WO2021195819A1

WO2021195819A1 - Sub-resource block transmission

Info

Publication number: WO2021195819A1
Application number: PCT/CN2020/081971
Authority: WO
Inventors: Min Huang; Jing Dai; Qiaoyu Li; Chao Wei
Original assignee: Qualcomm Incorporated
Priority date: 2020-03-30
Filing date: 2020-03-30
Publication date: 2021-10-07

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a user equipment (UE) may receive a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB. The second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth. The UE may transmit the RB on a physical uplink shared channel according to the configuration. Numerous other aspects are provided.

Description

SUB-RESOURCE BLOCK TRANSMISSION

FIELD OF THE DISCLOSURE

Aspects of the present disclosure generally relate to wireless communication and to techniques and apparatuses for sub-resource block transmission.

BACKGROUND

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical 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, and/or the like) . Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency-division multiple access (FDMA) systems, orthogonal frequency-division multiple access (OFDMA) systems, single-carrier frequency-division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and Long Term Evolution (LTE) . LTE/LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP) .

A wireless communication network may include a number of base stations (BSs) that can support communication for a number of user equipment (UEs) . A user equipment (UE) may communicate with a base station (BS) via the downlink and uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail herein, a BS may be referred to as a Node B, a gNB, an access point (AP) , a radio head, a transmit receive point (TRP) , a New Radio (NR) BS, a 5G Node B, and/or the like.

The above multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipment to communicate on a municipal, national, regional, and even global level. New Radio (NR) , which may also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (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 orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL) , using CP-OFDM and/or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM) ) on the uplink (UL) , as well as supporting 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 LTE and NR technologies. Preferably, these improvements should be applicable to other multiple access technologies and the telecommunication standards that employ these technologies.

SUMMARY

In some aspects, a method of wireless communication, performed by a user equipment (UE) , may include receiving a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB. The second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth. The method may include transmitting the RB on a physical uplink shared channel according to the configuration.

In some aspects, a method of wireless communication, performed by a base station, may include determining a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB. The second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth. The method may include receiving, from the UE, the RB on a physical uplink shared channel according to the configuration.

In some aspects, a UE for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to receive a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB. The second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth. The memory and the one or more processors may be configured to transmit the RB on a physical uplink shared channel according to the configuration.

In some aspects, a base station for wireless communication may include a memory and one or more processors operatively coupled to the memory. The memory and the one or more processors may be configured to determine a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB. The second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth. The memory and the one or more processors may be configured to receive, from the UE, the RB on a physical uplink shared channel according to the configuration.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a UE, may cause the one or more processors to receive a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, wherein the second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth, and transmit the RB on a physical uplink shared channel according to the configuration.

In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. The one or more instructions, when executed by one or more processors of a base station, may cause the one or more processors to determine a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, wherein the second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth, and receive, from the UE, the RB on a physical uplink shared channel according to the configuration.

In some aspects, an apparatus for wireless communication may include means for receiving a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, wherein the second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth, and means for transmitting the RB on a physical uplink shared channel according to the configuration.

In some aspects, an apparatus for wireless communication may include means for determining a configuration specifying that DMRS resource elements REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, wherein the second bandwidth may be smaller than the first bandwidth and the first bandwidth may fully overlap the second bandwidth, means for transmitting the configuration to a UE, and means for receiving, from the UE, the RB on a physical uplink shared channel according to the configuration.

Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and/or processing system as substantially described herein with reference to and as illustrated by the drawings and specification.

The foregoing has outlined rather broadly the features and technical advantages of examples according to the disclosure in order that the detailed description that follows may be better understood. Additional features and advantages will be described hereinafter. The conception and specific examples disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. Characteristics of the concepts disclosed herein, both their organization and method of operation, together with associated advantages will be better understood from the following description when considered in connection with the accompanying figures. Each of the figures is provided for the purposes of illustration and description, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

So that 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 appended 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. The same reference numbers in different drawings may identify the same or similar elements.

Fig. 1 is a block diagram conceptually illustrating an example of a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 2 is a block diagram conceptually illustrating an example of a base station in communication with a user equipment (UE) in a wireless communication network, in accordance with various aspects of the present disclosure.

Fig. 3 is a diagram illustrating an example of a slot format, in accordance with various aspects of the present disclosure.

Fig. 4 is a diagram illustrating an example of a technique for enhancing uplink coverage, in accordance with various aspects of the present disclosure.

Fig. 5 is a diagram illustrating examples of resource block (RB) structures for regular New Radio UEs, in accordance with various aspects of the present disclosure.

Fig. 6 is a diagram illustrating examples of sub-RB configurations, in accordance with various aspects of the present disclosure.

Fig. 7 is a diagram illustrating an example of sub-RB transmission, in accordance with various aspects of the present disclosure.

Fig. 8 is a diagram illustrating an example process performed, for example, by a UE, in accordance with various aspects of the present disclosure.

Fig. 9 is a diagram illustrating an example process performed, for example, by a base station, in accordance with various aspects of the present disclosure.

DETAILED DESCRIPTION

Various aspects of the disclosure are described more fully hereinafter with reference to the accompanying drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. 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.

Several aspects of telecommunication systems will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and/or the like (collectively referred to as “elements” ) . These elements may be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.

It should be noted that 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.

Fig. 1 is a diagram illustrating a wireless network 100 in which aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. The wireless network 100 may include a number of BSs 110 (shown as BS 110a, BS 110b, BS 110c, and BS 110d) and other network entities. A BS is an entity that communicates with user equipment (UEs) and may also be referred to as a base station, a NR BS, a Node B, a gNB, a 5G node B (NB) , an access point, a transmit receive point (TRP) , and/or the like. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and/or a BS subsystem serving this coverage area, depending on the context in which the term is used.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or another type of cell. 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 association with the femto cell (e.g., UEs in a closed subscriber group (CSG) ) . 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, a BS 110a may be a macro BS for a macro cell 102a, a BS 110b may be a pico BS for a pico cell 102b, and a BS 110c may be a femto BS for a femto cell 102c. A BS may support one or multiple (e.g., three) cells. The terms “eNB” , “base station” , “NR BS” , “gNB” , “TRP” , “AP” , “node B” , “5G NB” , and “cell” may be used interchangeably herein.

In some aspects, 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 aspects, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection, a virtual network, and/or the like using any suitable transport network.

Wireless network 100 may also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that can relay transmissions for other UEs. In the example shown in Fig. 1, a relay station 110d may communicate with macro BS 110a and a UE 120d in order to facilitate communication between BS 110a and UE 120d. A relay station may also be referred to as a relay BS, a relay base station, a relay, and/or the like.

Wireless network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, and/or the like. These different types of BSs may have different transmit power levels, different coverage areas, and different impacts on interference in wireless network 100. For example, macro BSs may have a high transmit power level (e.g., 5 to 40 watts) whereas pico BSs, femto BSs, and relay BSs may have lower transmit power levels (e.g., 0.1 to 2 watts) .

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

UEs 120 (e.g., 120a, 120b, 120c) may be dispersed throughout wireless network 100, and each UE may be stationary or mobile. A UE may also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, and/or the like. A UE may be a cellular phone (e.g., 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, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, biometric sensors/devices, wearable devices (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet) ) , an entertainment device (e.g., a music or video device, or a satellite radio) , a vehicular component or sensor, smart meters/sensors, 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) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, and/or the like, that may communicate with a base station, 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, and/or may be implemented as NB-IoT (narrowband internet of things) devices. Some UEs may be considered a Customer Premises Equipment (CPE) . UE 120 may be included inside a housing that houses components of UE 120, such as processor components, memory components, and/or the like. In some aspects, the processor components and the memory components may be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) may be operatively coupled, communicatively coupled, electronically coupled, electrically coupled, and/or the like.

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, and/or the like. A frequency may also be referred to as a carrier, a frequency channel, and/or the like. 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.

In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly using one or more sidelink channels (e.g., without using a base station 110 as an intermediary to communicate with one another) . For example, the UEs 120 may communicate using peer-to-peer (P2P) communications, device-to-device (D2D) communications, a vehicle-to-everything (V2X) protocol (e.g., which may include a vehicle-to-vehicle (V2V) protocol, a vehicle-to-infrastructure (V2I) protocol, and/or the like) , a mesh network, and/or the like. In this case, the UE 120 may perform scheduling operations, resource selection operations, and/or other operations described elsewhere herein as being performed by the base station 110.

As indicated above, Fig. 1 is provided as an example. Other examples may differ from what is described with regard to Fig. 1.

Fig. 2 shows a block diagram of a design 200 of base station 110 and UE 120, which may be one of the base stations and one of the UEs in Fig. 1. Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general T ≥ 1 and R ≥ 1.

At base station 110, a transmit processor 220 may receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS (s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI) and/or the like) and control information (e.g., CQI requests, grants, upper layer signaling, and/or the like) and provide overhead symbols and control symbols. Transmit processor 220 may also generate reference symbols for reference signals (e.g., the cell-specific reference signal (CRS) ) and synchronization signals (e.g., the primary synchronization signal (PSS) and secondary synchronization signal (SSS) ) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and/or the reference symbols, if applicable, and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM and/or the like) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. T downlink signals from modulators 232a through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, the synchronization signals can be generated with location encoding to convey additional information.

At UE 120, antennas 252a through 252r may receive the downlink signals from base station 110 and/or other base stations and may provide received signals to demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM and/or the like) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for UE 120 to a data sink 260, and provide decoded control information and system information to a controller/processor 280. A channel processor may determine reference signal received power (RSRP) , received signal strength indicator (RSSI) , reference signal received quality (RSRQ) , channel quality indicator (CQI) , and/or the like. In some aspects, one or more components of UE 120 may be included in a housing.

On the uplink, at UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, CQI, and/or the like) from controller/processor 280. Transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, and/or the like) , and transmitted to base station 110. At base station 110, the uplink signals from UE 120 and other UEs may be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to controller/processor 240. Base station 110 may include communication unit 244 and communicate to network controller 130 via communication unit 244. Network controller 130 may include communication unit 294, controller/processor 290, and memory 292.

Controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform one or more techniques associated with sub-resource block (RB) transmission, as described in more detail elsewhere herein. For example, controller/processor 240 of base station 110, controller/processor 280 of UE 120, and/or any other component (s) of Fig. 2 may perform or direct operations of, for example, process 800 of Fig. 8, process 900 of Fig. 9, and/or other processes as described herein.

Memories

242 and 282 may store data and program codes for base station 110 and UE 120, respectively. In some aspects, memory 242 and/or memory 282 may comprise a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, interpreting, and/or the like) by one or more processors of the base station 110 and/or the UE 120, may perform or direct operations of, for example, process 800 of Fig. 8, process 900 of Fig. 9, and/or other processes as described herein. In some aspects, executing instructions may include running the instructions, converting the instructions, compiling the instructions, interpreting the instructions, and/or the like. A scheduler 246 may schedule UEs for data transmission on the downlink and/or uplink.

In some aspects, UE 120 may include means for receiving a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, where the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth, means for transmitting the RB on a physical uplink shared channel (PUSCH) according to the configuration, and/or the like. In some aspects, such means may include one or more components of UE 120 described in connection with Fig. 2, such as controller/processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, and/or the like.

In some aspects, base station 110 may include means for determining a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, where the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth, means for transmitting the configuration to a UE, means for receiving, from the UE, the RB on a PUSCH according to the configuration, and/or the like. In some aspects, such means may include one or more components of base station 110 described in connection with Fig. 2, such as antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller/processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, and/or the like.

As indicated above, Fig. 2 is provided as an example. Other examples may differ from what is described with regard to Fig. 2.

Fig. 3 is a diagram illustrating an example 300 of a slot format, in accordance with various aspects of the present disclosure. As shown in Fig. 3, time-frequency resources in a radio access network may be partitioned into RBs, shown by a single RB 305. An RB 305 is sometimes referred to as a physical resource block (PRB) . An RB 305 includes a set of subcarriers (e.g., 12 subcarriers) and a set of symbols (e.g., 14 symbols) that are schedulable by a base station as a unit. In some aspects, an RB 305 may include a set of subcarriers in a single slot. As shown, a single time-frequency resource included in an RB 305 may be referred to as RE 310. An RE 310 may include a single subcarrier (e.g., in frequency) and a single symbol (e.g., in time) . A symbol may be referred to as an orthogonal frequency division multiplexing (OFDM) symbol. An RE 310 may be used to transmit one modulated symbol, which may be a real value or a complex value.

In some telecommunication systems (e.g., NR) , RBs 305 may span 12 subcarriers with a subcarrier spacing of, for example, 15 kilohertz (kHz) , 30 kHz, 60 kHz, or 120 kHz, among other examples, over a 0.1 millisecond (ms) duration. A radio frame may include 40 slots and may have a length of 10 ms. Consequently, each slot may have a length of 0.25 ms. However, a slot length may vary depending on a numerology used to communicate (e.g., a subcarrier spacing, a cyclic prefix format, and/or the like) . A slot may be configured with a link direction (e.g., downlink or uplink) for transmission. In some aspects, the link direction for a slot may be dynamically configured.

As indicated above, Fig. 3 is provided as an example. Other examples may differ from what is described with respect to Fig. 3.

Fig. 4 is a diagram illustrating an example 400 of a technique for enhancing uplink coverage, in accordance with various aspects of the present disclosure. Fig. 4 shows an RB with DMRS REs and data REs spanning a same narrow bandwidth. This technique is used by, for example, Narrow Band Internet of Things (NB-IoT) devices that may suffer from a large pathloss. Such devices may lie at a cell edge or in a coverage hole (e.g., blocked by a high building) . The narrow bandwidth on an uplink transfer channel may be referred to as NB-PUSCH and may be less than one RB (e.g., 1, 3, or 6 frequency subcarriers, or tones) . In this way, a UE may concentrate transmission power into a smaller frequency bandwidth so that a transmit power at each RE is increased. In this technique, DMRSs of NB-PUSCH use a same frequency resource or bandwidth as PUSCH data REs. For example, DMRS REs may occupy 1 or 3 symbols in the middle of the RB, while data REs occupy all subcarriers of the NB-PUSCH bandwidth. In other words, a bandwidth of the DMRSs and a bandwidth of the data REs are the same.

As indicated above, Fig. 4 is provided as an example. Other examples may differ from what is described with respect to Fig. 4.

Fig. 5 is a diagram illustrating examples 500, 502 of RB structures for regular NR UEs, in accordance with various aspects of the present disclosure. An RB structure may allocate REs for different purposes, including for DMRS. A code-division multiplexing (CDM) group includes REs interleaved in subcarriers in a comb pattern, and DMRSs for the PUSCH of an NR UE (NR-PUSCH) may be divided into 2 or 3 CDM groups. Fig. 5 shows an example 500 of an RB structure for a regular NR UE with DMRS REs in CDM group 1 and an example 502 with DMRS REs in CDM group 2. Fig. 5 shows that the DMRS REs in CDM group 1 are in different subcarriers than the DMRS REs in CDM group 2.

Some aspects in NR may enhance uplink coverage for a UE at a cell edge or in a coverage hole, such as decreasing transmission bandwidth for NB-IoT devices as described in connection with Fig. 4. Decreasing the transmission bandwidth can boost a transmit power at each RE and thus improve a signal to noise plus interference ratio at a receiver. However, simply decreasing the transmission bandwidth is inefficient, because an NB-IoT UE does not support co-transmission with another regular NR UE (i.e., NR UEs that are not at a cell edge or in a coverage hole) at the same frequency resource (e.g., bandwidth) . An NB-IoT UE and a regular NR UE cannot co-transmit using multi-user MIMO (MU-MIMO) since the UEs have different DMRS formats. Also, because DMRSs are divided into CDM groups, once an uplink RB is allocated to an NB-IoT UE for NB-PUSCH transmission, the uplink RB cannot be simultaneously allocated to another regular NR UE for NR-PUSCH transmission.

Another problem for transmissions on a PUSCH (including NB-PUSCH) is weak channel estimation performance at edge REs of a bandwidth in an RB, and the problem is greater for UEs at a cell edge or in a coverage hole. Channel estimation for data REs in the middle of the bandwidth may rely on a greater number of adjacent DMRS REs than channel estimation for data REs at an edge of the bandwidth. Therefore, the data REs at the edge of the frequency resource may have worse channel estimation performance due to fewer DMRS REs that can contribute to the channel estimation.

As indicated above, Fig. 5 provides some examples. Other examples may differ from what is described with respect to Fig. 5.

Due to the interleaved comb pattern of DMRS REs in a CDM group, if an energy per RE (EPRE) and a bandwidth are identical between a DMRS RE and a data RE, a total transmission power of one DMRS symbol is one-half of a total transmission power of one data symbol. This means that there is unused transmit power, which provides some room to enhance channel estimation performance for edge REs of a PUSCH and for NR UEs at a cell edge or in a coverage hole. According to various aspects described herein, a UE may use some of this unused transmit power to improve the channel estimation performance at the edge REs. For example, a UE may use a narrower bandwidth of an RB for data REs than for DMRS REs. As a result, the UE may use a higher transmit power for each single data RE in a PUSCH transmission and improve a quality of PUSCH transmissions. The narrower bandwidth transmissions of data REs may be referred to as sub-RB transmissions.

Fig. 6 is a diagram illustrating examples 600, 602, 604 of sub-RB configurations, in accordance with various aspects of the present disclosure. Fig. 6 shows an example 600 of a sub-RB configuration of an RB structure for PUSCH transmissions. In some aspects, a sub-RB configuration may specify that DMRS REs and data REs span different bandwidths within an RB, where a bandwidth of DMRS REs covers a bandwidth of data REs. For example, DMRS REs may span a whole RB bandwidth in a comb pattern, while data REs span only half the RB bandwidth in a continuous pattern. Example 600 shows DMRS REs that span a first bandwidth of 12 subcarriers (tones) in a comb pattern (e.g., every two subcarriers) , while data REs span a second bandwidth of 6 subcarriers continuously. More generally, in some aspects, DMRS REs may span a first bandwidth of m subcarriers in a comb pattern, while data REs span a second bandwidth of n subcarriers in a continuous pattern, where n < m <=2n. Although DMRS REs span a larger bandwidth, the DMRS REs are located with intervals in between such that a total transmit power of a DMRS symbol can be identical to or no larger than a total transmit power of a data symbol.

Fig. 6 shows an example 602 of a sub-RB configuration where, in some aspects, the bandwidth of the data REs is located in the middle of the bandwidth of the DMRS REs. In some aspects, the middle of the bandwidth may include a fourth subcarrier to a ninth subcarrier for a continuous data bandwidth of six subcarriers for the data REs. In some aspects, the bandwidth for the data REs may be considered to be in a middle of the RB even if the bandwidth is shifted one or two subcarriers –as long as the bandwidth does not include an edge subcarrier of the bandwidth of the DMRS REs. In some aspects, the comb pattern of DMRS REs may enable MU-MIMO between a sub-RB PUSCH and a regular NR PUSCH. This may increase cell throughput and spectrum efficiency. A sub-RB configuration with DMRS REs in a larger bandwidth than a bandwidth for data REs and/or locating the bandwidth for the data REs in the middle of the bandwidth for the DMRS REs may help improve channel estimation performance at edge subcarriers of data REs, improve PUSCH reception performance, and thus increase uplink coverage.

In some aspects, a sub-RB configuration may specify that a bandwidth of the data REs starts in a first set of subcarriers for a first set of symbols of an RB and then hops to a second set of subcarriers for a second set of symbols of the RB. Fig. 6 shows an example 604 with DMRS REs in a bandwidth that spans 12 subcarriers in a comb pattern and data REs in a bandwidth that spans six subcarriers continuously. The bandwidth of the data REs is in a top half of subcarriers in the RB for a first half of data symbols of the RB and in a bottom half of subcarriers for a second half of the data symbols. Such a change in subcarriers within the RB may be referred to as sub-RB frequency-hopping and may improve diversity gain by mitigating interference from sub-RB transmissions of another UE (such as legacy NB-PUSCH transmissions) .

As indicated above, Fig. 6 provides some examples. Other examples may differ from what is described with respect to Fig. 6.

Fig. 7 is a diagram illustrating an example 700 of sub-RB transmission, in accordance with various aspects of the present disclosure. Fig. 7 shows a BS 710 (e.g., a BS 110 depicted in Figs. 1 and 2) and a UE 720 (e.g., a UE 120 depicted in Figs. 1 and 2) that may communicate with one another.

As shown by reference number 730, BS 710 may determine a configuration specifying that a UE transmit an RB on a PUSCH with DMRS REs spanning a first bandwidth of the RB and data REs spanning a second, smaller bandwidth of the RB. The first bandwidth for DMRS REs may fully overlap the second bandwidth for data REs. The configuration may be one of the sub-RB configurations (or any combination) illustrated in Fig. 6.

As shown by reference number 735, BS 710 may transmit the configuration to UE 720. BS 710 may transmit an RB index, information specifying a bandwidth or other frequency resources for data REs, a bandwidth or other frequency resources for DMRS REs, a DMRS comb pattern, a sub-RB frequency hopping pattern, and/or the like. The DMRS comb pattern may indicate which CDM group, bin, and/or the like to use for the DMRS REs. The sub-RB frequency hopping pattern may indicate which subcarriers are allocated to the data REs and for which symbols. BS 710 may transmit the configuration via radio resource control signaling, a medium access control control element (MAC CE) , downlink control information (DCI) , or a combination thereof.

As shown by reference number 740, UE 720 may transmit the RB (and other RBs) on the PUSCH according to the configuration. In other words, UE 720 may transmit communications to BS 710 on the PUSCH using an RB structure that corresponds to the sub-RB configuration thus improving communications for NR UEs that may be at a cell edge or in a coverage hole.

As indicated above, Fig. 7 is provided as an example. Other examples may differ from what is described with respect to Fig. 7.

Fig. 8 is a diagram illustrating an example process 800 performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process 800 is an example where the UE (e.g., UE 120 depicted in Figs. 1 and 2, UE 720 depicted in Fig. 7, and/or the like) performs operations associated with sub-RB transmission.

As shown in Fig. 8, in some aspects, process 800 may include receiving a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB (block 810) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may receive a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, as described above. In some aspects, the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth.

As further shown in Fig. 8, in some aspects, process 800 may include transmitting the RB on a PUSCH according to the configuration (block 820) . For example, the UE (e.g., using receive processor 258, transmit processor 264, controller/processor 280, memory 282, and/or the like) may transmit the RB on a PUSCH according to the configuration, as described above.

Process 800 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a first aspect, the configuration specifies that the first bandwidth spans all frequency sub-carriers of the RB in a comb pattern, and that the second bandwidth spans up to half of the frequency carriers of the RB in a continuous pattern.

In a second aspect, alone or in combination with the first aspect, the configuration specifies that a quantity of frequency subcarriers spanned by the first bandwidth is less than or equal to two times a quantity of frequency subcarriers spanned by the second bandwidth.

In a third aspect, alone or in combination with one or more of the first and second aspects, the configuration specifies that the second bandwidth spans six continuous frequency subcarriers.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the configuration specifies that the second bandwidth is located in the middle of the first bandwidth.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the configuration specifies that the second bandwidth spans a fourth frequency subcarrier to a ninth frequency subcarrier of the RB.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the configuration specifies that a first portion of the second bandwidth is located in a first set of symbols of the RB and that a second portion of the second bandwidth is located in a second set of symbols of the RB.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the first portion does not overlap with the second portion, and the first set of symbols does not overlap with the second set of symbols.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the first portion spans a first half of symbols of the RB, and the second portion spans a second half of symbols of the RB.

Although Fig. 8 shows example blocks of process 800, in some aspects, process 800 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 8. Additionally, or alternatively, two or more of the blocks of process 800 may be performed in parallel.

Fig. 9 is a diagram illustrating an example process 900 performed, for example, by a base station, in accordance with various aspects of the present disclosure. Example process 900 is an example where the base station (e.g., BS 110 depicted in Figs. 1 and 2, BS 710 depicted in Fig. 7, and/or the like) performs operations associated with sub-RB reception.

As shown in Fig. 9, in some aspects, process 900 may include determining a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB (block 910) . For example, the base station (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, and/or the like) may determine a configuration specifying that DMRS REs span a first bandwidth of an RB and that data REs span a second bandwidth of the RB, as described above. In some aspects, the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth.

As further shown in Fig. 9, in some aspects, process 900 may include transmitting the configuration to a UE (block 920) . For example, the base station (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, and/or the like) may transmit the configuration to a UE, as described above.

As further shown in Fig. 9, in some aspects, process 900 may include receiving, from the UE, the RB on a PUSCH according to the configuration (block 930) . For example, the base station (e.g., using transmit processor 220, receive processor 238, controller/processor 240, memory 242, and/or the like) may receive, from the UE, the RB on a PUSCH according to the configuration, as described above.

Process 900 may include additional aspects, such as any single aspect or any combination of aspects described below and/or in connection with one or more other processes described elsewhere herein.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, transmitting the configuration includes transmitting the configuration via one or more of a radio resource control signaling, a MAC CE, or downlink control information.

Although Fig. 9 shows example blocks of process 900, in some aspects, process 900 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Fig. 9. Additionally, or alternatively, two or more of the blocks of process 900 may be performed in parallel.

The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise form disclosed. Modifications and variations may be made in light of the above disclosure or may be acquired from practice of the aspects.

As used herein, the term “component” is intended to be broadly construed as hardware, firmware, and/or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, and/or a combination of hardware and software.

As used herein, satisfying a threshold may, depending on the context, refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, and/or the like.

It will be apparent that systems and/or methods described herein may be implemented in different forms of hardware, firmware, and/or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and/or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and/or methods were described herein without reference to specific software code-it being understood that software and hardware can be designed to implement the systems and/or methods based, at least in part, on the description herein.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features may be combined in ways not specifically recited in the claims and/or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of various aspects includes each dependent claim in combination with every other claim in the claim set. 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) .

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles “a” and “an” are intended to include one or more items, and may be used interchangeably with “one or more. ” Furthermore, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like) , and may be used interchangeably with “one or more. ” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has, ” “have, ” “having, ” and/or the like are intended to be open-ended terms. Further, the phrase “based on” is intended to mean “based, at least in part, on” unless explicitly stated otherwise.

Claims

A method of wireless communication performed by a user equipment (UE) , comprising:

receiving a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth; and

transmitting the RB on a physical uplink shared channel according to the configuration.
The method of claim 1, wherein the configuration specifies that the first bandwidth spans all frequency sub-carriers of the RB in a comb pattern, and that the second bandwidth spans up to half of the frequency carriers of the RB in a continuous pattern.
The method of claim 1, wherein the configuration specifies that a quantity of frequency subcarriers spanned by the first bandwidth is less than or equal to two times a quantity of frequency subcarriers spanned by the second bandwidth.
The method of claim 1, wherein the configuration specifies that the second bandwidth spans six continuous frequency subcarriers.
The method of claim 1, wherein the configuration specifies that the second bandwidth is located in the middle of the first bandwidth.
The method of claim 1, wherein the configuration specifies that the second bandwidth spans a fourth frequency subcarrier to a ninth frequency subcarrier of the RB.
The method of claim 1, wherein the configuration specifies that a first portion of the second bandwidth is located in a first set of symbols of the RB and that a second portion of the second bandwidth is located in a second set of symbols of the RB.
The method of claim 7, wherein the first portion does not overlap with the second portion, and the first set of symbols does not overlap with the second set of symbols.
The method of claim 7, wherein the first portion spans a first half of symbols of the RB, and the second portion spans a second half of symbols of the RB.
A method of wireless communication performed by a base station, comprising:

determining a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth;

transmitting the configuration to a user equipment (UE) ; and

receiving, from the UE, the RB on a physical uplink shared channel according to the configuration.
The method of claim 10, wherein the configuration specifies that the first bandwidth spans all frequency sub-carriers of the RB in a comb pattern, and that the second bandwidth spans up to half of the frequency carriers of the RB in a continuous pattern.
The method of claim 10, wherein the configuration specifies that a quantity of frequency subcarriers spanned by the first bandwidth is less than or equal to two times a quantity of frequency subcarriers spanned by the second bandwidth.
The method of claim 10, wherein the configuration specifies that the second bandwidth spans six continuous frequency subcarriers.
The method of claim 10, wherein the configuration specifies that the second bandwidth is located in the middle of the first bandwidth.
The method of claim 10, wherein the configuration specifies that the second bandwidth spans a fourth frequency subcarrier to a ninth frequency subcarrier of the RB.
The method of claim 10, wherein the configuration specifies that a first portion of the second bandwidth is located in a first set of symbols of the RB and that a second portion of the second bandwidth is located in a second set of symbols of the RB.
The method of claim 16, wherein the first portion does not overlap with the second portion, and the first set of symbols does not overlap with the second set of symbols.
The method of claim 16, wherein the first portion spans a first half of symbols of the RB, and the second portion spans a second half of symbols of the RB.
The method of claim 10, wherein transmitting the configuration includes transmitting the configuration via one or more of a radio resource control signaling, a medium access control control element, or downlink control information.
A user equipment for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

receive a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth; and

transmit the RB on a physical uplink shared channel according to the configuration.
A base station for wireless communication, comprising:

a memory; and

one or more processors operatively coupled to the memory, the memory and the one or more processors configured to:

determine a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth;

transmit the configuration to a user equipment (UE) ; and

receive, from the UE, the RB on a physical uplink shared channel according to the configuration.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising:

one or more instructions that, when executed by one or more processors of a user equipment, cause the one or more processors to:

receive a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth; and

transmit the RB on a physical uplink shared channel according to the configuration.
A non-transitory computer-readable medium storing one or more instructions for wireless communication, the one or more instructions comprising:

one or more instructions that, when executed by one or more processors of a base station, cause the one or more processors to:

determine a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth;

transmit the configuration to a user equipment (UE) ; and

receive, from the UE, the RB on a physical uplink shared channel according to the configuration.
An apparatus for wireless communication, comprising:

means for receiving a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth; and

means for transmitting the RB on a physical uplink shared channel according to the configuration.
An apparatus for wireless communication, comprising:

means for determining a configuration specifying that demodulation reference signal (DMRS) resource elements (REs) span a first bandwidth of a resource block (RB) and that data REs span a second bandwidth of the RB, wherein the second bandwidth is smaller than the first bandwidth and the first bandwidth fully overlaps the second bandwidth;

means for transmitting the configuration to a user equipment (UE) ; and

means for receiving, from the UE, the RB on a physical uplink shared channel according to the configuration.