Method and apparatus for performing random access

Abstract

The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates beyond a 4G communication system such as long term evolution (LTE). In embodiments of the present disclosure, there is provided a method including transmitting a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set and during an activation period of the PRACH resource set, initiating a random access procedure, based on the PRACH resource set activated based on the first signal, wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.

Description

METHOD AND APPARATUS FOR PERFORMING RANDOM ACCESS

[0001] The present disclosure relates to the technical field of wireless communication, and in particular to a random access method, a user equipment and a base station.

[0002] Considering the development of wireless communication from generation to generation, the technologies have been developed mainly for services targeting humans, such as voice calls, multimedia services, and data services. With the commercialization of 5th-generation (5G) communication systems, it is expected that the number of connected devices will exponentially grow. Increasingly, these will be connected to communication networks. Examples of internet-of-things may include vehicles, robots, drones, home appliances, displays, smart sensors connected to various infrastructures, construction machines, and factory equipment. Mobile devices are expected to evolve in various form-factors, such as augmented reality glasses, virtual reality headsets, and hologram devices. In order to provide various services by connecting hundreds of billions of devices and things in the 6th-generation (6G) era, there have been ongoing efforts to develop improved 6G communication systems. For these reasons, 6G communication systems are referred to as beyond-5G systems.

[0003] 6G communication systems, which are expected to be commercialized around 2030, will have a peak data rate of tera (1,000 giga)-level bps and a radio latency less than 100 MSec, and thus will be 50 times as fast as 5G communication systems and have the 1 / 10 radio latency thereof.

[0004] In order to accomplish such a high data rate and an ultra-low latency, it has been considered to implement 6G communication systems in a terahertz band (for example, 95 GHz to 3 THz bands). It is expected that, due to severer path loss and atmospheric absorption in the terahertz bands than those in millimeter wave (mmWave) bands introduced in 5G, technologies capable of securing the signal transmission distance (that is, coverage) will become more crucial. As major technologies for securing the coverage, it is necessary to develop radio frequency (RF) elements, antennas, novel waveforms having a better coverage than orthogonal frequency division multiplexing (OFDM), beamforming and massive multiple input multiple output (MIMO), full dimensional MIMO (FD-MIMO), array antennas, and multiantenna transmission technologies such as large-scale antennas. In addition, there has been ongoing discussion on new technologies for improving the coverage of terahertz-band signals, such as metamaterial-based lenses and antennas, orbital angular momentum (OAM), and reconfigurable intelligence surface (RIS).

[0005] Moreover, in order to improve the spectral efficiency and the overall network performances, the following technologies have been developed for 6G communication systems: a full-duplex technology for enabling an uplink transmission and a downlink transmission to use the same frequency resource simultaneously; a network technology for utilizing satellites, high-altitude platform stations (HAPS), and the like in an integrated manner; an improved network structure for supporting mobile base stations and the like and making network operation optimization and automation and the like possible; a dynamic spectrum sharing technology via collision avoidance based on a prediction of spectrum usage; an use of artificial intelligence (AI) in wireless communication for improvement of overall network operation by utilizing AI from a designing phase for developing 6G and internalizing end-to-end AI support functions; and a next-generation distributed computing technology for overcoming the limit of user equipment (UE) computing ability through reachable super-high-performance communication and computing resources (such as mobile edge computing (MEC), clouds, and the like) over the network. In addition, by designing new protocols to be used in 6G communication systems, developing mechanisms for implementing a hardware-based security environment and safe use of data, and developing technologies for maintaining privacy, attempts to strengthen the connectivity between devices, optimize the network, promote softwarization of network entities, and increase the openness of wireless communications are continuing.

[0006] It is expected that research and development of 6G communication systems in hyper-connectivity, including person to machine (P2M) as well as machine to machine (M2M), will allow the next hyper-connected experience. Particularly, it is expected that services such as truly immersive extended reality (XR), high-fidelity mobile hologram, and digital replica could be provided through 6G communication systems. In addition, services such as remote surgery for security and reliability enhancement, industrial automation, and emergency response will be provided through the 6G communication system such that the technologies could be applied in various fields such as industry, medical care, automobiles, and home appliances.

[0007] In 6G wireless communication system, one important feature is supporting communications among massive UEs, which will cause a huge challenge for the random access. In order to deal with that massive UEs access the network, the network is required to reserve a great amount of resources for random access, e.g., the physical random access channel (PRACH) resources, and how to utilize these PRACH resources efficiently is a technical problem to be solved.

[0008] The present disclosure relates to a 5G communication system or a 6G communication system for supporting higher data rates beyond a 4G communication system such as long term evolution (LTE). In embodiments of the present disclosure, there is provided a method including transmitting a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set and during an activation period of the PRACH resource set, initiating a random access procedure, based on the PRACH resource set activated based on the first signal, wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.

[0009] In order to explain the technical solutions in the embodiments of the present disclosure more clearly, the drawings used in the description of the embodiments of the present disclosure will be briefly illustrated below.

[0010] FIG. 1 is a schematic diagram of a wireless network according to an embodiment of the present disclosure;

[0011] FIG. 2 is a schematic diagram of a base station according to an embodiment of the present disclosure;

[0012] FIG. 3 is a schematic diagram of a user equipment according to an embodiment of the present disclosure;

[0013] FIG. 4 is a schematic flowchart of a method performed by the UE in a communication system according to an embodiment of the present disclosure;

[0014] Fig. 5 is a schematic diagram where a first signal and a second signal have a one-to-one correspondence relationship according to an embodiment of the present disclosure;

[0015] Fig. 6 is a schematic diagram where a first signal and a second signal have a multiple-to-one correspondence relationship according to an embodiment of the present disclosure;

[0016] FIG. 7 is a schematic flowchart of an another method performed by the UE in a communication system according to an embodiment of the present disclosure; and

[0017] FIG. 8 is a schematic structure diagram of an electronic device according to an embodiment of the present disclosure.

[0018] An objective of the embodiments of the present disclosure is intended to solve the problem of how to improve the utilization efficiency of the PRACH resources.

[0019] In accordance with one aspect of the embodiments of the present disclosure, a method performed by a UE in a communication system is provided, including operations of:

[0020] transmitting a first signal including information related to requesting and / or assisting to activate a physical random access channel (PRACH) resource set; and

[0021] during an activation period of the PRACH resource set, initiating a random access procedure, based on the PRACH resource set activated based on the first signal;

[0022] wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.

[0023] Optionally, initiating the random access procedure includes:

[0024] receiving a second signal, wherein the second signal is used for confirming that the PRACH resource set is activated, or the second signal includes information indicating that the PRACH resource set is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated; and

[0025] initiating the random access procedure based on the activated PRACH resource set.

[0026] Optionally, the method further includes:

[0027] prior to transmitting the first signal, receiving configuration information related to a first PRACH resource set and a second PRACH resource set, wherein the second PRACH resource set is activated based on the first signal, and / or is activated based on indication of the second signal; and

[0028] wherein the first PRACH resource set includes one or more PRACH resource sets, and the second PRACH resource set includes one or more PRACH resource sets.

[0029] Optionally, the first PRACH resource set is associated with a synchronization signal block (SSB) based on a first parameter;

[0030] the second PRACH resource set is associated with a SSB based on a second parameter; and

[0031] wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is a number of SSBs mapped to each RO and / or a number of contention-based PRACH preambles mapped to each SSB.

[0032] Optionally, in case that the second PRACH resource set is not activated, the first PRACH resource set is associated with a SSB based on a third parameter;

[0033] in case that the second PRACH resource set is activated, an union of the first PRACH resource set and the second PRACH resource set is associated with the SSB based on the third parameter; and

[0034] wherein the third parameter is a number of SSBs mapped to each random access occasion (RO), and / or a number of the contention-based PRACH preambles being mapped to each SSB.

[0035] Optionally, the first PRACH resource set is configured by a first radio resource control information unit; and

[0036] the second PRACH resource set is configured by a second radio resource control information unit;

[0037] wherein the first radio resource control information unit and the second radio resource control information unit are configured by the system information; or

[0038] the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by UE specific radio resource control (RRC) signal.

[0039] Optionally, the first PRACH resource set and the second PRACH resource set are obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit.

[0040] Optionally, the configuration information for the first PRACH resource set and the second PRACH resource set includes at least one of the following:

[0041] the first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning;

[0042] the first PRACH resource set corresponds to PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to PRACH resources on a second uplink carrier;

[0043] the first PRACH resource set corresponds to PRACH resources on a first initial uplink bandwidth part (BWP), and the second PRACH resource set corresponds to PRACH resources on a second initial uplink BWP;

[0044] the first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format;

[0045] the first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group; and

[0046] wherein the first PRACH parameter and the second PRACH parameter include at least one of the following parameters:

[0047] a parameter related to a position of a time unit for a PRACH;

[0048] a parameter related to a position of a frequency domain resource for a PRACH;

[0049] a subcarrier spacing for a PRACH;

[0050] an index of a PRACH configuration;

[0051] a cyclic shift value of the PRACH preamble;

[0052] a root sequence index of the PRACH preamble;

[0053] a parameter related to transmission power of a PRACH;

[0054] a threshold value or range for the size of a Message 3 in the random access procedure for selecting a PRACH resource set; and

[0055] a threshold value or range for reference signal received power (RSRP) of downlink pathloss reference for selecting a PRACH resource set.

[0056] Optionally, the PRACH resource set includes at least one of the following:

[0057] a set of a part of ROs in the PRACH resource pool;

[0058] a set of a part of PRACH time units in the PRACH resource pool;

[0059] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0060] a set of a part of PRACH preambles in the PRACH resource pool; and

[0061] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0062] Optionally, the first signal is carried by at least one of the following physical signals or physical channels:

[0063] an uplink physical signal;

[0064] a PRACH; and

[0065] a physical uplink control channel (PUCCH).

[0066] Optionally, the first signal carries first information related to the PRACH resource set to be activated by request, the first information includes at least one of the following:

[0067] information related to a PRACH configuration corresponding to the PRACH resource set to be activated by request;

[0068] information related to a PRACH parameter corresponding to the PRACH resource set to be activated by request;

[0069] information related to an uplink carrier corresponding to the PRACH resource set to be activated by request;

[0070] information related to an initial uplink BWP corresponding to the PRACH resource set to be activated by request;

[0071] information related to a PRACH group corresponding to the PRACH resource set to be activated by request;

[0072] information related to a PRACH format corresponding to the PRACH resource set to be activated by request;

[0073] an index of the PRACH resource set to be activated by request; and / or

[0074] the first signal carries second information related to assisting a base station to activate the PRACH resource set, and the second information includes at least one of the following:

[0075] a type of the UE;

[0076] a size of a Message 3 in the random access procedure;

[0077] a RSRP value of a downlink pathloss reference;

[0078] a priority of arriving data;

[0079] a type of the arriving data;

[0080] an index of a logical channel or a logical channel group (LCH) where the arriving data is located;

[0081] a size of data amount of the arriving data;

[0082] remaining packet delay budget (PDB) of the arriving data; and

[0083] an event for triggering the random access procedure.

[0084] Optionally, the second signal is carried by at least one of the following physical signals or physical channels:

[0085] a downlink physical signal;

[0086] a physical broadcast channel (PBCH);

[0087] a physical downlink control channel (PDCCH); and

[0088] medium access control (MAC) layer signal.

[0089] Optionally, the PDCCH includes at least one of the following:

[0090] a PDCCH scrambled with a dedicated radio network temporary identity (RNTI);

[0091] a PDCCH for scheduling a random access response physical downlink shared channel (PDSCH);

[0092] a PDCCH for scheduling a system information PDSCH; and

[0093] a PDCCH for scheduling a paging message PDSCH.

[0094] The MAC layer signal includes at least one of the following:

[0095] a MAC subheader included in a MAC protocol data unit (PDU) for carrying the random access response (RAR); and

[0096] a MAC RAR.

[0097] Optionally, information indicating that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, which is included in the second signal, or information indicating that one or more PRACH resource sets are activated, which is included in the second signal, includes at least one of the following:

[0098] information related to PRACH configurations respectively corresponding to one or more activated PRACH resource sets;

[0099] information related to PRACH parameters respectively corresponding to one or more activated PRACH resource sets;

[0100] information related to uplink carriers respectively corresponding to one or more activated PRACH resource sets;

[0101] information related to initial uplink BWPs respectively corresponding to one or more activated PRACH resource sets;

[0102] information related to PRACH groups respectively corresponding to one or more activated PRACH resource sets;

[0103] information related to PRACH formats respectively corresponding to one or more activated PRACH resource sets;

[0104] indexes of one or more activated PRACH resource sets; and

[0105] bitmap information for indicating whether a plurality of PRACH resource sets are activated or not, respectively.

[0106] Optionally, the method further includes:

[0107] after transmitting the first signal, monitoring the second signal at a first position meeting a first preset interval, or within a first time window from the first position, or on a first transmission opportunity for the second signal after the first position.

[0108] Optionally, the method further includes:

[0109] determining a second time window where the first signal is located, wherein the second time window includes a plurality of transmission opportunities for the first signal;

[0110] after an ending position of the second time window, monitoring the second signal at a second position meeting a second preset interval, or within a first time window from the second position, or on a first transmission opportunity for the second signal after the second position.

[0111] Optionally, if the second signal has not been monitored, or if the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated, the method further includes performing at least one of the following:

[0112] initiating the random access procedure based on the first PRACH resource set;

[0113] continuing to attempt to transmit the first signal on a next transmission opportunity for the first signal, and if the second signal has not been monitored yet after a maximum number of attempts is reached, or the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated, reporting error information to a higher layer; and

[0114] continuing to attempt to transmit the first signal on a next transmission opportunity for the first signal, and if the second signal has not been monitored yet after a maximum number of attempts is reached, or the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated, initiating the random access procedure based on the first PRACH resource set.

[0115] Optionally, if the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, initiating the random access procedure based on the activated PRACH resource set, includes performing at least one of the following:

[0116] initiating the random access procedure based on the activated PRACH resource set.

[0117] initiating the random access procedure based on an union of the first PRACH resource set and the activated PRACH resource set.

[0118] Optionally, in case where the random access procedure is initiated based on the union of the first PRACH resource set and the activated PRACH resource set, probabilities which the first PRACH resource set and the activated PRACH resource set are selected are configured separately.

[0119] Optionally, the method further includes:

[0120] initiating the random access procedure based on a default PRACH resource set, if the second signal has not been monitored, or if the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated; and

[0121] initiating the random access procedure based on the activated PRACH resource set, if the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated;

[0122] wherein the default PRACH resource set is a subset of the activated PRACH resource set.

[0123] Optionally, the activation period is obtained by at least one of the following:

[0124] the preset length of the time period is pre-configured by higher layer signal;

[0125] the preset length of the time period is indicated by the second signal;

[0126] the first preset number of the consecutive ROs is pre-configured by the higher layer signal;

[0127] the first preset number of the consecutive ROs is indicated by the second signal;

[0128] the preset maximum number of PRACH preamble transmission is pre-configured by higher layer signal; and

[0129] the preset maximum number of PRACH preamble transmission is indicated by the second signal.

[0130] Optionally, the starting position of the activation period includes at least one of the following:

[0131] a position meeting a third preset interval after the first signal is transmitted;

[0132] a starting position of a first available RO meeting the third preset interval after the first signal is transmitted;

[0133] a position meeting a fourth preset interval after the second signal is received; and

[0134] a starting position of a first available RO meeting the fourth preset interval after the second signal is received.

[0135] Optionally, during the activation period, a maximum number of PRACH preambles transmitted based on the PRACH resource set to be activated by the first requesting and / or assisting is determined based on a duration of the activation period.

[0136] Optionally, the method further includes:

[0137] initiating the random access procedure based on a first PRACH resource set, if the random access is not successful after the end of the activation period.

[0138] Optionally, in case that the first signal is carried by a PRACH,

[0139] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure are configured by different radio resource control information units, respectively;

[0140] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure are obtained by division of the PRACH resource pool; and

[0141] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources.

[0142] Optionally, in case that the PRACH resources for carrying the first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources, the shared PRACH resources belong to the first PRACH resource set.

[0143] Optionally, the method further includes:

[0144] initiating the random access procedure based on the shared PRACH resources; and

[0145] initiating the random access procedure based on the PRACH resource set which is activated based on the shared PRACH resources by request, if the random access is not successful.

[0146] Optionally, the method further includes:

[0147] after the random access procedure is initiated based on the shared PRACH resources, receiving a Message 2 including information on the PRACH resource sets being activated; and

[0148] initiating the random access procedure based on the activated PRACH resource sets indicated by the Message 2, if the random access is not successful.

[0149] Optionally, the UE is triggered to transmit the first signal when at least one of the following conditions is met:

[0150] a request or an indication from a higher layer is received, wherein the request or the indication is about transmitting the first signal or initiating the random access procedure;

[0151] the random access procedure is initiated;

[0152] a size of a Message 3 in the random access procedure is greater than or equal to a first preset threshold value;

[0153] the size of the Message 3 in the random access procedure is within a first preset range;

[0154] a RSRP value of the downlink pathloss reference is less than the a second preset threshold value;

[0155] the RSRP value of the downlink pathloss reference is within a second preset range;

[0156] an event for triggering the random access procedure is a preset event;

[0157] a priority of an arriving data is lower than a preset priority;

[0158] type of the arriving data is of a preset type;

[0159] an index of a logical channel where the arriving data is located or an index of a logical channel group where the arriving data is located is a preset index;

[0160] a size of data amount of the arriving data is greater than or equal to a third preset threshold value;

[0161] remaining packet delay budget of the arriving data is less than a fourth preset threshold value, or the remaining packet delay budget of the arriving data is greater than or equal to the fourth preset threshold value; and

[0162] the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches a second preset number.

[0163] Optionally, the condition for triggering the UE to transmit the first signal is configured by the system information or configured by the UE specific RRC signal.

[0164] Optionally, the UE is a UE of a preset type and / or a UE supporting a preset capability.

[0165] In accordance with another aspect of the embodiments of the present disclosure, there is provided another method performed by UE in a communication system, the method includes:

[0166] receiving a third signal, the third signal including information related to activation or deactivation of the PRACH resource set;

[0167] during an activation period of the PRACH resource set, initiating the random access procedure based on the activated PRACH resource set;

[0168] wherein the activation period includes at least one of the following:

[0169] the activation period including a time period with a preset length;

[0170] the activation period including a first preset number of consecutive ROs; and

[0171] the activation period including a preset maximum number of PRACH preamble transmission.

[0172] Optionally, the activation period is obtained by at least one of the following:

[0173] the preset length of the time period is pre-configured by higher layer signal;

[0174] the preset length of the time period is indicated by the third signal;

[0175] the first preset number of the consecutive ROs is pre-configured by the higher layer signal;

[0176] the first preset number of the consecutive ROs is indicated by the third signal;

[0177] the preset maximum number of PRACH preamble transmission is pre-configured by higher layer signal; and

[0178] the preset maximum number of PRACH preamble transmission is indicated by the third signal.

[0179] Optionally, prior to receiving the third signal, the method further includes:

[0180] receiving configuration information related to the first PRACH resource set and the second PRACH resource set, wherein the second PRACH resource set needs to be activated for use, the second PRACH resource set can be indicated to be activated or deactivated by the third signal; and

[0181] wherein the first PRACH resource set includes one or more PRACH resource sets, and the second PRACH resource set includes one or more PRACH resource sets.

[0182] Optionally, the first PRACH resource set is associated with a synchronization signal block (SSB) based on a first parameter;

[0183] the second PRACH resource set is associated with a SSB based on a second parameter; and

[0184] wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is the number of SSBs being mapped to each RO and / or the number of contention-based PRACH preambles being mapped to each SSB.

[0185] Optionally, if the second PRACH resource set is not activated, the first PRACH resource set is associated with a SSB based on a third parameter;

[0186] in case that the second PRACH resource set is activated, the union of the first PRACH resource set and the second PRACH resource set is associated with a SSB based on the third parameter; and

[0187] wherein the third parameter is the number of SSBs being mapped to each random access occasion (RO), and / or the number of the contention-based PRACH preambles being mapped to each SSB.

[0188] Optionally, the first PRACH resource set is configured by a first radio resource control information unit; and

[0189] the second PRACH resource set is configured by a second radio resource control information unit;

[0190] wherein the first radio resource control information unit and the second radio resource control information unit are configured by the system information; or

[0191] the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by UE specific radio resource control (RRC) signal.

[0192] Optionally, the first PRACH resource set and the second PRACH resource set are obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit.

[0193] Optionally, configuration information for the first PRACH resource set and the second PRACH resource set includes at least one of the following:

[0194] the first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning;

[0195] the first PRACH resource set corresponds to the PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to the PRACH resources on a second uplink carrier;

[0196] the first PRACH resource set corresponds to the PRACH resources on a first initial uplink bandwidth part (BWP), and the second PRACH resource set corresponds to the PRACH resources on a second initial uplink BWP;

[0197] the first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format;

[0198] the first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group; and

[0199] wherein the first PRACH parameter and the second PRACH parameter include at least one of the following parameters:

[0200] a parameter related to a position of a time unit for a PRACH;

[0201] a parameter related to a position of a frequency domain resource for a PRACH;

[0202] a subcarrier spacing for a PRACH;

[0203] an index of a PRACH configuration;

[0204] a cyclic shift value of the PRACH preamble;

[0205] a root sequence index of the PRACH preamble;

[0206] a parameter related to transmission power of a PRACH;

[0207] a threshold value or range for the size of a Message 3 in the random access procedure for selecting a PRACH resource set; and

[0208] a threshold value or range for reference signal receiving power (RSRP) of downlink pathloss reference for selecting a PRACH resource set.

[0209] Optionally, the PRACH resource set includes at least one of the following:

[0210] a set of a part of ROs in the PRACH resource pool;

[0211] a set of a part of PRACH time units in the PRACH resource pool;

[0212] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0213] a set of a part of PRACH preambles in the PRACH resource pool; and

[0214] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0215] Optionally, initiating a random access procedure based on the activated PRACH resource sets, includes:

[0216] initiating the random access procedure based on the first PRACH resource set, if the second PRACH resource set is not activated;

[0217] performing at least one of the following, if the second PRACH resource set is activated:

[0218] initiating the random access procedure based on the activated second PRACH resource set;

[0219] initiating the random access procedure based on the union of the first PRACH resource set and the activated second PRACH resource set;

[0220] initiating the random access procedure based on the activated second PRACH resource set; and initiating the random access procedure based on the first PRACH resource set, if the random access is not successful after the activation period of the second PRACH resource set; and

[0221] initiating the random access procedure based on the first PRACH resource set; and initiating the random access procedure based on the activated second PRACH resource set, if the random access is not successful after a number of PRACH preamble transmission reaches a preset maximum number.

[0222] Optionally, in case where the random access procedure is initiated based on the union of the first PRACH resource set and the activated second PRACH resource set, the probabilities the first PRACH resource set and the activated second PRACH resource set are selected are configured separately.

[0223] Optionally, information related to activation or deactivation of the PRACH resource set includes at least one of the following:

[0224] information related to the PRACH configurations corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0225] information related to PRACH parameters corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0226] information related to uplink carriers corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0227] information related to an initial uplink BWP corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0228] information related to PRACH groups corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0229] information related to PRACH formats corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0230] indexes of one or more activated or deactivated PRACH resource sets; and

[0231] bitmap information for indicating whether a plurality of PRACH resource sets are activated or not, respectively.

[0232] Optionally, the PRACH resource set includes at least one of the following:

[0233] a set of a part of ROs in the PRACH resource pool;

[0234] a set of a part of PRACH time units in the PRACH resource pool;

[0235] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0236] a set of a part of PRACH preambles in the PRACH resource pool; and

[0237] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0238] Optionally, the third signal is carried by at least one of the following signal:

[0239] a physical broadcast channel (PBCH);

[0240] a physical downlink control channel PDCCH for scheduling a random access response physical downlink shared channel PDSCH;

[0241] a PDCCH for scheduling a system information PDSCH; and

[0242] a PDCCH for scheduling a paging message PDSCH.

[0243] a PDCCH scrambled with a dedicated radio network temporary identity (RNTI); and

[0244] a downlink control information (DCI) scrambled with a cell radio network temporary identity (C-RNTI) for scheduling PDSCH or physical uplink shared channel PUSCH.

[0245] Optionally, the activation period includes at least one of the following:

[0246] the size of the activation period is the size of the transmission period of the third signal;

[0247] the starting position of the activation period is the starting position of the transmission period of the third signal;

[0248] the starting position of the activation period is a position meeting a fifth preset interval after the third signal is received; and

[0249] the starting position of the activation period is a starting position of a first available RO meeting the fifth preset interval after the third signal is received.

[0250] Optionally, the third signal is transmitted periodically, the method further includes at least one of the following:

[0251] monitoring the third signal on each transmission opportunity for the third signal; and

[0252] when a preset condition is satisfied, monitoring the third signal within the following time period of a preset length, or monitoring the third signal within the following earliest transmission opportunity for the third signal.

[0253] Optionally, the method further includes:

[0254] initiating the random access procedure based on the first PRACH resource set, if the third signal has not been monitored.

[0255] Optionally, the preset condition includes at least one of the following:

[0256] a request or an indication from a higher layer is received, wherein the request or the indication is about monitoring the third signal or initiating the random access procedure;

[0257] the random access procedure is initiated;

[0258] the size of a Message 3 in the random access procedure is greater than or equal to a first preset threshold value;

[0259] the size of a Message 3 in the random access procedure is within a first preset range;

[0260] the RSRP value of the downlink pathloss reference is less than the a second preset threshold value;

[0261] the RSRP value of the downlink pathloss reference is within a second preset range;

[0262] the event for triggering the random access procedure is a preset event;

[0263] the priority of the arriving data is lower than a preset priority;

[0264] the type of the arriving data is of a preset type;

[0265] the index of a logical channel where the arriving data is located or the index of a logical channel group where the arriving data is located is a preset index;

[0266] the size of the amount of the arriving data is greater than or equal to a third preset threshold value;

[0267] the remaining packet delay budget of the arriving data is less than a fourth preset threshold value, or the remaining packet delay budget of the arriving data is greater than or equal to the fourth preset threshold value; and

[0268] the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches a second preset number.

[0269] Optionally, the condition for triggering the UE to monitor the third signal is configured by the system information or configured by the UE specific RRC signal.

[0270] Optionally, the UE is a UE of a preset type and / or a UE supporting a preset capability.

[0271] In accordance with yet another aspect of the embodiments of the present disclosure, a method performed by a base station in a communication system is provided, the method includes:

[0272] receiving a first signal transmitted by a UE, the first signal including information related to requesting and / or assisting to activate a physical random access channel (PRACH) resource set;

[0273] transmitting, to the UE, a second signal, the second signal is used for confirming that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or the second signal includes information indicating that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated,

[0274] wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the PRACH resource set activated by the first signal requesting and / or assisting;

[0275] the activation period includes at least one of the following:

[0276] the activation period including a time period with a preset length;

[0277] the activation period including a first preset number of consecutive random access occasions (ROs); and

[0278] the activation period including a preset maximum number of PRACH preamble transmission.

[0279] In accordance with yet another aspect of the embodiments of the present disclosure, a method performed by a base station in a communication system is provided, the method includes:

[0280] transmitting, to the UE, a third signal, the third signal including information related to activation or deactivation of the PRACH resource set;

[0281] wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the activated PRACH resource sets;

[0282] the activation period includes at least one of the following:

[0283] the activation period including a time period with a preset length;

[0284] the activation period including a first preset number of consecutive random access occasions (ROs); and

[0285] the activation period including a preset maximum number of PRACH preamble transmission.

[0286] In accordance with still another aspect of the embodiments of the present disclosure, a user equipment is provided, including:

[0287] a transceiver; and

[0288] a processor, which is coupled to the transceiver and configured to execute the method performed by the UE in a communication system provided in the embodiments of the present disclosure.

[0289] In accordance with still another aspect of the embodiments of the present disclosure, a base station is provided, including:

[0290] a transceiver; and

[0291] a processor, which is coupled to the transceiver and configured to execute the method performed by the base station in a communication system provided in the embodiments of the present disclosure.

[0292] In accordance with still another aspect of the embodiments of the present disclosure, a computer-readable storage medium is provided, the computer-readable storage medium having computer programs stored thereon that, when executed by a processor, implement the method performed by a UE or base station in a communication system provided in the embodiments of the present disclosure.

[0293] In accordance with still another aspect of the embodiments of the present disclosure, a computer program product is provided, including computer programs that, when executed by a processor, implement the method performed by a UE or base station in a communication system provided in the embodiments of the present disclosure.

[0294] In the random access method, the user equipment and the base station provided in embodiments of the present disclosure, the UE transmits the first signal, the first signal including information related to requesting and / or assisting activation of a physical random access channel (PRACH) resource set; during the activation period of the PRACH resource set, the random access procedure is initiated based on the PRACH resource set activated by the first signal requesting and / or assisting; the activation period includes at least one of the following: a time period with a preset length, a first preset number of consecutive ROs, and a preset maximum number of PRACH preamble transmission. That is, the configured PRACH resources need to be activated for use, it can be guaranteed that the number of activated PRACH resources is matched with the real-time load on the network, thereby avoiding the waste of the PRACH resources and achieving efficient utilization of the PRACH resources.

[0295] Before undertaking the DETAILED DESCRIPTION below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document. The term "couple" and its derivatives refer to any direct or indirect communication between two or more elements, whether those elements are in physical contact with one another. The terms "transmit," "receive," and "communicate," as well as derivatives thereof, encompass both direct and indirect communication. The terms "include" and "comprise," as well as derivatives thereof, mean inclusion without limitation. The term "or" is inclusive, meaning and / or. The phrase "associated with," as well as derivatives thereof, means to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, have a relationship to or with, or the like. The term "controller" means any device, system or part thereof that controls at least one operation. Such a controller may be implemented in hardware or a combination of hardware and software and / or firmware. The functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. The phrase "at least one of," when used with a list of items, means that different combinations of one or more of the listed items may be used, and only one item in the list may be needed. For example, "at least one of A, B, and C" includes any of the following combinations: A, B, C, A and B, A and C, B and C, and A and B and C. Likewise, the term "set" means one or more. Accordingly, a set of items may be a single item or a collection of two or more items.

[0296] Moreover, various functions described below may be implemented or supported by one or more computer programs, each of which is formed from computer readable program code and embodied in a computer readable medium. The terms "application" and "program" refer to one or more computer programs, software components, sets of instructions, procedures, functions, objects, classes, instances, related data, or a portion thereof adapted for implementation in a suitable computer readable program code. The phrase "computer readable program code" includes any type of computer code, including source code, object code, and executable code. The phrase "computer readable medium" includes any type of medium capable of being accessed by a computer, such as read only memory (ROM), random access memory (RAM), a hard disk drive, a compact disc (CD), a digital video disc (DVD), or any other type of memory. A "non-transitory" computer readable medium excludes wired, wireless, optical, or other communication links that transport transitory electrical or other signals. A non-transitory computer readable medium includes media where data may be permanently stored and media where data may be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.

[0297] Definitions for other certain words and phrases are provided throughout this patent document. Those of ordinary skill in the art should understand that in many if not most instances, such definitions apply to prior as well as future uses of such defined words and phrases.

[0298] The figures included herein, and the various embodiments used to describe the principles of the present disclosure are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Further, those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged wireless communication system.

[0299] FIGs. 1-3 below describe various embodiments of the present disclosure implemented in wireless communication systems. The descriptions of FIGS. 1-3 are not meant to imply physical or architectural limitations to the manner in which different embodiments may be implemented. Different embodiments of the present disclosure may be implemented in any suitably-arranged communication system.

[0300] FIG. 1 illustrates an example wireless network according to embodiments of the present disclosure. The embodiment of the wireless network shown in FIG. 1 is for illustration only. Other embodiments of the wireless network 100 could be used without departing from the scope of the present disclosure.

[0301] As shown in FIG. 1, the wireless network includes a base station (Next Generation Nodeb, gNB or GNodeB) 101, a gNB 102, and a gNB 103. The gNB 101 communicates with the gNB 102 and the gNB 103. The gNB 101 also communicates with at least one network 130, such as the Internet, a proprietary Internet Protocol (IP) network, or other data network.

[0302] The gNB 102 provides wireless broadband access to the network 130 for a plurality of first user equipments (UEs) within a coverage area 120 of the gNB 102. The plurality of first UEs include a UE 111, which may be located in a small business (SB); a UE 112, which may be located in an enterprise (E); a UE 113, which may be located in a WiFi hotspot (HS); a UE 114, which may be located in a first residence (R1); a UE 115, which may be located in a second residence (R2); and a UE 116, which may be a mobile device (M), such as a cell phone, a wireless laptop, a wireless personal digital assistant (PDA), or the like. The gNB 103 provides wireless broadband access to the network 130 for a plurality of second UEs within a coverage area 125 of the gNB 103. The plurality of second UEs include the UE 115 and the UE 116, as well as subscriber stations (SS, for example, UEs) 117, 118 and 119. In some embodiments, one or more of the gNBs 101-103 may communicate with each other and with the UEs 111-116 using existing wireless communication techniques, and one or more of the UE 111-119 may communicate directly with each other (e.g., UEs 117-119) using other existing or proposed wireless communication techniques.

[0303] Depending on the network type, the term "base station" or "BS" may refer to any component (or collection of components) configured to provide wireless access to a network, such as transmit point (TP), transmit-receive point (TRP), an enhanced (or "evolved") base station (eNodeB or eNB), a 5G base station (gNB), a macrocell, a femtocell, a wireless fidelity (WiFi) access point (AP), or other wirelessly enabled devices. Base stations may provide wireless access in accordance with one or more wireless communication protocols, e.g., 3GPP 5G New Radio (NR), Long Term Evolution (LTE), LTE Advanced (LTE-A), high speed packet access (HSPA), Wi-Fi 802.11a / b / g / n / ac, etc. For the sake of convenience, the various names for a base station-type apparatus and functionality are used interchangeably in this patent document to refer to network infrastructure components that provide wireless access to remote terminals. Also, depending on the network type, the term "user equipment" (UE) may refer to any component such as a mobile station (MS), subscriber station (SS), remote terminal, wireless terminal, receive point, or user device. For the sake of convenience, the various names for a user equipment-type device and functionality are used interchangeably in this patent document to refer to remote wireless equipment that wirelessly accesses a BS, whether the UE is a mobile device (such as a mobile telephone or smartphone) or is normally considered a stationary device (such as a desktop computer or vending machine).

[0304] Dotted lines show the approximate extents of the coverage areas 120 and 125, which are shown as approximately circular for the purposes of illustration and explanation only. It should be clearly understood that the coverage areas associated with gNBs , such as the coverage areas 120 and 125, may have other shapes, including irregular shapes, depending upon the configuration of the gNBs and variations in the radio environment associated with natural and man-made obstructions.

[0305] As described in more detail below, one or more of the UEs 111-119 include circuitry, programing, or a combination thereof. In certain embodiments, and one or more of the gNBs 101-103 includes circuitry, programing, or a combination thereof.

[0306] Although FIG. 1 illustrates one example of a wireless network, various changes may be made to FIG. 1. For example, the wireless network 100 could include any number of gNBs and any number of UEs in any suitable arrangement. Also, the gNB 101 could communicate directly with any number of UEs and provide those UEs with wireless broadband access to the network 130. Similarly, each gNB 102-103 could communicate directly with the network 130 and provide UEs with direct wireless broadband access to the network 130. Further, the gNBs 101, 102, and / or 103 could provide access to other or additional external networks, such as external telephone networks or other types of data networks.

[0307] FIG. 2 illustrates an example base station according to embodiments of the present disclosure. The embodiment of the gNB 102 illustrated in FIG. 2 is for illustration only, and the gNBs 101 and 103 of FIG. 1 could have the same or similar configuration. However, gNBs come in a wide variety of configurations, and FIG. 2 does not limit the scope of the present disclosure to any particular implementation of a gNB.

[0308] As shown in FIG 2, the gNB 102 includes multiple antennas 200a-200n, multiple radio frequency (RF) transceivers 201a-201n, a transmit (TX) processing circuitry 203, and a receive (RX) processing circuitry 204. The gNB 102 also includes a controller / processor 205, a memory 206, and a backhaul or network interface (IF) 207.

[0309] The RF transceivers 201a-201n receive, from the antennas 200a-200n, incoming RF signals, such as signals transmitted by UEs in the network 100. The RF transceivers 201a-201n down-convert the incoming RF signals to generate intermediate frequency (IF) or baseband signals. The IF or baseband signals are transmitted to the RX processing circuitry 204, which generates processed baseband signals by filtering, decoding, and / or digitizing the baseband or IF signals. The RX processing circuitry 204 transmits the processed baseband signals to the controller / processor 205 for further processing.

[0310] The TX processing circuitry 203 receives analog or digital data (such as voice data, web data, electronic mail, or interactive video game data) from the controller / processor 205. The TX processing circuitry 203 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate processed baseband or IF signals. The RF transceivers 201a-201n receive the outgoing processed baseband or IF signals from the TX processing circuitry 203 and up-converts the baseband or IF signals to RF signals that are transmitted via the antennas 201a-201n.

[0311] The controller / processor 205 may include one or more processors or other processing devices that control the overall operation of the gNB 102. For example, the controller / processor 205 could control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceivers 201a-201n, the RX processing circuitry 204, and the TX processing circuitry 203 in accordance with well-known principles. The controller / processor 205 could support additional functions as well, such as more advanced wireless communication functions.

[0312] For instance, the controller / processor 205 could support beam forming or directional routing operations in which outgoing signals from multiple antennas 200a-200n are weighted differently to effectively steer the outgoing signals in a desired direction. Any of a wide variety of other functions could be supported in the gNB 102 by the controller / processor 205.

[0313] The controller / processor 205 is also capable of executing programs and other processes resident in the memory 206, such as an operating system (OS). The controller / processor 205 may move data into or out of the memory 206 as required by an executing process.

[0314] The controller / processor 205 is also coupled to the backhaul or network interface 207. The backhaul or network interface 207 allows the gNB 102 to communicate with other devices or systems over a backhaul connection or over a network. The interface 207 could support communications over any suitable wired or wireless connection(s). For example, when the gNB 102 is implemented as part of a cellular communication system (such as one supporting 5G, LTE, or LTE-A), the interface 207 could allow the gNB 102 to communicate with other gNBs over a wired or wireless backhaul connection. When the gNB 102 is implemented as an access point, the interface 207 could allow the gNB 102 to communicate over a wired or wireless local area network or over a wired or wireless connection to a larger network (such as the Internet). The interface 207 includes any suitable structure supporting communications over a wired or wireless connection, such as an Ethernet or RF transceiver.

[0315] The memory 206 is coupled to the controller / processor 205. Part of the memory 206 could include a random access memory (RAM), and another part of the memory 206 could include a Flash memory or other read only memory (ROM).

[0316] Although FIG. 2 illustrates one example of gNB 102, various changes may be made to FIG. 2. For example, the gNB 102 could include any number of each component shown in FIG. 2. As a particular example, an access point could include a number of interfaces 207, and the controller / processor 205 could support routing functions to route data between different network addresses. As another particular example, while shown as including a single instance of TX processing circuitry 203 and a single instance of RX processing circuitry 204, the gNB 102 could include multiple instances of each (such as one per RF transceiver). Also, various components in FIG. 2 could be combined, further subdivided, or omitted and additional components could be added according to particular needs.

[0317] FIG. 3 illustrates an example user equipment according to embodiments of the present disclosure. The embodiment of the UE 116 illustrated in FIG. 3 is for illustration only, and the UEs 111-115 and 117-119 of FIG. 1 could have the same or similar configuration. However, UEs come in a wide variety of configurations, and FIG. 3 does not limit the scope of the present disclosure to any particular implementation of a UE.

[0318] As shown in FIG. 3, the UE 116 includes an antenna 301, a radio frequency (RF) transceiver 302, TX processing circuitry 303, a microphone 304, and receive (RX) processing circuitry 305. The UE 116 also includes a speaker 306, a controller or processor 307, an input / output (I / O) interface (IF) 308, an input device 309, a touchscreen display 310, and a memory 311. The memory 311 includes an OS 312 and one or more applications 313.

[0319] The RF transceiver 302 receives, from the antenna 301, an incoming RF signal transmitted by an gNB of the network 100. The RF transceiver 302 down-converts the incoming RF signal to generate an IF or baseband signal. The IF or baseband signal is transmitted to the RX processing circuitry 305, which generates a processed baseband signal by filtering, decoding, and / or digitizing the baseband or IF signal. The RX processing circuitry 305 transmits the processed baseband signal to the speaker 306 (such as for voice data) or to the processor 307 for further processing (such as for web browsing data).

[0320] The TX processing circuitry 303 receives analog or digital voice data from the microphone 304 or other outgoing baseband data (such as web data, e-mail, or interactive video game data) from the processor 307. The TX processing circuitry 303 encodes, multiplexes, and / or digitizes the outgoing baseband data to generate a processed baseband or IF signal. The RF transceiver 302 receives the outgoing processed baseband or IF signal from the TX processing circuitry 303 and up-converts the baseband or IF signal to an RF signal that is transmitted via the antenna 301.

[0321] The processor 307 may include one or more processors or other processing devices and execute the OS 312 stored in the memory 311 in order to control the overall operation of the UE 116. For example, the processor 307 could control the reception of forward channel signals and the transmission of reverse channel signals by the RF transceiver 302, the RX processing circuitry 305, and the TX processing circuitry 303 in accordance with well-known principles. In some embodiments, the processor 307 includes at least one microprocessor or microcontroller.

[0322] The processor 307 is also capable of executing other processes and programs resident in the memory 311, such as processes for CSI (Channel State Information) reporting on uplink channel. The processor 307 may move data into or out of the memory 311 as required by an executing process. In some embodiments, the processor 307 is configured to execute the applications 313 based on the OS 312 or in response to signals received from gNBs or an operator. The processor 307 is also coupled to the I / O interface 308, which provides the UE 116 with the ability to connect to other devices, such as laptop computers and handheld computers. The I / O interface 308 is the communication path between these accessories and the processor 307.

[0323] The processor 307 is also coupled to the touchscreen display 310. The user of the UE 116 may use the touchscreen display 310 to enter data into the UE 116. The touchscreen display 310 may be a liquid crystal display, a light emitting diode display, or other displays capable of rendering text and / or at least limited graphics, such as from web sites.

[0324] The memory 311 is coupled to the processor 307. Part of the memory 311 could include RAM, and another part of the memory 311 could include a Flash memory or other ROM.

[0325] Although FIG. 3 illustrates one example of UE 116, various changes may be made to FIG. 3. For example, various components in FIG. 3 could be combined, further subdivided, or omitted and additional components could be added according to particular needs. As a particular example, the processor 307 could be divided into multiple processors, such as one or more central processing units (CPUs) and one or more graphics processing units (GPUs). Also, while FIG. 3 illustrates the UE 116 configured as a mobile telephone or smartphone, UEs could be configured to operate as other types of mobile or stationary devices.

[0326] To make the objectives, technical solutions and advantages of the present disclosure clearer, the technical solutions of the embodiments of the present disclosure and the technical effects generated by the technical solutions of the present disclosure are described below through the description of several exemplary embodiments. It is to be noted that the following embodiments may refer to or be learned from each other or be combined with each other, and the same terms, similar features and similar implementation steps in different embodiments will not be repeated.

[0327] In embodiments of the present disclosure, there is provided an on-demand PRACH. The UE transmits, to the base station, a first signal to request and / or assist to activate the pre-configured PRACH resource sets, and such PRACH resource sets to be activated by signal requesting and / or assisting may be referred to as on-demand PRACH.

[0328] The PRACH resource set refers to a set including a group of PRACH resources, which may also be referred to as a PRACH resource collection. With respect to the PRACH resource pool, a PRACH resource set may also be referred to as a PRACH resource subpool or a PRACH resource subset. A PRACH resource set may be a part of PRACH resources in a PRACH resource pool. For example, a plurality of PRACH resource sets are configured by partitioning a large PRACH resource pool. A PRACH resource pool refers to a large pool or set of the PRACH resources corresponding to all PRACH preambles on all PRACH frequency domain resources on all PRACH time slots determined by configuration parameters. For example, partition on the PRACH resource pool may be performed in the code domain (i.e., the PRACH preamble), the time domain and / or the frequency domain. In this case, a PRACH resource set may also be referred to as a PRACH resource subset, or a PRACH resource partition.

[0329] Optionally, the PRACH resource set includes, but not limited to, at least one of the following:

[0330] (1) a set of a part of RACH occasions (ROs) in the PRACH resource pool, i.e., a set of PRACH resources on a group of ROs;

[0331] (2) a set of a part of PRACH time units in the PRACH resource pool, for example, the time unit may refer specifically to the time domain, i.e., a set of PRACH resources on a group of PRACH time slots;

[0332] (3) a set of a part of PRACH frequency domain resources in the PRACH resource pool, i.e., a set of PRACH resources on a group of PRACH frequency domain resources;

[0333] (4) a set of a part of PRACH preambles in the PRACH resource pool, i.e., a set of PRACH resources corresponding to a group of PRACH preambles; and

[0334] (5) a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool, i.e., a set of PRACH resources correspond to a part of PRACH preambles on a group of ROs.

[0335] In an embodiment of the present disclosure, there is provided a method performed by a UE in a communication system. As shown in FIG. 4, the method includes the following steps.

[0336] Step S101: transmitting a first signal, the first signal including information related to requesting and / or assisting to activate the PRACH resource set; and

[0337] Step S102: during an activation period of the PRACH resource set, initiating a random access procedure, based on the PRACH resource set to be activated by the first signal requesting and / or assisting.

[0338] That UE initiating the random access procedure may also be construed as the UE and the base station conducting the random access procedure or performing the random access procedure.

[0339] In order to utilize the PRACH resources efficiently, the PRACH resources configured by the base station (i.e., the network) need to be activated for use, including but not limited to the cell-specific PRACH resources configured by the system information and / or the dedicated PRACH resources configured by the UE specific signal, etc. That is, the configuring the PRACH resources does not mean that the PRACH resources are valid, and the PRACH resources need to be further activated to be valid. If the configured PRACH resources are not activated, these configured PRACH resources cannot be used by the UE.

[0340] The advantage of this approach is that the number of the activated PRACH resources is matched to the real-time load on the network, thereby avoiding the waste of PRACH resources and the congestion of the network access as well and achieving efficient utilization of the PRACH resources.

[0341] The first signal may be construed as a requesting signal, for example, the first signal is used for requesting the activation of the pre-configured PRACH resource sets, i.e., the first signal corresponds to a piece of state information. Alternatively, the first signal is used for requesting the activation one of a plurality of pre-configured PRACH resource sets, i.e., the first signal corresponds to information of at least one bit. Alternatively, the first signal may also be construed as an assistance signal, for example, the first signal is used for reporting some information of the UE to assist the base station for determining whether to activate one or more of the pre-configured PRACH resource sets or not, i.e., the first signal corresponds to information of at least one bit.

[0342] In an embodiment of the present disclosure, optional implementations for activation of the PRACH resource sets are provided.

[0343] In an optional implementation, the UE assumes that the PRACH resource set to be activated by request and / or in an assisted manner is activated without receiving a confirmation signal from the base station, and UE may perform the step S102 immediately after the above step S101 is performed. For example, the UE starts to assume that the PRACH resource set to be activated by requesting and / or assisting is activated from a preset interval position after the first signal is transmitted.

[0344] In another optional implementation, the base station may determine whether to activate a part of or all of the pre-configured PRACH resources or not, depending on the condition of the real-time load on the network (e.g., the magnitude of the UEs that initiate the random access). For example, when the real-time load on the network is small (e.g., the number of UEs that initiate the random access is small), the base station may active only a small portion of the PRACH resources; and when the real-time load on the network is large (e.g., the number of UEs that initiate the random access is large), the base station may activate most of or all of the PRACH resources.

[0345] In an embodiment of the present disclosure, the base station transmits a second signal to the UE after receiving the first signal (the requesting signal). Then Step S102 may include: the UE receives the second signal from the base station, the second signal is used for confirming that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated; or, the second signal includes information indicating that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated. The UE initiates a random access procedure based on the activated PRACH resource sets.

[0346] The second signal may also be construed as a confirmation signal, e.g., the second signal is used for confirming that the PRACH resource set to be activated by UE requesting and / or assisting is activated, i.e., the second signal corresponds to a piece of state information. After receiving the second signal transmitted by the base station, the UE thinks that the PRACH resource set to be activated by request and / or in an assisted manner is activated, and initiates the random access procedure based on the activated PRACH resource set. That is, the UE randomly selects a PRACH preamble on a PRACH time / frequency domain resource from the activated PRACH resource set to initiate the random access procedure.

[0347] Alternatively, the second signal may also be construed as activation signal for the PRACH resource sets, e.g., the second signal is used to indicate that one or more PRACH resource sets among the pre-configured PRACH resource sets are activated and corresponds to information of at least one bit. After receiving the second signal transmitted by the base station, the UE initiates the random access procedure based on the activated PRACH resource sets.

[0348] If there are a plurality of activated PRACH resource sets, the UE may randomly select a PRACH preamble on a PRACH time / frequency domain resource from the union of the plurality of activated PRACH resource sets to initiate the random access procedure; or the UE determines a PRACH resource set from the plurality of activated PRACH resource sets, then selects a PRACH preamble on a PRACH time / frequency domain resource from among the determined PRACH resource set to initiate the random access procedure.

[0349] In other words, the UE performs the following specific processes.

[0350] Step 1: the UE transmits a first signal to the base station, the first signal is used to request and / or assist to activate one of the plurality of pre-configured PRACH resource sets;

[0351] Step 2: the UE receives a second signal from the base station, the second signal is used to indicate information related to the activation of the PRACH resource sets; and

[0352] Step 3: during a preset activation period, the UE selects a PRACH preamble on a PRACH time / frequency domain resource from among the activated PRACH resource sets to initiate the random access procedure.

[0353] In an embodiment of the present disclosure, the random access procedure may be initiated based on a PRACH resource set during the activation period of the PRACH resource set. That is, the PRACH resource set to be activated by the first signal requesting and / or assisting or the PRACH resource sets to be activated by the indication of the second signal are only activated in a time period to be valid, and outside of the activation period, the PRACH resource sets are assumed to be deactivated.

[0354] Specifically, the activation period includes, but not limited to, at least one of the following:

[0355] (1) The activation period includes a time period with a preset length;

[0356] Outside of this time period, the PRACH resource set to be activated by the first signal requesting and / or assisting by is assumed to be deactivated; that is, the activation period is defined with a preset time duration. Optionally, the length of the activated time period is configured by the base station via the system information.

[0357] In one example, the system supports a procedure for activating the PRACH resources by requesting and / or assisting without the second signal (i.e., not including the above step 2), the starting position of the activation period is a position meeting a third preset interval after the first signal is transmitted, or the starting position of the activation period is a starting position of a first available RO meeting the third preset interval after the first signal is transmitted by the UE. In another example, the system supports presence of the second signal (i.e., including the above step 2), the starting position of the activation period is a position meeting a fourth preset interval after the second signal is received, or the starting position of the activation period is a starting position of a first available RO meeting the fourth preset interval after the second signal is received by the UE. The first available RO is the first available RO in the activated PRACH resource set.

[0358] (2) The activation period includes a first preset number of consecutive ROs.

[0359] After the first preset number of consecutive ROs, the PRACH resource set to be activated by the first signal requesting and / or assisting is assumed to be deactivated.

[0360] In one example, the system supports the procedure for activating the PRACH resources by requesting and / or assisting without the second signal (i.e., not including the above step 2), the first RO in the consecutive ROs is the first available RO meeting the third preset interval after the first signal is transmitted by the UE. In another example, the system supports presence of the second signal (i.e., including the above step 2), the first RO in the consecutive ROs is the first available RO meeting the fourth preset interval after the second signal is received by the UE.

[0361] (3) The activation period includes a preset maximum number of PRACH preamble transmission.

[0362] After the number of PRACH preamble transmission by the UE based on an activated PRACH resource set reaches the preset maximum number, the PRACH resource set is assumed to be deactivated. The activated PRACH resource set includes the PRACH resource set to be activated by the first signal requesting and / or assisting or the PRACH resource sets indicated to be activated by the indication of the second signal.

[0363] Optionally, the preset length of the time period included in the activation period is pre-configured by higher layer signal; or, the preset time duration of the activation period is indicated by the second signal; or, the first preset number of the consecutive ROs included in the activation period is pre-configured by higher layer signal; or, the first preset number of the consecutive ROs included in the activation period is indicated by the second signal; or, the preset maximum number of PRACH preamble transmission included in the activation period is pre-configured by higher layer signal; or, the preset maximum number of PRACH preamble transmission included in the activation period is indicated by the second signal.

[0364] In an embodiment of the present disclosure, the maximum number of PRACH preamble transmission by the UE based on an activated PRACH resource set is determined based on the duration of the activation period of the activated PRACH resource set. The allowable maximum number of PRACH preamble transmission on the activated PRACH resource set (i.e., the maximum number the random access procedure may be initiated) is determined by the UE according to the pre-configured duration of the activation period. For example, the allowable maximum number of PRACH preamble transmission is determined according to a pre-defined equation based on the duration. The pre-defined equation may be that the magnitude of the duration of the activation period is divided by a preset value and then rounded, and the preset value may be a value pre-defined by the base station.

[0365] In an embodiment of the present disclosure, prior to the step S101, the method further includes: receiving configuration information related to the first PRACH resource set and the second PRACH resource set, wherein the second PRACH resource set needs to be activated for use, and the second PRACH resource set may be activated by the first signal requesting and / or assisting, and / or may be activated by the indication of the second signal. The first PRACH resource set includes one or more PRACH resource sets, and the second PRACH resource set includes one or more PRACH resource sets.

[0366] That is, in an embodiment of the present disclosure, depending on whether the configured PRACH resources need to be activated or not, the configured PRACH resources are categorized into two categories: the first PRACH resource set (which may be one or more) may be used without being activated, i.e., it means that the first PRACH resource set takes effect once it is configured; and the second PRACH resource set (which may be one or more) need to be activated to be used, i.e., the second PRACH resource set being configured does not mean the second PRACH resource set taking effect. The first PRACH resource set may be referred to as a default PRACH resource set, a PRACH resource set which does not need to be activated, or a base PRACH resource set, and the second PRACH resource set may be referred to as a non-default PRACH resource set, a PRACH resource set which needs to be activated, or an additional PRACH resource set. In practical applications, the PRACH resources configured by the base station may include the PRACH resource sets of the above two categories, so as to achieve a better tradeoff between the reduction of the access latency and the efficient utilization of the PRACH resources.

[0367] In an embodiment of the present disclosure, the first PRACH resource set and the second PRACH resource set are associated with synchronization signal blocks (SSBs) respectively.

[0368] In an optional implementation, the first PRACH resource set is associated with a SSB based on a first parameter, and the second PRACH resource set is associated with a SSB based on a second parameter; wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is the number of SSBs being mapped to each RO and / or the number of contention-based PRACH preambles being mapped to each SSB, e.g., each of the first parameter and the second parameter is related to the higher layer parameter (ssb-perRACH-OccasionAndCB-PreamblesPerSSB). That is, each of the PRACH resource sets of the above two categories uses pre-configured different ssb-perRACH-OccasionAndCB-PreamblesPerSSBs. Optionally, the first parameter and the second parameter include the number of the ROs associated with one SSB and / or the number of the PRACH preambles associated with one SSB.

[0369] As an example, the ROs of the first PRACH resource set are sequentially associated with the SSB according to a pre-defined rule, and the ROs of the second PRACH resource set are sequentially associated with the SSB according to the same rule. For the associations between the PRACH resource sets of the above two categories and SSBs, the number of ROs associated with one SSB and / or the number of the PRACH preambles associated with one SSB are configured by the base station separately.

[0370] In another optional implementation, if the second PRACH resource set is not activated, the first PRACH resource set is associated with SSBs based on a third parameter; and if the second PRACH resource set is activated, the union of the first PRACH resource set and the second PRACH resource set is associated with SSBs based on the third parameter; wherein the third parameter is the number of SSBs being mapped to each random access occasion (RO), and / or the number of the contention-based PRACH preambles being mapped to each SSB. Similarly, the third parameter is related to the higher layer parameter, ssb-perRACH-OccasionAndCB-PreamblesPerSSB. The third parameter includes the number of the ROs associated with one SSB and / or the number of the PRACH preambles associated with one SSB.

[0371] As an example, if the second PRACH resource set is not activated, the ROs of the first PRACH resource set are sequentially associated with SSBs according to the pre-defined rule (the third parameter); if the second PRACH resource set is activated, all ROs of the first PRACH resource set and the second PRACH resource set are jointed to be sequentially associated with SSBs, irrespective of whether the second PRACH resource set is activated or not, the number of ROs associated with one SSB and / or the number of PRACH preambles associated with one SSB are constant.

[0372] In an embodiment of the present disclosure, one optional implementation is provided for the configurations of the first PRACH resource set and the second PRACH resource set. In particular, the first PRACH resource set is configured by a first radio resource control information unit, and the second PRACH resource set is configured by a second radio resource control information unit. That is, each of the first PRACH resource set (the default PRACH resources) and the second PRACH resource set (non-default PRACH resources) is separately configured with the PRACH resources by the base station. That is, the first PRACH resource set and the second PRACH resource set correspond to different PRACH configurations, respectively.

[0373] Optionally, the first radio resource control information unit and the second radio resource control information unit are configured by the system information. The system information includes at least two sets of PRACH configuration information, wherein the two sets of PRACH configurations correspond to the first PRACH resource set and the second PRACH resource set, respectively.

[0374] Alternatively, the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by the UE specific radio resource control (RRC) signal. For example, the first PRACH resource set corresponds to the cell-specific PRACH resources configured by the system information, i.e., the PRACH resources configured by information element (IE) PRACH-config-common, and the second PRACH resource set corresponds to the dedicated PRACH resources configured by the UE specific RRC signal, i.e., the PRACH resources configured by the IE PRACH-config-dedicated.

[0375] In an embodiment of the present disclosure, one another optional implementation is provided for the configurations of the first PRACH resource set and the second PRACH resource set. In particular, the first PRACH resource set and the second PRACH resource set are obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit. That is, the first PRACH resource set and the second PRACH resource set share the same PRACH configuration, and the first PRACH resource set and the second PRACH resource set are different subsets in a same PRACH resource pool. For example, the system information only includes a set of PRACH configuration information. The PRACH resource partition configuration is further performed on the PRACH resource pool corresponding to the set of PRACH configuration, i.e., by way of the partition, a portion of the PRACH resources serves as the second PRACH resource set, and the remaining PRACH resources serve as the first PRACH resource set.

[0376] In an embodiment of the present disclosure, the configuration information (approaches) of the first PRACH resource set and the second PRACH resource set may in particular include, but not limited to, at least one of the following:

[0377] (1) The first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning.

[0378] That is, the first PRACH resource set and the second PRACH resource set correspond to different configuration values of the same PRACH parameter, respectively. For example, there are a plurality of configuration values for a certain PRACH parameter, the PRACH resource sets corresponding to some of the configuration values are pre-defined or pre-configured as the second PRACH resource set, and the PRACH resource sets corresponding to the remaining configuration values are the first PRACH resource set. Alternatively, for each configuration value, the base station indicates whether the PRACH resources corresponding to the configuration value are the first PRACH resource set or the second PRACH resource set, respectively.

[0379] In an embodiment of the present disclosure, the first PRACH parameter and the second PRACH parameter include, but not limited to, at least one of the following parameters.

[0380] 1) a parameter related to (for indicating) a position of a time unit for a PRACH, e.g., the position of the time unit may refer to a slot position;

[0381] 2) a parameter related to (for indicating) a position of a frequency domain resource for a PRACH;

[0382] 3) a subcarrier spacing for a PRACH;

[0383] 4) an index of a PRACH configuration;

[0384] 5) a cyclic shift value of the PRACH preamble;

[0385] 6) a root sequence index of the PRACH preamble;

[0386] 7) a parameter related to transmission power of a PRACH;

[0387] 8) a threshold value or range for selecting the size of a Message 3 (Msg3) in the random access procedure for a PRACH resource set; and

[0388] 9) a threshold value or range for selecting reference signal receiving power (RSRP) of downlink pathloss reference for a PRACH resource set.

[0389] (2) The first PRACH resource set corresponds to the PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to the PRACH resources on a second uplink carrier.

[0390] That is, the second PRACH resource set and the first PRACH resource set correspond to the PRACH resources on different uplink carriers, respectively. For example, the system information includes configuration information for a plurality of uplink carriers and there is corresponding PRACH configuration information on each uplink carrier. The PRACH resource sets on some uplink carriers are pre-defined or pre-configured as the second PRACH resource set, and the PRACH resource sets on the remaining uplink carriers are the first PRACH resource set. Alternatively, for each uplink carrier, the base station indicates whether the PRACH resource set corresponding to the uplink carrier is the first PRACH resource set or the second PRACH resource set, respectively.

[0391] (3) The first PRACH resource set corresponds to the PRACH resources on a first initial uplink bandwidth part (BWP), and the second PRACH resource set corresponds to the PRACH resources on a second initial uplink BWP.

[0392] That is, the second PRACH resource set and the first PRACH resource set corresponds to the PRACH resources on different initial uplink BWPs, respectively. For example, the system information includes configuration information for a plurality of initial uplink BWPs and there is configuration information for corresponding PRACH on each initial uplink BWP. The PRACH resource sets on some initial uplink BWPs are pre-defined or pre-configured as the second PRACH resource set, and the PRACH resource sets on the remaining initial uplink BWPs are the first PRACH resource set. Alternatively, for each initial uplink BWP, the base station indicates whether the PRACH resources corresponding to the initial uplink BWP correspond to the first PRACH resource set or the second PRACH resource set, respectively.

[0393] (4) The first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format.

[0394] That is, the second PRACH resource set and the first PRACH resource set correspond to different PRACH formats, respectively. For example, the system information includes configuration information corresponding to a plurality of PRACH formats. The PRACH resource sets of some PRACH formats are pre-defined or pre-configured as the second PRACH resource set, and the PRACH resource sets of the remaining PRACH formats are the first PRACH resource set. Alternatively, for each PRACH format, the base station indicates that the PRACH format corresponds to the first PRACH resource set or the second PRACH resource set.

[0395] (5) The first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group.

[0396] That is, the second PRACH resource set and the first PRACH resource set correspond to different PRACH groups, respectively. Optionally, the different PRACH groups correspond to different PRACH preambles on the same RO. For example, the system information includes configuration information corresponding to a plurality of PRACH groups. The PRACH resource sets corresponding to some PRACH groups are pre-defined or pre-configured as the first PRACH resource set and the PRACH resource sets corresponding to the remaining PRACH groups are the first PRACH resource set. Alternatively, for each PRACH group, the base station indicates that the PRACH group corresponds to the first PRACH resource set or the second PRACH resource set, respectively.

[0397] (6) The second PRACH resource set corresponds to at least one PRACH resource set in a PRACH resource pool, and the first PRACH resource set corresponds to at least one PRACH resource set other than the at least one PRACH resource set in the same PRACH resource pool.

[0398] That is, the second PRACH resource set and the first PRACH resource set correspond to different PRACH resource sets in the same PRACH resource pool, respectively. For example, the system information includes configuration information for a plurality of PRACH resource sets. For example, a plurality of PRACH resource sets are configured by partitioning a PRACH resource pool and partition on the PRACH resource pool may be performed in the code domain (i.e., the PRACH preamble), the time domain and / or the frequency domain. The plurality of PRACH resource sets are different resource subsets in the same PRACH resource pool. Some of the PRACH resource sets are pre-defined or pre-configured as the second PRACH resource set, and the remaining PRACH resource sets are the first PRACH resource set. Alternatively, for each PRACH resource set, the base station indicates that the PRACH resource set corresponds to the first PRACH resource set or the second PRACH resource set, respectively.

[0399] As an example, the system information includes configuration information for a plurality of sets of PRACH preambles. The plurality of sets of PRACH preambles correspond to different resource subsets in the same PRACH resource pool. Some of the sets of the PRACH preambles are pre-defined or pre-configured as the second PRACH resource set, and the remaining sets of the PRACH preambles are the first PRACH resource set. Alternatively, for each set of PRACH preambles, the base station indicates that the set of PRACH preambles corresponds to the first PRACH resource set or the second PRACH resource set, respectively.

[0400] In an embodiment of the present disclosure, the first signal may be, but not limited to be, carried by at least one of the following physical signals or channels: an uplink physical signal (as newly defined), which is a different uplink physical signal from the existing PRACH, the physical uplink control channel (PUCCH), the sounding reference signal (SRS); the PRACH; and the PUCCH.

[0401] Specifically, depending on the information content carried by the first signal transmitted by the UE to the base station, the first signal is divided into the following three types.

[0402] The first type: the first signal carries no information other than the pre-configured PRACH resource sets to be activated by requesting and / or assisting. For example, the PRACH resource sets to be activated by the first signal requesting and / or assisting are known to both the UE and the base station, and no additional information is required for indication, thus the first signal may be carried by a piece of state information.

[0403] In one example, the first type of the first signal is carried by a pre-defined physical signal. In one cell, only one physical signal resource is configured to carry the first signal, i.e., all UEs that need to transmit the first signal in the cell use the same physical signal resource, and the PRACH resource set to be activated by these UEs requesting is the same one.

[0404] In another example, the first type of the first signal is carried by a PRACH. In one cell, only one PRACH preamble is configured to carry the first signal, i.e., all UEs that need to transmit the first signal in the cell use this PRACH preamble, and the PRACH resource set to be activated by these UEs requesting is the same one.

[0405] The second type: the first signal includes information related to the PRACH resource set to be activated by request. For example, the first signal is used for requesting a certain one of a plurality of pre-configured PRACH resource sets, i.e., the first signal is carried by information of at least one bit.

[0406] Specifically, the first signal carries (in an explicit manner or an implicit manner) first information about the PRACH resource set to be activated by request, and the first information included in the first signal may include, but not be limited to, at least one of the following information.

[0407] (1) Information related to a PRACH configuration corresponding to the PRACH resource set to be activated by request.

[0408] That is, the first signal requests to activate a PRACH resource set corresponding to a certain PRACH configuration. For example, the system information includes a plurality of PRACH configuration information. The first signal may indicate that the PRACH resource corresponding to one PRACH configuration is to be activated, e.g., the first signal indicates the index of the PRACH configuration.

[0409] (2) Information related to a PRACH parameter corresponding to the PRACH resource set to be activated by request.

[0410] That is, the first signal requests to activate the PRACH resources corresponding to a certain PRACH parameter value. For example, the system information includes information for a plurality of configuration values of a PRACH parameter. The first signal may indicate that the PRACH resource corresponding to one configuration parameter value is to be activated, e.g., the first signal indicates the index of the PRACH parameter value.

[0411] (3) Information related to an uplink carrier corresponding to the PRACH resource set to be activated by request.

[0412] That is, the first signal requests to activate the PRACH resources on a certain uplink carrier. For example, the system information includes configuration information for a plurality of uplink carriers, and there is configuration information for corresponding PRACH on each uplink carrier. The first signal may indicate that the PRACH resource on an uplink carrier is to be activated, e.g., the first signal indicates the index of the uplink carrier.

[0413] (4) Information related to an initial uplink BWP corresponding to the PRACH resource set to be activated by request.

[0414] That is, the first signal requests to activate the PRACH resources on a certain initial uplink BWP. For example, the system information includes configuration information for a plurality of initial uplink BWPs, and there is corresponding PRACH configuration on each initial uplink BWP. The first signal may indicate that the PRACH resource on an initial uplink BWP is to be activated, e.g., the first signal indicates the index of the initial uplink BWP.

[0415] (5) Information related to a PRACH group corresponding to the PRACH resource set to be activated by request.

[0416] That is, the first signal requests to activate the PRACH resources corresponding to a certain PRACH group. For example, the system information includes information of a plurality of PRACH groups, and the first signal indicates that the PRACH resource corresponding to the PRACH group A or the PRACH group B is to be activated.

[0417] (6) Information related to a PRACH format corresponding to the PRACH resource set to be activated by request.

[0418] That is, the first signal requests to activate the PRACH resources corresponding to a certain PRACH format. For example, the system information includes information of a plurality of PRACH formats, and the first signal indicates that the PRACH resource corresponding to the PRACH format 1 or the PRACH format 2 is to be activated.

[0419] (7) Information related to the PRACH resource set to be activated by request.

[0420] That is, the first signal requests to activate the PRACH resources corresponding to a certain PRACH resource set. For example, the system information includes configurations for a plurality of PRACH resource sets, and the first signal indicates that one of the PRACH resource sets is to be activated, e.g., the first signal indicates the index of the PRACH resource set.

[0421] As an example, the first signal requests to activate the PRACH resources corresponding to a certain set of PRACH preambles. For example, the system information includes configuration information for a plurality of sets of PRACH preambles, and the first signal indicate that the PRACH resource corresponding to one of the sets of PRACH preambles is to be activated, e.g., the first signal indicates the index of a set of PRACH preambles.

[0422] The third type: the first signal includes assistance information of UE, and the assistance information may be use for assisting the base station in activation or deactivation of one or more pre-configured PRACH resource sets, i.e., the first signal is carried by information of at least one bit.

[0423] The first signal carries (in an implicit manner or an explicit manner) second information for assisting the base station in activation of the PRACH resource set, and the second information may also be construed as the assistance information. After receiving the second information reported by the UE, the base station determines whether one or more PRACH resource sets are to be activated or not. The second information included in the first signal may include, but not be limited to, at least one of the following information.

[0424] (1) a type of a UE;

[0425] (2) a size of the Msg3;

[0426] (3) a RSRP value of a downlink pathloss reference;

[0427] (4) a priority of arriving data;

[0428] (5) a type of the arriving data;

[0429] (6) an index of a logical channel (LCH) or a logical channel group (LCH group) where the arriving data is located;

[0430] (7) a size of the amount of the arriving data;

[0431] (8) remaining packet delay budget (PDB) of the arriving data; and

[0432] (9) an event for triggering the random access procedure.

[0433] In an embodiment of the present disclosure, the event for triggering the random access procedure may be one of the following events.

[0434] 1) an initial access procedure initiated from the RRC idle status (RRC_IDLE);

[0435] 2) a RRC connection reestablishment procedure;

[0436] 3) during the RRC connected status (RRC_CONNECTED) or during the RRC inactive status (RRC_INACTIVE), while the small data transmission (SDT) is in progress, when the uplink synchronization status is non-synchronization, there is uplink or downlink data arriving;

[0437] 4) during the RRC connected status or during the RRC inactive status, while the SDT procedure is in progress, when there is no PUCCH resource for the scheduling request (SR), there is uplink data arriving;

[0438] 5) handover, except the case in which no RACH handover is configured (RACH-less);

[0439] 6) SR failure;

[0440] 7) an explicit request re-configured by the RRC in synchronization;

[0441] 8) a RRC connection resumption procedure initiated from the RRC inactive status;

[0442] 9) time alignment is established for a main timing advance group (TAG) or a secondary TAG;

[0443] 10) requesting other system information;

[0444] 11) beam failure recovery procedure;

[0445] 12) the continuous uplink listen before talk (LBT) failure on a special cell (SpCell);

[0446] 13) a small data transmission in RRC inactive status;

[0447] 14) a random access procedure for the purpose of positioning during the RRC connected status;

[0448] 15) the earlier uplink synchronization on a candidate cell managed by mobility triggered by the layer 1 / layer 2 (L1 / L2 Triggered Mobility, LTM); and

[0449] 16) the RACH-based LTM cell handover.

[0450] In an embodiment of the present disclosure, the remaining PDB may also be referred to as the remaining time, which is mainly for the case in which there are delay requirements for the arriving data of the UE. Once the required latency cannot be met, it is not necessary to transmit the arriving data packet, and the data packet may be dropped by the UE. The remaining time or the remaining PDB for the arriving data is defined as the remaining time from the discarding moment.

[0451] In one example, the second type and the third type of the first signal may be carried by a physical signal in an implicit manner. For example, a plurality of physical signal resources are configured by the base station to carry the first signal. Code-division multiplexing, time-division multiplexing and / or frequency-division multiplexing are possible between a plurality of different physical signal resources. Different physical signal resources may be used to request to activate different PRACH resource sets, or to report the assistance information.

[0452] In another example, the second type and the third type of the first signal may also be carried by a PRACH in an implicit manner. For example, a plurality of PRACH resources (e.g., a plurality of PRACH preambles) are configured by the base station to be specifically used to request activation of different PRACH resource sets, or to report the assistance information. The plurality of PRACH preambles cannot be used for the random access.

[0453] In yet another example, the second type and the third type of the first signal may be carried by a PUCCH in an explicit manner. That is, the PUCCH is used to indicate a request for activation of different PRACH resource sets, or to report the assistance information.

[0454] In an embodiment of the present disclosure, the second signal may be, but not limited to be, carried by at least one of the following physical signals or channels: a downlink physical signal (as newly defined), which is a different physical signal from the existing primary synchronization signal (PSS), the secondary synchronization signal (SSS), and the channel state information-reference signal (CSI-RS); the physical broadcast channel (PBCH), the physical downlink control channel (PDCCH); and the medium access control (MAC) layer signal.

[0455] Specifically, depending on the information content carried by the second signal received by the UE from the base station, the second signal is divided into the following two types.

[0456] The first type: the second signal is merely used for confirming that the PRACH resources to be activated by UE requesting and / or assisting are activated, and carries no other information. That is, the second signal may be carried by a piece of state information or information of one bit. In one example, the second signal is carried by a physical signal; and in another example, the second signal is indicated by a piece of state information or information of one bit in the PBCH or the PDCCH.

[0457] The second type: the second signal is used to indicate that one or more pre-configured PRACH resource sets are activated, or whether one or more pre-configured PRACH resource sets are activated or not, i.e., the second signal is carried by information of at least one bit. In one example, the second signal is carried by the PBCH, PDCCH and MAC layer signal.

[0458] Optionally, the PDCCH for carrying the second signal may include, but not be limited to, at least one of the following.

[0459] (1) A PDCCH scrambled with a dedicated preset radio network temporary identity (RNTI).

[0460] That is, the second signal may be indicated by the PDCCH scrambled with the dedicated RNTI. The dedicated RNTI may be a pre-defined or pre-configured RNTI value to transmit the second signal. The DCI carried by the PDCCH may adopt the original DCI format or a newly defined DCI format.

[0461] (2) A PDCCH used for scheduling a random access response physical downlink shared channel (PDSCH), i.e., the PDCCH scrambled with a random access radio network temporary identity (RA-RNTI).

[0462] That is, the second signal may be indicated by the PDCCH scrambled with the RA-RNTI, e.g., indicated by the scheduling PDCCH for the random access response (RAR), e.g., indicated by a reserved bit or a reserved status value in the scheduling PDCCH for the RAR.

[0463] (3) A PDCCH used for scheduling the system information PDSCH, i.e., the PDCCH scrambled with the system information radio network temporary identity (System Information-RNTI).

[0464] That is, the second signal may be indicated by the PDCCH scrambled with the SI-RNTI, e.g., indicated by the scheduling PDCCH for the system information, e.g., indicated by a reserved bit or a reserved status value in the scheduling PDCCH for the system information.

[0465] (4) A PDCCH used for scheduling the paging message PDSCH, i.e., the PDCCH scrambled with the paging radio network temporary identity (Paging-RNTI, P-RNTI).

[0466] That is, the second signal may be indicated by the PDCCH scrambled with the P-RNTI, e.g., indicated by the scheduling PDCCH for the paging message, e.g., indicated by a reserved bit or a reserved status value in the scheduling PDCCH for the paging message.

[0467] Optionally, the MAC layer signal for carrying the second signal may include, but not be limited to, at least one of the following.

[0468] (1) A MAC subheader included in a MAC protocol data unit (PDU) for carrying the RAR.

[0469] That is, the second signal is carried by adding a dedicated MAC subheader in the RAR PDU. For example, a MAC subheader is newly defined to indicate the second signal, and the MAC subheader is included in the RAR PDU, i.e., carried by the RAR PDSCH.

[0470] (2) MAC RAR.

[0471] That is, the second signal is indicated by the MAC RAR. For example, a pre-defined or pre-configured PRACH preamble is used to request activation of the PRACH resources, and the RAR corresponding to the PRACH preamble is used to carry the second signal, e.g., the second signal is carried by re-defining the information content in the existing RAR.

[0472] In an embodiment of the present disclosure, the information for indicating that the PRACH resource sets by the first signal requesting and / or assisting are activated or whether the PRACH resource sets are activated or not included in the second signal, or the information for indicating that the one or more PRACH resource sets are activated, or whether the one or more PRACH resource sets are activated or not included in the second signal, may specifically include, but is not limited to, at least one of the following information.

[0473] (1) Information related to the PRACH configurations corresponding to one or more activated PRACH resource sets, respectively.

[0474] That is, the second signal is used to indicate information that PRACH resource sets corresponding to one or more PRACH configurations are activated. For example, the second signal indicates the indexes of one or more PRACH configurations, wherein each PRACH configuration corresponds to an IE for configuring the PRACH resource, and each PRACH configuration is configured with or associated with a corresponding index.

[0475] (2) Information related to the PRACH parameter values corresponding to one or more activated PRACH resource sets, respectively.

[0476] That is, the second signal is used to indicate information that the PRACH resource sets corresponding to one or more PRACH parameter values are activated. For example, the second signal indicates one or more pre-configured values of a certain PRACH parameter.

[0477] (3) Information related to uplink carriers corresponding to one or more activated PRACH resource sets, respectively.

[0478] That is, the second signal is used to indicate information that the PRACH resource sets on one or more uplink carriers are activated. For example, the second signal indicates the indexes of one or more uplink carriers, wherein each uplink carrier is configured with or associated with a corresponding index.

[0479] (4) Information related to initial uplink BWPs corresponding to one or more activated PRACH resource sets, respectively.

[0480] That is, the second signal is used to indicate information that the PRACH resource sets on one or more initial uplink BWPs are activated. For example, the second signal indicates the indexes of one or more initial uplink BWPs, wherein each initial uplink BWP is configured with or associated with a corresponding index.

[0481] (5) Information related to the PRACH groups corresponding to one or more activated PRACH resource sets, respectively.

[0482] That is, the second signal is used to indicate information that the PRACH resource sets corresponding to one or more PRACH groups are activated. For example, the second signal indicates one or more PRACH groups.

[0483] (6) Information related to PRACH formats corresponding to one or more activated PRACH resource sets, respectively.

[0484] That is, the second signal is used to indicate information that the PRACH resource sets corresponding to one or more PRACH formats are activated. For example, the second signal indicates one or more PRACH formats.

[0485] (7) Indexes of one or more activated PRACH resource sets.

[0486] That is, the second signal is used to indicate information that one or more pre-configured PRACH resource sets are activated. For example, the second signal indicates the indexes of the PRACH resource sets, wherein each PRACH resource set is configured with or associated with a corresponding index.

[0487] As an example, the second signal is used to indicate information that the PRACH resource sets corresponding to one or more sets of PRACH preambles are activated. For example, the second signal indicates the index of a set of PRACH preambles, wherein each set of PRACH preambles is configured with or associated with a corresponding index.

[0488] (8) Bitmap information for indicating whether a plurality of PRACH resource sets are activated or not, respectively.

[0489] That is, the second signal indicates information about whether one or more PRACH resource sets are activated or not through the bitmap information respectively, and each information bit in the bitmap corresponds to a pre-configured PRACH resource set.

[0490] In an embodiment of the present disclosure, there is a certain timing relationship between the first signal transmitted by the UE to the base station and the second signal received by the UE from the base station.

[0491] In an optional implementation, after transmitting the first signal, the UE monitors the second signal at a first position meeting a first preset interval, or within a first time window (the first time window including transmission opportunities for a plurality of second signal) from the first position, or the first transmission opportunity for the second signal after the first position. In this timing relationship, the first signal and the second signal have a one-to-one correspondence relationship as shown in FIG. 5.

[0492] In another optional implementation, the UE determines a second time window where the first signal is located, wherein the second time window includes a plurality of transmission opportunities for the first signal; after an ending position of the second time window, the UE monitors the second signal at a second position meeting a second preset interval, or within a first time window (the first time window including a plurality of transmission opportunities for the second signal) from the second position, or on a first transmission opportunity for the second signal after the second position. In this timing relationship, the first signal and the second signal have a multiple-to-one correspondence relationship as shown in FIG. 6.

[0493] In an embodiment of the present disclosure, UE' s behavior after monitoring the second signal is pre-defined, e.g., it may be one of the following schemes.

[0494] In an optional implementation, if the UE has not monitored the second signal, or if the UE has monitored the second signal and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated, the UE performs, but is not limited to, at least one of the following behaviors.

[0495] (1) Initiating the random access procedure based on the pre-configured first PRACH resource set.

[0496] For example, the UE selects a PRACH preamble on a PRACH time / frequency domain resource from the first PRACH resource set to initiate the random access procedure.

[0497] (2) Continuing to attempt to transmit the first signal on a next transmission opportunity for the first signal, and reporting error information to a higher layer, if the second signal has not been monitored yet after a maximum number of attempts is reached, or the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated; and

[0498] Optionally, the physical layer of the UE reports the error information to the higher layer.

[0499] (3) Continuing to attempt to transmit the first signal on a next transmission opportunity for the first signal, and initiating the random access procedure based on the pre-configured first PRACH resource set, if the second signal has not been monitored yet after a maximum number of attempts is reached, or the second signal has been monitored and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated.

[0500] For example, the UE selects a PRACH preamble on a PRACH time / frequency domain resource from the first PRACH resource set to initiate the random access procedure.

[0501] In another optional implementation, if the UE has monitored the second signal, and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or indicates that one or more PRACH resource sets are activated, the UE performs, but is not limited to, at least one of the following behaviors.

[0502] (1) Initiating the random access procedure based on the activated PRACH resource set.

[0503] For example, the UE selects a PRACH preamble on a PRACH time / frequency domain resource from the activated PRACH resource set to initiate the random access procedure.

[0504] (2) Initiating the random access procedure based on the union of the first PRACH resource set and the activated PRACH resource set.

[0505] For example, the UE selects a PRACH preamble on a PRACH time / frequency domain resource from the union of the first PRACH resource set and the activated PRACH resource set to initiate the random access procedure.

[0506] In an embodiment of the present disclosure, in case where the random access procedure is initiated based on the union of the first PRACH resource set and the activated PRACH resource set, the probabilities which the first PRACH resource set and the activated PRACH resource set are selected are configured separately. In one example, the probability the UE selects the first PRACH resource set to initiate the random access procedure is the same as the probability the UE selects the activated PRACH resource set to initiate the random access procedure, i.e., both the probabilities are 0.5. In another example, the probability the UE selects the activated PRACH resource set to initiate the random access procedure is different from the probability the UE selects the first PRACH resource set to initiate the random access procedure. That is, the activated PRACH resource set and the first PRACH resource set may correspond to different weighting coefficients, e.g. the probabilities of the two may correspond to 0.7 and 0.3 based on the pre-configured weighting coefficients.

[0507] In yet another optional implementation, if the second signal has not been monitored, or if the second signal has been monitored, and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is not activated, then the random access procedure is initiated based on a default PRACH resource set; that is, the UE assumes that a third PRACH resource set is activated, and initiates the random access procedure based on the third PRACH resource set. If the second signal has been monitored, and the second signal indicates that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, then the UE thinks that the second PRACH resource set is activated and initiates the random access procedure based on the activated PRACH resource set; wherein the default PRACH resource set is a subset of the activated PRACH resource set.

[0508] In an embodiment of the present disclosure, the system supports the procedure for activating PRACH resources by request with the second signal (i.e., including the above step 2) and without the second signal (i.e., not including the above step 2), and the procedure for the assistance activation may be conceived analogously and will not be repeated here. In other words, the activation of a part of the PRACH resource sets by request requires the confirmation from the network, and the activation of another part of the PRACH resource sets by request requires no confirmation from the network. The activation of which of the PRACH resource sets by request requiring the confirmation from the network may be determined by the following ways.

[0509] (1) Whether the activation of a PRACH resource set by request requiring the confirmation from the network or not is configured by the base station. For example, assuming that the activation of the PRACH resources by request requiring the confirmation from the network is Mode 1, and the activation of the PRACH resources by request requiring confirmation from the network is Mode 2. For each PRACH resource set, the base station may configure the mode 1 for activation by request or the mode 2 for activation by request, respectively. Each of the PRACH resource sets corresponds to a PRACH configuration, an uplink carrier, an initial uplink BWP, a PRACH group, a PRACH format and a PRACH preamble set, respectively.

[0510] (2) Whether the PRACH resource set being requested to be activated requires the confirmation from the network is indicated by the UE through the first signal, e.g., indicated implicitly through the first signal. The first signal requiring the confirmation from the network and the first signal requiring no confirmation from the network may use physical signals corresponding to different codewords or physical signals on different time / frequency domain resources. For example, depending on at least one of the factors such as the type of the UE, the size of the Msg3, the estimation value of the RSRP value of the downlink pathloss reference, the amount of the arriving uplink data, the priority of the arriving uplink data, the remaining PDB of the arriving uplink data, and an event for triggering the random access procedure, the UE determines to activate which of the PRACH resource sets, and whether the confirmation from the network is required.

[0511] In an embodiment of the present disclosure, if the random access is not successful after the activation period, the random access procedure is initiated based on the first PRACH resource set. For example, if the random access has not been successful when a number of transmissions of the PRACH preambles based on the PRACH resource set activated by the first signal requesting and / or assisting reaches a maximum preset number, the random access procedure is initiated based on the first PRACH resource set. For another example, the UE initiates the random access procedure on the first PRACH resource set, if the contention-based access is not successful when the number of times the UE initiates the random access procedure on the activated PRACH resource set reaches an allowable maximum number of times (i.e., reaching the maximum number of times pre-configured by the base station or the maximum number of times as calculated), i.e., when the number of times the UE transmits the PRACH preamble on the activated PRACH resource set reaches the maximum number. Optionally, the UE initiates the random access procedure on the PRACH resources (corresponding to the first PRACH resource set) corresponding to the default PRACH configuration, or the UE initiates the random access procedure on the PRACH resources (corresponding to the first PRACH resource set) on the default uplink carrier, or the UE initiates the random access procedure on the PRACH resources (corresponding to the first PRACH resource set) on the default initial uplink BWP, or the UE initiates the random access procedure on the PRACH resources (corresponding to the first PRACH resource set) corresponding to the default PRACH format, or the UE initiates the random access procedure on the default PRACH group (corresponding to the first PRACH resource set), or the UE initiates the random access procedure on the default PRACH resource set (corresponding to the first PRACH resource set).

[0512] In an embodiment of the present disclosure, in case where the first signal is carried by the PRACH, the base station configures the PRACH for function of requesting the activation of the PRACH resources and the PRACH for function of random access with corresponding PRACH resources, respectively. For example, the system information includes two PRACH configurations, wherein the PRACH resources corresponding to the first PRACH configuration are for the purpose of random access, and the PRACH resources corresponding to the second PRACH configuration are for the purpose of requesting the activation of other PRACH resources. For example, the PRACH resource corresponding to the second PRACH configuration is used for requesting activation of all or part of the PRACH resource corresponding to the first PRACH configuration.

[0513] In an optional implementation, the PRACH resources for carrying the first signal and the PRACH resources for initiating the random access procedure are configured by different radio resource control information units, respectively.

[0514] In another optional implementation, the PRACH resources for carrying the first signal and the PRACH resources for initiating the random access procedure are obtained by division of the PRACH resource pool. For example, the PRACH for carrying the first signal and the PRACH for initiating the random access correspond to different ROs. Optionally, the PRACH for function of requesting the activation of the PRACH resources and the PRACH for function of random access correspond to different PRACH resource subsets in the same PRACH pool. For example, within the PRACH resource pool for function of random access, a portion of the PRACH resources is indicated to request the activation of other PRACH resources rather than the portion of the PRACH resources. Partition on the PRACH resource pool may be performed in the code domain, the time domain and / or the frequency domain to configure the PRACH resource subsets. That is, the PRACH for function of requesting the activation of the PRACH resources and the PRACH for function of random access correspond to the PRACH resources on different ROs in the same PRACH resource pool, or different PRACH preambles on different ROs.

[0515] For another example, the PRACH for carrying the first signal and the PRACH for initiating the random access correspond to different PRACH preambles on the same RO. That is, the PRACH for function of requesting the activation of the PRACH resources and the PRACH for function of random access use different PRACH preambles and share the same RO. For example, the PRACH for function of random access uses 64 PRACH preambles, and the PRACH for requesting the activation of the other PRACH resources uses the other PRACH preambles rather than the 64 PRACH preambles. For example, the first 64 PRACH preambles determined based on the root sequence index of the PRACH preamble and a cyclic shift value of the PRACH preamble are used for function of the random access, and the determined 65th PRACH preamble is used to request activation of other PRACH resources.

[0516] In still another optional implementation, the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources. For example, the PRACH for carrying the first signal and the PRACH for initiating the random access share the same PRACH preamble of the same RO. Optionally, in case that the PRACH resources for carrying the first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources, the shared PRACH resources belong to the first PRACH resource set. The UE initiates the random access procedure based on the shared PRACH resources and if the random access is not successful, the UE initiates the random access procedure based on the PRACH resource set which is activated based on the shared PRACH resources by request.

[0517] Optionally, after initiating the random access procedure based on the shared PRACH resources, the UE receives the Message 2 (Msg2) in the random access procedure, wherein the Message 2 including information indicating that the PRACH resource set is activated; and if the random access procedure is not successful, the UE initiates the random access procedure based on the activated PRACH resource set indicated by the Message 2.

[0518] As an example, the UE firstly initiates the random access procedure based on the first PRACH resource set. During the initiated random access procedure, the Msg2 received by the UE may include information indicating whether the second PRACH resource set is activated or not (indicating through the PDCCH of Msg2 or the MAC subheader in the RAR PDU). If the Msg2 (e.g., the MAC subheader) indicates the second PRACH resource set is activated and the contention of the random access procedure is not successful, the UE randomly selects a PRACH preamble on a PRACH time / frequency domain resource from the activated second PRACH resource set to initiate the random access procedure; or, the UE randomly selects a PRACH preamble on a PRACH time / frequency domain resource from the total set of the activated second PRACH resource set and the first PRACH resource set to initiate the random access procedure.

[0519] In an embodiment of the present disclosure, the random access being not successful may be but not limited to at least one of the following cases.

[0520] (1) The UE has not monitored the RAR corresponding to the PRACH preamble the UE transmits on the first PRACH resource set in the Msg2 of the random access procedure.

[0521] (2) The UE has not monitored the Msg4 of the random access procedure, or, the UE has monitored the Msg4 of the random access procedure.

[0522] (3) The contention is not successful in the random access procedure and the number of the random access procedure has reached the allowed maximum number (the PRACH preamble transmission reached the maximum number).

[0523] In an embodiment of the present disclosure, for a UE of a preset type and / or a UE supporting a preset capability, the UE cannot use the first PRACH resource set to initiate the random access procedure, and may only prioritize the use of the second PRACH resource set to initiate the random access procedure, and thus the UE needs to transmit the first signal to request the activation of the second PRACH resource set. For other UEs, the UEs may directly use the first PRACH resource set to initiate the random access procedure. For example, the UE of the preset type may be an internet of thing (IoT) UE, and the UE with the preset capability may be a UE supporting the capability of transmitting the first signal.

[0524] In an optional implementation, the UE is triggered to transmit the first signal when at least one of the following conditions is met:

[0525] (1) a request or an indication from a higher layer is received, wherein the request or the indication is about transmitting the first signal or initiating the random access procedure;

[0526] (2) the random access procedure is initiated;

[0527] (3) the size of a Message 3 (Msg3) in the random access procedure is greater than or equal to a first preset threshold value; optionally, the first preset threshold value is configured by the base station;

[0528] (4) the size of a Message 3 in the random access procedure is within a first preset range; optionally, the first preset range is configured by the base station;

[0529] (5) the RSRP value of the downlink pathloss reference is less than a second preset threshold value; optionally, the second preset threshold value is configured by the base station;

[0530] (6) the RSRP value of the downlink pathloss reference is within a second preset range; optionally, the second preset range is configured by the base station;

[0531] (7) the event for triggering the random access procedure is a preset event, and the preset event may be at least one of the events for triggering the random access procedure as described above; for example, the preset event may be a small data transmission, that is, the UE directly transmits the arriving data to the base station through the random access procedure without establishing the RRC connected status;

[0532] (8) the priority of the arriving data is lower than a preset priority, i.e., the value of the priority is greater or equal to the value of the preset priority, the smaller the value of priority, the higher the corresponding priority; optionally, the preset priority is configured by the base station;

[0533] (9) the type of the arriving data is of a preset type; for example, the preset type is control plane (CP) data or user plane (UP) data;

[0534] (10) the index of a logical channel where the arriving data is located or the index of a logical channel group where the arriving data is located is a preset index;

[0535] (11) the size of the amount of the arriving data amount is greater than or equal to a third preset threshold value; optionally, the third preset threshold value is configured by the base station;

[0536] (12) the remaining packet delay budget of the arriving data is greater than or equal to a fourth preset threshold value; optionally, the fourth preset threshold value is configured by the base station, i.e., there are delay requirements for the arriving data by the UE; once a predetermined delay is exceeded, there is no need for transmission, and UE may drop this data packet; and

[0537] (13) the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches the second preset number; optionally, the second preset number is configured by the base station.

[0538] In practical application, the condition for triggering the UE to transmit the first signal to the base station may be pre-configured by the base station. For example, the base station may configure which of the PRACH resources are the second PRACH resource set, i.e., these PRACH resources need to be activated for use. In addition, the base station may also configure the condition for triggering the UE to transmit, to the base station, the first signal to activate these PRACH resources, e.g., the condition is configured as one or more of the above conditions.

[0539] Optionally, the condition for triggering the UE to transmit the first signal is configured by the system information, or configured by the UE specific RRC signal.

[0540] According to the solutions provided by an embodiment of the present disclosure, it may be guaranteed that the number of activated PRACH resources is matched to the real-time load on the network, thereby avoiding the waste of the PRACH resources and achieving efficient utilization of the PRACH resources.

[0541] In an embodiment of the present disclosure, there is provided another method performed by a UE in the communication system, as shown in FIG. 7, the method includes：

[0542] Step S201: receiving a third signal, the third signal including information related to activation or deactivation of the PRACH resource set; and

[0543] Step S202: during an activation period of the PRACH resource set, initiating the random access procedure based on the activated PRACH resource set.

[0544] Similarly, in order to utilize the PRACH resources efficiently, the PRACH resources configured by the base station (i.e., the network) need to be activated for use, including but not limited to the cell-specific PRACH resources configured by the system information and / or the dedicated PRACH resources configured by the UE specific signal, etc. That is, the configuring the PRACH resources does not mean that the PRACH resources are valid, and the PRACH resources need to be further activated to be valid. If the configured PRACH resources are not activated, these configured PRACH resources cannot be used by the UE.

[0545] However, in the embodiment of the present disclosure, as compared with the on-demand PRACH approach as described above, the UE does not need to transmit an activation requesting signal (i.e., the first signal), the base station perceives the real-time load on the network by itself, and the base station decides whether to activate the second PRACH resource set or not according to the perceived real-time load on the network, and transmits the signal (the third signal) for activation / deactivation of the second PRACH resource set periodically or dynamically. Correspondingly, the UE receives the third signal for activation / deactivation of the second PRACH resource set from the base station, and initiates the random access procedure on the activated PRACH resource set, so as to achieve the purpose of efficient use of PRACH resources.

[0546] The PRACH resource set refers to a set including a group of PRACH resources, which may also be referred to as a PRACH resource collection. With respect to the PRACH resource pool, a PRACH resource set may also be referred to as a PRACH resource subpool or a PRACH resource subset. A PRACH resource set may be a part of PRACH resources in a PRACH resource pool. For example, a plurality of PRACH resource sets are configured by partitioning a large PRACH resource pool. A PRACH resource pool refers to a large pool or set of the PRACH resources corresponding to all PRACH preambles on all PRACH frequency domain resources on all PRACH time slots as determined by configuration parameters. For example, partition on the PRACH resource pool may be performed in the code domain (i.e., the PRACH preamble), the time domain and / or the frequency domain. In this case, a PRACH resource set may also be referred to as a PRACH resource subset, or a PRACH resource partition.

[0547] Optionally, the PRACH resource set includes but not limited to at least one of the following:

[0548] (1) a set of a part of ROs in the PRACH resource pool, i.e., a set of PRACH resources on a group of ROs;

[0549] (2) a set of a part of PRACH time units in the PRACH resource pool, for example, the time unit may refer specifically to the time domain, i.e., a set of PRACH resources on a group of PRACH time slot;

[0550] (3) a set of a part of PRACH frequency domain resources in the PRACH resource pool, i.e., a set of PRACH resources on a group of PRACH frequency domain resources;

[0551] (4) a set of a part of PRACH preambles in the PRACH resource pool, i.e., a set of PRACH resources corresponding to a group of PRACH preambles; and

[0552] (5) a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool, i.e., a set of PRACH resources correspond to a part of PRACH preambles on a group of ROs.

[0553] In an embodiment of the present disclosure, during the activation period of the PRACH resource set, the random access procedure is initiated based on the PRACH resource set which is indicated to be activated. That is, there is a limitation on the activation period for the PRACH resource set which is indicated to be activated, i.e., the PRACH resource set which is indicated to be activated is only activated (i.e., available) within the activation period and is deactivated (i.e., unavailable) outside of the activation period.

[0554] The activation period includes, but not limited to, at least one of the following:

[0555] (1) The activation period includes a time period with a preset length;

[0556] (2) The activation period includes a first preset number of consecutive ROs.

[0557] (3) The activation period includes a preset maximum number of PRACH preamble transmission.

[0558] Optionally, the preset length of the time period included in the activation period is pre-configured by higher layer signal; or, the preset length of the time period included in the activation period is indicated by the third signal; or, the first preset number of the consecutive ROs included in the activation period is pre-configured by higher layer signal; or, the first preset number of the consecutive ROs included in the activation period is indicated by the third signal; or, the preset maximum number of PRACH preamble transmission included in the activation period is pre-configured by higher layer signal; or, the preset maximum number of PRACH preamble transmission included in the activation period is indicated by the third signal.

[0559] For a more detailed description of the activation period, please see the above description of the method performed by the UE (i.e., the on-demand PRACH approach), which will not be repeated here.

[0560] In an embodiment of the present disclosure, prior to the step S201, the method further includes: receiving configuration information related to the first PRACH resource set and the second PRACH resource set, wherein the second PRACH resource set needs to be activated for use, the second PRACH resource set may be indicated by the third signal to be activated or deactivated. The first PRACH resource set includes one or more PRACH resource sets, and the second PRACH resource set includes one or more PRACH resource sets.

[0561] As mentioned above, the PRACH resources configured by the base station are of two categories, the first PRACH resource set may be used without being activated, and the second PRACH resource set needs to be activated for use. In an embodiment of the present disclosure, the PRACH resources used for activation / deactivation may correspond to the second PRACH resource set.

[0562] In an embodiment of the present disclosure, the first PRACH resource set is associated with synchronization signal blocks (SSBs) based on a first parameter; the second PRACH resource set is associated with SSBs based on a second parameter; wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is the number of SSBs being mapped to each RO and / or the number of contention-based PRACH preambles being mapped to each SSB.

[0563] In an embodiment of the present disclosure, if the second PRACH resource set is not activated, the first PRACH resource set is associated with SSBs based on a third parameter; and if the second PRACH resource set is activated, the union of the first PRACH resource set and the second PRACH resource set is associated with the SSBs based on the third parameter; wherein the third parameter is the number of SSBs being mapped to each random access occasion (RO), and / or the number of the contention-based PRACH preambles being mapped to each SSB.

[0564] In an embodiment of the present disclosure, the first PRACH resource set is configured by a first radio resource control information unit, and the second PRACH resource set is configured by a second radio resource control information unit; wherein the first radio resource control information unit and the second radio resource control information unit are configured by the system information; or the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by UE specific radio resource control (RRC) signal.

[0565] In an embodiment of the present disclosure, the first PRACH resource set and the second PRACH resource set are obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit.

[0566] In an embodiment of the present disclosure, configuration information for the first PRACH resource set and the second PRACH resource set includes at least one of the following:

[0567] the first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning;

[0568] the first PRACH resource set corresponds to the PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to the PRACH resources on a second uplink carrier;

[0569] the first PRACH resource set corresponds to the PRACH resources on a first initial uplink bandwidth part (BWP), and the second PRACH resource set corresponds to the PRACH resources on a second initial uplink BWP;

[0570] the first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format;

[0571] the first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group; and

[0572] wherein the first PRACH parameter and the second PRACH parameter include at least one of the following parameters:

[0573] a parameter related to a position of a time unit for a PRACH;

[0574] a parameter related to a position of a frequency domain resource for a PRACH;

[0575] a subcarrier spacing for a PRACH;

[0576] an index of a PRACH configuration;

[0577] a cyclic shift value of the PRACH preamble;

[0578] a root sequence index of the PRACH preamble;

[0579] a parameter related to transmission power of a PRACH;

[0580] a threshold value or range for the size of a Message 3 in the random access procedure for selecting a PRACH resource set; and

[0581] a threshold value or range for the RSRP of the downlink pathloss reference of selecting the PRACH resource set.

[0582] For a more detailed description of the first PRACH resource set and the second PRACH resource set, please see the above description of the method performed by the UE (i.e., the on-demand PRACH approach), which will not be repeated here.

[0583] In an embodiment of the present disclosure, one optional implementation is provided for step S202. Specifically, if the second PRACH resource set is not activated, the random access procedure is initiated based on the first PRACH resource set. The second PRACH resource set being not activated includes the second PRACH resource set not being indicated to be activated or being indicated to be deactivated, then the UE randomly selects a PRACH preamble on a RO from the first PRACH resource set to initiate the random access procedure.

[0584] If the second PRACH resource set is activated, the UE performs, but is not limited to, at least one of the following behaviors.

[0585] The first type of the UE behavior: initiating the random access procedure based on the activated second PRACH resource set.

[0586] For example, the UE randomly selects a PRACH preamble on a RO from the activated second PRACH resource set to initiate the random access procedure.

[0587] The second type of the UE behavior: initiating the random access procedure based on the union of the first PRACH resource set and the activated second PRACH resource set.

[0588] For example, the UE randomly selects a PRACH preamble on a RO from the union of the first PRACH resource set and the activated second PRACH resource set to initiate the random access procedure. That is, the PRACH resources for initiating the random access procedure may belong to the first PRACH resource set or the second PRACH resource set.

[0589] The third type of the UE behavior: initiating the random access procedure based on the activated second PRACH resource set; and initiating the random access procedure based on the first PRACH resource set, if the random access is not successful after the activation period of the second PRACH resource set.

[0590] For example, the UE preferentially randomly selects a PRACH preamble on a RO from the second PRACH resource set to initiate the random access procedure. If the number of the PRACH preamble transmission reaches an allowed maximum number and the random access is still not successful, the UE randomly selects a PRACH preamble on a RO from the first PRACH resource set to initiate the random access procedure.

[0591] The fourth type of the UE behavior: initiating the random access procedure based on the first PRACH resource set; and initiating the random access procedure based on the activated second PRACH resource set, if the random access is still not successful after a number of PRACH preamble transmission reaches a preset maximum number.

[0592] For example, the UE preferentially randomly selects a PRACH preamble on a RO from the first PRACH resource set to initiate the random access procedure. If the number of the PRACH preamble transmission reaches an allowed maximum number and the random access is still not successful, the UE randomly selects a PRACH preamble on a RO from the second PRACH resource set to initiate the random access procedure.

[0593] In an embodiment of the present disclosure, in case where the random access procedure is initiated based on the union of the first PRACH resource set and the activated second PRACH resource set, the probabilities the first PRACH resource set and the activated second PRACH resource set are selected are configured separately. In one example, the probability the UE selects the second PRACH resource set to initiate the random access procedure is the same as the probability the UE selects the first PRACH resource set to initiate the random access procedure, i.e., both the probabilities are 0.5. In another example, the probability the UE selects the second PRACH resource set to initiate the random access procedure is different from the probability the UE selects the first PRACH resource set to initiate the random access procedure. That is, the second PRACH resource set and the first PRACH resource set may correspond to different weighting coefficients, e.g. the probabilities of the two may correspond to 0.7 and 0.3 based on the pre-configured weighting coefficients.

[0594] In an embodiment of the present disclosure, information related to activation or deactivation of the PRACH resource set may include, but is not limited to at least one of the following.

[0595] (1) Information that the PRACH resource sets corresponding to one or more PRACH configurations are activated or deactivated.

[0596] That is, the third signal is used to indicate information that the PRACH resource sets corresponding to one or more PRACH configurations are activated. For example, the third signal indicates the indexes of the PRACH configurations.

[0597] (2) Information that the PRACH resource sets corresponding to one or more PRACH parameter values are activated or deactivated.

[0598] That is, the third signal is used to indicate information that the PRACH resources corresponding to one or more PRACH parameter values are activated or deactivated.

[0599] (3) Information that the PRACH resource sets on one or more uplink carriers are activated or deactivated.

[0600] That is, the third signal is used to indicate information that the PRACH resources corresponding to one or more uplink carriers are activated or deactivated. For example, the third signal indicates the indexes of the uplink carriers.

[0601] (4) Information that the PRACH resource sets on one or more initial uplink BWPs are activated or deactivated.

[0602] That is, the third signal is used to indicate information that the PRACH resources on one or more initial uplink BWPs are activated or deactivated. For example, the third signal indicates the indexes of the initial uplink BWPs.

[0603] (5) Information that the PRACH resource sets corresponding to one or more PRACH formats are activated or deactivated.

[0604] That is, the third signal is used to indicate information that the PRACH resources corresponding to one or more PRACH formats are activated or deactivated. For example, the third signal indicates the indexes of the PRACH formats.

[0605] (6) Information that the PRACH resource sets corresponding to one or more PRACH groups are activated or deactivated.

[0606] That is, the third signal is used to indicate information that the PRACH resources corresponding to one or more PRACH groups are activated or deactivated. For example, the third signal indicates the PRACH groups by enumeration.

[0607] (7) Information that the PRACH resource sets corresponding to one or more PRACH resource sets are activated or deactivated.

[0608] That is, the third signal is used to indicate information that the PRACH resources corresponding to one or more PRACH resource sets are activated or deactivated. For example, the third signal indicates the indexes of the PRACH resource sets.

[0609] In an embodiment of the present disclosure, the third signal for activation / deactivation of the PRACH resources may be transmitted by broadcast periodically. That is, the positions of the time / frequency domain resources for transmitting the third signal is configured semi-statically, and the third signal may be monitored by all UEs having the capability for activation / deactivation of the PRACH resources in a cell, including a RRC idle status UE, a RRC inactive status UE, and a RRC connected status UE.

[0610] Optionally, the third signal is carried, but not limited to, by at least one of the following signal:

[0611] (1) a PBCH, i.e., the third signal may be indicated by the PBCH;

[0612] (2) a PDCCH for scheduling the random access response PDSCH;

[0613] (3) a PDCCH for scheduling the system information transmission, i.e., indicated by the scheduling PDCCH (scrambled with the SI-RNTI) of system information;

[0614] (4) a PDCCH for scheduling a paging message PDSCH;

[0615] (5) a PDCCH scrambled with a dedicated RNTI; optionally, the RNTI value is pre-configured by the base station; and

[0616] (6) a downlink control information (DCI) scrambled with a cell radio network temporary identity (Cell-RNTI, C-RNTI), for scheduling the PDSCH or the physical uplink shared channel (PUSCH), that is, the third signal may be transmitted dynamically, e.g. the third signal may be indicated by a group common DCI scrambled with a preset RNTI, or the third signal may be indicated by a scheduling DCI scrambled with the C-RNTI.

[0617] In an embodiment of the present disclosure, the PRACH resources activated / deactivated by the third signal may be configured by the IE PRACH-config-common, which is mainly for contention-based PRACH resources. The PRACH resources activated / deactivated by the third signal transmitted dynamically may be configured by the IE PRACH-config-common or configured by the IE PRACH-config-dedicated, including the contention-based PRACH resources and the contention-free PRACH resources.

[0618] In an embodiment of the present disclosure, in case that the third signal is transmitted dynamically, the activation period may be defined as a preset time period, i.e., the activated PRACH resource set is indicated to only be activated within the preset time period and to be deactivated outside of the preset time period. The length of the activation period may be configured by the base station. Or, the activation period may be defined as a preset number of consecutive ROs, i.e., the PRACH resource set which is indicated to be activated is activated within the preset number of consecutive ROs and is deactivated outside of the preset number of consecutive ROs. Or, the activation period may be defined as a preset number of the PRACH preamble transmission. When the times the UE transmits the PRACH preamble based on the activated PRACH resource set reaches the preset number, the PRACH resource set is assumed to be deactivated. In addition, the starting position of the activation period is a position meeting a fifth preset interval after the third signal is received; or, the starting position of the activation period is a starting position of a first available RO meeting the fifth preset interval after the third signal is received, and the available RO refers to the available RO corresponding to the second PRACH resource set.

[0619] In case that the third signal is transmitted periodically, the size of the activation period is the size of the transmission period of the third signal, and the starting position of the activation period is the starting position of the transmission period of the corresponding third signal. For example, if the third signal received by the UE indicates that the second PRACH resource set is activated, then it means that in the transmission period where the third signal is located, the second PRACH resource set is activated, and in the next transmission period, the second PRACH resource set may be activated or not be activated, which is indicated by the third signal in the transmission period, that is, the activation period totally corresponds to the transmission period. Alternatively, the starting position of the activation period is a position meeting a fifth preset interval after the third signal is received by the UE, and the length of the activation period is the size of the transmission period, i.e., the activation period is staggered with the transmission period by a period of time.

[0620] In an optional implementation, in case that the third signal is transmitted periodically, the UE needs to monitor the third signal on each transmission opportunity for the third signal. If the UE has not monitored the third signal, the UE assumes that the second PRACH resource set is not activated, and within the transmission period where this transmission opportunity is located, the UE initiates the random access procedure based on the first PRACH resource set.

[0621] In another optional implementation, in case that the third signal is transmitted periodically, the UE does not need to monitor signal on each transmission opportunity for the third signal.

[0622] Optionally, if the UE needs to initiate the random access procedure, the UE monitors the third signal on the latest transmission opportunity for the third signal, and initiates the random access procedure on the activated PRACH resource set or the first PRACH resource set based on the indication of the third signal.

[0623] Alternatively, optionally, when a preset condition is satisfied, the UE monitors the third signal in the following time period of a preset length, or UE monitors the third signal in the following earliest transmission opportunity for the third signal, and the UE initiates the random access procedure on the activated PRACH resource set based on the indication of the third signal, otherwise, the UE initiates the random access procedure directly based on the first PRACH resource set.

[0624] The preset condition includes, but not limited to, at least one of the following.

[0625] (1) a request or an indication from a higher layer is received, wherein the request or the indication is about monitoring the third signal or initiating the random access procedure;

[0626] (2) the random access procedure is initiated;

[0627] (3) the size of a Message 3 (Msg3) in the random access procedure is greater than or equal to a first preset threshold value; optionally, the first preset threshold value is configured by the base station;

[0628] (4) the size of a Message 3 in the random access procedure is within a first preset range; optionally, the first preset range is configured by the base station;

[0629] (5) the RSRP value of the downlink pathloss reference is less than a second preset threshold value; optionally, the second preset threshold value is configured by the base station;

[0630] (6) the RSRP value of the downlink pathloss reference is within a second preset range; optionally, the second preset range is configured by the base station;

[0631] (7) the event for triggering the random access procedure is a preset event, and the preset event may be at least one of the events for triggering the random access procedure as described above; for example, the preset event may be a small data transmission, that is, the UE directly transmits the arriving data to the base station through the random access procedure without establishing the RRC connected status;

[0632] (8) the priority of the arriving data is lower than a preset priority, i.e., the value of the priority is greater or equal to the value of the preset priority, the smaller the value of priority, the higher the corresponding priority; optionally, the preset priority is configured by the base station;

[0633] (9) the type of the arriving data is of a preset type; for example, the preset type is control plane (CP) data or user plane (UP) data;

[0634] (10) the index of a logical channel where the arriving data is located or the index of a logical channel group where the arriving data is located is a preset index;

[0635] (11) the size of the amount of the arriving data amount is greater than or equal to a third preset threshold value; optionally, the third preset threshold value is configured by the base station;

[0636] (12) the remaining packet delay budget of the arriving data is greater than or equal to a fourth preset threshold value; optionally, the fourth preset threshold value is configured by the base station, i.e., there are delay requirements for the arriving data of the UE; once a predetermined delay is exceeded, there is no need for transmission, and UE may drop this data packet; and

[0637] (13) the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches the second preset number; optionally, the second preset number is configured by the base station.

[0638] In practical applications, the condition for triggering the UE to monitor the third signal may be pre-configured by the base station. For example, the base station may configure the condition for triggering the UE to monitor the third signal as one or more of the above conditions.

[0639] Optionally, the condition for triggering the UE to monitor the third signal is configured by the system information or configured by the UE specific RRC signal.

[0640] Similarly, in an embodiment of the present disclosure, for a UE of a preset type and / or a UE supporting a preset capability, the UE cannot use the first PRACH resource set to initiate the random access procedure, and may only prioritize the use of the second PRACH resource set to initiate the random access procedure, and thus the UE needs to monitor the third signal. For other UEs, the UEs may use the first PRACH resource set directly to initiate the random access procedure without monitoring the third signal. For example, the UE of the preset type may be an internet of thing (IoT) UE, and the UE with the preset capability may be a UE supporting the capability of monitoring the third signal.

[0641] In the embodiment of the present disclosure, the time unit may be an orthogonal frequency division multiplexing (OFDM) symbol or a single-carrier-FDMA (SC-FDMA) symbol, or the time unit is a slot.

[0642] In an embodiment of the present disclosure, for all mentioned preset intervals, the time duration of the preset interval may be pre-defined or configured by the base station.

[0643] In an embodiment of the present disclosure, there is provided a method performed by a base station in a communication system, the method includes the following steps.

[0644] Step S301: receiving a first signal transmitted by a first UE, the first signal including information related to requesting and / or assisting to activate the PRACH resource sets; and

[0645] Step S302: transmitting, to the first UE, a second signal, the second signal is used for confirming that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or the second signal includes information indicating that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated,

[0646] wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the PRACH resource set to be activated by the first signal requesting and / or assisting;

[0647] the activation period includes at least one of the following:

[0648] the activation period including a time period with a preset length;

[0649] the activation period including a first preset number of consecutive random access occasions (ROs); and

[0650] the activation period including a preset maximum number of PRACH preamble transmission.

[0651] Optionally, the method further includes: transmitting configuration information related to the first PRACH resource set and the second PRACH resource set, wherein the second PRACH resource set needs to be activated for use, and the second PRACH resource set may be activated by request and / or in an assisted manner by the first signal and / or is indicated to be activated by the second signal; wherein the first PRACH resource set includes one or more PRACH resource sets and the second PRACH resource set includes one or more PRACH resource sets.

[0652] Optionally, the first PRACH resource set is associated with a SSB based on a first parameter;

[0653] the second PRACH resource set is associated with a SSB based on a second parameter; and

[0654] wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is the number of SSBs being mapped to each random access opportunity (RO), and / or the number of contention-based PRACH preambles being mapped to each SSB.

[0655] Optionally, if the second PRACH resource set is not activated, the first PRACH resource set is associated with a SSB based on a third parameter;

[0656] if the second PRACH resource set is activated, the union of the first PRACH resource set and the second PRACH resource set is associated with a SSB based on the third parameter; and

[0657] wherein the third parameter is the number of SSBs being mapped to each random access occasion (RO), and / or the number of the contention-based PRACH preambles being mapped to each SSB.

[0658] Optionally, the first PRACH resource set is configured by a first radio resource control information unit; and

[0659] the second PRACH resource set is configured by a second radio resource control information unit;

[0660] wherein the first radio resource control information unit and the second radio resource control information unit are configured by the system information; or

[0661] the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by UE specific RRC signal.

[0662] Optionally, the first PRACH resource set and the second PRACH resource set is obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit.

[0663] Optionally, configuration information for the first PRACH resource set and the second PRACH resource set includes at least one of the following:

[0664] the first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning;

[0665] the first PRACH resource set corresponds to the PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to the PRACH resources on a second uplink carrier;

[0666] the first PRACH resource set corresponds to the PRACH resources on a first initial uplink BWP, and the second PRACH resource set corresponds to the PRACH resources on a second initial uplink BWP;

[0667] the first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format;

[0668] the first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group; and

[0669] wherein the first PRACH parameter and the second PRACH parameter include at least one of the following parameters:

[0670] a parameter related to a position of a time unit for a PRACH;

[0671] a parameter related to a position of a frequency domain resource for a PRACH;

[0672] a subcarrier spacing for a PRACH;

[0673] an index of a PRACH configuration;

[0674] a cyclic shift value of the PRACH preamble;

[0675] a root sequence index of the PRACH preamble;

[0676] a parameter related to transmission power of a PRACH;

[0677] a threshold value or range for the size of a Message 3 in the random access procedure for selecting a PRACH resource set; and

[0678] a threshold value or range for the RSRP of the downlink pathloss reference of selecting the PRACH resource set.

[0679] Optionally, the PRACH resource set includes at least one of the following:

[0680] a set of a part of ROs in the PRACH resource pool;

[0681] a set of a part of PRACH time units in the PRACH resource pool;

[0682] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0683] a set of a part of PRACH preambles in the PRACH resource pool; and

[0684] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0685] Optionally, the first signal is carried by at least one of the following physical signals or physical channels: uplink physical signals; PRACH; and PUCCH.

[0686] Optionally, the first signal carries (in an explicit manner or an implicit manner) first information related to the PRACH resource set to be activated by request, the first information includes at least one of the following:

[0687] information related to the PRACH configuration corresponding to the PRACH resource set to be activated by request;

[0688] information related to PRACH parameter corresponding to the PRACH resource set to be activated by request;

[0689] information related to an uplink carrier corresponding to the PRACH resource set to be activated by request;

[0690] information related to an initial uplink BWP corresponding to the PRACH resource set to be activated by request; information related to a PRACH group corresponding to the PRACH resource set to be activated by request;

[0691] information related to a PRACH format corresponding to the PRACH resource set to be activated by request;

[0692] Information related to the PRACH resource set to be activated by request; and / or

[0693] the first signal carries (in an implicit manner or an explicit manner) related second information for assisting a base station in activation of the PRACH resource set, and the second information includes at least one of the following:

[0694] a type of a UE;

[0695] a size of the Message 3 in the random access procedure;

[0696] a RSRP value of a downlink pathloss reference;

[0697] a priority of arriving data;

[0698] a type of the arriving data;

[0699] an index of a LCH or a LCG where the arriving data is located;

[0700] a size of the amount of the arriving data;

[0701] remaining PDB of arriving data;

[0702] an event for triggering the random access procedure.

[0703] Optionally, the second signal is carried by at least one of the following physical signals or physical channels: downlink physical signals; PBCH; PDCCH and the MAC layer signal.

[0704] Optionally, the PDCCH includes at least one of the following:

[0705] a PDCCH scrambled with a dedicated RNTI;

[0706] a PDCCH for scheduling the random access response PDSCH;

[0707] a PDCCH for scheduling a system information PDSCH; and

[0708] a PDCCH for scheduling a paging message PDSCH.

[0709] The MAC layer signal includes at least one of the following:

[0710] a MAC subheader included in a MAC PDU for carrying the RAR; and

[0711] a MAC RAR.

[0712] Optionally, information indicating that the PRACH resource set to be activated by the first signal requesting and / or assisting is activated, which is included in the second signal, or information indicating that one or more PRACH resource sets are activated, which is included in the second signal, includes at least one of the following:

[0713] information related to the PRACH configurations corresponding to one or more activated PRACH resource sets, respectively;

[0714] information related to PRACH parameters corresponding to one or more activated PRACH resource sets, respectively;

[0715] information related to uplink carriers corresponding to one or more activated PRACH resource sets, respectively;

[0716] information related to initial uplink BWPs corresponding to one or more activated PRACH resource sets, respectively;

[0717] information related to PRACH groups corresponding to one or more activated PRACH resource sets, respectively;

[0718] information related to PRACH formats corresponding to one or more activated PRACH resource sets, respectively;

[0719] indexes of one or more activated PRACH resource sets; and

[0720] bitmap information for indicating whether a plurality of PRACH resource sets are activated or not, respectively.

[0721] Optionally, in case that the first signal is carried by a PRACH,

[0722] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure are configured by different radio resource control information units respectively;

[0723] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure are obtained by division of the PRACH resource pool; and

[0724] the PRACH resources for carrying a first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources.

[0725] Optionally, in case that the PRACH resources for carrying the first signal and the PRACH resources for initiating the random access procedure share the same PRACH resources, the shared PRACH resources belong to the first PRACH resource set.

[0726] Optionally, the UE is triggered to transmit the first signal when at least one of the following conditions is met for the UE or the random access procedure:

[0727] a request or an indication from a higher layer is received, wherein the request or the indication is about transmitting the first signal or initiating the random access procedure;

[0728] the random access procedure is initiated;

[0729] the size of a Message 3 in the random access procedure is greater than or equal to a first preset threshold value;

[0730] the size of a Message 3 in the random access procedure is within a first preset range;

[0731] the RSRP value of the downlink pathloss reference is less than the a second preset threshold value;

[0732] the RSRP value of the downlink pathloss reference is within a second preset range;

[0733] the event for triggering the random access procedure is a preset event;

[0734] the priority of the arriving data is lower than a preset priority;

[0735] the type of the arriving data is of a preset type;

[0736] the index of a logical channel where the arriving data is located or the index of a logical channel group where the arriving data is located is a preset index;

[0737] the size of the amount of the arriving data is greater than or equal to a third preset threshold value;

[0738] the remaining packet delay budget of the arriving data is less than a fourth preset threshold value, or the remaining packet delay budget of the arriving data is greater than or equal to the fourth preset threshold value; and

[0739] the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches a second preset number.

[0740] Optionally, the condition for triggering the UE to transmit the first signal is configured by the system information or configured by the UE specific RRC signal.

[0741] The UE is a UE of a preset type and / or a UE supporting a preset capability.

[0742] In an embodiment of the present disclosure, there is provided another method performed by a base station in a communication system, the method includes the following steps.

[0743] Step S401: transmitting, to the UE, a third signal, the third signal including information related to activation or deactivation of the PRACH resource set;

[0744] wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the activated PRACH resource sets;

[0745] the activation period includes at least one of the following:

[0746] the activation period including a time period with a preset length;

[0747] the activation period including a first preset number of consecutive random access occasions (ROs); and

[0748] the activation period including a preset maximum number of PRACH preamble transmission.

[0749] Optionally, prior to the step S401, the method further includes: transmitting configuration information related to the first PRACH resource set and the second PRACH resource set, wherein the second PRACH resource set needs to be activated for use, the second PRACH resource set may be indicated by the third signal to be activated or deactivated; wherein the first PRACH resource set includes one or more PRACH resource sets and the second PRACH resource set includes one or more PRACH resource sets.

[0750] Optionally, the first PRACH resource set is associated with a synchronization signal block (SSB) based on a first parameter;

[0751] the second PRACH resource set is associated with a SSB based on a second parameter; and

[0752] wherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is the number of SSBs being mapped to each RO and / or the number of contention-based PRACH preambles being mapped to each SSB.

[0753] Optionally, if the second PRACH resource set is not activated, the first PRACH resource set is associated with a SSB based on a third parameter;

[0754] if the second PRACH resource set is activated, the union of the first PRACH resource set and the second PRACH resource set is associated with SSBs based on the third parameter; and

[0755] wherein the third parameter is the number of SSBs being mapped to each random access occasion (RO), and / or the number of the contention-based PRACH preambles being mapped to each SSB.

[0756] Optionally, the first PRACH resource set is configured by a first radio resource control information unit; and

[0757] the second PRACH resource set is configured by a second radio resource control information unit;

[0758] wherein the first radio resource control information unit and the second radio resource control information unit are configured by the system information; or

[0759] the first radio resource control information unit is configured by the system information, and the second radio resource control information unit is configured by UE specific radio resource control (RRC) signal.

[0760] Optionally, the first PRACH resource set and the second PRACH resource set are obtained by partitioning a PRACH resource pool configured by a third radio resource control information unit.

[0761] Optionally, configuration information for the first PRACH resource set and the second PRACH resource set includes at least one of the following:

[0762] the first PRACH resource set corresponds to a first PRACH parameter, and the second PRACH resource set corresponds to a second PRACH parameter, wherein the first PRACH parameter and the second PRACH parameter are configured separately and have the same physical meaning;

[0763] the first PRACH resource set corresponds to the PRACH resources on a first uplink carrier, and the second PRACH resource set corresponds to the PRACH resources on a second uplink carrier;

[0764] the first PRACH resource set corresponds to the PRACH resources on a first initial uplink bandwidth part (BWP), and the second PRACH resource set corresponds to the PRACH resources on a second initial uplink BWP;

[0765] the first PRACH resource set corresponds to a first PRACH format, and the second PRACH resource set corresponds to a second PRACH format;

[0766] the first PRACH resource set corresponds to a first PRACH group, and the second PRACH resource set corresponds to a second PRACH group; and

[0767] wherein the first PRACH parameter and the second PRACH parameter include at least one of the following parameters:

[0768] a parameter related to a position of a time unit for a PRACH;

[0769] a parameter related to a position of a frequency domain resource for a PRACH;

[0770] a subcarrier spacing for a PRACH;

[0771] an index of a PRACH configuration;

[0772] a cyclic shift value of the PRACH preamble;

[0773] a root sequence index of the PRACH preamble;

[0774] a parameter related to transmission power of a PRACH;

[0775] a threshold value or range for the size of a Message 3 in the random access procedure for selecting a PRACH resource set; and

[0776] a threshold value or range for the RSRP of the downlink pathloss reference of selecting the PRACH resource set.

[0777] Optionally, the PRACH resource set includes at least one of the following:

[0778] a set of a part of ROs in the PRACH resource pool;

[0779] a set of a part of PRACH time units in the PRACH resource pool;

[0780] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0781] a set of a part of PRACH preambles in the PRACH resource pool; and

[0782] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0783] Optionally, information related to activation or deactivation of the PRACH resource set includes at least one of the following:

[0784] information related to the PRACH configurations corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0785] information related to PRACH parameters corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0786] information related to uplink carriers corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0787] information related to an initial uplink BWP corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0788] information related to PRACH groups corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0789] information related to PRACH formats corresponding to one or more activated or deactivated PRACH resource sets, respectively;

[0790] indexes of one or more activated or deactivated PRACH resource sets; and

[0791] bitmap information for indicating whether a plurality of PRACH resource sets are activated or not, respectively.

[0792] Optionally, the PRACH resource set includes at least one of the following:

[0793] a set of a part of ROs in the PRACH resource pool;

[0794] a set of a part of PRACH time units in the PRACH resource pool;

[0795] a set of a part of PRACH frequency domain resources in the PRACH resource pool;

[0796] a set of a part of PRACH preambles in the PRACH resource pool; and

[0797] a set of a part of PRACH preambles on a part of ROs in the PRACH resource pool.

[0798] Optionally, the third signal is carried by at least one of the following signal:

[0799] a PBCH; and

[0800] a PDCCH for scheduling the random access response PDSCH;

[0801] a PDCCH for scheduling a system information PDSCH; and

[0802] a PDCCH for scheduling a paging message PDSCH.

[0803] a PDCCH scrambled with a dedicated RNTI; and

[0804] a DCI scrambled with a C-RNTI, for scheduling the PDSCH or the PUSCH.

[0805] Optionally, the condition for triggering the UE to monitor the third signal is configured by the system information or configured by the UE specific RRC signal.

[0806] Optionally, the preset condition includes at least one of the following:

[0807] a request or an indication from a higher layer is received, wherein the request or the indication is about monitoring the third signal or initiating the random access procedure;

[0808] the size of a Message 3 in the random access procedure is greater than or equal to a first preset threshold value;

[0809] the size of a Message 3 in the random access procedure is within a first preset range;

[0810] the RSRP value of the downlink pathloss reference is less than a second preset threshold value;

[0811] the RSRP value of the downlink pathloss reference is within a second preset range;

[0812] the event for triggering the random access procedure is a preset event;

[0813] the priority of the arriving data is lower than a preset priority;

[0814] the type of the arriving data is of a preset type;

[0815] the index of a logical channel where the arriving data is located or the index of a logical channel group where the arriving data is located is a preset index;

[0816] the size of the amount of the arriving data is greater than or equal to a third preset threshold value;

[0817] the remaining packet delay budget of the arriving data is less than a fourth preset threshold value, or the remaining packet delay budget of the arriving data is greater than or equal to the fourth preset threshold value; and

[0818] the random access is not successful after the number of PRACH preamble transmission on the first PRACH resource set reaches a second preset number.

[0819] Optionally, the UE is a UE of a preset type and / or a UE supporting a preset capability.

[0820] The implementation principles of the method performed by the base station according to embodiments of the present disclosure correspond to the method performed by the UE, and has a corresponding technical effect. The detailed functional description for base station side may specifically refer to the description of the corresponding method of the UE side described above and will not be repeated here.

[0821] An embodiment of the present disclosure provides an electronic device, including: a transceiver, which is configured to transmit and receive signals; and, a processor, which is coupled to the transceiver and configured to implement the steps in the above method embodiments. Optionally, the electronic device may refer to the UE, the processor is configured to implement steps of the embodiments of various methods performed by the UE, and its detailed functional description and the achieved beneficial effects may specifically refer to the above description in the embodiments of various methods performed by the UE and will not be repeated here. Optionally, the electronic device may refer to the base station, the processor is configured to implement steps of the embodiments of various methods performed by the base station, and its detailed functional description and the achieved beneficial effects may specifically refer to the above description in the embodiments of various methods performed by the base station and will not be repeated here. In practical applications, the UE or the base station may be construed as different network nodes.

[0822] The embodiments of the present disclosure further provide an electronic device, the electronic device including at least one transceiver and at least one processor coupled to at least one transceiver, at least one processor is configured to perform the methods provided in any of the optional embodiments of the present disclosure.

[0823] FIG. 8 shows a schematic structure diagram of an electronic device to which the embodiment of the present disclosure is applied. As shown in FIG. 8, the electronic device 4000 shown in FIG. 8 may include a processor 4001 and a memory 4003. The processor 4001 is connected with the memory 4003, for example, through the bus 4002. Optionally, the electronic device 4000 may further include a transceiver 4004 which may be used for data interaction between the electronic device and other electronic devices, such as data transmission and / or data reception and so on. It should be noted that, in practical applications, the transceiver 4004 is not limited to one, and the structure of the electronic device 4000 does not constitute a limitation to the embodiments of the present disclosure. Optionally, the electronic device may be a first network node, a second network node or a third network node.

[0824] The processor 4001 may be a central processing unit (CPU), a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It may implement or execute various exemplary logical blocks, modules and circuits described in connection with the present disclosure. The processor 4001 may also be a combination for realizing computing functions, such as a combination including one or more microprocessors, a combination of a DSP and a microprocessor, and so on.

[0825] The bus 4002 may include a path to transfer information between the components described above. The bus 4002 may be a peripheral component interconnect (PCI) bus or an extended industry standard architecture (EISA) bus and so on. The bus 4002 may be divided into an address bus, a data bus, a control bus, and so on. For ease of presentation, the bus is represented by only one thick line in FIG. 8. However, it does not mean that there is only one bus or one type of buses.

[0826] The memory 4003 may be a read only memory (ROM) or other types of static storage devices that may store static information and instructions, a random access memory (RAM) or other types of dynamic storage devices that may store information and instructions, it may also be an electrically erasable and programmable read only memory (EEPROM), a compact disc read only memory (CD-ROM) or other optical disk storages, optical disk storage s(including a compressed compact disc, a laser disc, a compact disc, a digital versatile disc, a blue-ray disc, etc.), a magnetic disk storage media, other magnetic storage devices, or any other medium capable of carrying or storing computer programs and capable of being read by a computer, without limitation therein.

[0827] The memory 4003 is configured to store computer programs for executing the embodiments of the present disclosure, and the execution is controlled by the processor 4001. The processor 4001 is configured to execute the computer programs stored in the memory 4003 to implement the steps shown in the foregoing method embodiments.

[0828] An embodiment of the present disclosure provides a computer readable storage medium having computer programs stored thereon that, when executed by a processor, may implement the steps and corresponding contents in the above method embodiments.

[0829] An embodiment of the present disclosure further provides a computer program product, comprising computer programs that, when executed by a processor, may implement the steps and corresponding contents in the above method embodiments.

[0830] The terms "first", "second", "third", "fourth", "1", "2", etc. (if any) in the specification and claims of the present disclosure and the accompanying drawings are used for distinguishing similar objects, rather than describing a particular order or precedence. It is to be understood that the terms used is such a way are interchangeable in the appropriate cases, such that the embodiments of the present disclosure described herein may be implemented in orders other than those illustrated or described in the text.

[0831] It should be understood that while the flow diagrams of embodiments of the present disclosure indicate the individual operational steps by arrows, the order in which these steps are performed is not limited to the order indicated by the arrows. Unless explicitly stated herein, in some implementation scenarios of embodiments of the present disclosure, the implementation steps in the respective flowcharts may be performed in other orders as desired. In addition, some, or all of the steps in each flowchart may include multiple sub-steps or multiple phases based on the actual implementation scenario. Some or all of these sub-steps or stages may be executed at the same moment, and each of these sub-steps or stages may also be executed at different moments separately. The order of execution of these sub-steps or stages may be flexibly configured according to requirements in different scenarios of execution time, and the embodiments of the present disclosure are not limited thereto.

[0832] The above-mentioned description and the drawings are provided merely as examples to help readers to understand the present disclosure, and they should not be interpreted or aim to limit the scope of the present disclosure in any way. Although some embodiments are provided, it is apparent for those skilled in the art to adopt other similar implementation means based on the technical idea of the present disclosure without departing from the technical concept of the solution of the present disclosure.

Claims

1.A method performed by a user equipment (UE) in a communication system, the method comprising:transmitting a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set; andduring an activation period of the PRACH resource set, initiating a random access procedure, based on the PRACH resource set activated based on the first signal;wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.2.The method of claim 1, wherein initiating the random access procedure comprises:receiving a second signal, wherein the second signal is used for confirming that the PRACH resource set is activated, or the second signal includes information indicating that the PRACH resource set is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated; andinitiating the random access procedure based on the activated PRACH resource set.3.The method of claim 2, further comprising:prior to transmitting the first signal, receiving configuration information related to a first PRACH resource set and a second PRACH resource set, wherein the second PRACH resource set is activated based on the first signal or is activated based on indication of the second signal; andwherein the first PRACH resource set includes one or more PRACH resource sets, and the second PRACH resource set includes one or more PRACH resource sets.4.The method of claim 3, wherein the first PRACH resource set is associated with a synchronization signal block (SSB) based on a first parameter,the second PRACH resource set is associated with a SSB based on a second parameter; andwherein the first parameter and the second parameter are configured separately, and each of the first parameter and the second parameter is a number of SSBs mapped to each RO or a number of contention-based PRACH preambles mapped to each SSB.5.The method of claim 3, wherein in case that the second PRACH resource set is not activated, the first PRACH resource set is associated with a SSB based on a third parameter;in case that the second PRACH resource set is activated, a union of the first PRACH resource set and the second PRACH resource set is associated with the SSB based on the third parameter; andwherein the third parameter is a number of SSBs mapped to each RO or a number of contention-based PRACH preambles mapped to each SSB.6.The method of claim 3, further comprising:after transmitting the first signal, monitoring the second signal at a first position meeting a first preset interval, or within a first time window from the first position, or on a first transmission opportunity for the second signal after the first position.7.The method of claim 3, further comprising:determining a second time window where the first signal is located, wherein the second time window includes a plurality of transmission opportunities for the first signal;after an ending position of the second time window, monitoring the second signal at a second position meeting a second preset interval, or within a first time window from the second position, or on a first transmission opportunity for the second signal after the second position.8.The method of claim 1,wherein the preset length of the time period is configured by higher layer signal or indicated by the second signal,wherein the first preset number of the consecutive ROs is configured by the higher layer signal or indicated by the second signal andwherein the preset maximum number of PRACH preamble transmission is configured by the higher layer signal or indicated by the second signal.9.The method of claim 1, wherein a starting position of the activation period includes at least one of the following:a position meeting a third preset interval after the first signal is transmitted;a starting position of a first available RO meeting the third preset interval after the first signal is transmitted;a position meeting a fourth preset interval after the second signal is received; anda starting position of a first available RO meeting the fourth preset interval after the second signal is received.10.The method of claim 1, wherein during the activation period, a maximum number of PRACH preambles transmitted based on the PRACH resource set is determined based on a duration of the activation period.11.The method of claim 1, further comprising:initiating the random access procedure based on a first PRACH resource set, in case that a random access is not successful after an end of the activation period.12.The method of claim 3, wherein the UE is triggered to transmit the first signal in case that at least one of following conditions is met:receiving a request or an indication from a higher layer, wherein the request or the indication is about transmitting the first signal or initiating the random access procedure;the random access procedure is initiated:in case that a size of Message 3 in the random access procedure is greater than or equal to a first preset threshold value;in case that the size of the Message 3 in the random access procedure is within a first preset range;in case that a RSRP (reference signal received power) value of a downlink pathloss reference is less than a second preset threshold value;in case that the RSRP value of the downlink pathloss reference is within a second preset range;in case that an event for triggering the random access procedure is a preset event;in case that a priority of an arriving data is lower than a preset priority;in case that a type of the arriving data is of a preset type;in case that an index of a logical channel where the arriving data is located or an index of a logical channel group where the arriving data is located is a preset index;in case that a size of data amount of the arriving data is greater than or equal to a third preset threshold value;in case that remaining packet delay budget of the arriving data is less than a fourth preset threshold value, or the remaining packet delay budget of the arriving data is greater than or equal to the fourth preset threshold value; andin case that a random access is not successful after a number of PRACH preamble transmission on the first PRACH resource set reaches a second preset number.13.A method performed by a base station in a communication system, the method comprising:receiving, from a user equipment (UE), a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set; andtransmitting, to the UE, a second signal, wherein the second signal is used for confirming that the PRACH resource set is activated, or the second signal includes information indicating that the PRACH resource set is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated,wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the PRACH resource set,wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.14.A user equipment (UE) in a communication system, the UE comprising:a transceiver; andat least one processor coupled with the transceiver and configured to:transmit a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set, andduring an activation period of the PRACH resource set, initiate a random access procedure, based on the PRACH resource set activated based on the first signal,wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.15.A base station in a communication system, the base station comprising:a transceiver; andat least one processor coupled with the transceiver and configured to:receive, from a user equipment (UE), a first signal including information related to requesting or assisting to activate a physical random access channel (PRACH) resource set, andtransmit, to the UE, a second signal, wherein the second signal is used for confirming that the PRACH resource set is activated, or the second signal includes information indicating that the PRACH resource set is activated, or the second signal includes information indicating that one or more PRACH resource sets are activated,wherein during an activation period of the PRACH resource set, a random access procedure is initiated based on the PRACH resource set,wherein the activation period includes at least one of a time period with a preset length, a first preset number of consecutive random access occasions (ROs) and a preset maximum number of PRACH preamble transmission.

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