WO2021087979A1

WO2021087979A1 - Wireless communication method for random access procedure

Info

Publication number: WO2021087979A1
Application number: PCT/CN2019/116696
Authority: WO
Inventors: Jianqiang DAI; Li Tian; Yuzhou HU
Original assignee: Zte Corporation
Priority date: 2019-11-08
Filing date: 2019-11-08
Publication date: 2021-05-14
Also published as: TW202114458A; CN114667793A

Abstract

Method, systems and devices for a random access procedure The method for use in a wireless terminal comprises transmitting, to a wireless network node, a message comprising a preamble and a payload for a random access procedure, wherein the preamble and a demodulation reference signal (DMRS) for a physical uplink shared channel (PUSCH) of the message indicates a configuration of transmitting the payload.

Description

Wireless Communication Method for Random Access Procedure

This document is directed generally to wireless communications and more particularly, to methods, apparatuses and systems for transmitting/receiving a message of a random access procedure in wireless communications.

In both the 4th Generation (4G) and the 5th Generation (5G) new radio (NR) mobile networks, before a user equipment (UE) sends data to a base station (BS) , the UE needs to obtain uplink synchronization and downlink synchronization with the BS. The uplink timing synchronization may be achieved by performing a random access procedure.

An exemplary 4-step random access procedure 10 is shown in FIG. 1. As shown in FIG. 1, a UE 100 transmits a random access channel (RACH) preamble in a message Msg1 to a BS 102. Once the preamble is received successfully by the BS 102, the BS 102 will send a message Msg2 back to the UE 100, in which a medium access control (MAC) random access response (RAR) is included as a response to the preamble. Once the MAC RAR with corresponding random access preamble (RAP) identifier (ID) is received, the UE 100 transmits a message Msg3 to the BS 102 with the grant carried in the MAC RAR. Once the message Msg3 is received, the BS 102 will send a message Msg4 back to the UE 100, in which some kind of contention resolution ID will be included for the purpose of contention resolution. A communication system merely relying on an initial access procedure as mentioned above will induce latency and cannot meet the needs of faster and newer communications in future network developments.

Thus, existing systems and methods for performing a random access procedure in a wireless communication are not entirely satisfactory.

This document relates to methods, systems, and devices for transmitting/receiving a message of a random access procedure in wireless communications.

The present disclosure relates to a wireless communication method for use in a wireless terminal. The wireless communication method comprises transmitting, to a wireless network node, a message comprising a preamble and a payload for a random access procedure, wherein the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH, of the message, indicate a configuration of transmitting the payload.

Various embodiments may preferably implement the following features:

Preferably, the configuration is indicated by a preamble index of the preamble.

Preferably, the configuration is indicated by a preamble group comprising the preamble.

Preferably, the DMRS is determined based on at least one of the preamble or a bandwidth part, BWP, corresponding to the configuration.

Preferably, the DMRS is determined based on at least one of the preamble or an index of the BWP.

Preferably, the DMRS is determined based on at least one of the preamble or a type of the BWP.

Preferably, the type of the BWP includes an initial BWP, an active BWP or a default BWP.

Preferably, a pseudo-random sequence generator of the DMRS is initiated by:

wherein,

relates to the number of symbols of a slot,

relates to a slot number within a frame, l is the symbol number within a slot, n _SCID is 0 or one of {0, 1} which is indicated by a DMRS field in downlink control information (DCI) associated with a transmission of the PUSCH (e.g. the payload) or by at least one higher layer parameter, and

is determined based on at least one higher layer parameter or be

which is related to the number of physical cell identities,

wherein at least one of

or

is further determined based on at least one of the preamble or the BWP corresponding to the configuration.

In this disclosure, the higher layer parameter may be at least one of a Medium access control (MAC) control element, MAC CE, or a radio resource control (RRC) message, or a RRC information element, RRC IE, or a signaling message of the wireless protocol higher than the physical layer (e.g. the MAC layer, the RRC layer, etc. ) .

Preferably, n _SCID is determined based on at least one of the preamble or the BWP corresponding to the configuration.

Preferably,

is determined based on at least one of the preamble or the BWP corresponding to the configuration.

Preferably, n _SCID is 0 and

is determined based on the BWP corresponding to the configuration.

Preferably, n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration.

Preferably, n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration and

is determined based on another one of the preamble or the BWP corresponding to the configuration.

Preferably, the configuration of transmitting the payload is indicated by the preamble, the DMRS of the PUSCH and at least one physical uplink shared channel interlace.

Preferably, the configuration comprises at least one of resource, a modulation coding scheme or demodulation reference signal information.

The present disclosure further relates to a wireless communication method for use in a wireless network node, comprising:

receiving, from a wireless terminal, a message comprising a preamble and a payload for a random access procedure, and

decoding the payload based on a configuration indicated by the preamble and a demodulation reference signal, DMRS for a physical uplink shared channel, PUSCH, of the message.

Various embodiments may preferably implement the following features:

Preferably, the configuration is indicated by a preamble index of the preamble.

Preferably, a pseudo-random sequence generator of the DMRS is initiated by:

wherein,

relates to the number of symbols of a slot,

relates to a slot number within a frame, l is the symbol number within a slot, n _SCID is 0 or one of {0, 1} which is indicated by a DMRS field in downlink control information (DCI) associated with a transmission of the PUSCH or by at least one higher layer parameter and

is determined based on at least one higher layer parameter or be

which is related to the number of physical cell identities,

wherein at least one of

or n _SCID is further determined based on at least one of the preamble or the BWP corresponding to the configuration.

Preferably, n _SCIS is determined based on at least one of the preamble or the BWP corresponding to the configuration.

Preferably,

Preferably, n _SCID is 0 and

is determined based on the BWP corresponding to the configuration.

The present disclosure relates to a wireless terminal. The wireless terminal comprises a communication unit configured to transmit, to a wireless network node, a comprising a preamble and a payload for a random access procedure, wherein the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH, of the message indicate a configuration of transmitting the payload.

Various embodiments may preferably implement the following feature:

Preferably, the wireless terminal further comprises a processor configured to perform the aforementioned wireless communication method for the wireless terminal.

The present disclosure relates to a wireless network node. The wireless network node comprises:

a communication unit, configured to receive, from a wireless terminal, a message comprising a preamble and a payload for a random access procedure, and

a processor, configured to decode the payload with a configuration indicated by the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH, of the message.

Various embodiments may preferably implement the following feature:

Preferably, the processor is further configured to perform the aforementioned wireless communication method for the wireless network node.

The present disclosure relates to a computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement the aforementioned wireless communication method.

The exemplary embodiments disclosed herein are directed to providing features that will become readily apparent by reference to the following description when taken in conjunction with the accompany drawings. In accordance with various embodiments, exemplary systems, methods, devices and computer program products are disclosed herein. It is understood, however, that these embodiments are presented by way of example and not limitation, and it will be apparent to those of ordinary skill in the art who read the present disclosure that various modifications to the disclosed embodiments can be made while remaining within the scope of the present disclosure.

Thus, the present disclosure is not limited to the exemplary embodiments and applications described and illustrated herein. Additionally, the specific order and/or hierarchy of steps in the methods disclosed herein are merely exemplary approaches. Based upon design preferences, the specific order or hierarchy of steps of the disclosed methods or processes can be re-arranged while remaining within the scope of the present disclosure. Thus, those of ordinary skill in the art will understand that the methods and techniques disclosed herein present various steps or acts in a sample order, and the present disclosure is not limited to the specific order or hierarchy presented unless expressly stated otherwise.

The above and other aspects and their implementations are described in greater detail in the drawings, the descriptions, and the claims.

FIG. 1 shows an example of a random access procedure.

FIG. 2 shows an example of a schematic diagram of a wireless terminal according to an embodiment of the present disclosure.

FIG. 3 shows an example of a schematic diagram of a wireless network node according to an embodiment of the present disclosure.

FIG. 4 shows an example of a random access process according to an embodiment of the present disclosure.

FIG. 5 shows configurations indicated by preamble groups according to an embodiment of the present disclosure.

FIG. 6 shows configurations indicated by the preamble groups and the DMRS sequences according to an embodiment of the present disclosure.

FIG. 7 shows configurations indicated by the preamble groups and the DMRS sequence sets according to an embodiment of the present disclosure.

FIG. 8 shows configurations indicated by the preamble groups and the DMRS sequences according to an embodiment of the present disclosure.

FIG. 9 shows configurations indicated by the preamble group and the DMRS sequence sets according to an embodiment of the present disclosure.

FIG. 10 shows a table of parameters of DMRS initialization sequence according to an embodiment of the present disclosure.

FIG. 11 shows a table of parameters of DMRS initialization sequence according to an embodiment of the present disclosure.

FIG. 12 shows a table of parameters of DMRS initialization sequence according to an embodiment of the present disclosure.

FIG. 13 shows configurations indicated by the preamble group and the DMRS sequence sets according to an embodiment of the present disclosure.

FIG. 2 relates to a schematic diagram of a wireless terminal 20 according to an embodiment of the present disclosure. The wireless terminal 20 may be a user equipment (UE) , a mobile phone, a laptop, a tablet computer, an electronic book or a portable computer system and is not limited herein. The wireless terminal 20 may include a processor 200 such as a microprocessor or Application Specific Integrated Circuit (ASIC) , a storage unit 210 and a communication unit 220. The storage unit 210 may be any data storage device that stores a program code 212, which is accessed and executed by the processor 200. Embodiments of the storage unit 212 include but are not limited to a subscriber identity module (SIM) , read-only memory (ROM) , flash memory, random-access memory (RAM) , hard-disk, and optical data storage device. The communication unit 220 may a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 200. In an embodiment, the communication unit 220 transmits and receives the signals via at least one antenna 222 shown in FIG. 2.

In an embodiment, the storage unit 210 and the program code 212 may be omitted and the processor 200 may include a storage unit with stored program code.

The processor 200 may implement any one of the steps in exemplified embodiments on the wireless terminal 20, e.g., by executing the program code 212.

The communication unit 220 may be a transceiver. The communication unit 220 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless network node (e.g. a base station) .

FIG. 3 relates to a schematic diagram of a wireless network node 30 according to an embodiment of the present disclosure. The wireless network node 30 may be a base station (BS) , a network entity, a Mobility Management Entity (MME) , Serving Gateway (S-GW) , Packet Data Network (PDN) Gateway (P-GW) , or Radio Network Controller (RNC) , and is not limited herein. The wireless network node 30 may include a processor 300 such as a microprocessor or ASIC, a storage unit 310 and a communication unit 320. The storage unit 310 may be any data storage device that stores a program code 312, which is accessed and executed by the processor 300. Examples of the storage unit 312 include but are not limited to a SIM, ROM, flash memory, RAM, hard-disk, and optical data storage device. The communication unit 320 may be a transceiver and is used to transmit and receive signals (e.g. messages or packets) according to processing results of the processor 300. In an example, the communication unit 320 transmits and receives the signals via at least one antenna 322 shown in FIG. 3.

In an embodiment, the storage unit 310 and the program code 312 may be omitted. The processor 300 may include a storage unit with stored program code.

The processor 300 may implement any steps described in exemplified embodiments on the wireless network node 30, e.g., via executing the program code 312.

The communication unit 320 may be a transceiver. The communication unit 320 may as an alternative or in addition be combining a transmitting unit and a receiving unit configured to transmit and to receive, respectively, signals to and from a wireless terminal (e.g. a user equipment) .

FIG. 4 relates to a schematic diagram of a process 40 according to an embodiment of the present disclosure. The process 40 is used for a random access procedure performed by a UE 400 for an access to a BS 402. As shown in FIG. 4, the UE 400 transmits a message MsgA to the BS 402 for the access to the BS 402 (e.g. for performing a random access procedure) , and the message MsgA includes a preamble and a corresponded payload. In response to the message MsgA, the BS 402 returns a message MsgB to the UE 400. In an embodiment, the message MsgA includes as least some of the messages Msg1 and Msg3 shown in FIG. 1 and the message MsgB includes at least some of the messages Msg2 and Msg4 shown in FIG. 1. According to FIG. 4, the UE 400 is able to access to the BS 402 via the two-step process 40.

In the two-step random access procedure (e.g. the process 40) , the preamble and the payload in the message MsgA are respectively transmitted in different uplink (UL) resources (e.g., different time resources, frequency resources and/or demodulation reference signal (DMRS) resources) . The receiver (e.g. the BS 402) of the message MsgA may acknowledge a configuration (comprising the UL resources, a modulation and coding scheme (MCS) , DMRS information, etc. ) of transmitting the preamble and be able to decode the preamble without additional indications. Although a configuration of transmitting the payload in the message MsgA may be pre-configured before the transmission of the message MsgA, the transmitter (e.g. the UE 400) may be pre-configured multiple configurations for transmitting the payload of the message MsgA and select one of the pre-configured configurations to transmit the payload in the message MsgA when transmitting the message MsgA. Under such a condition, the receiver (e.g. the BS 402) may have a problem of determining the configuration of transmitting the payload.

In an embodiment, the configuration of transmitting the payload of the message MsgA is indicated by the preamble of the message MsgA, so as to avoid an ambiguity issue of determining the configuration of transmitting the payload of the message MsgA in the 2-step random access procedure. Based on the indication of the preamble, the receiver (e.g. the BS 402) is able to effectively determine the configuration of transmitting the payload based on the preamble and to decode the payload based on the determined configuration. In an embodiment, the indicated configuration of transmitting the payload includes resources (e.g. time resources, frequency resources and/or DMRS resources) , a modulation and coding scheme (MCS) , DMRS information (e.g. the number of DMRS sequences) , etc.

In an embodiment, the configuration of transmitting the payload of the message MsgA is indicated by a preamble index of the preamble of the message MsgA. In another embodiment, the configuration of transmitting the payload of the message MsgA is indicated by a preamble group to which the preamble of the message MsgA belongs (i.e. by the preamble group comprising the preamble) . For example, when receiving the preamble of the message MsgA, the receiver determines the preamble index of the preamble and determines the configuration of transmitting the payload of the message MsgA directly based on the preamble index. In another example, the receiver determines the preamble group to which the preamble belongs when receiving the preamble of the message MsgA and determines the configuration of transmitting the payload of the message MsgA directly based on the preamble group comprising the preamble. In still another example, the receiver determines the preamble index of the preamble when receiving the preamble of the message MsgA, determines the preamble group to which the preamble belongs and determines the configuration of transmitting the payload of the message MsgA directly the preamble group comprising the preamble. After determining the configuration of transmitting the payload, the receiver is able to decode the payload based on the determined configuration.

FIG. 5 shows configurations indicated by preamble groups according an embodiment of the present disclosure. In FIG. 5, a preamble group A indicates a configuration C0 and another preamble group B indicates a configuration C1. In an example, the transmitter (e.g. the UE 400) transmits a random access message (i.e. the message MsgA) for a random access procedure and the random access message comprises a preamble with an index 0 and a payload. When receiving the random access message, the receiver (e.g. the BS 402) determines the index 0 of the preamble and determines that preamble with the index 0 belongs to the preamble group A. Based on associations shown in FIG. 5, the receiver determines that the configuration of transmitting the payload is the configuration C0 indicated by the preamble group A and accordingly decodes the payload based on the configuration C0.

In FIG. 5, the configurations C0 and C1 shown in FIG. 5 are associated to a bandwidth part (BWP) type BWP_T0. For example, the BWP type BWP_T0 associated to configurations C0 and C1 may be one of an initial BWP, an active BWP and a default BWP.

In an embodiment, the wireless network of the transmitter and/or the receiver may support multiple BWP types (e.g. the initial BWP, the active BWP, and/or the default BWP) . Under such a condition, more configurations may be preconfigured to the transmitter for supporting the multiple BWP types.

In an embodiment of the wireless network supporting multiple BWP types, each of the preamble groups may indicate a configuration of transmitting the payload for each of BWP types, wherein the configurations for different BWP types equip with different resources (e.g. time resources and/or frequency resources) . In this embodiment, the receiver may decode the payload based on each of the configurations associated with each of the preamble groups and would successfully decode the payload with one of the configurations with each of the preamble groups. For example, a preamble group may indicate a configuration C0 of a BWP type BWP_T0 and a configuration C1 of a BWP type BWP_T1. When receiving the message MsgA comprising the preamble of this preamble group, the receiver decodes the payload of the message MsgA with both the configurations C0 and C1 and would successfully decode the payload with either the configuration C0 or C1.

In an embodiment of the wireless network supporting multiple BWP types, the configuration of transmitting the payload in the message MsgA may be indicated by not only the preamble but also a DMRS (e.g. a DMRS sequence and/or a DMRS port) for a physical uplink shared channel (PUSCH) of the message. In other words, the receiver is able to determine the configuration of transmitting the payload in the message MsgA based on indications of the preamble in the message MsgA and the DMRS. Therefore, the receiver is able to effectively determine the configuration of transmitting the payload based on indications of the preamble and the DMRS.

In an embodiment, the wireless network may support more than 2 configurations in one BWP. For example, the wireless network may supports N configurations for radio resource control (RRC) idle/inactive UE and N configurations for RRC connected UE, wherein N is an integer up to 2.

In an embodiment, the receiver may determine the configuration of transmitting the payload in the message MsgA based on indications of not only the preamble (e.g. the preamble group comprising the preamble) but also a DMRS sequence/port of the payload. For example, the receiver may determine the preamble index of the preamble, determine the preamble group to which the preamble belong based on the preamble index and determine a plurality of configurations associated to the preamble group comprising the preamble. Next, the receiver may determine one of the configurations associated to the preamble group comprising the preamble as the configuration of transmitting the payload based on the DMRS sequence/port of the PUSCH (e.g. the payload) and accordingly decode the payload with the determined configuration.

FIG. 6 shows configurations indicated by the preamble groups and the DMRS sequences according to an embodiment of the present disclosure. As show in FIG. 6, the preamble group A indicates a configuration C0 of a BWP type BWP_T0 and a configuration C2 of a BWP type BWP_T1. Similarly, the preamble group B indicates a configuration C1 of the BWP type BWP_T0 and a configuration C3 of the BWP type BWP_T1. In an example, the BWP type BWP_T0 is one of the initial BWP and the active BWP and the BWP type BWP_T1 is another one of the initial BWP and the active BWP. On the other hand, the DMRS sequence with the index 0 (i.e. the DMRS sequence #0) indicates the configuration C0 of the BWP type BWP_T0 and the configuration C1 of the BWP type BWP_T0 and the DMRS sequence with the index 1 (i.e. the DMRS sequence #1) indicates the configuration C2 of the BWP type BWP_T1 and the configuration C3 of the BWP type BWP_T1. That is, the DMRS sequence #0 indicates MsgA PUSCH (e.g. payload) configurations of the BWP type BWP_T0 and the DMRS sequence #1 indicates MsgA PUSCH configurations of the BWP type BWP_T1.

In an embodiment, the DMRS sequences #0 and #1 shown in FIG. 6 may have different DMRS ports. Thus, the configuration of transmitting the payload may also be indicated by the DMRS port of the PUSCH (e.g. the payload) .

In the embodiment shown in FIG. 6, when the receiver receives the message MsgA comprising the preamble and the payload for the random access procedure, the receiver may firstly determine the preamble group to which the preamble belongs (e.g. based on the preamble index of the preamble) and then determine the configuration of transmitting the payload from the configurations associated to the preamble group comprising the preamble based on the DMRS sequence of the PUSCH (e.g. the payload) . For example, the receiver may determine that the preamble of the received message MsgA belongs to the preamble group A and the DMRS sequence of the PUSCH is the DMRS sequence #0. Based on indications of the preamble and the DMRS sequence, the receiver determines the configuration of transmitting the payload is the configuration C0 of the BWP type BWP_T0 and decodes the payload with the configuration C0.

In an embodiment, the configurations corresponding to each of BWP types may be indicated by a DMRS set comprising multiple DMRS sequences. That is, a configuration of transmitting the payload may be indicated by a plurality of DMRS sequences. FIG. 7 shows configurations indicated by the preamble groups and the DMRS sequence sets according to an embodiment of the present disclosure. In FIG. 7, the preamble group A indicates a configuration C0 of a BWP type BWP_T0 and a configuration C2 of a BWP type BWP_T1 and the preamble group B indicates a configuration C1 of the BWP type BWP_T0 and a configuration C3 of the BWP type BWP_T1. In addition, a DMRS set comprising DMRS sequences with index 0 and 1 (i.e. DMRS sequence #0 and DMRS sequence #1) indicates the configurations C0 and C1 of the BWP type BWP_T0 and a DMRS set comprising DMRS sequences with index 2 and 3 (i.e. DMRS sequence #2 and DMRS sequence #3) indicates the configurations C2 and C3 of the BWP type BWP_T1.

In the embodiment shown in FIG. 7, when the receiver receives the message MsgA comprising the preamble and the payload for the random access procedure, the receiver may firstly determine the preamble group to which the preamble belongs (e.g. based on the preamble index of the preamble) and then determines the configuration of transmitting the payload from the configurations associated with the preamble group comprising the preamble based on the DMRS sequence of the payload. For example, the receiver may determine that the preamble of the received message MsgA belongs to the preamble group A and that the DMRS sequence of the PUSCH of the message MsgA is the DMRS sequence #2. Based on indications of the preamble and the DMRS sequence of the payload, the receiver determines the configuration of transmitting the payload is the configuration C2 of the BWP type BWP_T0 and decodes the payload with the configuration C2. In an embodiment, the DMRS sets shown in FIG. 7 may be associated with different DMRS ports. Therefore, the configuration of transmitting the payload may also be indicated by the DMRS port of the PUSCH of the message MsgA.

In an embodiment, the DMRS ports in different code domain multiplexing (CDM) groups may be able to indicate configurations of different BWP types. For example, the DMRS ports in a CDM group CDM1 may indicate the configurations C0 and C1 of the BWP type BWP_T0 shown in FIG. 7 and the DMRS ports in another CDM group CDM2 may indicate the configurations C2 and C3 of the BWP type BWP_T1 shown in FIG. 7. In other words, the receiver may be able to determine the configuration of transmitting the payload in the message MsgA based on the indications of the preamble of the message MsgA and a CDM group to which the DMRS port of the PUSCH belongs.

In the embodiments shown in FIGS. 6 and 7, the preamble groups A and B are associated with the same DMRS sequences. In an embodiment, the preamble groups are respectively associated with different DMRS sequences. FIG. 8 shows configurations indicated by the preamble groups and the DMRS sequences according to an embodiment of the present disclosure. As show in FIG. 8, the preamble group A indicates a configuration C0 of a BWP type BWP_T0 and a configuration C2 of a BWP type BWP_T1 and the preamble group B indicates a configuration C1 of the BWP type BWP_T0 and a configuration C3 of the BWP type BWP_T1. Furthermore, DMRS sequences with indexes 0 and 1 (i.e. DMRS sequences #0 and #1) respectively indicate the configuration C0 of a BWP type BWP_T0 and the configuration C2 of a BWP type BWP_T1 indicated by the preamble group A and DMRS sequences with indexes 2 and 3 (i.e. DMRS sequences #2 and #3) respectively indicate the configuration C1 of a BWP type BWP_T0 and the configuration C3 of a BWP type BWP_T1 indicated by the preamble group B. In FIG. 8, the preamble groups A and B are associated to different DMRS sequences.

In an embodiment, the configuration of transmitting the payload of the message MsgA is indicated by only the DMRS (e.g. the DMRS sequence and/or the DMRS port) of the PUSCH of the message MsgA. For example, a DMRS sequence set may indicate a configuration of a BWP type and another DMRS sequence set may indicate another configuration of another BWP type, wherein each DMRS sequence set comprise at least one DMRS sequence and the DMRS sequences in the DMRS sequence set do not overlap. FIG. 9 shows configurations indicated by the preamble groups and the DMRS sequence sets according to an embodiment of the present disclosure. In FIG. 9, there is only a preamble group A associating with a configuration C0 of the BWP type BWP_T0 and a configuration C1 of the BWP type BWP_T1. In addition, a DMRS set comprising DMRS sequences with indexes 0 and 1 (i.e. DMRS sequences #0 and #1) indicates the configuration C0 of the BWP type BWP_T0 and another DMRS set comprising DMRS sequences with indexes 2 and 3 (i.e. DMRS sequences #2 and #3) indicates the configuration C1 of the BWP type BWP_T1. In this embodiment, the receiver determines the configuration of transmitting the payload of the message MsgA base on indications of the DMRS sequence of the PUSCH of the message MsgA. When receiving the message MsgA, the receiver determines the DMRS set to which the DMRS sequence of the PUSCH (e.g. the payload) belongs and accordingly determines the configuration of transmitting the payload of the message MsgA. For example, the receiver may determine the index of the DMRS sequence is 3 (i.e. DMRS sequence #3) and determines the configuration indicated by the DMRS sequence #3 is the configuration C1 of the BWP type BWP_T1. Thus, the receiver decodes the payload with the configuration C1 of the BWP type BWP_T1.

In an embodiment, the DMRS is generated based on at least one of the preamble of the message MsgA or the configuration of transmitting the payload. Therefore, the DMRS is able to be associated with the preamble group and to indicate the configuration of transmitting the payload.

For example, a pseudo-random sequence generator of the DMRS is initiated by a DMRS initialization sequence c _init which may be expressed as:

where

relates to (e.g. is) the number of symbols in a slot,

relates to (e.g. is) a slot number (e.g. index) within a frame, l relates to (e.g. is) a symbol number (e.g. index) within a slot. In addition, n _SCID is 0 or one of {0, 1} which is indicated by a DMRS field in downlink control information (DCI) associated with a transmission of the PUSCH (e.g. the payload) or by at least one higher layer parameter, if present, and

may be determined based on (e.g. configured by) at least one higher layer parameter or to be

which is related to the number of physical cell identities in the wireless network. In an embodiment, at least one of

or n _SCID is further determined based on at least one of the preamble or the BWP type corresponding to the configuration of transmitting the payload.

In an embodiment,

of the DMRS initialization sequence c _init is determined based on the BWP type associated with the configuration of transmitting the payload. In this embodiment, the n _SCID may be set to be one of {0, 1} . For example, the n _SCID may be 0. FIG. 10 shows a table of parameters of DMRS initialization sequence c _init according to an embodiment of the present disclosure. In this embodiment, the value of

may be determined based on the at least one higher layer parameter or to be

Furthermore, the

is further determined based on the BWP type associated to the configuration of transmitting the payload of the message MsgA. When the

is associated to the BWP type BWP_T0, the value of

is unchanged. When the

is associated with the BWP type BWP_T1, the value of

is shifted by an offset (i.e. changing to be

) , wherein the offset is a positive integer. In an example, the offset is

wherein

is a floor function of outputting a maximum integer smaller than the input X. Because the DMRS initialization sequence c _init becomes different when the value of

changes, the DMRS sequences associated with the BWP types BWP_T0 and BWP_T1 are different. Therefore, the configurations associated with the BWP types BWP_T0 and BWP_T1 can be differentiated based on the DMRS initialization sequences c _init generated by

with different values. For example, based on the table shown in FIG. 10, the relationships among configurations, preamble groups and DMRS sequences may be those shown in FIG. 6. Since the

associated with the BWP type BWP_T0 is unchanged, the configurations C0 and C1 of the BWP type BWP_T0 are indicated by the same DMRS sequence (i.e. the DMRS sequence #0) . Similarly, the configurations C2 and C3 of the BWP type BWP_T1 are indicated by the same DMRS sequence (i.e. the DMRS sequence #1) because the

associated with the BWP type BWP_T1 keeps the same as shown in FIG. 10.

In an embodiment, n _SCID is determined based on at least one of the preamble or the BWP corresponding to the configuration of transmitting the payload.

In an embodiment, n _SCID of the DMRS initialization sequence c _init is determined based on the BWP type associated with the configuration of transmitting the payload. In this embodiment,

may be determined based on at least one higher layer parameter or to be

related to the number of physical cell identities in the wireless network. FIG. 11 shows a table of parameters of DMRS initialization sequence according to an embodiment of the present disclosure. In FIG. 11, n _SCID is one of {0, 1} based on the associated BWP type. Note that,

is an XOR function. When the n _SCID is 0, the value of

is 1; and when the n _SCID is 1, the value of

is 0. As shown in FIG. 11, when the BWP type associated with the configuration of transmitting the payload is the BWP type BWP_T0, the value of n _SCID is unchanged. When the BWP type associated with the configuration of transmitting the payload is the BWP type BWP_T1, the value of n _SCID is changed to be the value of

Thus, the BWS type associated with the configuration of transmitting the payload is able to be differentiated based on the DMRS sequence.

Based on the table shown in FIG. 11, the relationships among configurations, preamble groups and DMRS sequences may be those shown in FIG. 6. Since the n _SCID associated with the BWP type BWP_T0 is unchanged, the configurations C0 and C1 of the BWP type BWP_T0 are indicated by the same DMRS sequence (i.e. the DMRS sequence #0) . Similarly, the configurations C2 and C3 of the BWP type BWP_T1 are indicated by the same DMRS sequence (i.e. the DMRS sequence #1) because the n _SCID associated with the BWP type BWP_T1 keeps the same as shown in FIG. 11.

In an embodiment, n _SCID is determined based on the preamble group to which the preamble of the message MsgA belongs and

of the DMRS initialization sequence is determined based on the BWP type associated with the configuration of transmitting the payload. FIG. 12 shows a table of parameters of DMRS initialization sequence according to an embodiment of the present disclosure. As shown in FIG. 12, when the preamble belongs the preamble group A, n _SCID can be expressed as:

n _SCID=mod (preamble_index, 2)

where mod (x, y) is a function of acquiring a reminder of dividing x by y, preamble_index is the index of the preamble. That is, n _SCID is the reminder of dividing the index of the preamble by 2 (i.e. n _SCID is one of {0, 1} ) . When the preamble belongs the preamble group B, n _SCID can be expressed as:

where

is the XOR function. When the value of the reminder of dividing the index of the preamble by 2 is 0, n _SCID is 1 if the preamble belongs the preamble group B. When the value of the reminder of dividing the index of the preamble by 2 is 1, n _SCID is 0 if the preamble belongs the preamble group B. Since the n _SCID is further determined based on the preamble group to which the preamble of the message MsgA belongs, the configurations associated with the same preamble group can be differentiated based on the DMRS sequence.

On the other hand, when the BWP type of the configuration configured for transmitting the payload is the BWP type BWP_T0, the value of

is

related to the number of physical cell identities in the network. When the BWP type of the configuration configured for transmitting the payload is the BWP type BWP_T1, the value of

is a sum of

and an offset. Because

of the DMRS initialization sequence is further determined based on the BWP type associated with the configuration of transmitting the payload, the configuration associated to the same BWP type may be distinguished by the DMRS sequence.

For example, the configurations indicated by the preamble groups and the DMRS sequences generated based on the table shown in FIG. 12 may be those shown in FIG. 8. Since the parameters of the DMRS initialization sequence change with the preamble group to which the preamble of the message MsgA belongs and/or the BWP type associated with the configuration of transmitting the payload of the message MsgA, the DMRS sequences #0, #1, #2 and #3 shown in FIG. 8 are different from each others. In other words, the configuration of transmitting the payload may be indicated (e.g. determined) only based on the DMRS sequence in the embodiment shown in FIG. 8 and/or FIG. 12.

In an embodiment,

of the DMRS initialization sequence c _init is further determined based on the preamble group to which the preamble of the message MsgA belongs. The details of determining

of the DMRS initialization sequence based on the preamble group may be referred to the embodiment shown in FIG. 10, thus are not narrated herein for brevity.

In an embodiment, the preamble groups may be respectively associated with different DMRS ports. Thus, the preamble groups may be differentiated based on the DMRS port of the DMRS sequence for the PUSCH of the message MsgA .

In an embodiment, a transform precoding is enabled. In this embodiment, a DMRS sequence group index u is determined based on at least one of the BWP of the configuration of transmitting the payload (e.g. based on the index of the BWP) , the preamble group to which the preamble belongs (e.g. the index of the preamble group) , or the preamble (e.g. the index of the preamble) . For example, the DMRS sequence group index

where

is determined based on at least one of the index of the BWP, the index of the preamble group or the index of the preamble.

In an embodiment of new radio unlicensed spectrum, the configuration of transmitting the payload in the message MsgA may be indicated by a PUSCH interlace. For example, a PUSCH interlace with index 0 (i.e. PUSCH interlace #0) indicates a configuration C0 of a BWP type BWP_T0 and another PUSCH interlace with index 1 (i.e. PUSCH interlace #1) indicates a configuration C1 of a BWP type BWP_T1. Based on determining the PUSCH interlace associated with the payload is the PUSCH interlace #0 or #1, the receiver is able to determine the configuration of transmitting the payload is the configuration C0 of a BWP type BWP_T0 or the configuration C1 of a BWP type BWP_T1.

In an embodiment of new radio unlicensed spectrum, the configuration of transmitting the payload in the message MsgA may be indicated by a set of consecutive PUSCH interlaces.

In an embodiment, the configuration of transmitting the payload in the message MsgA may be indicated by at least one of the preamble of the message MsgA, the DMRS sequence of the payload, the DMRS port of the payload, or the PUSCH interlace. For example, the configuration of transmitting the payload in the message MsgA may be indicated by the preamble and the PUSCH interlace of the payload.

In an embodiment, the wireless network may support more than 2 BWP types (e.g. the initial BWP, the active BWP and the default BWP) . FIG. 13 shows configurations indicated by the preamble groups and the DMRS sequence sets according to an embodiment of the present disclosure. In FIG. 13, there is only a preamble group A indicates a configuration C0 of the BWP type BWP_T0, a configuration C1 of the BWP type BWP_T1 and a configuration C2 of the BWP type BWP_T2. In addition, the configuration C0 of the BWP type BWP_T0, the configuration C1 of the BWP type BWP_T1 and the configuration C2 of the BWP type BWP_T2 are respectively indicated by DMRS sequences with

indexes

0, 1 and 2 (i.e. DMRS sequences #0, #1 and #2) . Therefore, the configuration C0 of the BWP type BWP_T0, the configuration C1 of the BWP type BWP_T1 and the configuration C2 of the BWP type BWP_T2 can be differentiated based on the corresponded DMRS sequence. For example, the DMRS initialization sequence c _init of the DMRS sequence is generated based on associated BWP type. Thus, the receiver is able to determine the configuration of transmitting the payload based on the DMRS sequence of the payload.

While various embodiments of the present disclosure have been described above, it should be understood that they have been presented by way of example only, and not by way of limitation. Likewise, the various diagrams may depict an example architectural or configuration, which are provided to enable persons of ordinary skill in the art to understand exemplary features and functions of the present disclosure. Such persons would understand, however, that the present disclosure is not restricted to the illustrated example architectures or configurations, but can be implemented using a variety of alternative architectures and configurations. Additionally, as would be understood by persons of ordinary skill in the art, one or more features of one embodiment can be combined with one or more features of another embodiment described herein. Thus, the breadth and scope of the present disclosure should not be limited by any of the above-described exemplary embodiments.

It is also understood that any reference to an element herein using a designation such as "first, " "second, " and so forth does not generally limit the quantity or order of those elements. Rather, these designations can be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, a reference to first and second elements does not mean that only two elements can be employed, or that the first element must precede the second element in some manner.

Additionally, a person having ordinary skill in the art would understand that information and signals can be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits and symbols, for example, which may be referenced in the above description can be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

A skilled person would further appreciate that any of the various illustrative logical blocks, units, processors, means, circuits, methods and functions described in connection with the aspects disclosed herein can be implemented by electronic hardware (e.g., a digital implementation, an analog implementation, or a combination of the two) , firmware, various forms of program or design code incorporating instructions (which can be referred to herein, for convenience, as "software" or a "software unit” ) , or any combination of these techniques.

To clearly illustrate this interchangeability of hardware, firmware and software, various illustrative components, blocks, units, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware, firmware or software, or a combination of these techniques, depends upon the particular application and design constraints imposed on the overall system. Skilled artisans can implement the described functionality in various ways for each particular application, but such implementation decisions do not cause a departure from the scope of the present disclosure. In accordance with various embodiments, a processor, device, component, circuit, structure, machine, unit, etc. can be configured to perform one or more of the functions described herein. The term “configured to” or “configured for” as used herein with respect to a specified operation or function refers to a processor, device, component, circuit, structure, machine, unit, etc. that is physically constructed, programmed and/or arranged to perform the specified operation or function.

Furthermore, a skilled person would understand that various illustrative logical blocks, units, devices, components and circuits described herein can be implemented within or performed by an integrated circuit (IC) that can include 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, or any combination thereof. The logical blocks, units, and circuits can further include antennas and/or transceivers to communicate with various components within the network or within the device. A general purpose processor can be a microprocessor, but in the alternative, the processor can be any conventional processor, controller, or state machine. A processor can 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 suitable configuration to perform the functions described herein. If implemented in software, the functions can be stored as one or more instructions or code on a computer-readable medium. Thus, the steps of a method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium.

Computer-readable media includes both computer storage media and communication media including any medium that can be enabled to transfer a computer program or code from one place to another. A storage media can be any available media that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer.

In this document, the term "unit" as used herein, refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. Additionally, for purpose of discussion, the various units are described as discrete units; however, as would be apparent to one of ordinary skill in the art, two or more units may be combined to form a single unit that performs the associated functions according embodiments of the present disclosure.

Additionally, memory or other storage, as well as communication components, may be employed in embodiments of the present disclosure. It will be appreciated that, for clarity purposes, the above description has described embodiments of the present disclosure with reference to different functional units and processors. However, it will be apparent that any suitable distribution of functionality between different functional units, processing logic elements or domains may be used without detracting from the present disclosure. For example, functionality illustrated to be performed by separate processing logic elements, or controllers, may be performed by the same processing logic element, or controller. Hence, references to specific functional units are only references to a suitable means for providing the described functionality, rather than indicative of a strict logical or physical structure or organization.

Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the general principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein, but is to be accorded the widest scope consistent with the novel features and principles disclosed herein, as recited in the claims below.

Claims

A wireless communication method for use in a wireless terminal, comprising:

transmitting, to a wireless network node, a message comprising a preamble and a payload for a random access procedure,

wherein the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH, of the message indicate a configuration of transmitting the payload.
The wireless communication method of claim 1, wherein the configuration is indicated by a preamble index of the preamble.
The wireless communication method of claim 1 or 2, wherein the configuration is indicated by a preamble group comprising the preamble.
The wireless communication method of any of claims 1 to 3, wherein the DMRS is determined based on at least one of the preamble or a bandwidth part, BWP, corresponding to the configuration.
The wireless communication method of claim 4, wherein the DMRS is determined based on at least one of the preamble or an index of the BWP.
The wireless communication method of claim 4 or 5, wherein the DMRS is determined based on at least one of the preamble or a type of the BWP.
The wireless communication method of claim 6, wherein the type of the BWP includes an initial BWP, an active BWP or a default BWP.
The wireless communication method of any of claims 6 to 9, wherein a pseudo-random sequence generator of the DMRS is initiated by:

wherein,
relates to the number of symbols of a slot,
relates to a slot number within a frame, l is the symbol number within a slot, n _SCID is 0 or one of {0, 1} which is indicated by a DMRS field in downlink control information (DCI) associated with a transmission of the PUSCH or by at least one higher layer parameter, and
is determined based on at least one higher layer parameter or be
which is related to the number of physical cell identities,

wherein at least one of
or n _SCID is further determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 8, wherein n _SCID is determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 8, wherein
is determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 8, wherein n _SCID is 0 and
is determined based on the BWP corresponding to the configuration.
The wireless communication of claim 8, wherein n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 8, wherein n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration and
is determined based on another one of the preamble or the BWP corresponding to the configuration.
The wireless communication method of any of claims 1 to 13, wherein the configuration of transmitting the payload is indicated by the preamble, the DMRS of the PUSCH and at least one physical uplink shared channel interlace.
The wireless communication method of any of claims 1 to 14, wherein the configuration comprises at least one of resource, a modulation coding scheme or demodulation reference signal information.
A wireless communication method for use in a wireless network node, comprising:

receiving, from a wireless terminal, a message comprising a preamble and a payload for a random access procedure, and

decoding the payload based on a configuration indicated by the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH of the message.
The wireless communication method of claim 16, wherein the configuration is indicated by a preamble index of the preamble.
The wireless communication method of claim 16 or 17, wherein the configuration is indicated by a preamble group comprising the preamble.
The wireless communication method of any of claims 16 to 18, wherein the DMRS is determined based on at least one of the preamble or a bandwidth part, BWP, corresponding to the configuration.
The wireless communication method of claim 19, wherein the DMRS is determined based on at least one of the preamble or an index of the BWP.
The wireless communication method of claim 19 or 20, wherein the DMRS is determined based on at least one of the preamble or a type of the BWP.
The wireless communication method of claim 21, wherein the type of the BWP includes an initial BWP, an active BWP or a default BWP.
The wireless communication method of any of claims 19 to 22, wherein a pseudo-random sequence generator of the DMRS is initiated by:

wherein,
relates to the number symbols of a slot,
relates to a slot number within a frame, l is a symbol number within a slot, n _SCID is 0 or one of {0, 1} which is indicated by a DMRS field in downlink control information (DCI) associated with a transmission of the PUSCH or by at least one higher layer parameter, and
is determined based on at least one higher layer parameter or be
which is related to the number of physical cell identities,

wherein at least one of
or n _SCID is further determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 23, wherein n _SCID is determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 23, wherein
is determined based on at least one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 23, wherein n _SCID is 0 and
is determined based on the BWP corresponding to the configuration.
The wireless communication of claim 23, wherein n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration.
The wireless communication of claim 23, wherein n _SCID is one of 0 and 1 based on one of the preamble or the BWP corresponding to the configuration and
is determined based on another one of the preamble or the BWP corresponding to the configuration.
The wireless communication method of any of claims 16 to 28, wherein the configuration of transmitting the payload is further indicated by the preamble, the DMRS of the PUSCH and at least one physical uplink shared channel interlace.
The wireless communication method of any of claims 16 to 29, wherein the configuration comprises at least one of resource, a modulation coding scheme or demodulation reference signal information.
A wireless terminal, comprising a communication unit configured to transmit, to a wireless network node, a comprising a preamble and a payload for a random access procedure, wherein the preamble and a demodulation reference signal, DMRS for a physical uplink shared channel, PUSCH, of the message indicate a configuration of transmitting the payload.
The wireless terminal of claim 31, further comprising a processor configured to perform the wireless communication method of any of claims 2 to 15.
A wireless network node, comprising:

a communication unit, configured to receive, from a wireless terminal, a message comprising a preamble and a payload for a random access procedure, and

a processor, configured to decode the payload with a configuration indicated by the preamble and a demodulation reference signal, DMRS, for a physical uplink shared channel, PUSCH of the message.
The wireless network node of claim 33, wherein the processor is further configured to perform the wireless communication method of any of claims 16 to 30.
A computer program product comprising a computer-readable program medium code stored thereupon, the code, when executed by a processor, causing the processor to implement a wireless communication method recited in any of claims 1 to 30.