Method and apparatus for random access procedure

Abstract

The embodiment of the invention provides a random access process method and device. A method at a user equipment (UE) includes selecting a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a criterion. The method also includes sending a first message to the base station, the first message including a random access channel (RACH) preamble on a random access channel (RACH) occasion and data on an uplink shared channel (USCH). The RACH preamble and the RACH occasion are selected based on a mapping of the SSB to the RACH preamble and the RACH occasion. The method also includes receiving a second message from the base station as a response to the first message.

Description

Divisional application This application is a divisional application of a patent application with application number 202080049868.4, application date June 30, 2020, entering the Chinese national phase on January 7, 2022, and the invention name is “Method and device for random access process”. Technical Field

[0001] Non-limiting and exemplary embodiments of the present disclosure relate generally to the field of communication technology, and particularly to methods and apparatus for random access procedures. Background Art

[0002] This section introduces various aspects that may help to better understand the present disclosure. Therefore, the statements in this section should be read in this light, and should not be understood as an admission about what is or is not in the prior art.

[0003] In a wireless communication system such as NR (New Radio), a UE needs a random access procedure such as a 4-step random access procedure to gain access to the communication system. Before initiating the random access procedure, the UE needs to go through an initial synchronization procedure. For example, the UE needs to detect synchronization signals (SS), such as the primary synchronization signal (PSS) and the secondary synchronization signal (SSS), etc. The UE then decodes the broadcasted system information. The next step is called a random access procedure.

[0004] In such Figure 1 In the 4-step random access process shown, the UE sends a PRACH (Physical Random Access Channel) preamble (msg1) in the uplink at step 102. The base station, such as a next generation NodeB (gNodeB or gNB), replies with a RAR (Random Access Response, msg2) at step 104. The RAR may carry the following information: temporary C-RNTI (Cell Radio Network Temporary Identity); timing advance value; and uplink granted resources. The UE then sends an RRC (Radio Resource Control) Connection Request message (msg3) on the Physical Uplink Shared Channel (PUSCH) at step 106. The RRC Connection Request message may contain the following information: UE identity and connection establishment cause. The UE sends the PUSCH (msg3) after receiving the timing advance command in the RAR to allow the timing accuracy within the cyclic prefix so that the PUSCH will be received. Without this timing advance, unless the system is applied in a cell with a very small distance between the UE and the base station, a very large CP (cyclic prefix) will be required to be able to demodulate and detect the PUSCH. The base station responds with a contention resolution message (msg4) to the UE at step 108. Since NR will also support larger cells that need to provide timing advance to the UE, a 4-step random access procedure is required for the random access procedure. Summary of the invention

[0005] This Summary is provided in a simplified form to introduce selected concepts that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0006] The 2-step RACH (Random Access Channel) work item has been approved at the 3rd Generation Partnership Project (3GPP) meeting. Figure 2 The 2-step random access procedure shown can complete the initial access in only 2 steps. Figure 2 As shown, at step 202, the UE sends a message A (msgA) including a PRACH preamble on a PRACH opportunity and higher layer data (such as an RRC connection request) that may have some small payload on a PUSCH. At step 204, the base station (e.g., gNB) sends a message B (msgB) (e.g., RAR) including one or more of a UE identifier allocation, timing advance information, and a contention resolution message.

[0007] In NR, the time and frequency resources on which the PRACH preamble is sent are defined as PRACH opportunities. PRACH opportunities may also be referred to as RACH opportunities, or RA opportunities, or RO for short. The RO used for transmission of the PRACH preamble in the 2-step random access procedure is called a 2-step RO, while the RO used for transmission of the PRACH preamble in the 4-step random access procedure is called a 4-step RO.

[0008] 3GPP's NR Release (Rel) 15 supports one-to-one, one-to-many, and many-to-one associations between synchronization signal blocks and PRACH opportunities. In addition, there can be a mapping between SSBs (synchronization signal and physical broadcast channel blocks) and PRACH preambles. In NR, SSBs can include PSS, SSS, and PBCH (physical broadcast channel). When the UE selects an available SSB beam, the PRACH opportunity associated with the SSB and a PRACH preamble from a set of one or more PRACH preambles mapped to the SSB will be selected for random access, and then when the gNB detects the PRACH preamble, based on the association, the SSB beam selected for the UE is known, so that the selected beam can be used to send signals to or receive signals from the UE.

[0009] In the recent NR RAN2 meeting, the following agreement has been made to support msgB multiplexing messages for multiple UEs transmitted in a single PDSCH (Physical Downlink Shared Channel). - For CCCH (Common Control Channel), for success or fallback RAR, MsgB can multiplex messages for multiple UEs. For further study (FFS), whether we can multiplex SRB (Signaling Radio Bearer) RRC messages for multiple UEs. - MsgB containing a successful RAR should not be multiplexed with the conventional 4-step RACH RAR in the same MAC (Media Access Control) PDU (Protocol Data Unit).

[0010] In the 2-step random access procedure, no agreement has been reached on SSB selection and reporting.

[0011] Although the 2-step random access procedure supports the merging of messages for multiple UEs in the same msgB, there are some concerns in the 2-step random access procedure. For example, one issue is when multiple SSBs are mapped to one RO, whether the msgB transmissions for these UEs correspond to different SSB beams, it is impossible to know which SSB beam should be used for the combined transmission of msgB. Another issue is that it has not been determined which RNTI (Radio Network Temporary Identifier) ​​and / or MCS (Modulation and Coding Scheme) should be used for such msgB transmissions, and monitoring needs to be determined.

[0012] In order to overcome or alleviate at least one of the above problems or other problems or to provide a useful solution, some embodiments of the present disclosure propose methods on how to group UEs in the same msgB PDSCH transmission. Some embodiments provide a solution for indicating SSB by UE. Some embodiments provide a solution for determining the beam to be used for combined msgB transmission. Some embodiments provide a solution for determining the RNTI to be used for combined msgB transmission / monitoring. Some embodiments provide a solution for determining the MCS to be used for combined msgB transmission.

[0013] In a first aspect of the present disclosure, a method at a user equipment (UE) is provided. The method includes sending a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The method also includes receiving a second message as a response to the first message.

[0014] In one embodiment, the at least one SSB having a signal measurement metric that satisfies the criteria includes a subset or set of all SSBs having signal measurement metrics that satisfy the criteria.

[0015] In one embodiment, the at least one SSB having a signal measurement metric that meets the criteria includes an SSB associated with a RACH opportunity.

[0016] In one embodiment, the at least one SSB having a signal measurement metric satisfying the criterion includes an SSB in the set of SSBs having a signal measurement metric satisfying the criterion excluding an SSB indicated by a RACH preamble and a RACH opportunity.

[0017] In one embodiment, at least one SSB is indicated using a list ordered by a signal measurement metric.

[0018] In one embodiment, at least one SSB is indicated by using a bitmap.

[0019] In one embodiment, the RACH preamble and RACH opportunity are selected based on a mapping of SSBs to RACH preambles and RACH opportunities.

[0020] In one embodiment, the RACH preamble and RACH opportunity are selected based on predefined rules.

[0021] In one embodiment, the RACH is a physical random access channel (PRACH), the USCH is a physical uplink shared channel (PUSCH), and the signal measurement metric is a reference signal received power (RSRP), or a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) based on downlink signal measurements.

[0022] In one embodiment, the criterion is that the signal measurement metric is greater than or not less than a threshold value.

[0023] In one embodiment, the second message may multiplex respective responses to respective first messages of the UE and at least one other UE.

[0024] In one embodiment, UEs with the same determined MCS are multiplexed in the second message; and / or UEs with a specific common SSB that satisfies a standard signal measurement metric are multiplexed in the second message; and / or UEs sending RACH preambles mapped to the same SSB are multiplexed in the second message; and / or UEs with the same downlink preferred beam are multiplexed in the second message.

[0025] In one embodiment, the beam used for the second message is one of: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0026] In one embodiment, the radio network temporary identifier (RNTI) used for the second message is one of: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0027] In one embodiment, when the at least one other UE and the UE send the first message on the same RACH opportunity, the common RNTI is calculated based on the same RACH opportunity, or the common RNTI is a group RNTI defined for the UE and at least one other UE; or the common RNTI is indicated in the corresponding first messages from the UE and at least one other UE.

[0028] In one embodiment, when the RNTI used for the second message is a UE-specific RNTI, the system frame number is included in the downlink control information to indicate whether the corresponding second message is for the UE. In one embodiment, the UE-specific RNTI is a random access RNTI (RA-RNTI).

[0029] In one embodiment, the modulation and coding scheme (MCS) used for the second message is one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0030] In a second aspect of the present disclosure, a method at a base station is provided. The method includes receiving a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The method also includes sending a second message as a response to the first message.

[0031] In a third aspect of the present disclosure, a method at a base station is provided. The method includes receiving a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The method also includes sending a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. The base station determines the beam used for the second message as one of the following: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0032] In a fourth aspect of the present disclosure, a method at a base station is provided. The method includes receiving a first message from a UE, the first message including a RACH preamble on a random access channel (RACH) timing and data on an uplink shared channel (USCH). The method also includes sending a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. The base station determines a radio network temporary identifier (RNTI) for the second message as one of the following: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE with a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0033] In a fifth aspect of the present disclosure, a method at a base station is provided. The method includes receiving a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) timing and data on an uplink shared channel (USCH). The method also includes sending a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. The base station determines a modulation and coding scheme (MCS) for the second message as one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0034] In one embodiment, the data includes information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard.

[0035] In a sixth aspect of the present disclosure, a method at a user equipment (UE) is provided. The method includes selecting a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard. The method also includes sending a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The method also includes receiving a second message from the base station as a response to the first message.

[0036] In one embodiment, the data includes an indication of at least one SSB having a signal measurement metric that meets a criterion.

[0037] In one embodiment, the at least one SSB indicated by the first message includes one or more SSBs associated with a RACH opportunity.

[0038] In one embodiment, the at least one SSB indicated by the first message includes an SSB in a set of SSBs having a signal measurement metric that satisfies a criterion except for an SSB indicated by a RACH preamble and a RACH opportunity.

[0039] In one embodiment, at least one SSB is indicated by a list ordered by a signal measurement metric or by a bitmap.

[0040] In one embodiment, the RACH is a physical random access channel (PRACH), the USCH is a physical uplink shared channel (PUSCH), and the signal measurement metric is a reference signal received power (RSRP), or a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) based on downlink signal measurements.

[0041] In one embodiment, the criterion is that the signal measurement metric is greater than or not less than a threshold value.

[0042] In one embodiment, the second message can multiplex respective responses to respective first messages of the UE and at least one other UE.

[0043] In one embodiment, a UE and at least one other UE having the same determined MCS are multiplexed in the second message; a UE and at least one other UE having a specific common SSB that satisfies a standard signal measurement metric are multiplexed in the second message; a UE and at least one other UE sending a RACH preamble mapped to the same SSB are multiplexed in the second message; and / or a UE and at least one other UE having the same downlink preferred beam are multiplexed in the second message.

[0044] In one embodiment, the beam used for the second message is one of: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0045] In one embodiment, the radio network temporary identifier (RNTI) used for the second message is one of: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0046] In one embodiment, when the at least one other UE and the UE send the first message on the same RACH opportunity, the common RNTI is calculated based on the same RACH opportunity, or the common RNTI is a group RNTI defined for the UE and at least one other UE; or the common RNTI is indicated in the corresponding first messages from the UE and at least one other UE.

[0047] In a seventh aspect of the present disclosure, a method at a base station is provided. The method includes receiving a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). The RACH preamble or RACH opportunity indicates an SSB selected by the UE based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The selected SSB has a signal measurement metric that meets a standard. The method also includes sending a second message to the UE as a response to the first message.

[0048] In one embodiment, the data includes information indicating at least one SSB having a signal measurement metric that meets the criteria, and the method further includes: selecting a downlink beam for sending a second message to the UE based on the indication in the data.

[0049] In an eighth aspect of the present disclosure, an apparatus at a user equipment (UE) is provided. The apparatus includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to select a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that satisfies a standard. The apparatus further operates to send a first message to a base station, the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). The RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The apparatus further operates to receive a second message from the base station as a response to the first message.

[0050] In a ninth aspect of the present disclosure, a device at a base station is provided. The device includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the device is operable to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the RACH preamble or the RACH opportunity indicates an SSB selected by the UE based on a mapping of the SSB to the RACH preamble and the RACH opportunity; wherein the selected SSB has a signal measurement metric that meets a standard. The device further operates to send a second message to the UE as a response to the first message.

[0051] In another aspect of the present disclosure, an apparatus at a user equipment (UE) is provided. The apparatus includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to send a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The apparatus further operates to receive a second message as a response to the first message.

[0052] In another aspect of the present disclosure, an apparatus at a base station is provided. The base station includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The apparatus further operates to send a second message as a response to the first message.

[0053] In another aspect of the present disclosure, an apparatus at a base station is provided. The base station includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The apparatus further operates to send a second message as a corresponding response to the corresponding first messages of the UE and at least one other UE. The base station determines the beam used for the second message to be one of the following: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0054] In another aspect of the present disclosure, an apparatus at a base station is provided. The base station includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The apparatus further operates to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. The base station determines a radio network temporary identifier (RNTI) for the second message as one of the following: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE with a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0055] In another aspect of the present disclosure, an apparatus at a base station is provided. The base station includes a processor; and a memory coupled to the processor, the memory storing instructions executable by the processor, whereby the apparatus is operable to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The apparatus further operates to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. The base station determines a modulation coding scheme (MCS) of the second message as one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0056] In another aspect of the present disclosure, a UE is provided. The UE includes a sending module and a receiving module. The sending module is configured to send a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The receiving module is configured to receive a second message as a response to the first message.

[0057] In another aspect of the present disclosure, a base station is provided. The base station includes a receiving module and a sending module. The receiving module is configured to receive a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). The sending module is configured to send a second message as a response to the first message.

[0058] In another aspect of the present disclosure, a base station is provided. The base station includes a receiving module and a sending module. The receiving module is configured to receive a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH). The sending module is configured to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In one embodiment, the base station may determine the beam used for the second message as one of the following: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0059] In another aspect of the present disclosure, a base station according to an embodiment of the present disclosure is provided. The base station includes a receiving module and a sending module. The receiving module is configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The sending module is configured to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In one embodiment, the base station may determine a radio network temporary identifier (RNTI) for the second message as one of the following: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE with a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0060] In another aspect of the present disclosure, a base station according to an embodiment of the present disclosure is provided. The base station includes a receiving module and a sending module. The receiving module is configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The sending module is configured to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In one embodiment, the base station may determine a modulation coding scheme (MCS) for the second message as one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0061] In another aspect of the present disclosure, a user equipment (UE) is provided. The UE includes a selection module, a sending module, and a receiving module. The selection module is configured to select a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard. The sending module is configured to send a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The receiving module is configured to receive a second message from the base station as a response to the first message.

[0062] In another aspect of the present disclosure, a base station is provided. The base station includes a receiving module and a sending module. The receiving module is configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The RACH preamble or RACH opportunity indicates an SSB selected by the UE based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The selected SSB has a signal measurement metric that meets a standard. The sending module is configured to send a second message to the UE as a response to the first message.

[0063] In another aspect of the present disclosure, a computer program product is provided, which includes instructions. When the instructions are executed on at least one processor, the instructions cause the at least one processor to perform the method according to any one of the first to seventh aspects above.

[0064] In another aspect of the present disclosure, a computer-readable storage medium storing instructions is provided. When the instructions are executed by at least one processor, the instructions cause the at least one processor to perform a method according to any one of the first to seventh aspects above.

[0065] According to another aspect of the present disclosure, a method implemented in a communication system including a host computer, a base station and a terminal device is provided. The method includes providing user data at the host computer. The method also includes initiating a transmission carrying user data to the terminal device via a cellular network including the base station at the host computer. The base station is used to perform the method described in any one of the second to fifth and seventh aspects above.

[0066] According to another aspect of the present disclosure, a communication system is provided, the communication system comprising a host computer, the host computer comprising a processing circuit configured to provide user data and a communication interface configured to forward the user data to a cellular network for transmission to a terminal device. The cellular network comprises a base station having a radio interface and a processing circuit. The processing circuit of the base station is configured to perform the method according to any one of the second to fifth and seventh aspects above.

[0067] According to the twentieth aspect of the present disclosure, a method implemented in a communication system including a host computer, a base station and a terminal device is provided. The method includes providing user data at the host computer. The method also includes initiating a transmission carrying user data to the terminal device via a cellular network including the base station at the host computer. The terminal device is configured to perform the method described in any one of the first and sixth aspects above.

[0068] According to another aspect of the present disclosure, a communication system is provided, the communication system comprising a host computer, the host computer comprising a processing circuit configured to provide user data and a communication interface configured to forward the user data to a cellular network for transmission to a terminal device. The terminal device comprises a radio interface and a processing circuit. The processing circuit of the terminal device is configured to perform the method according to any one of the first and sixth aspects above.

[0069] According to another aspect of the present disclosure, a method implemented in a communication system including a host computer, a base station and a terminal device is provided. The method includes receiving user data transmitted from the terminal device to the base station at the host computer. The terminal device is configured to execute the method described in any one of the first and sixth aspects above.

[0070] According to another aspect of the present disclosure, a communication system is provided, the communication system comprising a host computer, the host computer comprising a communication interface, the communication interface being configured to receive user data originating from a transmission from a terminal device to a base station. The terminal device comprises a radio interface and a processing circuit. The processing circuit of the terminal device is configured to perform the method according to any one of the first and sixth aspects above.

[0071] According to another aspect of the present disclosure, a method implemented in a communication system including a host computer, a base station and a terminal device is provided. The method includes receiving, at the host computer, from the base station user data originating from a transmission that the base station has received from the terminal device. The base station is configured to perform the method described in any one of the second to fifth and seventh aspects above.

[0072] According to another aspect of the present disclosure, a communication system is provided, the communication system comprising a host computer, the host computer comprising a communication interface, the communication interface being configured to receive user data originating from a transmission from a terminal device to a base station. The base station comprises a radio interface and a processing circuit. The processing circuit of the base station is configured to perform the method according to any one of the second to fifth and seventh aspects above. BRIEF DESCRIPTION OF THE DRAWINGS

[0073] The above and other aspects, features and benefits of various embodiments of the present disclosure will become more fully apparent from the following detailed description with reference to the accompanying drawings, by way of example, in which like reference numerals or letters are used to refer to similar or equivalent elements. The accompanying drawings are shown to facilitate a better understanding of the embodiments of the present disclosure and are not necessarily drawn to scale, wherein:

[0074] Figure 1 A flow chart showing a 4-step random access process;

[0075] Figure 2 A flow chart showing a 2-step random access process;

[0076] Figure 3a A flowchart of a method according to an embodiment of the present disclosure is shown;

[0077] Figure 3b A flowchart of a method according to an embodiment of the present disclosure is shown;

[0078] Figure 4 A flowchart of a method according to another embodiment of the present disclosure is shown;

[0079] Figure 5 A flowchart of a method according to another embodiment of the present disclosure is shown;

[0080] Figure 6 A flowchart of a method according to another embodiment of the present disclosure is shown;

[0081] Figure 7a A flowchart of a method according to another embodiment of the present disclosure is shown;

[0082] Figure 7b A flowchart of a method according to another embodiment of the present disclosure is shown;

[0083] Figure 8 is a block diagram illustrating an apparatus suitable for practicing some embodiments of the present disclosure;

[0084] Fig. 9 A simplified block diagram of an apparatus according to an embodiment of the present disclosure is shown;

[0085] Fig.10 A simplified block diagram of an apparatus according to an embodiment of the present disclosure is shown;

[0086] Fig.11 A simplified block diagram of an apparatus according to another embodiment of the present disclosure is shown;

[0087] Fig.12 A simplified block diagram of an apparatus according to another embodiment of the present disclosure is shown;

[0088] Fig.13a shows a simplified block diagram of an apparatus according to another embodiment of the present disclosure;

[0089] Fig.13b is a block diagram showing a user equipment (UE) according to another embodiment of the present disclosure;

[0090] Fig.13c is a block diagram showing a base station according to another embodiment of the present disclosure;

[0091] Fig.14 is a diagram illustrating a telecommunications network connected to a host computer via an intermediate network according to some embodiments;

[0092] Fig.15 is a diagram illustrating a host computer communicating with a user device via a base station according to some embodiments;

[0093] Fig.16 is a flow chart illustrating a method implemented in a communication system according to some embodiments;

[0094] Fig.17 is a flow chart illustrating a method implemented in a communication system according to some embodiments;

[0095] Fig.18 is a flow chart illustrating a method implemented in a communication system according to some embodiments; and

[0096] Fig.19is a flow chart illustrating a method implemented in a communication system according to some embodiments. DETAILED DESCRIPTION

[0097] Embodiments of the present disclosure are described in detail with reference to the accompanying drawings. It should be understood that these embodiments are discussed only for the purpose of enabling those skilled in the art to better understand and thus realize the present disclosure, rather than suggesting any limitation on the scope of the present disclosure. References to features, advantages or similar language throughout the specification do not mean that all features and advantages that can be implemented with the present disclosure should be in or in any single embodiment of the present disclosure. On the contrary, the language referring to features and advantages should be understood to mean that specific features, advantages or characteristics described in conjunction with the embodiments are included in at least one embodiment of the present disclosure. In addition, in one or more embodiments, the features, advantages and characteristics described in the present disclosure may be combined in any suitable manner. Those skilled in the relevant art will recognize that the present disclosure may be practiced without one or more of the specific features or advantages of a particular embodiment. In other cases, additional features and advantages may be recognized in certain embodiments, and the additional features and advantages may not exist in all embodiments of the present disclosure.

[0098] As used herein, the term "network" refers to a network that complies with any suitable communication standard, such as first generation (1G), 2G, 2.5G, 2.75G, 3G, 4G, 4.5G, 5G communication protocols, and / or any other currently known or future developed communication standards. In the following description, the terms "network" and "system" can be used interchangeably. In addition, the communication between the terminal equipment and the network node in the communication system can be performed according to any suitable communication protocol of each generation, including but not limited to 1G, 2G, 2.5G, 2.75G, 3G, 4G, 4.5G, 5G communication protocols and / or any other currently known or future developed protocols. In addition, the specific terms used herein do not limit the present disclosure to the communication system associated with the specific terms, but the present disclosure can be more generally applied to other communication systems.

[0099] The term "base station" refers to an access network device in a communication network, through which a terminal device accesses the network and receives services therefrom. For example, a base station (BS) may include, but is not limited to, an integrated access backhaul (IAB) node, an access point (AP), a multi-cell / multicast coordination entity (MCE), etc. A BS may be, for example, a Node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), a next generation NodeB (gNodeB or gNB), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), a repeater, a low power node (such as a femto, a pico), etc.

[0100] The term "terminal device" refers to any terminal device that can access a communication network and receive services therefrom. As an example and not a limitation, in a wireless communication network, a terminal device may refer to a mobile terminal, a user equipment (UE), a terminal device, or other suitable device. The terminal device may be, for example, a subscriber station (SS), a portable subscriber station, a mobile station (MS), or an access terminal (AT). The terminal device may include, but is not limited to, a portable computer, an image capture device such as a digital camera, a game terminal device, a music storage and playback device, a mobile phone, a cellular phone, a smart phone, a voice over IP (VoIP) phone, a wireless local loop phone, a tablet computer, a wearable device, a personal digital assistant (PDA), a portable computer, a desktop computer, a wearable device, a vehicle-mounted wireless device, a wireless endpoint, a mobile station, a laptop embedded device (LEE), a laptop mounted device (LME), a USB dongle, a smart device, a wireless customer premises equipment (CPE), etc. In the following description, the terms "terminal device", "terminal", "user equipment" and "UE" may be used interchangeably. As an example, a UE may represent a terminal device configured to communicate in accordance with one or more communication standards published by 3GPP (e.g., 3GPP's LTE standard or NR standard). As used herein, a "user equipment" or "UE" may not necessarily have a "user" in terms of a human user who owns and / or operates the associated device. In some embodiments, a terminal device may be configured to send and / or receive information without direct human interaction. For example, when triggered by an internal or external event, or in response to a request from a wireless communication network, a UE may be designed to send information to the network according to a predetermined schedule. Alternatively, a UE may represent a device that is intended to be sold to a human user or operated by a human user but may not initially be associated with a specific human user.

[0101] As another example, in an Internet of Things (IoT) scenario, a terminal device may represent a machine or other device that performs monitoring and / or measurement, and sends the results of such monitoring and / or measurement to another terminal device and / or network device. In this case, the UE may be a machine-to-machine (M2M) device, which may be referred to as a machine type communication (MTC) device in the 3GPP context. As a specific example, the terminal device may be a UE that implements the 3GPP Narrowband Internet of Things (NB-IoT) standard. Specific examples of such machines or devices are sensors, metering devices (e.g., electricity meters, industrial machinery) or household or personal appliances (e.g., refrigerators, televisions), personal wearable devices (e.g., watches), etc. In other scenarios, the UE may represent a vehicle or other device that is capable of monitoring and / or reporting its operating status or other functions related to its operation.

[0102] References in the specification to "one embodiment," "an embodiment," "an exemplary embodiment," etc. indicate that the described embodiment may include a particular feature, structure, or characteristic, but not necessarily every embodiment includes the particular feature, structure, or characteristic. Furthermore, these phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described in conjunction with an embodiment, whether or not explicitly described, it is considered to be within the knowledge of those skilled in the art to affect such feature, structure, or characteristic in relation to other embodiments.

[0103] It should be understood that although the terms "first" and "second" etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the exemplary embodiments, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed terms.

[0104] The terms used herein are for the purpose of describing specific embodiments only and are not intended to limit the example embodiments. Unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" as used herein are also intended to include the plural forms. It will be further understood that when used herein, the terms "include", "comprise", "have", "have", "contain" and / or "cover" specify the presence of the features, elements and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0105] As used herein, downlink DL transmission refers to transmission from a network device to a terminal device, and uplink UL transmission refers to transmission in the opposite direction.

[0106] Note that these terms used in this article are only used to facilitate description and to distinguish between nodes, devices or networks, etc. As technology develops, other terms with similar / same meanings may also be used.

[0107] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0108] Note that although the embodiments are primarily described in the context of a 2-step random access procedure and NR, they are not limited thereto and may be applied to any suitable random access procedure and network.

[0109] Figure 3aA flow chart of a method 300 according to an embodiment of the present disclosure is shown, which can be performed by a device in or at a UE or any other entity with similar functions or a device communicatively coupled to the UE or any other entity with similar functions. Therefore, the UE can provide components for completing various parts of the method 300 and components for completing other processes in combination with other components.

[0110] In block 302, the UE sends a first message to the base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). As described above, before initiating a random access procedure, the UE may need to go through an initial synchronization procedure. For example, the UE detects a synchronization signal (SS), such as a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The UE then decodes the broadcasted system information (e.g., PBCH, RMSI (remaining minimum system information), OSI (other system information), etc.).

[0111] The first message may be referred to herein as msgA. In one embodiment, the first message may be a layer 1 message. The data on the USCH may include any suitable information. For example, the data on the USCH may include higher layer data on the PUSCH, which may carry some small payload, such as an RRC connection request. In one embodiment, the channel structure of msgA may be a PRACH preamble and a PUSCH carrying a payload. In one embodiment, the SSB may correspond to an SS / PBCH block in NR. In one embodiment, the first message may also include the equivalent content of msg3 for a 4-step random access procedure. In one embodiment, the first message may reuse the 3GPP Release 15 NR PUSCH for transmission of the payload of msgA, which includes the Rel-15 DMRS (demodulation reference signal).

[0112] The RACH preamble may be any suitable preamble for the random access procedure. For example, the RACH preamble may reuse the 3GPP Release 15NR PRACH preamble design. In one embodiment, there may be a mapping between the PRACH preamble and the time-frequency resources of the PUSCH in msgA+DMRS. In one embodiment, there may be any suitable supported modulation and coding scheme (MCS) and time-frequency resource size of the PUSCH in msgA. In one embodiment, there may be any suitable power control of the PUSCH of msgA. In one embodiment, UCI (uplink control information) may be included in msgA.

[0113] Since the reporting of SSBs in the 4-step random access procedure is done explicitly only by the SSB to RO and preamble mapping, it is only possible to indicate a single SSB by the preamble transmission. This makes it difficult for a base station such as a gNB to know whether a UE indicating a beam corresponding to, for example, SSB1 will be able to receive msgB transmitted on a beam corresponding to, for example, SSB2. Improved SSB reporting by the UE may be performed by reporting more than one beam or SSB in a msgA transmission. There may be multiple ways to report more than one SSB in the 2-step random access procedure.

[0114] In one embodiment, the data may include information of at least one synchronization signal and physical broadcast channel block (SSB) having a signal measurement metric that meets the standard. The signal measurement metric may be any suitable signal measurement metric based on downlink signal measurement. In one embodiment, the signal measurement metric may be a reference signal received power (RSRP), or a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) based on downlink signal measurement. The reference signal may be any suitable reference signal, such as a synchronization signal reference signal, etc. In one embodiment, the signal may be a layer 1 signal. For example, the data may include information of at least one SSB having a synchronization signal RSRP (SS-RSRP) higher than rsrp-ThresholdSSB. rsrp-ThresholdSSB is described in 3GPP TS 38.321V15.5.0, the disclosure of which is incorporated herein by reference in its entirety.

[0115] In one embodiment, the criterion may be a threshold value, and the signal measurement metric satisfying the criterion may include a signal measurement metric that is greater than or not less than the threshold value.

[0116] In one embodiment, at least one SSB having a signal measurement metric that meets the standard may include a subset or set of all SSBs having a signal measurement metric that meets the standard. The set of all SSBs having a signal measurement metric that meets the standard may be determined by measuring the signal measurement metric of the SSB candidate set and comparing the signal measurement metric with the corresponding standard. The standard may be predefined or indicated in at least one of the system information and the dedicated higher layer control signaling. For example, the selected preamble and / or RO may indicate the best beam. The data on the USCH may indicate a subset of all SSBs having an SS-RSRP higher than rsrp-ThresholdSSB. The set of all SSBs having an SS-RSRP higher than rsrp-ThresholdSSB may be determined by measuring the power of the candidate set of SSBs and comparing the measured power with rsrp-ThresholdSSB. In another example, a threshold different from rsrp-ThresholdSSB may be used, and the threshold may be predefined or indicated in at least one of the system information and the dedicated higher layer control signaling.

[0117] In one embodiment, at least one SSB having a signal measurement metric that meets the criteria includes an SSB associated with a RACH opportunity. For example, at least one SSB corresponds to an SSB associated with a RACH opportunity. One advantage of this embodiment is that a fixed set of SSBs is associated with each RACH opportunity, and since the RNTI can be used to identify at least the RACH opportunity, signaling only needs to identify a fixed set of SSBs associated with the RO, which can reduce signaling overhead compared to at least one SSB from multiple ROs. For example, each SSB can be identified by a bit in the signaling, and if the signal measurement metric of the SSB meets the criteria, the corresponding bit can be set to 1, otherwise the corresponding bit can be set to 0. In some embodiments, the association between the RO and the preamble in the RO can be performed according to subclause 8.1 of 3GPP TS 38.213 V15.6.0, the disclosure of which is incorporated herein by reference in its entirety.

[0118] In one embodiment, the at least one SSB having a signal measurement metric that satisfies the criterion includes an SSB in a set of SSBs having a signal measurement metric that satisfies the criterion other than an SSB indicated by a RACH preamble and a RACH opportunity. For example, the at least one SSB may be an SSB in a set of SSBs having an SS-RSRP higher than rsrp-ThresholdSSB other than an SSB indicated by a preamble and an RO.

[0119] In one embodiment, at least one SSB having a signal measurement metric that satisfies the criterion includes all SSBs in a set of SSBs having a signal measurement metric that satisfies the criterion. For example, all SSBs in a set of SSBs having an SS-RSRP higher than rsrp-ThresholdSSB are indicated in the PUSCH of msgA. The set of SSBs having an SS-RSRP higher than rsrp-ThresholdSSB may be determined by measuring the power of a candidate set of SSBs and comparing the measured power to rsrp-ThresholdSSB.

[0120] In various embodiments, the criterion may be predefined (eg, rsrp-ThresholdSSB) or indicated in system information and / or non-access stratum layer control signaling. When the criterion is indicated in system information and / or non-access stratum layer control signaling, the criterion may be updated.

[0121] In one embodiment, at least one SSB is indicated by using a list sorted by a signal measurement metric. For example, a sorted list sorted, for example by SS-RSRP, is used in the PUSCH of msgA to indicate a set of SSBs having SS-RSRP above a received power threshold. The threshold may be rsrp-ThresholdSSB or a threshold different from rsrp-ThresholdSSB. The threshold may be indicated in at least one of system information and dedicated high-level control signaling. In one embodiment, each element of the sorted list includes a corresponding index of at least one SSB. For example, each element of the list may include an index of an SSB on which the SS-RSRP is measured. In one embodiment, each element of the sorted list includes an indication of a value of a signal measurement metric for at least one SSB. For example, an element of the list may include an indication of a value of the SS-RSRP measured on the SSB.

[0122] In one embodiment, at least one SSB is indicated by using a bitmap. For example, a set of SSBs with SS-RSRP above a received power threshold is indicated in the PUSCH of msgA using a bitmap. In one embodiment, each bit in the bitmap corresponds to only one SSB, and all bits in the bitmap correspond to one RO. In another embodiment, each bit in the bitmap corresponds to only one SSB, and all bits in the bitmap correspond to all SSBs used in the base station. In yet another embodiment, 1 bit in the bitmap may be mapped to a subset of the SSBs considered, and all bits in the bitmap are mapped to the complete set of SSBs considered.

[0123] In one embodiment, the RACH preamble and RACH opportunity are selected based on the mapping of SSB to RACH preamble and RACH opportunity. For example, Section 8.1 of 3GPP TS 38.213 V15.6.0 specifies detailed mapping rules. The UE will select an SSB with an SS-RSRP higher than the rsrp-ThresholdSSB (if such an SSB is available). The selected SSB will be indicated to the gNB via the selected preamble or via the PRACH opportunity (RO). This indication will enable the gNB to select a suitable DL beam for RAR transmission. SSB selection and preamble transmission (and mapping RO to SSB) can be similar to those specified in Section 5.1.2 of 3GPP TS 38.321 V15.5.0, the disclosure of which is incorporated herein by reference in its entirety.

[0124] In one embodiment, the RACH preamble and RACH timing are selected based on predefined rules. For example, when a set of SSBs with SS-RSRP above a received power threshold is indicated in the PUSCH of msgA, the mapping of SSBs to preambles and ROs can be removed. In this case, the RACH preamble and RACH timing can be selected based on predefined rules, which can provide more available ROs and preambles for random access indicating a specific SSB. The predefined rule can be a random selection rule or any other suitable selection rule.

[0125] In one embodiment, the RACH is a Physical Random Access Channel (PRACH). In one embodiment, the USCH is a Physical Uplink Shared Channel (PUSCH).

[0126] In block 304, the UE receives a second message as a response to the first message. The second message (e.g., msgB) may include any suitable information, such as the equivalent content of msg2 and msg4 of the 4-step random access procedure. The second message may be a layer 1 message. In one embodiment, for a response to a successfully decoded msgA, msgB should include a TA (timing advance) command, a contention resolution ID, etc. For a response to an undecoded msgA, msgB may be a fallback message, or even a normal RAR (msg2).

[0127] In one embodiment, the second message may include one or more of an assigned identifier of the UE, timing advance information, and a contention resolution message.

[0128] In one embodiment, the second message may multiplex the corresponding responses to the corresponding first messages of the UE and at least one other UE. In this case, the second message also includes the corresponding response to the corresponding first message of the at least one other UE. For example, for CCCH, for a successful or fallback RAR, MsgB may multiplex messages for multiple UEs, and MsgB is transmitted in one PDSCH. In another embodiment, MsgB containing a successful RAR should not be multiplexed in the same MAC PDU with a conventional 4-step RACH RAR.

[0129] Which UEs may be multiplexed in the second message may be determined in various ways. In one embodiment, UEs having the same determined MCS may be multiplexed in the second message. In one embodiment, UEs having a specific common SSB that satisfies a standard signal measurement metric may be multiplexed in the second message. In one embodiment, UEs that send RACH preambles mapped to the same SSB may be multiplexed in the second message. In one embodiment, UEs having the same downlink preferred beam may be multiplexed in the second message. The preferred beam of the UE may be indicated to the base station in a variety of ways. For example, when the UE detects the best SSB beam (i.e., the preferred beam), a PRACH preamble from a set of one or more PRACH preambles mapped to the SSB is selected for random access, and then when the base station (such as a gNB) detects the PRACH preamble, the best SSB beam for the UE is indirectly known so that the best beam can be used to send signals to or receive signals from the UE. In this case, the preferred beam of the UE may correspond to the best SSB beam. In other embodiments, the UE's preferred beam may correspond to the SSB beam having the best signal measurement metric that meets the criteria (eg, highest RSRP, or best RSRQ, or maximum SINR).

[0130] The beam used for the second message may be determined in various ways, for example, by the base station. In one embodiment, the beam used for the second message may be a common downlink beam of the UE and at least one other UE. For example, the beam used for the combined msgB transmission may be a common downlink beam preferred by the UE, which requires that the combination is only used in a group of UEs having at least one identical downlink preferred beam. For example, when 64 preambles are allocated, and each RO is mapped by 4 SSBs and 16 preambles are mapped to each SSB, then only UEs that send some of the 16 preambles mapped to one SSB may be combined in msgB.

[0131] In one embodiment, the beam used for the second message may be a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE. For example, the beam used for the combined msgB transmission may be a wide beam that covers at least one of the preferred beam of the UE and the preferred beam of at least one other UE.

[0132] In one embodiment, the beam used for the second message may be a preferred beam for a UE with a higher priority between the UE and at least one other UE. For example, the beam used for combined msgB transmission may be determined based on the priority of the UE's data. For example, a preferred beam for data transmission of a UE with a higher priority may be used. Priority may be based on random access type, such as 2-step RA priority. Priority may be based on service type, such as uRLLC (ultra-reliable low latency communication) UE priority.

[0133] In one embodiment, the beam used for the second message may be a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE. For example, the beam used for the second message is randomly selected from a set of beams preferred by a group of UEs having data combined in one msgBPDSCH.

[0134] In one embodiment, the beam used for the second message may be determined based on a common SSB from a plurality of SSBs reported by the UE. For example, a UE that has reported a common SSB in a set of SSBs (one from each UE) with SS-RSRP above rsrp-ThresholdSSB is selected to be combined in the PDSCH of one msgB.

[0135] The radio network temporary identifier (RNTI) for the second message may be determined in various ways, for example, by the base station. In one embodiment, the RNTI for the second message may be a common RNTI for the UE and at least one other UE. The common RNTI may be determined in various ways. In one embodiment, when at least one other UE and the UE send the first message on the same RACH opportunity, the common RNTI is calculated based on the same RACH opportunity. In one embodiment, the common RNTI is a group RNTI defined for the UE and at least one other UE. In one embodiment, the common RNTI is indicated in the corresponding first message from the UE and at least one other UE. For example, the RNTI for the combined msgB transmission is a common RNTI for the UE group combined in the msgB transmission. The common RNTI may be obtained by one or more of the following methods: the UE group is those UEs that have a preamble sent on the same RACH opportunity so that a common random access RNTI (RA-RNTI) or a common RNTI related to the RA-RNTI can be obtained; a separately defined group RNTI is used for the UE group combined in one msgB transmission; the common RNTI to be used is indicated in the msgA PUSCH from the UE.

[0136] In one embodiment, the RNTI used for the second message may be a UE-specific RNTI of a UE having a higher priority between the UE and at least one other UE. In one embodiment, the RNTI used for the second message may be a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE. In one embodiment, the RNTI used for the second message may be a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE. In one embodiment, when the RNTI used for the second message is a UE-specific RNTI, the downlink control information includes a system frame number to indicate whether the corresponding second message is for the UE. For example, the RNTI used for msgB transmission is still a UE-specific msgB RNTI, and multiple PDCCHs (physical downlink control channels) may be transmitted to schedule multiple UEs on the same PDSCH. Which RNTI is used for PDSCH data scrambling can be indicated in the corresponding L1 signaling, which can be determined by one or more of the following methods: random selection; RA type, for example, 2-step RA UE can be prioritized; service type, for example, uRLLCUE can be prioritized; measurement of the received signal from the UE or the UE's measurement of the downlink signal, such as signal strength, signal quality.

[0137] In one embodiment, the UE-specific RNTI is a random access RNTI (RA-RNTI). The RA-RNTI may be similar to the RA-RNTI described in 3GPP TS 38.321 V15.5.0. For example, the RNTI used for msgB transmission is still the UE-specific msgBRNTI, and multiple PDCCHs may be sent to schedule multiple UEs on the same PDSCH. SFN (system frame number) information may be included in the DCI (downlink control information) to indicate whether the corresponding PDSCH is for the UE. In this way, the RA-RNTI may be used by multiple UEs that transmit preambles on different system frames.

[0138] In one embodiment, the modulation and coding scheme (MCS) for the second message may be determined, for example, by the base station as an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE. For example, the MCS is typically determined by the network based on the quality of the UE, and there may be a variety of methods to determine a common MCS for a combined msgB transmission involving a group of UEs. For example, the UEs combined in the same msgB transmission require the same MCS, and the same MCS (and also the MCS table) may be determined based on UEs having one or more of the following characteristics: lowest signal / link quality; 2-step RA or 4-step RA; uRLLC service or eMBB service. In one embodiment, the lowest MCS is selected from the group of MCS values ​​determined for the UE group. In some embodiments, only a group of UEs with the same determined MCS are combined in one msgB transmission, and then the same determined MCS is selected.

[0139] Figure 3b A flow chart of a method 320 according to another embodiment of the present disclosure is shown, which can be performed by a device in or at a UE or any other entity having similar functions or a device communicatively coupled to the UE or any other entity having similar functions. Therefore, the UE can provide components for completing various parts of the method 320 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0140] At block 322, the UE selects a synchronization signal and physical broadcast channel block (SSB) having a signal measurement metric that meets the criteria.

[0141] At block 324, the UE sends a first message to the base station, the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). The RACH preamble and RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and RACH opportunity; and

[0142] At block 326, the UE receives a second message from the base station in response to the first message.

[0143] In one embodiment, the data includes information indicating at least one SSB having a signal measurement metric that meets a criterion.

[0144] In one embodiment, the at least one SSB indicated by the first message includes one or more SSBs associated with a RACH opportunity.

[0145] In one embodiment, the at least one SSB indicated by the first message includes an SSB in a set of SSBs having a signal measurement metric that satisfies a criterion except for an SSB indicated by a RACH preamble and a RACH opportunity.

[0146] In one embodiment, at least one SSB is indicated by a list ordered by a signal measurement metric or by a bitmap.

[0147] In one embodiment, the RACH is a physical random access channel (PRACH), the USCH is a physical uplink shared channel (PUSCH), and the signal measurement metric is a reference signal received power (RSRP), or a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) based on downlink signal measurements.

[0148] In one embodiment, the criterion is that the signal measurement metric is greater than or not less than a threshold value.

[0149] In one embodiment, the second message may multiplex respective responses to respective first messages of the UE and at least one other UE.

[0150] In one embodiment, a UE and at least one other UE having the same determined MCS are multiplexed in the second message; a UE and at least one other UE having a specific common SSB that satisfies a standard signal measurement metric are multiplexed in the second message; a UE and at least one other UE sending a RACH preamble mapped to the same SSB are multiplexed in the second message; and / or a UE and at least one other UE having the same downlink preferred beam are multiplexed in the second message.

[0151] In one embodiment, the beam used for the second message is one of: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0152] In one embodiment, the radio network temporary identifier (RNTI) used for the second message is one of: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0153] In one embodiment, when the at least one other UE and the UE send the first message on the same RACH opportunity, the common RNTI is calculated based on the same RACH opportunity, or the common RNTI is a group RNTI defined for the UE and at least one other UE; or the common RNTI is indicated in the corresponding first messages from the UE and at least one other UE.

[0154] Figure 4 A flow chart of a method 400 according to an embodiment of the present disclosure is shown, and the method can be performed by a device in or at a base station or any other entity having similar functions or a device communicatively coupled to a base station or any other entity having similar functions. Therefore, the base station can provide components for completing various parts of the method 400 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0155] At block 402, a base station receives a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH), wherein the data includes information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard. For example, the UE may receive a first message on a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). Figure 3a Block 302 of the embodiment sends a first message, and then the base station may receive the first message.

[0156] In block 404, the base station sends a second message as a response to the first message. For example, the second message may include only a response to the first message of the UE. In another example, when the second message is used to multiplex respective responses to the first messages corresponding to multiple UEs, the second message may also include respective responses to the first message of at least one other UE.

[0157] In one embodiment, the base station may multiplex the corresponding responses of the UE and the at least one other UE to the corresponding first messages in the second message.

[0158] In one embodiment, the base station may determine a beam for the second message, as described above. In one embodiment, the base station may determine a radio network temporary identifier (RNTI) for the second message, as described above. In one embodiment, the base station may determine a modulation and coding scheme (MCS) for the second message, as described above.

[0159] Figure 5 A flow chart of a method 500 according to an embodiment of the present disclosure is shown, and the method 500 can be performed by a device in or at a base station or any other entity with similar functions or communicatively coupled to a base station or any other entity with similar functions. Therefore, the base station can provide components for completing various parts of the method 500 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0160] In block 502, a base station receives a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). For example, when the data includes information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard, the UE may receive a first message on the RACH preamble. Figure 3a The first message is sent in block 302 of the present invention, and the base station may receive the first message. In another example, the data may not include information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets the standard.

[0161] At block 504, the base station sends a second message as a respective response to the respective first messages of the UE and at least one other UE. In this embodiment, the second message may multiplex the responses to the respective first messages of the UE and at least one other UE. The base station may determine the beam used for the second message to be one of the following: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0162] In one embodiment, the base station may determine a Radio Network Temporary Identifier (RNTI) for the second message as described above. In one embodiment, the base station may determine a Modulation Coding Scheme (MCS) for the second message as described above.

[0163] Figure 6 A flow chart of a method 600 according to an embodiment of the present disclosure is shown, and the method can be performed by a device in or at a base station or any other entity with similar functions or communicatively coupled to a base station or any other entity with similar functions. Therefore, the base station can provide components for completing various parts of the method 600 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0164] At block 602, a base station receives a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). For example, when the data includes information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard, the UE may receive a first message on the RACH preamble. Figure 3a The first message is sent in block 302 of the present invention, and the base station may receive the first message. In another example, the data may not include information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets the standard.

[0165] In block 604, the base station sends a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In this embodiment, the second message may multiplex the responses to the respective first messages of the UE and at least one other UE. The base station may determine a radio network temporary identifier (RNTI) for the second message as one of the following: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE with a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0166] In one embodiment, the base station may determine the beam for the second message as described above. In one embodiment, the base station may determine the modulation and coding scheme (MCS) for the second message as described above.

[0167] Figure 7a A flow chart of a method 700 according to an embodiment of the present disclosure is shown, and the method can be performed by a device in or at a base station or any other entity with similar functions or communicatively coupled to a base station or any other entity with similar functions. Therefore, the base station can provide components for completing various parts of the method 700 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0168] In block 702, a base station receives a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH). For example, when the data includes information of at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that satisfies a standard, the UE may Figure 3a In another example, the data may not include information including at least one synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets the standard.

[0169] In block 704, the base station sends a second message as a respective response to the respective first messages of the UE and at least one other UE. In this embodiment, the second message may multiplex the responses to the respective first messages of the UE and at least one other UE. The base station may determine a modulation and coding scheme (MCS) for the second message as one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0170] In one embodiment, the base station may determine the beam for the second message as described above.In one embodiment, the base station may determine the Radio Network Temporary Identifier (RNTI) for the second message as described above.

[0171] In a first embodiment, a method for an initial access procedure in a user equipment for indicating the quality of multiple reference signals is provided. The method comprises: a. Identify a candidate set of reference signals, wherein each element of the candidate set includes at least one of a primary synchronization signal, a secondary synchronization signal, and a channel state information reference signal b. Measure the received power of each element in the candidate set, c. Select the first candidate from the candidate set of reference signals d. Select a random access preamble from the set of random access preambles associated with the first candidate e. Send the random access preamble f. Determining an indication of a second candidate selected from the set of candidates, wherein the second candidate has a received power greater than a predetermined threshold. g. Sending an indication of the second candidate in a physical channel.

[0172] The method of the first embodiment, wherein the candidates in the candidate set include synchronization signal blocks. a. The second candidate is selected from a subset of all SSBs, wherein the subset of SSBs satisfies one or more of the following requirements: Associated with RO · is the set of SSBs not indicated by the preamble and RO is the set of SSBs with a measurement metric above a threshold 1. The threshold may be predetermined or sent from the network via RRC signaling, such as system information messages and / or UE-specific signaling 2. The measurement metric can be L1-RSRP, L1-RSRQ, L1-SINR or any other metric based on downlink signal measurement b. All methods in a can be applied to the entire set of SSB c. The second candidate is sent in a physical channel. The physical channel is msgA PUSCH The transmission is as follows: 1. Bitmap a. Each bit can be mapped to one or more SSBs that meet the requirements 2. Sorted List Transmission of SSB indicated in the physical channel can remove the mapping of SSB to preamble / RO

[0173] Figure 7b A flow chart of a method 720 according to an embodiment of the present disclosure is shown, and the method 720 can be performed by a device in or at a base station or any other entity with similar functions or communicatively coupled to a base station or any other entity with similar functions. Therefore, the base station can provide components for completing various parts of the method 720 and components for completing other processes in combination with other components. For the parts that have been described in the above embodiments, for the sake of brevity, they are not repeated here.

[0174] At block 722, the base station receives a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH). The RACH preamble or RACH opportunity indicates an SSB selected by the UE based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The selected SSB has a signal measurement metric that meets a criterion.

[0175] At block 724, the base station sends a second message to the UE in response to the first message.

[0176] In one embodiment, the data includes information indicating at least one SSB having a signal measurement metric that satisfies the criterion, and the method further includes: selecting a downlink beam for sending a second message to the UE based on the indication in the data.

[0177] Figure 8 800 is a block diagram showing an apparatus suitable for practicing some embodiments of the present disclosure. For example, any one of the above-mentioned UE and base station can be implemented by the apparatus 800.

[0178] The device 800 includes at least one processor 821, such as DP, and at least one memory 822 coupled to the processor 821. The device 820 may also include a transmitter TX and a receiver RX 823 coupled to the processor 821. The memory 822 stores a program 824. The program 824 may include instructions that, when executed on the associated processor 821, enable the device 820 to operate according to the embodiments of the present disclosure. The combination of at least one processor 821 and at least one memory 822 may form a processing device 825 suitable for implementing various embodiments of the present disclosure.

[0179] Various embodiments of the present disclosure may be implemented by a computer program executable by the processor 821 , one or more of software, firmware, hardware, or a combination thereof.

[0180] The memory 822 may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology such as, by way of non-limiting example, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.

[0181] Processor 821 may be of any type suitable for the local technical environment, and may include, by way of non-limiting example, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor DSP, and a processor based on a multi-core processor architecture.

[0182] Fig. 9 900 is a block diagram of a UE according to an embodiment of the present disclosure. As shown in the figure, the UE 900 includes a sending module 902 and a receiving module 904. Figure 3a As described in block 302 of the present invention, the sending module 902 may be configured to send a first message to the base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets the standard and information of a physical broadcast channel block (SSB). As described above with respect to Figure 3a As described in block 304 of FIG. 1 , the receiving module 904 may be configured to receive a second message in response to the first message.

[0183] Fig.10 1 is a block diagram of a base station according to an embodiment of the present disclosure. As shown in the figure, the base station 1000 includes a receiving module 1002 and a sending module 1004. Figure 4As described in block 402 of , the receiving module 1002 may be configured to receive a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH), wherein the data includes at least one synchronization signal having a signal measurement metric that meets a standard and information of a physical broadcast channel block (SSB). As described above with respect to Figure 4 As described in block 404 of FIG. 1 , the sending module 1004 may be configured to send a second message in response to the first message.

[0184] Fig.11 1 is a block diagram of a base station according to an embodiment of the present disclosure. As shown in the figure, the base station 1100 includes a receiving module 1102 and a sending module 1104. Figure 5 As described in block 502 of , the receiving module 1102 may be configured to receive a first message from a user equipment (UE), the first message including a random access channel (RACH) preamble on the RACH and data on an uplink shared channel (USCH). Figure 5 As described in block 504 of , the sending module 1104 may be configured to send the second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In one embodiment, the base station may determine the beam used for the second message as one of the following: a common downlink beam of the UE and at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of at least one other UE; a preferred beam of a UE having a higher priority between the UE and the at least one other UE; a beam randomly selected from the preferred beam of the UE and the preferred beam of at least one other UE.

[0185] Fig.12 1 is a block diagram of a base station according to an embodiment of the present disclosure. As shown in the figure, the base station 1200 includes a receiving module 1202 and a sending module 1204. Figure 6 As described in block 602 of , the receiving module 1202 may be configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). Figure 6As described in block 604 of , the sending module 1204 may be configured to send a second message as a corresponding response to the corresponding first message of the UE and at least one other UE. In one embodiment, the base station may determine a radio network temporary identifier (RNTI) for the second message as one of the following: a common RNTI of the UE and at least one other UE; a UE-specific RNTI of a UE with a higher priority between the UE and at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of at least one other UE; a UE-specific RNTI determined based on measurements of uplink signals from the UE and at least one other UE or measurements of downlink signals by the UE and at least one other UE.

[0186] Fig.13a 1 is a block diagram of a base station according to an embodiment of the present disclosure. As shown in the figure, the base station 1300 includes a receiving module 1302 and a sending module 1304. Figure 7a As described in block 702 of , the receiving module 1302 may be configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). Figure 7a As described in box 704, the sending module 1304 can be configured to send a second message as a corresponding response to the corresponding first messages of the UE and at least one other UE. In one embodiment, the base station may determine the modulation and coding scheme (MCS) for the second message as one of the following: an MCS corresponding to the lowest signal / link quality between the signal / link quality of the UE and the signal / link quality of at least one other UE; an MCS corresponding to the signal / link quality of a UE with a higher priority between the UE and the at least one other UE; an MCS with the lowest coding rate and / or the lowest modulation order selected from a set of MCSs determined for the UE and at least one other UE.

[0187] Fig.13b1320 is a block diagram illustrating a user equipment (UE) according to another embodiment of the present disclosure. UE 1320 includes a selection module 1321, a sending module 1322, and a receiving module 1323. The selection module 1321 is configured to select a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard. The sending module 1322 is configured to send a first message to a base station, the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The receiving module 1323 is configured to receive a second message from the base station as a response to the first message.

[0188] Fig.13c 13 is a block diagram showing a base station according to another embodiment of the present disclosure. The base station 1330 includes a receiving module 1331 and a sending module 1332. The receiving module 1331 is configured to receive a first message from a user equipment (UE), the first message including a RACH preamble on a random access channel (RACH) opportunity and data on an uplink shared channel (USCH). The RACH preamble or RACH opportunity indicates an SSB selected by the UE based on a mapping of the SSB to the RACH preamble and the RACH opportunity. The selected SSB has a signal measurement metric that meets a standard. The sending module 1332 is configured to send a second message to the UE as a response to the first message.

[0189] Reference Fig.14 According to an embodiment, a communication system includes a telecommunication network 3210, such as a 3GPP type cellular network, which includes an access network 3211, such as a radio access network, and a core network 3214. The access network 3211 includes a plurality of base stations 3212a, 3212b, 3212c, such as NBs, eNBs, gNBs or other types of wireless access points, each of which defines a corresponding coverage area 3213a, 3213b, 3213c. Each base station 3212a, 3212b, 3212c can be connected to the core network 3214 via a wired or wireless connection 3215. A first UE 3291 located in the coverage area 3213c is configured to be wirelessly connected to or paged by the corresponding base station 3212c. A second UE 3292 located in the coverage area 3213a can be wirelessly connected to the corresponding base station 3212a. Although multiple UEs 3291 , 3292 are shown in this example, the disclosed embodiments are equally applicable to situations where only a UE is in the coverage area or a only UE is connected to the corresponding base station 3212 .

[0190] The telecommunications network 3210 itself is connected to a host computer 3230, which may be embodied in the hardware and / or software of a standalone server, a cloud-implemented server, a distributed server, or as a processing resource in a server farm. The host computer 3230 may be under the ownership or control of a service provider, or may be operated by or on behalf of the service provider. Connections 3221 and 3222 between the telecommunications network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230, or may extend to the host computer 3230 through an optional intermediate network 3220. The intermediate network 3220 may be one of the following, or a combination of more than one of the following: a public network, a private network, or a hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may include two or more sub-networks (not shown).

[0191] Fig.14 The communication system as a whole enables connectivity between connected UEs 3291, 3292 and a host computer 3230. The connectivity may be described as an over-the-top (OTT) connection 3250. The host computer 3230 and the connected UEs 3291, 3292 are configured to transmit data and / or signaling via the OTT connection 3250 using the access network 3211, the core network 3214, any intermediate networks 3220, and possible further infrastructure (not shown) as intermediaries. The OTT connection 3250 may be transparent in the sense that the participating communication devices through which the OTT connection 3250 passes are unaware of the routing of uplink and downlink communications. For example, the base station 3212 may not or need to be informed of the past routing of incoming downlink communications having data originating from the host computer 3230 to be forwarded (e.g., handed over) to the connected UE 3291. Similarly, the base station 3212 does not need to know the future routing of outgoing uplink communications from the UE 3291 to the host computer 3230.

[0192] According to the embodiment, reference will now be made to Fig.15Describe the example implementations of the UE, base station, and host computer discussed in the previous paragraphs. In the communication system 3300, the host computer 3310 includes: hardware 3315, which includes a communication interface 3316, which is configured to establish and maintain a wired or wireless connection with the interface of different communication devices of the communication system 3300. The host computer 3310 also includes a processing circuit 3318, which may have storage and / or processing capabilities. In particular, the processing circuit 3318 may include: one or more programmable processors, application specific integrated circuits, field programmable gate arrays, or a combination of these (not shown) suitable for executing instructions. The host computer 3310 also includes software 3311, which is stored in the host computer 3310 or can be accessed by the host computer 3310 and can be executed by the processing circuit 3318. Software 3311 includes a host application 3312. The host application 3312 may be used to provide services to a remote user, such as a UE 3330 connected via an OTT connection 3350 terminated at the UE 3330 and the host 3310. In providing services to the remote user, the host application 3312 may provide user data sent using the OTT connection 3350.

[0193] The communication system 3300 also includes a base station 3320, which is provided in the telecommunication system and includes hardware 3325 that enables it to communicate with the host 3310 and the UE 3330. The hardware 3325 may include a communication interface 3326 for establishing and maintaining a wired or wireless connection with the interfaces of the different communication devices of the communication system 3300, and a communication interface 3326 for communicating with the coverage area ( Fig.15 3327 for establishing and maintaining at least a wireless connection 3370 for a UE 3330 in a communication interface 3326. The communication interface 3326 may be configured to facilitate a connection 3360 to a host computer 3310. The connection 3360 may be direct, or it may be through a core network ( Fig.15 3320) and / or through one or more intermediate networks external to the telecommunications system. In the illustrated embodiment, the hardware 3325 of the base station 3320 also includes processing circuitry 3328, which may include: one or more programmable processors, application specific integrated circuits, field programmable gate arrays, or a combination of these (not shown) adapted to execute instructions. The base station 3320 also has software 3321 stored internally or accessible via an external connection.

[0194] The communication system 3300 also includes the UE 3330 already mentioned. Its hardware 3335 may include a wireless interface 3337, which is configured to establish and maintain a wireless connection 3370 with a base station serving the coverage area where the UE 3330 is currently located. The hardware 3335 of the UE 3330 also includes a processing circuit 3338, which may include: one or more programmable processors suitable for executing instructions, a dedicated integrated circuit, a field programmable gate array, or a combination of these (not shown). The UE 3330 further includes software 3331, which is stored in the UE 3330 or can be accessed by the UE 3330 and can be executed by the processing circuit 3338. The software 3331 includes a client application 3332. The client application 3332 can be used to provide services to human or non-human users via the UE 3330 with the support of the host computer 3310. In the host computer 3310, the executing host application 3312 can communicate with the executing client application 3332 by terminating the OTT connection 3350 at the UE 3330 and the host computer 3310. In providing services to users, client application 3332 may receive request data from host application 3312 and provide user data in response to the request data. OTT connection 3350 may transmit both request data and user data. Client application 3332 may interact with the user to generate the user data it provides.

[0195] Notice, Fig.15 The host computer 3310, base station 3320 and UE 3330 shown can be connected with Fig.14 The host computer 3230, one of the base stations 3212a, 3212b, 3212c and one of the UEs 3291, 3292 are similar or identical to each other. That is, the internal workings of these entities can be as follows Fig.15 As shown, and independently, the surrounding network topology can be Fig.14 The surrounding network topology.

[0196] exist Fig.15 , an OTT connection 3350 has been abstractly drawn to illustrate communications between a host computer 3310 and a UE 3330 via a base station 3320, without explicit reference to any intermediate devices and the precise routing of messages via those devices. The network infrastructure may determine the routing, which may be configured to be hidden from the UE 3330 or from the service provider operating the host computer 3310, or from both. When the OTT connection 3350 is active, the network infrastructure may further make decisions by which it dynamically changes the routing (e.g., based on load balancing considerations or reconfiguration of the network).

[0197] The wireless connection 3370 between the UE 3330 and the base station 3320 is in accordance with the teachings of the embodiments described throughout this disclosure. One or more of the various embodiments use the OTT connection 3350 to improve the performance of the OTT service provided to the UE 3330, where the wireless connection 3370 forms the last leg. More specifically, the teachings of these embodiments can improve latency and thereby provide benefits such as reduced user waiting time.

[0198] The measurement process may be provided for the purpose of monitoring the data rate, latency and other factors improved by one or more embodiments. There may also be optional network functions for reconfiguring the OTT connection 3350 between the host computer 3310 and the UE 3330 in response to changes in the measurement results. The measurement process and / or network function for reconfiguring the OTT connection 3350 may be implemented in the software 3311 and hardware 3315 of the host computer 3310 or in the software 3331 and hardware 3335 of the UE 3330 or in both. In an embodiment, a sensor (not shown) may be deployed in or associated with a communication device through which the OTT connection 3350 passes; the sensor may participate in the measurement process by providing the values ​​of the monitoring quantities exemplified above or providing the values ​​of other physical quantities, and the software 3311, 3331 may calculate or estimate the monitoring quantities from the values ​​of other physical quantities. The reconfiguration of the OTT connection 3350 may include message formats, retransmission settings, preferred routes, etc.; the reconfiguration does not necessarily affect the base station 3320, and the base station 3320 may be unaware or imperceptible. Such processes and functions are known and practiced in the art. In certain embodiments, the measurements may involve proprietary UE signaling that facilitates host computer 3310 measurements of throughput, propagation time, latency, etc. The measurements may be implemented in software 3311 and 3331 that uses OTT connection 3350 to transmit messages (particularly empty messages or "dummy" messages) while software 3311 and 3331 monitors propagation time, errors, etc.

[0199] Fig.16 is a flow chart showing a method implemented in a communication system according to an embodiment. The communication system includes a host computer, a base station and a UE, which can be reference Fig.14 and Fig.15 For the sake of brevity of this disclosure, this section only includes references Fig.16. In step 3410, the host computer provides user data. In sub-step 3411 of step 3410 (which may be optional), the host computer provides the user data by executing a host application. In step 3420, the host computer initiates a transmission to the UE carrying the user data. In step 3430 (which may be optional), in accordance with the teachings of the embodiments described throughout the present disclosure, the base station sends the user data carried in the host-initiated transmission to the UE. In step 3440 (which may also be optional), the UE executes a client application associated with the host application executed by the host computer.

[0200] Fig.17 is a flow chart showing a method implemented in a communication system according to an embodiment. The communication system includes a host computer, a base station and a UE, which can be referred to with reference to FIGS. 13 and Fig.14 For the sake of brevity of this disclosure, only references to Fig.17 . In step 3510 of the method, the host computer provides user data. In an optional sub-step (not shown), the host computer provides the user data by executing a host application. In step 3520, the host computer initiates a transmission to the UE carrying the user data. According to the teachings of the embodiments described throughout the present disclosure, the transmission can be passed through a base station. In step 3530 (which may be optional), the UE receives the user data carried in the transmission.

[0201] Fig.18 is a flow chart showing a method implemented in a communication system according to an embodiment. The communication system includes a host computer, a base station and a UE, which can be reference Fig.15 For the sake of brevity of this disclosure, this section only includes references Fig.18 . In step 3610 (which may be optional), the UE receives input data provided by the host computer. Additionally or alternatively, in step 3620, the UE provides user data. In sub-step 3621 (which may be optional) of step 3620, the UE provides user data by executing a client application. In sub-step 3611 (which may be optional) of step 3610, the UE executes a client application that provides user data in response to received input data provided by the host computer. When providing user data, the executed client application may further consider user input received from the user. Regardless of the specific manner of providing user data, the UE initiates transmission of user data to the host computer in sub-step 3630 (which may be optional). In step 3640 of the method, in accordance with the teachings of the embodiments described throughout the present disclosure, the host computer receives user data sent from the UE.

[0202] Fig.19is a flow chart showing a method implemented in a communication system according to an embodiment. The communication system includes a host computer, a base station and a UE, which can be reference Fig.15 For the sake of brevity of this disclosure, this section only includes references Fig.19 In step 3710 (which may be optional), the base station receives user data from the UE in accordance with the teachings of the embodiments described throughout the present disclosure. In step 3720 (which may be optional), the base station initiates a transmission of the received user data to the host. In step 3730 (which may be optional), the host computer receives the user data carried in the transmission initiated by the base station.

[0203] According to one aspect of the present disclosure, there is provided a computer program product tangibly stored on a computer-readable storage medium and comprising instructions, which, when executed on at least one processor, cause the at least one processor to perform any one of the methods described above.

[0204] According to one aspect of the present disclosure, a computer-readable storage medium storing instructions is provided. When the instructions are executed by at least one processor, the instructions cause the at least one processor to perform any one of the methods described above.

[0205] Many advantages can be achieved by applying the proposed solutions according to embodiments of the present disclosure. For example, some embodiments provide new methods for indicating SSB by UE. Some embodiments provide new methods for determining the beam to be used for combined msgB transmission. Some embodiments provide new methods for determining the RNTI to be used for combined msgB transmission / monitoring. Some embodiments provide new methods for determining the MCS to be used for combined msgB transmission.

[0206] In addition, the present invention may also provide a carrier containing the above-mentioned computer program, wherein the carrier is one of an electronic signal, an optical signal, a radio signal or a computer-readable storage medium. The computer-readable storage medium may be, for example, an optical disc or an electronic storage device, such as a RAM (random access memory), a ROM (read-only memory), a flash memory, a magnetic tape, a CD-ROM, a DVD, a Blu-ray disc, etc.

[0207] The techniques described herein can be implemented in various ways so that the device that implements one or more functions of the corresponding device described with the embodiments includes not only prior art components, but also components for implementing one or more functions of the corresponding device described with the embodiments, and it can include separate components for each separate function or components that can be configured to perform two or more functions. For example, these techniques can be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or a combination thereof. For firmware or software, the implementation can be accomplished by modules (e.g., processes, functions, etc.) that perform the functions described herein.

[0208] Exemplary embodiments of the present invention have been described above with reference to the block diagrams and flowchart illustrations of the methods and apparatus. It will be understood that each block of the block diagrams and flowchart illustrations and combinations of blocks in the block diagrams and flowchart illustrations, respectively, can be implemented by various components including computer program instructions. These computer program instructions can be loaded onto a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine, whereby the instructions executed on the computer or other programmable data processing device create components for implementing the functions specified in the flowchart block or blocks.

[0209] In addition, although the operations are depicted in a particular order, this should not be understood as requiring that the operations be performed in the particular order shown or in sequence, or that all illustrated operations be performed to achieve the desired results. In some cases, multitasking and parallel processing may be advantageous. Similarly, although the above discussion contains several specific implementation details, these should not be interpreted as limitations on the scope of the subject matter described herein, but should be interpreted as descriptions of features that may be specific to a particular embodiment. Certain features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.

[0210] Although this specification contains many specific implementation details, these should not be interpreted as limitations on the scope of any implementation or the scope of what may be claimed, but rather should be interpreted as descriptions of features that may be specific to a particular embodiment of a particular implementation. Certain features described in this specification in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination. In addition, although the above-mentioned features may be described as working in certain combinations, or even initially claimed to be so protected, in some cases one or more features from the claimed combination may be deleted from the combination, and the claimed combination may be directed to a sub-combination or a variation of the sub-combination.

[0211] It is obvious to those skilled in the art that, as technology advances, the inventive concept can be implemented in various ways. The above embodiments are given for the purpose of describing rather than limiting the present disclosure, and it should be understood that, as those skilled in the art will readily appreciate, modifications and variations can be made without departing from the spirit and scope of the present disclosure. Such modifications and variations are considered to be within the scope of the present disclosure and the appended claims. The scope of protection of the present invention is defined by the appended claims.

Claims

1. A method (320) at a user equipment (UE), comprising: selecting (322) synchronization signals and physical broadcast channel blocks (SSBs) having signal measurement metrics that meet criteria; sending (324) a first message to a base station, the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH), wherein the RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity; as well as A second message is received (326) from the base station in response to the first message.

2. The method according to claim 1, wherein: The data includes information indicative of at least one SSB having the signal measurement metric satisfying the criterion.

3. The method according to claim 2, wherein: The at least one SSB indicated by the first message includes one or more SSBs associated with the RACH opportunity.

4. The method according to claim 2, wherein: The at least one SSB indicated by the first message includes an SSB in a set of SSBs having the signal measurement metric satisfying the criterion excluding an SSB indicated by the RACH preamble and the RACH opportunity.

5. The method according to any one of claims 1 to 4, wherein: The at least one SSB is indicated by a list ordered by the signal measurement metric or by a bitmap.

6. The method according to any one of claims 1 to 5, wherein: The RACH is a physical random access channel (PRACH), the USCH is a physical uplink shared channel (PUSCH), and the signal measurement metric is a reference signal received power (RSRP), or a reference signal received quality (RSRQ), or a signal to interference plus noise ratio (SINR) based on downlink signal measurement.

7. The method according to any one of claims 1 to 6, wherein: The criterion is that the signal measurement metric is greater than or not less than a threshold value.

8. The method according to any one of claims 1 to 7, wherein: The second message can multiplex respective responses to respective first messages of the UE and at least one other UE.

9. The method according to claim 8, wherein: The UE and the at least one other UE having the same determined MCS are multiplexed in the second message; The UE and the at least one other UE having a specific common SSB that satisfies the criterion are multiplexed in the second message; The UE and the at least one other UE that transmit the RACH preamble mapped to the same SSB are multiplexed in the second message; and / or The UE and the at least one other UE having the same downlink preferred beam are multiplexed in the second message.

10. The method according to claim 8 or 9, wherein: The beam used for the second message is one of the following: a common downlink beam for the UE and the at least one other UE; a beam covering at least one of the preferred beam of the UE and the preferred beam of the at least one other UE; A preferred beam of a UE having a higher priority between the UE and the at least one other UE; A beam randomly selected from the preferred beam of the UE and the preferred beam of the at least one other UE.

11. The method according to any one of claims 8 to 10, wherein: The Radio Network Temporary Identifier (RNTI) used for the second message is one of: A common RNTI for the UE and the at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and the at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of the at least one other UE; A UE-specific RNTI determined based on measurements of uplink signals from the UE and the at least one other UE or measurements of downlink signals by the UE and the at least one other UE.

12. The method according to claim 11, wherein: When the at least one other UE and the UE send the first message on the same RACH opportunity, calculating the common RNTI based on the same RACH opportunity, or The common RNTI is a group RNTI defined for the UE and the at least one other UE, or The common RNTI is indicated in respective first messages from the UE and the at least one other UE.

13. A method (720) at a base station, comprising: receiving (722) a first message from a user equipment (UE), the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH), wherein the RACH preamble or the RACH opportunity indicates an SSB selected by the UE based on a mapping of SSBs to the RACH preamble and the RACH opportunity; wherein the selected SSB has a signal measurement metric that satisfies a criterion; and A second message is sent (724) to the UE in response to the first message.

14. The method according to claim 13, wherein: The data includes information indicating at least one SSB having the signal measurement metric that meets the criterion, and the method further includes: based on the indication in the data, selecting a downlink beam for sending the second message to the UE.

15. A method (600) at a base station, comprising: receiving (602) a first message from a user equipment (UE), the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH); and sending (604) a second message as a respective response to the respective first messages of the UE and at least one other UE, The radio network temporary identifier (RNTI) used for the second message is one of the following: A common RNTI for the UE and the at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and the at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of the at least one other UE; A UE-specific RNTI determined based on measurements of uplink signals from the UE and the at least one other UE or measurements of downlink signals by the UE and the at least one other UE.

16. The method according to claim 15, wherein: When the at least one other UE and the UE send the first message on the same RACH opportunity, calculating the common RNTI based on the same RACH, or The common RNTI is a group RNTI defined for the UE and the at least one other UE, or The common RNTI is indicated in respective first messages from the UE and the at least one other UE.

17. An apparatus (800) at a user equipment (UE), comprising: Processor(821); as well as A memory (822) coupled to the processor (821), the memory (822) storing instructions executable by the processor (821), whereby the apparatus (800) is operable to: selecting a synchronization signal and a physical broadcast channel block (SSB) having a signal measurement metric that meets a standard; sending a first message to a base station, the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH), wherein the RACH preamble and the RACH opportunity are selected based on a mapping of the SSB to the RACH preamble and the RACH opportunity; as well as A second message is received from the base station in response to the first message.

18. The device according to claim 17, wherein: The apparatus is further operable to perform the method of any one of claims 2 to 12.

19. An apparatus (800) at a base station, comprising: Processor(821); and A memory (822) coupled to the processor (821), the memory (822) storing instructions executable by the processor (821), whereby the apparatus (800) is operable to: receiving a first message from a user equipment (UE), the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH), wherein the RACH preamble or the RACH opportunity indicates an SSB selected by the UE based on a mapping of SSBs to the RACH preamble and the RACH opportunity; wherein the selected SSB has a signal measurement metric that satisfies a criterion; and A second message is sent to the UE as a response to the first message.

20. The device according to claim 19, wherein The data includes information indicating at least one SSB having the signal measurement metric that meets the criterion, and the device further operates to select a downlink beam for sending the second message to the UE based on the indication in the data.

21. An apparatus (800) at a base station, comprising: Processor(821); as well as A memory (822) coupled to the processor (821), the memory (822) storing instructions executable by the processor (821), whereby the apparatus (800) is operable to: receiving a first message from a user equipment (UE), the first message comprising a random access channel (RACH) preamble on a RACH opportunity and data on an uplink shared channel (USCH); as well as sending a second message as a respective response to the respective first messages of the UE and at least one other UE, The radio network temporary identifier (RNTI) used for the second message is one of the following: A common RNTI for the UE and the at least one other UE; a UE-specific RNTI of a UE having a higher priority between the UE and the at least one other UE; a UE-specific RNTI randomly selected from the UE-specific RNTI of the UE and the UE-specific RNTI of the at least one other UE; A UE-specific RNTI determined based on measurements of uplink signals from the UE and the at least one other UE or measurements of downlink signals by the UE and the at least one other UE.

22. The device according to claim 21, wherein The apparatus is further operable to perform the method of claim 16.

23. A computer-readable storage medium storing instructions which, when executed by at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 16.

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