Schemes for RACH-less and RACH procedure
The innovative RACH-less and RACH resource allocation strategies optimize initial network access in communication systems by configuring RACH-LESS PUSCH resources and RNTI calculation, addressing efficiency and scalability challenges in TN/NTN scenarios.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-08-27
- Publication Date
- 2026-03-05
AI Technical Summary
Existing communication systems face challenges in efficiently establishing initial connections in scenarios like TN/NTN, particularly in the random access phase, where user equipment (UE) requires scalable and efficient RACH configurations to reduce latency and improve connection establishment.
The proposed solution involves innovative RACH-less and RACH resource allocation strategies, including RACH-LESS PUSCH resource configuration based on factors like beam index, repetition, OCC, frequency band, and group UE coverage index, along with RNTI calculation for contention-based and contention-free RACH-LESS PUSCH, and dynamic resource allocation for UEs with varying capabilities.
This approach enhances the efficiency and scalability of initial network access by optimizing resource allocation and reducing the need for traditional RACH procedures, thereby improving connection establishment in diverse scenarios.
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Figure CN2024114739_05032026_PF_FP_ABST
Abstract
Description
SCHEMES FOR RACH-LESS AND RACH PROCEDUREFIELD
[0001] This disclosure relates generally to wireless communications, and, more particularly, to methods and apparatus about procedures for schemes for RACH-less and RACH procedure related issues.BACKGROUND
[0002] In communication systems, the initial access process is a critical phase where a user equipment (UE) establishes a connection with the network. In order to have more scalable schemes for RACH-less and RACH procedure for different scenarios, like TN / NTN, new schemes for RACH-less and RACH procedure related designs can be considered.SUMMARY
[0003] The initial access process in communication system comprises two critical phases:
[0004] lCell Discovery and Downlink Synchronization: In this phase, UE scans the spectrum range for broadcast signals to detect available cells. The UE assesses these signals to select the most appropriate cell based on parameters such as signal quality and strength. Once a suitable cell is identified, the UE aligns its internal clocks with the cell's broadcast timing and frequency. This synchronization is crucial to ensure that the information transmitted by the cell can be accurately decoded by the UE.
[0005] lRandom Access Procedure: To establish an initial connection, the UE typically follows either a four-step or a two-step random access process. The four-step process is outlined as follows:
[0006] 1. The UE sends a preamble on the Random Access Channel (RACH) , signaling its request to connect to the network.
[0007] 2. The network acknowledges this preamble with a Random Access Response (RAR) ,which includes timing correction information and uplink resources for the UE to proceed.
[0008] 3. Leveraging allocated UL resources, the UE transmits a connection request, outlining its identity and reasons for initiating the connection.
[0009] 4. In response, the network finalizes the process with a contention resolution message that ensures the UE is uniquely identified and ready to proceed with an established Radio Resource Control (RRC) connection.
[0010] With these stages successfully completed, the UE transitions from the RACH procedure to a full-fledged RRC connection, laying the foundation for ongoing data communication within the network.
[0011] In communication systems, the initial access process is a critical phase where a user equipment (UE) establishes a connection with the network. In order to have more scalable RACH configuration for different scenarios, like TN / NTN, new RACH related designs can be considered. The random access procedure for initial connection in cellular networks usually involves the UE sending a preamble signal, receiving resources and timing information from the network, transmitting its connection request, and then receiving confirmation to finalize the connection with unique identification.
[0012] This invention is motivated by, but not limited to, an NTN scenario. In such a scenario, introducing innovative approaches on following aspects to boost the process's efficiency for user equipment's initial network access.
[0013] In an aspect of the disclosure, a method, a computer-readable medium, and an apparatus are provided. The apparatus may be a UE. The UE receives scalable configuration for RACH or RACH-LESS. The UE determines appropriate resource for RACH or RACH-LESS process.
[0014] To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed, and this description is intended to include all such aspects and their equivalents.BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 is a diagram illustrating an example of the Group UE coverage index.
[0016] Figure 2 is a diagram illustrating an example of the procedure of RACH-less and RACH procedure.
[0017] Figure 3 is a diagram illustrating an example of the procedure of RACH-less and RACH procedure.DETAILED DESCRIPTION
[0018] The detailed description set forth below in connection with the appended drawings is intended as a description of various configurations and is not intended to represent the only configurations in which the concepts described herein may be practiced. The detailed description includes specific details for the purpose of providing a thorough understanding of various concepts. However, it will be apparent to those skilled in the art that these concepts may be practiced without these specific details. In some instances, well known structures and components are shown in block diagram form in order to avoid obscuring such concepts.
[0019] Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively referred to as “elements” ) . These elements may be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system.
[0020] In communication systems, the initial access process is a critical phase where a user equipment (UE) establishes a connection with the network. In order to have more scalable RACH configuration for different scenarios, like TN / NTN, new RACH related designs can be considered. The random access procedure for initial connection in cellular networks usually involves the UE sending a preamble signal, receiving resources and timing information from the network, transmitting its connection request, and then receiving confirmation to finalize the connection with unique identification.
[0021] This invention is motivated by, but not limited to, an NTN scenario. In such a scenario, introducing innovative approaches on following aspects to boost the process's efficiency for user equipment's initial network access:
[0022] ·RACH-less and RACH resource allocation for ICS
[0023] ·RACH-less and RACH resource allocation update for connected state
[0024] ·RNTI of RACH-LESS PUSCH and RACH
[0025] ·RACH-less and RACH procedure
[0026] ·RACH-less configuration
[0027] ·RACH-LESS PUSCH complete message
[0028] More specifically, we propose to consider the following proposals:
[0029] Proposal#1: resource allocation of RACH-LESS PUSCH
[0030] RACH-LESS PUSCH resource allocation is configured with at least one of the following factors:
[0031] ·Beam index or SSB index
[0032] ·Repetition
[0033] ·With OCC or without OCC
[0034] ·Frequency band or GSCN
[0035] ·Group UE coverage index
[0036] ·frequency domain resource
[0037] ·time domain resource
[0038] For example, assume there are 16 RACH-LESS PUSCH resource sets in the total RACH-LESS PUSCH resource pool,
[0039] ·network can configure can allocate the 16 RACH-LESS PUSCH resource sets to 16 different beam indexes, where SSB beam index 1 corresponds to RACH-LESS PUSCH resource set 1.
[0040] ·or allocate the 16 RACH-LESS PUSCH resource sets to 16 different repetition numbers for RACH-LESS PUSCH, where RACH-LESS PUSCH with repetition 1 corresponds to RACH-LESS PUSCH resource set 1.
[0041] ·or allocate the 16 RACH-LESS PUSCH resource sets to 16 different OCC sequence, where OCC sequence [1 1 1 1] corresponds to RACH-LESS PUSCH resource set 1.
[0042] ·or allocate the 16 RACH-LESS PUSCH resource sets to different frequency band, where FR1 corresponds to RACH-LESS PUSCH resource set 1 and 2.
[0043] ·or allocate the 16 RACH-LESS PUSCH resource sets to different Group UE coverage index, where FR1 corresponds to RACH-LESS PUSCH resource set 1 and 2.
[0044] Note:
[0045] ·Different RACH-LESS PUSCH resource sets can be allocated by one or more of the above factors.
[0046] ·Different RACH-LESS PUSCH resource sets can be distinguished by at least one of: different frequency domain resource, different time domain resource, different space / beam domain resource. Different frequency domain resource can be indicated by different Offset_1 via SIB or RRC, and the Offset_1 indicates the offset of lowest RACH-LESS PUSCH resource transmission occasion in frequency domain with respective to PRB 0. Different time domain resource can be indicated by different RACH-LESS PUSCH resource time configuration index via SIB or RRC or MAC CE or DCI, and different RACH-LESS PUSCH resource time configuration index indicates different combination of start symbol and symbol length of RACH-LESS PUSCH , the RACH-LESS PUSCH resource time configuration index table can be predefined or RRC configured. Different space / beam domain resource can be indicated by Beam index or SSB index or Group UE coverage index, via SSB or SIB or RRC or MAC CE or DCI.
[0047] ·Different OCC sequence candidates can be configured by network with SIB and updated by RRC, UE can select different OCC.
[0048] Option #1: Beam index or SSB index or Group UE coverage index
[0049] For RACH-LESS PUSCH set #1with same frequency domain resource and same time domain resource, RACH-LESS PUSCH resource set #1 can be allocated to different space / beam domain. Network can configure separate parameters for time domain resource configuration, x, and frequency domain resource configuration, y, without consideration of space / beam domain, and / or network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xN, yN) } , for time domain resource configuration and frequency domain resource configuration with consideration of space / beam domain with index {1, 2, 3, …, N} , where xn can be same value as xp, ym can be same value as yq with n, p, m, q∈ {1, 2, 3, …, N} .
[0050] ·Note: If the field for a set of parameters { (x1, y1) , (x2, y2) , (x3, y3) , …, (xN, yN) } is present, the UE shall ignore separate parameters for time domain resource configuration x, and frequency domain resource configuration, y.
[0051] ·For example, one cell coverage comprises of 6 beams or 6 Group UE coverages with different Beam index or SSB index or Group UE coverage index, like index 1, 2, 3, 4, 5, 6 in the following figure. NW can configure RACH-LESS PUSCH resource set #1 to Index #1 and Index#6 to reduce interference and increase spectrum efficiency.
[0052] Table 1
[0053] Option #2: With OCC or without OCC
[0054] Network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xR, yR) } , for time domain resource configuration and frequency domain resource configuration with consideration of different repetition number {1, 2, 3, …, R} and without OCC, or network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xR, yR) } , for time domain resource configuration and frequency domain resource configuration with consideration of different repetition number {1, 2, 3, …, R} and with different OCC candidate.
[0055] ·Note: Whether OCC is enabled can be configured by SIB and can be updated by SIB / RRC / MAC CE. The OCC for preamble indication can be 1 bit to indicate whether OCC is enabled or not and the candidate sequence of OCC can be predefined for different RACH-LESS PUSCH repetition number. Or the OCC for preamble can be configured to indicate the candidate sequences of OCC for different RACH-LESS PUSCH repetition number, when the indication is configured, it implies that OCC of preamble is enabled.
[0056] Table 2
[0057] Proposal#2: RNTI of RACH-LESS PUSCH
[0058] RL-RNTI is the RNTI utilized for contention-based RACH-LESS PUSCH, while TC / C-RNTI can be utilized for contention-free RACH-LESS PUSCH. RL-RNTI can be 24-bit indicator or 16-bit indicator for CRC attachment with RNTI length indication information in MIB / SIB1, where RNTI length indication information is 1-bit indicator, when the indicator is 0 or default, the RNTI is 16-bit indicator, when the indicator is 1, the RNTI is 24-bit indicator. For RL-RNTI calculation: at least one of the following factors should be considered:
[0059] ·s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14)
[0060] ·t_id is the index of the first slot of the PRACH occasion in a system frame, where the subcarrier spacing to determine t_id is based on the value of μ specified in clause 5.3.2 in TS 38.211 [8] for μ = {0, 1, 2, 3} , and for μ = {5, 6} , t_id is the index of the 120 kHz slot in a system frame that contains the PRACH occasion (0 ≤ t_id < 80)
[0061] ·f_id is the index of the start RB of the BWP for RACH-LESS PUSCH in the frequency domain (0 ≤ f_id < 275 or 0 ≤ f_id < F_thr ) , F_thr can be predefined fixed value, it can be 8 / 16.
[0062] ·ul_carrier_id is the UL carrier used for Random Access Preamble transmission (0 for NUL carrier, and 1 for SUL carrier)
[0063] ·R_preamble is the repetition number for Random Access Preamble transmission (0 ≤ R_preamble < 8)
[0064] ·group_coverage_id is index for Group UE coverage for Random Access Preamble transmission (0 ≤ group_coverage_id < 100) , group_coverage_id is 0 for TN system
[0065] ·occ_id is index for different sequence of OCC for Random Access Preamble transmission (0 ≤ occ_id < 4) , group_coverage_id is 0 when no OCC is configured. G_factor =1 when group_coverage_id is 0, or G_factor =100 when group_coverage_id is not 0.
[0066] RL-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × F_thr × ul_carrier_id + 14 × 80 × F_thr × 2 ×R_preamble + 14 × 80 × F_thr × 2× 8 × group_coverage_id + 14 × 80 × F_thr × 2× 8 × G_factor × occ_id
[0067] Or RL-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × F_thr × ul_carrier_id Or RL-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × F_thr × ul_carrier_id + 14 × 80 × F_thr × 2 ×R_preamble
[0068] Or RL-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × F_thr × ul_carrier_id + 14 × 80 × F_thr × 2× group_coverage_id
[0069] Or RL-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × F_thr × ul_carrier_id + 14 × 80 × F_thr × 2× occ_id
[0070] Table 3
[0071] Table 4
[0072] Proposal#3: RNTI of RACH
[0073] RNTI can be 24-bit indicator or 16-bit indicator for CRC attachment with RNTI length indication information in MIB / SIB1, where RNTI length indication information is 1-bit indicator, when the indicator is 0 or default, the RNTI is 16-bit indicator, when the indicator is 1, the RNTI is 24-bit indicator. . For RA-RNTI / MSGB-RNTI calculation: at least one of the following factors should be considered:
[0074] ·s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14)
[0075] ·t_id is the index of the first slot of the PRACH occasion in a system frame, where the subcarrier spacing to determine t_id is based on the value of μ specified in clause 5.3.2 in TS 38.211 [8] for μ = {0, 1, 2, 3} , and for μ = {5, 6} , t_id is the index of the 120 kHz slot in a system frame that contains the PRACH occasion (0 ≤ t_id < 80)
[0076] ·f_id is the index of the PRACH occasion in the frequency domain (0 ≤ f_id < 8)
[0077] ·ul_carrier_id is the UL carrier used for Random Access Preamble transmission (0 for NUL carrier, and 1 for SUL carrier)
[0078] ·group_coverage_id is index for Group UE coverage for Random Access Preamble transmission (0 ≤ group_coverage_id < 100) , group_coverage_id is 0 for TN system
[0079] ·occ_id is index for different sequence of OCC for Random Access Preamble transmission (0 ≤ occ_id < 4) , group_coverage_id is 0 when no OCC is configured. G_factor =1 when group_coverage_id is 0, or G_factor =100 when group_coverage_id is not 0.
[0080] MSGB-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id + 14 × 80 × 8 × 2× group_coverage_id + 14 × 80 × 8 × 2× 100
[0081] OR MSGB-RNTI = 1 + s_id + 14 × t_id + 14 × 80 × f_id + 14 × 80 × 8 × ul_carrier_id + 14 × 80 × 8 × 2× group_coverage_id +14 × 80 × 8 × 2× G_factor × occ_id + 14 × 80 × 8 × 2× 100× 4
[0082] Table 5
[0083] Table 6
[0084] Proposal#4: RACH-less and RACH resource allocation for ICS
[0085] The System Information Block (SIB) directly allocates resources for both RACH-LESS and traditional RACH, enabling User Equipment (UE) with varying capabilities to select the appropriate resources. More capable users, such as those with a higher number of antennas in the Non-Terrestrial Network (NTN) environment like VSAT users, may opt for RACH-LESS resources that include Occupancy Code Channels (OCC) . Conversely, users with less capability, such as IoT / RedCap / handheld device users in NTN scenarios with fewer antennas, might choose the traditional RACH resources without OCC.
[0086] The allocates resources for both RACH-LESS and traditional RACH, enabling User Equipment (UE) with varying capabilities to select the appropriate resources, can be updated by RRC / MAC CE / DCI in RRC connected state. The update can be UE-specific or group_specific or beam-specific or cell-specific.
[0087] Proposal#5: RACH-less and RACH procedure
[0088] Network configures Cell / wide beam / group UE coverage specific resources for Msg1 / MsgA / RACH-less Msg3.
[0089] UE transmits RACH-less Msg3 wi / o OCC / NOMA with network configured resource.
[0090] UE decodes PDCCH for RACH-less Msg4 with RL-RNTI.
[0091] Once UE succussed to receive and decode RACH-less Msg4, UE transmits HARQ ACK for RACH-less Msg4 wi / o OCC / NOMA.
[0092] Once UE failed to receive or failed to decode RACH-less Msg4, UE incremented the number of UE failed times for RACH-LESS Msg3 with N. N_thr is the maximum number of consecutive failure times of RACH-LESS MSG3 procedure configured by network.
[0093] If N is not smaller than N_thr, fall-back RACH-based procedure is initialized;
[0094] UE transmits Msg1 / MsgA wi / o OCC / NOMA with network configured resource
[0095] If UE receives and decodes Msg2,
[0096] UE transmits Msg3 wi / o OCC / NOMA with configured resource
[0097] UE receives and decodes Msg4.
[0098] UE transmits HARQ ACK for Msg4 wi / o OCC / NOMA.
[0099] Else if UE receives and decodes MsgB.
[0100] UE transmits HARQ ACK for MsgB wi / o OCC / NOMA.
[0101] else, another RACH-LESS MSG3 procedure is restated.
[0102] Proposal#6: configuration of RACH-less PUSCH
[0103] The Network configures contention-based RACH-less PUSCH with SIB for serving cell with at lest one of the following:
[0104] ·Frequency hopping flag (1bit) : If the value of the frequency hopping flag is 0, the UE transmits the RACH-less PUSCH without frequency hopping; otherwise, the UE transmits the RACH-less PUSCH with frequency hopping.
[0105] ·RACH-less PUSCH frequency resource allocation (3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the index of the start RB of the BWP for RACH-LESS PUSCH in the frequency domain.
[0106] ·RACH-less PUSCH time resource allocation (3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the start (symbol / slot / subframe) and length (symbol / slot / subframe) of RACH-LESS PUSCH in the time domain.
[0107] ·RACH-less PUSCH format configuration (1 / 2 / 3 / 4 / 5 / 6 bits) : The configuration is utilize to indicate the PUSCH format for RACH-less PUSCH, different PUSCH format can have different CP length (normal / extended CP) , different PUSCH DMRS configuration, different repetition number, different frequency resources for RACH-less PUSCH (1 / 2 / 3 / 4PRB) .
[0108] ·Repetition (1 / 2 / 3bits) : Indicate the repetition number for RACH-LESS PUSCH.
[0109] ·MCS (4 / 5 / 6bits) : Indicate the MCS of RACH-LESS PUSCH.
[0110] ·Maximum Attempt for RACH-less PUSCH : This field provides the maximum number of consecutive failure times of RACH-LESS MSG3 procedure.
[0111] ·fallbackToRA (1bit) : This field indicates if a fallback procedure to four step / two step RACH is enabled.
[0112] ·RACH-less PUSCH SubcarrierSpacing Configuration (1 / 2 / 3 / 4 / 5 / 6bits) : This field indicates the SubcarrierSpacing for RACH-less PUSCH; when absent, 15KHz SCS is assumed.
[0113] ·transformPrecoder (1 / 2bits) : Enables the transform precoder for RACH-less PUSCH transmission, If the field is absent, the UE disables the transformer. Or the field indicates the transformPrecoder format utilized for RACH-less PUSCH.
[0114] ·RACH-less PUSCH TargetPower: The target power level at the network receiver side for RACH-less PUSCH. Or indicates the transmit power adjustment value of RACH-less PUSCH compared with selected SSB.
[0115] ·RACH-less PUSCH-ResponseWindow: RACH-less PUSCH-Response monitoring window length in number of slots / subframes.
[0116] Note:
[0117] The RACH-less PUSCH configuration with SIB can be utilized for initial access and in connected state when there is not dedicated RACH-less PUSCH configuration with dedicated RRC signalling.
[0118] Proposal#7: content of Msg4 of RACH-less Msg3
[0119] The content of Msg4 of RACH-less Msg3with at lest one of the following:
[0120] ·Timing Advance Command: The Timing Advance Command field indicates the index value TA used to control the amount of timing adjustment that the MAC entity has to apply. The size of the Timing Advance Command field is 12 / 13 bits;
[0121] ·RACH-LESS Msg3 identity: The identity associated with the RACH-LESS Msg3 transmission is identified, and the UE procedure continues as described in Proposal #5 when the UE Once UE succussed to receive and decode RACH-less Msg4
[0122] ·HACK-ACK enable / disable indication: Enables / disables the HACK-ACK transmission for Msg4 of RACH-less Msg3, If the field is absent, the UE enables the HACK-ACK transmission for Msg4 of RACH-less Msg3
[0123] ·OCC for HACK-ACK enable / disable indication: Enables / disables the OCC for HACK-ACK transmission for Msg4 of RACH-less Msg3, If the field is absent, the UE enables the OCC for HACK-ACK transmission for Msg4 of RACH-less Msg3 with OCC utilized for RACH-less Msg3.
[0124] ·PUCCH resource for HACK-ACK transmission for Msg4 of RACH-less Msg3: The transmission of the PUCCH is indicated by PUCCH resource indicator field of 4 bits.
[0125] ·PUCCH offset for HACK-ACK transmission for Msg4 of RACH-less Msg3: The transmission offset of the PUCCH is consisted of 4 bits.
[0126] The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects. Unless specifically stated otherwise, the term “some” refers to one or more. Combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as “at least one of A, B, or C, ” “one or more of A, B, or C, ” “at least one of A, B, and C, ” “one or more of A, B, and C, ” and “A, B, C, or any combination thereof” may be A only, B only, C only, A and B, A and C, B and C, or A and B and C, where any such combinations may contain one or more member or members of A, B, or C. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. The words “module, ” “mechanism, ” “element, ” “device, ” and the like may not be a substitute for the word “means. ” As such, no claim element is to be construed as a means plus function unless the element is expressly recited using the phrase “means for. ”
Claims
1.A method comprising RACH less and RACH procedure.2.The method of Claim 1, wherein RACH-LESS PUSCH resource allocation is configured with at least one of the following factors:·Beam index or SSB index·Repetition·With OCC or without OCC·Frequency band or GSCN·Group UE coverage index·frequency domain resource·time domain resource.3.The method of Claim 2, wherein for RACH-LESS PUSCH set #1with same frequency domain resource and same time domain resource, RACH-LESS PUSCH resource set #1 can be allocated to different space / beam domain, Network can configure separate parameters for time domain resource configuration, x, and frequency domain resource configuration, y, without consideration of space / beam domain, and / or network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xN, yN) } , for time domain resource configuration and frequency domain resource configuration with consideration of space / beam domain with index {1, 2, 3, …, N} , where xn can be same value as xp, ym can be same value as yq with n, p, m, q∈ {1, 2, 3, …, N} .4.The method of Claim 2, wherein Network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xR, yR) } , for time domain resource configuration and frequency domain resource configuration with consideration of different repetition number {1, 2, 3, …, R} and without OCC, or network can configure a set of parameters, { (x1, y1) , (x2, y2) , (x3, y3) , …, (xR, yR) } , for time domain resource configuration and frequency domain resource configuration with consideration of different repetition number {1, 2, 3, …, R} and with different OCC candidate.5.The method of Claim 1, when RL-RNTI is the RNTI utilized for contention-based RACH-LESS PUSCH, while TC / C-RNTI can be utilized for contention-free RACH-LESS PUSCH, RL-RNTI can be 24-bit indicator or 16-bit indicator for CRC attachment with RNTI length indication information in MIB / SIB1, where RNTI length indication information is 1-bit indicator, when the indicator is 0 or default, the RNTI is 16-bit indicator, when the indicator is 1, the RNTI is 24-bit indicator, for RL-RNTI calculation: at least one of the following factors should be considered:·s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14)·t_id is the index of the first slot of the PRACH occasion in a system frame, where the subcarrier spacing to determine t_id is based on the value of μ specified in clause 5.3.2 in TS 38.211 [8] for μ = {0, 1, 2, 3} , and for μ = {5, 6} , t_id is the index of the 120 kHz slot in a system frame that contains the PRACH occasion (0 ≤ t_id < 80)·f_id is the index of the start RB of the BWP for RACH-LESS PUSCH in the frequency domain (0 ≤ f_id < 275 or 0 ≤ f_id < F_thr) , F_thr can be predefined fixed value, it can be 8 / 16·ul_carrier_id is the UL carrier used for Random Access Preamble transmission (0 for NUL carrier, and 1 for SUL carrier)·R_preamble is the repetition number for Random Access Preamble transmission (0 ≤ R_preamble < 8)·group_coverage_id is index for Group UE coverage for Random Access Preamble transmission (0 ≤ group_coverage_id < 100) , group_coverage_id is 0 for TN system·occ_id is index for different sequence of OCC for Random Access Preamble transmission (0 ≤ occ_id < 4) , group_coverage_id is 0 when no OCC is configured, G_factor =1 when group_coverage_id is 0, or G_factor =100 when group_coverage_id is not 0.6.The method of Claim 1, when RNTI can be 24-bit indicator or 16-bit indicator for CRC attachment with RNTI length indication information in MIB / SIB1, where RNTI length indication information is 1-bit indicator, when the indicator is 0 or default, the RNTI is 16-bit indicator, when the indicator is 1, the RNTI is 24-bit indicator, for RA-RNTI / MSGB-RNTI calculation: at least one of the following factors should be considered:·s_id is the index of the first OFDM symbol of the PRACH occasion (0 ≤ s_id < 14)·t_id is the index of the first slot of the PRACH occasion in a system frame, where the subcarrier spacing to determine t_id is based on the value of μ specified in clause 5.3.2 in TS 38.211 [8] for μ = {0, 1, 2, 3} , and for μ = {5, 6} , t_id is the index of the 120 kHz slot in a system frame that contains the PRACH occasion (0 ≤ t_id < 80)·f_id is the index of the PRACH occasion in the frequency domain (0 ≤ f_id < 8)·ul_carrier_id is the UL carrier used for Random Access Preamble transmission (0 for NUL carrier, and 1 for SUL carrier)·group_coverage_id is index for Group UE coverage for Random Access Preamble transmission (0 ≤ group_coverage_id < 100) , group_coverage_id is 0 for TN system·occ_id is index for different sequence of OCC for Random Access Preamble transmission (0 ≤ occ_id < 4) , group_coverage_id is 0 when no OCC is configured, G_factor =1 when group_coverage_id is 0, or G_factor =100 when group_coverage_id is not 0.7.The method of Claim 1, wherein the System Information Block (SIB) directly allocates resources for both RACH-LESS and traditional RACH, enabling User Equipment (UE) with varying capabilities to select the appropriate resources, more capable users, such as those with a higher number of antennas in the Non-Terrestrial Network (NTN) environment like VSAT users, may opt for RACH-LESS resources that include Occupancy Code Channels (OCC) , conversely, users with less capability, such as IoT / RedCap / handheld device users in NTN scenarios with fewer antennas, might choose the traditional RACH resources without OCC.8.The method of Claim 1, wherein the allocates resources for both RACH-LESS and traditional RACH, enabling User Equipment (UE) with varying capabilities to select the appropriate resources, can be updated by RRC / MAC CE / DCI in RRC connected state, the update can be UE-specific or group_specific or beam-specific or cell-specific.9.The method of Claim 1, wherein the RACH-less and RACH procedure for initial access is:1>Network configures Cell / wide beam / group UE coverage specific resources for Msg1 / MsgA / RACH-less Msg3,1>UE transmits RACH-less Msg3 wi / o OCC / NOMA with network configured resource,1>UE decodes PDCCH for RACH-less Msg4 with RL-RNTI1>Once UE succussed to receive and decode RACH-less Msg4, UE transmits HARQ ACK for RACH-less Msg4 wi / o OCC / NOMA,1>Once UE failed to receive or failed to decode RACH-less Msg4, UE incremented the number of UE failed times for RACH-LESS Msg3 with N, N_thr is the maximum number of consecutive failure times of RACH-LESS MSG3 procedure configured by network,2>If N is not smaller than N_thr, fall-back RACH-based procedure is initialized;3>UE transmits Msg1 / MsgA wi / o OCC / NOMA with network configured resource;3> If UE receives and decodes Msg2;4>UE transmits Msg3 wi / o OCC / NOMA with configured resource4>UE receives and decodes Msg44>UE transmits HARQ ACK for Msg4 wi / o OCC / NOMA3> Else if UE receives and decodes MsgB4>UE transmits HARQ ACK for MsgB wi / o OCC / NOMA2>else, another RACH-LESS MSG3 procedure is restated.10.The method of Claim 1, wherein the Network configures contention-based RACH-less PUSCH with SIB for serving cell with at lest one of the following:·Frequency hopping flag (1bit) : If the value of the frequency hopping flag is 0, the UE transmits the RACH-less PUSCH without frequency hopping; otherwise, the UE transmits the RACH-less PUSCH with frequency hopping,·RACH-less PUSCH frequency resource allocation (3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the index of the start RB of the BWP for RACH-LESS PUSCH in the frequency domain,·RACH-less PUSCH time resource allocation (3 / 4 / 5 / 6 / 7 / 8bits) : Indicate the start (symbol / slot / subframe) and length (symbol / slot / subframe) of RACH-LESS PUSCH in the time domain,·RACH-less PUSCH format configuration (1 / 2 / 3 / 4 / 5 / 6 bits) : The configuration is utilize to indicate the PUSCH format for RACH-less PUSCH, different PUSCH format can have different CP length (normal / extended CP) , different PUSCH DMRS configuration, different repetition number, different frequency resources for RACH-less PUSCH (1 / 2 / 3 / 4PRB) ,·Repetition (1 / 2 / 3bits) : Indicate the repetition number for RACH-LESS PUSCH,·MCS (4 / 5 / 6bits) : Indicate the MCS of RACH-LESS PUSCH,·Maximum Attempt for RACH-less PUSCH : This field provides the maximum number of consecutive failure times of RACH-LESS MSG3 procedure,·fallbackToRA (1bit) : This field indicates if a fallback procedure to four step / two step RACH is enabled,·RACH-less PUSCH SubcarrierSpacing Configuration (1 / 2 / 3 / 4 / 5 / 6bits) : This field indicates the SubcarrierSpacing for RACH-less PUSCH; when absent, 15KHz SCS is assumed,·transformPrecoder (1 / 2bits) : Enables the transform precoder for RACH-less PUSCH transmission, If the field is absent, the UE disables the transformer, or the field indicates the transformPrecoder format utilized for RACH-less PUSCH,·RACH-less PUSCH TargetPower: The target power level at the network receiver side for RACH-less PUSCH, or indicates the transmit power adjustment value of RACH-less PUSCH compared with selected SSB,·RACH-less PUSCH-ResponseWindow: RACH-less PUSCH-Response monitoring window length in number of slots / subframes.11.The method of Claim 1, wherein the content of Msg4 of RACH-less Msg3with at lest one of the following:·Timing Advance Command: The Timing Advance Command field indicates the index value TA used to control the amount of timing adjustment that the MAC entity has to apply, the size of the Timing Advance Command field is 12 / 13 bits;·RACH-LESS Msg3 identity: The identity associated with the RACH-LESS Msg3 transmission is identified, and the UE procedure continues as described in Proposal #5 when the UE Once UE succussed to receive and decode RACH-less Msg4;·HACK-ACK enable / disable indication: Enables / disables the HACK-ACK transmission for Msg4 of RACH-less Msg3, If the field is absent, the UE enables the HACK-ACK transmission for Msg4 of RACH-less Msg3;·OCC for HACK-ACK enable / disable indication: Enables / disables the OCC for HACK-ACK transmission for Msg4 of RACH-less Msg3, If the field is absent, the UE enables the OCC for HACK-ACK transmission for Msg4 of RACH-less Msg3 with OCC utilized for RACH-less Msg3;·PUCCH resource for HACK-ACK transmission for Msg4 of RACH-less Msg3: The transmission of the PUCCH is indicated by PUCCH resource indicator field of 4 bits;·PUCCH offset for HACK-ACK transmission for Msg4 of RACH-less Msg3: The transmission offset of the PUCCH is consisted of 4 bits.
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