be the reference cell for a number of subframes and then the reference cell may switch to a cell with configuration 2 for a number of subframes. 
     Configuration two+three  2141   h  and configuration two+four  2141   i  may be used as reference configurations for all of the systems and methods described herein. For example, association region mappings may be based on configuration two+three  2141   h  and configuration two+four  2141   i . In another example, more evenly distributed mappings may be based on configuration two+three  2141   h  and configuration two+four  2141   i.    
     Configuration two+three  2141   h  and configuration two+four  2141   i  are illustrated in  FIG. 21 . For convenience, possible associations  2145  that have been added based on the association region mappings may be indicated with dashed lines. Subframe numbers  2139  may indicate corresponding subframes  2123 . Configuration two+three  2141   h  includes four association regions  2147   h . A first association region  2147   h  for configuration two+three  2141   h  includes subframes 3, 4 and 5 and includes association mappings to the uplink subframe 2 in the next radio frame. The association from subframes 3, 4 and 5 to the uplink subframe 2 are new association mappings  2145  for configuration two+three  2141   h.    
     A second association region  2147   h  for configuration two+three  2141   h  includes subframes 6 and 7 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mappings from subframes 6 and 7 to the uplink subframe 3 are new association mappings  2145  for configuration two+three  2141   h.    
     A third association region  2147   h  for configuration two+three  2141   h  includes subframes 8 and 9 and includes an association mapping to the uplink subframe 4 in the next radio frame. The association from subframes 8 and 9 to the uplink subframe 4 are new association mappings  2145  for configuration two-three  2141   h.    
     A fourth association region  2147   h  for configuration two+three  2141   h  includes subframes 0 and 1 and includes an association mapping to the uplink subframe 7 in the current radio frame. The associations from subframes 0 and 1 to the uplink subframe 7 are new association mappings  2145  for configuration two+three  2141   h.    
     Configuration two+four  2141   i  includes three association regions  2147   i . A first association region  2147   i  for configuration two+four  2141   i  includes subframes 3, 4 and 5 and includes association mappings to the uplink subframe 2 in the next radio frame. The association from subframes 3, 4 and 5 to the uplink subframe 2 are new association mappings  2145  for configuration two+four  2141   i.    
     A second association region  2147   i  for configuration two+four  2141   i  includes subframes 6, 7 and 8 and includes association mappings to the uplink subframe 3 in the next radio frame. The association mappings from subframes 6, 7 and 8 to the uplink subframe 3 are new association mappings  2145  for configuration two+four  2141   i.    
     A third association region  2147   i  for configuration two+four  2141   i  includes subframes 9, 0 and 1 and includes an association mapping to the uplink subframe 7. The association from subframes 9, 0 and 1 to the uplink subframe 7 are new association mappings  2145  for configuration two-four  2141   i.    
       FIG. 22  illustrates more specifically the association regions for configuration two+three  2241   h  with respect to other uplink-downlink (UL-DL) configurations  2241   a - g . For example, the association regions  2247   h  illustrated in  FIG. 22  may be the same as the association regions  2147   h  illustrated in  FIG. 21  as applied to other UL-DL configurations  2241   a - g . The configurations  2241   a - h  in  FIG. 22  are illustrated as subframes  2223   a - h  with corresponding subframe numbers  2239   a - h . Table 26 below indicates the possible associations  2245  for configuration two+three  2241   h  (e.g., the reference configuration) for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 26 
               
             
            
               
                   
               
               
                 Superset 
                   
               
               
                 UL-DL 
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 + 3 
                 — 
                 — 
                 9, 8, 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 (Ref. Conf) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8, 7 
                 7 
                 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 9, 8, 7 
                 7 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 9, 8, 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 6 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The possible associations listed in Table 26 allow for uplink reporting from the association regions for configuration two+three  2241   h  described previously with respect to  FIG. 21 . For example, the first association region  2247   h  for configuration two+three  2241   h  captures the additional downlink subframes (e.g., subframes 3 and 4) for configuration one  2241   b , configuration two  2241   c , configuration four  2241   e  and configuration five  2241   f . As illustrated, the association regions  2247   h  for configuration two+three  2241   h  allow for uplink reporting of any of the other UL-DL configurations  2241   a - g.    
       FIG. 23  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two+three  2341   h  as applied to other configurations  2341   a - d . For convenience, possible associations  2349  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  2339  may indicate corresponding subframes  2323 . In this example, two distribution regions  2351   b  may correspond to configuration two+three  2341   h . A first distribution region  2351   h  for configuration two+three  2341   h  includes uplink subframes 2, 3 and 4 and the second distribution region  2351   h  for configuration two+three  2341   h  includes uplink subframe 7. Distribution regions  2351   h  may be based on configuration two+three  2341   h  (e.g., the reference configuration). As illustrated in  FIG. 23 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  2323  within the distribution regions  2351   h . For example, in configuration three  2341   d , possible associations  2349  from subframes 5, 6, 7, 8, 9, 0 and 1 are balanced between the subframes  2323   d  within the distribution regions  2351   h  with subframes 5, 6, 7, 8 and 9 balanced within the first distribution region  2351   h  and with subframes 0 and 1 balanced within the second distribution region  2351   h.    
       FIG. 24  is a diagram further illustrating the example set forth in  FIG. 23 . More specifically,  FIG. 24  illustrates an example of a more evenly distributed mapping approach for configuration two+three  2441   h  as applied to other configurations  2441   e - g . For convenience, possible associations  2449  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  2439  may indicate corresponding subframes  2423 . In this example, two distribution regions  2451   h  may correspond to configuration two+three  2341   h  as described previously. As illustrated in  FIG. 24 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  2423  within the distribution regions  2451   h  as described previously. Table 27 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. Table 27 corresponds with the diagrams in  FIGS. 23 and 24 . 
     
       
         
           
               
               
             
               
                 TABLE 27 
               
             
            
               
                   
               
               
                 Superset 
                   
               
               
                 UL-DL 
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 + 3 
                 — 
                 — 
                   
                   
                   
                 — 
                 — 
                   
                 — 
                 — 
               
               
                 (Ref. Conf) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 4 
                 — 
                 — 
                 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8 
                 8, 7 
                 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 9, 8 
                 8, 7 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 9, 8, 7 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 6 
                 — 
                 — 
                 7 
                 7 
                 5 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 25  illustrates more specifically the association regions for configuration two+four  2541   i  with respect to other uplink-downlink (UL-DL) configurations  2541   a - g . For example, the association regions  2547   i  illustrated in  FIG. 25  may be the same as the association regions  2147   i  illustrated in  FIG. 21  as applied to other UL-DL configurations  2541   a - g . The configurations  2541   a - g ,  2541   i  in  FIG. 25  are illustrated as subframes  2523   a - g ,  2523   i  with corresponding subframe numbers  2539   a - g ,  2539   i . Table 28 below indicates the possible associations  2545  for configuration two+four  2541   i  (e.g., the reference configuration) for aggregated uplink reporting of different UL-DL configurations. 
     
       
         
           
               
               
             
               
                 TABLE 28 
               
             
            
               
                   
               
               
                 Superset 
                   
               
               
                 UL-DL 
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 + 4 
                 — 
                 — 
                 9, 8, 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 (Ref. Conf) 
                   
                   
                 7 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8, 7 
                 7 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 9, 8, 
                 7, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
                   
                   
                 7 
               
               
                 3 
                 — 
                 — 
                 7 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 9, 8, 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
                   
                   
                 7 
               
               
                 6 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
     The added associations listed in Table 28 allow for uplink reporting from the association regions for configuration two+four  2541   i  described previously with respect to  FIG. 21 . For example, the first association region  2547   i  for configuration two+four  2541   i  captures the additional downlink subframes (e.g., subframe 3) for configuration three  2541   d  and configuration five  2541   f . As illustrated, the association regions  2547   i  for configuration two+four  2541   i  allow for uplink reporting of any of the other UL-DL configurations. 
       FIG. 26  is a diagram illustrating one example of a more evenly distributed mapping approach for configuration two+four  2641   i  as applied to other configurations  2641   a - d . For convenience, possible associations  2649  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  2639  may indicate corresponding subframes  2623 . In this example, two distribution regions  2651   i  may correspond to configuration two+four  2641   i . A first distribution region  2651   i  for configuration two+four  2641   i  includes uplink subframes 2 and 3 and the second distribution region  2651   i  for configuration two+four  2641   i  includes uplink subframe 7. Distribution regions  2651   i  may be based on configuration two+four  2641   i  (e.g., the reference configuration). As illustrated in  FIG. 26 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  2623  within the distribution regions  2651   i . For example, in configuration three  2641   d , possible associations  2649  from subframes 5, 6, 7, 8, 9, 0 and 1 are distributed between the subframes  2623   d  within the distribution regions  2651   i  with subframes 5, 6, 7 and 8 distributed within the first distribution region  2651   i  and with subframes 9, 0 and 1 distributed within the second distribution region  2651   i.    
       FIG. 27  is a diagram further illustrating the example set forth in  FIG. 26 . More specifically,  FIG. 27  illustrates an example of a more evenly distributed mapping approach for configuration two+four  2741   i  as applied to other configurations  2741   e - g . For convenience, possible associations  2749  that have been added based on the distribution region mappings may be indicated with solid lines. Subframe numbers  2739  may indicate corresponding subframes  2723 . In this example, two distribution regions  2751   i  may correspond to configuration two+four  2741   i  as described previously. As illustrated in  FIG. 27 , the uplink reporting associations for each of the reporting subframes in each of the UL-DL configurations may be distributed between subframes  2723  within the distribution regions  2751   i  as described previously. Table 29 below summarizes one example of distribution mapping associations for each of the UL-DL configurations. Table 29 corresponds with the diagrams in  FIGS. 26 and 27 . 
     
       
         
           
               
               
             
               
                 TABLE 29 
               
             
            
               
                   
               
               
                 Superset 
                   
               
               
                 UL-DL 
               
               
                 Configu- 
                 Subframe n 
               
            
           
           
               
               
               
               
               
               
               
               
               
               
               
            
               
                 ration 
                 0 
                 1 
                 2 
                 3 
                 4 
                 5 
                 6 
                 7 
                 8 
                 9 
               
               
                   
               
               
                 2 + 4 
                 — 
                 — 
                   
                   
                 — 
                 — 
                 — 
                   
                 — 
                 — 
               
               
                 (Ref. Conf) 
               
               
                 0 
                 — 
                 — 
                 7 
                 7 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 1 
                 — 
                 — 
                 8, 7 
                 7, 4 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                 2 
                 — 
                 — 
                 9, 8 
                 8, 5, 7 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 3 
                 — 
                 — 
                 7, 6 
                 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 4 
                 — 
                 — 
                 8, 7 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                 5 
                 — 
                 — 
                 9, 8, 
                 7, 6, 5 
                 — 
                 — 
                 — 
                 8, 7, 6 
                 — 
                 — 
               
               
                   
                   
                   
                 7 
               
               
                 6 
                 — 
                 — 
                 7, 6 
                 4 
                 — 
                 — 
                 — 
                 7, 6 
                 — 
                 — 
               
               
                   
               
            
           
         
       
     
       FIG. 28  is a flow diagram illustrating one configuration of a method  2800  for selecting a reference cell on a UE  102 . The UE  102  may determine  2802  at least one cell with a smallest periodicity. For example, as described previously, some UL-DL configurations may have 5 ms periodicity and some UL-DL configurations may have 10 ms periodicity. In the case that some of the cells have 5 ms periodicity and some of the cells have 10 ms periodicity, then a cell with a smallest periodicity may be a cell with 5 ms periodicity. In the case that all of the cells have 10 ms periodicity, then a cell with a smallest periodicity will be a cell with 10 ms periodicity. In the case that all of the cells have 5 ms periodicity, then a cell with a smallest periodicity may be a cell with 5 ms periodicity. 
     The UE  102  may determine  2804  whether there is more than one cell with a smallest periodicity. If there is only one cell with the smallest periodicity (e.g., not more than one), then the UE  102  may use  2806  (e.g., designate) the cell with the smallest periodicity as the reference cell. If there is more than one cell with the smallest periodicity, then the UE  102  may determine  2808  at least one cell with a highest uplink allocation. The UE  102  may determine  2808  the cell with a highest uplink allocation from among the more than one cells determined  2802  to have a smallest periodicity. In one configuration, the UE  102  may determine  2808  at least one cell with a highest uplink allocation by comparing the number of uplink subframes. For example, configuration 0 includes six uplink subframes for each radio frame and configuration 6 includes five uplink subframes for each radio frame. In this example, between a cell with configuration 0 and a cell with configuration 6, the cell with configuration 0 may have the highest uplink allocation. Selecting a cell with the highest uplink allocation may be beneficial because the higher the uplink allocation, the more uplink subframes that associations may be distributed among. This may reduce or minimize the number of allocations per uplink subframe, which may reduce the size of uplink reporting payloads. 
     The UE  102  may determine  2810  whether there is more than one cell with a highest uplink allocation. If there is only one cell with a highest uplink allocation (e.g., not more than one), then the UE  102  may use  2812  (e.g., designate) the cell with the highest uplink allocation as the reference cell. If there is more than one cell with a highest periodicity, then the UE  102  may determine  2814  the cell with a lowest cell index (Cell_ID). The UE  102  may determine  2814  the cell with the lowest Cell_ID from among the more than one cells determined  2808  to have a highest uplink allocation. Each cell may have a Cell_ID. Therefore, the cell with the lowest Cell_ID may be determined  2814  by comparing Cell_ID values. The UE  102  may use  2816  (e.g., designate) the cell with the lowest cell index (Cell_ID) as the reference cell. 
     In one configuration, method  2800  may be used to select a reference cell based on the UL-DL configuration of each cell (selecting a reference cell any time there may be a change in cells or UL-DI configuration of a cell, for example). Once the reference cell is selected, the reference cell may be used to carry uplink ACK/NACK reporting. In another configuration, the method  2800  may be used to select a reference cell to decide the reference cell configuration. However, the actual uplink reporting may be based on each uplink subframe occurring on any of the cells. For example, the PCell may be the uplink reporting cell for some uplink subframes in the reference cell configuration, but if an SCell includes an uplink subframe when the PCell has a downlink subframe, then the uplink subframe on the SCell with the lowest Cell_ID may be selected as the uplink reporting cell for that particular subframe in the reference cell configuration. 
       FIG. 29  illustrates various components that may be utilized in a user equipment (UE)  2902 . The UE  2902  may be utilized as the UE  102  described above. The UE  2902  includes a processor  2963  that controls operation of the UE  2902 . The processor  2963  may also be referred to as a central processing unit (CPU). Memory  2969 , which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions  2965   a  and data  2967   a  to the processor  2963 . A portion of the memory  2969  may also include non-volatile random access memory (NVRAM). Instructions  2965   b  and data  2967   b  may also reside in the processor  2963 . Instructions  2965   b  and/or data  2967   b  loaded into the processor  2963  may also include instructions  2965   a  and/or data  2967   a  from memory  2969  that were loaded for execution or processing by the processor  2963 . The instructions  2965   b  may be executed by the processor  2963  to implement one or more of the methods  200  and  2800  described above. 
     The UE  2902  may also include a housing that contains one or more transmitters  2958  and one or more receivers  2920  to allow transmission and reception of data. The transmitter(s)  2958  and receiver(s)  2920  may be combined into one or more transceivers  2918 . One or more antennas  2922   a - n  are attached to the housing and electrically coupled to the transceiver  2918 . 
     The various components of the UE  2902  are coupled together by a bus system  2971 , which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in  FIG. 29  as the bus system  2971 . The UE  2902  may also include a digital signal processor (DSP)  2973  for use in processing signals. The UE  2902  may also include a communications interface  2975  that provides user access to the functions of the UE  2902 . The UE  2902  illustrated in  FIG. 29  is a functional block diagram rather than a listing of specific components. 
       FIG. 30  illustrates various components that may be utilized in an evolved Node B (eNB)  3060 . The eNB  3060  may be utilized as the eNB  160  described above. The eNB  3060  includes a processor  3077  that controls operation of the eNB  3060 . The processor  3077  may also be referred to as a central processing unit (CPU). Memory  3083 , which may include read-only memory (ROM), random access memory (RAM), a combination of the two or any type of device that may store information, provides instructions  3079   a  and data  3081   a  to the processor  3077 . A portion of the memory  3083  may also include non-volatile random access memory (NVRAM). Instructions  3079   b  and data  3081   b  may also reside in the processor  3077 . Instructions  3079   b  and/or data  3081   b  loaded into the processor  3077  may also include instructions  3079   a  and/or data  3081   a  from memory  3083  that were loaded for execution or processing by the processor  3077 . The instructions  3079   b  may be executed by the processor  3077  to implement the method  300  described above. 
     The eNB  3060  may also include a housing that contains one or more transmitters  3017  and one or more receivers  3078  to allow transmission and reception of data. The transmitter(s)  3017  and receiver(s)  3078  may be combined into one or more transceivers  3076 . One or more antennas  3080   a - n  are attached to the housing and electrically coupled to the transceiver  3076 . 
     The various components of the eNB  3060  are coupled together by a bus system  3085 , which may include a power bus, a control signal bus and a status signal bus, in addition to a data bus. However, for the sake of clarity, the various buses are illustrated in  FIG. 30  as the bus system  3085 . The eNB  3060  may also include a digital signal processor (DSP)  3087  for use in processing signals. The eNB  3060  may also include a communications interface  3089  that provides user access to the functions of the eNB  3060 . The eNB  3060  illustrated in  FIG. 30  is a functional block diagram rather than a listing of specific components. 
     The term “computer-readable medium” refers to any available medium that can be accessed by a computer or a processor. The term “computer-readable medium,” as used herein, may denote a computer- and/or processor-readable medium that is non-transitory and tangible. By way of example, and not limitation, a computer-readable or processor-readable medium may comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer or processor. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and Blu-ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. 
     It should be noted that one or more of the methods described herein may be implemented in and/or performed using hardware. For example, one or more of the methods described herein may be implemented in and/or realized using a chipset, an application-specific integrated circuit (ASIC), a large-scale integrated circuit (LSI) or integrated circuit, etc. 
     Each of the methods disclosed herein comprises one or more steps or actions for achieving the described method. The method steps and/or actions may be interchanged with one another and/or combined into a single step without departing from the scope of the claims. In other words, unless a specific order of steps or actions is required for proper operation of the method that is being described, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims. 
     It is to be understood that the claims are not limited to the precise configuration and components illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the systems, methods, and apparatus described herein without departing from the scope of the claims.