WO2017099831A1

WO2017099831A1 - Control signaling in multiple beam operation

Info

Publication number: WO2017099831A1
Application number: PCT/US2016/024497
Authority: WO
Inventors: Yushu Zhang; Yuan Zhu; Huaning Niu; Gang Xiong; Wenting CHANG
Original assignee: Intel IP Corporation
Priority date: 2015-12-08
Filing date: 2016-03-28
Publication date: 2017-06-15
Also published as: TW201722097A; TWI767589B; TWI721029B; TW202135483A

Abstract

Techniques for generating control signaling for multiple beam transmissions are discussed. One example apparatus comprises a processor configured to: generate one or more downlink control information (DCI) messages, wherein each of the one or more DCI messages is associated with a distinct transmit beam of a multiple beam transmission to a user equipment (UE), wherein the multiple beam transmission comprises N_b transmit beams, wherein N_b is at least 2; assign each of the one or more DCI messages to an associated search space of one or more search spaces; and output the one or more DCI messages for subsequent transmission via transmitter circuitry during a common subframe, wherein the processor is configured to output each of the one or more DCI messages for subsequent transmission via a distinct transmit beam of the N_b transmit beams.

Description

CONTROL SIGNALING IN MULTIPLE BEAM OPERATION

REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Application No.

62/264,749 filed December 8, 2015, entitled "CONTROL SIGNALING IN DUAL BEAM OPERATION", the contents of which are herein incorporated by reference in their entirety.

FIELD

[0002] The present disclosure relates to wireless technology, and more specifically to techniques for communicating control signaling for multiple beam transmissions.

BACKGROUND

[0003] In massive Multiple Input and Multiple Output (MIMO) systems, the Evolved NodeB (eNB) can transmit the downlink control and data with analog beamforming. In such a scenario, a user equipment (UE) can have N_ap Receiving (Rx) antenna panels and be able to receive beams from one or more Transmission Points (TPs).

BRIEF DESCRIPTION OF THE DRAWINGS

[0004] FIG. 1 is a block diagram illustrating an example user equipment (UE) useable in connection with various aspects described herein.

[0005] FIG. 2 is a diagram illustrating an example intra-TP (transmission point) multiple (dual, in the example shown) beam transmission scenario wherein a serving TP can transmit control signaling according to various aspects described herein.

[0006] FIG. 3 is a diagram illustrating an example inter-TP (transmission point) multiple (dual, in the example shown) beam transmission scenario wherein the serving TP and/or assistant TP can transmit control signaling according to various aspects described herein.

[0007] FIG. 4 is a block diagram illustrating a system that facilitates generation and communication of downlink control signaling for a multiple beam transmission from a base station according to various aspects described herein.

[0008] FIG. 5 is a block diagram illustrating a system that facilitates reception of downlink control messages and generation of uplink control messages associated with a multiple beam transmission received at a user equipment (UE) according to various aspects described herein.

[0009] FIG. 6 is a diagram illustrating an example configuration of search spaces for a dual-beam operating mode according to various aspects described herein.

[0010] FIG. 7 is a diagram illustrating an example of HARQ process indication for independent HARQ operation in a dual-beam scenario according to various aspects discussed herein.

[0011] FIG. 8 is a diagram illustrating an example dual-beam scenario for HARQ indication based on a beam to HARQ process swap flag according to various aspects discussed herein.

[0012] FIG. 9 is a diagram illustrating an example dual-beam scenario of HARQ process indication for a common search space according to various aspects discussed herein.

[0013] FIG. 10 is a flow diagram illustrating an example method that facilitates generation of downlink control information for a multiple beam transmission comprising transmit beams from a base station according to various aspects described herein.

[0014] FIG. 11 is a flow diagram illustrating an example method that facilitates reception of downlink control information associated with a multiple beam transmission to a UE according to various aspects described herein.

DETAILED DESCRIPTION

[0015] The present disclosure will now be described with reference to the attached drawing figures, wherein like reference numerals are used to refer to like elements throughout, and wherein the illustrated structures and devices are not necessarily drawn to scale. As utilized herein, terms "component," "system," "interface," and the like are intended to refer to a computer-related entity, hardware, software (e.g., in execution), and/or firmware. For example, a component can be a processor (e.g., a microprocessor, a controller, or other processing device), a process running on a processor, a controller, an object, an executable, a program, a storage device, a computer, a tablet PC and/or a user equipment (e.g., mobile phone, etc.) with a processing device. By way of illustration, an application running on a server and the server can also be a component. One or more components can reside within a process, and a component can be localized on one computer and/or distributed between two or more computers. A set of elements or a set of other components can be described herein, in which the term "set" can be interpreted as "one or more."

[0016] Further, these components can execute from various computer readable storage media having various data structures stored thereon such as with a module, for example. The components can communicate via local and/or remote processes such as in accordance with a signal having one or more data packets (e.g., data from one component interacting with another component in a local system, distributed system, and/or across a network, such as, the Internet, a local area network, a wide area network, or similar network with other systems via the signal).

[0017] As another example, a component can be an apparatus with specific functionality provided by mechanical parts operated by electric or electronic circuitry, in which the electric or electronic circuitry can be operated by a software application or a firmware application executed by one or more processors. The one or more processors can be internal or external to the apparatus and can execute at least a part of the software or firmware application. As yet another example, a component can be an apparatus that provides specific functionality through electronic components without mechanical parts; the electronic components can include one or more processors therein to execute software and/or firmware that confer(s), at least in part, the functionality of the electronic components.

[0018] Use of the word exemplary is intended to present concepts in a concrete fashion. As used in this application, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless specified otherwise, or clear from context, "X employs A or B" is intended to mean any of the natural inclusive permutations. That is, if X employs A; X employs B; or X employs both A and B, then "X employs A or B" is satisfied under any of the foregoing instances. In addition, the articles "a" and "an" as used in this application and the appended claims should generally be construed to mean "one or more" unless specified otherwise or clear from context to be directed to a singular form. Furthermore, to the extent that the terms "including", "includes", "having", "has", "with", or variants thereof are used in either the detailed description and the claims, such terms are intended to be inclusive in a manner similar to the term

"comprising."

[0019] As used herein, the term "circuitry" may refer to, be part of, or include an Application Specific Integrated Circuit (ASIC), an electronic circuit, a processor (shared, dedicated, or group), and/or memory (shared, dedicated, or group) that execute one or more software or firmware programs, a combinational logic circuit, and/or other suitable hardware components that provide the described functionality. In some embodiments, the circuitry may be implemented in, or functions associated with the circuitry may be implemented by, one or more software or firmware modules. In some embodiments, circuitry may include logic, at least partially operable in hardware.

[0020] Embodiments described herein may be implemented into a system using any suitably configured hardware and/or software. FIG. 1 illustrates, for one embodiment, example components of a User Equipment (UE) device 100. In some embodiments, the UE device 100 may include application circuitry 102, baseband circuitry 104, Radio Frequency (RF) circuitry 106, front-end module (FEM) circuitry 108 and one or more antennas 1 10, coupled together at least as shown.

[0021] The application circuitry 102 may include one or more application processors. For example, the application circuitry 102 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The processor(s) may include any combination of general-purpose processors and dedicated processors (e.g., graphics processors, application processors, etc.). The processors may be coupled with and/or may include memory/storage and may be configured to execute instructions stored in the memory/storage to enable various applications and/or operating systems to run on the system.

[0022] The baseband circuitry 104 may include circuitry such as, but not limited to, one or more single-core or multi-core processors. The baseband circuitry 104 may include one or more baseband processors and/or control logic to process baseband signals received from a receive signal path of the RF circuitry 106 and to generate baseband signals for a transmit signal path of the RF circuitry 106. Baseband processing circuity 104 may interface with the application circuitry 102 for generation and processing of the baseband signals and for controlling operations of the RF circuitry 106. For example, in some embodiments, the baseband circuitry 104 may include a second generation (2G) baseband processor 104a, third generation (3G) baseband processor 104b, fourth generation (4G) baseband processor 104c, and/or other baseband processor(s) 104d for other existing generations, generations in development or to be developed in the future (e.g., fifth generation (5G), 6G, etc.). The baseband circuitry 104 (e.g., one or more of baseband processors 104a-d) may handle various radio control functions that enable communication with one or more radio networks via the RF circuitry 106. The radio control functions may include, but are not limited to, signal modulation/demodulation, encoding/decoding, radio frequency shifting, etc. In some embodiments, modulation/demodulation circuitry of the baseband circuitry 104 may include Fast-Fourier Transform (FFT), precoding, and/or constellation

mapping/demapping functionality. In some embodiments, encoding/decoding circuitry of the baseband circuitry 104 may include convolution, tail-biting convolution, turbo, Viterbi, and/or Low Density Parity Check (LDPC) encoder/decoder functionality.

Embodiments of modulation/demodulation and encoder/decoder functionality are not limited to these examples and may include other suitable functionality in other embodiments.

[0023] In some embodiments, the baseband circuitry 104 may include elements of a protocol stack such as, for example, elements of an evolved universal terrestrial radio access network (EUTRAN) protocol including, for example, physical (PHY), media access control (MAC), radio link control (RLC), packet data convergence protocol (PDCP), and/or radio resource control (RRC) elements. A central processing unit (CPU) 104e of the baseband circuitry 104 may be configured to run elements of the protocol stack for signaling of the PHY, MAC, RLC, PDCP and/or RRC layers. In some embodiments, the baseband circuitry may include one or more audio digital signal processor(s) (DSP) 104f. The audio DSP(s) 104f may be include elements for compression/decompression and echo cancellation and may include other suitable processing elements in other embodiments. Components of the baseband circuitry may be suitably combined in a single chip, a single chipset, or disposed on a same circuit board in some embodiments. In some embodiments, some or all of the constituent components of the baseband circuitry 104 and the application circuitry 102 may be implemented together such as, for example, on a system on a chip (SOC).

[0024] In some embodiments, the baseband circuitry 104 may provide for communication compatible with one or more radio technologies. For example, in some embodiments, the baseband circuitry 104 may support communication with an evolved universal terrestrial radio access network (EUTRAN) and/or other wireless metropolitan area networks (WMAN), a wireless local area network (WLAN), a wireless personal area network (WPAN). Embodiments in which the baseband circuitry 104 is configured to support radio communications of more than one wireless protocol may be referred to as multi-mode baseband circuitry.

[0025] RF circuitry 106 may enable communication with wireless networks using modulated electromagnetic radiation through a non-solid medium. In various embodiments, the RF circuitry 106 may include switches, filters, amplifiers, etc. to facilitate the communication with the wireless network. RF circuitry 106 may include a receive signal path which may include circuitry to down-convert RF signals received from the FEM circuitry 108 and provide baseband signals to the baseband circuitry 104. RF circuitry 106 may also include a transmit signal path which may include circuitry to up-convert baseband signals provided by the baseband circuitry 1 04 and provide RF output signals to the FEM circuitry 108 for transmission.

[0026] In some embodiments, the RF circuitry 106 may include a receive signal path and a transmit signal path. The receive signal path of the RF circuitry 106 may include mixer circuitry 1 06a, amplifier circuitry 106b and filter circuitry 106c. The transmit signal path of the RF circuitry 106 may include filter circuitry 106c and mixer circuitry 106a. RF circuitry 106 may also include synthesizer circuitry 106d for synthesizing a frequency for use by the mixer circuitry 106a of the receive signal path and the transmit signal path. In some embodiments, the mixer circuitry 106a of the receive signal path may be configured to down-convert RF signals received from the FEM circuitry 108 based on the synthesized frequency provided by synthesizer circuitry 106d. The amplifier circuitry 106b may be configured to amplify the down-converted signals and the filter circuitry 106c may be a low-pass filter (LPF) or band-pass filter (BPF) configured to remove unwanted signals from the down-converted signals to generate output baseband signals. Output baseband signals may be provided to the baseband circuitry 104 for further processing. In some embodiments, the output baseband signals may be zero- frequency baseband signals, although this is not a requirement. In some embodiments, mixer circuitry 1 06a of the receive signal path may comprise passive mixers, although the scope of the embodiments is not limited in this respect.

[0027] In some embodiments, the mixer circuitry 106a of the transmit signal path may be configured to up-convert input baseband signals based on the synthesized frequency provided by the synthesizer circuitry 106d to generate RF output signals for the FEM circuitry 108. The baseband signals may be provided by the baseband circuitry 104 and may be filtered by filter circuitry 1 06c. The filter circuitry 1 06c may include a low-pass filter (LPF), although the scope of the embodiments is not limited in this respect.

[0028] In some embodiments, the mixer circuitry 106a of the receive signal path and the mixer circuitry 106a of the transmit signal path may include two or more mixers and may be arranged for quadrature downconversion and/or upconversion respectively. In some embodiments, the mixer circuitry 106a of the receive signal path and the mixer circuitry 106a of the transmit signal path may include two or more mixers and may be arranged for image rejection (e.g., Hartley image rejection). In some embodiments, the mixer circuitry 1 06a of the receive signal path and the mixer circuitry 106a may be arranged for direct downconversion and/or direct upconversion, respectively. In some embodiments, the mixer circuitry 106a of the receive signal path and the mixer circuitry 106a of the transmit signal path may be configured for super-heterodyne operation.

[0029] In some embodiments, the output baseband signals and the input baseband signals may be analog baseband signals, although the scope of the embodiments is not limited in this respect. In some alternate embodiments, the output baseband signals and the input baseband signals may be digital baseband signals. In these alternate embodiments, the RF circuitry 106 may include analog-to-digital converter (ADC) and digital-to-analog converter (DAC) circuitry and the baseband circuitry 104 may include a digital baseband interface to communicate with the RF circuitry 106.

[0030] In some dual-mode embodiments, a separate radio IC circuitry may be provided for processing signals for each spectrum, although the scope of the

embodiments is not limited in this respect.

[0031] In some embodiments, the synthesizer circuitry 106d may be a fractional-N synthesizer or a fractional N/N+1 synthesizer, although the scope of the embodiments is not limited in this respect as other types of frequency synthesizers may be suitable. For example, synthesizer circuitry 106d may be a delta-sigma synthesizer, a frequency multiplier, or a synthesizer comprising a phase-locked loop with a frequency divider.

[0032] The synthesizer circuitry 106d may be configured to synthesize an output frequency for use by the mixer circuitry 106a of the RF circuitry 1 06 based on a frequency input and a divider control input. In some embodiments, the synthesizer circuitry 106d may be a fractional N/N+1 synthesizer.

[0033] In some embodiments, frequency input may be provided by a voltage controlled oscillator (VCO), although that is not a requirement. Divider control input may be provided by either the baseband circuitry 104 or the applications processor 102 depending on the desired output frequency. In some embodiments, a divider control input (e.g., N) may be determined from a look-up table based on a channel indicated by the applications processor 1 02.

[0034] Synthesizer circuitry 1 06d of the RF circuitry 106 may include a divider, a delay-locked loop (DLL), a multiplexer and a phase accumulator. In some embodiments, the divider may be a dual modulus divider (DMD) and the phase accumulator may be a digital phase accumulator (DPA). In some embodiments, the DMD may be configured to divide the input signal by either N or N+1 (e.g., based on a carry out) to provide a fractional division ratio. In some example embodiments, the DLL may include a set of cascaded, tunable, delay elements, a phase detector, a charge pump and a D-type flip- flop. In these embodiments, the delay elements may be configured to break a VCO period up into Nd equal packets of phase, where Nd is the number of delay elements in the delay line. In this way, the DLL provides negative feedback to help ensure that the total delay through the delay line is one VCO cycle.

[0035] In some embodiments, synthesizer circuitry 1 06d may be configured to generate a carrier frequency as the output frequency, while in other embodiments, the output frequency may be a multiple of the carrier frequency (e.g., twice the carrier frequency, four times the carrier frequency) and used in conjunction with quadrature generator and divider circuitry to generate multiple signals at the carrier frequency with multiple different phases with respect to each other. In some embodiments, the output frequency may be a LO frequency (fLO). In some embodiments, the RF circuitry 106 may include an IQ/polar converter.

[0036] FEM circuitry 108 may include a receive signal path which may include circuitry configured to operate on RF signals received from one or more antennas 1 10, amplify the received signals and provide the amplified versions of the received signals to the RF circuitry 106 for further processing. FEM circuitry 108 may also include a transmit signal path which may include circuitry configured to amplify signals for transmission provided by the RF circuitry 106 for transmission by one or more of the one or more antennas 1 1 0.

[0037] In some embodiments, the FEM circuitry 108 may include a TX/RX switch to switch between transmit mode and receive mode operation. The FEM circuitry may include a receive signal path and a transmit signal path. The receive signal path of the FEM circuitry may include a low-noise amplifier (LNA) to amplify received RF signals and provide the amplified received RF signals as an output (e.g., to the RF circuitry 106). The transmit signal path of the FEM circuitry 108 may include a power amplifier (PA) to amplify input RF signals (e.g., provided by RF circuitry 106), and one or more filters to generate RF signals for subsequent transmission (e.g., by one or more of the one or more antennas 1 1 0. [0038] In some embodiments, the UE device 100 may include additional elements such as, for example, memory/storage, display, camera, sensor, and/or input/output (I/O) interface.

[0039] Additionally, although the above example discussion of device 100 is in the context of a UE device, in various aspects, a similar device can be employed in connection with a base station (BS) such as an Evolved NodeB (eNB).

[0040] Referring to FIG. 2, illustrated is a diagram showing an example intra-TP (transmission point) multiple (dual, in the example shown) beam transmission scenario wherein a serving TP can transmit control signaling according to various aspects described herein. In the example scenario of FIG. 2, each receive (Rx) antenna panel of the UE (user equipment) can have different target Transmit (Tx) beams from a single TP, the Serving TP in FIG. 2. Referring to FIG. 3, illustrated is a diagram showing an example inter-TP (transmission point) multiple (dual, in the example shown) beam transmission scenario wherein the serving TP and/or assistant TP can transmit control signaling according to various aspects described herein. In the example scenario shown in FIG. 3, the two beams come from different TPs, and the TPs can be connected with an ideal backhaul or a non-ideal backhaul. It is important for a control signaling design to address these and other multiple beam transmission scenarios, which are

unaddressed by conventional LTE (Long Term Evolution) systems.

[0041] In various aspects, techniques for control beam signaling for multiple beam transmissions are discussed that can be employed in any multiple beam transmission scenario, such as intra-TP multiple beam transmissions, and inter-TP multiple beam transmissions with either ideal backhaul or non-ideal backhaul. In various embodiments, techniques are discussed herein for generating and/or communicating (1 ) downlink control signaling (e.g., DCI (downlink control information) messages) for xPDSCH (5G (fifth generation) physical downlink shared channel) and/or (2) UCI (uplink control information) feedback for multiple beam transmissions.

[0042] Referring to FIG. 4, illustrated is a block diagram of a system 400 that facilitates generation and communication of downlink control signaling for a multiple beam transmission from a base station according to various aspects described herein. System 400 can include a processor 410 (e.g., a baseband processor such as one of the baseband processors discussed in connection with FIG. 1 ), transmitter circuitry 420, and memory 430 (which can comprise any of a variety of storage mediums and can store instructions and/or data associated with one or more of processor 410, or transmitter circuitry 420). In various aspects, system 400 can be included within an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (Evolved Node B, eNodeB, or eNB) or other base station in a wireless communications network. In some aspects, the processor 410, the transmitter circuitry 420 and the memory 430 can be included in a single device, while in other aspects, they can be included in different devices, such as part of a distributed architecture. As described in greater detail below, system 400 can facilitate scheduling downlink assignments and/or uplink grants for one or more UEs in connection with a multiple beam transmission.

[0043] Processor 410 can generate one or more downlink control information (DCI) messages for a user equipment. Each of the DCI messages can be associated with a distinct transmit beams of a multiple beam (e.g., comprising N_b beams, where N_b is an integer greater than 1 ) transmission to the UE, such as each being associated with a different transmit beams of one or more transmit beams via which an eNB employing system 400 is communicating with the UE. In aspects where each of the N_b transmit beams originates from a single TP (e.g., a TP of that eNB), the multiple beam transmission is an intra-TP transmission, and processor 410 can generate N_b DCI messages, one for each of the N_b transmit beams. On the other hand, if at least two of the N_b transmit beams originate from distinct TPs, the multiple beam transmission is an inter-TP transmission, and processor 410 can generate less than N_b DCI messages.

[0044] Processor 410 can assign each of the DCI messages to a search space associated with that DCI message of one or more search spaces. In some aspects, the one or more search spaces can comprise a single common search space, and each of the DCI messages can be assigned to the single common search space. In such aspects, each of the DCI messages can comprise a beam indicator that indicates which transmit beam the DCI is associated with. In aspects employing a common search space, DCI messages can be assigned to distinct CCEs (control channel elements) in some aspects, while in other aspects, some or all of the DCI messages can be assigned to one or more common CCE indices that they share with other DCI messages.

[0045] In other aspects, the one or more search spaces can comprise N_b search spaces, which can be consecutive in various embodiments (e.g., such that the starting CCE of a search space of a next transmit beam can be determined from the search space of a previous transmit beam, .etc.). In these aspects, each of the N_b search spaces can be associated with a distinct transmit beam of the Nb transmit beams, and processor 410 can assign each DCI message to the search space associated with the transmit beam with which that DCI message is associated.

[0046] Processor 410 can also output the one or more DCI messages for

transmission (e.g., via transmitter circuitry 420) during a common subframe, which can be a subframe during which DCI messages associated with each of the N_b transmit beams are transmitted.

[0047] In aspects, processor 410 can also generate and output one or more higher layer (e.g., RRC (radio resource control) or MAC (medium access control), etc.) messages associated with the multiple beam transmission, such as to add or remove one or more secondary transmit beams of the multiple beam transmission.

[0048] Depending on the embodiment, various characteristics of the DCI messages generated by processor 410 can vary.

[0049] In a first set of embodiments, each of the N_b transmit beams can be associated with a distinct HARQ (hybrid automatic repeat request) process, and independent HARQ operation. In such embodiments, each DCI message can comprise a HARQ process ID that indicates a HARQ process out of a total number of HARQ processes (e.g., N) associated with the distinct transmit beam associated with that DCI message. In various such aspects, the indicated HARQ process can be identifiable based on the combination of the indicated HARQ process ID and which transmit beam that DCI message is associated with.

[0050] In a second set of embodiments, the corresponding HARQ process can be indicated solely by the HARQ process ID of the DCI message, indicating a HARQ process out of a larger, shared number of HARQ processes. For example, the total number of HARQ processes can be N_bxN, where N is the number of processes for single beam operation, and can be indicated via N_bxM bits, where M is a number of bits employed for indicating a HARQ process ID in single beam operation.

[0051] This second set of embodiments can facilitate xPDSCH retransmission via a different beam from an original transmission, which can provide diversity gain. For example, in some aspects, one of the DCI messages generated by processor 41 0 can be a DCI message associated with a retransmission of a transmission previously sent via a different transmit beam than the transmit beam associated with that DCI message. In situations in which a retransmission occurs, the DCI associated with the

retransmission can comprise a HARQ process swap indicator that can indicate the HARQ process associated with the retransmission. The HARQ process swap indicator can comprise 1 bit (e.g., a flag) for dual beam transmission, and in general can comprise [log₂ N_b] bits, where [ 1 is the ceiling function.

[0052] Referring to FIG. 5, illustrated is a block diagram of a system 500 that facilitates reception of downlink control messages and generation of uplink control messages associated with a multiple beam transmission received at a user equipment (UE) according to various aspects described herein. System 500 can include receiver circuitry 51 0, a processor 520 (e.g., a baseband processor such as one of the baseband processors discussed in connection with FIG. 1 ), transmitter circuitry 530, and a memory 540 (which can comprise any of a variety of storage mediums and can store instructions and/or data associated with one or more of receiver circuitry 510, processor 520, or transmitter circuitry 530). In various aspects, system 500 can be included within a user equipment (UE). As described in greater detail below, system 500 can facilitate reception of and recovery of one or more downlink control channel messages from one or more search spaces associated with a multiple beam transmission.

[0053] Receiver circuitry 510 can receive a multiple beam transmission over N_b transmit beams from one or more TPs (e.g., a single TP for intra-TP scenarios, and more than one TP for inter-TP scenarios), and can provide the multiple beam

transmission to processor 520.

[0054] Processor 520 can receive the multiple beam transmission from receiver circuitry 51 0, and can recover N_b distinct DCI messages from one or more search spaces, each of which is associated with a distinct transmit beam of the N_b transmit beams. Depending on the embodiment, the DCI messages can be recovered from a common search space, or from N_b consecutive search spaces, and the content of the DCI messages can vary in different embodiments.

[0055] Processor 520 can also generate one or more uplink control information (UCI) messages, and output the one or more UCI messages for subsequent transmission to at least one of the TPs. The one or more UCI messages can comprise some or all of the following information associated with the N_b transmit beams: BRS-RP (beam reference signal received power), CSI (channel state information), HARQ-ACK (HARQ- Acknowledgement) feedback, etc.

[0056] In some aspects, the one or more UCI messages can be a single UCI message comprising feedback information associated with each of the N_b transmit beams. In other aspects, the one or more UCI messages can be N_b UCI messages, each associated with a distinct transmit beam of the N_b transmit beams. [0057] Additionally, the TP or TPs that the UCI messages are output for subsequent transmission to can vary, depending on the embodiment. In some embodiments where each UCI comprises feedback information associated with a single transmit beam (or with one or more transmit beams from a common TP), each UCI message can be output for subsequent transmission to the TP from which that transmit beam or transmit beams were received. In other embodiments, each of the one or more UCI messages can be output for subsequent transmission to a single TP. That single TP can either be a TP from which a primary beam of the N_b beams was received, or it can be a TP as indicated via configuration received via higher layer signaling (e.g., RRC, etc.).

[0058] To provide specific examples of the techniques discussed herein, example embodiments and techniques are discussed below in the context of a dual beam transmission. However, it is to be appreciated that these embodiments and techniques can be extended to other numbers of transmit beams (e.g., N_b > 2).

[0059] In the dual-beam (or N_b-beam) operation mode, a UE can assume that it needs to receive the downlink signals from two (or N_b) transmit (Tx) beams. The Tx beam from the serving TP can be referred to as a primary Tx beam, and the Tx beam from the (one or more) assistant TP(s) can be referred to as secondary Tx beam(s).

[0060] For the intra-TP multiple beam operation case, the primary Tx beam can be the Tx beam with the strongest BRS-RP as measured from one or more antenna panels of the UE, and the secondary Tx beam can be the Tx beam with the strongest BRS-RP as measured from another antenna panel, or a next strongest from one or more antenna panels when the primary Tx beam is the strongest from all antenna panels, etc.

[0061] In various aspects, addition or removal of the secondary Tx beam(s) can be indicated via higher layer signaling, such as via a MAC control element, RRC signaling, etc. The higher layer signaling can indicate the Tx beam to add or remove via a BRS index of the beam, which can be reported explicitly by a UE with the BRS-RP for the secondary Tx beam.

[0062] For downlink (DL) control signaling, DCI can be used to carry downlink assignment(s) and/or uplink grant(s). In aspects, one DCI message can be used to carry the information for one beam. Thus, in dual-beam mode, the UE can assume that two DCI are available to be detected in one subframe (and in N_b-beam mode, N_b DCI are available to be detected).

[0063] In a first set of aspects, when decoding the xPDCCH (5G physical downlink control channel), the UE can have an additional search space for each of the secondary Tx beam(s). The search space for the primary Tx beam and the secondary Tx beam(s) can be consecutive, wherein the CCE index for both (or all N_b) search spaces can be consecutive. In these aspects, the starting CCE index for the (first) secondary Tx beam can be the consecutive CCE after the last CCE in the primary Tx beam given the largest search space size in all possible aggregation levels (and for embodiments with N_b > 2, the starting CCE for each additional secondary Tx beam can similarly follow that for the previous secondary Tx beam).

[0064] As an example of this set of aspects, if the search space is defined as in clause 9.1 .1 of 3GPP (third generation partnership project) TS (technical specification) 36.213, where the possible aggregation levels can be {1 , 2, 4, 8} and their

corresponding search space size can be {6, 12, 8, 16} CCEs, the search space for the secondary Tx beam can start from the CCE with index ε₁ + 17, where ε₁ indicates the first CCE index in the search space for the primary Tx beam (and similarly for a next secondary Tx beam, substituting ε₂ for e_t, where ε₂ indicates the first CCE index in the search space for the first secondary Tx beam, etc.). Referring to FIG. 6, illustrated is a diagram of an example configuration of search spaces for a dual-beam operating mode according to various aspects described herein.

[0065] In some embodiments, xPDSCH transmission on each beam can have independent HARQ operation. In these embodiments, a UE receiving a multi-beam transmission can find the corresponding HARQ process based on the HARQ process ID indicated by a DCI and the Tx beam of that DCI. The Tx beam of a DCI can be obtained by its search space location in embodiments wherein DCIs for distinct transmit beams are in distinct search spaces, and can be determined from the DCI when explicitly indicated via the DCI.

[0066] Referring to FIG. 7, illustrated is a diagram of an example of HARQ process indication for independent HARQ operation in a dual-beam scenario according to various aspects discussed herein. In the DCI in the primary search space in FIG. 7, the HARQ process ID can be x, and in the secondary search space DCI, the HARQ process ID can be y. The total number of HARQ process for one beam can be N.

[0067] In other embodiments, the corresponding HARQ process can be indicated solely by the HARQ process ID in the DCI. In some such embodiments, the total number of HARQ processes can be enlarged for the UE with the multi-beam

transmission. In one example, the total number of HARQ processes can be 2/V in a dual-beam embodiment (or

in an N_b beam multi-beam embodiment), and the number of bits for the HARQ process ID can be 2M, where M is the number of bits used for HARQ process ID for single beam operation. Compared with N HARQ processes per beam, this can facilitate xPDSCH retransmission on a different beam than the initial beam.

[0068] In some aspects, any of the Tx beams can be employed to re-transmit xPDSCH previously transmitted on another Tx beam, to obtain a diversity gain. For example, in a dual-beam embodiment, the primary Tx beam can be applied to retransmit xPDSCH initially transmitted via the secondary Tx beam, or vice versa. In such aspects, a beam to HARQ process swap flag (for dual-beam embodiments) or other HARQ process swap indicator can be added to the DCI to indicate which HARQ process the DCI is applied to. For dual-beam operation, the beam to HARQ process swap flag can comprise a 0 or 1 , where a 0 can indicate that the beam to HARQ process swap is disabled, and the value 1 can indicate that the beam to HARQ process swap is enabled.

[0069] Referring to FIG. 8, illustrated is a diagram of an example dual-beam scenario for HARQ indication based on a beam to HARQ process swap flag according to various aspects discussed herein. In the example scenario of FIG. 8, the HARQ process ID in the primary DCI is y, and the HARQ process ID in the secondary DCI is x.

[0070] In another set of embodiments, a single common search space can be applied for the UE for all of the transmit beams of the multiple beam transmission. In such aspects, a beam indicator (Bl) can be added to the DCI to indicate which beam that DCI is targeting. In one dual-beam example, the beam indicator could have 1 bit, where the first value can indicate the primary Tx beam and the second value can indicate the secondary Tx beam. In a N_b beam multiple beam environment, the Bl can comprise [log₂ N_b] bits, where [ 1 is the ceiling function. The N_b DCIs can be allocated to the same CCEs or different CCEs in the UE's search space. In aspects, the beam indicator can be enabled only when beam aggregation is used. The Bl can also be added in an uplink grant to indicate which beam the uplink transmission is allowed from. For a dual-beam example, it could indicate whether the uplink transmission is allowed from the primary Tx beam or the secondary Tx beam. Referring to FIG. 9, illustrated is an example dual-beam scenario of HARQ process indication for a common search space according to various aspects discussed herein.

[0071] Various aspects discussed herein can relate to techniques for communicating uplink control information (UCI) based on a multiple beam transmission received at a UE. The UCI can be transmitted via xPUSCH (5G physical uplink shared channel), which can be indicated by an uplink grant. In one set of UCI embodiments, the UE can assume that the TP from which the uplink grant for the UCI was decoded is the target Receiving Point (RP) for the UCI. Thus, in that set of embodiments, the UE can complete the power control operation based on that assumption.

[0072] In another set of UCI embodiments, the UE can always send one UCI using the primary beam to one RP, independent of where the uplink grant for that UCI was decoded. Thus, the UE need not maintain multiple Tx power control factors and Timing Advances (TAs), and the transmitted UCI can contain either only UCI for a single RP, or joint UCI for more than one (e.g., all) RPs. In some aspects, the RP to receive the UCI can be pre-defined to be the TP sending the primary Tx, while in other aspects the RP can be indicated via higher layer signaling.

[0073] If only one UCI is allowed to report in a subframe and the UCI resource collisions between the primary UCI and one or more secondary UCIs happen, the UE can either send the primary UCI only, or can transmit both (or multiple, depending on the embodiment) UCI together, in the order from the primary UCI to the secondary UCI(s).

[0074] In embodiments wherein a UE transmits a joint UCI, the joint UCI can comprise one or more of: up to W BRS-RPs, where W can be defined by the system; channel state information (CSI) measured from CSI-RS (CSI reference signals) in the primary Tx beam; HARQ-ACK for the primary Tx beam HARQ processes; CSI measured from CSI-RS in the secondary Tx beam(s); or HARQ-ACK for the secondary Tx beam processes.

[0075] In other embodiments, each UCI can contain the information for a beam r from which the uplink grant was received. The UCI can comprise one or more of: up to W BRS-RPs, where W can be defined by the system; channel state information (CSI) measured from CSI-RS (CSI reference signals) in beam r, or HARQ-ACK for beam r HARQ processes.

[0076] The BRS-RP ca be measured from all of the N_b Tx beams and only the highest W BRS-RPs can be reported. The CSI and HARQ-ACK in the UCI can be beam specific.

[0077] In various aspects, techniques and features discussed in connection with dual-beam embodiments can be extended to multiple beam operation with N_b beams. In various aspects, the search space for multiple beams can be consecutive, or can be a common search space. Instead of a beam to HARQ process swap flag, a [log₂ N_b] bit HARQ process swap indicated can be applied in the DCI to indicate which HARQ processes that DCI applies to, where N_b denotes the number of Tx beams.

[0078] Referring to FIG. 10, illustrated is a flow diagram of a method 1000 that facilitates generation of downlink control information for a multiple beam transmission comprising transmit beams from a base station according to various aspects described herein. In some aspects, method 1000 can be performed at an eNB. In other aspects, a machine readable medium can store instructions associated with method 1000 that, when executed, can cause an eNB to perform the acts of method 1000.

[0079] At 1010, one or more DCI messages can be generated for a UE, with each of the DCI messages associated with an uplink grant or a downlink assignment to the UE. The generated DCI messages can each be associated with a distinct transmit beam of one or more transmit beams from a N_b beam multiple beam transmission to the UE. Depending on the embodiment, the content of the DCI messages can vary, as described elsewhere herein (for example, in some embodiments, it can comprise one or more of a beam indicator or a HARQ process swap indicator, or neither, etc.).

[0080] At 1020, the one or more transmit beams can be transmitted to the UE as part of a multiple beam transmission, with each of the one or more transmit beams comprising the associated DCI message. Each of the one or more DCI messages can be transmitted via one or more search spaces associated with the UE (e.g., a single common search space, or a distinct search space of N_b consecutive search spaces). In some aspects, each of the DCI messages can be allocated to a distinct CCE, or in other aspects, one or more DCI messages can be allocated to a common CCE with at least one other DCI message (e.g., either one of the DCI messages generated at 101 0, or a DCI message associated with a distinct transmit beam of the N_b transmit beams).

[0081] At 1030, one or more UCI messages can be received from the UE based on at least one of the N_b transmit beams. In some aspects, the one or more UCI messages can comprise a distinct UCI message for each of the one or more DCI messages (e.g., comprising BRS-RPs, and HARQ-ACK and CSI-RS for the transmit beam associated with that DCI message). In other aspects, at least one of the UCI messages received can comprise feedback information (e.g., HARQ-ACK, CSI-RS, etc.) associated with at least one transmit beam other than the one or more transmit beams. [0082] At 1040, at least one of the N_b transmit beams can be added or removed from the multiple beam transmission, such as via higher layer signaling (e.g., RRC, MAC, etc.).

[0083] Referring to FIG. 11 , illustrated is a flow diagram of a method 1 100 that facilitates reception of downlink control information associated with a multiple beam transmission to a UE according to various aspects described herein. In some aspects, method 1 100 can be performed at a UE. In other aspects, a machine readable medium can store instructions associated with method 1 100 that, when executed, can cause a UE to perform the acts of method 1 100.

[0084] At 1 1 10, an N_b beam multiple beam transmission can be received from one or more TPs.

[0085] At 1 120, N_b distinct DCI messages can be recovered from one or more search spaces of the multiple beam transmission (e.g., a common search space, N_b consecutive search spaces, etc.).

[0086] At 1 130, one or more UCI messages can be generated based on the multiple beam transmission (e.g., a single joint UCI message, N_b distinct UCI messages, etc.).

[0087] At 1 140, the one or more UCI messages can be output for transmission to at least one of the TPs (e.g., a single TP such as the TP of a primary Tx beam or a TP configured via higher layer signaling, or with each UCI message being output for transmission to the TP that transmitted the Tx beam the UCI is based on.

[0088] Examples herein can include subject matter such as a method, means for performing acts or blocks of the method, at least one machine-readable medium including executable instructions that, when performed by a machine (e.g., a processor with memory, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or the like) cause the machine to perform acts of the method or of an apparatus or system for concurrent communication using multiple communication technologies according to embodiments and examples described.

[0089] Example 1 is an apparatus configured to be employed within an Evolved NodeB (eNB), comprising a processor configured to: generate one or more downlink control information (DCI) messages, wherein each of the one or more DCI messages is associated with a distinct transmit beam of a multiple beam transmission to a user equipment (UE), wherein the multiple beam transmission comprises N_b transmit beams, wherein N_b is at least 2; assign each of the one or more DCI messages to an associated search space of one or more search spaces; and output the one or more DCI messages for subsequent transmission via transmitter circuitry during a common subframe, wherein the processor is configured to output each of the one or more DCI messages for subsequent transmission via a distinct transmit beam of the N_b transmit beams.

[0090] Example 2 comprises the subject matter of any variation of example 1 , wherein the one or more search spaces comprise N_b consecutive search spaces, wherein each of the N_b transmit beams is associated with a distinct search space of the N_b consecutive search spaces, and wherein each of the one or more DCI messages is assigned to the distinct search space associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

[0091] Example 3 comprises the subject matter of any variation of any of examples 1 -2, wherein each of the N_b transmit beams is associated with a distinct set of hybrid automatic repeat request (HARQ) processes.

[0092] Example 4 comprises the subject matter of any variation of example 3, wherein each of the one or more DCI messages indicates, via a HARQ process identity (ID) of that DCI message, an indicated HARQ process out of a total number of N potential HARQ processes associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

[0093] Example 5 comprises the subject matter of any variation of example 4, wherein, for each of the one or more DCI messages, the indicated HARQ process is identifiable based on the HARQ process ID and the transmit beam via which that DCI message was output for subsequent transmission.

[0094] Example 6 comprises the subject matter of any variation of example 2, wherein a first DCI message of the one or more DCI messages is associated with a retransmission of a transmission previously sent via a transmit beam other than the distinct transmit beam via which the first DCI message was output for subsequent transmission.

[0095] Example 7 comprises the subject matter of any variation of example 6, wherein the first DCI message comprises a HARQ process swap indicator that indicates a HARQ process associated with the retransmission, wherein the HARQ process swap indicator comprises [log₂ N_bj bits.

[0096] Example 8 comprises the subject matter of any variation of any of examples 1 -2, wherein the N_b transmit beams share a common set of hybrid automatic repeat request (HARQ) processes. [0097] Example 9 comprises the subject matter of any variation of example 8, wherein the common set of HARQ processes comprises N_bxN HARQ processes, wherein each of the one or more DCI messages is configured to indicate one of the N_bxN HARQ processes via an N_bxM bit HARQ process identity (ID), wherein M is a number of bits of a HARQ process ID associated with single beam operation.

[0098] Example 10 comprises the subject matter of any variation of example 1 , wherein the one or more search spaces comprise a single common search space.

[0099] Example 1 1 comprises the subject matter of any variation of any of examples 2-5, wherein a first DCI message of the one or more DCI messages is associated with a retransmission of a transmission previously sent via a transmit beam other than the distinct transmit beam via which the first DCI message was output for subsequent transmission.

[00100] Example 12 comprises the subject matter of any variation of example 1 , wherein each of the N_b transmit beams is associated with a distinct set of hybrid automatic repeat request (HARQ) processes.

[00101 ] Example 13 comprises the subject matter of any variation of example 1 , wherein the N_b transmit beams share a common set of hybrid automatic repeat request (HARQ) processes.

[00102] Example 14 is a machine readable medium comprising instructions that, when executed, cause an Evolved NodeB (eNB) to: generate one or more downlink control information (DCI) messages associated with a user equipment (UE), wherein each of the one or more DCI messages is associated with one of an uplink grant to the UE or a downlink assignment to the UE; transmit, to the UE, one or more transmit beams of a multiple beam transmission comprising N_b transmit beams, wherein N_b is at least 2, wherein each of the one or more transmit beams comprises a distinct DCI message of the one or more DCI messages, and wherein each of the one or more DCI messages is transmitted via one or more search spaces associated with the UE; and receive one or more uplink control information (UCI) messages from the UE.

[00103] Example 15 comprises the subject matter of any variation of example 14, wherein the one or more search spaces comprise a single search space.

[00104] Example 16 comprises the subject matter of any variation of example 15, wherein each of the one or more DCI messages comprise a beam indicator (Bl) that indicates that the transmit beam of the N_b transmit beams that comprises that DCI message. [00105] Example 17 comprises the subject matter of any variation of example 14, wherein each of the one or more DCI messages is allocated to a distinct control channel element (CCE).

[00106] Example 18 comprises the subject matter of any variation of example 14, wherein at least one of the one or more DCI messages is allocated to a common control channel element (CCE) with at least one other DCI message transmitted via one of the N_b transmit beams.

[00107] Example 19 comprises the subject matter of any variation of example 14, wherein the one or more UCI messages comprise a distinct UCI message for each of the one or more transmit beams, wherein each of the distinct UCI messages comprise hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with that transmit beam.

[00108] Example 20 comprises the subject matter of any variation of example 14, wherein at least one of the one or more UCI messages comprises hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with a distinct transmit beam from the one or more transmit beams.

[00109] Example 21 comprises the subject matter of any variation of example 14, wherein the one or more search spaces comprise N_b consecutive search spaces.

[00110] Example 22 comprises the subject matter of any variation of any of examples 14-21 , wherein the instructions, when executed, further cause the eNB to configure the UE to add or remove at least one transmit beam of the multiple beam transmission via higher layer signaling.

[00111 ] Example 23 comprises the subject matter of any variation of any of examples 14-21 , wherein the higher layer signaling comprises one of medium access control (MAC) signaling or radio resource control (RRC) signaling.

[00112] Example 24 comprises the subject matter of any variation of any of examples 14-1 6, wherein each of the one or more DCI messages is allocated to a distinct control channel element (CCE).

[00113] Example 25 comprises the subject matter of any variation of any of examples 14-1 6, wherein at least one of the one or more DCI messages is allocated to a common control channel element (CCE) with at least one other DCI message transmitted via one of the N_b transmit beams.

[00114] Example 26 comprises the subject matter of any variation of example 14, wherein the instructions, when executed, further cause the eNB to configure the UE to add or remove at least one transmit beam of the multiple beam transmission via higher layer signaling.

[00115] Example 27 comprises the subject matter of any variation of example 14, wherein the higher layer signaling comprises one of medium access control (MAC) signaling or radio resource control (RRC) signaling.

[00116] Example 28 is an apparatus configured to be employed within a User

Equipment (UE), comprising a processor configured to: receive, from coupled receiver circuitry, a multiple beam transmission comprising N_b transmit beams from one or more transmission points (TPs), wherein N_b is at least 2; recover N_b distinct downlink control information (DCI) messages of each of the N_b transmit beams from one or more search spaces; generate one or more uplink control information (UCI) messages; and output the one or more UCI messages for subsequent transmission to at least one of the one or more TPs.

[00117] Example 29 comprises the subject matter of any variation of example 28, wherein the one or more TPs are a single TP.

[00118] Example 30 comprises the subject matter of any variation of example 28, wherein the one or more TPs comprise at least two distinct TPs.

[00119] Example 31 comprises the subject matter of any variation of any of examples

28-30, wherein the one or more UCI messages comprise N_b distinct UCI message, wherein each of the N_b distinct UCI messages comprises feedback information associated with a distinct transmit beam of the N_b transmit beams.

[00120] Example 32 comprises the subject matter of any variation of example 31 , wherein the processor is configured to output each of the N_b UCI messages to the TP of the one or more TPs from which the transmit beam associated with that UCI message was received.

[00121 ] Example 33 comprises the subject matter of any variation of any of examples 28-30, wherein the one or more UCI messages comprise a single UCI message, wherein the single UCI message comprises joint feedback information associated with each the N_b transmit beams.

[00122] Example 34 comprises the subject matter of any variation of any of examples 28-30, wherein the processor is configured to output the one or more UCI messages to a single TP. [00123] Example 35 comprises the subject matter of any variation of example 34, wherein the single TP is the TP from which a primary beam of the N_b transmit beams was received.

[00124] Example 36 comprises the subject matter of any variation of example 34, wherein the processor is configured to receive, via the receiver circuitry, higher layer signaling that indicates the single TP from among the one or more TPs.

[00125] Example 37 comprises the subject matter of any variation of example 28, wherein the one or more UCI messages comprise N_b distinct UCI message, wherein each of the N_b distinct UCI messages comprises feedback information associated with a distinct transmit beam of the N_b transmit beams.

[00126] Example 38 comprises the subject matter of any variation of example 37, wherein the processor is configured to output each of the N_b UCI messages to the TP of the one or more TPs from which the transmit beam associated with that UCI message was received.

[00127] Example 39 comprises the subject matter of any variation of example 28, wherein the one or more UCI messages comprise a single UCI message, wherein the single UCI message comprises joint feedback information associated with each the N_b transmit beams.

[00128] Example 40 comprises the subject matter of any variation of example 28, wherein the processor is configured to output the one or more UCI messages to a single TP.

[00129] Example 41 comprises the subject matter of any variation of example 40, wherein the single TP is the TP from which a primary beam of the N_b transmit beams was received.

[00130] Example 42 comprises the subject matter of any variation of example 40, wherein the processor is configured to receive, via the receiver circuitry, higher layer signaling that indicates the single TP from among the one or more TPs.

[00131 ] Example 43 is a method configured to be employed within an Evolved NodeB (eNB), comprising: generating one or more downlink control information (DCI) messages associated with a user equipment (UE), wherein each of the one or more DCI messages is associated with one of an uplink grant to the UE or a downlink assignment to the UE; transmitting, to the UE, one or more transmit beams of a multiple beam transmission comprising N_b transmit beams, wherein N_b is at least 2, wherein each of the one or more transmit beams comprises a distinct DCI message of the one or more DCI messages, and wherein each of the one or more DCI messages is transmitted via one or more search spaces associated with the UE; and receiving one or more uplink control information (UCI) messages from the UE.

[00132] Example 44 comprises the subject matter of any variation of example 43, wherein the one or more search spaces comprise a single search space.

[00133] Example 45 comprises the subject matter of any variation of example 44, wherein each of the one or more DCI messages comprise a beam indicator (Bl) that indicates that the transmit beam of the N_b transmit beams that comprises that DCI message.

[00134] Example 46 comprises the subject matter of any variation of example 43, wherein each of the one or more DCI messages is allocated to a distinct control channel element (CCE).

[00135] Example 47 comprises the subject matter of any variation of example 43, wherein at least one of the one or more DCI messages is allocated to a common control channel element (CCE) with at least one other DCI message transmitted via one of the N_b transmit beams.

[00136] Example 48 comprises the subject matter of any variation of example 43, wherein the one or more UCI messages comprise a distinct UCI message for each of the one or more transmit beams, wherein each of the distinct UCI messages comprise hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with that transmit beam.

[00137] Example 49 comprises the subject matter of any variation of example 43, wherein at least one of the one or more UCI messages comprises hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with a distinct transmit beam from the one or more transmit beams.

[00138] Example 50 comprises the subject matter of any variation of example 43, wherein the one or more search spaces comprise N_b consecutive search spaces.

[00139] Example 51 comprises the subject matter of any variation of any of examples 43-50, wherein the instructions, when executed, further cause the eNB to configure the UE to add or remove at least one transmit beam of the multiple beam transmission via higher layer signaling.

[00140] Example 52 comprises the subject matter of any variation of any of examples 43-50, wherein the higher layer signaling comprises one of medium access control (MAC) signaling or radio resource control (RRC) signaling. [00141 ] Example 53 is a machine-readable medium comprising instruction that, when executed, cause an Evolved NodeB (eNB) to perform the method of any of examples 43-52.

[00142] Example 54 is an apparatus configured to be employed within an Evolved NodeB (eNB), comprising means for processing and means for transmitting. The means for processing is configured to generate one or more downlink control information (DCI) messages, wherein each of the one or more DCI messages is associated with a distinct transmit beam of a multiple beam transmission to a user equipment (UE), wherein the multiple beam transmission comprises N_b transmit beams, wherein N_b is at least 2; and assign each of the one or more DCI messages to an associated search space of one or more search spaces. The means for transmitting is configured to transmit the one or more DCI messages during a common subframe, wherein the means for transmitting is configured to transmit each of the one or more DCI messages via a distinct transmit beam of the N_b transmit beams.

[00143] Example 55 comprises the subject matter of any variation of example 54, wherein the one or more search spaces comprise N_b consecutive search spaces, wherein each of the N_b transmit beams is associated with a distinct search space of the N_b consecutive search spaces, and wherein each of the one or more DCI messages is assigned to the distinct search space associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

[00144] Example 56 comprises the subject matter of any variation of any of examples 54-55, wherein each of the N_b transmit beams is associated with a distinct set of hybrid automatic repeat request (HARQ) processes.

[00145] Example 57 comprises the subject matter of any variation of example 56, wherein each of the one or more DCI messages indicates, via a HARQ process identity (ID) of that DCI message, an indicated HARQ process out of a total number of N potential HARQ processes associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

[00146] Example 58 comprises the subject matter of any variation of example 57, wherein, for each of the one or more DCI messages, the indicated HARQ process is identifiable based on the HARQ process ID and the transmit beam via which that DCI message was output for subsequent transmission.

[00147] Example 59 comprises the subject matter of any variation of example 55, wherein a first DCI message of the one or more DCI messages is associated with a retransmission of a transmission previously sent via a transmit beam other than the distinct transmit beam via which the first DCI message was output for subsequent transmission.

[00148] Example 60 comprises the subject matter of any variation of example 59, wherein the first DCI message comprises a HARQ process swap indicator that indicates a HARQ process associated with the retransmission, wherein the HARQ process swap indicator comprises [log₂ N_b] bits.

[00149] Example 61 comprises the subject matter of any variation of any of examples 54-55, wherein the N_b transmit beams share a common set of hybrid automatic repeat request (HARQ) processes.

[00150] Example 62 comprises the subject matter of any variation of example 61 , wherein the common set of HARQ processes comprises N_bxN HARQ processes, wherein each of the one or more DCI messages is configured to indicate one of the N_bxN HARQ processes via an N_bx bit HARQ process identity (ID), wherein M is a number of bits of a HARQ process ID associated with single beam operation.

[00151 ] Example 63 comprises the subject matter of any variation of example 54, wherein the one or more search spaces comprise a single common search space.

[00152] Example 64 is an apparatus configured to be employed within a User Equipment (UE), comprising means for receiving, means for processing, and means for transmitting. The means for receiving is configured to receive a multiple beam transmission comprising N_b transmit beams from one or more transmission points (TPs), wherein N_b is at least 2. The means for processing is configured to recover N_b distinct downlink control information (DCI) messages of each of the N_b transmit beams from one or more search spaces; and generate one or more uplink control information (UCI) messages. The means for transmitting is configured to transmit the one or more UCI messages to at least one of the one or more TPs.

[00153] Example 65 comprises the subject matter of any variation of any of examples 1 -13, wherein the processor is a baseband processor.

[00154] The above description of illustrated embodiments of the subject disclosure, including what is described in the Abstract, is not intended to be exhaustive or to limit the disclosed embodiments to the precise forms disclosed. While specific embodiments and examples are described herein for illustrative purposes, various modifications are possible that are considered within the scope of such embodiments and examples, as those skilled in the relevant art can recognize. [00155] In this regard, while the disclosed subject matter has been described in connection with various embodiments and corresponding Figures, where applicable, it is to be understood that other similar embodiments can be used or modifications and additions can be made to the described embodiments for performing the same, similar, alternative, or substitute function of the disclosed subject matter without deviating therefrom. Therefore, the disclosed subject matter should not be limited to any single embodiment described herein, but rather should be construed in breadth and scope in accordance with the appended claims below.

[00156] In particular regard to the various functions performed by the above described components or structures (assemblies, devices, circuits, systems, etc.), the terms (including a reference to a "means") used to describe such components are intended to correspond, unless otherwise indicated, to any component or structure which performs the specified function of the described component (e.g., that is functionally equivalent), even though not structurally equivalent to the disclosed structure which performs the function in the herein illustrated exemplary implementations. In addition, while a particular feature may have been disclosed with respect to only one of several implementations, such feature may be combined with one or more other features of the other implementations as may be desired and advantageous for any given or particular application.

Claims

CLAIMS What is claimed is:

1 . An apparatus configured to be employed within an Evolved NodeB (eNB), comprising:

a processor configured to:

generate one or more downlink control information (DCI) messages, wherein each of the one or more DCI messages is associated with a distinct transmit beam of a multiple beam transmission to a user equipment (UE), wherein the multiple beam transmission comprises N_b transmit beams, wherein N_b is at least 2;

assign each of the one or more DCI messages to an associated search space of one or more search spaces; and

output the one or more DCI messages for subsequent transmission via transmitter circuitry during a common subframe, wherein the processor is configured to output each of the one or more DCI messages for subsequent transmission via a distinct transmit beam of the N_b transmit beams.

2. The apparatus of claim 1 , wherein the one or more search spaces comprise N_b consecutive search spaces, wherein each of the N_b transmit beams is associated with a distinct search space of the N_b consecutive search spaces, and wherein each of the one or more DCI messages is assigned to the distinct search space associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

3. The apparatus of any of claims 1 -2, wherein each of the N_b transmit beams is associated with a distinct set of hybrid automatic repeat request (HARQ) processes.

4. The apparatus of claim 3, wherein each of the one or more DCI messages indicates, via a HARQ process identity (ID) of that DCI message, an indicated HARQ process out of a total number of N potential HARQ processes associated with the distinct transmit beam via which that DCI message was output for subsequent transmission.

5. The apparatus of claim 4, wherein, for each of the one or more DCI messages, the indicated HARQ process is identifiable based on the HARQ process ID and the transmit beam via which that DCI message was output for subsequent transmission.

6. The apparatus of claim 2, wherein a first DCI message of the one or more DCI messages is associated with a retransmission of a transmission previously sent via a transmit beam other than the distinct transmit beam via which the first DCI message was output for subsequent transmission.

7. The apparatus of claim 6, wherein the first DCI message comprises a HARQ process swap indicator that indicates a HARQ process associated with the

retransmission, wherein the HARQ process swap indicator comprises \log₂ N_b] bits.

8. The apparatus of any of claims 1 -2, wherein the N_b transmit beams share a common set of hybrid automatic repeat request (HARQ) processes.

9. The apparatus of claim 8, wherein the common set of HARQ processes comprises N_bxN HARQ processes, wherein each of the one or more DCI messages is configured to indicate one of the N_bxN HARQ processes via an N_bxM bit HARQ process identity (ID), wherein M is a number of bits of a HARQ process ID associated with single beam operation.

10. The apparatus of claim 1 , wherein the one or more search spaces comprise a single common search space.

1 1 . A machine readable medium comprising instructions that, when executed, cause an Evolved NodeB (eNB) to:

generate one or more downlink control information (DCI) messages associated with a user equipment (UE), wherein each of the one or more DCI messages is associated with one of an uplink grant to the UE or a downlink assignment to the UE; transmit, to the UE, one or more transmit beams of a multiple beam transmission comprising N_b transmit beams, wherein N_b is at least 2, wherein each of the one or more transmit beams comprises a distinct DCI message of the one or more DCI messages, and wherein each of the one or more DCI messages is transmitted via one or more search spaces associated with the UE; and

receive one or more uplink control information (UCI) messages from the UE.

12. The machine readable medium of claim 1 1 , wherein the one or more search spaces comprise a single search space.

13. The machine readable medium of claim 12, wherein each of the one or more DCI messages comprise a beam indicator (Bl) that indicates that the transmit beam of the N_b transmit beams that comprises that DCI message.

14. The machine readable medium of claim 1 1 , wherein each of the one or more DCI messages is allocated to a distinct control channel element (CCE).

15. The machine readable medium of claim 1 1 , wherein at least one of the one or more DCI messages is allocated to a common control channel element (CCE) with at least one other DCI message transmitted via one of the N_b transmit beams.

16. The machine readable medium of claim 1 1 , wherein the one or more UCI messages comprise a distinct UCI message for each of the one or more transmit beams, wherein each of the distinct UCI messages comprise hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with that transmit beam.

17. The machine readable medium of claim 1 1 , wherein at least one of the one or more UCI messages comprises hybrid automatic repeat request (HARQ) feedback and channel state information (CSI) associated with a distinct transmit beam from the one or more transmit beams.

18. The machine readable medium of claim 1 1 , wherein the one or more search spaces comprise N_b consecutive search spaces.

19. The machine readable medium of any of claims 1 1 -18, wherein the instructions, when executed, further cause the eNB to configure the UE to add or remove at least one transmit beam of the multiple beam transmission via higher layer signaling.

20. The machine readable medium of any of claims 1 1 -18, wherein the higher layer signaling comprises one of medium access control (MAC) signaling or radio resource control (RRC) signaling.

21 . An apparatus configured to be employed within a User Equipment (UE), comprising:

a processor configured to:

receive, from coupled receiver circuitry, a multiple beam transmission comprising N_b transmit beams from one or more transmission points (TPs), wherein N_b is at least 2;

recover N_b distinct downlink control information (DCI) messages of each of the N_b transmit beams from one or more search spaces;

generate one or more uplink control information (UCI) messages; and output the one or more UCI messages for subsequent transmission to at least one of the one or more TPs.

22. The apparatus of claim 21 , wherein the one or more TPs are a single TP.

23. The apparatus of claim 21 , wherein the one or more TPs comprise at least two distinct TPs.

24. The apparatus of any of claims 21 -23, wherein the one or more UCI messages comprise N_b distinct UCI message, wherein each of the N_b distinct UCI messages comprises feedback information associated with a distinct transmit beam of the N_b transmit beams.

25. The apparatus of claim 24, wherein the processor is configured to output each of the N_b UCI messages to the TP of the one or more TPs from which the transmit beam associated with that UCI message was received.

26. The apparatus of any of claims 21 -23, wherein the one or more UCI messages comprise a single UCI message, wherein the single UCI message comprises joint feedback information associated with each the N_b transmit beams.

27. The apparatus of any of claims 21 -23, wherein the processor is configured to output the one or more UCI messages to a single TP.

28. The apparatus of claim 27, wherein the single TP is the TP from which a primary beam of the N_b transmit beams was received.

29. The apparatus of claim 27, wherein the processor is configured to receive, via the receiver circuitry, higher layer signaling that indicates the single TP from among the one or more TPs.