CN117750534A

CN117750534A - PRACH repeated transmission method, device, system and computer readable storage medium

Info

Publication number: CN117750534A
Application number: CN202211102453.6A
Authority: CN
Inventors: 李南希; 朱剑驰; 尹航; 佘小明; 陈鹏
Original assignee: China Telecom Corp Ltd
Current assignee: China Telecom Corp Ltd
Priority date: 2022-09-09
Filing date: 2022-09-09
Publication date: 2024-03-22
Also published as: WO2024051392A1

Abstract

The disclosure provides a PRACH repeated transmission method, a device, a system and a computer readable storage medium, and relates to the technical field of wireless communication, wherein the method comprises the following steps: at least one first time machine configured for PRACH repeat transmission, each first time machine comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bundled with the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

Description

PRACH repeated transmission method, device, system and computer readable storage medium

Technical Field

The present disclosure relates to the field of wireless communications technologies, and in particular, to a method, an apparatus, a system, and a computer readable storage medium for repeated transmission of a physical random access channel (Physical Random Access Channel, PRACH).

Background

The 3GPP NR Realease-17 protocol does not yet support repeated transmission of PRACH. According to the current protocol version, a User Equipment (UE) calculates a Random Access radio network temporary identifier (RA-RNTI) according to a PRACH transmission occasion of transmitting a preamble, and listens to a physical downlink control channel (Physical Downlink Control Channel, PDCCH) within a Random Access response (Random Access Response, RAR) time window. If the RA-RNTI is adopted to successfully descramble the monitored downlink control information (Downlink Control Information, DCI), and a random access preamble identifier (Random Access Preamble Identifier, RAPID) corresponding to a preamble sent by the carrying UE is received according to the dispatching of the DCI, the PRACH transmission is proved to be successful; if not successful, the UE needs to re-perform PRACH transmission, which not only causes additional delay, but also wastes PRACH transmission resources.

Disclosure of Invention

The inventors have noted that to achieve PRACH retransmission, PRACH transmission resources need to be configured for PRACH retransmission. If the existing PRACH transmission resources for PRACH single transmission are multiplexed, the probability of PRACH transmission collision is increased; if a complete set of PRACH transmission resources dedicated to PRACH retransmission is reconfigured, resource waste is caused.

In order to solve the above-described problems, the embodiments of the present disclosure propose the following solutions.

According to an aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission method, applied to a network side, including: at least one first time machine configured for PRACH repeat transmission, each first time machine comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bundled with the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

In some embodiments, the method further comprises: PRACH detection is carried out on any first occasion to obtain a first preamble of repeated transmission of the UE; determining an RA-RNTI according to a second PRACH transmission occasion in the random first occasion; scrambling the first DCI by utilizing the RA-RNTI to obtain a second DCI; and sending the second DCI and RAR scheduled by the second DCI, wherein the RAR carries the RAID of the first preamble.

In some embodiments, the one or more sets of second PRACH transmission occasions include a first set of second PRACH transmission occasions and a second set of second PRACH transmission occasions other than the first set of second PRACH transmission occasions, the one second PRACH transmission occasion belonging to the first set of second PRACH transmission occasions, the one second PRACH transmission occasion being different from the second set of second PRACH transmission occasions.

In some embodiments, the one second PRACH transmission occasion is a first second PRACH transmission occasion or a last second PRACH transmission occasion of the first set of second PRACH transmission occasions.

In some embodiments, the first PRACH transmission occasion is different in time domain from each second PRACH transmission occasion in each first occasion.

In some embodiments, at least one of the one or more sets of second PRACH transmission occasions comprises a plurality of second PRACH transmission occasions that do not overlap each other in the time domain.

In some embodiments, the method further comprises: at least one second occasion configured for a single transmission of the PRACH, each second occasion comprising a first PRACH transmission occasion, the second set of preambles associated with the second occasion being different from the first set of preambles associated with each first occasion.

In some embodiments, the method further comprises: and configuring the association relation between each first occasion and the SSB index of the synchronous signal block, wherein in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions are associated with the same one or more SSB indexes.

In some embodiments, the method further comprises: and sending the radio resource control information to inform the UE whether the network side starts PRACH repeated transmission.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission method, applied to a network side, including: the configuration information includes first indication information indicating at least one first time machine for PRACH repeated transmission, each first time machine including a first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, the first PRACH transmission opportunity also being for PRACH single transmission.

According to still another aspect of the embodiments of the present disclosure, there is provided a method for PRACH retransmission, applied to a UE, including: receiving configuration information of PRACH, wherein the configuration information comprises first indication information, the first indication information indicates at least one first time machine used for PRACH repeated transmission, each first time machine comprises a first PRACH transmission time and one or more groups of second PRACH transmission time bound with the first PRACH transmission time, and the first PRACH transmission time is also used for PRACH single transmission; determining a first occasion from the at least one first occasion; and repeating the transmission of the first preamble on the first occasion.

In some embodiments, the determining a first time from the at least one first occasion comprises: determining a first occasion from the at least one first occasion when a first condition is satisfied, the first condition including: and knowing that the network side starts PRACH repeated transmission.

In some embodiments, the determining a first time from the at least one first occasion comprises: determining the PRACH repeated transmission times; and determining the first opportunity according to the PRACH repeated transmission times.

In some embodiments, the determining the number of PRACH retransmissions comprises: and determining the PRACH repeated transmission times according to at least one of the received power of the received downlink signal and the path loss of the downlink.

In some embodiments, the larger the received power, the smaller the PRACH repeat transmission number.

In some embodiments, the smaller the path loss, the smaller the PRACH retransmission number.

In some embodiments, the total number of PRACH transmission occasions in the one first occasion and the number of PRACH repeated transmissions are the same, and the repeating transmission of the first preamble on the one first occasion includes: and repeatedly transmitting the first preamble on a first PRACH transmission occasion and a second PRACH transmission occasion in the first occasion.

In some embodiments, the configuration information further includes third indication information, where the third indication information is used to indicate an association relationship between each first occasion and SSB indexes, and in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions associate the same one or more SSB indexes; said determining a first time instant from said at least one first time instant comprises: determining a first transmission PRACH transmission occasion associated with the SSB index selected by the UE as a candidate first PRACH transmission occasion; determining one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a second condition as the one first occasion, wherein the second condition includes: the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is equal to the number of PRACH retransmissions minus one.

In some embodiments, the number of second PRACH transmission occasions in the one first occasion is the same as the number of PRACH repeated transmissions, and the repeating transmission of the first preamble on the one first occasion includes: the first preamble is repeatedly transmitted on a second PRACH transmission occasion of the one first occasion.

In some embodiments, the configuration information further includes third indication information, where the third indication information is used to indicate an association relationship between each first occasion and SSB indexes, and in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions associate the same one or more SSB indexes; said determining a first time instant from said at least one first time instant comprises: determining a first transmission PRACH transmission occasion associated with the SSB index selected by the UE as a candidate first PRACH transmission occasion; determining one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a third condition as the one first occasion, wherein the third condition includes: the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is the same as the number of PRACH repeated transmissions.

In some embodiments, the configuration information further includes fourth indication information indicating second occasions for a single transmission of the PRACH, each second occasion including a first PRACH transmission occasion, the second set of preambles associated with the second occasion being different from the first set of preambles associated with each first occasion.

In some embodiments, the method further comprises: receiving a second DCI; determining an RA-RNTI according to a second PRACH transmission occasion in the first occasions; descrambling the second DCI by utilizing the RA-RNTI to obtain first DCI; and receiving RAR according to the first DCI.

In some embodiments, the method further comprises: and executing a subsequent random access procedure under the condition that the RAR carries the RAID of the first preamble.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission apparatus, applied to a network side, including: a configuration module configured to configure at least one first time machine for PRACH repeat transmission, each first time machine comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bound to the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission apparatus, applied to a network side, including: a memory; and a processor coupled to the memory and configured to perform the method of any of the embodiments described above based on instructions stored in the memory.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission apparatus, applied to a UE, including: a receiving module configured to receive configuration information of a PRACH, wherein the configuration information includes first indication information indicating at least one first time machine for PRACH retransmission, each first time machine including a first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, the first PRACH transmission opportunity further being for PRACH single transmission; and a transmission module configured to repeat transmission of the preamble on the one first occasion.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission apparatus, applied to a UE, including: a memory; and a processor coupled to the memory and configured to perform the method of any of the embodiments described above based on instructions stored in the memory.

According to a further aspect of the embodiments of the present disclosure, a base station is provided, including any one of the foregoing apparatuses described in the embodiments applied to a network side.

According to a further aspect of the embodiments of the present disclosure, there is provided a user equipment, including an apparatus as described in any one of the embodiments above applied to a UE.

According to still another aspect of the embodiments of the present disclosure, there is provided a PRACH retransmission system, including: the base station and the user equipment described in any one of the above embodiments.

According to a further aspect of the disclosed embodiments, a computer readable storage medium is provided, comprising computer program instructions, wherein the computer program instructions, when executed by a processor, implement the method according to any of the embodiments described above.

According to a further aspect of the disclosed embodiments, a computer program product is provided, comprising a computer program, wherein the computer program, when executed by a processor, implements the method according to any of the above embodiments.

In an embodiment of the disclosure, each first time slot configured by the network side for PRACH retransmission includes a first PRACH transmission time slot for PRACH single transmission, and one or more groups of second PRACH transmission time slots bound to the first PRACH transmission time slot. In such a way, on one hand, the network side does not need to completely multiplex the PRACH transmission time for PRACH single transmission, thereby reducing the probability of PRACH collision; on the other hand, the network side does not need to additionally configure a whole set of PRACH transmission time for PRACH repeated transmission, thereby reducing the waste of resources. In this way, collision of PRACH and waste of resources can be balanced.

The technical scheme of the present disclosure is described in further detail below through the accompanying drawings and examples.

Drawings

In order to more clearly illustrate the embodiments of the present disclosure or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and other drawings may be obtained according to these drawings without inventive effort to a person of ordinary skill in the art.

Fig. 1 is a flow chart of a PRACH retransmission method according to some embodiments of the present disclosure;

FIG. 2 is a time-frequency position schematic diagram of a first occasion according to some embodiments of the present disclosure;

fig. 3 is a schematic association of SSB indexes and PRACH transmission occasions in a first PRACH transmission resource according to some embodiments of the present disclosure;

fig. 4 is a flow chart illustrating PRACH detection at a network side according to some embodiments of the present disclosure;

fig. 5 is a flow chart of a PRACH retransmission method according to further embodiments of the present disclosure;

fig. 6 is a schematic structural diagram of a PRACH retransmission apparatus according to some embodiments of the present disclosure;

fig. 7 is a schematic structural diagram of a PRACH retransmission apparatus according to further embodiments of the present disclosure;

fig. 8 is a schematic structural diagram of a PRACH retransmission apparatus according to some embodiments of the present disclosure;

fig. 9 is a schematic structural diagram of a PRACH retransmission system according to some embodiments of the present disclosure.

Detailed Description

The following description of the technical solutions in the embodiments of the present disclosure will be made clearly and completely with reference to the accompanying drawings in the embodiments of the present disclosure, and it is apparent that the described embodiments are only some embodiments of the present disclosure, not all embodiments. All other embodiments, which can be made by one of ordinary skill in the art based on the embodiments in this disclosure without inventive faculty, are intended to fall within the scope of this disclosure.

The relative arrangement of the components and steps, numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present disclosure unless it is specifically stated otherwise.

Meanwhile, it should be understood that the sizes of the respective parts shown in the drawings are not drawn in actual scale for convenience of description.

Techniques, methods, and apparatus known to one of ordinary skill in the relevant art may not be discussed in detail, but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any specific values should be construed as merely illustrative, and not a limitation. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further discussion thereof is necessary in subsequent figures.

The present disclosure proposes a PRACH retransmission method. Fig. 1 is a flow chart of a PRACH retransmission method according to some embodiments of the present disclosure. The PRACH repeated transmission method is applied to a network side.

In step 102, the network side configures at least one first timeslot for PRACH repeated transmission, where each first timeslot includes a first PRACH transmission occasion and one or more groups of second PRACH transmission occasions bound to the first PRACH transmission occasion, and the first PRACH transmission occasion is further used for PRACH single transmission.

Each first time machine configured by the network side and used for PRACH repeated transmission comprises a first PRACH transmission time for PRACH single transmission and one or more groups of second PRACH transmission time bound with the first PRACH transmission time. In such a way, on one hand, the network side does not need to completely multiplex the PRACH transmission time for PRACH single transmission, thereby reducing the probability of PRACH collision; on the other hand, the network side does not need to additionally configure a whole set of PRACH transmission time for PRACH repeated transmission, thereby reducing the waste of resources. In this way, collision of PRACH and waste of resources can be balanced.

Fig. 2 is a time-frequency position schematic diagram of a first occasion according to some embodiments of the present disclosure.

For example, a first PRACH transmission occasion #1-1 is bundled with two sets of second PRACH transmission occasions. One set of second PRACH transmission occasions includes PRACH transmission occasions #2-0 and PRACH transmission occasions #2-4, and the other set of second PRACH transmission occasions includes PRACH transmission occasions #2-1, #2-2, #2-3 and #2-5.

In some embodiments, the network side configures a first PRACH transmission resource for a single PRACH transmission. For example, PRACH configuration information related to the first PRACH transmission resource is indicated by a PRACH-configuration index of a system information block (System Information Block, SIB) 1, and the value of the parameter is an index value of 0-255, corresponding to a row index in the random access configuration table, specifically indicating the following information: a preamble format, a system frame number, a subframe number, a starting orthogonal frequency division multiplexing (Orthogonal Frequency Division Multiplexing, OFDM) symbol position, a number of slots within one subframe for transmitting PRACH, a number of PRACH time domain transmission occasions within one PRACH slot, and a number of persistent symbols of PRACH. For example, one system frame has a length of 10ms, each system frame includes 10 subframes, each having a length of 1ms, each subframe includes one or more slots, and each slot is composed of a plurality of consecutive OFDM symbols. The format of the preamble for a single transmission, the time domain position of PRACH transmission opportunity for a single transmission, and the number of PRACH transmission opportunities in the time domain can be determined from the above information.

In some embodiments, the number of PRACH transmission occasions of the first PRACH transmission resource in the frequency domain may be indicated by a parameter msg1-FDM, which may be configured to {1,2,4,8}, e.g., when the parameter is configured to 1, indicating that there are 1 PRACH transmission occasions in the frequency domain.

And determining the total number of PRACH transmission occasions of the first PRACH transmission resource according to the PRACH transmission occasion number of the first PRACH in the time domain and the transmission occasion number of the first PRACH in the frequency domain.

In some embodiments, the network side indicates the number of PRACH transmission occasions associated with each Synchronization Signal Block (SSB) index and the number of preambles corresponding to each SSB index by the configuration parameter SSB-perRACH-occidionandbb-preablessessb. The above-mentioned parameters are used to indicate the number of preambles used by the contention-based random access procedure.

Among the parameters SSB-perRACH-occidionandcb-preambiserssb, the parameter SSB-perRACH-occidion indicates the number of PRACH transmission occasions associated with each SSB index, whose values include { onelight, one, two, four, light, six }. For example, when the parameter SSB-perRACH-transmission takes on the value oneHalf (1/2), it indicates that 1 SSB index is associated with 2 PRACH transmission occasions; when the parameter SSB-perRACH-allocation takes on the value two (2), it indicates that 2 SSB indexes are associated with 1 PRACH transmission Occasion.

Among the parameters SSB-perRACH-occidionandbb-preablesspersb, the parameter CB-preablesspersb indicates the number of preambles corresponding to each SSB index. In some implementations, when the parameter SSB-perRACH-occidionandbs-preamps PerSSB has a value oneHalf { n4}, it means that 1 SSB index is associated with 2 PRACH transmission occasions, each SSB index corresponding to 4 contended Preambles.

According to the above description, each SSB index is associated with at least one PRACH transmission occasion, and the base station can indirectly obtain the information of the SSB index selected by the UE by detecting the PRACH transmission occasion adopted by the UE.

In some embodiments, when the network side configures N SSB indexes, the N SSB indexes are associated with corresponding PRACH transmission occasions one by one according to a certain rule, and after each of the N SSBs is associated with one PRACH transmission occasion, the N SSB indexes are considered to be associated with one round of association, if there are remaining PRACH transmission occasions, the N SSB indexes continue to be associated with the remaining PRACH transmission occasions until the remaining PRACH transmission occasions are insufficient to support one round of SSB index association mapping. In some embodiments, the last remaining PRACH transmission occasion is not PRACH transmission.

Fig. 3 is a schematic association relationship between SSB indexes and PRACH transmission opportunities in a first PRACH transmission resource according to some embodiments of the present disclosure.

As shown in fig. 3, in one PRACH period, the number of PRACH transmission occasions in the time domain is 2, the value of the parameter msg1-FDM is 4, the value of the parameter SSB-perRACH-occupancy is 1, and three SSB indexes are respectively indicated as ssb#0, ssb#1, and ssb#2. For example, the length of one PRACH period may be equal to the length of one system frame (10 ms).

The msg1-FDM parameter is 4, which indicates that the number of PRACH transmission occasions in the frequency domain is 4, and the PRACH transmission occasions in the time domain is 2, and the total number of PRACH transmission occasions is 8, which are respectively indicated by PRACH transmission occasions #0 to # 7.

The value of parameter SSB-perRACH-indication is 1, indicating that one SSB index is associated with one PRACH transmission Occasion.

The three SSB indexes are sequentially associated with transmission opportunities #0 to #7 in a manner of increasing the index number. The first round of association is as follows: ssb#0 is associated with PRACH transmission occasion #0, ssb#1 is associated with PRACH transmission occasion #1, and ssb#2 is associated with PRACH transmission occasion # 2. The second round of association is as follows: ssb#0 is associated with PRACH transmission occasion #3, ssb#1 is associated with PRACH transmission occasion #4, and ssb#2 is associated with PRACH transmission occasion # 5. When two rounds of association are completed, the remaining PRACH transmission occasions #6 and #7, which are not associated to SSB indexes, are not used for PRACH transmission because the number of remaining PRACH transmission occasions is insufficient to support a full round of SSB index association mapping.

In some embodiments, after the network side completes the configuration, the configuration information is sent to the UE through SIB1, so that the UE selects a corresponding PRACH transmission occasion according to the configuration information to implement single transmission of the preamble.

In some embodiments, the first PRACH transmission opportunity may be configured according to a method for configuring the first PRACH transmission resource, and based on the configuration of the first PRACH transmission opportunity, a binding relationship between at least one first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities is further configured to configure at least one first opportunity. By the configuration method, in order to realize PRACH repeated transmission, the network side can additionally configure the binding relationship between at least one first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities on the basis of the first PRACH transmission resources of single transmission, and other configurations are not needed. Therefore, the configuration process can be simplified, and the configuration efficiency of PRACH transmission resources can be improved. In addition, the method does not need to modify the parameters of the first PRACH transmission resource, can ensure that the UE transmitting the preamble for one time and the UE transmitting the preamble repeatedly are consistent in understanding the parameters, and improves the compatibility of configuration.

Fig. 4 is a flow diagram of PRACH detection at the network side according to some embodiments of the present disclosure.

In some embodiments, the PRACH repeat transmission method includes one or more of steps 402-408 shown in fig. 4.

In step 402, PRACH detection is performed on any one of the first occasions to obtain a first preamble that the UE repeatedly transmits.

At step 404, the RA-RNTI is determined from one of the second PRACH transmission occasions in any one of the first occasions.

In step 406, the first lower DCI is scrambled with the RA-RNTI to obtain a second DCI. The first DCI is, for example, DCI 1_0.

In step 408, the second DCI and the RAR scheduled by the second DCI are sent, where the RAR carries the RAPID of the first preamble.

In the above steps, the network side determines the RA-RNTI according to a second PRACH transmission opportunity, which can avoid the same RA-RNTI determined by the UE transmitting the preamble once, thereby avoiding resource collision between the UE transmitting the preamble once and the UE transmitting the preamble repeatedly.

In some embodiments, the RA-RNTI is calculated based on the following parameters: the first OFDM symbol index of the second PRACH transmission occasion, the first slot index of the second PRACH transmission occasion in one system frame, the index of the second PRACH transmission occasion in the frequency domain, the uplink carrier ID for random access (the value is 0 for the normal uplink carrier and 1 for the supplementary uplink carrier). The first three of the above parameters are determined by the time-frequency position of the second PRACH transmission occasion.

The inventors have noted that there is an overlap between groups of second PRACH transmission occasions that bind to the same first PRACH transmission occasion, which may result in resource collision between different UEs.

For example, as shown in fig. 2, assume that a first PRACH transmission occasion #1-1 is bundled with one set of second PRACH transmission occasions #2-0, #2-2, and #2-3, while another set of second PRACH transmission occasions #2-0 and #2-4 are bundled, the two sets of PRACH transmission occasions comprising the same second PRACH transmission occasion #2-0. If the UE1 selects PRACH transmission occasions #1-1, #2-0, #2-2 and #2-3 to repeat transmission preambles and the UE2 selects PRACH transmission occasions #1-1, #2-0 and #2-4 to repeat transmission preambles, the UE1 and the UE2 are identical to RA-RNTIs determined according to the second PRACH transmission occasion #2-0 in case of calculating the RA-RNTIs according to the second PRACH transmission occasion #2-0. If both UEs select the same preamble, since UE2 determines the same RA-RNTI as UE1, both UE1 and UE2 can descramble the DCI, which may cause resource collision of UE1 and UE 2.

In view of this, the embodiments of the present disclosure also propose the following solutions.

In some embodiments, the one or more sets of second PRACH transmission occasions bundled with the first PRACH transmission occasion include a first set of second PRACH transmission occasions and a second set of second PRACH transmission occasions other than the first set of second PRACH transmission occasions. It should be appreciated that each set of second PRACH transmission occasions other than the first set of second PRACH transmission occasions is referred to as a second set of second PRACH transmission occasions.

In this case, one second PRACH transmission occasion for calculating the RA-RNTI belongs to the first group of second PRACH transmission occasions and is different from the second group of second PRACH transmission occasions. In this way, when other UEs and UEs transmitting the first preamble select different groups of second PRACH transmission opportunities, other UEs can be ensured not to descramble DCI corresponding to the UEs transmitting the first preamble, so that the possibility of resource collision among different UEs is reduced.

For example, as shown in fig. 2, the first PRACH transmission occasion #1-1 is bundled with multiple sets of second PRACH transmission occasions, respectively (1) second PRACH transmission occasions #2-0, #2-2, and #2-3; (2) a second PRACH transmission occasion #2-0 and #2-4; and (3) a second PRACH transmission occasion #2-5.

In some cases, (1) is determined to be a first set of second PRACH transmission occasions and (2) and (3) are determined to be a second set of second PRACH transmission occasions. In this case, the RA-RNTI is calculated from one of the first set of second PRACH transmission occasions #2-3 that is different from the second set of second PRACH transmission occasions.

In some embodiments, for ease of configuration, the UE and the network side agree to determine the first second PRACH transmission occasion or the last second PRACH transmission occasion of the first set of second PRACH transmission occasions as one second PRACH transmission occasion for calculating the RA-RNTI.

In some embodiments, the first PRACH transmission occasion is different in time domain from each second PRACH transmission occasion in each first occasion. When PRACH transmission is carried out on different frequency domains of the same time domain, the frequency division reduces the transmission power of each frequency domain, which is not beneficial to the detection of the lead code by a network side, and the repeated transmission of the lead code on different time domains does not reduce the transmission power, and the probability of the lead code being detected can be improved, so that the configuration of the first PRACH transmission opportunity and each second PRACH transmission opportunity is different on the time domain, which is beneficial to the improvement of the probability of the successful PRACH transmission, thereby improving the coverage performance of the PRACH.

In some embodiments, the network side configures at least one of the one or more sets of second PRACH transmission occasions to include a plurality of second PRACH transmission occasions that do not overlap each other in the time domain. Thus, the success rate of the repeated transmission of the preamble on a plurality of PRACH transmission occasions with different time domains can be further improved.

In some embodiments, the network side is further configured with second occasions for single transmission of the PRACH, each second occasion comprising a first PRACH transmission occasion, the second set of preambles associated with the second occasion being different from the first set of preambles associated with the first occasion of repeated transmission of the preamble. In other words, the second set of preambles and the first set of preambles do not include the same preamble. In this way, the network side can distinguish whether the UE repeatedly transmits the preamble or the single transmission preamble according to the preamble, so as to avoid resource conflict between the UE performing the single transmission preamble and the UE performing the repeated transmission preamble caused by adopting the same preamble.

For example, when the first PRACH transmission occasion is further used for a single PRACH transmission, the UE1 transmits the preamble 1 on the first PRACH transmission occasion, and the first PRACH transmission occasion is formed by bundling a set of second PRACH transmission occasions, where the first PRACH transmission occasion and the set of second PRACH transmission occasions form a first occasion. Another UE2 has transmitted a preamble 2 on the first occasion. The single transmission preamble and the repetition transmission preamble are associated with different preambles, i.e. preamble 1 and preamble 2 are different.

The network side detects on the first occasion, and since both UE1 and UE2 transmit the preamble on the first PRACH transmission occasion, the network side can detect the preamble 1 and the preamble 2 on the first occasion. Since preamble 1 belongs to the second set of preambles associated with the second occasion and preamble 2 belongs to the first set of preambles associated with the first occasion, the network side may determine that preamble 2 is a UE from one repeated transmission preamble. For the preamble 1, the RA-RNTI may be determined according to the time-frequency location of the first PRACH transmission occasion according to the processing method of the single transmission. And for UE2 that repeatedly transmits preamble 2, the network side may determine the RA-RNTI from the time-frequency location of one of the set of second PRACH transmission occasions. Therefore, the network side can distinguish the UE1 for transmitting the preamble from the UE2 for repeatedly transmitting the preamble through the preamble, so that the network side can conveniently allocate transmission resources for transmitting the subsequent random access process for different UEs, and resource conflict is avoided.

In some embodiments, the network side configures an association relationship between each first occasion and SSB indexes, and in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions are associated with the same one or more SSB indexes. That is, one or more sets of second PRACH transmission occasions bound to the first PRACH transmission occasion multiplex the association of the first PRACH transmission occasion with the SSB index. Therefore, the network side does not need to configure the association relation between the SSB index and each second PRACH transmission opportunity, and the configuration process of the network side is simplified.

For example, after selecting the SSB index corresponding to the beam with the best transmission quality, the UE repeatedly transmits the preamble at one first occasion associated with the SSB index. When the network side detects the PRACH, the association relation between the SSB index and the first time machine can be used for determining the SSB index selected by the UE, further determining the beam with the best transmission quality selected by the UE, and transmitting information required by the subsequent random access process in the beam direction so as to be convenient for the UE to receive.

In some embodiments, the network side also sends radio resource control information to inform the UE whether the network side turns on PRACH retransmission. When the network side configures the first time machine and sends the radio resource control information to inform the UE to start PRACH (physical random access channel) retransmission, the UE can select one first time machine to realize the retransmission of the preamble according to the configuration information. Therefore, the network side is convenient to control the PRACH repeated transmission to be started or closed, the network side is convenient to uniformly control PRACH transmission resources, and the UE can be ensured to know whether the network side starts the PRACH repeated transmission or not in time. The above-described manner of informing the UE whether to turn on PRACH retransmission may also be referred to as explicit indication manner.

In some implementations, the network side directly indicates that PRACH retransmission is started or not started through a predetermined field in the radio resource control information, if the field is 0, the PRACH retransmission is indicated not to be started; when the value of this field is 1, this indicates that PRACH retransmission is turned on.

In other embodiments, when the network side configures the first time slot and transmits configuration information including the first time slot to the UE, the UE starts the PRACH retransmission function by default and performs retransmission on one first time slot. Therefore, the network side does not need to inform the UE, and the UE can realize repeated transmission of the preamble as long as the UE knows the first time from the configuration information, so that the time and resources for the network side to send the radio resource control information are saved. The above-mentioned manner of informing the UE whether to turn on PRACH retransmission may also be referred to as an implicit indication manner.

In some embodiments, the network side further transmits configuration information of the PRACH, the configuration information including first indication information indicating at least one first time period for PRACH retransmission, each first time period including a first PRACH transmission opportunity and one or more sets of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, the first PRACH transmission opportunity further being for PRACH single transmission. The network side informs the UE of the configuration condition of PRACH transmission resources by sending configuration information, so that the UE can select a first time machine to realize the repeated transmission of the preamble.

In some embodiments, any of the above-mentioned configuration situations of the PRACH transmission resources by the network side may be carried in the configuration information.

Fig. 5 is a flow chart of a PRACH retransmission method according to further embodiments of the present disclosure. The PRACH repeated transmission method is applied to the UE. In some embodiments, the PRACH repeat transmission method comprises one or more of steps 502-506.

In step 502, the UE receives configuration information of a PRACH, where the configuration information includes first indication information, the first indication information indicates at least one first time period for PRACH retransmission, each first time period includes a first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, and the first PRACH transmission opportunity is further used for PRACH single transmission.

In step 504, the UE determines a first occasion from the at least one first occasion.

In step 506, the UE repeatedly transmits the first preamble on a first occasion.

In some embodiments, the UE performs step 504 if a first condition is met, the first condition comprising: and knowing that the network side starts PRACH repeated transmission. In other words, the UE performs steps 504 and 506 after knowing that the network side has turned on PRACH retransmission, so that the UE can relieve the pressure and avoid unnecessary operations.

In some implementations, if the network side has configured the first occasion, and sends the configuration of the first occasion to the UE through the configuration information, the UE may determine, in the received configuration information, that the network side has turned on PRACH retransmission, and then may select a first occasion to perform retransmission of the preamble.

In other implementations, the UE knows whether the network side starts PRACH retransmission by receiving radio resource control information sent by the network side. For example, when the UE receives the radio resource control information with bit value of 1 sent by the network side, the UE knows that the network side starts PRACH retransmission.

In some embodiments, step 404 comprises: determining the PRACH repeated transmission times; and determining a first time according to the PRACH repeated transmission times. Determining the corresponding first opportunity by the UE according to the number of PRACH retransmissions may reduce the waste of PRACH transmission resources.

In some implementations, the UE determines the number of PRACH retransmissions based on at least one of a received power of the received downlink signal and a path loss of the downlink.

The manner in which the number of PRACH retransmissions is determined is described below in connection with various embodiments.

In some embodiments, the UE determines the number of PRACH retransmissions based on the received power of the received downlink signal. For example, the UE obtains the received power of the downlink signal by measuring the downlink signal.

As some implementations, the larger the received power, the smaller the number of PRACH retransmissions. In this way, when the signal is relatively weak, the UE may repeatedly transmit the preamble multiple times to increase the probability that the preamble is received by the network side; and when the signal is relatively strong, the UE can reduce the times of repeated transmission of the preamble, so that the resource waste is avoided.

For example, the UE presets a power level and a power range of each power level, and when the received power of the downlink signal measured by the UE is smaller than a first threshold, determines that the number of PRACH repeated transmissions is a first value; when the received power is larger than or equal to the first threshold and smaller than the second threshold, determining that the PRACH repeated transmission times is a second value smaller than the first value; and when the received power is larger than the second threshold, determining the PRACH repeated transmission times to be a third value smaller than the second value.

For another example, the UE determines the number of PRACH retransmissions based on a difference between the received power and a third threshold. The PRACH repeat transmission times corresponding to the third threshold is preset to a fifth value. The fifth value is the maximum PRACH retransmission number. When the difference between the received power measured by the UE and the third threshold is smaller than the fourth value, the received power is closer to or smaller than the third threshold, and at this time, the PRACH repeated transmission number of the UE is determined to be a fifth value. And when the difference is greater than or equal to the fourth value and smaller than the sixth value, the difference between the received power and the third threshold is increased, and the PRACH repeated transmission number is determined to be a seventh value smaller than the fifth value. When the difference is further increased to be greater than or equal to the sixth value, indicating that the received power is much greater than the third threshold, determining that the number of PRACH retransmissions is an eighth value that is less than the seventh value. According to the mode, the corresponding relation between the PRACH repeated transmission times and the received power is set until the received power is increased until the preamble is not required to be repeatedly transmitted.

In other embodiments, the number of PRACH retransmissions is determined based on the path loss. For example, the UE obtains the downlink path loss by measuring the downlink signal and calculating.

As some implementations, the smaller the path loss, the smaller the number of PRACH retransmissions. Conversely, when the loss is larger, the determined number of repeated transmissions is larger. In such a way, when the path loss is large, the UE can repeatedly transmit the preamble for a plurality of times to improve the probability that the preamble is received by the network side; and when the path loss is small, the UE does not need to transmit the preamble for many times, and the UE has extremely high probability of being detected by the network side, so that the UE can reduce the times of repeatedly transmitting the preamble and avoid resource waste.

For example, when the path loss is smaller than the fourth threshold, determining that the number of PRACH repeated transmissions is a sixth value; when the path loss is greater than or equal to the fourth threshold and smaller than the fifth threshold, determining that the PRACH repeated transmission times is a seventh value larger than the sixth value; and when the received power is greater than the fifth threshold, determining that the PRACH repeated transmission number is an eighth value greater than the seventh value.

For another example, the UE determines the number of PRACH retransmissions based on a difference between the path loss and a sixth threshold. The number of PRACH retransmissions corresponding to the sixth threshold is preset to a tenth value. And when the difference value between the path loss and the sixth threshold is smaller than the ninth value, the path loss and the sixth threshold are closer to or smaller than the sixth threshold, and the PRACH repeated transmission number of the UE is determined to be the tenth value. And when the difference between the path loss and the sixth threshold increases to be greater than or equal to the ninth value and smaller than the eleventh value, determining that the number of PRACH retransmissions is a twelfth value greater than the tenth value. When the difference is further increased to be greater than or equal to the eleventh value, the PRACH retransmission number is determined to be a thirteenth value greater than the twelfth value. And setting the corresponding relation between the PRACH repeated transmission times and the path loss according to the mode until the PRACH repeated transmission times reach the maximum value supported by PRACH repeated transmission resources.

In some embodiments, the total number of PRACH transmission occasions in one first occasion selected by the UE for PRACH retransmission is the same as the number of PRACH retransmissions. In this case, the first preamble is repeatedly transmitted on the first PRACH transmission occasion and the second PRACH transmission occasion among the first occasions.

The method can not occupy excessive PRACH transmission resources under the condition of improving the probability that the preamble sent by the UE is detected by the network side.

In some implementations, in a case that the total number of PRACH transmission occasions in one first occasion selected by the UE for PRACH retransmission is the same as the number of PRACH retransmission times, the configuration information further includes third indication information, where the third indication information is used to indicate an association relationship between each first occasion and SSB indexes, and in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions are associated with the same one or more SSB indexes.

In these implementations, the UE may determine the first occasion for PRACH retransmission by the following method.

Determining a first transmission PRACH transmission occasion associated with the SSB index selected by the UE as a candidate first PRACH transmission occasion;

determining as one first occasion one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a second condition, wherein the second condition comprises: the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is equal to the number of PRACH retransmissions minus one.

Because the association relation between the SSB index and each first occasion is determined, the network side determines the SSB index selected by the UE through the time-frequency position of the first occasion of receiving the preamble, and sends information required by the subsequent random access process in the beam direction corresponding to the SSB index so as to improve the probability of receiving the information by the UE.

For example, the UE determines that the number of repeated transmissions is 3, and the association relationship between the ssb index and the first PRACH transmission opportunity is shown in fig. 2. The SSB index selected by the UE at the time of cell search is ssb#0, and the ssb#0 is associated with the first PRACH transmission occasions #0, #2, #4, #6 according to the association relationship shown in fig. 2. Each first PRACH transmission occasion is also bundled with one or more sets of second PRACH transmission occasions, wherein the first PRACH transmission occasion #2 is bundled with the second PRACH transmission occasions #2-0 and #2-5 shown in fig. 3. The UE selects one first PRACH transmission occasion #2 among candidate first PRACH transmission occasions #0, #2, #4, #6 associated with SSB # 0. And in a group of second PRACH transmission occasions bound with the first PRACH transmission occasion, the number of the second PRACH transmission occasions is 2, which is equal to the number of PRACH repeated transmission times minus one. The PRACH transmission occasions #2, #2-0, and #2-5 are determined as first occasions at which the UE repeatedly transmits the preamble, and the first preamble is repeatedly transmitted on the first PRACH transmission occasion #2 and the second PRACH transmission occasions #2-0 and #2-5 among the first occasions.

In other embodiments, the number of second PRACH transmission occasions in one first occasion selected by the UE for PRACH retransmission is the same as the number of PRACH retransmissions. In this case, the first preamble is repeatedly transmitted on a second PRACH transmission occasion among the first occasions.

When the UE performs PRACH repeated transmission, the preamble is transmitted on the second PRACH transmission time, so that the network side can conveniently distinguish the UE performing PRACH single transmission and PRACH repeated transmission, and the probability of resource conflict between the UE performing PRACH single transmission and PRACH repeated transmission is further reduced.

In the case that the number of second PRACH transmission occasions in one first occasion selected by the UE for PRACH retransmission is the same as the number of PRACH retransmission times, the configuration information further includes third indication information, where the third indication information is used to indicate an association relationship between each first occasion and SSB indexes, and in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions are associated with the same one or more SSB indexes.

Determining one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a third condition as one first occasion, wherein the third condition includes: the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is the same as the number of PRACH repeat transmissions.

For example, the UE determines that the number of repeated transmissions is 3, and the association relationship between the ssb index and the first PRACH transmission opportunity is shown in fig. 2. The SSB index selected by the UE at the time of cell search is ssb#0, and the ssb#0 is associated with the first PRACH transmission occasions #0, #2, #4, #6 according to the association relationship shown in fig. 2. Each first PRACH transmission occasion is also bundled with one or more sets of second PRACH transmission occasions, wherein the first PRACH transmission occasion #3 is bundled with the second PRACH transmission occasions #2-1, #2-3 and #2-4 shown in fig. 3. The UE selects one first PRACH transmission occasion #3 among candidate first PRACH transmission occasions #0, #2, #4, #6 associated with SSB # 0. The number of the second PRACH transmission occasions of the group bound by the first PRACH transmission occasion #3 is 3, which is equal to the number of PRACH repeated transmissions. The PRACH transmission occasions #3, #2-1, #2-3, and #2-4 are determined as first occasions at which the UE repeatedly transmits the preamble, and the first preamble is repeatedly transmitted on second PRACH transmission occasions #2-1, #2-3, and #2-4 among the first occasions. In some embodiments, the method for the UE to repeatedly transmit the PRACH after repeatedly transmitting the preamble further includes the steps of: receiving a second DCI; determining an RA-RNTI according to a second PRACH transmission time in a first time of the repeated transmission preamble selected by the UE; descrambling the second DCI by utilizing the RA-RNTI to obtain first DCI; and receiving RAR according to the first DCI.

After the UE sends the preamble, it needs to monitor the PDCCH in the RAR time window, where the PDCCH is used to carry the second DCI sent by the network side, and the UE monitors the PDCCH to receive the second DCI, where the second DCI is obtained by scrambling the first DCI with the RA-RNTI by the network side. In order for the UE to successfully receive the RAR sent by the network side for the UE, the RA-RNTI value determined by the UE must be the same as that of the network side, so when the UE selects a first occasion, a second PRACH transmission occasion is selected from the first occasion according to a pre-agreement with the network side to determine the RA-RNTI.

In some embodiments, in order to reduce the probability that other UEs are identical to the RA-RNTI determined by the UE transmitting the first preamble on the basis of ensuring that the RA-RNTI value determined by the UE is identical to the network side, one or more groups of second PRACH transmission occasions bound to the first PRACH transmission occasion are divided into two groups, including a first group of second PRACH transmission occasions and a second group of second PRACH transmission occasions other than the first group of second PRACH transmission occasions. A second PRACH transmission of the first set of second PRACH transmission occasions that is different from each of the second set of second PRACH transmission occasions is determined as one second PRACH transmission occasion for calculating the RA-RNTI.

In some embodiments, when the RAR received by the UE carries the RAID of the first preamble sent by the UE, the PRACH transmission is proved to be successful, and the UE executes the subsequent random access procedure. In some embodiments, the RAR includes information required for the UE to perform the subsequent random access procedure.

For other embodiments of the PRACH retransmission method applied to the UE, please refer to the embodiments of the PRACH retransmission method applied to the network side, and the description thereof is omitted herein.

In this specification, each embodiment is described in a progressive manner, and each embodiment is mainly described in a different manner from other embodiments, so that the same or similar parts between the embodiments are mutually referred to. For the device embodiments, since they basically correspond to the method embodiments, the description is relatively simple, and the relevant points are referred to in the description of the method embodiments.

Fig. 6 is a schematic structural diagram of a PRACH retransmission apparatus according to some embodiments of the present disclosure, which is applied to a network side.

As shown in fig. 6, the PRACH retransmission apparatus includes a configuration module 601. The configuration module 601 is configured to configure at least one first time slot for PRACH repeated transmission, each first time slot comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bundled with the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

It should be understood that the PRACH retransmission apparatus described above may further include other modules to execute the PRACH retransmission method applied to the network side in any of the embodiments described above.

Fig. 7 is a schematic structural diagram of a PRACH retransmission apparatus according to still further embodiments of the present disclosure.

As shown in fig. 7, the PRACH retransmission apparatus includes a receiving module 701, a determining module 703, and a transmitting module 705.

The receiving module 701 is configured to receive configuration information of a PRACH, where the configuration information includes first indication information indicating at least one first time period for PRACH retransmission, each first time period including a first PRACH transmission opportunity and one or more sets of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, the first PRACH transmission opportunity also being used for PRACH single transmission.

The determining module 703 is configured to determine a first occasion.

The transmission module 705 is configured to repeat transmission of the preamble on a first occasion.

It should be understood that the PRACH retransmission apparatus described above may further include other modules to perform the PRACH retransmission method applied to the UE of any of the above embodiments.

For other embodiments of the PRACH retransmission apparatus, please refer to the embodiments of the PRACH retransmission method described above, and the description thereof is omitted herein.

Fig. 8 is a schematic structural diagram of a PRACH retransmission apparatus according to some embodiments of the present disclosure.

As shown in fig. 8, the PRACH retransmission apparatus 800 includes a memory 801 and a processor 802 coupled to the memory 801, the processor 802 being configured to perform the method of any of the foregoing embodiments applied to a network side or UE based on instructions stored in the memory 801.

The memory 801 may include, for example, system memory, fixed nonvolatile storage media, and the like. The system memory may store, for example, an operating system, application programs, boot Loader (Boot Loader), and other programs.

The PRACH retransmission apparatus 800 may further include an input-output interface 803, a network interface 804, a storage interface 805, and the like. These interfaces 803, 804, 805 and the memory 801 and the processor 802 may be connected via a bus 806, for example. The input output interface 603 provides a connection interface for input output devices such as a display, mouse, keyboard, touch screen, etc.

In some embodiments, the disclosure further proposes a base station, which includes the PRACH retransmission apparatus of any one of the embodiments above, for example, the PRACH retransmission apparatus shown in fig. 6 or fig. 8.

In some embodiments, the disclosure further proposes a UE including the PRACH retransmission apparatus of any one of the embodiments described above, for example, the PRACH retransmission apparatus shown in fig. 7 or fig. 8.

Fig. 9 is a schematic structural diagram of a PRACH retransmission system including a base station 901 and a UE902 according to some embodiments of the present disclosure.

The disclosed embodiments also provide a computer readable storage medium comprising computer program instructions which, when executed by a processor, implement the method of any of the above embodiments.

The disclosed embodiments also provide a computer program product comprising a computer program which, when executed by a processor, implements the method of any of the above embodiments.

Thus, various embodiments of the present disclosure have been described in detail. In order to avoid obscuring the concepts of the present disclosure, some details known in the art are not described. How to implement the solutions disclosed herein will be fully apparent to those skilled in the art from the above description.

It will be appreciated by those skilled in the art that embodiments of the present disclosure may be provided as a method, system, or computer program product. Accordingly, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present disclosure may take the form of a computer program product embodied on one or more computer-usable non-transitory storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present disclosure is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that functions specified in one or more of the flowcharts and/or one or more of the blocks in the block diagrams may be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present disclosure. It will be understood by those skilled in the art that the foregoing embodiments may be modified and equivalents substituted for elements thereof without departing from the scope and spirit of the disclosure. The scope of the present disclosure is defined by the appended claims.

Claims

1. A PRACH repeated transmission method is applied to a network side and comprises the following steps:

at least one first time machine configured for PRACH repeat transmission, each first time machine comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bundled with the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

2. The method of claim 1, further comprising:

PRACH detection is carried out on any first occasion to obtain a first preamble which is repeatedly transmitted by User Equipment (UE);

determining a random access radio network temporary identifier RA-RNTI according to a second PRACH transmission occasion in the random first occasion;

scrambling the first downlink control information DCI by utilizing the RA-RNTI to obtain a second DCI;

and sending the second DCI and a random access response RAR scheduled by the second DCI, wherein the RAR carries a random access preamble identifier RAPID of the first preamble.

3. The method of claim 1, wherein the one or more sets of second PRACH transmission occasions comprise a first set of second PRACH transmission occasions and a second set of second PRACH transmission occasions other than the first set of second PRACH transmission occasions, the one second PRACH transmission occasion belonging to the first set of second PRACH transmission occasions, the one second PRACH transmission occasion being different from the second set of second PRACH transmission occasions.

4. The method of claim 3, wherein the one second PRACH transmission occasion is a first second PRACH transmission occasion or a last second PRACH transmission occasion of the first set of second PRACH transmission occasions.

5. The method of any of claims 1-4, wherein, in each first occasion, the first PRACH transmission occasion is different from each second PRACH transmission occasion in the time domain.

6. The method of any of claims 1-5, wherein at least one of the one or more sets of second PRACH transmission occasions comprises a plurality of second PRACH transmission occasions that do not overlap each other in the time domain.

7. The method of any of claims 1-6, further comprising:

at least one second occasion configured for a single transmission of the PRACH, each second occasion comprising a first PRACH transmission occasion, the second set of preambles associated with the second occasion being different from the first set of preambles associated with each first occasion.

8. The method of any of claims 1-7, further comprising:

and configuring the association relation between each first occasion and the SSB index of the synchronous signal block, wherein in each first occasion, the first PRACH transmission occasion and each group of second PRACH transmission occasions are associated with the same one or more SSB indexes.

9. The method of any of claims 1-8, further comprising:

and sending the radio resource control information to inform the UE whether the network side starts PRACH repeated transmission.

10. The PRACH repeated transmission method is applied to a network side and comprises the following steps:

and sending configuration information of the PRACH, wherein the configuration information comprises first indication information, the first indication information indicates at least one first time machine used for PRACH repeated transmission, each first time machine comprises a first PRACH transmission time and one or more groups of second PRACH transmission time bound with the first PRACH transmission time, and the first PRACH transmission time is also used for PRACH single transmission.

11. A method of PRACH retransmission, applied to a UE, comprising:

receiving configuration information of PRACH, wherein the configuration information comprises first indication information, the first indication information indicates at least one first time machine used for PRACH repeated transmission, each first time machine comprises a first PRACH transmission time and one or more groups of second PRACH transmission time bound with the first PRACH transmission time, and the first PRACH transmission time is also used for PRACH single transmission;

determining a first occasion from the at least one first occasion;

and repeating the transmission of the first preamble on the first occasion.

12. The method of claim 11, wherein the determining a first timing from the at least one first timing comprises:

Determining a first occasion from the at least one first occasion when a first condition is satisfied, the first condition including: and knowing that the network side starts PRACH repeated transmission.

13. The method of claim 11 or 12, wherein said determining a first time from said at least one first time comprises:

determining the PRACH repeated transmission times;

and determining the first opportunity according to the PRACH repeated transmission times.

14. The method of claim 13, wherein the determining the number of PRACH retransmissions comprises:

and determining the PRACH repeated transmission times according to at least one of the received power of the received downlink signal and the path loss of the downlink.

15. The method of claim 14, wherein the larger the received power is, the smaller the number of PRACH retransmissions.

16. The method of claim 14, wherein the smaller the path loss is, the smaller the number of PRACH retransmissions is.

17. The method of claim 13, wherein the total number of PRACH transmission occasions in the one first occasion is the same as the number of PRACH retransmissions, the retransmitting the first preamble on the one first occasion comprising:

And repeatedly transmitting the first preamble on a first PRACH transmission occasion and a second PRACH transmission occasion in the first occasion.

18. The method of claim 17, wherein the configuration information further comprises third indication information indicating an association of each first occasion with an SSB index, in each first occasion, the first PRACH transmission occasion and each set of second PRACH transmission occasions associated with the same one or more SSB indices;

said determining a first time instant from said at least one first time instant comprises:

determining one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a second condition as the one first occasion, wherein the second condition includes:

the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is equal to the number of PRACH retransmissions minus one.

19. The method of claim 13, wherein the number of second PRACH transmission occasions in the one first occasion is the same as the number of PRACH retransmissions, the retransmitting the first preamble on the one first occasion comprising:

The first preamble is repeatedly transmitted on a second PRACH transmission occasion of the one first occasion.

20. The method of claim 19, wherein the configuration information further comprises third indication information indicating an association of each first occasion with an SSB index, in each first occasion, the first PRACH transmission occasion and each set of second PRACH transmission occasions associated with the same one or more SSB indices;

determining one candidate first PRACH transmission occasion and a set of second PRACH transmission occasions bundled with the one candidate first occasion that satisfy a third condition as the one first occasion, wherein the third condition includes:

the number of second PRACH transmission occasions in the set of second PRACH transmission occasions is the same as the number of PRACH repeated transmissions.

21. The method of any of claims 11-20, wherein, in each first occasion, the first PRACH transmission occasion is different from each second PRACH transmission occasion in the time domain.

22. The method of any of claims 11-21, wherein at least one of the one or more sets of second PRACH transmission occasions comprises a plurality of second PRACH transmission occasions that do not overlap each other in the time domain.

23. The method of any of claims 11-22, the configuration information further comprising fourth indication information indicating second occasions for a single transmission of PRACH, each second occasion comprising a first PRACH transmission occasion, the second set of preambles associated with the second occasion being different from the first set of preambles associated with each first occasion.

24. The method of any of claims 11-23, further comprising:

receiving a second DCI;

determining an RA-RNTI according to a second PRACH transmission occasion in the first occasions;

descrambling the second DCI by utilizing the RA-RNTI to obtain first DCI;

and receiving RAR according to the first DCI.

25. The method of claim 24, wherein the one or more sets of second PRACH transmission occasions comprise a first set of second PRACH transmission occasions and a second set of second PRACH transmission occasions other than the first set of second PRACH transmission occasions, the one second PRACH transmission occasion belonging to the first set of second PRACH transmission occasions, the one second PRACH transmission occasion being different from the second set of second PRACH transmission occasions.

26. The method of claim 25, wherein the one second PRACH transmission occasion is a first second PRACH transmission occasion or a last second PRACH transmission occasion of the first set of second PRACH transmission occasions.

27. The method of any of claims 24-26, further comprising:

and executing a subsequent random access procedure under the condition that the RAR carries the RAID of the first preamble.

28. A PRACH retransmission apparatus, applied to a network side, comprising:

a configuration module configured to configure at least one first time machine for PRACH repeat transmission, each first time machine comprising a first PRACH transmission occasion and one or more sets of second PRACH transmission occasions bound to the first PRACH transmission occasion, the first PRACH transmission occasion also being for PRACH single transmission.

29. A PRACH retransmission apparatus, applied to a network side, comprising:

a memory; and

a processor coupled to the memory and configured to perform the method of any of claims 1-10 based on instructions stored in the memory.

30. A PRACH retransmission apparatus, applied to a UE, comprising:

a receiving module configured to receive configuration information of a PRACH, wherein the configuration information includes first indication information indicating at least one first time machine for PRACH retransmission, each first time machine including a first PRACH transmission opportunity and one or more groups of second PRACH transmission opportunities bound to the first PRACH transmission opportunity, the first PRACH transmission opportunity further being for PRACH single transmission;

A determining module configured to determine a first occasion;

and a transmission module configured to repeat transmission of the preamble on the one first occasion.

31. A PRACH retransmission apparatus, applied to a UE, comprising:

a memory; and

a processor coupled to the memory and configured to perform the method of any of claims 11-27 based on instructions stored in the memory.

32. A base station, comprising:

the apparatus of claim 28 or claim 29.

33. A user equipment, comprising:

the device of claim 30 or claim 31.

34. A PRACH retransmission system comprising:

a base station according to claim 32 and a user equipment according to claim 33.

35. A computer readable storage medium comprising computer program instructions, wherein the computer program instructions, when executed by a processor, implement the method of any of claims 1-10 or 11-27.

36. A computer program product comprising a computer program, wherein the computer program when executed by a processor implements the method of any of claims 1-10 or 11-27.