Patent Description:
In the 5th Generation (<NUM>) New Radio (NR) mobile networks, before a user equipment (UE) can send data to a base station (BS), the UE is required to obtain uplink synchronization and downlink synchronization with the BS. The uplink timing synchronization can be achieved by performing a random access procedure. To meet the demand for faster and efficient communications, the random access procedure is to be enhanced.

<CIT>, <CIT>, <CIT>, 3GPP Draft R2-<NUM> and <CIT> are related prior art documents. In particular <CIT> teaches a base station which broadcasts threshold values for enabling a plurality of wireless devices (UE) to select a random access preamble. The base station then sends to a particular UE modified threshold values overriding the broadcast values via dedicated signaling enabling that particular wireless device to perform a CBRA procedure.

" Such an example network <NUM> includes a base station <NUM> (hereinafter "BS <NUM>") and a user equipment device <NUM> (hereinafter "UE <NUM>") that can communicate with each other via a communication link <NUM> (e.g., a wireless communication channel), and a cluster of cells <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> overlaying a geographical area <NUM>.

In the present disclosure, the BS <NUM> and UE <NUM> are respectively described herein as non-limiting examples of "communication node" (or "wireless communication node") and "communication device" (or "wireless communication device") generally, which can practice the methods disclosed herein. Such communication nodes and devices may be capable of wireless and/or wired communications, in accordance with various embodiments of the present solution.

<FIG> illustrates a block diagram of an example wireless communication system <NUM> for transmitting and receiving wireless communication signals, e.g., OFDM/OFDMA signals, in accordance with some embodiments of the present solution. The system <NUM> may include components and elements configured to support known or conventional operating features that need not be described in detail herein. In one illustrative embodiment, system <NUM> can be used to communicate (e.g., transmit and receive) data symbols in a wireless communication environment such as the wireless communication environment <NUM> of <FIG>, as described above.

The operations of the two transceiver modules <NUM> and <NUM> can be coordinated in time such that the uplink receiver circuitry is coupled to the uplink antenna <NUM> for reception of transmissions over the wireless transmission link <NUM> at the same time that the downlink transmitter is coupled to the downlink antenna <NUM>.

In accordance with various embodiments, the BS <NUM> may be a next generation nodeB (gNodeB or gNB), an evolved node B (eNB), a serving eNB, a target eNB, a femto station, a pico station, or a Transmission Reception Point (TRP), for example.

Furthermore, the steps of a process, method, or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in firmware, in a software module executed by processor modules <NUM> and <NUM>, respectively, or in any practical combination thereof.

An example <NUM>-step random access procedure includes at least one of a transmission of one or more of a message A (msgA) and a transmission of one or more of a message B (msgB). In some embodiments of the present disclosure, the network configures parameters for the one or more msgA transmissions by system information (SI). In some embodiments, the network configures the parameters, such as an uplink transmission resource allocation, a modulation and coding scheme (MCS), and a transport block size (TBS), among others, in advance. The configuration information (e.g. the parameters) can be conveyed in the SI. In some embodiments, an information element (IE) contains the parameters.

The UE can transmit a number of bits as uplink (UL) data transmission. The number of bits can be <NUM>, <NUM>, <NUM>, or <NUM>, among others. Thus, the required resource can be different. Since the resource is preserved by SI (e.g. it is unchanged during a period of time), it may be waste of resources if a large block of resources was still preserved when the UE changed the number of bits from <NUM> bits to <NUM> bits. In contrast, the preserved resource may be insufficient if a larger size payload was requested. Thus, flexible resource allocation mechanism is needed in order to improve the utility and/or efficiency of resource usage.

<FIG> illustrates an example <NUM>-step random access procedure <NUM>, in accordance with some embodiments of the present disclosure. The <NUM>-step random access channel (RACH) is a way to reduce the procedure for lower random access (RA) latency and downlink signaling overhead. In some embodiments, it finishes the random access procedure by a <NUM>-step procedure (e.g. two transmissions including a msgA uplink transmission and a msgB downlink transmission). The <NUM>-step RA procedure and corresponding <NUM>-step RACH can be used for several purposes, including for initial access when establishing a radio link (e.g. moving from radio resource control IDLE (RRC_IDLE) or RRC_INACTIVE to RRC_CONNECTED), for handover when uplink synchronization needs to be established to the new cell, or to establish uplink synchronization if uplink or downlink data arrives when the terminal is in RRC_CONNECTED and the uplink is not synchronized.

Referring to <FIG>, the <NUM>-step random access procedure <NUM> is performed between a BS <NUM> (e.g., a gNB, a gNodeB, the BS <NUM>, and/or the BS <NUM>) and a UE <NUM> (e.g. a device, a mobile device, the UE <NUM>, and/or the UE <NUM>). In some embodiments, before the <NUM>-step random access procedure <NUM>, at Step <NUM> (<NUM>), the BS <NUM> transmits a downlink (DL) synchronization (synch) to the UE <NUM>. In some embodiments, the DL synch transmission is a cell search, a downlink synchronization, and/or a system information block, among others. In some embodiments, the DL synch transmission includes one or more transmissions of the IEs for configuring the parameters associated with the transmission of the one or more of the msgA.

In some embodiments, at Step <NUM> (<NUM>) of the <NUM>-step random access procedure <NUM>, the UE <NUM> transmits the one or more of the msgA. In some embodiments, the preamble <NUM> (as shown in <FIG>) is optional. In some embodiments, the time-frequency resource on which the one or more of the msgA are transmitted is the physical random-access channel (PRACH), the uplink shared channel (ULSCH), or the physical uplink shared channel (PUSCH).

<FIG> illustrates an example message during a random access procedure, in accordance with some embodiments of the present disclosure. Referring now to <FIG>, a msgA <NUM> includes a preamble <NUM> and a data payload <NUM> to a BS <NUM> for access to the BS <NUM>. In some embodiments, the payload <NUM> is optional.

Referring back to <FIG>, at step <NUM> (<NUM>), the BS <NUM> transmits one or more of the msgB as a response to the one or more of the msgA (e.g. the msgA <NUM>) to the UE <NUM>. In some embodiments, the time-frequency resource on which the msgB is transmitted is the downlink shared channel (DLSCH) or the physical downlink control channel (PDCCH). In some embodiments, the UE <NUM> monitors L1/L2 control channels for the one or more msgB transmissions within a predetermined time window. Responsive to not receiving at least one of the one or more msgB transmissions within the time window, the attempt may be declared as failed and the procedure will repeat.

In some embodiments, a wireless communication node (e.g. the BS <NUM>) transmits, to a plurality of wireless devices (e.g. multiple UEs <NUM>), a first IE that includes a plurality of parameters. In some embodiments, the plurality of parameters is configured for the plurality of wireless communication devices to perform respective random access procedures. In some embodiments, the wireless communication node transmits, to a wireless device (e.g. the UE <NUM>), a second IE that includes a subset of the plurality of parameters. In some embodiments, the subset of parameters is configured for the wireless device to perform a random access procedure. Performing the random access procedure can include initiating and/or updating the random access procedure (e.g. initiating or updating the parameters that configure the msgA and/or msgB transmission). The random access procedure may include the <NUM>-step random access procedure.

In genereal a RACH-ConfigCommon IE is used to specify the cell specific random-access parameters, and a RACH-ConfigDedicated IE is used to specify dedicated random access parameters. The RACH-ConfigDedicated IE can contain parameters such as contention free random access (CFRA) occasions and CFRA synchronization signal block (SSB) resources. In some embodiments of the present disclosure, for the msgA payload transmission, a <NUM>-stepRACH-ConfigCommon IE is used to specify the cell specific random-access parameters and a <NUM>-stepRACH-ConfigDedicated IE is used to specify dedicated random access parameters.

In some embodiments, the plurality of parameters in the first IE (e.g. the <NUM>-stepRACH-ConfigCommon IE) is further commonly configured for each of the plurality of wireless communication devices to transmit one or more messages (e.g. the one or more of the msgA) to the wireless communication node in the random access procedure. The one or more messages can include a preamble and a payload. The BS <NUM> can transmit (e.g., broadcast) the first IE to all of the UEs in a cell defined by the BS <NUM>. In some embodiments, the subset of parameters in the second IE (e.g. the <NUM>-stepRACH-ConfigDedicated IE) is further dedicatedly configured for the wireless communication device to transmit the one or more messages to the wireless communication node in the random access procedure. The BS <NUM> can transmit the second IE to a specific UE. A PUSCH occasion can be configured for the UEs to transmit information (e.g.,UE_ID, data, UCI, CSI, etc.) over a msgA PUSCH. The PUSCH occasion is herein referred to as a PO.

In some embodiments of the present disclosure, for the one or more of the msgA payload transmission, a <NUM>-stepRACH-ConfigCommon IE is used to specify the cell specific random-access parameters and a <NUM>-stepRACH-ConfigDedicated IE is used to specify dedicated random access parameters. In one embodiment, the <NUM>-stepRACH-ConfigCommon IE contains at least one of the following parameters: a number of configurations; a modulation coding scheme (MCS); a transport block size (TBS); a physical uplink shared channel (PUSCH) mapping type; a number of frequency division multiplexed (FDMed) PUSCH occasions (POs); a number of physical resource blocks (PRBs) per PO; a frequency starting point; a number of demodulation reference signal (DMRS) symbols/ports/sequences per PO; a bandwidth of a PRB-level guard band or duration of a guard time; a periodicity of a msgA PUSCH configuration period; Offset(s) (e.g., symbol level and/or slot level, among others); a starting symbol and a number of time-domain POs in a slot for a msgA transmission; a number of symbols per PO; a number of time division multiplexed (TDMed) POs; and a redundancy version. In some embodiments, the redundancy version is a field that indicates a redundancy version of a code word (e.g. for turbo encoding).

In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains the MCS. In one embodiment, the MCS is defined to inform a MCS index, a modulation order, a code rate. In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains the TBS. In one embodiment, the TBS is defined to inform TBS information. The TBS information can include the size, whether the TBS into multiple codeblocks, and the number and the size of the multiple codeblocks. In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains a "MCS and TBS" parameter. In one embodiment, the "TBS and MCS" parameter is defined to inform the TBS information and the MCS index. In some embodiments, the <NUM>-stepRACH-ConfigDedicated IE contains one or more of the parameters contained in the <NUM>-stepRACH-ConfigCommon IE. The <NUM>-stepRACH-ConfigDedicated IE can be used to overwrite, replace, encode, decode, embed, or otherwise update the configurations that were configured by the parameters of the <NUM>-stepRACH-ConfigCommon IE.

In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains the number of PRBs per PO, common resource blocks (CRBs) per PO, and/or virtual resource blocks (VRBs) per PO. In one embodiment, the number of PRBs per PO is defined to inform the number of PRBs per PO for the POs configured by a configuration. In one embodiment, the number of PRBs per PO is defined to inform the max number of PRBs per PO among multiple UEs. In some embodiments, the <NUM>-stepRACH-ConfigDedicated IE contains a mapping from the number of VRBs per PO to the number of PRBs per PO.

<FIG> illustrates an example mapping <NUM> between a preamble and one or more POs, in accordance with some embodiments of the present disclosure. Referring now to <FIG>, in one embodiment, the UE <NUM> is configured to transmit, as at least a portion of the msgA, a contention based random access (CBRA) preamble <NUM> (e.g. the preamble <NUM>) and a CBRA payload (e.g. the data payload <NUM>). In some embodiments, one or more POs can be used to transmit the CBRA payload. In one embodiment, each of the one or more POs is configured by one of three configurations (e.g. PO <NUM> is configured by configuration <NUM>, PO <NUM> is configured by configuration <NUM>, and PO <NUM> is configured by the configuration <NUM>). In some embodiments, the UE <NUM> selects one or more of the POs <NUM>-<NUM> to transmit the CBRA payload. The selected one or more POs are mapped, linked, or otherwise coupled to the CBRA preamble <NUM>. In one embodiment, each of the configurations <NUM>-<NUM> is associated with a respective combination of the parameters included in the <NUM>-stepRACH-ConfigCommon IE (e.g. the first IE). In one embodiment, one of the configurations (e.g., configuration <NUM>) is associated with a combination of the parameters included in the <NUM>-stepRACH-ConfigDedicated IE (e.g. the second IE). The parameters included in the <NUM>-stepRACH-ConfigDedicated IE can be a subset of the parameters included in the <NUM>-stepRACH-ConfigCommon IE, but with different values. Thus, the <NUM>-stepRACH-ConfigDedicated IE can be used to replace, overwrite, encode, decode, embed, or otherwise update some parameters initially configured by the <NUM>-stepRACH-ConfigCommon IE.

<FIG> illustrates an example mapping <NUM> between a preamble and one or more POs, in accordance with some embodiments of the present disclosure. In some embodiments, the mapping <NUM> is same as the mapping <NUM> except for the differences described herein. Referring now to <FIG>, in some embodiments, each of the one or more POs is configured by one of four configurations (e.g. the POs <NUM>-<NUM> are configured by the configurations <NUM>-<NUM>, respectively, and PO <NUM> is configured by the configuration <NUM>). In one embodiment, each configuration <NUM>-<NUM> is associated with a respective combination of the parameters included in the <NUM>-stepRACH-ConfigCommon IE. Two of the configurations (e.g., configuration <NUM>-<NUM>) are associated with a combination of the parameters included in the <NUM>-stepRACH-ConfigDedicated IE (e.g. the second IE), in one embodiment.

<FIG> illustrates an example mapping <NUM> between a preamble and one or more POs, in accordance with some embodiments of the present disclosure. In some embodiments, the mapping <NUM> is same as the mapping <NUM> except for the differences described herein. Referring now to <FIG>, in some embodiments, each of the one or more POs is configured by one of two configurations (e.g. the POs <NUM>-<NUM> are configured by the configurations <NUM>-<NUM>, respectively). In one embodiment, each configuration <NUM>-<NUM> is associated with a respective combination of the parameters included in the <NUM>-stepRACH-ConfigCommon IE. In one embodiment, one of the configurations (e.g., configuration <NUM>) is associated with a combination of the parameters included in the <NUM>-stepRACH-ConfigDedicated IE (e.g. the second IE).

In one embodiment, a first configuration is designed for radio resource control (RRC) idle/inactive state UE transmission and a second configuration is designed for RRC connected state UE transmission. In one embodiment, each group of POs (e.g. the POs <NUM>-<NUM>) configured by each configuration is FDMed. In one embodiment, each group of POs configured by each configuration is time-domain aligned. For example, a plurality of resources (e.g. the POs <NUM>-<NUM>) assigned for transmitting the one or more of msgA, or a portion thereof, is multiplexed (e.g. the POs <NUM>-<NUM> are multiplexed) in a frequency-domain and aligned (e.g. the POs <NUM>-<NUM>-<NUM> are aligned with each other) in a time-domain.

In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains at least one of the TBS, the MCS, the number of PRBs per PO, and the bandwidth of the PRB-level guard band. In one embodiment, the <NUM>-stepRACH-ConfigDedicated IE contains the bandwidth of the PRB-level guard band. In one embodiment, the bandwidth of the PRB-level guard band is defined to inform a guard band between adjacent POs in the frequency-domain.

<FIG> illustrates an example mapping <NUM> between a preamble and one or more POs, in accordance with some embodiments of the present disclosure. In some embodiments, the mapping <NUM> is same as the mapping <NUM> except for the differences described herein. Referring now to <FIG>, in one embodiment, the POs <NUM> and <NUM> are totally overlapped in frequency-domain and time-domain. For example, the plurality of resources (e.g. the POs <NUM> and <NUM>) assigned for transmitting the one or more of msgA, or a portion thereof, is overlapped (e.g. the POs <NUM> and <NUM> overlap each other) in both the frequency-domain and the time-domain. In some embodiments, more than two POs overlap. In some embodiments, the subset of parameters in the second information element, and/or the plurality of parameters in the first information element, is further configured to assign, map, select, or otherwise configure the plurality of resources for transmitting the one or more of msgA (e.g. that are multiplexed or overlapped) to the wireless communication node in the random access procedure.

<FIG> is a flow diagram illustrating an example process <NUM> for configuring a random access procedure, in accordance with some embodiments of the present disclosure. In some embodiments, the process <NUM> can be performed by a wireless communication node (e.g., BS <NUM>). Additional, fewer, or different operations may be performed in the process <NUM> depending on the embodiment. At operation <NUM>, the wireless communication node transmits a first information element that includes a plurality of parameters. The plurality of parameters may be configured for a plurality of wireless communication devices to perform respective random access procedures. At operation <NUM>, the wireless communication node transmits a second information element that includes a subset of the plurality of parameters. The subset of parameters may be configured for one of the plurality of wireless communication devices to perform one of the random access procedures.

In some embodiments, the random access procedure includes a <NUM>-step random access procedure. In some embodiments, the plurality of parameters in the first information element is further commonly configured for each of the plurality of wireless communication devices to transmit one or more messages to the wireless communication node in the random access procedure. The one or more messages can include a preamble and a payload. In some embodiments, the subset of parameters in the second information element is further dedicatedly configured for the wireless communication device to transmit the one or more messages to the wireless communication node in the random access procedure.

In some embodiments, the subset of parameters in the second information element is further configured to update corresponding ones of the parameters in the first information element. In some embodiments, a communication apparatus comprising a processor is configured to implement the process <NUM>. In some embodiments, a computer readable medium having code stored thereon, to perform the process <NUM>.

<FIG> is a flow diagram illustrating an example process <NUM> for configuring a random access procedure, in accordance with some embodiments of the present disclosure. In some embodiments, the process <NUM> can be performed by a wireless communication device (e.g., UE <NUM>). Additional, fewer, or different operations may be performed in the process <NUM> depending on the embodiment. At operation <NUM>, the wireless communication device receives, from a wireless communication node, a first information element that includes a plurality of parameters. The plurality of parameters may be configured for a plurality of wireless communication devices to perform respective random access procedures. At operation <NUM>, the wireless communication device receives, from a wireless communication node, a second information element that includes a subset of the plurality of parameters. The subset of parameters may be configured for the wireless communication device to perform one of the random access procedures.

It should be understood that the value used for each case listed above is an example, and the mapping between the value and the case is not limited to the examples above. They are provided for illustrative purpose only and should not be regarded as limiting.

Claim 1:
A wireless communication method, comprising:
transmitting, by a wireless communication node, a first information element that includes a plurality of parameters, the plurality of parameters configured for a plurality of wireless communication devices to perform respective random access procedures; and
transmitting, by the wireless communication node, a second information element that includes a subset of the plurality of parameters, the subset of parameters configured for a wireless communication device of the plurality of wireless communication devices to perform one of the random access procedures,
wherein the plurality of parameters in the first information element is further commonly configured for each of the plurality of wireless communication devices to transmit one or more messages, that include a preamble and a payload, to the wireless communication node in the random access procedure,
wherein the subset of parameters in the second information element is further dedicatedly configured for the wireless communication device to transmit the one or more messages to the wireless communication node in the random access procedure, and
wherein the wireless communication node comprises a base station, and wherein each wireless communication device of the plurality of wireless communication devices comprises a user equipment.