BR112016015800B1 - METHOD AND APPARATUS FOR WIRELESS COMMUNICATION AND COMPUTER READABLE MEMORY - Google Patents

Abstract

CSI FEEDBACK FROM MULTIPLE SETS OF SUB-FRAMEWORKS. Certain aspects of the present disclosure relate to techniques and methods for reporting channel state information (CSI) feedback, for example, to UEs capable of supporting evolved interference management traffic adaptation (eIMTA).

Description

BACKGROUND Priority Claim

[0001] The present patent application claims priority to international application No. PCT/CN2014/070233, filed on January 7, 2014, and to international application No. PCT/CN2014/071952, filed on February 1, 2014 , both of which are assigned to the assignee thereof and expressly incorporated herein by way of reference.

Field

[0002] The present disclosure relates generally to wireless communication and, more specifically, to methods and equipment for providing channel state information (CSI) feedback using multiple sets of subframes.

Background

[0003] Wireless communication systems are widely deployed to provide various telecommunications services, such as telephony, video, data, message exchange, broadcast. Typical wireless communication systems may use multiple access technologies capable of supporting communication with multiple users by sharing available network resources (bandwidth, transmission power, for example). Examples of such multiple access technologies include Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, and Frequency Division Multiple Access (FDMA) systems. Orthogonal Frequency (OFDMA) and Single Carrier Frequency Division Multiple Access (SC-FDMA) systems and Synchronous Time Division Code Division Multiple Access (TD-SCDMA) systems.

[0004] These multiple access technologies have been adopted in various communication standards to provide a common protocol that allows different wireless devices to communicate at a municipal, national, regional and even global level. An example of an emerging telecommunications standard is Long Term Evolution (LTE). LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP). It is designed to better support mobile broadband Internet access by improving spectral efficiency, lower costs, enhancing services, making use of new spectrum, and better integrating with other standards that utilize OFDMA in the downlink (DL), SC-FDMA in uplink (UL) and multi-input, multi-output (MIMO) antenna technology. As demand for mobile broadband access continues to increase, however, there is a need for further improvements to LTE technology. Preferably, these improvements should be applicable to other multiple access technologies to telecommunications standards that use these technologies.

SUMMARY

[0005] Certain aspects of the present disclosure disclose a method for wireless communications by a user equipment. The method generally includes receiving signaling from a first uplink/downlink (UL/DL) subframe configuration for communicating with a base station (BS), receiving signaling from at least one channel state information reporting configuration (CSI) that indicates at least two sets of sub-frames, where each set of sub-frames is associated with an interference measurement resource (IMR) configuration, detecting a collision of CSI reports for the at least two sets of subframes in an uplink subframe, prioritize a set of subframes from the at least two sets of subframes for reporting CSI in the uplink subframe, and reporting CSI in the uplink subframe based on the prioritization .

[0006] Certain aspects of the present disclosure disclose equipment for wireless communications. The equipment may include at least one processor configured to receive signaling from a first uplink/downlink (UL/DL) subframe configuration for communication with a base station (BS), receive signaling from at least one information reporting configuration channel state information (CSI) that indicates at least two sets of subframes, where each set of subframes is associated with an interference measurement resource (IMR) configuration, detecting a collision of CSI reports to the at least least two sets of subframes in an uplink subframe, prioritize one set of subframes from the at least two sets of subframes for reporting CSI in the uplink subframe and reporting CSI in the uplink subframe based on prioritization, and a memory coupled with at least one processor.

[0007] Certain aspects of the present disclosure disclose equipment for wireless communications. The equipment generally includes a device for receiving signaling from a first uplink/downlink (UL/DL) subframe configuration for communication with a base station (BS), a device for receiving signaling from at least one reporting configuration of channel state information (CSI) that indicates at least two sets of subframes, where each set of subframes is associated with an interference measurement resource (IMR) configuration, a device for detecting a reporting collision of CSI for the at least two sets of subframes in an uplink subframe, a device for prioritizing a set of subframes of the at least two sets of subframes for reporting CSI in the uplink subframe, and reporting CSI in the uplink subframe based on prioritization, and a device for reporting CSI in the uplink subframe based on prioritization.

[0008] Certain aspects of the present disclosure disclose a non-transitory computer readable medium comprising instructions for receiving signaling from a first uplink/downlink (UL/DL) subframe configuration for communicating with a base station (BS). , receive signaling from at least one channel state information (CSI) reporting configuration that indicates at least two sets of subframes, where each set of subframes is associated with an interference measurement resource (IMR) configuration ), detect a collision of CSI reports for the at least two sets of subframes in an uplink subframe, prioritize a set of subframes from the at least two sets of subframes for reporting CSI in the uplink subframe uplink frame and report CSI in the uplink sub-frame based on prioritization.

[0009] Aspects generally include methods, equipment, systems, computer program product and processing systems, as substantially described herein with reference to and shown by the accompanying drawings. “LTE” generally refers to LTE and LTE-Advanced (LTE-A).

BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 is a diagram showing an example of a network architecture.

[0011] Figure 2 is a diagram showing an example of an access network.

[0012] Figure 3 is a diagram showing an example of a DL frame structure in LTE.

[0013] Figure 4 is a diagram showing an example of a UL frame structure in LTE.

[0014] Figure 5 is a diagram showing an example of a radio protocol architecture for the user and control planes.

[0015] Figure 6 is a diagram showing an example of an evolved NodeB and user equipment in an access network, in accordance with certain aspects of the disclosure.

[0016] Figure 7 shows a list of uplink/downlink subframe configurations.

[0017] Figure 8 shows an exemplary subframe frame format.

[0018] Figure 9 shows different IMR placement scenarios, according to certain aspects of the development.

[0019] Figure 10 shows 1000 exemplary operations for wireless communications, in accordance with certain aspects of the present disclosure.

[0020] Figure 11 shows exemplary operations 1100 for wireless communications, in accordance with certain aspects of the present disclosure.

[0021] Figure 12 shows the placement of IMRs in flexible sub-frames, in accordance with certain aspects of the present disclosure.

[0022] Figure 13 shows exemplary operations 1300 for wireless communication by a user equipment (UE), in accordance with certain aspects of the present disclosure.

[0023] Figure 14 shows an example of collision between two sets of sub-frames for reporting CSI in a UL sub-frame, in accordance with certain aspects of the present disclosure.

[0024] Figure 15 shows options for reporting when a valid DL subframe for measurement does not exist, in accordance with certain aspects of the present disclosure.

[0025] Figure 16 shows how an IMR subframe can change from DL to UL to perform dynamic subframe reconfiguration, in accordance with certain aspects of the present disclosure.

DETAILED DESCRIPTION

[0026] In some cases, time division duplexing (TDD) downlink/uplink (DL/UL) subframe configurations are dynamically adapted, for example, based on actual traffic needs and/or to help manage interference. This concept is sometimes referred to as evolved interference management for traffic adaptation (eIMTA).

[0027] In some cases, however, this adaptation may cause problems in measurements and reporting of channel state information (CSI). As an example, in some cases a dynamic reconfiguration may result in a subframe with resources used in CSI reporting that change from DL to UL. Consequently, a UE may not have a valid measurement to report. Aspects of the present disclosure present techniques for solving such problems with CSI measurements and CSI reporting for UEs capable of supporting dynamic subframe reconfiguration.

[0028] The detailed description presented below in connection with the attached drawings is intended to be a description of various configurations and is not intended to represent the only configurations in which the concepts described herein can be put into practice. The detailed description includes specific details for the purpose of providing a complete understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts can be put into practice without these specific details. In some cases, well-known structures and components are shown in the form of a block diagram in order to avoid obscuring such concepts.

[0029] Various aspects of telecommunications systems will now be presented with reference to various equipment and methods. These equipment and methods will be described in the following detailed description and shown in the attached drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as “elements”). These elements can be implemented using hardware, software or combinations thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the system as a whole.

[0030] By way of example, an element or any part of an element or any combination of elements can be implemented with a “processing system” that includes one or more processors. Examples of processors include microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gate-connected logic, discrete hardware circuits, and other suitable hardware configured to perform the various functionalities described throughout this disclosure. One or more processors in the processing system may execute software. Software will be interpreted broadly to mean instructions, instruction sets, code, code segments, program code, programs, sub-programs, application software modules, software applications. software packages, firmware, routines, subroutines, objects, executables, execution flows, procedures, functions, etc., whether referred to as software/firmware, middleware, micro-code, hardware description language or others.

[0031] Therefore, in one or more exemplary embodiments, the described functions can be implemented in hardware, software or combinations thereof. If implemented in software, functions can be stored or encoded as one or more instructions or code on a computer-readable medium. Computer readable media include storage media. Storage media can be any available media that can be accessed by a computer. By way of example and not limitation, such computer readable media may comprise RAM, ROM, EEPROM, PCM (phase change memory), flash memory, CD-ROM or other optical disk storage or magnetic disk storage. or other magnetic storage devices, any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), flexible disc, and Blu-ray disc, where discs usually reproduce data magnetically, while discs usually reproduce data optically with lasers, combinations of the above elements must also be included within the range of computer-readable media.

EXEMPLARY WIRELESS NETWORK

[0032] Figure 1 shows a wireless communications network 100 (an LTE network, for example), in which aspects of the present disclosure can be carried out. For example, the UE 102 may utilize the techniques described herein to resolve collisions that occur in CSI reporting and measurements for eIMTA LTE-based communications.

[0033] The wireless communications network 100 may be referred to as an Evolved Packet System (EPS) 100. The EPS 100 may include one or more user equipment (UEs) 102, a Terrestrial Radio Access (UMTS) network EPS (E-UTRAM) 104, an Evolved Packet Core (EPC) 110. A Native Subscriber Server (HSS) 120, a Carrier IP Service 122. The EPS can interconnect with other access networks, but for simplification , these entities/interfaces are not shown. Other exemplary access networks may include an IP Multimedia Subsystem (IMS) PDN, Internet PDN, Administrative PDN (Supply PDN, for example), Carrier Specific PDN, Carrier Specific PDN, and GPS PDN. As shown, EPS provides packet-switched services, but as will be readily understood by those skilled in the art, the various concepts presented throughout this disclosure can be extended to networks that provide circuit-switched services.

[0034] The E-UTRAM includes the Evolved Node B (eNB) 106 and other eNBs 108. The eNB provides user and control plane protocol terminations towards the UE 102. The eNB 106 can be connected to the other eNBs 108 via an X2 interface (return transport channel, for example). The eNB 106 may also be referred to as a base station, base transceiver station, radio base station, radio transceiver, transceiver function, basic service set (BSS), extended service set (ESS), access point, or some other appropriate terminology. The eNB 106 may provide an access point to the EPC 110 for a UE 102, examples of UEs 102 include a cell phone, a smart phone, a session initiation protocol (SIP) phone, a laptop, a personal digital assistant (PDA) ), a satellite radio, a global positioning system, a multimedia device, a video device, a digital audio player (an MP3 player, for example), a camera, a game console, a tablet, a netbook , a smartbook, an ultrabook or any similar device. The UE 102 may also be referred to by those skilled in the art as a mobile station, subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, remote apparatus, wireless apparatus, wireless communication apparatus, remote apparatus, station of mobile subscriber, access terminal, mobile terminal, wireless terminal, remote terminal, telephone handset, user agent, mobile client, client or some other suitable terminology.

[0035] The eNB 106 is connected via an S1 interface to the EPC 110. The EPC 110 includes a Mobility Management Entity (MME) 112, other MMEs 114, a Serving Gateway 116, and a Packet Data Network Gateway (PDN ) 118. The MME 112 is a control mode that processes signaling between the UE 102 and the EPC 110. Generally the MME 112 provides carrier and connection management. All IP packets are transferred through the Server Gateway 116, which is itself connected to the PDN Gateway 118. The PDN Gateway 118 provides UE IP address allocation as well as other functions. The PDN Gateway 118 is connected to the carrier's IP services 122. Carrier IP Services 122 may include, for example, the Internet, the Intranet, an IP Multimedia Sub-System (IMS), and a Streaming (PS) (packet-switched) Service (PSS). In this way, the UE 102 can be coupled to the PDN via the LTE network.

[0036] Figure 2 is a diagram showing an example access network 200 in an LTE network architecture, in which aspects of the present disclosure can be carried out. For example, the UE 206 may utilize the techniques described herein to resolve collisions that occur in CSI reporting and measurements for eIMTA LTE-based communications.

[0037] In the example shown, the access network 200 is divided into several cellular regions (cells) 202. One or more lower power class eNBs 208 may have cellular regions 210 that overlap one or more of the cells 202. A lower power class 208 eNB may be referred to as a remote radio head (RRH). The lower power class eNB 208 may be a femto-cell (native eNB (HeNB)), pico-cell or micro-cell. The macro-eNBs 204 are each assigned to a respective cell 202 and are configured to provide an access point to the EPC 110 for all UEs 206 in cells 202. There is no centralized controller in this example access network 200 , but a centralized controller can be used in alternative configurations. The eNBs 204 are responsible for all radio-related functions, which include radio-carrier control, admission control, mobility control, scheduling, security, and connectivity with the Gateway Server 116. The network 200 may also include one or more relays (not shown). According to one application, a UE can function as a relay.

[0038] The modulation and multiple access scheme used by access network 200 may vary depending on the specific telecommunications standard that is deployed. In LTE applications, OFDM is used in the DL and SC-FDMA is used in the UL to support both frequency division duplexing (FDD) and time division duplexing (TDD). As will be readily understood by those skilled in the art from the following detailed description, the various concepts presented herein are well suited for LTE applications. However, these concepts can be readily extended to other telecommunications standards that use other modulation and multiple access techniques. As an example, these concepts can be extended to Evolution-Optimized Data (EV-DO) or Ultra-Mobile Broadband (UMB). EV-DO and UMB are air interface standards promulgated by the 3rd Generation Partnership Project 2 (3GPP2) as part of the CDMA2000 family of standards and use CDMA to provide broadband Internet access to mobile stations. These concepts can also be extended to Universal Terrestrial Radio Access (UTRA), which uses Wideband CDMA (W-CDMA) and other variants of CDMA, such as TD-SCDMA; the Global System for Mobile Communications (GSM) which uses TDMA; and Evolved UTRA (E-UTRA), Ultramobile Broadband (IEEE) 802.11 (WiFi), IEEE 802.16 (WiMAX) IEEE 802.20 and Flash-OFDM that uses OFDMA. UTRA, E-UTRA, UMTS, LTE and GSM are described as 3GPP organization documents. CDMA2000 and UMB are described in documents from the 3GPP2 organization. The actual wireless communication standard and multiple access technology used will depend on the specific application and design constraints imposed on the system.

[0039] The eNBs 204 may have multiple antennas that support MIMO technology. The use of MIMO technology allows eNBs 204 to explore the spatial domain to support spatial multiplexing, beamforming, and transmission diversity. Spatial multiplexing can be used to transmit different streams of data simultaneously on the same frequency. Data streams can be transmitted to a single UE 206 to increase the data rate or to multiple UEs 206 to increase the capacity of the total system. This is achieved by spatially pre-coding each data stream (applying amplitude and phase scaling, for example) and then transmitting each spatially pre-coded stream through multiple transmit antennas in the DL. The spatially pre-coded data streams arrive at the UEs 206 with different spatial signatures, which allow each of the UEs 206 to retrieve the data stream or streams intended for that UE 206. In the UL, each UE 206 transmits a data stream spatially pre-coded, which allows the eNB 204 to identify the source of each spatially pre-coded data stream.

[0040] Spatial multiplexing is generally used when channel conditions are good. When channel conditions are less favorable, beamforming can be used to focus transmission energy in one or more directions. This can be achieved by spatial pre-coding of data for transmission over multiple antennas. In order to obtain good coverage at the cell edges, single-stream beamforming transmission can be used in combination with transmission diversity.

[0041] In the detailed description that follows, various aspects of an access network will be described with reference to a MIMO system that supports OFDM in the DL. OFDM is a spread spectrum technique that modulates data across multiple sub-carriers within an OFDM symbol. The sub-carriers are spaced apart at precise frequencies. The spacing provides “orthogonality” that allows a receiver to recover data from subcarriers. In the time domain, a protection interval (a cyclic prefix, for example) can be added to each OFDM symbol to combat inter-OFDM symbol interference. UL can utilize SC-FDMA in the form of an OFDM signal with DFT spread to compensate for peak-to-average power ratio (PAPR).

[0042] Figure 3 is a diagram 300 showing an example of a DL frame structure in LTE. One frame (10 msec) can be divided into 10 equally sized subframes with indices from 0 to 9. Each subframe can include two consecutive time partitions. A resource grid can be used to represent two time partitions, each time partition including a resource block. The resource grid is divided into several resource elements. In LTE, a resource block contains 12 consecutive subcarriers in the frequency domain and, for a normal cyclic prefix in each OFDM symbol, 7 consecutive OFDM symbols in the time domain, or 84 resource elements. For an extended cyclic prefix, a resource block contains 6 consecutive OFDM symbols in the time domain and has 72 resource elements. Some of the resource elements indicated as R 302, R 304, include DL reference signals (DL-RS). The DL-RS include Cell-specific RS (CRS) (also sometimes called common RS) 302 and UE-specific RS (UE-RS) 304. The UE-RS 304 are transmitted only in the resource blocks in which the shared channel Corresponding physical DL (PDSCH) is mapped. The number of bits carried by each resource element depends on the modulation scheme. Thus, the more resource blocks a UE receives and the higher the modulation scheme, the higher the data rate for the UE.

[0043] In LTE, an eNB can send a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) to each cell in the eNB. The primary and secondary synchronization signals can be sent in symbol periods 6 and 5 respectively, in each of subframes 0 and 5 of each radio frame with the normal cyclic prefix (CP). Synchronization signals can be used by UEs for cell detection and acquisition. The eNB can send a physical broadcast channel (PBCH) in symbol periods 0 to 3 in partition 1 of subframe 0. The PBCH can carry certain system information.

[0044] The eNB may send a physical control format indicator channel (PCFICH) in the first symbol period of each subframe. The PCFICH can transmit the number of symbol periods (M) used for control channels, where M can be equal to 1, 2 or 3 and can change from sub-frame to sub-frame. M can also be equal to 4 for a small system bandwidth, such as less than 10 resource blocks. The eNB can send a Physical HARQ indicator channel (PHICH) and a physical downlink control channel (PDCCH) in the first M symbol periods of each subframe. PHICH can carry information to support hybrid automatic retry request (HARQ). The PDCCH can carry resource allocation information for UEs and control information for downlink channels. The eNB can send a physical downlink shared channel (PDSCH) in the remaining symbol periods of each subframe. The PDSCH can carry data to UEs scheduled for downlink data transmission.

[0045] The eNB can send the PSS, the SSS and the PBCH in the central 1.8 MHz of the system bandwidth used by the eNB. The eNB can send PCFICH and PHICH across the entire system bandwidth in each symbol period in which these channels are sent. The eNB can send the PDCCH to groups of UEs in certain parts of the system bandwidth. The eNB can send the PDSCH to specific UEs in specific parts of the system bandwidth. The eNB can send PSS, SSS, PBCH, PCFICH and PHICH in broadcast manner to all UEs, can send PDCCH in unicast manner to specific UEs, and can also send PDSCH in unicast manner to specific UEs .

[0046] Various resource elements may be available in each symbol period. Each resource element (RE) can cover a sub-carrier in a symbol period and can be used to send a modulation symbol, which can be a real or complex value. Unused resource elements for a reference signal in each symbol period can be arranged into resource element groups (REGs). Each REG can include four resource elements in a symbol period. The PCFICH may occupy four REGs, which may be spaced approximately equally apart across the frequency, in symbol period 0. The PHICH may occupy three REGs, which may be spread across the frequency, in one or more configurable symbol periods. For example, the three REGs for PHICH can all belong to symbol period 0 and can be spread across symbol periods 0, 1 and 2. PBCH can occupy 9, 18, 36 or 72 REGs that can be selected from the REGs available, in the first periods of M symbols, for example. Only certain combinations of REGs can be allowed for PDCCH. In the light of the present methods and apparatus, a subframe may include more than one PDCCH.

[0047] A UE may know the specific REGs used for PHICH and PCFICH. The UE can search different combinations of REGs for the PDCCH. The number of combinations to be,fetched is typically less than the number of combinations,allowed for the PDCCH. An eNB can send the PDCCH to the UE in any of the combinations that the UE will fetch.

[0048] Figure 4 is a diagram 400 showing an example of a UL frame structure in LTE. The resource blocks available to the UL can be partitioned into a data section and a control section. The control section can be formed on both edges of the system bandwidth and can have a configured size. Resource blocks in the control section can be assigned to UEs for transmitting control information. The data section can include all resource blocks not included in the control section. The UL frame structure results in the inclusion of contiguous subcarriers in the data section, which may allow a single UE to be assigned all contiguous subcarriers of the data section.

[0049] A UE may be assigned resource blocks 410a, 410b in the second section for transmitting control information to an eNB. The UE may also be assigned resource blocks 420a, 420b in the data section for transmitting data to the eNB. The UE can transmit control information on a physical UL control channel (PUCCH) in the resource blocks assigned in the control section. The UE may transmit only data or both data and control information on a physical UE shared channel (PUSCH) in the resource blocks assigned in the data section. A UL transmission can span both partitions of a subframe and can hop across frequency.

[0050] The set of resource blocks can be used to perform initial access to the system and achieve UL synchronization on a physical random access channel (PRACH) 430. The PRACH 430 carries a random sequence and cannot carry any UL data/signaling . Each random access preamble occupies a bandwidth corresponding to six consecutive resource blocks. The starting frequency is specified by the network. That is, transmission of the random access preamble is restricted to certain time and frequency resources. There is no frequency hopping for PRACH. The PRACH attempt is carried in a single sub-frame (1 msec) or in a sequence of a few contiguous sub-frames and a UE can make only a single PRACH attempt per frame (10 msec).

[0051] Figure 5 is a diagram 500 showing an example of a radio protocol architecture for the user and control planes in LTE. The radio protocol architecture for the UE and eNB is shown with three layers: Layer 1, Layer 2 and Layer 3. Layer 1 (L1 layer) is the lowest layer and implements several signal processing functions physical layer. The L1 layer will be referred to herein as the physical layer 506. Layer 2 (L2 layer) 508 sits above the physical layer 506 and is responsible for the link between the UE and the eNB through the physical layer 506.

[0052] In the user plane, the L2 layer 508 includes a media access control (MAC) sub-layer 510, a radio link control (RLC) sub-layer 512 and a radio link protocol sub-layer 512. packet data convergence (PDCP) 514 that are terminated in the eNB on the network side. Although not shown, the UE may have several upper layers above the L2 layer that include a network layer (IP layer) that is terminated at the PDN Gateway 118 on the network side and an application layer that is terminated at the other end of the connection ( far-end UE, server, etc., for example).

[0053] The PDCP sub-layer 514 provides multiplexing between different radio carriers and logical channels. The PDCP sublayer 514 also provides header compression for higher layer data packets to reduce radio transmission overhead. Security through data packet encryption and handover support for UEs between eNBs. The RLC sublayer 512 provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to the HARQ hybrid autoretry request. The MAC sublayer 510 provides multiplexing between logical and transport channels. The MAC sublayer 510 is also responsible for allocating the various radio resources (resource blocks, for example) in a cell between the UEs. The MAC sublayer 510 is also responsible for HARQ operations.

[0054] In the control plane, the radio protocol architecture for the UE and the eNB is substantially the same for the physical layer 506 and the L2 layer 508, with the exception that there is no header compression function for the plane of control. The control plane also includes a radio resource control (RRC) sublayer 516 at Layer 3 (L3). The RRC sub-layer 516 is responsible for obtaining radio resources (i.e., radio carriers) and configuring the lower layers using RRC signaling between the eNB and the UE.

[0055] Figure 6 is a block diagram of an eNB 610 communicating with a UE 650 in an access network, in which aspects of the present disclosure can be carried out. For example, the UE 650 may utilize the techniques described herein to resolve collisions that occur in CSI reporting and measurements for eIMTA LTE-based communications.

[0056] In the DL upper layer packets of the basic network are sent to a controller/processor 675. The controller/processor 675 implements the functionality of the L2 layer. In the DL, the controller/processor 675 provides header compression, encryption, packet segmentation and reordering, multiplexing between logical and transport channels, and radio resource allocations to the UE 650 based on various priority metrics. The controller/processor 675 is also responsible for HARQ operations, retransmission of lost packets, and signaling to the UE 650.

[0057] The TX 616 processor implements various signal processing functions for the L1 layer (i.e., physical layer). Signal processing functions include condition and interleaving to facilitate forward error correction (FEC) in the UE 650 and mapping into signal constellations based on various modulation schemes (binary phase key shift keying (BPSK), quadrature key shift keying (QPSK), M phase shift keying (M-PSK), M quadrature amplitude modulation (M-QAM)). The encoded and modulated symbols are then split into parallel streams. Each flow is then mapped onto an OFDM sub-carrier, multiplexed with a reference signal (pilot, for example) in the time and/or frequency domain, and then combined together using an inverse Fast Fourier transform. (IFFT) to produce a physical channel that carries a stream of OFDM symbols in the time domain. The OFDM stream is spatially pre-coded so that several spatial streams are produced. Channel estimates from a channel estimator 674 can be used to determine the coding and modulation scheme, as well as for spatial processing. The channel estimate may be derived from a reference signal or channel condition feedback transmitted by the UE 650. Each spatial stream is then sent to a different antenna 620 via a separate transmitter 618TX. Each 618TX transmitter modulates an RF carrier with a respective spatial flow for transmission.

[0058] In UE 650, each receiver 654RX receives a signal through its respective antenna 652. Each receiver 654RX retrieves information modulated on an RF carrier and provides the information to the receive processor (RX) 656. The RX processor 656 implements several functions L1 layer signal processing. The RX processor 656 performs spatial processing on the information in order to recover any spatial streams destined for the UE 650. If multiple spatial streams are destined for the UE 650, they can be combined by the RX processor 656 into a single OFDM symbol stream. The RX 656 processor then converts the stream of OFDM symbols from the time domain to the frequency domain using a Fast Fourier transform (FFT). The frequency domain signal comprises a separate OFDM symbol stream for each sub-carrier of the OFDM signal. The symbols on each subcarrier and the reference signal are recovered and demodulated by determining the most likely signal constellation points transmitted by the eNB 610. These temporary decisions may be based on channel estimates computed by the channel estimator 658. Temporary decisions are then decoded and deinterleaved to recover the data and control signals that were originally transmitted by the eNB 610 on the physical channel. The data and control signals are then sent to the 659 controller/processor.

[0059] Controller/processor 659 implements the L2 layer. The controller/processor may be associated with a memory 660 that stores program codes and data. Memory 660 may be referred to as a computer-readable medium. In UL, the 659 controller/processor provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover higher layer packets from the core network. The upper layer packets are then sent to a data store 662, which represents all protocol layers above the L2 layer. Various control signals may also be sent to data store 662 for L3 processing. The 659 controller/processor is also responsible for detecting errors using an acknowledgment (ACK) and/or negative acknowledgment (NACK) protocol to support HARQ operations.

[0060] In the UL, a data source 667 is used to send higher layer packets to the controller/processor 659. The data source 667 represents all protocol layers above the L2 layer. Similar to the functionality described in connection with DL transmission by eNB 610, controller/processor 659 implements the L2 layer for the user plane and control plane providing header compression, encryption, packet segmentation and reordering, and multiplexing between logical and transport channels based on radio resource allocations by the eNB 610. The controller/processor 659 is also responsible for HARQ operations, retransmission of lost packets and signaling to the eNB 610.

[0061] Channel estimates derived by a channel estimator 658 from a reference or feedback signal transmitted by the eNB 610 may be used by the TX processor 668 to select appropriate coding and modulation schemes and to facilitate spatial processing. The spatial streams generated by the TX processor 668 are sent to different antennas 652 via separate TX transmitters 654. Each 654TX transmitter modulates an RF carrier with a respective spatial flow for transmission.

[0062] The UL transmission is processed in the eNB 610 in a manner similar to that described in connection with the receiver function in the UE 650. Each receiver 618 RX receives a signal through its respective antenna 620. Each receiver 618 RX recovers modulated information in a RF carrier and sends the information to an RX 670 processor. The RX 670 processor can implement the L1 layer.

[0063] Controller/processor 675 implements the L2 layer. The controller/processor 675 may be associated with a memory 676 that stores program codes and data. Memory 676 may be referred to as a computer-readable medium. In the UL, the controller/processor 675 provides demultiplexing between transport and logical channels, packet reassembly, decryption, header decompression, control signal processing to recover higher layer packets from the UE 650. Higher layer packets from the controller/processor can be sent to the basic network. The 675 controller/processor is also responsible for error detection that uses an ACK and/or NACK protocol to support HARQ operations.

[0064] Controllers/processors 675, 659 may direct operation in the eNB 610 and UE 650 respectively, to operate in accordance with certain aspects of the present disclosure. For example, the controller/processor 659 and/or other processors and modules in the UE 650 may perform or direct the UE to perform the operations 1100 shown in Figure 11 and/or the operations 1300 shown in Figure 13. Likewise, the controller /processor 675 and/or other processors and modules in the eNB 610 may perform or direct the eNB 610 to perform the operations 1000 shown in Figure 10.

EXEMPLARY SUB-FRAME CONFIGURATIONS

[0065] Figure 7 shows an exemplary frame structure 700 for TDD LTE. As shown in Figure 7, the 10 msec radio frame 702 consists of two half-frames 704 of equal length (5 msec, for example), with each half-frame consisting of 10 partitions or 8 partitions (partition 706, for example ) plus three special fields DwPTS (Downlink pilot time partition, GP (protection period) and UpPTS (uplink pilot time partition) in a special subframe 708. Each partition 706 is 0.5 msec of length and two consecutive partitions form exactly one subframe 710.

[0066] Within a frame radio, TDD LTE switches multiple times between downlink and uplink transmissions and vice versa. The protection period (GP) is inserted between DwPTS and UpPTS when switching from downlink to uplink. The GP duration depends on the signal propagation time from a base station to a mobile station and back, as well as the time the mobile station requires to switch from receiving to sending. The lengths of the individual special fields depend on the uplink/downlink configuration selected by the network, but the total length of the three special fields remains constant at 1 msec.

[0067] In TDD LTE, transmission directions are separated by carrying UL and DL data in different sub-frames. Seven possible DL and UL subframe configurations are supported, as shown in table 800 of Figure 8.

[0068] As shown in column 802 of table 800, the 7 UL/DL configurations are identified by indexes 0-6. As shown in column 806, a “D” in a subframe indicates DL data transmission, “U” indicates UL data transmission, and “S” indicates a special subframe that has special fields DwPTS, GP, and UpPTS as discussed above with reference to Figure 7. As shown in column 804, there are two switching periodicities, 5 msec and 10 msec. For the 5 msec periodicity (the 0-2 and 6 subframe configurations, for example), there are two special subframes in a 10 msec frame - as shown in Figure 7. For the 10 msec periodicity (the subframe settings 3-5, for example), there is a special subframe in a frame. CSI FEEDBACK OF TWO SUB-FRAME SETS FOR eIMTA ON LTE

[0069] UEs that support dynamic subframe configurations, as with eIMTA, may experience certain challenges when measuring and reporting CSI. Aspects of the present invention present techniques that can be used for reporting CSI by UEs capable of supporting dynamic subframe reconfiguration.

[0070] To facilitate CSI reporting, certain standards (LTE Release 11, for example) have introduced the UE-specific interference measurement (IMR) feature that allows a UE to report measurements that can help an eNB determine the interference conditions. In some cases, UEs can be configured with separate IMRs based on certain parameters, such as the SubframeConfig and resourceConfig parameters. The subframeConfig parameter signals which subframes contain the IMR and has a co-coded periodicity and subframe offset. The resourceConfig parameters identify which resource elements (REs) are occupied by a non-zero power (NZP) Channel State Information Reference Signal (CSI-RS) resource (that is, the pattern that is used).

[0071] In conventional systems, IMR programming may be subject to additional restrictions. For example, a first restriction is that all IMRs configured for a UE may be a subset of a virtual zero power (ZP) CSI-RS configuration, which may or may not actually be configured for the specific UE. A second restriction is that each IMR configured for a UE can be covered by at least one CSI-RS ZP resource configured for that UE, but IMRs configured for a UE do not necessarily have to be covered by the same CSI-RS ZP configuration. RSZP.

[0072] As shown in Figure 9, the first constraint requires that all IMRs fit within a 5 msec grid. For example, Figure 9 shows two scenarios of when IMRs are allowed and one scenario of when IMRs are not allowed due to the first restriction noted above. As can be seen in scenario 1, two IMRs (IMR1 and IMR2) can be allowed when both are included at the same time in the same subframe and are in multiples of 5 msec. Scenario 2 shows that IMR1 and IMR2 are allowed when they are scaled on a 5 msec grid. For example, IMR1 snaps at 0 msec and IMR2 snaps at 5 msec. Scenario 3 shows an example of when IMRs are not allowed because the two IMRs do not fit into the 5 msec grid.

[0073] As noted above, using eIMTA, it is possible to adapt DL/UL TDD subframe configurations based on actual traffic needs and/or for interference management purposes. For example, if, for a short duration, a large burst of data on the downlink is required, the subframe configuration can be changed, for example, from configuration No.1, which has six DL subframes and four subframes. -UL frames, for configuration N°.5, which has nine DL sub-frames and one UL sub-frame. In some cases, adapting a TDD configuration is expected to be no slower than 640 msec. In an extreme case, adaptation can be as fast as 10 msec.

[0074] In some cases, for eIMTA, up to two sets of sub-frames may be signaled specifically to UE to allow separate channel state information (CSI) measurements/reporting for one or the other of the two sets of sub-frames. However, in order to support CSI measurements/reporting for two subframe types, it may be necessary to remove the first IMR restriction (that all IMRs fall within a 5 msec grid) for eIMTA. Thus, there may be a need to define when this restriction can be removed at least for eIMTA capable UEs.

[0075] Figure 10 shows 1000 exemplary operations for wireless communications, in accordance with aspects of the present disclosure. According to the aspects, operations 1000 may be performed by a base station (by an eNodeB, for example).

[0076] Operations 1000 begin, at 1002, by signaling a first uplink/downlink (UL/DL) subframe configuration to a user equipment (UE). At 1004, the BS dynamically signals a second UL/DL subframe configuration. At 1006, the BS configures the UE with at least one first and one second interference measurement resources (IMRs) wherein at least one of the first and second IMRs is not subject to the restriction that the IMRs be limited to subframes that occur periodically.

[0077] Figure 11 shows exemplary operations 1100 for wireless communications, in accordance with aspects of the present disclosure. According to the aspects, operations 1100 may be performed by a UE.

[0078] Operations 1100 begin, at 1102, by receiving signaling from a first uplink/downlink (UL/DL) subframe configuration for communication with a base station (BS). At 1104, the UE receives dynamic signaling from a second UL/DL subframe configuration of the BS. At 1106, the UE is provided with a configuration of at least one first and one second interference measurement resources (IMRs) wherein at least one of the first and second IMRs is not subject to the restriction that the IMRs be limited to subframes that occur periodically.

[0079] According to certain aspects of the present disclosure, one or more restrictions on IMRs can be removed. For example, in some cases, the restriction that IMRs must adhere to a 5 msec grid can be removed for eIMTA capable UEs. In some cases, this restriction can be removed only on flexible subframes (referring to subframes with directions that can be dynamically changed from UL to DL and vice versa). In some cases, however, it may be beneficial to continue to require all IMRs to fall within a 5 msec grid, to help accommodate legacy users.

[0080] However, it is possible to place a second IMR (IMR-2) on subframes that are not designated as DL subframes in a SIB1-signaled configuration, such as flexible subframes 1202 that are not recognized by UEs legacies. For example, Figure 12 shows that it is possible to place the IMR-2 on flexible subframes 1202 that do not adhere to a 5 msec grid. In certain respects, the placement of IMR-2 in non-SIB1 subframes can ensure that a two-IMR configuration only applies to UEs capable of supporting eIMTA.

COLLISION PROCESSING OF CSI REPORTS

[0081] As noted above, eIMTA can cause problems with channel state information (CSI) measurements and reporting.

[0082] For example, for certain subframe configurations and CSI reporting configuration, CSI measurements for different CSI reporting processes can be configured to be reported in the same UL subframe (herein referred to as “collision ”). This may present a problem, for example, in scenarios where a single report may be sent in a UL subframe. Aspects of the present disclosure present techniques for prioritizing the measurement that should be reported.

[0083] Furthermore, due to various reasons, the UE may not be able to detect a valid DL sub-frame (or there may be no valid DL sub-frame) to perform CSI measurements. For example, due to eIMTA, a DL subframe configured to contribute resources for CSI measurement can be dynamically changed to a UL subframe. Aspects of the present disclosure present techniques for determining how to report CSI in cases where the current subframe configuration is not compatible (or “collides”) with the current CSI configuration, which may also be considered a “collision”.

[0084] Figure 13 shows 1300 exemplary operations for wireless communication, in accordance with aspects of the present disclosure. Operations 1300 may be performed, for example, by a UE capable of supporting eIMTA.

[0085] Operations 1300 begin, at 1302, by receiving signaling from a first uplink/downlink (UL/DL) subframe configuration for communication with a base station (BS). At 1304, the UE receives signaling from at least one channel state information (CSI) reporting configuration that indicates at least two sets of subframes, where each set of subframes is associated with a measurement resource configuration. interference response (IMR). At 1306, the UE detects a collision of CSI reports for the at least two subframe sets in an uplink subframe. At 1308, the UE prioritizes a set of subframes from the at least two sets of subframes for CSI reporting in the uplink subframe. At 1310, the UE reports CSI in the uplink subframe based on prioritization.

[0086] As described above, periodic reporting of CSI for two sets of subframes can also be supported under eIMTA. According to certain aspects, when there is a collision between CSI reports for the two sets of subframes (that is, each set of subframes is configured to report on the same UL subframe), one of the sets of subframes is -Tables may be given priority for reporting purposes.

[0087] In some cases, a fixed subframe set CSI (with the CSI being measured on subframes that are “fixed” like DL subframes as opposed to “flexible” subframes that can be reconfigured ) may be given a higher priority. This may be necessary since for periodic CSI reports sent on PUCCH, only one report can be transmitted on PUCCH and all others can be discarded.

[0088] Aspects of the present disclosure present different options for prioritizing reports when a collision between periodic CSI processes is detected. For example, for collisions within a component carrier (CC), prioritization can be carried out based on the following order: first considering the type of report (RI/PTI/CQI, for example), then the set of sub -CSI frames (CSI0 or CSI1, for example), then the CSI process index. For collisions across multiple CCs, for eIMTA with carrier aggregation (CA), prioritization can also consider the specific CC. For example, prioritization for eIMTA CA can be carried out based on the following order: first considering the report type, then the set of CSI sub-frames, then the CSI process index and finally the CSI process index. CC. In certain aspects, CSI reporting for fixed subframes can be considered as CSI process ID No.0, which can allow existing collision processing rules to be reused for eIMTA.

[0089] Figure 14 shows an example of collisions between two sets of sub-frames for CSI reporting. In the example shown, a first set of subframes (Subframe Set 1) has a reporting periodicity of 10 msec and is configured to report CSI measurements in subframes 2, 12, 22, and so on. A second set of subframes (Subframe Set 2) has a CSI reporting periodicity of 5 msec and is configured to report CSI measurements in subframes 2, 7, 12, 22, and so on. Thus, as shown, Subframe Sets 1 and 2 are both configured to report CSI in subframes 2, 12, and 22 resulting in a collision.

[0090] As noted above, a collision between sets of subframes can occur when both sets of subframes are configured to report CSI measurements on the same UL subframe. In order to resolve this collision, the UE may determine which set of subframes should be prioritized for CSI reporting in the colliding UL subframe. When only one set of subframes (Subframe Set 2, for example) is configured to report CSI measurements within a specific UL subframe (UL SFs 7, 17, and 27, for example), no collisions occur and the UE can report CSI for that set of subframes.

[0091] For both periodic (P-CSI) and aperiodic (A-CSI) (i.e., non-periodic) CSI reports, the UE may require a valid DL subframe (with resources allocated to signals reference) to measure CSI. A DL subframe may be considered valid, for example, if it is configured as a downlink subframe for a specific UE, if it does not fall within a configured measurement range for that specific UE, and if it is an element of the set of CSI subframes connected to the CSI report. In certain respects, if there was no valid downlink subframe for CSI measurement in a serving cell, a CSI report may be omitted for the serving cell in the corresponding uplink subframe (in which that CSI would have been reported).

[0092] In certain aspects, for normal TDD operation, parameters for determining whether a DL subframe is valid can be configured semi-statically, which reduces ambiguity between the eNB and the UE. However, for eIMTA TDD there can be dynamic subframe direction configuration between the UL and the DL. If a UE is unable to decode Layer 1 (L1) signaling for dynamic configuration, incorrect alignment between the eNB and the UE, in terms of subframe direction, may occur, thereby affecting CSI measurement and reporting. For example, the eNB may dynamically signal to the UE a new subframe configuration, which includes at least one DL subframe in which the UE is expected to make CSI measurements. However, if the UE cannot properly decode the dynamic signaling, the UE may think that the at least one DL subframe is a UL subframe and may not be able to make CSI measurements.

[0093] Several approaches can be used to measure CSI for eIMTA TDD. According to one approach, when a UE decodes the explicit L1 reconfiguration signaling correctly and detects a valid UL-DL configuration, the UE can measure the CSI only within the subframes indicated as DL subframe or special subframe by the explicit L1 reconfiguration signaling. On the other hand, if the UE does not detect L1 signaling that transmits a valid UL-DL configuration for a radio frame, the UE may measure CSI only within subframes indicated as DL subframe or special subframe by a configuration of SIB, which can be considered a fallback operation (i.e., when the UE cannot decode the L1 signaling, the UE can fall back to the SIB configuration).

[0094] However, the above approach to reporting CSI may result in omission of CSI for flexible DL subframes if the UE does not detect L1 signaling that transmits a UL/DL configuration. This may cause ambiguity in an eNB that expects CSI reported by the UE, but does not actually receive a CSI report from the UE (due to the backoff operation described above, for example). This can also affect PUSCH decoding when CSI is multiplexed into PUSCH, especially for multiple component carriers (CCs) configured for a UE, since PUSCH data rate matching is highly dependent on the number of aggregated CSI bits. and the number of CCs aggregated for CSI reporting.

[0095] In certain respects, a UE may take steps to determine how to report when it has no valid DL subframe to measure. For example, the UE may send an outdated CSI measurement for periodic CSI reporting when a CSI DL reference subframe is reconfigured from DL to UL. This can also be applied to CSI reporting to journals (A-CSI). For example, a UE may report a previous CSI value or an out-of-range (OOR) CSI value when the UE receives an A-CSI trigger and the CSI measurement reference subframe is changed from DL to UL . However, this may violate the existing condition for CSI reporting (i.e., that CSI measurements are based on the valid DL subframe). Thus, it may be beneficial to not solely base CSI reporting on the condition of a valid DL subframe used for CSI measurement.

[0096] In certain aspects, the UE may omit a CSI report, report a previous CSI measurement, or report a value that is out of range (OOR) when there is no valid DL subframe for CSI measurement. This new definition can also be extended to multiple CCs (i.e., multiple component carriers) in which the HARQ DL reference configuration is CC specific. Determining a valid DL subframe for CSI measurements from an RRC-configured HARQ DL reference configuration can provide alignment between the eNB and the UE in terms of CSI reporting during the UE backoff operation since the DL reference configuration is semi-statically configuration.

[0097] Figure 15 shows an example of a collision that occurs for CSI measurements and how a UE can determine whether a valid DL subframe exists for CSI reporting, in accordance with certain aspects of the present disclosure.

[0098] The example shown assumes that subframes (SFs) 0, 1, 5 and 6 are fixed DL SFs and that SFs 2 and 7 are fixed UL SFs. The example also assumes that the remaining subframes are flexible SFs that can be UL or DL depending on a dynamic indicator. In certain aspects, in Frame n, a UE may detect and appropriately decode a dynamic indicator for Frame n in SF DL 0. The UE may then report A-CSI during SF UL 7 with the CSI measured in SF DL 3 flexible.

[0099] According to other aspects, in Frame n+1, the UE may not be able to decode the dynamic indicator and may introduce the SIB backoff operation where the flexible SF3 may be assumed to be UL although it is actually used as DL by the eNB. In this case, the UE may assume that there is no valid DL subframe for CSI reporting. Based on the existing CSI reporting condition, the UE may omit the CSI reporting during SF 7 (for CSI measurement in SF3) although it is requested by the eNB since there is no valid DL subframe.

[0100] In certain respects, however, the UE may know to report CSI in SF 7, since SF 3 is a valid DL subframe for CSI reporting based on the HARQ DL 2 reference configuration as shown in Figure 14. Thus, even if a valid DL subframe does not exist for CSI reporting, the UE can still transmit a CSI report (with a measurement value that is out of date or OOR, for example) instead of the measurement values. CSI taken by SF 3.

[0101] Figure 16 also shows how a UE may lack a valid DL subframe for CSI reporting due to eIMTA. Similar to the example shown in Figure 14, the example shown in Figure 16 assumes that the CSI measurements for Subframe Set 2 are configured to occur in subframes 3 and 8 (IMR2 is in SF3 and SF8) . The example also assumes that the HARQ DL reference configuration is based on the subframe 2 configuration (DSUDDDSUDD).

[0102] In a first frame 1602, as indicated by the dashed lines in SFs 0-9, the UE may not have yet received a dynamic indicator (i.e., an eIMTA configuration dynamically signaled by L1). In this case, the UE can rely on the configuration of SIB1 to determine whether a collision has occurred and whether a valid DL subframe exists. As shown in Table 1602, both the SIB1 configuration and the HARQ DL reference configuration indicate subframes 3 and 8 as a downlink subframe. Thus, in this case, the UE has a valid DL subframe for CSI measurements (which can be considered as collisionlessness). Thus, the UE can measure CSI in subframes 3 and 8 and then report CSI based on these measurements (report in SF7 and SF 12, respectively, for example).

[0103] In frame 1604, however, the UE receives and appropriately decodes an elMTA subframe configuration (indicating SF configuration No.6, for example). In this case, the reconfiguration changed SF3 and SF8 from DL to UL. Consequently, the UE has no valid DL subframe for CSI reporting. Thus, the UE may consider this a collision (since the SF dynamic configuration collides with the CSI reporting configuration) and report accordingly (omit a report, report a previous measurement or report an OOR value, for example) .

[0104] In some cases, the UE may continue to report in this manner until a valid DL subframe is again detected. For example, the UE may rely on the eIMTA configuration in order to determine whether collision exists for CSI measurements and whether a valid DL subframe exists. As shown in the subsequent frame 1604, the eIMTA configuration may change subframes 3 and 8 back to DL subframes (changing back to TDD configuration No. 2, for example). Consequently, the UE can once again report a valid and current measurement.

[0105] It should be understood that the specific order or hierarchy of steps in the disclosed processes is an illustration of exemplary approaches. Based on design preferences, it should be understood that the specific order or hierarchy of steps in processes can be rearranged. Furthermore, some steps can be combined or omitted. The attached method claims present elements of the various steps in a sample order, and are not intended to be limited to the specific order or hierarchy presented.

[0106] Furthermore, the term “or” is intended to mean an inclusive “or” and not an exclusive “or”. That is, unless otherwise specified or clear from the context, the phrase, for example, “X uses A or B” is intended to mean any of the natural inclusive permutations. That is, for example, the allocation “X uses A or B” is satisfied by any of the following occurrences: X uses A; X uses B; or to a singular form. THE LOCUTION REFERRING TO “at least one of”, a list of items refers to any combination of these items, including single elements. As an example, “at least one of: a, b, or c” is intended to cover: a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination of these items that includes a multiple of the same element (such as, e.g. aa, bb, cc, aa-b, etc.)

[0107] The previous description is presented to allow anyone skilled in the art to put into practice the various aspects described herein. Various modifications in these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown here, but must be given the broad scope compatible with language claims, in which reference to an element in the singular is not intended to mean “one and only one”, unless specifically so stated, but instead “one or more”. Unless specifically stated otherwise, the term “some” refers to one or more. All structural and functional equivalents of elements of the various aspects written throughout this disclosure that are known or will become known to those skilled in the art are expressly incorporated herein by way of reference and are intended to be encompassed by the claims. Furthermore, nothing disclosed herein is intended to be dedicated to the public, regardless of whether or not such disclosure is explicitly mentioned in the claims. No claim element should be interpreted as a device plus function, unless the element is expressly mentioned using the phrase “device for”.

[0108] The various method operations described above can be performed by any suitable device capable of performing the corresponding functions. The device may include multiple hardware components and/or multiple hardware and/or software components and/or modules, which include, but are not limited to, a circuit, an application-specific integrated circuit (ASIC), or a processor.

[0109] For example, the device for receiving may comprise a receiver (the receiver 654RX, for example) or an antenna 652 of the user equipment 650 shown in Figure 6. The device for detecting and the device for prioritizing may comprise a system of processing, which may include one or more processors, such as the RX656 processor and/or the controller/processor 659 of user equipment 650. The reporting device may comprise a transmitter (the 654TX transmitter, for example) and/or an antenna 652 of user equipment 650.

Claims (12)

1. Method for wireless communications by a user equipment, UE, (102) in a Long Term Evolution, LTE, communication system, comprising: receiving (1302) signaling from a first uplink/downlink subframe configuration downward, UL/DL, time division duplexing, TDD, for communication with a base station, BS (106); receiving (1304) signaling at least one channel state information reporting configuration, CSI, which indicates at least two sets of subframes, wherein each set of subframes is associated with an interference measurement resource configuration, IMR; detecting (1306) a collision of CSI reports for the at least two sets of subframes in an uplink subframe; prioritizing (1308) a set of subframes from the at least two sets of subframes for CSI reporting in the uplink subframe; and reporting (1310) CSI in the uplink subframe based on prioritization, the method comprising: receiving a dynamically signaled indication that indicates a second UL/DL TDD subframe configuration; determining that the second UL/DL TDD subframe configuration reconfigures a downlink reference subframe to report CSI as an uplink subframe; change CSI reporting in response to determining that the second UL/DL TDD subframe configuration reconfigures the downlink reference subframe to report CSI as an uplink subframe, wherein the change comprises at least one of sending a report measurement with a value that is at least one of: previous or out of range; or issue a CSI report. 2. Method, according to claim 1, characterized by the fact that the at least two sets of subframes are associated with the same CSI process. 3. The method of claim 1, wherein a set of subframes with a lower set subframe set index among the colliding sets of subframes in the uplink subframe receives a higher priority. 4. Method according to claim 1, characterized by the fact that the CSI reporting configuration comprises one or more CSI processes for one or more component carriers, and the prioritization of the CSI reporting is based, in addition, at least one of a CSI report type, a CSI process index, or a component carrier index. 5. The method of claim 1, wherein the CSI report is a type of periodic CSI report. 6. The method of claim 1, wherein the first UL/DL subframe configuration is signaled via a system information block, SIB. 7. The method of claim 1, wherein the interference measurement features corresponding to at least two IMRs are not subject to a restriction that the at least two IMRs are limited to periodically occurring subframes. 8. Method according to claim 7, characterized by the fact that: the first UL/DL subframe configuration is signaled through a system information block, SIB; at least one of a first IMR and a second IMR in the at least two IMRs is only within DL subframes according to the first UL/DL subframe configuration; and at least one of the first IMR and the second IMR in the at least two IMRs is not subject to the restriction on DL subframes that were not DL subframes in the first UL/DL subframe configuration. 9. Method according to claim 8, characterized by the fact that the at least one of the first IMR and the second IMR, in the at least two IMRs that are only within the DL subframes, according to the first configuration of UL/DL subframe, is associated with the lowest subframe set index. 10. An apparatus for Long Term Evolution, LTE, wireless communication comprising: means for receiving (1302) signaling from a first uplink/downlink, UL/DL, subframe configuration for communication with a base station, BS (106); means for receiving (1304) signaling of at least one channel state information reporting configuration, CSI, which indicates at least two sets of subframes, wherein each set of subframes is associated with an interference measurement resource configuration, IMR; means for detecting (1306) a CSI reporting collision for the at least two sets of subframes in an uplink subframe; means for prioritizing (1308) a set of subframes of the at least two sets of subframes for reporting CSI in the uplink subframe; and means for reporting (1310) CSI in the uplink subframe based on prioritization; the apparatus comprising: means for receiving a dynamically signaled indication indicating a second UL/DL TDD subframe configuration; means for determining that the second UL/DL TDD subframe configuration reconfigures a downlink reference subframe to report CSI as an uplink subframe; means for changing the reporting of CSI in response to determining that the second UL/DL TDD subframe configuration reconfigures the downlink reference subframe to report CSI as an uplink subframe, wherein the change comprises at least one of send a measurement report with a value that is at least one of: previous or out of range; or issue a CSI report. 11. Apparatus according to claim 10, characterized by the fact that the at least two sets of subframes are associated with the same CSI process. 12. Computer-readable memory, characterized by the fact that it has instructions stored therein that, when executed, cause the computer to perform the method as defined in any one of claims 1 to 9.