Patent Publication Number: US-2013242751-A1

Title: Method and apparatus for handling dci (downlink control information) format size

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/610,193 filed on Mar. 13, 2012 the entire disclosure of which is incorporated herein by reference. 
    
    
     FIELD 
     This disclosure generally relates to wireless communication networks, and more particularly, to a method and apparatus for handling DCI (Downlink Control Information) format size. 
     BACKGROUND 
     With the rapid rise in demand for communication of large amounts of data to and from mobile communication devices, traditional mobile voice communication networks are evolving into networks that communicate with Internet Protocol (IP) data packets. Such IP data packet communication can provide users of mobile communication devices with voice over IP, multimedia, multicast and on-demand communication services. 
     An exemplary network structure for which standardization is currently taking place is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The E-UTRAN system can provide high data throughput in order to realize the above-noted voice over IP and multimedia services. The E-UTRAN system&#39;s standardization work is currently being performed by the 3GPP standards organization. Accordingly, changes to the current body of 3GPP standard are currently being submitted and considered to evolve and finalize the 3GPP standard. 
     SUMMARY 
     A method and apparatus are disclosed for handling DCI (Downlink Control Information) format size. The method includes configuring a UE (User Equipment) with one or more carrier segment(s). The method also includes deriving a size of a resource assignment field for a first PDCCH (Physical Downlink Control Channel) from a bandwidth configuration of a backward compatible carrier and a bandwidth of the carrier segment(s). The method further includes deriving a size of a resource assignment field for a second PDCCH from the bandwidth configuration of the backward compatible carrier and not from the bandwidth of the carrier segment(s). In one embodiment, the method also includes deriving a fixed size resource block assignment field in a RAR (Random Access Response) grant based on a UL bandwidth configuration of the backward compatible carrier without taking the bandwidth of carrier segment(s) on the UL into account. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a diagram of a wireless communication system according to one exemplary embodiment. 
         FIG. 2  is a block diagram of a transmitter system (also known as access network) and a receiver system (also known as user equipment or UE) according to one exemplary embodiment. 
         FIG. 3  is a functional block diagram of a communication system according to one exemplary embodiment. 
         FIG. 4  is a functional block diagram of the program code of  FIG. 3  according to one exemplary embodiment. 
         FIG. 5  is a flow chart according to one exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The exemplary wireless communication systems and devices described below employ a wireless communication system, supporting a broadcast service. Wireless communication systems are widely deployed to provide various types of communication such as voice, data, and so on. These systems may be based on code division multiple access (CDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), 3GPP LIE (Long Term Evolution) wireless access, 3GPP LTE-A or LTE-Advanced (Long Term Evolution Advanced), 3GPP2 UMB (Ultra Mobile Broadband), WiMax, or some other modulation techniques. 
     In particular, the exemplary wireless communication systems devices, described below may be designed to support one or more standards such as the standard offered by a consortium named “3rd Generation Partnership Project” referred to herein as 3GPP, including Document Nos. 3GPP TS 36.321 V10.4.0, “E-UTRA; MAC protocol specification”; R1-100038, “On definitions of carrier types”; RP-111115, “LTE Carrier Aggregation Enhancements WID”; R2-115666, “LS on additional carrier types for CA enhancement”; TS 36.331 V10.4.0, “E-UTRA; RRC protocol specification”; TS 36.212 V10.4.0, “E-UTRA Multiplexing and channel coding (Release 10)”; TS 36.213 V10.4.0, “E-UTRA Physical layer procedures (Release 10)”. The standards and documents listed above are hereby expressly incorporated herein. 
       FIG. 1  shows a multiple access wireless communication system according to one embodiment of the invention. An access network  100  (AN) includes multiple antenna groups, one including  104  and  106 , another including  108  and  110 , and an additional including  112  and  114 . In  FIG. 1 , only two antennas are shown for each antenna group, however, more or fewer antennas may be utilized for each antenna group. Access terminal  116  (AT) is in communication with antennas  112  and  114 , where antennas  112  and  114  transmit information to access terminal  116  over forward link  120  and receive information from access terminal  116  over reverse link  118 . Access terminal (AT)  122  is in communication with antennas  106  and  108 , where antennas  106  and  108  transmit information to access terminal (AT)  122  over forward link  126  and receive information from access terminal (AT)  122  over reverse link  124 . In a FDD system, communication links  118 ,  120 ,  124  and  126  may use different frequency for communication. For example, forward link  120  may use a different frequency then that used by reverse link  118 . 
     Each group of antennas and/or the area in which they are designed to communicate is often referred to as a sector of the access network. In the embodiment, antenna groups each are designed to communicate to access terminals in a sector of the areas covered by access network  100 . 
     In communication over forward links  120  and  126 , the transmitting antennas of access network  100  may utilize beamforming in order to improve the signal-to-noise ratio of forward links for the different access terminals  116  and  122 . Also, an access network using beamforming to transmit to access terminals scattered randomly through its coverage causes less interference to access terminals in neighboring cells than an access network transmitting through a single antenna to all its access terminals. 
     An access network (AN) may be a fixed station or base station used for communicating with the terminals and may also be referred to as an access point, a Node B, a base station, an enhanced base station, an eNodeB, or some other terminology. An access terminal (AT) may also be called user equipment (UE), a wireless communication device, terminal, access terminal or some other terminology. 
       FIG. 2  is a simplified block diagram of an embodiment of a transmitter system  210  (also known as the access network) and a receiver system  250  (also known as access terminal (AT) or user equipment (UE)) in a MIMO system  200 . At the transmitter system  210 , traffic data for a number of data streams is provided from a data source  212  to a transmit (TX) data processor  214 . 
     In one embodiment, each data stream is transmitted over a respective transmit antenna. TX data processor  214  formats, codes, and interleaves the traffic data for each data stream based on a particular coding scheme selected for that data stream to provide coded data. 
     The coded data for each data stream may be multiplexed with pilot data using OFDM techniques. The pilot data is typically a known data pattern that is processed in a known manner and may be used at the receiver system to estimate the channel response. The multiplexed pilot and coded data for each data stream is then modulated (i.e., symbol mapped) based on a particular modulation scheme (e.g., BPSK, QPSK, M-PSK, or M-QAM) selected for that data stream to provide modulation symbols. The data rate, coding, and modulation for each data stream may be determined by instructions performed by processor  230 . 
     The modulation symbols for all data streams are then provided to a TX MIMO processor  220 , which may further process the modulation symbols (e.g., for OFDM), TX MIMO processor  220  then provides N T  modulation symbol streams to N T  transmitters (TMTR)  222   a  through  222   t . In certain embodiments, TX MIMO processor  220  applies beamforming weights to the symbols of the data streams and to the antenna from which the symbol is being transmitted. 
     Each transmitter  222  receives and processes a respective symbol stream to provide one or more analog signals, and further conditions (e.g., amplifies, filters, and upconverts) the analog signals to provide a modulated signal suitable for transmission over the MIMO channel. N T  modulated signals from transmitters  222   a  through  222   t  are then transmitted from N T  antennas  224   a  through  224   t , respectively. 
     At receiver system  250 , the transmitted modulated signals are received by N R  antennas  252   a  through  252   r  and the received signal from each antenna  252  is provided to a respective receiver (RCVR)  254   a  through  254   r . Each receiver  254  conditions (e.g., filters, amplifies, and downconverts) a respective received signal, digitizes the conditioned signal to provide samples, and further processes the samples to provide a corresponding “received” symbol stream. 
     An RX data processor  260  then receives and processes the N R  received symbol streams from N R  receivers  254  based on a particular receiver processing technique to provide N T  “detected” symbol streams. The RX data processor  260  then demodulates, deinterleaves, and decodes each detected symbol stream to recover the traffic data for the data stream. The processing by RX data processor  260  is complementary to that performed by TX MIMO processor  220  and TX data processor  214  at transmitter system  210 . 
     A processor  270  periodically determines which pre-coding matrix to use (discussed below). Processor  270  formulates a reverse link message comprising a matrix index portion and a rank value portion. 
     The reverse link message may comprise various types of information regarding the communication link and/or the received data stream. The reverse link message is then processed by a TX data processor  238 , which also receives traffic data for a number of data streams from a data source  236 , modulated by a modulator  280 , conditioned by transmitters  254   a  through  254   r , and transmitted back to transmitter system  210 . 
     At transmitter system  210 , the modulated signals from receiver system  250  are received by antennas  224 , conditioned by receivers  222 , demodulated by a demodulator  240 , and processed by a RX data processor  242  to extract the reserve link message transmitted by the receiver system  250 . Processor  230  then determines which pre-coding matrix to use for determining the beamforming weights then processes the extracted message. 
     Turning to  FIG. 3 , this figure shows an alternative simplified functional block diagram of a communication device according to one embodiment of the invention. As shown in  FIG. 3 , the communication device  300  in a wireless communication system can be utilized for realizing the UEs (or ATs)  116  and  122  in  FIG. 1 , and the wireless communications system is preferably the LTE system. The communication device  300  may include an input device  302 , an output device  304 , a control circuit  306 , a central processing unit (CPU)  308 , a memory  310 , a program code  312 , and a transceiver  314 . The control circuit  306  executes the program code  312  in the memory  310  through the CPU  308 , thereby controlling an operation of the communications device  300 . The communications device  300  can receive signals input by a user through the input device  302 , such as a keyboard or keypad, and can output images and sounds through the output device  304 , such as a monitor or speakers. The transceiver  314  is used to receive and transmit wireless signals, delivering received signals to the control circuit  306 , and outputting signals generated by the control circuit  306  wirelessly. 
       FIG. 4  is a simplified block diagram of the program code  312  shown in  FIG. 3  in accordance with one embodiment of the invention. In this embodiment, the program code  312  includes an application layer  400 , a Layer 3 portion  402 , and a Layer 2 portion  404 , and is coupled to a Layer 1 portion  406 . The Layer 3 portion  402  generally performs radio resource control. The Layer 2 portion  404  generally performs link control. The Layer 1 portion  406  generally performs physical connections. 
     Carrier aggregation (CA) is generally a feature to support wider bandwidth in LTE-Advanced (LTE-A). A terminal may simultaneously receive or transmit on one or multiple component carriers depending on its capabilities. 
     In addition to a primary serving cell (Pcell), a UE in RRC_CONNECTED mode may be configured with other secondary serving cells (Scell). Both Pcell and Scell are backward compatible carriers. The Pcell is typically considered as always activated, while an Activation/Deactivation MAC Control Element (CE) could be used to activate or deactivate an Scell (as discussed in 3GPP TS 36.321 V10.4.0). A sCellDeactivationTimer corresponding to the Scell may also be used for Scell status maintenance (e.g., when the sCellDeactivationTimer expires), the corresponding Scell is implicitly considered as deactivated. 
     Besides backward compatible carriers, 3GPP R1-100038 also defines two following additional carrier types in Rel-10: 
     
       
         
           
               
             
               
                   
               
               
                 Properties of extension carriers: 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 Supported by carrier aggregation 
               
               
                 Non-backwards compatible carrier 
               
               
                 Transmission bandwidth is at least from the set of existing values, i.e., 
               
               
                 {6, 15, 25, 50, 75, 100} RBs. Other transmission bandwidths may be 
               
               
                 defined by RAN4. 
               
               
                 The sum of backward compatible component carrier and extension carrier 
               
               
                 can be more than 110 RBs. 
               
               
                 Separate PDCCH indicates the RBs defined within the extension carrier. 
               
               
                 It is FFS whether the linkage between backward compatible component 
               
               
                 carrier and extension carrier is per UE. 
               
               
                 Separate HARQ process running within an extension carrier. 
               
               
                 Backward compatible component carrier (to which the extension carrier 
               
               
                 is linked to) and the extension carrier can be configured with different 
               
               
                 transmission modes. 
               
               
                 Extension carriers configuration without CRS is FFS. 
               
               
                 Extension carriers can be configured as contiguous or as non-contiguous 
               
               
                 to the backwards compatible component carrier they are linked to. 
               
               
                   
               
            
           
         
       
     
     
       
         
           
               
             
               
                   
               
               
                 Properties of carrier segments: 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
            
               
                 Not necessary to have carrier aggregation. 
               
               
                 Used to enable additional transmission bandwidths beyond the set of Rel-8 
               
               
                 values, i.e., {6, 15, 25, 50, 75, 100} RBs but no more than 110 RBs. 
               
               
                 What sets are used is defined by RAN4. 
               
               
                 The sum of backward compatible component carrier and segment(s) shall 
               
               
                 be no more than 110RBs. Configurations with sum of backwards 
               
               
                 compatible component carrier and segment(s) over 110RBs are FFS. 
               
               
                 One PDCCH indicates the RBs allocated in the sum of backward 
               
               
                 compatible carrier and segment(s). 
               
               
                 One HARQ process for the sum of backward compatible carrier and 
               
               
                 segment(s). 
               
               
                 Backward compatible component carrier and segment(s) use the same 
               
               
                 transmission mode. 
               
               
                 Segments configuration without CRS is FFS. 
               
               
                 Segments are contiguous to the component carrier they are associated 
               
               
                 with. 
               
               
                   
               
            
           
         
       
     
     However, discussion on additional carrier types was postponed to Rel-11 due to time limit for Rel-10. As discussed in 3GPP RP-111115, a new work item of LTE Carrier Aggregation (CA) Enhancements re-opens the discussion on additional carrier types. 3GPP R2-115666 is a liaison (LS) on additional carrier types for CA enhancement that includes the following conclusion and working assumptions: 
     Conclusion: 
     
         
         
           
             From a RAN1 perspective, the main motivations identified for introducing a new carrier type for carrier aggregation are:
           energy efficiency   Enhanced spectral efficiency   Improved support for het net   
         
             It is for RAN4 to determine whether there is a need for new RF bandwidths to support improved bandwidth scalability. 
           
         
       
    
     Working Assumptions: 
     
         
         
           
             Introduce at least one new carrier type in Rel-141 (bandwidth agnostic/unknown from a RAN1 point of view), with at least reduced or eliminated legacy control signalling and/or CRS
           at least for the downlink (or for TDD, the downlink subframes on a carrier)   associated with a backward compatible carrier   study further:
               issues of synchronisation/tracking (including whether or not PSS/SSS are transmitted) and measurements/mobility   resource allocation methods   what RSs are required   
               
         
             For FDD a downlink carrier of the new type may be linked with a legacy uplink carrier, and for TDD a carrier may contain downlink subframes of the new type and legacy uplink subframes. 
           
         
       
    
     Note that the current scope of the WI is for CA. 
     Uplink enhancements are not precluded. 
     For carrier segment(s), one PDCCH (Physical Downlink Control Channel) could indicate the RBs (Resource Block) allocated in the sum of backward compatible carrier and carrier segment(s). Since the payload size of resource block assignment field in PDCCH depends on the DL/UL (Downlink/Uplink) bandwidth size (as discussed in 3GPP TS 36.212 V10.4.0), the size of Downlink Control Information (DCI) format may be increased after carrier segment(s) is configured for a UE. Since the usage of carrier segment(s) is known on both network and UE sides, there seems to be no problem. However, regarding the contention based random access, network could not know whether the UE sending preamble would be configured with carrier Segment or not. The size of DCI format indicating Random Access Response (RAR) may be unsynchronized. 
     For UL grant included in RAR (as discussed in 3 GPP TS 36.213 V10.4.0), even though the resource block assignment field has fixed size, the interpretation size may be unsynchronized between network and UE configured with carrier segment(s) depending on UL bandwidth. 
     Since the carrier segment(s) could let UE utilize additional resources other than the backward compatible carrier, the PDCCH may require more bits to assign resource blocks for transmission. In case of contention based random access, one potential solution would be to keep the payload size of the PDCCH indicating RAR (Random Access Response) the same regardless of whether the carrier segment(s) is configured for a UE or not. This means that the resource block assignment field would be derived from DL bandwidth configuration of the backward compatible carrier and not from the bandwidth of carrier segment(s) on DL. Thus, the PDCCH indicating RAR flit a UE configured with carrier segment(s) on DL would have the same payload site as that for a UE not configured with carrier segment(s). Furthermore, the derivation of the fixed size resource block assignment field in the RAR grant would be based on the UL bandwidth configuration of the backward compatible carrier and not on carrier segment(s) on UL to avoid different interpretation. In addition, the potential solution could be applied to contention free random access for consistent behavior. 
     Also, since the carrier segment(s) is attached to a backward compatible carrier, it would be better to transmit system information and paging within the bandwidth of the backward compatible carrier. Accordingly, another potential solution is to constrain the derivation of resource block assignment field such that the carrier segment(s) would not be taken into account if the PDCCH is given in the common search space. 
     Currently, segment configuration without CRS (Cell specific Reference Signal) is FFS (For Future Study). Assuming there is no CRS in carrier segment(s), the DCI (Downlink Control Information) format 1A, for indicating fallback mode transmission, would not assign the resource blocks in carrier segment(s). Considering the DCI format 1A could assign not only RAR but also fallback mode transmission, there could be one more potential solution to constrain the derivation of resource block assignment field such that the carrier segment(s) on DL would not be taken into account if the DCI format of PDCCH is DCI format 1A/1C. 
       FIG. 5  is a flow chart  500  according to one exemplary embodiment. In step  505 , a UE is configured with one or more carrier segment(s). In step  510 , the size of a resource assignment field for a first PDCCH is derived from a bandwidth configuration of a backward compatible carrier and a bandwidth of the carrier segment(s). 
     In one embodiment, the bandwidth configuration of the backward compatible carrier would be a DL (Downlink) bandwidth configuration, N RB   DL , if the UE is configured with carrier segment(s) on a DL. Furthermore, the size of the resource block assignment field for the first PDCCH is derived from the summation of the bandwidth configuration of the backward compatible carrier and the bandwidth of carrier segment(s) via a formula. In one embodiment, the formula would be ┌(N RB   DL +N RB   DL     —     seg )/P┐ where P is the resource block group size and N RB   DL     —     seg  is the bandwidth of configured carrier segment(s) on the DL. In an alternative embodiment, the formula would be ┌log 2 ((N RB   DL +N RB   DL     —     seg )(N RB   DL +N RB   DL     —     seg 1)/2)┐ where D RB   DL     —     seg  is the bandwidth of configured carrier segment(s) on the DL. 
     In addition, if the UE is configured with carrier segment(s) on a UL (Uplink), the bandwidth configuration the bandwidth configuration of the backward compatible carrier would be a UL (Uplink) bandwidth configuration, N RB   UL . Furthermore, the size of the resource block assignment field for the first PDCCH is derived from a summation of the bandwidth configuration of the backward compatible carrier and the bandwidth of carrier segment(s) via a formula. In one embodiment, the formula would be 
     
       
         
           
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     where P is the resource block group size and N RB   UL     —     seg  is the bandwidth of configured carrier segment(s) on the UL. In an alternative embodiment, the formula would be ┌log 2 ((N RB   UL +N RB   UL     —     seg )(N RB   UL +N RB   UL     —     seg +1)/2)┐ where N RB   UL     —     seg  is the bandwidth of configured carrier segment(s) on the UL. 
     Returning to  FIG. 5 , in step  515 , a size of a resource assignment field for a second PDCCH is derived from a bandwidth configuration of a backward compatible carrier and not from a bandwidth of the carrier segment(s). In one embodiment, the CRC (Cyclic Redundancy Check) of the first PDCCH could be scrambled by C-RNTI (Cell-Radio Network Temporary Identifier) or SPS (Semi-Persistent. Scheduling) C-RNTI. Furthermore, the CRC of the second PDCCH could be scrambled by RA-RNTI (Random Access RNTI). Also, the PDCCH with CRC scrambled by RA-RNTI could assign the transmission of the RAR. 
     In step  520  of  FIG. 5 , a fixed size resource block assignment field in as RAR grant is derived based on a UL bandwidth configuration of the backward compatible carrier without taking the bandwidth of carrier segment(s) on the UL in account. In one embodiment, the UE attempts to receive the RAR according to the transmission of a random access preamble that the UE has selected (for a contention-based random access) or has not selected (for a contention-free random access). 
     Referring back to  FIGS. 3 and 4 , the UE  300  includes a program code  312  stored in memory  310 . In one embodiment, the CPU  308  could execute the program code  312  to (i) configure a UE (User Equipment) with one or more carrier segment(s), (ii) derive a size of a resource assignment field for a first PDCCH (Physical Downlink Control Channel) from a bandwidth configuration of a backward compatible carrier and a bandwidth of the carrier segment(s), and (iii) derive a size of a resource assignment field for a second PDCCH from the bandwidth configuration of the backward compatible carrier and not from the bandwidth of the carrier segment(s). Furthermore, the CPU  308  could execute the program code  312  to derive a fixed size resource block assignment field in a RAR grant based on a UL bandwidth configuration of the backward compatible carrier without taking the bandwidth of carrier segment(s) on the UL in account. 
     In one embodiment, the first PDCCH could be monitored by a UE in UE specific search space, while the second PDCCH could be monitored by a UE in a common search space. In this embodiment, the DCI format of the first PDCCH could be DCI format 1, 1B, 1D, 2, 2A, 2B, 2C, or 4, while the DCI format of the second PDCCH could be DCI format 1A or 1C. 
     In addition, the CPU  308  can execute the program code  312  to perform all of the above-described actions and steps or others described herein. 
     Various aspects of the disclosure have been described above. It should be apparent that the teachings herein may be embodied in a wide variety of forms and that any specific structure, function, or both being disclosed herein is merely representative. Based on the teachings herein one skilled in the art should appreciate that an aspect disclosed herein may be implemented independently of any other aspects and that two or more of these aspects may be combined in various ways. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, such an apparatus may be implemented or such a method may be practiced using other structure, functionality, or structure and functionality in addition to or other than one or more of the aspects set forth herein. As an example of some of the above concepts, in some aspects concurrent channels may be established based on pulse repetition frequencies. In some aspects concurrent channels may be established based on pulse position or offsets. In some aspects concurrent channels may be established based on time hopping sequences. In some aspects concurrent channels may be established based on pulse repetition frequencies, pulse positions or offsets, and time hopping sequences. 
     Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof. 
     Those of skill would further appreciate that the various illustrative logical blocks, modules, processors, means, circuits, and algorithm steps described in connection with the aspects disclosed herein may be implemented as electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two, which may be designed using source coding or some other technique), various forms of program or design code incorporating instructions (which may be referred to herein, for convenience, as “software” or a “software module”), or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present disclosure. 
     In addition, the various illustrative logical blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented within or performed by an integrated circuit (“IC”), an access terminal, or an access point. The IC may comprise a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, electrical components, optical components, mechanical components, or any combination thereof designed to perform the functions described herein, and may execute codes or instructions that reside within the IC, outside of the IC, or both. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. 
     It is understood that any specific order or hierarchy of steps in any disclosed process is an example of a sample approach. Based upon design preferences, it is understood that the specific order or hierarchy of steps in the processes may be rearranged while remaining within the scope of the present disclosure. The accompanying method claims present elements of the various steps in a sample order, and are not meant to be limited to the specific order or hierarchy presented. 
     The steps of a method or algorithm described in connection with the aspects disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module (e.g., including executable instructions and related data) and other data may reside in a data memory such as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of computer-readable storage medium known in the art. A sample storage medium may be coupled to a machine such as, for example, a computer/processor (which may be referred to herein, for convenience, as a “processor”) such the processor can read information (e.g., code) from and write information to the storage medium. A sample storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ARC may reside in user equipment. In the alternative, the processor and the storage medium may reside as discrete components in user equipment. Moreover, in some aspects any suitable computer-program product may comprise a computer-readable medium comprising codes relating to one or more of the aspects of the disclosure. In some aspects a computer program product may comprise packaging materials. 
     While the invention has been described in connection with various aspects, it will be understood that the invention is capable of further modifications. This application is intended to cover any variations, uses or adaptation of the invention following, in general, the principles of the invention, and including such departures from the present disclosure as come within the known and customary practice within the art to which the invention pertains.