A method, apparatus, terminal and device for determining a random access channel occasion

Abstract

The application provides a random access channel occasion determination method, device, terminal and equipment, and relates to the technical field of communication. The method is applied to the terminal side, comprising receiving a downlink synchronization signal block (SSB) sent by a network side, wherein the downlink SSB carries an SSB index; receiving a random access channel (RACH) configuration indication index sent by the network side, wherein the RACH configuration indication index is used for indicating time domain position configuration information of an uplink random access channel occasion (RO) acquired by the terminal, and the SSB index is associated with the time domain position configuration information of the uplink RO; determining the time domain position of the uplink RO corresponding to the downlink SSB according to the SSB index and the RACH configuration indication index; wherein the transmission time of the downlink SSB of the same wave position and the reception time of the uplink RO have an offset value. The scheme of the application can avoid the problems of network unable to effectively allocate RO, terminal unable to use RO in the conventional way, and excessive resource waste caused by the excessively large air interface transmission delay in the non-terrestrial network (NTN).

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication technology, in particular to a method and device for determining a random access channel occasion, a terminal and equipment. BACKGROUND

[0002] To cope with the rapid growth of wireless data service demand and the challenges brought by new service demand, non-terrestrial networks (NTN) and satellite communication in particular have become an important technology in the field of mobile communication. When a terminal initiates a random access procedure, the satellite must receive the connection at a suitable random access occasion (RO) to complete the corresponding random access procedure. The random access procedure in NR uses beams, where the synchronization signal block (SSB) has multiple transmission opportunities in the time domain cycle and has a corresponding number, which can correspond to different beams. For the UE, only when the beam scanning signal of the SSB covers the UE, the UE has the opportunity to send the preamble. When the network receives the preamble of the UE, it knows the best downlink beam, in other words, it knows which beam points to the UE. Therefore, the SSB needs to be associated with the preamble, and the preamble is sent in the PRACH occasion, so the SSB is associated with the PRACH occasion.

[0003] However, due to the fact that the round-trip time (RTT) of the satellite-ground link is greater than the satellite beam scanning residence time, the current 5G NR allocation and determination of random access occasions will cause the terminal to be unable to obtain effective RO, and excessive resource waste due to the large RO window. SUMMARY

[0004] The purpose of the present application is to provide a method and device for determining a random access occasion, a terminal and equipment, which solves the problem that the current 5G NR allocation and determination of random access occasions will cause the terminal to be unable to obtain effective RO, and excessive resource waste due to the large RO window.

[0005] In a first aspect, to achieve the above-mentioned purpose, the embodiments of the present application provide a method for determining a random access channel occasion, applied to a terminal side, comprising:

[0006] receiving a downlink synchronization signal block (SSB) sent by a network side, wherein the downlink SSB carries an SSB index;

[0007] The terminal receives a Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0008] Based on the SSB index and the RACH configuration indication index, the time domain position of the uplink RO corresponding to the downlink SSB is determined; wherein, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO at the same frequency.

[0009] Secondly, to achieve the above objectives, embodiments of the present invention provide a method for determining the timing of a random access channel, applied to the network side, comprising:

[0010] Downlink synchronization signal blocks (SSBs) are sent to each wavelength position within the satellite coverage area, and the downlink SSBs carry SSB indexes;

[0011] Random Access Channel (RACH) configuration indication information is sent to each wave position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0012] There is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO at the same wavelength.

[0013] Thirdly, to achieve the above objectives, embodiments of the present invention provide a device for determining the timing of a random access channel, applied on the terminal side, comprising:

[0014] The first receiving module is used to receive downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index;

[0015] The second receiving module is used to receive the Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0016] The determining module is used to determine the time domain position of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index; wherein, there is an offset value between the transmission time of the downlink SSB and the reception time of the uplink RO at the same wavelength.

[0017] Fourthly, to achieve the above objectives, embodiments of the present invention provide a device for determining the timing of a random access channel, applied on the network side, comprising:

[0018] The first transmitting module is used to transmit downlink synchronization signal blocks (SSBs) to each wave position within the satellite coverage area, wherein the downlink SSBs carry an SSB index.

[0019] The second transmission module is used to transmit Random Access Channel (RACH) configuration indication information to each wave position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO), and the SSB index is associated with the time-domain location configuration information of the uplink RO. The transmission time of the downlink SSB and the reception time of the uplink RO at the same wave position have an offset value.

[0020] Fifthly, to achieve the above objectives, embodiments of the present invention provide a terminal, including: a transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; when the processor executes the program or instructions, it implements the method for determining the timing of random access channels as described in the first aspect.

[0021] Sixthly, to achieve the above objectives, embodiments of the present invention provide an access network device, including: a transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; when the processor executes the program or instructions, it implements the method for determining the timing of a random access channel as described in the second aspect.

[0022] In a seventh aspect, to achieve the above objectives, embodiments of the present invention provide a readable storage medium having a program or instructions stored thereon, which, when executed by a processor, implement the method for determining the timing of random access channels as described in the first or second aspect above.

[0023] The beneficial effects of the above-described technical solution of the present invention are as follows:

[0024] In the method of this invention, the terminal receives a downlink synchronization signal block (SSB) sent by the network side and obtains the SSB index carried by the downlink SSB; simultaneously, it receives a random access channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain position configuration information of the uplink random access channel (RO), and the SSB index is associated with the time-domain position configuration information of the uplink RO; furthermore, the terminal can determine the time-domain position of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index; wherein, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO in the same waveband position. In this way, by designing the uplink and downlink beam scanning time at the same beam camping position, the transmission waiting delay of uplink and downlink signaling (including RO) of users in the same waveband position can be reduced, avoiding the problems of the terminal being unable to obtain a valid RO due to the current 5G NR allocation and random access timing determination scheme, and excessive resource waste due to the RO window being too large. Attached Figure Description

[0025] Figure 1 This is a schematic diagram of ephemeris information according to an embodiment of the present invention;

[0026] Figure 2 This is one of the schematic diagrams illustrating the round-trip time (RTT) calculation according to an embodiment of the present invention;

[0027] Figure 3 This is one of the flowcharts for a method of determining the timing of a random access channel according to an embodiment of the present invention;

[0028] Figure 4 This is one of the schematic diagrams of uplink and downlink beam time-domain offset in an embodiment of the present invention;

[0029] Figure 5 This is the second schematic diagram of uplink and downlink beam time-domain offset according to an embodiment of the present invention;

[0030] Figure 6 This is a schematic diagram of RO distribution during the same residence time in an embodiment of the present invention;

[0031] Figure 7 This is a schematic diagram of the RO time-domain location determination process according to an embodiment of the present invention;

[0032] Figure 8 This is one of the schematic diagrams illustrating the correspondence between SSB and RO in an embodiment of the present invention;

[0033] Figure 9 This is the second schematic diagram illustrating the correspondence between SSB and RO in an embodiment of the present invention;

[0034] Figure 10 This is the third schematic diagram illustrating the correspondence between SSB and RO in an embodiment of the present invention;

[0035] Figure 11 This is a second flowchart of a method for determining the timing of a random access channel according to an embodiment of the present invention;

[0036] Figure 12 This is one of the structural diagrams of the random access channel timing determination device according to an embodiment of the present invention;

[0037] Figure 13 This is a second structural diagram of the device for determining the timing of a random access channel according to an embodiment of the present invention;

[0038] Figure 14 This is a schematic diagram of the hardware structure of the terminal according to an embodiment of the present invention;

[0039] Figure 15 This is a schematic diagram of the hardware structure of the access network device according to an embodiment of the present invention. Detailed Implementation

[0040] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0041] It should be understood that the phrase "one embodiment" or "an embodiment" throughout the specification means that a specific feature, structure, or characteristic related to the embodiment is included in at least one embodiment of the invention. Therefore, "in one embodiment" or "in an embodiment" appearing throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments.

[0042] In various embodiments of the present invention, it should be understood that the sequence number of each process described below does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0043] In addition, the terms "system" and "network" are often used interchangeably in this article.

[0044] In the embodiments provided in this application, it should be understood that "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean determining B solely based on A; B can also be determined based on A and / or other information.

[0045] Below, we will first give a brief introduction to the technical terms used in this application.

[0046] I. This application involves three parts in its satellite-to-ground link round-trip time (RTT) measurement: the maximum RTT (T) of the satellite coverage area. max ), RTT (T) at the sub-satellite pointmin ) and the actual RTT at the downlink receiving user ( Where i = 1, 2, ... represents the i-th SSB.

[0047] Among them, T max T min According to such Figure 2 The satellite beam depression angle θ, satellite altitude h, and constant Earth radius h shown in the ephemeris information are as follows: e The electromagnetic wave propagation speed c is calculated to obtain the specific result:

[0048] T max The calculation requires first calculating the geocentric angle. Then at this time T max The corresponding star-to-ground distance can be expressed as Then we can obtain and

[0049] The actual downlink receiving user like Figure 3 As shown, both the satellite and the user terminal (UE) obtain local time synchronization via the Global Navigation Satellite System (GNSS), with a time synchronization deviation set to E. At time t1, the satellite downlink scanning beam sends a Service Message Block (SSB) containing time information (timeInfo, which can explicitly or implicitly indicate the transmission time) to the UE. When the ground UE receives the SSB, it calculates the round-trip time (RTT) based on the time information contained within and the local reception time t2.

[0050] II. RACH Parameter Configuration

[0051] According to the RACH parameter reuse in the existing 5G protocol, its basic format is shown in the table below, that is, after the guard interval, a CP is added with a preamble sequence repeated several times.

[0052] CP leader sequence leader sequence ...... GT

[0053] 5G NR supports two main categories of channel formats: long and short. The sequence lengths used are 839 and 139, respectively. The long format channel format is only used for FR1, while the short format can be used for both FR1 and FR2. Therefore, since the short format channel format can support larger subcarrier spacing, it can better support high-speed scenarios and does not require cyclic shift constraints.

[0054] The cell coverage supported by each format is based on the CP length (T). CP Considering the round-trip maximum propagation delay and the multipath delay spread of the channel (T), P Based on calculations using the speed of light, the maximum cell radius = (T) CP-T P ) / κ×c / 2 where, κ=1 / 30.76×10 6 Second.

[0055] The present invention will now be described in detail through specific embodiments.

[0056] like Figure 3 As shown, an embodiment of the present invention provides a method for determining the timing of a random access channel, applied to the terminal side, comprising the following steps:

[0057] Step 101: Receive the downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index;

[0058] In this step, the SSB is sent to each position within the satellite coverage area by extending the SSB index.

[0059] For example, if there are I spherical positions within a satellite coverage area, labeled with spherical position ID i according to the scanning order, and i = 0, ..., I-1, and each spherical position's dwell time corresponds to L candidate SSBs, then the index of the first candidate SSB of the spherical position with ID i is i × L. This achieves a two-level SSB index: the first-level SSB index is equal to the spherical position ID, and the second-level SSB index indicates which candidate SSB is at which point in the spherical position's dwell time. The maximum number L of candidate SSBs is limited by the spherical position's dwell time. For the actual number of SSBs scheduled, each spherical position can be flexibly scheduled, and the number of scheduled SSBs is less than or equal to L.

[0060] To simplify the design, it can be assumed that the relative time of SSB transmission within each wavelength dwell time is fixed and unchanging. This relative time is relative to the initial time of the wavelength dwell time. The terminal, by default, receives SSBs within the wavelength dwell time according to the wavelength scan cycle.

[0061] It should be noted that in a satellite-to-ground system, the ground is covered by beam scanning. Within the satellite coverage area, there are I spectral positions, indexed as 0, ..., I-1, with each spectral position having a dwell time of T. b ms, beam scanning period is T period =I×T b .

[0062] Step 102: Receive the Random Access Channel (RACH) Configuration Indication Index (RACH Index) sent by the network side. The RACH Configuration Indication Index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0063] In this step, the association between the SSB index and the above includes: information in the time-domain location configuration information of the uplink RO that has a mapping relationship with the SSB index.

[0064] Step 103: Determine the time domain position of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index;

[0065] In this embodiment, based on the above embodiments, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO for the same wavelength. The transmission time of the downlink SSB refers to the time when the network side transmits the SSB, and the reception time of the uplink RO refers to the time when the network side receives the uplink RO.

[0066] like Figure 4 As shown, the uplink and downlink beam time-domain offsets within the corresponding wave position are designed as T. offset The offset value T offset It can be flexibly configured and broadcast to terminals via the network. In simplified scenarios, T offset Pre-configured on the base station and user side.

[0067] like Figure 5 As shown, based on this offset value, when the user equipment (UE) on the ground receives the downlink beam, it needs to perform actual RTT measurement based on the time information (timeInfo) contained therein. The reception delay of the downlink beam is thus determined. Where i = 1, 2, ..., represents the i-th RACH message. To ensure that the satellite receives the uplink message at the corresponding uplink beam scanning dwell time, the UE needs to consider the uplink propagation delay and the arrangement of the corresponding uplink beams. Therefore, the RACH message in this scheme needs to pause and wait. For the second SSB, the reception delay is... The waiting time is

[0068] In the above embodiments, the terminal receives the downlink synchronization signal block (SSB) sent by the network side and obtains the SSB index carried by the downlink SSB; simultaneously, it receives the random access channel (RACH) configuration indication index sent by the network side, so that the terminal can obtain the time-domain position configuration information of the uplink random access channel (RO) through the RACH configuration indication index, and the SSB index is associated with the time-domain position configuration information of the uplink RO; thus, the time-domain position of the uplink RO corresponding to the downlink SSB can be determined according to the SSB index and the RACH configuration indication index; wherein, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO in the same frequency position, so that by designing the uplink and downlink beam scanning time at the same beam camping position, the transmission waiting delay of uplink and downlink signaling (including RO) of users in the same frequency position can be reduced, avoiding the problems of the network being unable to effectively allocate RO and the terminal being unable to use RO in the conventional way due to the extremely large air interface transmission delay in the terrestrial network NTN, and the excessive resource waste caused by the RO window being too large.

[0069] In one specific embodiment, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0070] In this implementation, considering the time delay impact of the maximum satellite coverage band position's RTT, the uplink and downlink beam time domain offset within the corresponding band position is designed as T. offset In this way, the satellite can design the uplink and downlink beam scanning patterns in a more regular manner based on RTT measurements, and can avoid the problems caused by the large air interface transmission delay in the terrestrial network NTN, which leads to the network being unable to effectively allocate RO and the terminals being unable to use RO in the conventional way, as well as the waste of resources caused by the excessively large RO window.

[0071] In one embodiment, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0072] Based on the above embodiments, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is also related to at least one of the following:

[0073] Wave position dwell time T b ;

[0074] System frame number SFN at the start of the downlink beam scan period init ;

[0075] The format of the random access preamble;

[0076] The time-domain offset value T of the RO ro_offset ;

[0077] The offset value T offset .

[0078] For example, assume the initial downlink beam scan time is set to relative time 0 during the access process, and one scan cycle within the satellite coverage area is aligned with an integer number of SFN times (rounded up if there is a margin). In a satellite communication system, the subcarrier spacing is defined as Δf = 2. μ At 15kHz, based on the preamble format and the wavelength dwell time, the maximum number of RO time-domain locations within a single wavelength dwell time can be calculated. This allows for the further determination of the precise time-domain locations of multiple ROs within the wavelength dwell time. Specifically, determining the time-domain location of the ROs includes:

[0079] First, based on the preamble format of the random access preamble and the waveform dwell time T... b The residence time T of the wave position can be calculated. b Theoretically, this supports a maximum number M of RO time-domain locations, where, T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; in this embodiment, for T dur The setting is the total length of CP-OFDM and GT rounded down, i.e., T under Format 0, 1, 2, and 3. dur The lengths are 1ms, 3ms, 3.5ms, and 1ms respectively; while the short format has an integer number of symbols, as detailed in the table below:

[0080] Format A1 A2 A3 B1 B2 B3 B4 C0 C2 length symb 2 4 6 2 4 6 8 2 6

[0081] Secondly, such as Figure 6 As shown, the residence time T of wave position i b The number of RO time-domain locations within the range is Considering uplink and downlink beam scanning offset, the starting time (in ms) of the dwell time of beam position i is: T offset +i×T b ms;

[0082] The starting time (in ms) of the c-th RO is:

[0083] Where c∈{0,1,...,M-1},

[0084] As can be seen from the above embodiments, when T is known offset In the case of M, the start time of the c-th RO is related to the wave position ID and c; in the case of unknown Toffset And M, and assuming the initial downlink beam scan time is not the relative zero time of the access process, the starting time of the c-th RO is related to the wave position ID, c, T offset Wave position dwell time T b The system frame number (SFN) at the start of the downlink beam scan cycle. init The format of the random access preamble and the time-domain offset value T of the RO. ro_offset Related.

[0085] It should be noted that, as one implementation method, the format of the random access preamble can be indicated by the RACH configuration indicator index; or, when designing the RO layout, different T values ​​can be pre-selected and set. ro_offset M, PreambleFormat, to specify the time-domain offset of RO, the number of time-domain positions of RO, and the format.

[0086] The system frame number SFN at the start of the downlink beam scan period is mentioned above. init The network is updated at the beginning of each beam scan cycle.

[0087] It should be noted that SFN init The SFN is broadcast to the terminal from the network side, but not necessarily with every update. The terminal can use the previous or last SFN. init The SNF was calculated based on the scan period. init This is to avoid receiving delays.

[0088] Based on the above embodiments, the SSB index has a first mapping relationship with the wave position ID; the SSB index has a second mapping relationship with c.

[0089] For example, within a satellite coverage area, there are I spectral positions, numbered i according to the scanning order, where i = 0, ..., I-1. Each spectral position's dwell time corresponds to L candidate SSBs. Then, the index of the first candidate SSB for the spectral position with ID i is i×L; the index of the second candidate SSB is i×L+1; and the index of the Lth candidate SSB is i×L+L-1. Thus, the first mapping relationship between the SSB index and the spectral position ID is:

[0090] ssbindex mod L = i; where ssbindex is the wave position index, mod is the modulo operation, and i is the wave position ID. That is, the first-level SSB index (ssbindex mod L) can represent which candidate SSB in the wave position residence time.

[0091] In one embodiment, the second mapping relationship includes:

[0092] When the downlink SSB and the uplink RO have a one-to-many correspondence (ssb-perRACH-Occasion < 1),

[0093] When the downlink SSB and the uplink RO have a one-to-one correspondence (ssb-perRACH-Occasion=1),

[0094] When the downlink SSB and the uplink RO have a many-to-one correspondence (ssb-perRACH-Occasion>1),

[0095] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of transmissions within the same wavelength dwell time. One SSB, and It has a third mapping relationship with the SSB index; n f This indicates the number of frequency division multiplexing (FDM) types corresponding to message Msg1; c represents the dwell time T of the same frequency band. b The time-domain location of the c-th RO within the range.

[0096] For example, within a satellite coverage area, there are I spectral positions, numbered i according to the scanning order, where i = 0, ..., I-1. Each spectral position's dwell time corresponds to L candidate SSBs. Then, the index of the first candidate SSB for the spectral position with ID i is i×L; the index of the second candidate SSB is i×L+1; and the index of the Lth candidate SSB is i×L+L-1. Therefore, The third mapping relationship with the SSB index can be: in, This is a second-level SSB index used to represent the first wave position during the wave dwell time. One SSB.

[0097] In one specific embodiment, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0098] The system frame number is:

[0099] The subframe number is:

[0100] The time slot is:

[0101] The starting symbol is:

[0102] Among them, SFNinit The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0103] It should be noted that SFN here init and T offset All units are the same as those of the system frame SFN.

[0104] As an implementation approach, based on the above design and analysis, the time-domain location distribution columns of RO (RACH configuration indicator index, system frame number, subframe number, time slot, and start symbol) can be pre-configured in a table format on the base station and terminal side, and then informed to the user terminal through the RACH configuration indicator index during the access process.

[0105] The following example illustrates a specific configuration:

[0106] Example 1: Wave position dwell time is 1ms, T offset For 20ms, T dur It takes 1ms.

[0107] Configuration 1: Long format Format 0, subcarrier spacing 30kHz, M=1, T ro_offset =0.

[0108] In this configuration, only one RO time-domain position can be set for one wavelength dwell time, and T can be set. ro_offset =0, for the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0109] T offset +i×T b = (20+i)ms;

[0110] The start time of the upward RO is:

[0111]

[0112] The time-domain resource table for RO is as follows:

[0113]

[0114]

[0115] Among them, in the table (SFN) init +T offset )mod 1 024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0116] Configuration 2: Short format B4, subcarrier spacing 120kHz, M=10.

[0117] It can be calculated that there are 1×8×14=112 symbols within one wavelength dwell time. Theoretically, it supports a maximum of 14 RO time-domain positions. Setting 10 RO time-domain positions within one wavelength dwell time... satisfy

[0118] For the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0119] T offset +i×T b = (20+i)ms;

[0120] The start time of the upward RO is:

[0121]

[0122] The time-domain resource table for RO is as follows:

[0123]

[0124] Among them, (1) in the table above is:

[0125] In the table above, (2) is:

[0126] Among them, in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0127] The time slot where RO is located when c takes different values ​​is:

[0128]

[0129] The initial sign of RO is as follows when c takes different values:

[0130]

[0131] Configuration 3: Short format B4, subcarrier spacing 120kHz, M=13, T ro_offset =0ms.

[0132] It can be calculated that there are 1×8×14=112 symbols within one wavelength dwell time. Theoretically, a maximum of 14 RO time-domain positions can be arranged. Optionally, 13 RO time-domain positions can be configured within one wavelength dwell time. For the i-th wavelength, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelength dwell start time is:

[0133] T offset +i×T b = (20+i)ms;

[0134] The start time of the upward RO is:

[0135]

[0136] because Then T can be taken. ro_offset =0 symbols;

[0137] Its RO time-domain resource table is as follows:

[0138]

[0139]

[0140] Among them, (3) in the table above is:

[0141] Item (4) in the table above is:

[0142] Among them, in the table (SFN) init +T offset )mod 1 024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0143] When c takes different values, the time slot where RO is located is:

[0144]

[0145] When c takes different values, the starting sign of RO is:

[0146]

[0147] Therefore, in Example 1, the fixed RO time-domain resource table is as follows:

[0148]

[0149] Specifically, (1) in the table above refers to:

[0150] Specifically, (2) in the table above refers to:

[0151] Item (3) in the table above is specifically:

[0152] Item (4) in the table above is specifically:

[0153] Among them, in the table (SFN) init +T offset )mod 1 024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0154] Example 2: Wave position dwell time is 12ms, T offset For 20ms, T dur It takes 1ms.

[0155] Configuration 1: Long format Format 1, subcarrier spacing 30kHz, M=4, T ro_offset =0ms.

[0156] For the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0157] T offset +i×T b = (20+12i)ms;

[0158] The start time of the uplink RO is

[0159] The RO time-domain resource table is as follows:

[0160]

[0161] Among them, in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0162] Configuration 2: Long format Format 2, subcarrier spacing 120kHz, M=3, T ro_offset=0ms.

[0163] Under this configuration, there can be a maximum of 3 RO time-domain positions for one wavelength dwell time.

[0164] For the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0165] T offset +i×T b = (20+12i)ms;

[0166] The start time of the upward RO is:

[0167] The RO time-domain resource table is as follows:

[0168]

[0169]

[0170] Among them, in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0171] Therefore, in Example 2, the fixed RO time-domain resource table is as follows:

[0172]

[0173] Among them, in the table (SFN) init +T offset )mod 1 024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0174] Based on the above embodiments, it can be seen that in step 103, the time domain position of the uplink RO corresponding to the downlink SSB is determined according to the SSB index and the RACH configuration indication index. This can be referred to... Figure 7 As shown, the terminal first determines T. offset T ro_offset and SFN init The wave position ID is determined based on the SSB index, and c is further determined based on the SSB index and the correspondence between SSB and RO; the time domain position of RO can be determined by parsing the RACH configuration indication information indicated by prach-ConfigurationIndex.

[0175] In an optional embodiment, the terminal obtains the cell-specific random access parameter IE RACH-ConfigCommon by parsing System Information Block (SIB) information, including at least one of the following:

[0176] The totalNumberOfRA-Preambles is used to indicate the total number of Preambles used for contention- and non-contention-based random access in the RACH resource.

[0177] The ssb-perRACH-OccasionAndCB-PreamblesPerSSB is used to indicate the correspondence between SSB and RO and the number of competition-based Preambles for each SSB.

[0178] The RACH parameter set used for regular random access and beam fault recovery includes the following messages: prach-ConfigurationIndex for indicating the RO time-domain location configuration; msg1-FDM for indicating the Msg1 frequency division type; and msg1-FrequencyStart for indicating the frequency domain start position.

[0179] T used to indicate the time-domain offset of RO offset ;

[0180] SFN used to calculate the time-domain location of RO init ;

[0181] The correspondence between SSB and RO includes: one-to-one; one-to-many; and many-to-one.

[0182] It should be noted that the order in which SSBs are mapped to PRACH occasions should follow the following four requirements:

[0183] First, in a RO, the order of the preamble indexes is increasing;

[0184] Second, the frequency resource index order of frequency reuse RO is increasing;

[0185] Third, the order of the time-domain resource indexes of the time-domain multiplexed RO within the RACH time slot is increasing;

[0186] Fourth, the RACH slot index is in ascending order.

[0187] This scheme will be illustrated with a specific example. Suppose that there are 8 SSBs in a wavelength dwell time, and msgl-FDM=4, which means that the number of ROs in the frequency domain is 4.

[0188] Example 1

[0189] like Figure 8 As shown, it illustrates the one-to-many relationship between SSB and RO in a single wavelength dwell time slot. Specifically, ssb-perRACH-Occasion = 1 / 4, indicating that one SSB maps to four ROs. At the same time, msg1-FDM = 4, indicating that there are four frequency domain ROs on one time domain RO. Therefore, the four frequency domain ROs on the first time domain RO correspond to one SSB, the four frequency domain ROs on the second time domain RO correspond to another SSB, and so on.

[0190] Example 2

[0191] like Figure 9 As shown, this diagram illustrates the one-to-one relationship between SSBs and ROs in a single time slot. Specifically, ssb-perRACH-Occasion = 1, indicating that one SSB maps to one RO. Simultaneously, msg1-FDM = 4, indicating that there are four frequency domain ROs on one time domain RO. Therefore, the four frequency domain ROs on the first time domain RO each correspond to one SSB, which are SSBs 0 to 3. Since the number of SSBs is 8, the mapping is not yet complete. According to the SSB-RO mapping requirements, the four frequency domain ROs on the second time domain RO are mapped to SSBs 4 to 7 in an increasing order, and so on.

[0192] Example 3

[0193] like Figure 10 As shown, this diagram illustrates the many-to-one relationship between SSB and RO in a single wavelength dwell time slot. Specifically, ssb-perRACH-Occasion = 2, indicating that 2 SSBs map to 1 RO. Therefore, the mapping of the 4 frequency domain ROs on the first time domain RO is as follows: SSB 0 / 1 maps to RO 0, SSB2 / 3 maps to RO 1, SSB 4 / 5 maps to RO 2, SSB 6 / 7 maps to RO 3, and so on.

[0194] like Figure 11 As shown, this embodiment of the invention provides a method for determining the timing of a random access channel, applied to the network side, including:

[0195] Step 201: Send downlink synchronization signal blocks (SSBs) to each wavelength position within the satellite coverage area. The downlink SSBs carry SSB indexes.

[0196] It should be noted that in a satellite-to-ground system, the ground is covered by beam scanning. Within the satellite coverage area, there are I spectral positions, indexed as 0, ..., I-1, with each spectral position having a dwell time of T. b ms, beam scanning period is T period =I×T b.

[0197] In this step, the SSB is sent to each position within the satellite coverage area by extending the SSB index.

[0198] For example, if there are I spherical positions within a satellite coverage area, labeled with spherical position ID i according to the scanning order, and i = 0, ..., I-1, and each spherical position's dwell time corresponds to L candidate SSBs, then the index of the l-th candidate SSB of the spherical position with ID i is i × L. This allows for a two-level SSB index: the first-level SSB index is equal to the spherical position ID, and the second-level SSB index indicates which candidate SSB is at which point in the spherical position's dwell time. The maximum number L of candidate SSBs is limited by the spherical position's dwell time. For the actual number of SSBs scheduled, each spherical position can be flexibly scheduled, and the number of scheduled SSBs is less than or equal to L.

[0199] To simplify the design, it can be assumed that the relative time of SSB transmission within each wavelength dwell time is fixed and unchanging, and this relative time is relative to the initial time of the wavelength dwell time. The terminal receives SSBs by default with the wavelength dwell time as the period.

[0200] Step 201: Send Random Access Channel (RACH) configuration indication information to each wave position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0201] In this step, the association between the SSB index and the above includes: information in the time-domain location configuration information of the uplink RO that has a mapping relationship with the SSB index.

[0202] In this embodiment, based on the above embodiments, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO for the same wavelength. The transmission time of the downlink SSB refers to the time when the network side transmits the SSB, and the reception time of the uplink RO refers to the time when the network side receives the uplink RO.

[0203] like Figure 4 As shown, the uplink and downlink beam time-domain offsets within the corresponding wave position are designed as T. offset The offset value T offset It can be flexibly configured and broadcast to terminals via the network. In simplified scenarios, T offset Pre-configured on the base station and user side.

[0204] like Figure 5 As shown, based on this offset value, when the user equipment (UE) on the ground receives the downlink beam, it needs to perform actual RTT measurement based on the timeInfo information contained therein. The reception delay of the downlink beam is thus determined. Where i = 1, 2, ..., represents the i-th RACH message. To ensure that the satellite receives the uplink message at the corresponding uplink beam scanning dwell time, the UE needs to consider the uplink propagation delay and the arrangement of the corresponding uplink beams. Therefore, the RACH message in this scheme needs to pause and wait. For the second SSB, the reception delay is... The waiting time is

[0205] In the above embodiments, the network sends downlink synchronization signal blocks (SSBs) to each wavelength position within the satellite coverage area. Each downlink SSB carries an SSB index. The network also sends random access channel (RACH) configuration indication information to each wavelength position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. Thus, the terminal can determine the time-domain location of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index. There is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO for the same wavelength position. By designing the uplink and downlink beam scanning times at the same beam camping position with a delay, the transmission waiting latency of uplink and downlink signaling (including RO) for users within the same wavelength position can be reduced. This avoids the problems of terminals being unable to obtain effective ROs due to the current 5G NR allocation and random access timing determination scheme, and excessive resource waste due to excessively large RO windows.

[0206] In one specific embodiment, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0207] In this implementation, considering the time delay impact of the maximum satellite coverage band position's RTT, the uplink and downlink beam time domain offset within the corresponding band position is designed as T. offset In this way, the satellite can design the uplink and downlink beam scanning patterns in a more regular manner based on RTT measurements, and avoid the problems caused by the current 5G NR allocation and random access timing scheme, which may result in the terminal not being able to obtain an effective RO, and excessive resource waste due to an excessively large RO window.

[0208] In one embodiment, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0209] Based on the above embodiments, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is also related to at least one of the following:

[0210] Wave position dwell time T b ;

[0211] System frame number SFN at the start of the downlink beam scan period init ;

[0212] The format of the random access preamble;

[0213] The time-domain offset value T of the RO ro_offset ;

[0214] The offset value T offset .

[0215] For example, assuming the initial downlink beam scan time is set to relative time 0 during the access process, and one scan cycle within the satellite coverage area is aligned with an integer number of SFN times (rounded up if there is a margin), in a satellite communication system, the subcarrier spacing is defined as Δf = 2. μ At 15kHz, based on the preamble format and the preamp dwell time, the maximum number of RO time-domain positions within a preamp dwell time can be calculated. This allows for the further determination of the precise time-domain positions of multiple ROs within the preamp dwell time. Specifically, this includes:

[0216] First, based on the preamble format of the random access preamble and the waveform dwell time T... b The residence time T of the wave position can be calculated. b Theoretically, this supports a maximum number M of RO time-domain locations, where, T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; in this embodiment, for T dur The setting is the total length of CP-OFDM and GT rounded down, i.e., T under Format 0, 1, 2, and 3. dur The lengths are 1ms, 3ms, 3.5ms, and 1ms respectively; while the short format has an integer number of symbols, as detailed in the table below:

[0217] Format A1 A2 A3 B1 B2 B3 B4 C0 C2 length symb 2 4 6 2 4 6 8 2 6

[0218] Secondly, such as Figure 6 As shown, the residence time T of wave position i b The number of RO time-domain locations within the range is Considering uplink and downlink beam scanning offset, the starting time (in ms) of the dwell time of beam position i is: T offset +i×T b ms; then the starting time (in ms) of the c-th RO is:

[0219]

[0220] Where c∈{0,1,...,M-1},

[0221] As can be seen from the above embodiments, when T is known offset In the case of M, the start time of the c-th RO is related to the wave position ID and c; in the case of unknown T offset And C, and assuming the initial downlink beam scan time is not the relative zero time of the access process, the starting time of the c-th RO is related to the wave position ID, c, T. offset Wave position dwell time T b The system frame number (SFN) at the start of the downlink beam scan cycle. init The format of the random access preamble and the time-domain offset value T of the RO. ro_offset Related.

[0222] It should be noted that, as one implementation method, the format of the random access preamble can be indicated by the RACH configuration indicator index; or, when designing the RO layout, different T values ​​can be pre-selected and set. ro_offset M, PreambleFormat, to specify the time-domain offset of RO, the number of time-domain positions of RO, and the format.

[0223] The system frame number SFN at the start of the downlink beam scan period is mentioned above. init The network is updated at the beginning of each beam scan cycle.

[0224] It should be noted that SFN init The network broadcasts the update to the terminal, but not necessarily with every update. The terminal can refer to the previous SFN. init The SNF was calculated based on the scan period. init This is to avoid receiving delays.

[0225] Based on the above embodiments, the SSB index has a first mapping relationship with the wave position ID; the SSB index has a second mapping relationship with c.

[0226] For example, within a satellite coverage area, there are I spectral positions, numbered i according to the scanning order, where i = 0, ..., I-1. Each spectral position's dwell time corresponds to L candidate SSBs. Then, the index of the l-th candidate SSB for the spectral position with ID i is i×L; the index of the 2nd candidate SSB is i×L+1; and the index of the L-th candidate SSB is i×L+L-1. Thus, the SSB index and the spectral position ID have the following first mapping relationship:

[0227] ssbindex mod L = i; where ssbindex is the wave position index, mod is the modulo operation, and i is the wave position ID. That is, the first-level SSB index (ssbindex mod L) can represent which candidate SSB in the wave position residence time.

[0228] In one embodiment, the second mapping relationship includes:

[0229] When the downlink SSB and the uplink RO have a one-to-many correspondence (ssb-perRACH-Occasion < 1),

[0230] When the downlink SSB and the uplink RO have a one-to-one correspondence (ssb-perRACH-Occasion=1),

[0231] When the downlink SSB and the uplink RO have a many-to-one correspondence (ssb-perRACH-Occasion>1),

[0232] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of transmissions within the same wavelength dwell time. One SSB, and It has a third mapping relationship with the SSB index; n f This indicates the number of frequency division multiplexing (FDM) types corresponding to message Msg1; c represents the dwell time T of the same frequency band. b The time-domain location of the c-th RO within the range.

[0233] For example, within a satellite coverage area, there are I spectral positions, numbered i according to the scanning order, where i = 0, ..., I-1. Each spectral position's dwell time corresponds to L candidate SSBs. Then, the index of the first candidate SSB for the spectral position with ID i is i×L; the index of the second candidate SSB is i×L+1; and the index of the Lth candidate SSB is i×L+L-1. Therefore, The third mapping relationship with the SSB index can be: in, This is a second-level SSB index used to represent the first wave position during the wave dwell time. One SSB.

[0234] In one specific embodiment, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0235] The system frame number is:

[0236] The subframe number is:

[0237] The time slot is:

[0238] The starting symbol is:

[0239] Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0240] It should be noted that SFN here init and T offset All units are the same as those of the system frame SFN.

[0241] As an implementation approach, based on the above design and analysis, the time-domain location distribution columns of RO (RACH configuration indicator index, system frame number, subframe number, time slot, and start symbol) can be pre-configured in a table format on the base station and terminal side, and then informed to the user terminal through the RACH configuration indicator index during the access process.

[0242] The following example illustrates a specific configuration:

[0243] Example 1: Wave position dwell time is 1ms, T offset For 20ms, T dur It takes 1ms.

[0244] Configuration 1: Long format Format 0, subcarrier spacing 30kHz, M=1, T ro_offset =0.

[0245] In this configuration, only one RO time-domain position can be set for one wavelength dwell time, and T can be set. ro_offset =0, for the i-th wave position, the starting time of the upward wave position residence is:

[0246] T offset +i×T b = (20+i)ms;

[0247] The start time of the upward RO is:

[0248]

[0249] The time-domain resource table for RO is as follows:

[0250]

[0251] Among them, in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0252] Configuration 2: Short format B4, subcarrier spacing 120kHz, M=10.

[0253] It can be calculated that there are 1×8×14=112 symbols within one wavelength dwell time. Theoretically, it supports a maximum of 14 RO time-domain positions. Setting 10 RO time-domain positions within one wavelength dwell time... satisfy

[0254] For the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0255] T offset +i×T b = (20+i)ms;

[0256] The start time of the upward RO is:

[0257]

[0258] The time-domain resource table for RO is as follows:

[0259]

[0260] Among them, (1) in the table above is:

[0261] In the table above, (2) is:

[0262] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0263] The time slot where RO is located when c takes different values ​​is:

[0264]

[0265] The initial sign of RO is as follows when c takes different values:

[0266]

[0267] Configuration 3: Short format B4, subcarrier spacing 120kHz, M=13, T ro_offset =0ms.

[0268] It can be calculated that there are 1×8×14=112 symbols within one wavelength dwell time. Theoretically, a maximum of 14 RO time-domain positions can be arranged. Optionally, 13 RO time-domain positions can be configured within one wavelength dwell time. For the i-th wavelength, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelength dwell start time is:

[0269] T offset +i×T b = (20+i)ms;

[0270] The start time of the upward RO is:

[0271]

[0272] because Then T can be taken. ro_offset =0 symbols;

[0273] Its RO time-domain resource table is as follows:

[0274]

[0275] Among them, (3) in the table above is:

[0276] Item (4) in the table above is:

[0277] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0278] When c takes different values, the time slot where RO is located is:

[0279]

[0280] When c takes different values, the starting sign of RO is:

[0281]

[0282] Therefore, in Example 1, the fixed RO time-domain resource table is as follows:

[0283]

[0284] Specifically, (1) in the table above refers to:

[0285] Specifically, (2) in the table above refers to:

[0286] Item (3) in the table above is specifically:

[0287] Item (4) in the table above is specifically:

[0288] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0289] Example 2: Wave position dwell time is 12ms, T offset For 20ms, T dur It takes 1ms.

[0290] Configuration 1: Long format Format 1, subcarrier spacing 30kHz, M=4, T ro_offset =0ms.

[0291] For the i-th wavelet, assuming the initial downlink beam scanning time is set to the relative 0 time of the access process, the uplink wavelet dwell start time is:

[0292] T offset +i×T b = (20+12i)ms;

[0293] The start time of the upward RO is then...

[0294] The RO time-domain resource table is as follows:

[0295]

[0296] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0297] Configuration 2: Long format Format 2, subcarrier spacing 120kHz, M=3, T ro_offset =0ms.

[0298] Under this configuration, a single uplink beam position can have a maximum of three RO time-domain locations. For the i-th beam position, assuming the initial downlink beam scan time is set to the relative 0 time of the access process, the uplink beam position dwell start time is:

[0299] T offset +i×T b = (20+12i)ms;

[0300] The starting time of the upward RO is:

[0301] The RO time-domain resource table is as follows:

[0302]

[0303] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0304] Therefore, in Example 2, the fixed RO time-domain resource table is as follows:

[0305]

[0306] It should be noted that in the table (SFN) init +T offset )mod 1024 is the starting frame number of the uplink RO cycle, T offset It is an integer ms, with the same unit as SFN.

[0307] Based on the above embodiments, it can be seen that in step 103, the time domain position of the uplink RO corresponding to the downlink SSB is determined according to the SSB index and the RACH configuration indication index. This can be referred to... Figure 7 As shown, the terminal first determines T. offset T ro_offset and SFN init The wave position ID is determined based on the SSB index, and c is further determined based on the SSB index and the correspondence between SSB and RO; the time domain position of RO can be determined by parsing the RACH configuration indication information indicated by prach-ConfigurationIndex.

[0308] In an optional embodiment, the terminal obtains the cell-specific random access parameter IE RACH-ConfigCommon by parsing System Information Block (SIB) information, including at least one of the following:

[0309] The totalNumberOfRA-Preambles is used to indicate the total number of Preambles used for contention- and non-contention-based random access in the RACH resource.

[0310] The term ssb-perRACH-OccasionAndCB-PreamblesPerSSB is used to indicate the correspondence between SSB and RO and the number of competition-based preambles for each SSB.

[0311] The RACH parameter set used for regular random access and beam fault recovery includes the following messages: prach-ConfigurationIndex for indicating the RO time-domain location configuration; msgl-FDM for indicating the Msg1 frequency division type; and msg1-FrequencyStart for indicating the frequency domain start position.

[0312] T used to indicate the time-domain offset of RO offset ;

[0313] SFN used to calculate the time-domain location of RO init ;

[0314] The correspondence between SSB and RO includes: one-to-one; one-to-many; and many-to-one.

[0315] It should be noted that the order in which SSBs are mapped to PRACH occasions should follow the following four requirements:

[0316] First, in a RO, the order of the preamble indexes is increasing;

[0317] Second, the frequency resource index order of frequency reuse RO is increasing;

[0318] Third, the order of the time-domain resource indexes of the time-domain multiplexed RO within the RACH time slot is increasing;

[0319] Fourth, the RACH slot index is in ascending order.

[0320] This scheme will be illustrated with a specific example. Suppose that there are 8 SSBs in a wavelength dwell time, and msg1-FDM=4, which means that the number of ROs in the frequency domain is 4.

[0321] Example 1

[0322] like Figure 8 As shown, it illustrates the one-to-many relationship between SSB and RO in a single wavelength dwell time slot. Specifically, ssb-perRACH-Occasion = 1 / 4, indicating that one SSB maps to four ROs. At the same time, msg1-FDM = 4, indicating that there are four frequency domain ROs on one time domain RO. Therefore, the four frequency domain ROs on the first time domain RO correspond to one SSB, the four frequency domain ROs on the second time domain RO correspond to another SSB, and so on.

[0323] Example 2

[0324] like Figure 9 As shown, S illustrates the one-to-one relationship between SSB and RO in a wave position dwell time slot. Specifically, ssb-perRACH-Occasion = 1, indicating that one SSB maps to one RO. At the same time, msg1-FDM = 4, indicating that there are 4 frequency domain ROs on one time domain RO. Therefore, the 4 frequency domain ROs on the first time domain RO correspond to one SSB, which are SSB 0 to 3. Since the number of SSBs is 8, the mapping is not yet complete. According to the SSB and RO mapping requirements, the 4 frequency domain ROs on the second time domain RO are mapped to SSBs 4 to 7 in an increasing order, and so on.

[0325] Example 3

[0326] like Figure 9 As shown, this diagram illustrates the many-to-one relationship between SSB and RO in a single wavelength dwell time slot. Specifically, ssb-perRACH-Occasion = 2, indicating that 2 SSBs map to 1 RO. Therefore, the mapping of the four frequency domain ROs on the first time domain RO is as follows: SSB 0 / 1 maps to RO 0, SSB 2 / 3 maps to RO 1, SSB 4 / 5 maps to RO 2, SSB 6 / 7 maps to RO 3, and so on.

[0327] like Figure 12 As shown, an embodiment of the present invention provides a random access channel timing determination device 1200, applied to the terminal side, comprising:

[0328] The first receiving module 1201 is used to receive a downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index.

[0329] The second receiving module 1202 is used to receive a Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO), and the SSB index is associated with the time-domain location configuration information of the uplink RO.

[0330] The determining module 1203 is used to determine the time domain position of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index; wherein, there is an offset value between the transmission time of the downlink SSB and the reception time of the uplink RO at the same wavelength.

[0331] Optionally, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0332] Optionally, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0333] Optionally, the SSB index has a first mapping relationship with the wave position ID;

[0334] The SSB index has a second mapping relationship with c.

[0335] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following:

[0336] Wave position dwell time T b ;

[0337] System frame number SFN at the start of the downlink beam scan period init；

[0338] The format of the random access preamble;

[0339] The time-domain offset value of the RO Tro_offset ;

[0340] The offset value T offset .

[0341] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0342] The system frame number is:

[0343] The subframe number is:

[0344] The time slot is:

[0345] The starting symbol is:

[0346] Among them, SFN init The system frame number at the start of the downlink beam scan period; T offsetThe offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0347] Optionally, the second mapping relationship includes:

[0348] In the case where the downlink SSB and the uplink RO have a one-to-many correspondence,

[0349] In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO,

[0350] In the case where the downlink SSB and the uplink RO have a many-to-one correspondence,

[0351] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of transmissions within the same wavelength dwell time. One SSB, and It has a third mapping relationship with the SSB index; n f This indicates the number of frequency division multiplexing (FDM) types corresponding to message Msg1; c represents the dwell time T of the same frequency band. b The time-domain location of the c-th RO within the range.

[0352] Optionally, the system frame number SFN at the start of the downlink beam scanning period. init The network is updated at the beginning of each beam scan cycle.

[0353] The random access channel timing determination device in this embodiment obtains the downlink SSB index by receiving the downlink synchronization signal block (SSB) sent by the network side; simultaneously, it receives the random access channel configuration indication index (RACH) sent by the network side, so that the terminal can obtain the time-domain position configuration information of the uplink random access channel timing (RO) through the RACH configuration indication index, and the SSB index is associated with the time-domain position configuration information of the uplink RO; thus, the time-domain position of the uplink RO corresponding to the downlink SSB can be determined according to the SSB index and the RACH configuration indication index; wherein, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO in the same waveband, so that by designing the uplink and downlink beam scanning time at the same beam camping position, the transmission waiting delay of uplink and downlink signaling (including RO) of users in the same waveband can be reduced, avoiding the problems of the terminal not being able to obtain a valid RO due to the current 5G NR allocation and random access timing determination scheme, and excessive resource waste due to the RO window being too large.

[0354] like Figure 13 As shown, an embodiment of the present invention provides a random access channel timing determination device 1300, applied on the network side, comprising:

[0355] The first transmitting module 1301 is used to transmit downlink synchronization signal blocks (SSBs) to each wave position within the satellite coverage area, wherein the downlink SSBs carry an SSB index.

[0356] The second transmitting module 1302 is used to transmit Random Access Channel (RACH) configuration indication information to each wave position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO), and the SSB index is associated with the time-domain location configuration information of the uplink RO. The transmission time of the downlink SSB and the reception time of the uplink RO at the same wave position have an offset value.

[0357] Optionally, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0358] Optionally, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0359] Optionally, the SSB index has a first mapping relationship with the wave position ID;

[0360] The SSB index has a second mapping relationship with c.

[0361] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following:

[0362] Wave position dwell time T b ;

[0363] System frame number SFN at the start of the downlink beam scan period init ;

[0364] The format of the random access preamble;

[0365] The time-domain offset value T of the RO ro_offset ;

[0366] The offset value T offset .

[0367] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0368] The system frame number is:

[0369] The subframe number is:

[0370] The time slot is:

[0371] The starting symbol is:

[0372] Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, week T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0373] Optionally, the second mapping relationship includes:

[0374] In the case where the downlink SSB and the uplink RO have a one-to-many correspondence,

[0375] In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO,

[0376] In the case where the downlink SSB and the uplink RO have a many-to-one correspondence,

[0377] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of waves transmitted during the dwell time of the wave position. One SSB, and It has a third mapping relationship with the SSB index; n f Msg1 represents the number of frequency division multiplexing units corresponding to the frequency division multiplexing type; c represents the dwell time T of the same wavelength. b The time-domain location of the c-th RO within the range.

[0378] Optionally, the system frame number SFN at the start of the downlink beam scanning period. init It is updated by the satellite at the beginning of each beam scan cycle.

[0379] The random access channel timing determination device in this embodiment sends downlink synchronization signal blocks (SSBs) to each band position within the satellite coverage area. The downlink SSBs carry an SSB index. It also sends random access channel (RACH) configuration indication information to each band position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel timing (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. Thus, the terminal can determine the time-domain location of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index. There is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO for the same band position. By designing the uplink and downlink beam scanning times at the same band position with a delay, the transmission waiting delay of uplink and downlink signaling (including RO) for users within the same band position can be reduced. This avoids the problems of the current 5G NR allocation and random access timing determination scheme causing the terminal to be unable to obtain a valid RO, and excessive resource waste due to an excessively large RO window.

[0380] Another embodiment of the present invention includes a terminal, such as Figure 14 As shown, it includes a transceiver 1410, a processor 1400, a memory 1420, and a program or instructions stored in the memory 1420 and executable on the processor 1400; when the processor 1400 executes the program or instructions, it performs the following steps:

[0381] Receive downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index;

[0382] The terminal receives a Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0383] Based on the SSB index and the RACH configuration indication index, the time domain position of the uplink RO corresponding to the downlink SSB is determined; wherein, there is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO at the same frequency.

[0384] The transceiver 1410 is used to receive and send data under the control of the processor 1400.

[0385] Among them, Figure 14 In this context, the bus architecture can include any number of interconnected buses and bridges, specifically linking various circuits together, such as one or more processors represented by processor 1400 and memory represented by memory 1420. The bus architecture can also link together various other circuits, such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. Transceiver 1410 can be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over a transmission medium. For different user equipment, user interface 1430 can also be an interface capable of connecting external or internal devices, including but not limited to keypads, displays, speakers, microphones, joysticks, etc.

[0386] The processor 1400 is responsible for managing the bus architecture and general processing, while the memory 1420 can store the data used by the processor 1400 when performing operations.

[0387] Optionally, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0388] Optionally, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0389] Optionally, the SSB index has a first mapping relationship with the wave position ID;

[0390] The SSB index has a second mapping relationship with c.

[0391] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following:

[0392] Wave position dwell time T b ;

[0393] System frame number SFN at the start of the downlink beam scan period init ;

[0394] The format of the random access preamble;

[0395] The time-domain offset value T of the RO ro_offset ;

[0396] The offset value T offset .

[0397] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0398] The system frame number is:

[0399] The subframe number is:

[0400] The time slot is:

[0401] The starting symbol is:

[0402] Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0403] Optionally, the second mapping relationship includes:

[0404] In the case where the downlink SSB and the uplink RO have a one-to-many correspondence,

[0405] In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO,

[0406] In the case where the downlink SSB and the uplink RO have a many-to-one correspondence,

[0407] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of transmissions within the same wavelength dwell time. One SSB, and It has a third mapping relationship with the SSB index; n f This indicates the number of frequency division multiplexing (FDM) types corresponding to message Msg1; c represents the dwell time T of the same frequency band. b The time-domain location of the c-th RO within the range.

[0408] Optionally, the system frame number SFN at the start of the downlink beam scanning period. init The network is updated at the beginning of each beam scan cycle.

[0409] Another embodiment of the access network device of the present invention, such as Figure 15 As shown, it includes a transceiver 1510, a processor 1500, a memory 1520, and a program or instructions stored in the memory 1520 and executable on the processor 1500; when the processor 1500 executes the program or instructions, it performs the following steps:

[0410] Downlink synchronization signal blocks (SSBs) are sent to each wavelength position within the satellite coverage area, and the downlink SSBs carry SSB indexes;

[0411] Random Access Channel (RACH) configuration indication information is sent to each wave position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO.

[0412] There is an offset between the transmission time of the downlink SSB and the reception time of the uplink RO at the same wavelength.

[0413] The transceiver 1510 is used to receive and send data under the control of the processor 1500.

[0414] Among them, Figure 15In this context, the bus architecture may include any number of interconnected buses and bridges, specifically linking various circuits together, represented by one or more processors (processor 1500) and memory (memory 1520). The bus architecture may also link together various other circuits such as peripheral devices, voltage regulators, and power management circuits, which are well known in the art and therefore will not be described further herein. The bus interface provides an interface. The transceiver 1510 may be multiple elements, including transmitters and receivers, providing a unit for communicating with various other devices over a transmission medium. The processor 1500 is responsible for managing the bus architecture and general processing, and the memory 1520 may store data used by the processor 1500 during operation.

[0415] Optionally, the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

[0416] Optionally, the time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

[0417] Optionally, the SSB index has a first mapping relationship with the wave position ID;

[0418] The SSB index has a second mapping relationship with c.

[0419] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following:

[0420] Wave position dwell time T b ;

[0421] System frame number SFN at the start of the downlink beam scan period init ;

[0422] The format of the random access preamble;

[0423] The time-domain offset value T of the RO ro_offset ;

[0424] The offset value T offset .

[0425] Optionally, the time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes:

[0426] The system frame number is:

[0427] The subframe number is:

[0428] The time slot is:

[0429] The starting symbol is:

[0430] Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

[0431] Optionally, the second mapping relationship includes:

[0432] In the case where the downlink SSB and the uplink RO have a one-to-many correspondence,

[0433] In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO,

[0434] In the case where the downlink SSB and the uplink RO have a many-to-one correspondence,

[0435] Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of waves transmitted during the dwell time of the wave position. One SSB, and It has a third mapping relationship with the SSB index; n f Msg1 represents the number of frequency division multiplexing units corresponding to the frequency division multiplexing type; c represents the dwell time T of the same wavelength. b The time-domain location of the c-th RO within the range.

[0436] Optionally, the system frame number SFN at the start of the downlink beam scanning period. init It is updated by the satellite at the beginning of each beam scan cycle.

[0437] This invention provides a readable storage medium storing a program or instructions. When executed by a processor, the program or instructions implement the steps in the method for determining the timing of a random access channel as described above, achieving the same technical effect. To avoid repetition, further details are omitted here. The computer-readable storage medium may include read-only memory (ROM), random access memory (RAM), a magnetic disk, or an optical disk.

[0438] It should be further noted that the terminals described in this specification include, but are not limited to, smartphones, tablets, etc., and many of the functional components described are referred to as modules in order to emphasize the independence of their implementation.

[0439] In this embodiment of the invention, the module can be implemented in software so that it can be executed by various types of processors. For example, an identified executable code module may include one or more physical or logical blocks of computer instructions, which may be constructed as objects, procedures, or functions. Nevertheless, the executable code of the identified module does not need to be physically located together, but may include different instructions stored in different bits, which, when logically combined, constitute the module and achieve the module's intended purpose.

[0440] In practice, an executable code module can be a single instruction or many instructions, and can even be distributed across multiple different code segments, different programs, and across multiple memory devices. Similarly, operational data can be identified within the module and can be implemented in any suitable form and organized within any suitable type of data structure. This operational data can be collected as a single dataset or distributed across different locations (including different storage devices), and can exist, at least in part, solely as electronic signals within the system or network.

[0441] When a module can be implemented using software, considering the current level of hardware technology, modules that can be implemented in software can be implemented using hardware circuits by those skilled in the art to achieve the corresponding functions, without considering cost. These hardware circuits include conventional very-large-scale integrated circuits (VLSI) or gate arrays, as well as existing semiconductors such as logic chips and transistors, or other discrete components. Modules can also be implemented using programmable hardware devices, such as field-programmable gate arrays, programmable array logic, and programmable logic devices.

[0442] The exemplary embodiments described above are with reference to the accompanying drawings. Many different forms and embodiments are feasible without departing from the spirit and teachings of the invention. Therefore, the invention should not be construed as limiting the exemplary embodiments set forth herein. Rather, these exemplary embodiments are provided to make the invention complete and convey the scope of the invention to those skilled in the art. In these drawings, component dimensions and relative dimensions may be exaggerated for clarity. The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. As used herein, unless clearly indicated otherwise, the singular forms “a,” “an,” and “the” are intended to include all such forms. It will be further understood that the terms “comprising” and / or “including”, when used in this specification, indicate the presence of the stated features, integers, steps, operations, components, and / or elements, but do not exclude the presence or addition of one or more other features, integers, steps, operations, components, and / or groups thereof. Unless otherwise indicated, when stated, a range of values ​​includes the upper and lower limits of the range and any subranges in between.

[0443] The above description represents the preferred embodiments of the present invention. It should be noted that those skilled in the art can make various improvements and modifications without departing from the principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for determining the timing of a random access channel, characterized in that, Applied to the terminal side, including: Receive downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index; The terminal receives a Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. Based on the SSB index and the RACH configuration indication index, the time domain position of the uplink RO corresponding to the downlink SSB is determined; wherein, there is an offset value between the transmission time of the downlink SSB and the reception time of the uplink RO at the same frequency. The offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

2. The method for determining the timing of a random access channel according to claim 1, characterized in that, The time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

3. The method for determining the timing of a random access channel according to claim 2, characterized in that, The SSB index and the wave position ID have a first mapping relationship; The SSB index has a second mapping relationship with c.

4. The method for determining the timing of a random access channel according to claim 2, characterized in that, The time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following: Wave position dwell time T b ; System frame number SFN at the start of the downlink beam scan period init ; The format of the random access preamble; The time-domain offset value T of the RO ro_offset ; The offset value T offset .

5. The method for determining the timing of a random access channel according to claim 4, characterized in that, The time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes: The system frame number is: The subframe number is: The time slot is: The starting symbol is: Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

6. The method for determining the timing of a random access channel according to claim 3, characterized in that, The second mapping relationship includes: In the case where the downlink SSB and the uplink RO have a one-to-many correspondence, In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO, In the case where the downlink SSB and the uplink RO have a many-to-one correspondence, Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of transmissions within the same wavelength dwell time. One SSB, and It has a third mapping relationship with the SSB index; n f This indicates the number of frequency division multiplexing (FDM) types corresponding to message Msg1; c represents the dwell time T of the same frequency band. b The time-domain location of the c-th RO within the range.

7. The method for determining the timing of a random access channel according to claim 4, characterized in that, The system frame number SFN at the start of the downlink beam scan period init The network is updated at the beginning of each beam scan cycle.

8. A method for determining the timing of a random access channel, characterized in that, Applied to the network side, including: Downlink synchronization signal blocks (SSBs) are sent to each wavelength position within the satellite coverage area, and the downlink SSBs carry SSB indexes; The Random Access Channel (RACH) configuration indication index is sent to each position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. Among them, there is an offset value between the transmission time of the downlink SSB and the reception time of the uplink RO at the same wavelength; The offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

9. The method for determining the timing of a random access channel according to claim 8, characterized in that, The time-domain position of the uplink RO indicated in the time-domain position configuration information of the RO is related to the wave position ID and c; wherein, c represents the time-domain position of the c-th RO within the same wave position dwell time.

10. The method for determining the timing of a random access channel according to claim 9, characterized in that, The SSB index has a first mapping relationship with the wave position ID; The SSB index has a second mapping relationship with c.

11. The method for determining the timing of a random access channel according to claim 9, characterized in that, The time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO is also related to at least one of the following: Wave position dwell time T b ; System frame number SFN at the start of the downlink beam scan period init ; The format of the random access preamble; The time-domain offset value T of the RO ro_offset ; The offset value T offset .

12. The method for determining the timing of a random access channel according to claim 11, characterized in that, The time-domain location of the uplink RO indicated in the time-domain location configuration information of the RO includes: The system frame number is: The subframe number is: The time slot is: The starting symbol is: Among them, SFN init The system frame number at the start of the downlink beam scan period; T offset The offset value is denoted by i; i is the wave position ID; T is the offset value. b M is the residence time of the wavelet; T is the residence time of the wavelet. b The number of RO time-domain locations configured internally, and T dur For the duration of RO, and the T dur It is related to the format of the random access preamble; the c represents the dwell time T of the same wavelet. b The time-domain location of the c-th RO within T; ro_offset is the time-domain offset value of RO; μ is the subcarrier spacing configuration parameter.

13. The method for determining the timing of a random access channel according to claim 10, characterized in that, The second mapping relationship includes: In the case where the downlink SSB and the uplink RO have a one-to-many correspondence, In the case where there is a one-to-one correspondence between the downlink SSB and the uplink RO, In the case where the downlink SSB and the uplink RO have a many-to-one correspondence, Where N represents the number of ROs corresponding to one SSB; P represents the number of SSBs corresponding to one RO; Indicates the number of waves transmitted during the dwell time of the wave position. One SSB, and It has a third mapping relationship with the SSB index; n f Msg1 represents the number of frequency division multiplexing units corresponding to the frequency division multiplexing type; c represents the dwell time T of the same wavelength. b The time-domain location of the c-th RO within the range.

14. The method for determining the timing of a random access channel according to claim 11, characterized in that, The system frame number SFN at the start of the downlink beam scan period init It is updated by the satellite at the beginning of each beam scan cycle.

15. A device for determining the timing of a random access channel, characterized in that, Applied to the terminal side, including: The first receiving module is used to receive downlink synchronization signal block (SSB) sent by the network side, wherein the downlink SSB carries an SSB index; The second receiving module is used to receive the Random Access Channel (RACH) configuration indication index sent by the network side. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. The determining module is used to determine the time domain position of the uplink RO corresponding to the downlink SSB based on the SSB index and the RACH configuration indication index; wherein, there is an offset value between the transmission time of the downlink SSB and the reception time of the uplink RO at the same frequency, and the offset value is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

16. A device for determining the timing of a random access channel, characterized in that, Applied to the network side, including: The first transmitting module is used to transmit downlink synchronization signal blocks (SSBs) to each wave position within the satellite coverage area, wherein the downlink SSBs carry an SSB index. The second transmission module is used to transmit a Random Access Channel (RACH) configuration indication index to each band position within the satellite coverage area. The RACH configuration indication index is used to instruct the terminal to obtain the time-domain location configuration information of the uplink random access channel (RO). The SSB index is associated with the time-domain location configuration information of the uplink RO. The transmission time of the downlink SSB and the reception time of the uplink RO at the same band position have an offset value, which is greater than or equal to the maximum round-trip time (RTT) within the network coverage area.

17. A terminal, comprising: A transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; characterized in that, when the processor executes the program or instructions, it implements the method for determining the timing of a random access channel as described in any one of claims 1-7.

18. An access network device, comprising: A transceiver, a processor, a memory, and a program or instructions stored in the memory and executable on the processor; characterized in that, when the processor executes the program or instructions, it implements the method for determining the timing of a random access channel as described in any one of claims 8-14.

19. A readable storage medium having a program or instructions stored thereon, characterized in that, When the program or instructions are executed by the processor, they implement the method for determining the timing of a random access channel as described in any one of claims 1-14.

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