WO2020056783A1

WO2020056783A1 - Codeword mapping for dl multiplexing of embb and urllc with non-coherent joint transmission

Info

Publication number: WO2020056783A1
Application number: PCT/CN2018/107161
Authority: WO
Inventors: Qiaoyu Li; Yu Zhang; Chao Wei; Chenxi HAO; Hao Xu; Wanshi Chen
Original assignee: Qualcomm Incorporated
Priority date: 2018-09-22
Filing date: 2018-09-22
Publication date: 2020-03-26

Abstract

Certain aspects of the present disclosure provide techniques for mapping codewords, of a joint transmission from multiple transmitting entities to a user equipment, to resources subject to preemption.

Description

CODEWORD MAPPING FOR DL MULTIPLEXING OF EMBB AND URLLC WITH NON-COHERENT JOINT TRANSMISSION

INTRODUCTION

Field of the Disclosure

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for mapping codewords, of a joint transmission from multiple transmitting entities to a user equipment, to resources subject to preemption.

Description of Related Art

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts, etc. These wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc. ) . Examples of such multiple-access systems include 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) systems, LTE Advanced (LTE-A) systems, code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems, to name a few.

In some examples, a wireless multiple-access communication system may include a number of base stations (BSs) , which are each capable of simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs) . In an LTE or LTE-A network, a set of one or more base stations may define an eNodeB (eNB) . In other examples (e.g., in a next generation, a new radio (NR) , or 5G network) , a wireless multiple access communication system may include a number of distributed units (DUs) (e.g., edge units (EUs) , edge nodes (ENs) , radio heads (RHs) , smart radio heads (SRHs) , transmission reception points (TRPs) , etc. ) in communication with a number of central units (CUs) (e.g., central nodes (CNs) , access node controllers (ANCs) , etc. ) , where a set of one or more DUs, in communication with a CU, may define an access node (e.g., which may be referred to as a BS, 5G NB, next generation NodeB (gNB or gNodeB) , transmission reception point (TRP) , etc. ) . A BS or DU may communicate with a set of UEs on downlink channels (e.g., for transmissions from a BS or DU to a UE) and uplink channels (e.g., for transmissions from a UE to BS or DU) .

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. NR (e.g., new radio or 5G) is an example of an emerging telecommunication standard. NR is a set of enhancements to the LTE mobile standard promulgated by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using OFDMA with a cyclic prefix (CP) on the downlink (DL) and on the uplink (UL) . To these ends, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in NR and LTE technology. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.

BRIEF SUMMARY

The systems, methods, and devices of the disclosure each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this disclosure as expressed by the claims which follow, some features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled “Detailed Description” one will understand how the features of this disclosure provide advantages that include improved communications between access points and stations in a wireless network.

Certain aspects provide a method for wireless communication by a base station (BS) . The method generally includes determining a time domain resource mapping rule for transmitting a codeword of a scheduled joint data transmission of a first type from a group of transmitting entities to a user equipment (UE) , wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword and transmitting the codeword according to the determined time domain resource mapping rule.

Certain aspects provide a method for wireless communication by a user equipment (UE) . The method generally includes receiving codewords of a joint data transmission of a first type from a group of transmitting entities, determining a time domain resource mapping rule used by each of the transmitting entities for transmitting their respective codeword, wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword, decoding each codeword according to the time domain mapping rule applied by the corresponding transmitting entity, and combining decoding results for each codeword.

Aspects also include various apparatuses, means, and computer readable mediums having instructions for performing the operations described herein.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the appended drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects.

FIG. 1 is a block diagram conceptually illustrating an example telecommunications system, in accordance with certain aspects of the present disclosure.

FIG. 2 is a block diagram illustrating an example logical architecture of a distributed radio access network (RAN) , in accordance with certain aspects of the present disclosure.

FIG. 3 is a diagram illustrating an example physical architecture of a distributed RAN, in accordance with certain aspects of the present disclosure.

FIG. 4 is a block diagram conceptually illustrating a design of an example base station (BS) and user equipment (UE) , in accordance with certain aspects of the present disclosure.

FIG. 5 is a diagram showing examples for implementing a communication protocol stack, in accordance with certain aspects of the present disclosure.

FIG. 6 illustrates an example of a frame format for a new radio (NR) system, in accordance with certain aspects of the present disclosure.

FIG. 7 is an example of downlink preemption and the impact caused thereby.

FIG. 8 illustrates example operations for wireless communication by a network entity, in accordance with certain aspects of the present disclosure.

FIG. 9 illustrates example operations for wireless communication by a user equipment, in accordance with certain aspects of the present disclosure.

FIGs. 10-12 illustrate examples of time domain resource mapping, in accordance with certain aspects of the present disclosure.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized on other aspects without specific recitation.

DETAILED DESCRIPTION

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for mapping codewords, of a joint transmission from multiple transmitting entities to a user equipment, to resources subject to preemption.

In certain systems, such as NR (new radio or 5G) systems, a scheduled PDSCH may be preempted by another PDSCH transmission. For example, NR supports a variety of services including enhanced mobile broadband (eMBB) and ultra-reliable low-latency communications (URLLC) . An eMBB PDSCH may be preempted by a URLLC PDSCH. The base station (BS) provides a downlink preemption indicator (DLPI) to the user equipment (UE) , indicating the preempted resources, to improve decoding performance at the UE, for example.

As will be described in greater detail below, this preemption may cause a loss of codewords scheduled for transmission in symbols subject to preemption.

The following description provides examples, and is not limiting of the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to, or other than, the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects.

The techniques described herein may be used for various wireless communication technologies, such as LTE, CDMA, TDMA, FDMA, OFDMA, SC-FDMA and other networks. The terms “network” and “system” are often used interchangeably. A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA) , cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM) . An OFDMA network may implement a radio technology such as NR (e.g. 5G RA) , Evolved UTRA (E-UTRA) , Ultra Mobile Broadband (UMB) , IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash-OFDMA, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunication System (UMTS) .

New Radio (NR) is an emerging wireless communications technology under development in conjunction with the 5G Technology Forum (5GTF) . 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP) . cdma2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) . The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. For clarity, while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including NR technologies.

New radio (NR) access (e.g., 5G technology) may support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth (e.g., 80 MHz or beyond) , millimeter wave (mmW) targeting high carrier frequency (e.g., 25 GHz or beyond) , massive machine type communications MTC (mMTC) targeting non-backward compatible MTC techniques, and/or mission critical targeting ultra-reliable low-latency communications (URLLC) . These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTI) to meet respective quality of service (QoS) requirements. In addition, these services may co-exist in the same subframe.

Example Wireless Communications System

FIG. 1 illustrates an example wireless communication network 100 in which aspects of the present disclosure may be performed. For example, the wireless communication network 100 may be a New Radio (NR) or 5G network. The wireless communication network 100 may support enhanced mobile broadband (eMBB) and ultra-reliable low-latency communication (URLLC) services. A base station (BS) , such as a BS 110 in the wireless communication network 100 may schedule physical downlink shared channel (PDSCH) transmission to a user equipment (UE) , such as a UE 120 in the wireless communication network 100. The BS 110 may preempt the scheduled PDSCH with another PDSCH. For example, the BS 110 may schedule an eMBB PDSCH in a slot, then the BS 110 may transmit a URLLC PDSCH in one more symbols of the slot scheduled for the eMBB PDSCH, the URLCC PDSCH preempting the eMBB PDSCH. The BS 110 may send the UE 120 a downlink preemption indictor (DLPI) indicating the preempted resources. The BS 110 may ensure that the UE 120 can process the PDSCH taking into account the preempted resources. For example, the BS 110 determines a feedback timing indicator associated with the scheduled PDSCH. The BS 110 may determine the feedback timing indicator based on the number of slots between the scheduled PDSCH and the DLPI and on the minimum processing time associated with the UE. The BS 110 includes the feedback timing indicator in the downlink control information (DCI) scheduling the PDSCH. The UE 120 can determine when to process the PDSCH based on the feedback timing indicator.

As illustrated in FIG. 1, the wireless communication network 100 may include a number of base stations (BSs) 110 and other network entities. A BS may be a station that communicates with user equipments (UEs) . Each BS 110 may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a Node B (NB) and/or a NB subsystem serving this coverage area, depending on the context in which the term is used. In NR systems, the term “cell” and next generation NB (gNB or gNodeB) , NR BS, 5G NB, access point (AP) , or transmission reception point (TRP) may be interchangeable. In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some examples, the base stations may be interconnected to one another and/or to one or more other base stations or network nodes (not shown) in wireless communication network 100 through various types of backhaul interfaces, such as a direct physical connection, a wireless connection, a virtual network, or the like using any suitable transport network.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular radio access technology (RAT) and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, etc. A frequency may also be referred to as a carrier, a subcarrier, a frequency channel, a tone, a subband, etc. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or other types of cells. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG) , UEs for users in the home, etc. ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1, the

BSs

110a, 110b and 110c may be macro BSs for the

macro cells

102a, 102b and 102c, respectively. The BS 110x may be a pico BS for a pico cell 102x. The BSs 110y and 110z may be femto BSs for the

femto cells

102y and 102z, respectively. A BS may support one or multiple (e.g., three) cells.

Wireless communication network 100 may also include relay stations. A relay station is a station that receives a transmission of data and/or other information from an upstream station (e.g., a BS or a UE) and sends a transmission of the data and/or other information to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that relays transmissions for other UEs. In the example shown in FIG. 1, a relay station 110r may communicate with the BS 110a and a UE 120r in order to facilitate communication between the BS 110a and the UE 120r. A relay station may also be referred to as a relay BS, a relay, etc.

Wireless communication network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BS, pico BS, femto BS, relays, etc. These different types of BSs may have different transmit power levels, different coverage areas, and different impact on interference in the wireless communication network 100. For example, macro BS may have a high transmit power level (e.g., 20 Watts) whereas pico BS, femto BS, and relays may have a lower transmit power level (e.g., 1 Watt) .

Wireless communication network 100 may support synchronous or asynchronous operation. For synchronous operation, the BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timing, and transmissions from different BSs may not be aligned in time. The techniques described herein may be used for both synchronous and asynchronous operation.

A network controller 130 may couple to a set of BSs and provide coordination and control for these BSs. The network controller 130 may communicate with the BSs 110 via a backhaul. The BSs 110 may also communicate with one another (e.g., directly or indirectly) via wireless or wireline backhaul.

The UEs 120 (e.g., 120x, 120y, etc. ) may be dispersed throughout the wireless communication network 100, and each UE may be stationary or mobile. A UE may also be referred to as a mobile station, a terminal, an access terminal, a subscriber unit, a station, a Customer Premises Equipment (CPE) , a cellular phone, a smart phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, an appliance, a medical device or medical equipment, a biometric sensor/device, a wearable device such as a smart watch, smart clothing, smart glasses, a smart wrist band, smart jewelry (e.g., a smart ring, a smart bracelet, etc. ) , an entertainment device (e.g., a music device, a video device, a satellite radio, etc. ) , a vehicular component or sensor, a smart meter/sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium. Some UEs may be considered machine-type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., that may communicate with a BS, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

Certain wireless networks (e.g., LTE) utilize orthogonal frequency division multiplexing (OFDM) on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, etc. Each subcarrier may be modulated with data. In general, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may be dependent on the system bandwidth. For example, the spacing of the subcarriers may be 15 kHz and the minimum resource allocation (called a “resource block” (RB) ) may be 12 subcarriers (or 180 kHz) . Consequently, the nominal Fast Fourier Transfer (FFT) size may be equal to 128, 256, 512, 1024 or 2048 for system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz) , respectively. The system bandwidth may also be partitioned into subbands. For example, a subband may cover 1.08 MHz (i.e., 6 resource blocks) , and there may be 1, 2, 4, 8, or 16 subbands for system bandwidth of 1.25, 2.5, 5, 10 or 20 MHz, respectively.

While aspects of the examples described herein may be associated with LTE technologies, aspects of the present disclosure may be applicable with other wireless communications systems, such as NR. NR may utilize OFDM with a CP on the uplink and downlink and include support for half-duplex operation using TDD. Beamforming may be supported and beam direction may be dynamically configured. MIMO transmissions with precoding may also be supported. MIMO configurations in the DL may support up to 8 transmit antennas with multi-layer DL transmissions up to 8 streams and up to 2 streams per UE. Multi-layer transmissions with up to 2 streams per UE may be supported. Aggregation of multiple cells may be supported with up to 8 serving cells.

In some examples, access to the air interface may be scheduled, wherein a. A scheduling entity (e.g., a base station) allocates resources for communication among some or all devices and equipment within its service area or cell. The scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, subordinate entities utilize resources allocated by the scheduling entity. Base stations are not the only entities that may function as a scheduling entity. In some examples, a UE may function as a scheduling entity and may schedule resources for one or more subordinate entities (e.g., one or more other UEs) , and the other UEs may utilize the resources scheduled by the UE for wireless communication. In some examples, a UE may function as a scheduling entity in a peer-to-peer (P2P) network, and/or in a mesh network. In a mesh network example, UEs may communicate directly with one another in addition to communicating with a scheduling entity.

In FIG. 1, a solid line with double arrows indicates desired transmissions between a UE and a serving BS, which is a BS designated to serve the UE on the downlink and/or uplink. A finely dashed line with double arrows indicates interfering transmissions between a UE and a BS.

FIG. 2 illustrates an example logical architecture of a distributed Radio Access Network (RAN) 200, which may be implemented in the wireless communication network 100 illustrated in FIG. 1. A 5G access node 206 may include an ANC 202. ANC 202 may be a central unit (CU) of the distributed RAN 200. The backhaul interface to the Next Generation Core Network (NG-CN) 204 may terminate at ANC 202. The backhaul interface to neighboring next generation access Nodes (NG-ANs) 210 may terminate at ANC 202. ANC 202 may include one or more TRPs 208 (e.g., cells, BSs, gNBs, etc. ) .

The TRPs 208 may be a distributed unit (DU) . TRPs 208 may be connected to a single ANC (e.g., ANC 202) or more than one ANC (not illustrated) . For example, for RAN sharing, radio as a service (RaaS) , and service specific AND deployments, TRPs 208 may be connected to more than one ANC. TRPs 208 may each include one or more antenna ports. TRPs 208 may be configured to individually (e.g., dynamic selection) or jointly (e.g., joint transmission) serve traffic to a UE.

The logical architecture of distributed RAN 200 may support fronthauling solutions across different deployment types. For example, the logical architecture may be based on transmit network capabilities (e.g., bandwidth, latency, and/or jitter) .

The logical architecture of distributed RAN 200 may share features and/or components with LTE. For example, next generation access node (NG-AN) 210 may support dual connectivity with NR and may share a common fronthaul for LTE and NR.

The logical architecture of distributed RAN 200 may enable cooperation between and among TRPs 208, for example, within a TRP and/or across TRPs via ANC 202. An inter-TRP interface may not be used.

Logical functions may be dynamically distributed in the logical architecture of distributed RAN 200. As will be described in more detail with reference to FIG. 5, the Radio Resource Control (RRC) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, Medium Access Control (MAC) layer, and a Physical (PHY) layers may be adaptably placed at the DU (e.g., TRP 208) or CU (e.g., ANC 202) .

FIG. 3 illustrates an example physical architecture of a distributed RAN 300, according to aspects of the present disclosure. A centralized core network unit (C-CU) 302 may host core network functions. C-CU 302 may be centrally deployed. C-CU 302 functionality may be offloaded (e.g., to advanced wireless services (AWS) ) , in an effort to handle peak capacity.

A centralized RAN unit (C-RU) 304 may host one or more ANC functions. Optionally, the C-RU 304 may host core network functions locally. The C-RU 304 may have distributed deployment. The C-RU 304 may be close to the network edge.

A DU 306 may host one or more TRPs (Edge Node (EN) , an Edge Unit (EU) , a Radio Head (RH) , a Smart Radio Head (SRH) , or the like) . The DU may be located at edges of the network with radio frequency (RF) functionality.

FIG. 4 illustrates example components of BS 110 and UE 120 (as depicted in FIG. 1) , which may be used to implement aspects of the present disclosure. For example, antennas 452,

processors

466, 458, 464, and/or controller/processor 480 of the UE 120 and/or antennas 434,

processors

420, 460, 438, and/or controller/processor 440 of the BS 110 may be used to perform the various techniques and methods described herein for PDSCH processing in the presence of DLPI.

At the BS 110, a transmit processor 420 may receive data from a data source 412 and control information from a controller/processor 440. The control information may be for the physical broadcast channel (PBCH) , physical control format indicator channel (PCFICH) , physical hybrid ARQ indicator channel (PHICH) , physical downlink control channel (PDCCH) , group common PDCCH (GC PDCCH) , etc. The data may be for the physical downlink shared channel (PDSCH) , etc. The processor 420 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The processor 420 may also generate reference symbols, e.g., for the primary synchronization signal (PSS) , secondary synchronization signal (SSS) , and cell-specific reference signal (CRS) . A transmit (TX) multiple-input multiple-output (MIMO) processor 430 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 432a through 432t. Each modulator 432 may process a respective output symbol stream (e.g., for OFDM, etc. ) to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from modulators 432a through 432t may be transmitted via the antennas 434a through 434t, respectively.

At the UE 120, the antennas 452a through 452r may receive the downlink signals from the base station 110 and may provide received signals to the demodulators (DEMODs) in transceivers 454a through 454r, respectively. Each demodulator 454 may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator may further process the input samples (e.g., for OFDM, etc. ) to obtain received symbols. A MIMO detector 456 may obtain received symbols from all the demodulators 454a through 454r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 458 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 120 to a data sink 460, and provide decoded control information to a controller/processor 480.

On the uplink, at UE 120, a transmit processor 464 may receive and process data (e.g., for the physical uplink shared channel (PUSCH) ) from a data source 462 and control information (e.g., for the physical uplink control channel (PUCCH) from the controller/processor 480. The transmit processor 464 may also generate reference symbols for a reference signal (e.g., for the sounding reference signal (SRS) ) . The symbols from the transmit processor 464 may be precoded by a TX MIMO processor 466 if applicable, further processed by the demodulators in transceivers 454a through 454r (e.g., for SC-FDM, etc. ) , and transmitted to the base station 110. At the BS 110, the uplink signals from the UE 120 may be received by the antennas 434, processed by the modulators 432, detected by a MIMO detector 436 if applicable, and further processed by a receive processor 438 to obtain decoded data and control information sent by the UE 120. The receive processor 438 may provide the decoded data to a data sink 439 and the decoded control information to the controller/processor 440.

The controllers/

processors

440 and 480 may direct the operation at the BS 110 and the UE 120, respectively. The processor 440 and/or other processors and modules at the BS 110 may perform or direct the execution of processes for the techniques described herein. The

memories

442 and 482 may store data and program codes for BS 110 and UE 120, respectively. A scheduler 444 may schedule UEs for data transmission on the downlink and/or uplink.

FIG. 5 illustrates a diagram 500 showing examples for implementing a communications protocol stack, according to aspects of the present disclosure. The illustrated communications protocol stacks may be implemented by devices operating in a wireless communication system, such as a 5G system (e.g., a system that supports uplink-based mobility) . Diagram 500 illustrates a communications protocol stack including a RRC layer 510, a PDCP layer 515, a RLC layer 520, a MAC layer 525, and a PHY layer 530. In various examples, the layers of a protocol stack may be implemented as separate modules of software, portions of a processor or ASIC, portions of non-collocated devices connected by a communications link, or various combinations thereof. Collocated and non-collocated implementations may be used, for example, in a protocol stack for a network access device (e.g., ANs, CUs, and/or DUs) or a UE.

A first option 505-a shows a split implementation of a protocol stack, in which implementation of the protocol stack is split between a centralized network access device (e.g., an ANC 202 in FIG. 2) and distributed network access device (e.g., DU 208 in FIG. 2) . In the first option 505-a, an RRC layer 510 and a PDCP layer 515 may be implemented by the central unit, and an RLC layer 520, a MAC layer 525, and a PHY layer 530 may be implemented by the DU. In various examples the CU and the DU may be collocated or non-collocated. The first option 505-a may be useful in a macro cell, micro cell, or pico cell deployment.

A second option 505-b shows a unified implementation of a protocol stack, in which the protocol stack is implemented in a single network access device. In the second option, RRC layer 510, PDCP layer 515, RLC layer 520, MAC layer 525, and PHY layer 530 may each be implemented by the AN. The second option 505-b may be useful in, for example, a femto cell deployment.

Regardless of whether a network access device implements part or all of a protocol stack, a UE may implement an entire protocol stack as shown in 505-c (e.g., the RRC layer 510, the PDCP layer 515, the RLC layer 520, the MAC layer 525, and the PHY layer 530) .

In LTE, the basic transmission time interval (TTI) or packet duration is the 1 ms subframe. In NR, a subframe is still 1 ms, but the basic TTI is referred to as a slot. A subframe contains a variable number of slots (e.g., 1, 2, 4, 8, 16, …slots) depending on the subcarrier spacing. The NR RB is 12 consecutive frequency subcarriers. NR may support a base subcarrier spacing of 15 KHz and other subcarrier spacing may be defined with respect to the base subcarrier spacing, for example, 30 kHz, 60 kHz, 120 kHz, 240 kHz, etc. The symbol and slot lengths scale with the subcarrier spacing. The CP length also depends on the subcarrier spacing.

FIG. 6 is a diagram showing an example of a frame format 600 for NR. The transmission timeline for each of the downlink and uplink may be partitioned into units of radio frames. Each radio frame may have a predetermined duration (e.g., 10 ms) and may be partitioned into 10 subframes, each of 1 ms, with indices of 0 through 9. Each subframe may include a variable number of slots depending on the subcarrier spacing. Each slot may include a variable number of symbol periods (e.g., 14 symbols) depending on the subcarrier spacing. The symbol periods in each slot may be assigned indices. A mini-slot is a subslot structure (e.g., 2, 3, or 4 symbols) .

Each symbol in a slot may indicate a link direction (e.g., DL, UL, or flexible) for data transmission and the link direction for each subframe may be dynamically switched. The link directions may be based on the slot format. Each slot may include DL/UL data as well as DL/UL control information.

In NR, a synchronization signal (SS) block is transmitted. The SS block includes a PSS, a SSS, and a two symbol PBCH. The SS block can be transmitted in a fixed slot location, such as the symbols 0-3 as shown in FIG. 6. The PSS and SSS may be used by UEs for cell search and acquisition. The PSS may provide half-frame timing, the SS may provide the CP length and frame timing. The PSS and SSS may provide the cell identity. The PBCH carries some basic system information (SI) , such as downlink system bandwidth, timing information within radio frame, SS burst set periodicity, system frame number, etc. The SS blocks may be organized into SS bursts to support beam sweeping. Further system information such as, remaining minimum system information (RMSI) , system information blocks (SIBs) , other system information (OSI) can be transmitted on a PDSCH in certain subframes.

In some circumstances, two or more subordinate entities (e.g., UEs) may communicate with each other using sidelink signals. Real-world applications of such sidelink communications may include public safety, proximity services, UE-to-network relaying, vehicle-to-vehicle (V2V) communications, Internet of Everything (IoE) communications, IoT communications, mission-critical mesh, and/or various other suitable applications. Generally, a sidelink signal may refer to a signal communicated from one subordinate entity (e.g., UE1) to another subordinate entity (e.g., UE2) without relaying that communication through the scheduling entity (e.g., UE or BS) , even though the scheduling entity may be utilized for scheduling and/or control purposes. In some examples, the sidelink signals may be communicated using a licensed spectrum (unlike wireless local area networks, which typically use an unlicensed spectrum) .

A UE may operate in various radio resource configurations, including a configuration associated with transmitting pilots using a dedicated set of resources (e.g., a radio resource control (RRC) dedicated state, etc. ) or a configuration associated with transmitting pilots using a common set of resources (e.g., an RRC common state, etc. ) . When operating in the RRC dedicated state, the UE may select a dedicated set of resources for transmitting a pilot signal to a network. When operating in the RRC common state, the UE may select a common set of resources for transmitting a pilot signal to the network. In either case, a pilot signal transmitted by the UE may be received by one or more network access devices, such as an, or a DU, or portions thereof. Each receiving network access device may be configured to receive and measure pilot signals transmitted on the common set of resources, and also receive and measure pilot signals transmitted on dedicated sets of resources allocated to the UEs for which the network access device is a member of a monitoring set of network access devices for the UE. One or more of the receiving network access devices, or a CU to which receiving network access device (s) transmit the measurements of the pilot signals, may use the measurements to identify serving cells for the UEs, or to initiate a change of serving cell for one or more of the UEs.

Example Time Domain Codeword Mapping for NC-JT

Certain aspects of the present disclosure provide techniques for mapping codewords, of a joint transmission from multiple transmitting entities to a user equipment, to resources subject to preemption. The transmitting entities may be associated with a virtual cell ID or a demodulation reference signal (DMRS) port group ID and, in some cases, may be referred to herein as a transmitter receiver point (TRP) .

The mapping rules presented herein may help improve performance by helping avoid a total loss of codewords due to preemption, for example, by having different transmitting entities map codewords to different symbols.

In certain systems, such as NR (new radio or 5G) systems, a scheduled PDSCH may be preempted by another PDSCH transmission. For example, NR supports a variety of services including enhanced mobile broadband (eMBB) and ultra-reliable low-latency communications (URLLC) . An eMBB PDSCH may be preempted by a URLLC PDSCH, in a manner prioritizing URLLC traffic over eMBB traffic. Preemption, in this context, means that the entity transmitting eMBB data in PDSCH would stop its eMBB transmission on the symbols preempted by URLLC-and a UE receiving the PDSCH interprets the preemption indication in this manner, allowing it to consider this when decoding.

In current systems, for an eMBB UE, if URLLC transmits data on its scheduled DL, the preemption is indicated to this UE in the following Group-Common DCI (GC-DCI) , to be monitored by the UE using an RRC configured radio Network Temporary Identifier (RNTI) , which may be referred to as an interruption RNTI (int-RNTI) .

For a serving cell, the indication is provided as an {M, N} bit-map, representing M time-domain parts and N frequency-domain parts regarding the last GC-DCI periodicity. The bitmap is overall 14-bits, taking a single slot with 14 OFDM symbols.

In some cases, codeblock group (CBG) -Based Hybrid Automatic Repeat Request HARQ-ACK may be employed in multi-TRP non-coherent joint transmission (NC-JT) schemes. In these cases, a transport block (TB) consists of codeblocks (CBs) , where several CBs form a CBG. The number of CBs within a CBG is typically NW configured and acknowledgement/negative-acknowledgement (ACK/NACK) of transmissions is at the CBG level.

In diversity enhancement based (DEB) multi-TRP NC-JT schemes, multiple TRPs non-coherently transmit different codewords (CWs) , or different parts of a CW, or different/same redundancy version (RV) of a CW to the UE. The TRP-specific signals are respectively decoded and locally combined at the UE for diversity enhancement.

In a Multi-TRP scenario with DL URLLC &eMBB multiplexing, a certain symbol in the eMBB PDSCH may be interrupted by URLLC (from one or multiple TRPs) . For example, an eMBB UE, if URLLC transmits data (typically a mini-slot duration) on its scheduled PDSCH, the eMBB data on the associated symbols of PDSCH is therefore interrupted.

Unfortunately, such interruption may adversely impact the diversity enhancement.

This is illustrated by the example shown in FIG. 7, when both URLLC and eMBB traffic are present. The illustrated example shows 2-TRPs, each transmitting a different CW using a single layer to the UE. Preemption indication periodicity is 1-slot. In this example, the 6th symbol of the considered slot is interrupted by URLLC. As a result, in this example, both TRP-#0 and TRP-#1 stop transmitting eMBB in this symbol.

Considering the DEB-NC-JT scenario, if all TRPs are transmitting the same RV to an eMBB UE, if signals from all these TRPs are interrupted by URLLC for a certain symbol, as illustrated in FIG. 7, the redundancy made by using multiple TRPs does not provide any help in terms of diversity.

Aspects of the present disclosure, however, provide carefully designed codeword mapping rules that may help address this issue and maintain a level of diversity even in the event of interruption due to preemption.

FIG. 8 is a flow diagram showing example operations 800 for wireless communications by a network entity, in accordance with certain aspects of the present disclosure. The operations 800 may be performed by a transmitting entity, such as a BS 110 of FIG. 1 or TRP 208 of FIG. 2.

Operations 800 begin, at 802, by determining a time domain resource mapping rule for transmitting a codeword of a scheduled joint data transmission of a first type from a group of transmitting entities to a user equipment (UE) , wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword. At 804, the transmitting entity transmits the codeword according to the determined time domain resource mapping rule.

FIG. 9 is a flow diagram showing example operations 900 for wireless communications by a user equipment (UE) , in accordance with certain aspects of the present disclosure. Operations 900 may be performed, for example, by a UE such as a UE 120 of FIG. 1 to process transmission sent via NC-JT.

Operations 900 may begin, at 902, by receiving codewords of a joint data transmission of a first type from a group of transmitting entities. At 904, the UE determines a time domain resource mapping rule used by each of the transmitting entities for transmitting their respective codeword, wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword. At 906, the UE decodes each codeword according to the time domain mapping rule applied by the corresponding transmitting entity. At 908, the UE combines decoding results for each codeword.

Various solutions are provided to help maintain diversity and improve performance of NC-JT in the event of preemption. In some cases, the solutions vary based on the resource granularity or unit at which a mapping occurs. For example, a first solution (referred to herein as Solution-1) , may involve a CBG-level mapping.

The following solutions assume an NC-JT scheme involving N TRPs, where each one transmits the same RV of a CW consisting of M CBGs and each TRP maps the resource elements (REs) corresponding to CBGs, in a space-frequency-time order. Each TRP, however, may have a TRP-specific time domain mapping order.

For example, a first variation of CBG-level mapping may be referred to as a CW-Level Reversed Mapping. As the name implies, the mapping of one TRP may be a reverse order of the mapping of another TRP. For example, the TRP-specific time-domain mapping orders for the N TRPs may be as follows:

TRP-1: CBG-#1 → CBG-#2 → …→ CBG-# (M-1) → CBG-#M.

TRP-2: CBG-#M → CBG-# (M-1) → …→ CBG-#2 → CBG-#1.

TRP-3: The same as TRP- (3-k) .

…

TRP-N: The same as TRP- (N-k) .

The value of k can be 1 or 2, and can be indicated via DCI, RRC, or simply fixed. One advantage of this approach is that, assuming only a certain symbol is interrupted by URLLC, the polluted signals within the symbol of a certain TRP can be found, from another TRP’s signal according to the above mapping rules. Therefore diversity is still enhanced, even in the event of preemption.

The advantage of CW Level Reverse mapping is illustrated by the example shown in FIG. 10. The example assumes the same scenario as in the example illustrated in FIG. 7, with 2-TRPs (TRP-#1 and TRP-#2) each transmitting a different CW using a single layer to the UE. The CW includes 80 CBs and 4 CBGs, such that each CBG is consisted of 20 CBs. As illustrated, the TRP-specific mapping rules are:

TRP-#1: CBG-#1 → CBG-#2 → CBG→#3 → CBG-#4.

TRP-#2: CBG-#4 → CBG-#3 → CBG→#2 → CBG-#1.

As illustrated, URLLC interrupts the 6th symbol of both TRPs. However, some degree of diversity is maintained due to the different mapping rules employed by the TRPs. For example, as illustrated, for TRP-#1, the interrupted parts (from the 6th symbol) still exist in the 9th symbol of TRP-#2. Similarly, for TRP-#2, the interrupted parts (from the 6th symbol) still exist in the 9th symbol of TRP-#1.

There are limits to this approach, however. For example, if URLLC also interrupts the 9th symbol of both TRPs, the interrupted parts would no longer exist. Further, to combine decoding results from all TRPs, the UE would need to wait until each CBG is decoded for every TRP. Therefore, a longer delay may be encountered comparing to the case where each TRP maps CBG in the same order, where decoding can be carried out once a CB/CBG is received.

A second variation of CBG-level mapping may be referred to as a CW-Level shifted Mapping. As the name implies, the mapping of one TRP may be a shifted version of the mapping of another TRP. For example, the TRP-specific time-domain mapping orders for the N TRPs may be as follows:

TRP-1: CBG-#1 → CBG-#2 → …→ CBG-# (M-1) → CBG-#M.

TRP-2: CBG-#1+S → CBG-# (2+S) → …→ CBG-#M → CBG-#1 → …→ CBG-#S.

TRP-3: The same as TRP- (3-k) .

…

TRP-N: The same as TRP- (N-k) .

The value of S is a shift offset in terms of the CBG index, and can be configured via DCI, RRC, or simply fixed. Similarly, the value of k can be 1 or 2, and can be indicated via DCI, RRC, or simply fixed.

One advantage of this CW Level Shifted mapping relative to the CW Level Reverse mapping is that, if the number of CBGs is an odd number, the CBG in the middle would still be overlapped in time-domain using the CW Level Reverse mapping. Using the CW Level Shifted mapping, with proper configuration of the value of S, such problem can be avoided. As with the CW Level reverse mapping, however, to combine decoding results from all TRPs, the UE needs to wait until each CBG is decoded for every TRP.

A third variation of CBG-level mapping may be referred to as a Partitioned CW-Level Reversed Mapping. As the name implies, the M CBGs may be partitioned into groups, each having P CBGs. Within each partition, the mapping of one TRP (for the P CBGs in that partition) may be a reverse order of the mapping of another TRP. For example, the TRP-specific time-domain mapping orders for the N TRPs may be as follows:

TRP-1:

TRP-2:

TRP-3: The same as TRP- (3-k) .

…

TRP-N: The same as TRP- (N-k) .

The value of k can be 1 or 2, and can be indicated via DCI, RRC, or simply fixed. The value of P decides the CW partition level, which can also be configured via DCI, or RRC, or simply fixed. In general, the smaller the value of P is, the shorter the decoding delay. However, when P=1, this falls back to conventional mapping (per FIG. 7) . On the other hand, when the number of PRBs is large, if the value of P is chosen too small, some CBGs may be allocated to the same symbol even for different TRP, such that the pollution from URLLC may still not be entirely avoided.

The advantage of Partitioned CW-Level Reversed Mapping is illustrated by the example shown in FIG. 11. Again, this example assumes the same scenario as in the example illustrated in FIG. 7. In addition, the example assumes a partitions size P of 2. As illustrated, the TRP-specific mapping rules are:

TRP-1: CBG-#1 → CBG-#2 → CBG→#3 → CBG-#4.

TRP-2: CBG-#2 → CBG-#1 → CBG→#4 → CBG-#3

As illustrated, even though URLLC interrupts the 6th symbol of both TRPs, some degree of diversity is maintained due to the different mapping rules employed by the TRPs. For example, as illustrated, for TRP-#1, the interrupted parts (from the 6th symbol) still exist in the 3rd symbol of TRP-#2. Similarly, for TRP-#2, the interrupted parts (from the 6th symbol) still exist in the 3rd symbol of TRP-#1. Unfortunately, if URLLC also interrupts the 3rd symbol of both TRPs, the interrupted parts would no longer exist.

A fourth variation of CBG-level mapping may be referred to as a Partitioned CW-Level Shifted Mapping, which may be considered a combination of the second and third variations described above. As the name implies, the M CBGs may be partitioned into groups, each having P CBGs. Within each partition, the mapping of one TRP (for the P CBGs in that partition) may be a shifted version of the mapping of another TRP. For example, the TRP-specific time-domain mapping orders for the N TRPs may be as follows:

TRP-1:

TRP-2:

TRP-3: The same as TRP- (3-k) .

…

TRP-N: The same as TRP- (N-k) .

Again, the values of S, P, and k can be configured via DCI, RRC, or simply fixed. The advantages to this approach may be similar to the Partitioned CW-Level Reverse Mapping described above.

A fifth variation of CBG-level mapping may be referred to as an Interleaved Mapping. In this case, each TRP may have a mapping rule based on a different interleaver pattern designed to achieve a randomized order to the resource mapping. For example, the TRP-specific time-domain mapping orders for the N TRPs may be as follows:

TRP-1: CBG-#1 → CBG-#2 → …→ CBG-# (M-1) → CBG-#M.

TRP-2: a TRP-2 specific randomized order of CBGs (#1-#M) .

TRP-3: a TRP-3 specific randomized order of CBGs (#1-#M) .

…

TRP-N: a TRP-N specific randomized order of CBGs (#1-#M) .

The randomized order may be based on a demodulation reference signal (DMRS) port group index associated with a TRP applying the mapping rule and/or could be based on an ID associated with the UE, such as a radio Network Temporary Identifier (RNTI) . The randomized order can also be indicated to the UE via DCI or RRC signaling.

The advantage of Interleaved Mapping is illustrated by the example shown in FIG. 12. Again, this example assumes the same scenario as in the example illustrated in FIG. 7. As illustrated, the TRP-specific mapping rules are:

TRP-#1: CBG-#1 → CBG-#2 → CBG→#3 → CBG-#4.

TRP-#2: CBG-#3 → CBG-#1 → CBG→#2 → CBG-#4.

As with the previous examples, URLLC interrupts the 6th symbol of both TRPs. In this example, for TRP-#1, the interrupted parts still exist in the 9th symbol of TRP-#2. For TRP-2, however, the interrupted parts still exist in the 3rd symbol of TRP-1 (not the night) . Thus, due to the interleaving, if URLLC also interrupts the 3rd symbol of both TRPs, the interrupted parts regarding TRP-2 on the 6th symbol may not exist, but the parts regarding TRP-1 on the 6th symbol still exists, while the interrupted part on the 3rd symbol regarding TRP-2 can still be found on the 9th symbol of TRP-1. Thus, in such scenarios where multiple symbols are preempted, this interleaved mapping approach may create better time-domain diversity when compared to the (Reversed and Shifted) solutions described above.

Still other variants include some combinations of the approaches described above. For example, partitioning could be combined with Interleaved Mapping. In such a case, each of the partitioned CBG parts may have the same or different interleaving patterns.

Further, the CBG level mapping approaches described above could be extended to other resource units. For example, CB level mapping approaches could involve CB level reversed, shifted, or interleaved mapping, with or without partitioning. Similarly, RE level mapping approaches could involve CB level reversed, shifted, or interleaved mapping, with or without partitioning. RV level mapping approaches are also possible, for example with overall reversed or shifted mapping, such as:

RV0->1->2->3 for TRP-#1 and

RV1->2->3->0 for TRP-#2

or overall interleaved mapping, such as:

RV0->1->2->3 for TRP-#1 and

RV2->0->3->1 for TRP-#2.

As described herein, aspects of the present disclosure provide resource mapping techniques that may help maintain the advantages of diversity in NC-JT, even in the presence of preemption.

The methods disclosed herein comprise one or more steps or actions for achieving the methods. The method steps and/or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. 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 with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” may include receiving (e.g., receiving information) , accessing (e.g., accessing data in a memory) and the like. Also, “determining” may include resolving, selecting, choosing, establishing and the like.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to 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 herein, but is to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Unless specifically stated otherwise, the term “some” refers to one or more. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. §112 (f) unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for. ”

The various operations of methods described above may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and/or software component (s) and/or module (s) , including, but not limited to a circuit, an application specific integrated circuit (ASIC) , or processor. Generally, where there are operations illustrated in figures, those operations may have corresponding counterpart means-plus-function components with similar numbering. For example, operations 800 of FIG. 8 may be performed by the various processors of the base station 110 shown in FIG. 4, while operations 900 of FIG. 9 may be performed by the various processors of the base station 120 shown in FIG. 4

The various illustrative logical blocks, modules and circuits described in connection with the present disclosure may be implemented or performed with a general purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

If implemented in hardware, an example hardware configuration may comprise a processing system in a wireless node. The processing system may be implemented with a bus architecture. The bus may include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. The bus may link together various circuits including a processor, machine-readable media, and a bus interface. The bus interface may be used to connect a network adapter, among other things, to the processing system via the bus. The network adapter may be used to implement the signal processing functions of the PHY layer. In the case of a user terminal 120 (see FIG. 1) , a user interface (e.g., keypad, display, mouse, joystick, etc. ) may also be connected to the bus. The bus may also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further. The processor may be implemented with one or more general-purpose and/or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuitry that can execute software. Those skilled in the art will recognize how best to implement the described functionality for the processing system depending on the particular application and the overall design constraints imposed on the overall system.

If implemented in software, the functions may be stored or transmitted over as one or more instructions or code on a computer readable medium. Software shall be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media include both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general processing, including the execution of software modules stored on the machine-readable storage media. A computer-readable storage medium may be coupled to a processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. By way of example, the machine-readable media may include a transmission line, a carrier wave modulated by data, and/or a computer readable storage medium with instructions stored thereon separate from the wireless node, all of which may be accessed by the processor through the bus interface. Alternatively, or in addition, the machine-readable media, or any portion thereof, may be integrated into the processor, such as the case may be with cache and/or general register files. Examples of machine-readable storage media may include, by way of example, RAM (Random Access Memory) , flash memory, ROM (Read Only Memory) , PROM (Programmable Read-Only Memory) , EPROM (Erasable Programmable Read-Only Memory) , EEPROM (Electrically Erasable Programmable Read-Only Memory) , registers, magnetic disks, optical disks, hard drives, or any other suitable storage medium, or any combination thereof. The machine-readable media may be embodied in a computer-program product.

A software module may comprise a single instruction, or many instructions, and may be distributed over several different code segments, among different programs, and across multiple storage media. The computer-readable media may comprise a number of software modules. The software modules include instructions that, when executed by an apparatus such as a processor, cause the processing system to perform various functions. The software modules may include a transmission module and a receiving module. Each software module may reside in a single storage device or be distributed across multiple storage devices. By way of example, a software module may be loaded into RAM from a hard drive when a triggering event occurs. During execution of the software module, the processor may load some of the instructions into cache to increase access speed. One or more cache lines may then be loaded into a general register file for execution by the processor. When referring to the functionality of a software module below, it will be understood that such functionality is implemented by the processor when executing instructions from that software module.

Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared (IR) , radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, include compact disc (CD) , laser disc, optical disc, digital versatile disc (DVD) , floppy disk, and

disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Thus, in some aspects computer-readable media may comprise non-transitory computer-readable media (e.g., tangible media) . In addition, for other aspects computer-readable media may comprise transitory computer-readable media (e.g., a signal) . Combinations of the above should also be included within the scope of computer-readable media.

Thus, certain aspects may comprise a computer program product for performing the operations presented herein. For example, such a computer program product may comprise a computer-readable medium having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein. For example, instructions for performing the operations described herein and illustrated in FIG. 10 and FIG. 12.

Further, it should be appreciated that modules and/or other appropriate means for performing the methods and techniques described herein can be downloaded and/or otherwise obtained by a user terminal and/or base station as applicable. For example, such a device can be coupled to a server to facilitate the transfer of means for performing the methods described herein. Alternatively, various methods described herein can be provided via storage means (e.g., RAM, ROM, a physical storage medium such as a compact disc (CD) or floppy disk, etc. ) , such that a user terminal and/or base station can obtain the various methods upon coupling or providing the storage means to the device. Moreover, any other suitable technique for providing the methods and techniques described herein to a device can be utilized.

It is to be understood that the claims are not limited to the precise configuration and components illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

A method for wireless communication by a network entity, comprising:

determining a time domain resource mapping rule for transmitting a codeword of a scheduled joint data transmission of a first type from a group of transmitting entities to a user equipment (UE) , wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword; and

transmitting the codeword according to the determined time domain resource mapping rule.
The method of claim 1, wherein each of the transmitting entities in the group is associated with at least one of a virtual cell ID or a demodulation reference signal (DMRS) port group ID.
The method of claim 1, wherein:

the scheduled joint data transmission is subject to potential interference caused by data transmission of a second type; and

the different mapping rules are designed to reduce the impact of the potential interference.
The method of claim 3, wherein:

the first type of data transmission comprises an enhanced mobile broadband (eMBB) data transmission; and

the second type of data transmission comprises an ultra-reliable low latency communication (URLCC) data transmission.
The method of claim 1, further comprising configuring the UE with the time domain resource mapping rules via at least one of downlink control information (DCI) or radio resource control (RRC) signaling.
The method of claim 1, wherein:

the group comprises N transmitting entities; and

different subsets of the N transmitting entities share the same time domain resource mapping rules.
The method of claim 6, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, an indication of which time domain resource mapping rule is shared by each of the different subsets.
The method of claim 1, wherein the time domain resource mapping rules comprise unit-level time domain resource mapping rules that map M units of a same redundancy version (RV) of the codeword to time domain resources.
The method of claim 8, wherein the units comprise at least one of code block (CBs) , code block groups (CBGs) , or resource elements (REs) .
The method of claim 8, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 8, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the M units to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 11, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of S.
The method of claim 8, wherein:

the M units are partitioned in to subsets of P units; and

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 13, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 8, wherein:

the M units are partitioned in to subsets of P units;

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 15, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 8, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the M units to time domain resources according to a second pattern that results in interleaving the M units in a randomized order.
The method of claim 17, wherein the randomized order is based, at least in part, on a demodulation reference signal (DMRS) port group index associated with a transmitting entity applying the mapping rule.
The method of claim 17, wherein the randomized order is based, at least in part, on an identifier associated with the UE.
The method of claim 17, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, information regarding the randomized order.
The method of claim 8, wherein:

the M units are partitioned in to subsets of P units;

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a second pattern that results in interleaving the P units in a randomized order.
The method of claim 21, wherein the randomized order is based, at least in part, on a demodulation reference signal (DMRS) port group index associated with a transmitting entity applying the mapping rule.
The method of claim 21, wherein the randomized order is based, at least in part, on an identifier associated with the UE.
The method of claim 21, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, information regarding the randomized order.
The method of claim 21, further comprising providing, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 1, wherein the time domain resource mapping rules comprise redundancy version (RV) -level time domain resource mapping rules that map different RVs of the codeword to time domain resources.
The method of claim 26, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 26, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the different RVs to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 26, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the different RVs to time domain resources according to a second pattern that results in interleaving the different RVs in a randomized order.
A method for wireless communication by a user equipment (UE) , comprising:

receiving codewords of a joint data transmission of a first type from a group of transmitting entities;

determining a time domain resource mapping rule used by each of the transmitting entities for transmitting their respective codeword, wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword;

decoding each codeword according to the time domain mapping rule applied by the corresponding transmitting entity; and

combining decoding results for each codeword.
The method of claim 30, wherein each of the transmitting entities in the group is associated with at least one of a virtual cell ID or a demodulation reference signal (DMRS) port group ID.
The method of claim 30, wherein:

the scheduled joint data transmission is subject to potential interference caused by data transmission of a second type; and

the different mapping rules are designed to reduce the impact of the potential interference.
The method of claim 32, wherein:

the first type of data transmission comprises an enhanced mobile broadband (eMBB) data transmission; and

the second type of data transmission comprises an ultra-reliable low latency communication (URLCC) data transmission.
The method of claim 30, further comprising receiving signaling configuring the UE with the time domain resource mapping rules via at least one of downlink control information (DCI) or radio resource control (RRC) signaling.
The method of claim 30, wherein:

the group comprises N transmitting entities; and

different subsets of the N transmitting entities share the same time domain resource mapping rules.
The method of claim 35, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, an indication of which time domain resource mapping rule is shared by each of the different subsets.
The method of claim 30, wherein the time domain resource mapping rules comprise unit-level time domain resource mapping rules that map M units of a same redundancy version (RV) of the codeword to time domain resources.
The method of claim 37, wherein the units comprise at least one of code block (CBs) , code block groups (CBGs) , or resource elements (REs) .
The method of claim 37, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 37, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the M units to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 40, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of S.
The method of claim 37, wherein:

the M units are partitioned in to subsets of P units; and

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 42, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 37, wherein:

the M units are partitioned in to subsets of P units;

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 44, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 37, wherein:

at least one of the time domain resource mapping rules maps the M units to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the M units to time domain resources according to a second pattern that results in interleaving the M units in a randomized order.
The method of claim 46, wherein the randomized order is based, at least in part, on a demodulation reference signal (DMRS) port group index associated with a transmitting entity applying the mapping rule.
The method of claim 46, wherein the randomized order is based, at least in part, on an identifier associated with the UE.
The method of claim 46, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, information regarding the randomized order.
The method of claim 37, wherein:

the M units are partitioned in to subsets of P units;

at least one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the P units of each partition to time domain resources according to a second pattern that results in interleaving the P units in a randomized order.
The method of claim 50, wherein the randomized order is based, at least in part, on a demodulation reference signal (DMRS) port group index associated with a transmitting entity applying the mapping rule.
The method of claim 50, wherein the randomized order is based, at least in part, on an identifier associated with the UE.
The method of claim 50, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, information regarding the randomized order.
The method of claim 50, further comprising receiving, via at least one of downlink control information (DCI) or radio resource control (RRC) signaling, a value of P.
The method of claim 30, wherein the time domain resource mapping rules comprise redundancy version (RV) -level time domain resource mapping rules that map different RVs of the codeword to time domain resources.
The method of claim 55, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources in a reverse order relative to another one of the time domain resource mapping rules.
The method of claim 55, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources according to a first sequence; and

at least another one of the time domain resource mapping rules maps the different RVs to time domain resources according to a second sequence that is generated by shifting the first sequence by a shift offset of S units.
The method of claim 55, wherein:

at least one of the time domain resource mapping rules maps the different RVs to time domain resources according to a first pattern; and

at least another one of the time domain resource mapping rules maps the different RVs to time domain resources according to a second pattern that results in interleaving the different RVs in a randomized order.
An apparatus for wireless communication by a network entity, comprising:

means for determining a time domain resource mapping rule for transmitting a codeword of a scheduled joint data transmission of a first type from a group of transmitting entities to a user equipment (UE) , wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword; and

means for transmitting the codeword according to the determined time domain resource mapping rule.
An apparatus for wireless communication by a user equipment (UE) , comprising:

means for receiving codewords of a joint data transmission of a first type from a group of transmitting entities;

means for determining a time domain resource mapping rule used by each of the transmitting entities for transmitting their respective codeword, wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword;

means for decoding each codeword according to the time domain mapping rule applied by the corresponding transmitting entity; and

means for combining decoding results for each codeword.
An apparatus for wireless communication by a network entity, comprising:

at least one processor configured to determine a time domain resource mapping rule for transmitting a codeword of a scheduled joint data transmission of a first type from a group of transmitting entities to a user equipment (UE) , wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword; and

a transmitter configured to transmit the codeword according to the determined time domain resource mapping rule.
An apparatus for wireless communication by a user equipment (UE) , comprising:

a receiver configured to receive codewords of a joint data transmission of a first type from a group of transmitting entities; and

a processor configured to determine a time domain resource mapping rule used by each of the transmitting entities for transmitting their respective codeword, wherein different transmitting entities of the group use different time domain resource mapping rules for transmitting the same codeword, decode each codeword according to the time domain mapping rule applied by the corresponding transmitting entity, and combine decoding results for each codeword.