PATENT DOCUMENT

Publication Number: US-9537612-B2
Application Number: US-201414503106-A
Country: US
Kind Code: B2

Title: Restrictions on transmissions of control plane data with carrier aggregation

Abstract:
The disclosure describes apparatus and methods for communicating control plane data with a mobile device in a Long Term Evolution (LTE) network employing carrier aggregation. A network apparatus, such as an enhanced NodeB (eNodeB) or a mobility management entity (MME), can be configured to evaluate a measurement report (MR) received from a mobile device for one or more radio frequency (RF) conditions associated with a primary network cell and one or more RF conditions associated with a secondary network cell. Then, based on the evaluation, the network apparatus can determine to communicate the control plane data with the mobile device via the primary network cell, the secondary network cell, or both. The control plane data can correspond to non-access stratum (NAS) information, radio resource control (RRC) information, or a hybrid automatic repeat request (HARQ) retransmission of previously transmitted control plane data.

Claims:
What is claimed is: 
     
       1. A method for designating control plane signaling operations between a primary network cell and a secondary network cell of a Long Term Evolution (LTE) network, the method comprising:
 at a network apparatus in communication with a mobile device that communicates with the LTE network via both the primary network cell and the secondary network cell:
 evaluating one or more network conditions associated with downlink communication to the mobile device via the primary network cell and one or more network conditions associated with downlink communication to the mobile device via the secondary network cell; 
 determining whether to communicate control plane data to the mobile device via the primary network cell, via the secondary network cell, or via both the primary and secondary network cells based at least in part on the evaluating; and 
 sending the control plane data to the mobile device via the primary network cell, via the secondary network cell, or via both the primary and secondary network cells based at least in part on the determining. 
 
 
     
     
       2. The method of  claim 1 , wherein:
 the control plane data corresponds to non-access stratum (NAS) information or radio resource control (RRC) information; and 
 the network apparatus is an enhanced NodeB (eNodeB) base station or a mobility management entity (MME) of the LTE network. 
 
     
     
       3. The method of  claim 1 , wherein:
 the primary network cell is a primary carrier cell of the mobile device and the secondary network cell is a secondary carrier cell of the mobile device; and 
 the primary carrier cell and secondary carrier cell provide communication using carrier aggregation for the mobile device within the LTE network. 
 
     
     
       4. The method of  claim 3 , wherein the primary network cell and the secondary network cell communicate with the mobile device using inter-band non-contiguous component carriers that utilize different frequency resources within different radio frequency (RF) bands. 
     
     
       5. The method of  claim 1 , further comprising:
 receiving at least one measurement report (MR) from the mobile device, 
 wherein the at least one MR includes information corresponding to the one or more network conditions associated with downlink communication to the mobile device via the primary network cell and information corresponding to the one or more network conditions associated with downlink communication to the mobile device via the secondary network cell. 
 
     
     
       6. The method of  claim 5 , wherein the at least one MR comprises one or more of: a channel quality indicator (CQI), a pre-coding matrix indicator (PMI), or a rank indicator (RI) for the primary network cell, and one or more of: a CQI, a PMI, or a RI for the secondary network cell. 
     
     
       7. The method of  claim 1 , wherein:
 the one or more network conditions associated with downlink communication to the mobile device via the primary network cell are measured radio frequency (RF) conditions of the primary network cell that comprise at least one of: 
 a reference signal received power (RSRP), 
 a received signal strength indication (RSSI), or 
 a signal to interference plus noise ratio (SINR); and 
 the one or more network conditions associated with the downlink communication to the mobile device via secondary network cell are measured RF conditions of the secondary network cell that comprise at least one of: the RSRP, the RSSI, or the SINR. 
 
     
     
       8. The method of  claim 1 , further comprising:
 evaluating at least one of:
 a circuit-switched fallback (CSF) condition for the mobile device, or 
 block error rate (BLER) information for instantaneous downlink hybrid automatic repeat request (HARQ) at the network apparatus or for instantaneous uplink HARQ at the mobile device, 
 
 wherein the determining whether to communicate control plane data to the mobile device via the primary network cell, via the secondary network cell, or via both the primary and second network cells is further based at least in part on the evaluating the at least one of the CSF condition for the mobile device or the BLER information. 
 
     
     
       9. The method of  claim 1 , wherein the network apparatus sends the control plane data to the mobile device:
 via the primary network cell when the one or more network conditions associated with downlink communication to the mobile device via the primary network cell are better than the one or more network conditions associated with downlink communication to the mobile device via the secondary network cell; 
 via the secondary network cell when the one or more network conditions associated with downlink communication to the mobile device via the secondary network cell are better than the one or more network conditions associated with downlink communication to the mobile device via the primary network cell; and 
 via the primary network cell by default. 
 
     
     
       10. The method of  claim 1 , further comprising:
 continuing to send the control plane data to the mobile device via the primary network cell, via the secondary network cell, or via both the primary and secondary network cells during a network selected time interval or until a measurement report (MR) is received from the mobile device. 
 
     
     
       11. A network apparatus, comprising:
 one or more processors; and 
 a storage device storing executable instructions that, when executed by the one or more processors, cause the network apparatus to:
 receive a measurement report (MR) from a user equipment (UE) communicating within a Long Term Evolution (LTE) network; 
 evaluate the MR received from the UE to determine whether to communicate control plane data in the downlink direction to the UE via a primary carrier cell (PCC), via a secondary carrier cell (SCC), or via both the PCC and the SCC, the PCC and the SCC providing communication with carrier aggregation for the UE within the LTE network; and 
 send the control plane data to the UE via the PCC, via the SCC, or via both the PCC and the SCC based at least in part on evaluation of the MR received from the UE. 
 
 
     
     
       12. The network apparatus of  claim 11 , wherein the network apparatus sends duplicate copies of the control plane data to the UE via both the PCC and the SCC when the MR indicates that radio frequency (RF) conditions are poor for downlink communication to the UE within the LTE network. 
     
     
       13. The network apparatus of  claim 12 , wherein the duplicate copies of the control plane data sent to the UE via both the PCC and the SCC are hybrid automatic repeat request (HARM) retransmissions of control plane data previously sent to the UE via the PCC or via the SCC. 
     
     
       14. The network apparatus of  claim 11 , wherein the network apparatus communicates the control plane data to the UE:
 via the PCC when the MR indicates that radio frequency (RF) conditions for downlink communication to the UE via the PCC are better than RF conditions for downlink communication to the UE via the SCC; and 
 via the SCC when the MR indicates that RF conditions for downlink communication to the UE via the SCC are better than RF conditions for downlink communication to the UE via the PCC. 
 
     
     
       15. The network apparatus of  claim 14 , wherein the control plane data sent to the UE via the PCC or the SCC is a hybrid automatic repeat request (HARM) retransmission of control plane data previously sent to the UE via the PCC or the SCC. 
     
     
       16. The network apparatus of  claim 11 , wherein the PCC and the SCC communicate with the UE using inter-band non-contiguous component carriers that utilize different frequency resources within different radio frequency (RF) bands. 
     
     
       17. The network apparatus of  claim 11 , wherein the MR comprises one or more of: a channel quality indicator (CQI), a pre-coding matrix indicator (PMI), or a rank indicator (RI) for the PCC, and one or more of: a CQI, a PMI, or a RI for the SCC. 
     
     
       18. A non-transitory computer readable medium storing executable instructions that, when executed by one or more processors of a network apparatus, cause the network apparatus to:
 receive a measurement report (MR) from a user equipment (UE) communicating within a Long Term Evolution (LTE) network; 
 evaluate the MR received from the UE to determine whether to communicate control plane data in the downlink direction to the UE via a primary carrier cell (PCC), via a secondary carrier cell (SCC), or via both the PCC and the SCC, the PCC and the SCC providing communication with carrier aggregation for the UE within the LTE network; and 
 send duplicate copies of the control plane data to the UE via both the PCC and the SCC when the MR indicates that radio frequency conditions (RF) are poor for the UE within the LTE network. 
 
     
     
       19. The non-transitory computer readable medium of  claim 18 , wherein the duplicate copies of the control plane data sent to the UE via both the PCC and the SCC are hybrid automatic repeat request (HARQ) retransmissions of control plane data previously sent to the UE via the PCC or via the SCC. 
     
     
       20. The non-transitory computer readable medium of  claim 18 , wherein the PCC and the SCC communicate with the UE using inter-band non-contiguous component carriers that utilize different frequency resources within different radio frequency (RF) bands.

Description:
CROSS REFERENCE TO RELATED APPLICATION(S) 
     This application claims priority to U.S. Provisional Application No. 61/913,725, filed on Dec. 9, 2013, and entitled “RESTRICTIONS ON TRANSMISSIONS OF CONTROL PLANE DATA WITH CARRIER AGGREGATION,” which is incorporated by reference herein in its entirety for all purposes. 
    
    
     FIELD 
     The described embodiments generally relate to wireless communications, and more particularly, to procedures for effectively communicating control-plane data between a network entity and a mobile device within different carrier aggregation scenarios. 
     BACKGROUND 
     Fourth generation (4G) cellular networks employing newer radio access technology systems that implement the 3 rd  Generation Partnership Project (3GPP) Long Term Evolution (LTE) and LTE Advanced (LTE-A) standards are rapidly being developed and deployed within the United States and abroad. LTE-A brings with it the aggregation of multiple component carriers (CCs) to enable this wireless communications standard to meet the bandwidth requirements of multi-carrier systems that cumulatively achieve data rates not possible by predecessor LTE versions. 
     Within both LTE and LTE-A telecommunication networks, the mobility management entity (MME) and the enhanced NodeB (eNodeB) base station are independently responsible for implementing various control-plane signaling procedures. For example, the MME is responsible for establishing and releasing radio bearer connections for user equipment (UE), affecting UE transitions from idle mode to connected mode (and vice versa) by generating corresponding paging messages, implementing various communication security features, etc. This functionality is referred to as the Non-Access Stratum (NAS) within the LTE protocol architecture, which represents operations and communications between the evolved packet core (EPC) and the UE; the Access Stratum (AS) represents operations and communications between the eNodeB and the UE within the LTE protocol architecture. 
     The eNodeB is responsible for various radio resource control (RRC) control-plane activities, including system information broadcasting, transmitting paging messages emanating from MMEs, RRC parameter configuration for UEs, network cell selection and reselection procedures, measurement and reporting configuration for UEs, etc. In various implementations, RRC control plane signaling may be performed in conjunction with one or more of the following LTE protocol entities or layers: the packet data convergence protocol (PDCP), the radio link control (RLC) layer, the medium access control (MAC) layer, and the physical (PHY) layer. Further, both control-plane data and user-plane data can be multiplexed within the MAC layer and communicated to an intended recipient via the PHY layer, in the downlink (DL) or in the uplink (UL), during the same transmission time interval (TTI). 
     Regardless of which network device, e.g., an MME or an eNodeB in the DL, or a UE in the UL, is communicating LTE control-plane data, it is generally understood that control-plane data consists of time-sensitive information that must be communicated between or amongst various network devices in an efficient and predictable manner. Unfortunately, in modern LTE-A networks, which employ carrier aggregation to increase cumulative communications bandwidth and improve communications throughput, control-plane signaling (e.g., NAS or RRC communications) is not always designated to the most appropriate DL or UL communication resource, to ensure timely reception of sensitive control-plane data by one or more intended recipients. In fact, the present 3GPP LTE-A standard (i.e., relating to Releases 10-12) is silent with respect to identifying which network entity (e.g., a primary carrier cell or a secondary carrier cell) is designated to communicate control-plane data corresponding to one or more component carrier network cells during various DL communications. 
     As such, there exists a need for solutions that restrict control-plane data communications to pre-designated network entities or to dynamically-designated network entities as changing network conditions may require, particularly in view of various unanticipated radio link failure (RLF) scenarios. In this regard, it would be beneficial to improve the likelihood of communicating control-plane data in a timely manner within LTE-A networks employing carrier aggregation. 
     SUMMARY 
     This disclosure describes apparatus and procedures for communicating control plane data between a network apparatus and a mobile device within a Long Term Evolution (LTE) network employing carrier aggregation. In various embodiments, a network apparatus, e.g., an enhanced NodeB (eNodeB) base station or a mobility management entity (MME), can be configured to evaluate one or more network conditions associated with a primary network cell and one or more network conditions associated with a secondary network cell, determine when to communicate control plane data, e.g., corresponding to non-access stratum (NAS) information or radio resource control (RRC) information, with the mobile device via the primary network cell or the secondary network cell based at least in part on the evaluations of the network conditions. Thereafter, the network apparatus can be configured to send the control plane data to the mobile device via the primary network cell or the secondary network cell, or both. 
     In accordance with some aspects, the primary network cell may be a primary carrier cell of the mobile device and the secondary network cell may be a secondary carrier cell of the mobile device, where both the primary carrier cell (PCC) and secondary carrier cell (SCC) support carrier aggregation for the mobile device within the LTE network. 
     In various implementations, the primary network cell and the secondary network cell can be configured as inter-band non-contiguous component carriers that respectively utilize different frequency resources within different radio frequency (RF) bands for communicating with the mobile device. 
     In other aspects, the network apparatus can be configured to receive a measurement report (MR) from the mobile device, where the MR includes information corresponding to the one or more network conditions associated with the primary network cell, as well as information corresponding to the one or more network conditions associated with the secondary network cell. 
     In some scenarios, the MR may comprise one or more of a channel quality indicator (CQI), a pre-coding matrix indicator (PMI), and a rank indicator (RI) for the primary network cell, and one or more of a CQI, a PMI, and a RI for the secondary network cell. Further, the one or more network conditions associated with the primary network cell can be measured RF conditions of the primary network cell that comprise at least one of a reference signal received power (RSRP), a received signal strength indication (RSSI), and a signal to interference plus noise ratio (SINR). Similarly, the one or more network conditions associated with the secondary network cell can be measured RF conditions of the secondary network cell that comprise at least one of a RSRP, a RSSI, and a SINR. 
     In some aspects, the network apparatus can be configured to evaluate at least one of a circuit-switched fallback (CSF) condition for the mobile device and block error rate (BLER) information for instantaneous downlink hybrid automatic repeat request (HARQ) at the network apparatus or for instantaneous uplink HARQ at the mobile device, and then determine to send the control plane data to the mobile device via the primary network cell or the secondary network cell based at least in part on evaluating at least one of the CSF condition for the mobile device and/or the corresponding BLER information. 
     In other aspects, the network apparatus can be configured to determine to send the control plane data to the mobile device via the primary network cell when the one or more network conditions associated with the primary network cell are better than the one or more network conditions associated with the secondary network cell, determine to send the control plane data to the mobile device via the secondary network cell when the one or more network conditions associated with the secondary network cell are better than the one or more network conditions associated with the primary network cell, or alternatively, determine to send the control plane data to the mobile device via the primary network cell by default (e.g., when the secondary network cell is assumed to be a less desirable option for communicating control plane data with the mobile device by the network). 
     In one embodiment, the control plane data can be transmitted to the mobile device via the primary network cell or the secondary network cell during a network selected time interval; alternatively, the control plane may not be transmitted to the mobile device until a MR is received from the mobile device. 
     In various embodiments, a network apparatus can comprise one or more processors and a storage device storing executable instructions that, when executed by the one or more processors, cause the network apparatus to receive a MR from a user equipment (UE) communicating within an LTE network, evaluate the MR to determine to communicate control plane data with the UE using a PCC or a SCC, wherein the PCC and the SCC support carrier aggregation for the UE within the LTE network, and send the control plane data to the UE via the PCC or the SCC. 
     In some aspects, execution of the executable instructions can further cause the network apparatus to determine to communicate the control plane data with the UE via the PCC and the SCC when the MR indicates that RF conditions are poor for the UE within the LTE network, and send duplicate copies of the control plane data to the UE via the PCC and the SCC. In this regard, the duplicate copies of the control plane data can be HARQ retransmissions of control plane data that was previously sent to the UE via the PCC or the SCC. 
     In other aspects, execution of the executable instructions may further cause the network apparatus to determine to communicate the control plane data with the UE via the PCC when the MR indicates that RF conditions for the PCC are better than RF conditions for the SCC, or alternatively, determine to communicate the control plane data with the UE via the SCC when the MR indicates that RF conditions for the SCC are better than RF conditions for the PCC. In either scenario, the control plane data sent to the UE via the PCC or the SCC may be a HARQ retransmission of control plane data that was previously sent to the UE via the PCC or the SCC. 
     In some embodiments, a non-transitory computer readable medium can store executable instructions that, when executed by one or more processors of a network apparatus, cause the network apparatus to receive a MR from a UE communicating within an LTE network, evaluate the MR to determine to communicate control plane data with the UE using a PCC and a SCC when the MR indicates that RF conditions are poor for the UE within the LTE network, where the PCC and the SCC support carrier aggregation for the UE, and then send duplicate copies of the control plane data to the UE via the PCC and the SCC. 
     In various implementations, the duplicate copies of the control plane data can be HARQ retransmissions of control plane data that was previously sent to the UE via the PCC or the SCC. 
     This Summary is provided merely for purposes of summarizing some example embodiments so as to provide a basic understanding of some aspects of the subject matter described herein. Accordingly, it will be appreciated that the above-described features are merely examples and should not be construed to narrow the scope or spirit of the subject matter described herein in any way. Other features, aspects, and advantages of the subject matter described herein will become apparent from the following Detailed Description, Figures, and Claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The described embodiments and the advantages thereof may best be understood with reference to the following description taken in conjunction with the accompanying drawings. These drawings are not necessarily drawn to scale, and they are in no way intended to limit or exclude foreseeable modifications thereto in form and detail that may be made by one having ordinary skill in the art at the time of this disclosure. 
         FIG. 1  shows a wireless communication network including Long Term Evolution (LTE) and LTE Advanced (LTE-A) network cells supporting multiple user equipment devices (UEs), which can be configured to communicate control-plane data in the downlink (DL) or in the uplink (UL), in accordance with various embodiments of the disclosure. 
         FIG. 2  shows a wireless communication network diagram depicting an LTE-A compliant UE that is in communications with a primary carrier cell (PCC) and two secondary carrier cells (SCCs) in a carrier aggregation scenario, in accordance with various implementations of the disclosure. 
         FIGS. 3A-C  show three distinct carrier aggregation representations that depict two intra-band component carrier (CC) frequency resource diagrams and one inter-band CC frequency resource diagram, in accordance with various embodiments of the disclosure. 
         FIG. 4  shows a block diagram of the LTE protocol architecture that delineates control-plane communications from user-plane communications, in accordance with some implementations of the disclosure. 
         FIG. 5  shows a network apparatus (e.g., an eNodeB or an MME) including a network resource controller having a control-plane signaling component and a DL/UL HARQ scheduler component, in accordance with various embodiments. 
         FIG. 6  shows a block diagram of a wireless communication device including a device resource manager having a control-plane signaling component, a measurement and reporting component, and a HARQ signaling component, in accordance with some implementations of the disclosure. 
         FIG. 7A  shows a block diagram depicting a carrier aggregation scenario where a PCC is designated as a default network resource for conducting various control-plane data communications with a UE, in accordance with some embodiments. 
         FIG. 7B  shows a block diagram depicting a carrier aggregation scenario where control-plane data communications with a UE are dynamically allocated to either a PCC or to a preferred SCC based on various radio frequency condition evaluations, in accordance with various implementations of the disclosure. 
         FIG. 8  shows a flowchart depicting a procedure for dynamically designating a PCC or a SCC for conducting control-plane data communications, in accordance with some embodiments of the disclosure. 
         FIG. 9  shows a block diagram depicting DL HARQ scheduling with semi-persistent scheduling (SPS) procedures for LTE communications, in accordance with some implementations. 
         FIG. 10  shows a block diagram depicting UL HARQ scheduling procedures for LTE communications, in accordance with other embodiments of the disclosure. 
         FIG. 11  shows a block diagram depicting a selective HARQ retransmission of control-plane data between multiple network entities (e.g., a PCC and a SCC) and a UE in a carrier aggregation scenario, in accordance with various implementations. 
         FIG. 12  shows a flowchart depicting a procedure for performing selective HARQ retransmissions of control-plane data, in accordance with some embodiments of the disclosure. 
         FIG. 13  shows a block diagram depicting a dynamic HARQ retransmission of control-plane data between multiple network entities (e.g., a PCC and a SCC) and a UE, in accordance with various embodiments. 
         FIG. 14  shows a flowchart depicting a procedure for performing dynamic HARQ retransmissions of control-plane data, in accordance with some implementations of the disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Representative examples for designating one or more network entities to transmit long term evolution (LTE) control-plane data in the downlink (DL) and/or in the uplink (UL) are described within this section. Further, various examples for performing selective and dynamic LTE hybrid automatic repeat request (HARQ) retransmissions of control-plane data, are also described herein. These examples are provided to add context to, and to aid in the understanding of, the subject matter of this disclosure. It should be apparent that the present disclosure may be practiced with or without some of the specific details described herein. Further, various modifications and/or alterations can be made to the subject matter described herein, and illustrated in the corresponding figures, to achieve similar advantages and results, without departing from the spirit and scope of the disclosure. 
     References are made in this section to the accompanying drawings, which form a part of the disclosure and in which are shown, by way of illustration, various implementations corresponding to the described embodiments herein. Although the embodiments of this disclosure are described in sufficient detail to enable one having ordinary skill in the art to practice the described implementations, it should be understood that these examples are not to be construed as being overly-limiting or all-inclusive. 
     In accordance with various embodiments described herein, the terms “wireless communication device,” “wireless device,” “mobile device,” “mobile station,” and “user equipment” (UE) may be used interchangeably herein to describe one or more common consumer electronic devices that may be capable of performing procedures associated with various embodiments of the disclosure. In accordance with various implementations, any one of these consumer electronic devices may relate to: a cellular phone or a smart phone, a tablet computer, a laptop computer, a notebook computer, a personal computer, a netbook computer, a media player device, an electronic book device, a MiFi® device, a wearable computing device, as well as any other type of electronic computing device having wireless communication capability that can include communication via one or more wireless communication protocols such as used for communication on: a wireless wide area network (WWAN), a wireless metro area network (WMAN) a wireless local area network (WLAN), a wireless personal area network (WPAN), a near field communication (NFC), a cellular wireless network, a fourth generation (4G) LTE, LTE Advanced (LTE-A), and/or 5G or other present or future developed advanced cellular wireless networks. 
     The wireless communication device, in some embodiments, can also operate as part of a wireless communication system, which can include a set of client devices, which can also be referred to as stations, client wireless devices, or client wireless communication devices, interconnected to an access point (AP), e.g., as part of a WLAN, and/or to each other, e.g., as part of a WPAN and/or an “ad hoc” wireless network. In some embodiments, the client device can be any wireless communication device that is capable of communicating via a WLAN technology, e.g., in accordance with a wireless local area network communication protocol. In some embodiments, the WLAN technology can include a Wi-Fi (or more generically a WLAN) wireless communication subsystem or radio, the Wi-Fi radio can implement an Institute of Electrical and Electronics Engineers (IEEE) 802.11 technology, such as one or more of: IEEE 802.11a; IEEE 802.11b; IEEE 802.11g; IEEE 802.11-2007; IEEE 802.11n; IEEE 802.11-2012; IEEE 802.11 ac; or other present or future developed IEEE 802.11 technologies. 
     Additionally, it should be understood that the UEs described herein may be configured as multi-mode wireless communication devices that are also capable of communicating via different third generation (3G) and/or second generation (2G) RATs. In these scenarios, a multi-mode UE can be configured to prefer attachment to LTE networks offering faster data rate throughput, as compared to other 3G legacy networks offering lower data rate throughputs. For instance, in some implementations, a multi-mode UE may be configured to fall back to a 3G legacy network, e.g., an Evolved High Speed Packet Access (HSPA+) network or a Code Division Multiple Access (CDMA) 2000 Evolution-Data Only (EV-DO) network, when LTE and LTE-A networks are otherwise unavailable. 
       FIG. 1  depicts a wireless communication system  100  that is compliant with the 3GPP Evolved Universal Terrestrial Radio Access (E-UTRA) air interface, and includes, but is not limited to including, one LTE network cell  102  and two LTE-A network cells  104   a - b , respectively having enhanced NodeB (eNodeB) base stations (e.g., depicted as radio towers) that can communicate between and amongst each other via the LTE-X2 interface. Further, the E-UTRA compliant communication system  100  can include any number of mobility management entities (MMEs)  108   a - c , serving gateways (S-GWs)  108   a - c , PDN gateways (P-GWs)  110 , etc., which, as part of the evolved packet core (EPC), can communicate with any of the LTE and LTE-A cell,  102  and  104   a - b , eNodeBs via the LTE-S1 interface. Additionally, the E-UTRA communication system  100  can include any number of UEs  106  that may be provided wireless communications service by one or more of the eNodeBs of the LTE and LTE-A cells,  102  and  104   a - b , at any particular time. 
     By way of example, a UE  106  may be located within one or more LTE-A cell(s)  104   a - b  and in an LTE radio resource control (RRC) connected mode when it initiates a voice over LTE (VoLTE) application to establish a voice call. The UE  106  running the VoLTE application can place a VoLTE voice call to an intended recipient by communicating voice data to a serving eNodeB, which forwards the call through the EPC,  108   a - c  and  110 , and thereby connects to the Internet  112  to transfer the VoLTE communications through an IP Multimedia Subsystem (IMS) network between the caller UE  106  and a receiving device of the intended recipient, which may be a part of a remote network. Alternatively, the UE  106  can initiate any number of different UE-resident applications that may be respectively associated with a particular data type, e.g., streaming audio data, streaming audio-video data, website data, text data, etc., to attempt to transfer IP-based application data via its serving LTE-A network cell(s)  104   a - b  over the Internet  112 . 
     In various embodiments, any of the MMEs  108   a - c  and/or any of the eNodeB base stations of the LTE-A cells  104   a - b , which are capable of supporting carrier aggregation, can be configured to communicate control-plane data to any of the UEs  106  in the DL. Alternatively, any of the UEs  106  may be capable of communicating control-plane data via any of the LTE-A cells  104   a - b  in the UL. In this regard, it should be understood that the MMEs  108   a - b  can perform Non-Access Stratum (NAS) control-plane signaling between the EPC and the UE  106  via the eNodeB over the radio access network (RAN) portion of the network. In some scenarios, NAS signaling can include, but is not limited to including, procedures for establishing and releasing radio bearer connections for user equipment (UE), affecting UE transitions from idle mode to connected mode (and vice versa) by generating corresponding paging messages, implementing various communication security features, etc. 
     Further, the eNodeB base stations of the LTE-A cells  104   a - b  can be configured to perform various radio resource control (RRC) control-plane signaling procedures, including, but not limited to including, system information broadcasting, transmitting paging messages emanating from MMEs, RRC parameter configuration for UEs, network cell selection and reselection procedures, measurement and reporting configuration for UEs, etc. In various implementations, RRC control plane signaling may be performed in conjunction with one or more of the following LTE protocol entities or layers: the packet data convergence protocol (PDCP), the radio link control (RLC) layer, the medium access control (MAC) layer, and the physical (PHY) layer. It should be understood that control-plane data and user-plane data can be multiplexed within the MAC layer and communicated to an intended recipient via the PHY layer, in the downlink (DL) or in the uplink (UL), e.g., during the same transmission time interval (TTI). 
       FIG. 2  shows a wireless communication network diagram  200  depicting an LTE-A compliant UE  206  that is in communications with a primary carrier cell (PCC)  210  and two secondary carrier cells (SCCs),  212  and  214 , in a carrier aggregation scenario. By way of example, and with reference to 3GPP LTE-A Releases 10, 11, and 12, the LTE-A compliant UE  206  can communicate control-plane data with the eNodeB base station  202  (e.g., in the DL or the UL) that can have multiple antennas for providing radio coverage via three distinct radio frequency resources, F 1 , F 2 , and F 3 , which are individual component carriers (CCs) for communications that can be provided to UE  206  in aggregate, to increase communications bandwidth and throughput. From the perspective of the LTE-A compliant UE  206 , the CC radio frequency resource F 1  can be associated with the PCC  210 , the CC radio frequency resource F 2  can be associated with the SCC  212 , and the CC radio frequency resource F 3  can be associated with the SCC  214 . Alternative carrier aggregation representations for this frequency resource scenario will be described further herein for  FIGS. 3A-C . 
     The communication network diagram  200  also depicts two LTE compliant UEs,  204  and  208 , with reference to 3GPP LTE Releases 8 and 9, which are not capable of communicating using carrier aggregation. By way of example, the LTE compliant UE  204  can communicate control-plane data with the eNodeB base station  202  (in the DL or the UL) via a single frequency resource F 1 , and the LTE compliant UE  208  may be configured to communicate control-plane data with the eNodeB base station  202  (in the DL or the UL) via a single frequency resource F 3 . In the single carrier scenario, LTE compliant UEs,  204  and  208 , employ individual standard-designated system bandwidths that limit achievable data rate throughput to roughly 300 Mbits/sec. in the DL, and roughly 75 Mbits/sec. in the UL (real world implementations may vary). 
       FIGS. 3A-C  show three distinct carrier aggregation representations depicting two intra-band CC frequency resource diagrams,  300  and  310 , and one inter-band CC frequency resource diagram  320 , in accordance with various embodiments. As is generally understood, in 3GPP LTE and LTE-A, an individual CC is limited to communicating at various designated system bandwidths  308  ranging from 1.4 MHz up to 20 MHz. As such, the cumulative DL data rate throughput achievable in carrier aggregation scenarios can increase the single carrier data-rate throughput of roughly 300 Mbits/sec. by some multiplier value, relating to the number of CCs employed (up to 5 CCs in LTE-A). 
       FIG. 3A  shows a carrier aggregation representation depicting an intra-band contiguous CC frequency resource diagram  300 , where each aggregated CC,  302 ,  304 , and  306 , is associated with its own distinct frequency resource, F 1 , F 2 , or F 3 , within the same service provider designated DL frequency band, Band A. In the intra-band contiguous CC scenario, the three frequency resources, F 1 , F 2 , and F 3 , are sequential CC frequencies in the frequency domain. 
       FIG. 3B  shows a carrier aggregation representation depicting an intra-band non-contiguous CC frequency resource diagram  310 , where each aggregated CC,  312 ,  314 , and  316 , is associated with its own distinct frequency resource, F 1 , F 2 , or F 3 , within a single DL frequency band, Band A. However, in the intra-band non-contiguous CC scenario  310 , the three frequency resources, F 1 , F 2 , and F 3 , can be CC frequencies that are respectively separated by one or more intervening frequencies in the frequency domain, within Band A. 
       FIG. 3C  shows a more common carrier aggregation representation depicting an inter-band non-contiguous CC frequency resource diagram  320 , where each aggregated CC,  322 ,  324 , and  326 , is associated with its own distinct frequency resource, F 1 , F 2 , or F 3 , within multiple service provider designated DL frequency bands, Band A and Band B. In the inter-band non-contiguous CC scenario, the frequency resources, F 1  and F 2 , of Band A can be CC frequencies that are separated from the frequency resource F 3  of Band B in the frequency domain. For reference, 3GPP LTE-A Release 10 discusses carrier aggregation for LTE, and LTE-A Releases 11 and 12 describe various carrier aggregation enhancements including various inter-band CC band pairings. It should be understood that telecommunications service providers generally operate using both similar and dissimilar licensed LTE frequency spectrum bands. For example, within the United States, Verizon&#39;s® LTE networks operate in the 700 and 1700/2100 Mhz frequency spectra using Bands 13 and 4, whereas AT&amp;T&#39;s® LTE networks operate in the 700, 1700/2100, and 2300 MHz frequency spectra using Bands 17, 4, and 30. 
     For telecommunication networks employing LTE-A, interoperability with predecessor LTE versions requires an LTE-A CCs to employ a system bandwidth equivalent to its earlier LTE version counterparts. As such, the peak single CC LTE-A system bandwidth is capped at 20 MHz for inter-LTE RAT compatibility. However, in various carrier aggregation scenarios, an aggregate set of LTE-A CCs may be able to achieve cumulative bandwidths of up to 100 MHz (5 CCs×20 MHz, the maximum LTE standard system bandwidth) using one or more allocated LTE spectrum bands. Generally, UEs operating within LTE  102  and/or LTE-A  104   a - b  network cells employ operating bandwidths that mirror a serving cell(s) system bandwidth; this implementation ensures that sufficient radio resources are allocated to support different UE data type communications, having varying quality of service (QOS) requirements. 
       FIG. 4  shows a block diagram of the LTE protocol architecture  400  that delineates the control-plane from the user-plane amongst UE  402 , eNodeB  404 , and MME  406  entities, in accordance with various implementations of the disclosure. As previously discussed, NAS signaling  408   a - b  and RRC signaling  410   a - b  are associated with pure control-plane data communications within the LTE Protocol Architecture stack  400 , whereas PDCP layer communications  412   a - b , RLC layer communications  414   a - b , MAC layer communications  416   a - b , and PHY layer communications  418   a - b  may comprise both control-plane and user-plane communications, depending on a particular implementation. 
     As is generally understood, the PDCP layer  412   a - b  may be responsible for header de/compression of Internet Protocol (IP) data, transfer of both control-plane and user-plane data, maintenance of PDCP sequence numbers (SNs), in-sequence delivery of upper layer protocol data units (PDUs) for lower layer reestablishments, duplicate elimination of lower layer service data units (SDUs) for lower layer reestablishments of radio bearers mapped on the RLC layer  414   a - b , de/ciphering of control-plane and user-plane data, integrity protection and verification of control-plane data, etc. The RLC layer  414   a - b  may be responsible for transferring upper layer PDUs, error-correction signaling, concatenation, segmentation and reassembly of RLC SDUs, re-segmentation of RLC data PDUs, reordering of RLC data PDUs, duplicate detection, RLC SDU discarding, RLC reestablishment, error detection, etc. 
     The MAC layer  416   a - b  may be responsible for mapping between logical channels and transport channels, multiplexing of MAC SDUs from various logical channels onto transport blocks (TBs) to be delivered to the PHY layer  418   a - b  on transport channels, demultiplexing of MAC SDUs from various logical channels from TBs delivered from the PHY layer  418   a - b  on transport channels, scheduling information reporting, error-correction through HARQ signaling, priority handling between and amongst UEs via dynamic scheduling, priority handling between logical channels of a UE, logical channel prioritization, etc. The PHY layer  418   a - b  may be responsible for transferring information from various MAC layer  416   a - b  transport channels over the E-UTRA air interface, controlling adaptive modulation and coding (AMC), performing Tx power control procedures, performing cell searching during synchronization and handover procedures, communication channel measurements for the RRC layer  410   a - b , etc. 
       FIG. 5  shows a network apparatus  500  that may be representative of an eNodeB  404  or an MME  406 , in accordance with various embodiments. In one scenario, the network apparatus  500  may be a MME  406  that includes a network resource controller  512  with a control-plane signaling component  514  that is capable of performing various NAS functions (described in further detail herein), and processing circuitry  502  including one or more processors  504  and a memory component  506 . In another scenario, the network apparatus  500  may be an eNodeB  404  base station that includes a network resource controller  512  with a control-plane signaling component  514  that is capable of performing various RRC functions (described in further detail herein), a DL radio resources assignment component  516 , an UL radio resource assignment component  518 , and a DL/UL HARQ scheduler  520 , as well as, processing circuitry  502  including one or more processor(s)  504  and a memory component  506 , and an RF circuit  508  that includes an LTE modem and one or more wireless communications transceivers. 
     When the network apparatus  500  is representative of an eNodeB  404  base station, the network resource controller  512  may be configured to utilize its DL radio resource assignment component  516  to generate and/or issue various DL radio resource assignments (e.g., carrier DL RB grants) to one or more UEs located within its corresponding network cells (e.g., within LTE-A PCC cell  210  and/or SCC cells  212  and  214 ). Further, the network resource controller  512  may also be configured to utilize its UL radio resource assignment component  514  to generate and/or issue various UL radio resource assignments (e.g., carrier UL RB grants) to one or more UEs located within its corresponding network cells (e.g., within LTE-A PCC cell  210  and SCC cells  212  and  214 ). The network resource controller  512  of the network apparatus  500  may be able to employ its DL/UL HARQ scheduler component  520  to determine which UEs  106  should receive various control-plane data HARQ retransmissions, and on what RBs these HARQ retransmissions should be communicated during a respective TTI, in the DL or in the UL. 
     In various configurations, the processing circuitry  502  of the network apparatus  500  may be configured to perform various control-plane signaling activities, including control-plane data transmissions and HARQ retransmissions, e.g., by executing instructions of its control-plane signaling component  514  and its DL/UL HARQ scheduler  520 , in accordance with one or more embodiments disclosed herein. In this regard, the processing circuitry  502  can be configured to perform and/or control performance of one or more functionalities of the network apparatus  500  in accordance with various implementations, and thus can provide functionality for performing control-plane signaling operations in the DL or in the UL, along with other communication procedures of the network apparatus  500 , in accordance with various embodiments. The processing circuitry  502  may further be configured to perform data processing, application execution, and/or other control and management functions according to one or more embodiments of the disclosure. 
     The network apparatus  500 , or portions or components thereof, such as the processing circuitry  502 , can include one or more chipsets, which can respectively include any number of coupled microchips thereon. The processing circuitry  502  and/or one or more other components of the network apparatus  500  may also be configured to implement functions associated with various selective HARQ retransmissions of control-plane data and dynamic HARQ retransmissions of control-plane data using multiple chipsets. In some scenarios, the network apparatus  500  may be associated with, or employed as, a MME  108   a - c  or an eNodeB base station of one or more LTE-A cells  104   a - b , to operate within the wireless communication system  100  of  FIG. 1 , or alternatively within the wireless communication network  200  of  FIG. 2 . In this implementation, the network apparatus  500  may include one or more chipsets configured to enable the network apparatus  500  to operate within an LTE network employing carrier aggregation, as a network entity, or as joint network entities, capable of providing LTE-A communications service to any number of UEs  106  located within its corresponding wireless coverage area(s) (e.g., coverage areas associated with a PCC  210  and one or more SCCs,  212  and  214 , of  FIG. 2 ). 
     In some scenarios, the processing circuitry  502  of the network apparatus  500  may include one or more processor(s)  504  and a memory component  506 . The processing circuitry  502  may be in communication with, or otherwise coupled to, a radio frequency (RF) circuit  508  having an LTE-A compliant modem and one or more wireless communication transceivers  510 . In various implementations, the RF circuit  508  including the LTE-A compliant modem and transceiver(s)  510  may be configured to communicate using different LTE RAT types. 
     In various implementations, the processor(s)  504  may be configured and/or employed in a variety of different forms. For example, the processor(s)  504  may be associated with any number of microprocessors, co-processors, controllers, or various other computing or processing implements, including integrated circuits such as, for example, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or any combination thereof. In various scenarios, multiple processors  504  can be coupled to and/or configured in operative communication with each other and these components may be collectively configured to perform one or more procedures of the network apparatus  500  as described herein in the form of an eNodeB base station having RRC control functionality and/or in the form of a MME having NAS signaling functionality. 
     In some scenarios, the processor(s)  504  of the processing circuitry  502  can be configured to execute instructions that may be stored in the memory  506  or that can be otherwise accessible to the processor(s)  504  within some other device memory type. As such, whether configured as, or in conjunction with, hardware or a combination of hardware and software, the processor(s)  504  of the processing circuitry  502  may be capable of performing operations according to various implementations described herein, when configured accordingly. 
     In various embodiments, the memory  506  of the processing circuitry  502  may include multiple memory devices that can be associated with any common volatile or non-volatile memory type. In some scenarios, the memory  506  may be associated with a non-transitory computer-readable storage medium that can store various computer program instructions, which may be executed by the processor(s)  504  during normal program executions. In this regard, the memory  506  can be configured to store information, data, applications, instructions, or the like, for enabling the network apparatus  500  to carry out various control-plane data signaling and HARQ retransmission functions, in accordance with one or more embodiments of the disclosure. In some implementations, the memory  506  may be actively in communication with and/or coupled to the processor(s)  504  of the processing circuitry  502 , as well as one or more system buses for passing information between and amongst the different device components of the network apparatus  500 . 
     It should be appreciated that not all of the components, device elements, and hardware illustrated in and described with respect to the network apparatus  500  of  FIG. 5  may be essential to this disclosure, and thus, some of these items may be omitted, consolidated, or otherwise modified within reason. Additionally, in some implementations, the subject matter associated with the network apparatus  500  can be configured to include additional or substitute components, device elements, or hardware, beyond those that are shown within the illustrations of  FIG. 5 . 
       FIG. 6  shows a block diagram of a wireless communication device  600  (e.g., an LTE-A compliant UE) including a device resource manager  612  having a control-plane signaling component  614 , a measurement and reporting component  616 , and a HARQ signaling component  618 , as well as, processing circuitry  602  having one or more processor(s)  604  and a memory  606 , and an RF circuit  608  having an LTE modem  610  and one or more transceiver(s). In various configurations, the wireless communication device  600  can employ its control-plane signaling component  614  of its device resource manager  612  to perform both NAS and RRC signaling operations while in communication with an MME and/or and eNodeB base station. 
     Further, the wireless communication device  600  may employ its measurement and reporting component  616  of its device resource manager  612  to measure various radio frequency (RF) conditions, e.g., a reference signal received power (RSRP), a received signal strength indication (RSSI), a signal to interference plus noise ratio (SINR), etc., associated with any number of serving cells (e.g., for any of the PCC  210  and SCC,  212  and  214 , cells of  FIG. 2 ), at any particular time, and then transmit these measured RF conditions within a corresponding measurement report (MR), e.g., as one or more of a channel quality indicator (CQI), a pre-coding matrix indicator (PMI), a rank indicator (RI), etc., within one or more periodic or aperiodic (network trigger-initiated) MR(s). Additionally, the wireless communication device  600  may employ its HARQ signaling component  618  of its device resource manager  612  to perform various HARQ signaling functions (e.g., ACK/NACK messaging, UL re/transmissions, etc.), in accordance with various embodiments that are described further herein. 
     The processing circuitry  602  can be configured to perform and/or control performance of one or more functionalities of the wireless communication device  600  in accordance with various implementations, and thus, the processing circuitry  602  can provide functionality for performing various control-plane signaling activities, including control-plane data transmissions (e.g., NAS or RRC signaling) and HARQ retransmissions of control-plane data, e.g., by executing instructions of its control-plane signaling component  614  and its HARQ signaling component  618 , in accordance with one or more embodiments. In this regard, the processing circuitry  602  can be configured to perform and/or control performance of one or more functionalities of the wireless communication device  600  in accordance with various implementations, and thus can provide functionality for performing control-plane communications in the DL or in the UL, along with other communication procedures, in accordance with various embodiments. The processing circuitry  602  may further be configured to perform data processing, application execution, and/or other device functions according to one or more embodiments of the disclosure. 
     The wireless communication device  600 , or portions or components thereof, such as the processing circuitry  602 , can include one or more chipsets, which can respectively include any number of coupled microchips thereon. The processing circuitry  602  and/or one or more other components of the wireless communication device  600  may also be configured to implement functions associated with various control-plane signaling procedures of the disclosure using multiple chipsets. In some scenarios, the wireless communication device  600  may be associated with, or employed as, an LTE-A compliant UE  106  having multiple transceivers. 
     In various scenarios, the processing circuitry  602  of the wireless communication device  600  may include one or more processor(s)  604  and a memory component  606 . The processing circuitry  602  may be in communication with, or otherwise coupled to, its radio RF circuit  608  having an LTE compliant modem and one or more wireless communication transceivers  610 . In some implementations, the RF circuit  608  including the modem and the one or more transceivers  610  may be configured to communicate using different RAT types. For instance, in some embodiments the RF circuit  608  may be configured to communicate using various RATs, including one or more LTE-A RATs. 
     In some embodiments, the processor(s)  604  may be configured in a variety of different forms. For example, the processor(s)  604  may be associated with any number of microprocessors, co-processors, controllers, or various other computing or processing implements, including integrated circuits such as, for example, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or any combination thereof. In various scenarios, multiple processors  604  of the wireless communication device  600  can be coupled to and/or configured in operative communication with each other, and these components may be collectively configured to perform one or more control-plane signaling and/or HARQ retransmission procedures as described further herein. 
     In some implementations, the processor(s)  604  can be configured to execute instructions that may be stored in the memory  606 , or that can otherwise be accessible to the processor(s)  604  in some other device memory. As such, whether configured as, or in conjunction with, hardware or a combination of hardware and software, the processor(s)  604  of the processing circuitry  602  may be capable of performing operations according to various implementations described herein, when configured accordingly. 
     In various embodiments, the memory  606  of the processing circuitry  602  may include multiple memory devices that can be associated with any common volatile or non-volatile memory type. In some scenarios, the memory  606  may be associated with a non-transitory computer-readable storage medium that can store various computer program instructions which may be executed by the processor(s)  604  during normal program executions. In this regard, the memory  606  can be configured to store information, data, applications, instructions, or the like, for enabling the wireless communication device  600  to carry out various functions in accordance with one or more embodiments of the disclosure. In some implementations, the memory  606  may be in communication with, and/or otherwise coupled to, the processor(s)  604  of the processing circuitry  602 , as well as one or more system buses for passing information between and amongst the different device components of the wireless communication device  600 . 
     It should be appreciated that not all of the components, device elements, and hardware illustrated in and described with respect to the wireless communication device  600  of  FIG. 6  may be essential to this disclosure, and thus, some of these items may be omitted, consolidated, or otherwise modified within reason. Additionally, in some implementations, the subject matter associated with the wireless communication device  600  can be configured to include additional or substitute components, device elements, or hardware, beyond those depicted within the illustrations of  FIG. 6 . 
       FIG. 7A  shows a block diagram depicting a carrier aggregation scenario  700  where a PCC  702  can be designated as a default network entity/resource for communicating control-plane data (e.g., for NAS and RCC signaling) with a UE  706 , in accordance with some embodiments of the disclosure. In various implementations, the UE  706  may be an LTE-A compliant mobile device (e.g., representative of the wireless communication device  600  of  FIG. 6 ) that can communicate with one or more eNodeB base station(s), via the LTE-Uu interface, that may provide the UE  706  with wireless communications service via a PCC  702  and a SCC  704 , by employing LTE-A carrier aggregation RATs. 
     In an embodiment, all Level 1 (L1) PHY layer control data transmissions  710  may be designated for the PCC  702  by default, and the PCC  702  may additionally communicate other IP packet data with the UE  706  in the DL or in the UL via the LTE-Uu interface. However, the SCC  704  may only communicate IP packet data  712 , without L1 control data, with the UE  706  in the DL or in the UL, via the LTE-Uu Interface. The SCC  704  can coordinate its packet data transmissions (including control-plane data communications) with the PCC  702  via an inter-cell coordination link  714 , via the LTE-X2 interface, to maximize communications throughput. 
     However, in certain situations, when time-sensitive control-plane data (e.g., NAS and RRC signaling) is communicated within packet data transmissions from the PCC  702  to the UE  706 , and from the SCC  704  to the UE  706 , independently, negative outcomes may result. By way of example, when communications between the SCC  704  and the UE  706  are deemed by the network to be volatile, such as when RF conditions are poor and communications degrade to the point where a RLF could result on the communication link  712  between the SCC  704  and the UE  706 , it may be disadvantageous for the network to designate any control-plane data communications for the SCC  704 . In this scenario, it is assumed that the PCC  702  will typically have a stronger communication link  710  with the UE  706 , as compared to a communication link  712  between the SCC  704  and the UE  706 . 
     Accordingly, it may be particularly beneficial for the network to pre-designate all control-plane data communications for the PCC  702 , as opposed to the SCC  704 , such that these time-sensitive control-plane communications are only scheduled to occur via a more reliable communications link  708  between the PCC  702  and the UE  706 . In various embodiments, this designation may be implemented by the network in an effort to prevent time-sensitive control-plane data from being lost in predicable scenarios where a communication link between the SCC  704  and the UE  706  may fail. This will improve the likelihood of the UE  706  timely receiving sensitive control-plane data from the network via the most reliable communication link  708  available, between PCC  702  and the UE  706 . 
       FIG. 7B  shows a block diagram, similar to that of  FIG. 7 a   , depicting another carrier aggregation scenario  720  where control-plane data (e.g., NAS and RCC information) communications for a UE  706  can be dynamically allocated to either the PCC  702  or to a preferred SCC  704 , based on various RF condition evaluations (e.g., RF conditions that can be received by the PCC  702  within one or more periodic or aperiodic MRs) performed by a network entity (e.g., at an MME and/or an eNodeB base station), in accordance with some embodiments of the disclosure. In various scenarios, the UE  706  may be an LTE-A compliant communication device (e.g., representative of the wireless communication device  600  of  FIG. 6 ) that can communicate with one or more eNodeB base station(s), via the LTE-Uu interface, that may provide the UE  706  with wireless communications service via a PCC  702  and a SCC  704 , by employing LTE-A carrier aggregation RATs. 
     In some embodiments, various network conditions associated with both a communications link between the PCC  702  and the UE  706 , and a communications link between the SCC  704  and the UE  706 , may be evaluated by a network entity associated with at least the PCC  702  (e.g., an MME and/or an eNodeB base station) to determine which of the two carrier cells, the PCC  702  or the SCC  704 , should be designated for control-plane data communications. 
     For example, in some implementations, the PCC  702  (or a network entity associated therewith) may receive either periodic or aperiodic (network trigger-initiated) MRs  722  that can include CQI, PMI, and/or RI information relating to both RF conditions for the communications link between the PCC  702  and the UE  706 , and RF conditions for the communications link between the SCC  704  and the UE  706 . In other embodiments, the PCC  702  (or a network entity associated therewith) may already be aware of the RF conditions for these respective communications links based on historical RF condition information stored by the network, e.g., at a network entity, such as an MME or an eNodeB base station. 
     In some embodiments, a network entity associated with the PCC  702  (e.g., an eNodeB base station) may evaluate respective RF conditions  724  (received in MRs or maintained within a network entity) associated with the PCC  702  and the SCC  704 . In various scenarios, this may be accomplished by comparing one or more common RF metrics of the LTE-A communication standard, to determine whether to dynamically designate the PCC  702  or a SCC  704  as the preferred carrier cell “option” for performing all subsequent control-plane signaling operations and communications with the UE  706  after a particular time, or during a network-selected time interval. 
     In one implementation, a network entity associated with the PCC  702  can select a first option  726   a , based on comparing various RF conditions associated with one or more RF condition evaluations  724 , by instructing the PCC  702  to handle all control-plane signaling operations via a radio link  728   a  between the PCC  702  and the UE  706 . This may occur when the radio link  728   a  between the PCC  702  and the UE  706  is determined to be better than a radio link  728   b  between the SCC  704  and the UE  706 . Alternatively, in another implementation, a network entity associated with the PCC  702  or the SCC  704  can select a second option  726   b , based on comparing various RF conditions associated with one or more radio link evaluations  724 , by instructing the SCC  704  to handle all control-plane signaling operations via a radio link  728   b  between the SCC  704  and the UE  706 . This may occur when the radio link  728   b  between the SCC  704  and the UE  706  is determined to be better than a radio link  728   a  between the PCC  702  and the UE  706 . It should be understood that in various configurations, these control-plane signaling allocations for the PCC  702  or the SCC  704 , may be dynamically assigned for pre-determined periods of time or for indefinite periods of time that may be changed in real-time with the advent of various network condition triggers (e.g., in response to one or more MR trigger events). 
       FIG. 8  shows a flowchart depicting a procedure  800  for dynamically designating a PCC  702  or a SCC  704  for conducting control-plane data communications with a UE  706 , in accordance with some embodiments of the disclosure. In this regard, it should be understood that any or all of the procedures  800  depicted in  FIG. 8  may be associated with a method, or methods, that can be implemented by the execution of computer program instructions stored in a non-transitory computer-readable memory  506  of the network apparatus  500 , and optionally, in conjunction with the execution of computer program instructions stored in a non-transitory computer-readable memory  606  of a wireless communication device  600 . 
     Initially, at operation block  802 , a network apparatus  500  (e.g., an MME and/or an eNodeB base station) associated with a PCC  702  and/or a SCC  704 , may receive one or more periodic or aperiodic (network event-triggered) MRs from a particular wireless communication device  600  (e.g., the UE  706  of  FIGS. 7 a - b   ). Then, at operation block  804 , the network apparatus  500  and/or the wireless communication device  600  (or another network entity associated therewith) may compare various RF channel metrics (e.g., RSRP, RSRQ, SINR, etc.) associated with both a communication link between a PCC  702  and the UE  706 , and a communication link between a SCC  704  and the UE  706 , to determine which of the two cells provides the most reliable RF conditions for subsequent control-plane data communications with the UE  706 . 
     In certain scenarios, the network can utilize information from one or more MRs, if and when they become available, e.g., when they are transferred to the network apparatus  500  from the wireless commutation device  600  via the measurement and reporting component  616 , to make its determination of a preferred cell for handling control-plane signaling communications. Alternatively, circuit-switched fallback (CSF) conditions (at the network apparatus  500 ), block error rate (BLER) information for instantaneous UL HARQ (at the UE  600 ) or for DL HARQ (at the network apparatus  500 ) may also be evaluated to determine which of the two cells provides the most reliable and predictable RF conditions for subsequent control-plane data communications with the UE  706 . At decision block  806 , a determination is made as to whether the PCC  702  or the SCC  704  is the preferred carrier cell for subsequent control-plane data communications with the UE  706 . 
     In a scenario where the PCC  702  is determined to be the preferred carrier cell for control-plane data communications, at operation block  810 , the PCC  702  can be designated by the network (e.g., at an MME and/or an eNodeB base station) for handling future control-plane data signaling operations and communications (e.g., for NAS and RRC messaging). Alternatively, in a scenario where the SCC  704  is determined to be the preferred carrier cell for control-plane data communications, at operation block  818 , the SCC  704  may be designated by the network (e.g., at an MME and/or an eNodeB base station) for handling future control-plane data signaling operations and communications (e.g., for NAS and RRC messaging). 
       FIG. 9  shows a block diagram depicting DL HARQ scheduling with semi-persistent scheduling (SPS) procedures  900  for LTE communications, in accordance with some implementations. In general, LTE HARQ processes can attempt to retransmit failed TB communications that may include control-plane data in the DL and/or in the UL. The DL HARQ scheduling procedures  900  depict signaling interactions between the physical downlink shared channel (PDSCH)  902 , the physical downlink control channel (PDCCH)  904 , and the physical uplink control channel (PUCCH)  906 , during various DL HARQ processes. 
     As would be understood by those skilled in the art, the PDCCH  904  may include downlink control information (DCI), e.g., emanating from an eNodeB, that informs a UE  600  of various DL resource allocations for the PDSCH  902 , HARQ information relating to the PDSCH  902 , various UL scheduling grants for the physical uplink shared channel (PUSCH)  1002 , etc. The PUCCH  906  can carry DL HARQ acknowledgements (e.g., ACK/NACKs) that are transmitted by a UE  600  to a network apparatus  500  in response to the UE  600  receiving, or not receiving, various DL data transmissions via the PDSCH  902 . 
     In some situations, a DL allocation  908  may be transmitted from a network apparatus  500  having DL HARQ scheduler  520  (e.g., an eNodeB having RRC functionality) within the PDCCH  904  to a UE  600  to identify a particular set of designated DL resource blocks (RBs) where the UE  600  should attempt to decode the PDSCH  902  for DL information that may include control-plane data. Upon acquiring, or attempting to acquire, the identified DL information that may include control-plane data from the PDSCH  902  corresponding to the DL allocation  908 , an intended recipient UE  600  can send a positive DL HARQ acknowledgement (ACK) message  910  or a negative DL HARQ acknowledgement (NACK) message  914  to the network apparatus  500  via the PUCCH  906 . 
     The DL HARQ ACK/NACK acknowledgements can indicate to the network apparatus  500  (e.g., an eNodeB having RRC functionality) whether or not the DL information was received or acquired by the UE  600  and/or whether DL information that was acquired by the UE  600  is free from errors, e.g., according to a cyclic redundancy check (CRC) result. In some scenarios, a DL CRC success result  926  can indicate that DL information was acquired by a UE  600  with or without error. Alternatively, a DL CRC failure result  928  may indicate that scheduled, expected DL information was not acquired by a UE  600 . As would be understood by those skilled in the art, a UE  600  will typically issue a DL HARQ ACK message to a network apparatus  500  (e.g., an eNodeB) via the PUCCH  906  in response to receiving a DL CRC success result  926 . Likewise, a UE  600  will typically issue a DL HARQ NACK message to a network apparatus  500  (e.g., an eNodeB) in response to receiving a DL CRC failure result  928 . 
     In accordance with the DL HARQ SPS example  900 , an ongoing SPS DL resource allocation  912  may be sent by a network apparatus  500  employing the DL HARQ scheduler  520  (e.g., an eNodeB having RRC functionality) to a UE  600  to instruct the UE  600  to attempt to decode the PDSCH  902  for known, recurring DL information on a periodic basis (e.g., every 10 TTIs), such that the UE  600  is not required to further decode the PDCCH  904  until a change to the ongoing SPS allocation  912  is detected. Accordingly, at every designated SPS interval (e.g., every 10 ms.) a UE  600  can attempt to decode the PDSCH  902  for prescheduled DL information. Depending on whether or not the DL information has been successfully acquired by the UE  600  via the PDSCH  902  and/or whether or not the DL information was acquired without errors, the UE  600  can send a DL HARQ ACK message  910 ,  920 ,  922 , and  924 , or a DL HARQ NACK message  914  to the network apparatus  500  (e.g., an eNodeB) via the PUCCH  906 . 
     In various implementations, upon receiving a DL HARQ NACK  914  message via the PUCCH  906  that indicates a DL transmission failure or error (e.g., corresponding to a CRC failure result  928 ), a network apparatus  500  employing the DL HARQ scheduler  520  (e.g., an eNodeB having RRC functionality) can attempt to retransmit the DL information and/or a portion of the DL information  916  that may include control-plane data to the UE  600  at a later time, in accordance with a designated retransmission interval/duration (e.g., 4 TTIs later=4 ms.). In various scenarios, a total retransmission time or round trip time (RTT) for the UE  600  to receive the correct and/or complete DL information may be scheduled to occur within a particular number of TTIs to account for anticipated network communication and device processing delays (e.g., a DL RTT of 8 TTIs=8 ms.). 
     In some scenarios, a network apparatus  500  employing the DL HARQ scheduler  520  can evaluate a DL HARQ NACK  914  received via the PUCCH  906  to determine when to schedule a DL retransmission  916  based on various network considerations, including an application data type being communicated in the DL. The UE  600  can thereafter be informed of the DL retransmission schedule  916  by receiving a supplemental DL allocation  918  for the retransmission within the PDCCH  904 , as designated by the network apparatus  500  (e.g., an eNodeB having RRC functionality). As would be understood by those skilled in the art, this DL HARQ retransmission can occur on top of ongoing SPS operations, such that the DL HARQ procedures  900  requiring the UE  600  to decode the PDCCH  904  for retransmit control information will supersede SPS PDCCH “do not decode” durations. 
       FIG. 10  shows a block diagram depicting UL HARQ scheduling procedures  1000  for LTE communications, in accordance with other embodiments of the disclosure. Although not depicted in  FIG. 10 , it should be understood that in some implementations UL HARQ processes  1000  can occur in conjunction with SPS and/or C-DRX power saving routines. The UL HARQ scheduling procedures  1000  depict signaling interactions between the PUSCH  1002 , the PDCCH  1004 , and the physical hybrid-ARQ indicator channel (PHICH)  1006 , during various UL HARQ processes. As would be understood by those skilled in the art, the PHICH  1006  is configured to carry UL HARQ acknowledgements (e.g., ACK/NACKs) that can be transmitted by a network apparatus  500  (e.g., an eNodeB) in response to receiving, or not receiving, various expected UL data transmissions from a UE  600  that it provides LTE communications services to. 
     In some embodiments, an UL grant  1008  may be transmitted from a network apparatus  500  employing an UL HARQ scheduler  520  (e.g., an eNodeB having RRC functionality) within the PDCCH  1004  to a UE  600  to identify a particular set of designated UL RBs where the UE  600  should attempt to transmit UL information to the network apparatus  500  in accordance with a predefined TTI interval (e.g., every 4 TTIs=4 ms.). In this configuration, there will be a TTI delay between a time when the UE  600  receives the UL grant  1008  via the PDCCH  1004  and a time when the UL RBs allocated to UE  600  for the UL transmission become available. The TTI delay is intended to give the UE  600  sufficient time to process the UL data and determine how best to transmit a corresponding UL TB, e.g., in accordance with various network-designated quality of service (QoS) requirements. 
     Upon receiving, or attempting to receive, an UL transmission that may include control-plane data via the PUSCH  1002 , corresponding to an UL grant,  1008  or  1012 , a recipient network apparatus  500  (e.g., an eNodeB) can transmit either a positive UL HARQ acknowledgement (ACK) message  1010  or a negative UL HARQ acknowledgement (NACK) message  1014  to the sending UE  600  via the PHICH  1006 , e.g., on the DL from the network apparatus  500 . The UL HARQ ACK/NACK acknowledgements,  1010  and  1014 , can indicate to the UE  600  whether or not an UL TB was received or acquired by the network apparatus  500  and/or whether information of the UL TB that was acquired by the network apparatus  500  is free from errors, e.g., according to a corresponding cyclic redundancy check (CRC) result,  1020  or  1022 . In various embodiments, an UL CRC success result  1020  can indicate that the UL TB was received by the network apparatus  500  without error. Alternatively, an UL CRC failure result  1022  may indicate that the UL TB was erroneously received by the network apparatus  500 . 
     As would be understood by those skilled in the art, a network apparatus  500  (e.g., an eNodeB having RRC functionality) will typically issue an UL HARQ ACK message to a corresponding UE  600  via the PHICH  1006  in response to an UL CRC success result  1020 . Similarly, a network apparatus  500  (e.g., an eNodeB having RRC functionality) will typically issue an UL HARQ NACK message to a UE  600  via the PHICH  1006  in response to an UL CRC failure result  1022 . 
     In some implementations, upon receiving an UL HARQ NACK  1014  via the PHICH  1006  from a network apparatus  500  that indicates an UL transmission failure or error (e.g., corresponding to an UL CRC failure result  1022 ), a UE  600  can attempt to retransmit the UL TB and/or a portion of the UL TB information  1016  that may include control-plane data to the network apparatus  500  at a later time, in accordance with a designated retransmission interval (e.g., within 4 TTIs=4 ms.). In various scenarios, a total retransmission time or round trip time (RTT) for the network apparatus  500  to receive the correct and/or complete UL TB from the UE  600  may be scheduled to occur within a designated number of TTIs associated with an UL HARQ RTT to account for anticipated network communication and device processing delays (e.g., an UL RTT of 8 TTIs=8 ms.). 
       FIG. 11  shows a block diagram depicting a selective retransmission  1100  of control-plane data (e.g., NAS or RRC signaling data), emanating from a network RLC layer, between multiple network entities (e.g., a PCC  1102  and a SCC  1104 ) and a UE  1106  in a carrier aggregation scenario. It should be understood that, in various embodiments, a retransmission  1100  may occur in either the DL, between the PCC  1102 , the SCC  1104 , and the UE  1106 , or in the UL between the UE  1106  and the PCC  1102  or the SCC  1104 . In accordance with some scenarios, the PCC  1102  may transmit Tx Data A  1108  to the UE  1106  via a first communication link, and the Tx Data A can include a first transmission of control-plane data (e.g., NAS or RRC information) to the UE in the DL from the RLC layer of the network. 
     In one scenario, the RLC layer associated with the UE  1106  may determine that the Tx Data A, with the initial control-plane data, was received in error. In response to this determination, the RLC layer of the UE  1106  can transmit a HARQ NACK message to the PCC&#39;s  1102  corresponding HARQ entity, which can then forward the NACK message to the RLC layer of network. In various implementations, the NACK message may include bitmap information that identifies the network resource allocation associated with Tx Data A. 
     The RLC layer of the network may use this NACK bitmap information to coordinate with the PCC&#39;s  1102  HARQ entity and/or the SCC&#39;s  1104  HARQ entity to schedule independent, duplicate retransmissions of control-plane Data A (ReTx Data A 1  and ReTx Data A 2 ) from both the PCC  1102  and the SCC  1104  to the UE  1106 , e.g., via separate communication links  1114   a - b , to ensure that the first control-plane data transmission is received by the UE  1106  in a timely and efficient manner via a corresponding RLC layer retransmission. Alternatively, in other embodiments, the network can identify a situation where an expected ACK corresponding to Tx Data A is not received from the UE  1106 . In this scenario the RLC layer of the network can similarly coordinate with the PCC  1102  and the SCC  1104  to schedule independent, duplicate retransmissions of the first control-plane data. 
       FIG. 12  shows a flowchart depicting a procedure  1200  for performing selective retransmissions of control-plane data (e.g., NAS and RRC control information) emanating from the RLC layer of a network, in accordance with some embodiments of the disclosure. In this regard, it should be understood that any or all of the procedures  1200  depicted in  FIG. 12  may be associated with a method, or methods, that can be implemented by the execution of computer program instructions stored in a non-transitory computer-readable memory  506  of the network apparatus  500 , and optionally, in conjunction with the execution of computer program instructions stored in a non-transitory computer-readable memory  606  of a wireless communication device  600 . 
     Initially, at operation block  1202 , a NACK for an initial control-plane data transmission may be received by a network apparatus  500  (e.g., an MME or an eNodeB base station) associated with a PCC  1102  or an SCC  1104 . Alternatively, the network apparatus  500  may be able to identify a situation where an expected ACK corresponding to the initial control-plane data transmission is not received from the UE  1106 . At decision block  1204 , the network apparatus  500  may employ it RLC layer functions to determine whether a NACK response is received for the initial control-plane data transmission or whether a missing ACK scenario has occurred for the initial control-plane data transmission. 
     In a scenario where the network apparatus  500  receives an ACK response message for the initial control-plane data transmission  1210 , the procedure  1200  ends as no retransmission is required. However, in a scenario where the network apparatus  500  receives a NACK response message for the initial control-plane data transmission, or alternatively, identifies a missing ACK scenario for the initial control-plane data transmission, the process proceeds to operation block  1206 , where a duplicate HARQ retransmission for the initial control-plane data transmission is scheduled for the PCC  1102  and for one or more SCCs  1104 . Next at operation block  1208 , the initial control-plane data can be retransmitted to the UE  1106  from both the PCC  1102  and the one or more SCCs  1104 , to ensure that the initial control-plane data is received by the UE  1106  in a timely manner. 
       FIG. 13  shows a block diagram depicting a dynamic HARQ retransmission  1300  of control-plane data (e.g., NAS and RRC control information) between multiple network entities (e.g., a PCC  1302  and a SCC  1304 ) and a UE  1306  in a carrier aggregation scenario, in accordance with various implementations. It should be understood that HARQ retransmission  1300  may occur in either the DL, between the HARQ entities of the PCC  1302  and the SCC  1304  and the respective HARQ entities of the UE  1306  (e.g., according to the DL HARQ retransmission  900  discussed above for  FIG. 9 ), or in the UL between the first and second HARQ entities of the UE  1306  and the respective HARQ entities of the PCC  1302  and the SCC  1304  (e.g., according to the UL HARQ retransmission  1000  discussed above for  FIG. 10 ). 
     In accordance with various embodiments, the UE  1306  may be configured to employ its measurement and reporting component  616  to transmit periodic or aperiodic (network event-triggered) MRs  1310  to a network entity  1312  (e.g., an MME and/or an eNodeB base station) associated with the PCC  1302  and/or the SCC  1304 . Utilizing this information, the network entity  1312  may be able to determine when RF signaling conditions are poor for the UE  1306 . When RF conditions experienced by the UE  1306  are determined to be poor, the network entity  1312  may coordinate with the PPC  1302  and the SCC  1304  HARQ entities to schedule (by default) duplicate retransmissions  1314   a - b  for all control-plane data communications transmitted to the UE  1306  while the RF signaling conditions remain poor. 
     In this scenario, the PCC  1302  may transmit an initial Tx Data A (including control-plane data) to the UE  1306  over a first communication link  1308 . The network may then employ the PCC&#39;s  1302  HARQ entity to retransmit a first copy of the ReTx Data A 1  to the UE&#39;s  1306  first HARQ entity via a first communication link  1316   a ; the network may similarly employ the SCC&#39;s  1304  HARQ entity to retransmit a second copy of the ReTx Data A 2  to the UE&#39;s  1306  first HARQ entity via a second communication link  1316   b . Upon receiving the first and second copies of the ReTx Data A 1  and A 2  by the UE&#39;s  1306  respective first and second HARQ entities, the ReTx Data A 1  and A 2  can be passed through the MAC layer  1318  to the RLC layer  1320 , which will utilize only one copy of the ReTx Data A 1  or A 2  for subsequent processing  1324 . The remainder of ReTx Data A 1  or A 2  that is not utilized can be discarded  1322  at the RLC layer  1320  of the UE  1306 . 
       FIG. 14  shows a flowchart depicting a procedure  1400  for performing dynamic HARQ retransmissions of control-plane data (e.g., NAS or RRC control information), in accordance with some implementations of the disclosure. In this regard, it should be understood that any or all of the procedures  1400  depicted in  FIG. 14  may be associated with a method, or methods, that can be implemented by the execution of computer program instructions stored in a non-transitory computer-readable memory  506  of the network apparatus  500 , and optionally, in conjunction with the execution of computer program instructions stored in a non-transitory computer-readable memory  606  of a wireless communication device  600 . 
     Initially, at operation block  1402 , a network apparatus  500  (e.g., an MME or an eNodeB base station) associated with a PCC  1302  or an SCC  1304  may receive MR information corresponding the RF conditions experienced by the UE  1306  for communications with the PCC  1302  and the SCC  1304 . Next, at operation block  1404 , the network apparatus  500  can evaluate the MRs to determine whether network signaling conditions are poor, e.g., from the perspective of the UE  1306  for the PCC  1302  and/or the SCC  1304 . At decision block  1406 , a determination can be made as to whether network signaling conditions are poor for the UE  1306 . In a scenario where network signaling conditions are determined not to be poor, at operation block  1412 , the network apparatus  500  can schedule a single HARQ retransmission for control-plane data, e.g., when a corresponding NACK is received by the network. Then, at operation block  1414  the single HARQ retransmission for the control-plane data may be communicated to the UE  1306  from either the PCC  1302  or the SCC  1304 . 
     Alternatively, in a scenario where network signaling conditions are determined to be poor, at operation block  1408 , the network apparatus  500  can schedule a duplicate transmission, i.e., the same RLC protocol data unit (PDU), containing control-plane data for both the PCC  1302  and the SCC  1304 . Then, at operation block  1410 , the PCC  1302  and the SCC  1304  can retransmit respective, duplicate copies of the control plane data to the UE  1306 , to ensure that the time-sensitive control-plane data is received by the UE  1306  in a timely manner. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Further, some aspects of the described embodiments may be implemented by software, hardware, or a combination of hardware and software. The described embodiments can also be embodied as computer program code stored on a non-transitory computer-readable medium. The computer readable-medium may be associated with any data storage device that can store data which can thereafter be read by a computer or a computer system. Examples of the computer-readable medium include read-only memory, random-access memory, CD-ROMs, Solid-State Disks (SSD or Flash), HDDs, DVDs, magnetic tape, and optical data storage devices. The computer-readable medium can also be distributed over network-coupled computer systems so that the computer program code may be executed in a distributed fashion. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that some of the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of specific embodiments are presented herein for purposes of illustration and description. These descriptions are not intended to be exhaustive, all-inclusive, or to limit the described embodiments to the precise forms or details disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings, without departing from the spirit and the scope of the disclosure.

Metadata:
Filing Date: 20140930
Publication Date: 20170103
Grant Date: 20170103
Priority Date: 20131209
Inventors: KODALI SREE RAM
MAKHARIA SHIVESH
Assignee: APPLE INC
CPC Classifications: [{"code": "H04W72/23", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W72/23", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04W72/042", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/0041", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/001", "inventive": false, "first": false, "tree": "[]"}, {"code": "H04L1/1812", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L1/1812", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04L5/0041", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/001", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/0058", "inventive": true, "first": true, "tree": "[]"}, {"code": "H04W24/10", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1812", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/1816", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/0041", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L1/189", "inventive": true, "first": false, "tree": "[]"}, {"code": "H04L5/001", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 53272252