Signal transmission method and device, and storage medium

Abstract

Systems and methods for signal transmission may include a wireless communication device receiving first information in signaling from a wireless communication node, the first information indicating a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission. The wireless communication device may transmit a PRACH signal corresponding to the DL signal index to the wireless communication node in a random access (RA) occasion determined by the mode.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications, including but not limited to systems, devices, methods, and computer-readable media for signal transmission. Technical Field

[0003] The Third Generation Partnership Project (3GPP), a standardization organization, is currently in the process of specifying a new air interface called 5G New Radio (5G NR) and the next generation packet core network (NG-CN or NGC). The 5G NR will have three main components: 5G access network (5G-AN), 5G core network (5GC) and user equipment (UE). To facilitate the implementation of different data services and requirements, the elements of 5GC (also called network functions) have been simplified, some of which are software-based and some are hardware-based so that they can be adjusted according to needs. Summary of the invention

[0004] The example embodiments disclosed herein are directed to solving problems associated with one or more difficulties presented in the prior art, as well as providing additional features that will become apparent by reference to the following detailed description when combined with the accompanying drawings. According to various embodiments, example systems, methods, devices, and computer program products are disclosed herein. However, it should be understood that these embodiments are presented by way of example and are not limiting, and it will be apparent to those of ordinary skill in the art who have read this disclosure that various modifications may be made to the disclosed embodiments while remaining within the scope of this disclosure.

[0005] At least one aspect relates to a system, method, apparatus, or computer-readable medium. A wireless communication device may receive first information in signaling from a wireless communication node, the first information indicating a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission. The wireless communication device may transmit a PRACH signal corresponding to a DL signal index to the wireless communication node in a random access (RA) opportunity determined by the mode.

[0006] The first information includes at least one of the following: information of at least one paging opportunity; information of at least one synchronization signal block (SSB); an indication of multiple RA opportunities; an indication of a PRACH configuration period; an indication of an association period, which includes multiple configured PRACH configuration periods; an indication of an association mode period; an indication of a validity duration for multiple RACH opportunities; an indication of multiple configured valid or available PRACH configuration periods; an indication of a duration for multiple configured valid or available PRACH configuration periods; an indication of a duration for multiple valid or available association periods; an indication of an offset for indicating a starting position of an RA opportunity; or an indication of a starting position of at least one of a validity duration for multiple RACH opportunities, a duration for multiple configured valid or available PRACH configuration periods, a duration for multiple valid or available association periods, a PRACH opportunity, a PRACH configuration period, an association period, or an association mode period.

[0007] At least a portion of the first information may be used to determine at least one valid or available RA opportunity for transmission of a PRACH signal. A PRACH configuration period may satisfy at least one of the following: (i) the PRACH configuration period is at most max_x milliseconds (ms) or at least min_x ms in length, where at least one of min_x is not greater than 10 or max_x is not less than 160 is satisfied, or (ii) a maximum value of a PRACH configuration index configured by higher layer signaling is not less than M and not greater than M+α*n, where M is a positive integer and n is the number of PRACH configuration periods where each PRACH configuration period is greater than 160 ms. The parameter α can be a value in the range of 1 to 11, and the PRACH configuration period is configured for at least one of the following preamble formats: 0, 1, 2, 3, A1, A2, A3, B4, C0 or C2; or α can be a value in the range of 1 to 19, and the PRACH configuration period is configured for at least one of the following preamble formats: A1, A2, A3, B1, B4, C0 or C2, A1 / B1, A2 / B2 or A3 / B3.

[0008] At least one of the following may be satisfied: the number of configured PRACH configuration periods is an integer not less than n1 and not greater than n2 in a defined set, the PRACH configuration period (x) in milliseconds (ms) is an integer not less than min_x and not greater than max_x, where min_x is not greater than 10 or max_x is not less than 160, or n1 is not greater than 1 and n2 is not less than

[0009] The association pattern period may include one or more association periods and may be determined so that the pattern between RA opportunities and SSB indices is at most every max_x or min_x*n2 or every T SSB Repeat: Where T SSB is the periodicity of the SSB and is greater than the maximum of the associated pattern period or associated period or PRACH configuration period, or greater than 160 ms. A PRACH opportunity that is not associated with an SSB index after an integer number of associated periods may not be used for PRACH transmission.

[0010] The SSB may include one or more synchronization signals and a physical broadcast channel (SS / PBCH), an SSB with a large periodicity, or a small SSB. The situation where the PRACH configuration period is greater than 160ms, or min_x or max_x is greater than 160ms is triggered by at least one of the following events: the wireless communication device is configured to support an SSB different from the SSB in the new radio (NR) version 17; the wireless communication device is configured to support a release version different from NR version 17; the wireless communication device is configured to support a PRACH configuration period greater than 160ms; the wireless communication device is configured to support a preamble format; or the wireless communication device is configured to support an RA type.

[0011] The signaling may include at least one of the following: cell-specific downlink control information (DCI) signaling, group-common DCI, wireless communication device-specific DCI, medium access control control element (MAC CE) signaling, radio resource control (RRC) signaling, or system information block (SIB) signaling. The cell-specific DCI may include information for one or more wireless communication devices in a cell, which is used to indicate at least one valid or available RA opportunity for transmission of a PRACH signal. The group-common DCI may have a DCI format 2_7 with a cyclic redundancy check (CRC) scrambled by a radio network temporary identifier (RNTI), or a DCI format 1_0 with a CRC scrambled by a paging RNTI (P-RNTI), or a DCI format 2_6 with a CRC scrambled by a power saving RNTI (PS-RNTI), or a DCI format 2-0, 2-1, 2-2, 2-3, 2-4, or 2-5 or a defined DCI format to include information of at least one valid or available RA opportunity for transmission of a PRACH signal. The wireless communication device specific DCI may have DCI format 0-1, 0-2, 1-1 or 1-2 or a defined DCI format to include information of at least one valid or available RA opportunity for transmission of a PRACH signal.

[0012] The wireless communication device may also determine the number of contention-based RA preambles for each SSB index for each valid RA opportunity based on a result of dividing the total number of RA preambles by the number of SSB indexes, wherein at least one of the following is satisfied: the number of contention-based RA preambles for each SSB index for each valid RA opportunity is equal to the result, or the result is rounded up to the nearest integer, or the result is rounded down to the nearest integer; the total number of RA preambles is indicated via downlink control information (DCI) signaling, or the total number of RA preambles is greater than or less than the number of most recently configured SSB indexes associated with an RA opportunity.

[0013] If a New Radio (NR) Release 17 SSB or a SSB that is new to an NR Release 17 SSB is configured for a wireless communication device, the wireless communication device may determine at least one of: for each valid RA opportunity, the SSB that is new to an NR Release 17 SSB is selected with a higher priority than the SSB in NR Release 17; or at least one defined parameter for PRACH transmission associated with the SSB that is new to an NR Release 17 SSB. The at least one defined parameter may be configured to indicate a threshold value of a synchronization signal reference signal received power (SS-RSRP) associated with the SSB that is new to an NR Release 17 SSB.

[0014] The wireless communication device may determine the number of contention-based preambles mapped to each enhanced SSB index based on the result of dividing the total number of contention-based preambles configured by the defined parameters by the enhanced SSB index. The number of contention-based preambles mapped to each enhanced SSB index may be equal to the result, the result rounded up to the nearest integer, the result rounded down to the nearest integer, or the result rounded up to the nearest integer.

[0015] When enhanced SSB is configured or the number of enhanced SSB indexes is configured, or enhanced SSB is configured for a two-step RA type: a defined number of SSBs mapped to each RA opportunity for the two-step RA type and a defined number of contention-based RA preambles mapped to each SSB are used for each enhanced SSB; or parameters of the enhanced SSB are configured to indicate the number of SSB indexes mapped to each PRACH opportunity for the two-step RA type and the number of contention-based RA preambles mapped to each SSB index.

[0016] When PRACH opportunities are shared between a two-step RA type and a four-step RA type, a parameter for enhanced SSB may be configured to indicate the number of contention-based RA preambles of the two-step RA type mapped to each SSB. The wireless communication device is configured to support an SSB different from the SSB in New Radio (NR) Release 17.

[0017] At least one aspect relates to a system, method, apparatus, or computer-readable medium. A wireless communication node may transmit first information in signaling to a wireless communication device, the first information indicating a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission. The wireless communication node may receive a PRACH signal corresponding to a DL signal index from the wireless communication device in a random access (RA) opportunity determined by the mode.

[0018] The systems, devices, methods, and computer-readable media described herein include novel signal transmission / reception approaches. In particular, the systems, devices, methods, and computer-readable media described herein utilize the impact of downlink (DL) signaling on uplink (UL) random access procedures to ensure UE initial access performance and network energy saving without increasing UE power and degrading UE experience. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various example embodiments of the present solution are described in detail below with reference to the following figures or drawings. The drawings are provided for illustration purposes only and depict only example embodiments of the present solution to facilitate the reader's understanding of the present solution. Therefore, the drawings should not be considered as limiting the breadth, scope or applicability of the present solution. It should be noted that for clarity and ease of illustration, these drawings are not necessarily drawn to scale.

[0020] Figure 1 An example cellular communication network is shown in accordance with an embodiment of the present disclosure, in which the techniques disclosed herein may be implemented;

[0021] Figure 2 A block diagram showing example base station and user equipment apparatus according to some embodiments of the present disclosure is shown;

[0022] Figure 3 A flow chart illustrating an example signal transmission method performed by a user equipment or a wireless communication device according to some embodiments of the present disclosure is shown;

[0023] Figure 4 A flow chart illustrating an example signal reception method performed by a base station or wireless communication node according to some embodiments of the present disclosure is shown;

[0024] Figure 5A schematic diagram illustrating an example scenario in which multiple random access (RA) opportunities (RO) occurring before a paging opportunity (PO) may be used for PRACH signal transmission according to some embodiments of the present disclosure is shown;

[0025] Figure 6 shows a schematic diagram illustrating an example scenario in which multiple random access (RA) opportunities (RO) occurring after a PO may be used for PRACH signal transmission according to some embodiments of the present disclosure;

[0026] Figure 7 shows a schematic diagram illustrating an example scenario in which multiple ROs associated with four SSBs preceding a PO may be used for PRACH signal transmission according to some embodiments of the present disclosure;

[0027] Figure 8 shows a schematic diagram illustrating an example scenario in which multiple ROs associated with three SSBs preceding a PO may be used for PRACH signal transmission according to some embodiments of the present disclosure; and

[0028] Fig. 9 A diagram is shown showing an example mapping relationship from SSB to preamble for RA according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0029] I. Mobile communication technology and environment

[0030] Figure 1 An example wireless communication network and / or system 100 is shown in accordance with an embodiment of the present disclosure, in which the techniques disclosed herein may be implemented. In the discussion that follows, the wireless communication network 100 may be any wireless network, such as a cellular network or a narrowband Internet of Things (NB-IoT) network, and is referred to herein as "network 100." Such an example network 100 includes a base station 102 (hereinafter referred to as "BS 102"; also referred to as a wireless communication node) and a user equipment 104 (hereinafter referred to as "UE 104"; also referred to as a wireless communication device), which may communicate with each other via a communication link 110 (e.g., a wireless communication channel); and a cluster of cells 126, 130, 132, 134, 136, 138, and 140 covering a geographic area 101. In Figure 1 1, BS 102 and UE 104 are contained within the respective geographic boundaries of cell 126. Each of the other cells 130, 132, 134, 136, 138, and 140 may include at least one base station operating at its allocated bandwidth to provide adequate radio coverage to its intended users.

[0031] For example, BS 102 may operate at the allocated channel transmission bandwidth to provide sufficient coverage to UE 104. BS 102 and UE 104 may communicate via downlink radio frames 118 and uplink radio frames 124, respectively. Each radio frame 118 / 124 may be further divided into subframes 120 / 127, which may include data symbols 122 / 128. In the present disclosure, BS 102 and UE 104 are described herein as non-limiting examples of "communication nodes", which may generally practice the methods disclosed herein. According to various embodiments of the present solution, such communication nodes may be capable of wireless and / or wired communication.

[0032] Figure 2 A block diagram of an example wireless communication system 200 for transmitting and receiving wireless communication signals (e.g., OFDM / OFDMA signals) according to some embodiments of the present solution is shown. The system 200 may include components and elements configured to support known or conventional operating features that need not be described in detail herein. In an illustrative embodiment, the system 200 may be used in a wireless communication environment (such as Figure 1 The invention relates to a method for communicating (eg, transmitting and receiving) data symbols in a wireless communication environment 100 of the present invention, as described above.

[0033] System 200 generally includes a base station 202 (hereinafter referred to as "BS 202") and a user equipment 204 (hereinafter referred to as "UE 204"). BS 202 includes a BS (base station) transceiver module 210, a BS antenna 212, a BS processor module 214, a BS memory module 216, and a network communication module 218, each of which is coupled and interconnected to each other via a data communication bus 220 when necessary. UE 204 includes a UE (user equipment) transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each of which is coupled and interconnected to each other via a data communication bus 240 when necessary. BS 202 communicates with UE 204 via a communication channel 250, which can be any wireless channel or other medium suitable for data transmission as described herein.

[0034] As is understood by those skilled in the art, in addition to Figure 2In addition to the modules shown, system 200 may also include any number of modules. It will be appreciated by those skilled in the art that the various illustrative blocks, modules, circuits, and processing logic described in conjunction with the embodiments disclosed herein may be implemented in hardware, computer-readable software, firmware, or any actual combination thereof. In order to clearly illustrate this interchangeability and compatibility of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps are generally described in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software may depend on specific applications and design constraints imposed on the entire system. A technician familiar with the concepts described herein may implement such functionality in a suitable manner for each specific application, but such implementation decisions should not be interpreted as limiting the scope of the present disclosure.

[0035] According to some embodiments, the UE transceiver 230 may be referred to herein as an "uplink" transceiver 230, which includes a radio frequency (RF) transmitter and an RF receiver, each including circuits coupled to an antenna 232. A duplex switch (not shown) may alternately couple the uplink transmitter or receiver to the uplink antenna in a time division duplex manner. Similarly, according to some embodiments, the BS transceiver 210 may be referred to herein as a "downlink" transceiver 210, which includes a radio frequency (RF) transmitter and an RF receiver, each including circuits coupled to an antenna 212. The downlink duplex switch may alternately couple the downlink transmitter or receiver to the downlink antenna 212 in a time division duplex manner. The operation of the two transceiver modules 210 and 230 may be coordinated in time such that while the downlink transmitter is coupled to the downlink antenna 212, the uplink receiver circuit is coupled to the uplink antenna 232 for receiving transmissions on the wireless transmission link 250. Stated conversely, the operation of the two transceiver modules 210 and 230 may be coordinated in time such that while the uplink transmitter is coupled to the uplink antenna 232, the downlink receiver is coupled to the downlink antenna 212 for receiving transmissions over the wireless transmission link 250. In some embodiments, there is tight time synchronization with minimal guard time between changes in duplex direction.

[0036] The UE transceiver 230 and the base station transceiver 210 are configured to communicate via a wireless data communication link 250 and cooperate with an appropriately configured RF antenna arrangement 212 / 232 capable of supporting a specific wireless communication protocol and modulation scheme. In some illustrative embodiments, the UE transceiver 230 and the base station transceiver 210 are configured to support industry standards such as Long Term Evolution (LTE) and emerging 5G standards. However, it should be understood that the present disclosure is not necessarily limited to specific standards and associated protocols in application. More specifically, the UE transceiver 230 and the base station transceiver 210 can be configured to support alternative or additional wireless data communication protocols, including future standards or variations thereof.

[0037] According to various embodiments, BS 202 may be, for example, an evolved Node B (eNB), a serving eNB, a target eNB, a femtocell or a microcell. According to some embodiments, UE 204 may be embodied in various types of user equipment, such as a mobile phone, a smart phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, a wearable computing device, etc. Processor modules 214 and 236 may be implemented or implemented with a general purpose processor, a content addressable memory, a digital signal processor, an application specific integrated circuit, a field programmable gate array, any suitable programmable logic device, a discrete gate or transistor logic, a discrete hardware component, or any combination thereof, and are designed to perform the functions described herein. In this way, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, or the like. The processor may also be implemented as a combination of computing devices, for example, a combination of a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a digital signal processor core, or any other such configuration.

[0038] In addition, the steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be directly embodied in hardware, firmware, software modules executed by processor modules 214 and 236, respectively, or any practical combination thereof. Memory modules 216 and 234 may be implemented as RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art. In this regard, memory modules 216 and 234 may be coupled to processor modules 210 and 230, respectively, so that processor modules 210 and 230 may read information from and write information to memory modules 216 and 234, respectively. Memory modules 216 and 234 may also be integrated into their respective processor modules 210 and 230. In some embodiments, memory modules 216 and 234 may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions executed by processor modules 210 and 230, respectively. Memory modules 216 and 234 may also each include non-volatile memory for storing instructions to be executed by processor modules 210 and 230, respectively.

[0039] The network communication module 218 generally represents the hardware, software, firmware, processing logic, and / or other components of the base station 202, which enable two-way communication between the BS transceiver 210 and other network components and the communication node configured to communicate with the base station 202. For example, the network communication module 218 can be configured to support Internet or WiMAX traffic. In a typical deployment, without limitation, the network communication module 218 provides an 802.3 Ethernet interface so that the base station transceiver 210 can communicate with a computer network based on a conventional Ethernet. In this way, the network communication module 218 can include a physical interface for connection to a computer network (e.g., a mobile switching center (MSC)). The term "configured for...", "configured to..." and its word forms used herein with respect to a specified operation or function refers to a device, component, circuit, structure, machine, signal, etc. that is physically constructed, programmed, formatted and / or arranged to perform a specified operation or function.

[0040] The Open Systems Interconnection (OSI) model (referred to herein as the "Open Systems Interconnection Model") is a concept and logical layout that defines that network communications used by a system (e.g., a wireless communication device, a wireless communication node) are open to interconnection and communication with other systems. The model is decomposed into seven subcomponents or layers, each of which represents a conceptual set of services provided to the layers above and below it. The OSI model also defines a logical network and effectively describes computer packet delivery using different layer protocols. The OSI model may also be referred to as a seven-layer OSI model or a seven-layer model. In some embodiments, the first layer may be a physical layer. In some embodiments, the second layer may be a medium access control (MAC) layer. In some embodiments, the third layer may be a radio link control (RLC) layer. In some embodiments, the fourth layer may be a packet data convergence protocol (PDCP) layer. In some embodiments, the fifth layer may be a radio resource control (RRC) layer. In some embodiments, the sixth layer may be a non-access stratum (NAS) layer or an Internet Protocol (IP) layer, and the seventh layer is another layer.

[0041] Various example embodiments of the present solution are described below with reference to the accompanying drawings to enable a person of ordinary skill in the art to make and use the present solution. It will be apparent to a person of ordinary skill in the art that, after reading this disclosure, various changes or modifications may be made to the examples described herein without departing from the scope of the present solution. Therefore, the present solution is not limited to the example embodiments and applications described and illustrated herein. In addition, the specific order and / or hierarchy of steps in the methods disclosed herein are merely example approaches. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while remaining within the scope of the present solution. Therefore, it will be understood by a person of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in a sample order, and unless otherwise expressly stated, the present solution is not limited to the specific order or hierarchy presented. II. Systems for signal transmission Integrated Method

[0042] In 5G NR, during micro-sleep TX (transmit, transmit, or transmitter) in low traffic load scenarios, there are some always-on signals that may consume power even if they are transmitted with a long periodicity (e.g., a maximum periodicity of 160 milliseconds (ms)). Depending on the actual implementation, most transmissions are unnecessary. Therefore, a solution for enhanced signal transmission is needed to achieve lower power consumption.

[0043] Currently, 5G devices have been deployed significantly so that coverage will be provided by 5G carrier frequencies only for DL ​​(downlink) and UL (uplink). It can be observed that the UL coverage of 5G is less than that of 4G systems because the UL carrier frequency of 5G is different from that of 4G. Efficient UL transmission enhancement can also achieve potential energy savings, so there is also a need to provide solutions for UL coverage enhancement.

[0044] Switching to sleep mode or shutting down some RF components when not needed is an effective way to reduce network power consumption. For example, if there is no UE access, the carrier can be deactivated. When the traffic load is low, the number of Tx / Rx antennas can be reduced.

[0045] However, there are some problems with this energy-saving method. First, there are some common signals and necessary transmissions in NR, such as SSB (synchronization signal block), SIB1 (system information block), paging, and PRACH (physical random access channel) reception. Therefore, the network cannot easily enter a low-power state, such as sleep mode. Secondly, even if the device can enter the sleep state, waking up the device is also a problem. If a semi-static configuration is used, the device can only be awakened after sleeping for a period of time. If there is a service demand in the sleep state, it cannot be met, which will cause a lot of delay and affect the user experience.

[0046] In summary, in order to reduce the power consumption of the communication system, the network should be able to enter a low power state for as long as possible. In addition, a more dynamic wake-up mechanism should be introduced to meet flexible service requirements and minimize the impact on user experience. Obviously, the UE can participate in this process to achieve better results.

[0047] A solution to the impact of DL (downlink) signals on UL (uplink) random access procedures is disclosed to ensure UE initial access performance and network energy saving without increasing UE power and degrading UE experience. In particular, the embodiments described herein allow a base station to control the number and timing of random access (RA) opportunities (ROs) and signal such information to the UE. From the UE side, knowing the available or valid ROs allows them to manage or use sleep mode or low power mode more efficiently. In addition, when the timing of available or valid ROs is known, the UE can perform initial access more reliably.

[0048] As used herein, "comprising" in a claim, such as "or" used in a list of items (e.g., a list of items beginning with a phrase such as "at least one of..." or "one or more of...") indicates an inclusive list, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an exemplary step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on".

[0049] In the present disclosure, a base station (BS) may mean a communication node, or a BTS (base transceiver station) in 2G, or a NodeB in 3G, or an eNB (E-UTRAN NodeB / enhanced NodeB) in 4G, or a gNB in ​​5G, or a base station of LTE (Long Term Evolution) or NR (New Air Interface Access Technology), or a base station of a next generation communication system, or a cell having a normal state or an activated state or a deactivated state or a dormant state, or a cell providing basic coverage, or a cell providing enhanced capacity, or a small cell, or a primary cell, or a secondary cell.

[0050] SSB represents a DL signal with a transmission mechanism that is new to NR Release 17, or an enhanced DL signal based on an existing DL signal in NR Release 17. SSB also includes or means at least one of the following: a reduced number of SSBs during an SSB periodicity, an SSB periodicity greater than the maximum value of the SSB periodicity in NR Release 17, a small SSB that occupies less time and frequency domain resources than a normal SSB in NR Release 17, or an SSB with a larger periodicity configuration from a normal SSB in NR Release 17, or PSS or SSS, TRS, CSI-RS, CD-SSB, NCD-SSB (non-cell defined SSB), an inter-band SCell without SSB.

[0051] As used herein, a new SSB for an SSB in NR Release 17 includes at least one of: a small SSB that occupies less time and frequency domain resources in size than a normal SSB in NR Release 17 compared to an SSB defined in NR Release 17, or an SSB that has a greater periodicity than an SSB in NR Release 17. The greater periodicity may be an integer equal to 2β×10ms, where β may be greater than 4.

[0052] Reference now Figure 3 , a flow chart of an example signal transmission method 300 performed by a user equipment or a wireless communication device 104 or 204 according to some embodiments of the present disclosure is shown. The wireless communication device 104 or 204 may receive first information in signaling from the wireless communication node 102 or 202, the first information indicating a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission. The wireless communication device 104 or 204 may transmit a PRACH signal corresponding to a DL signal index to the wireless communication node 102 or 202 in a random access (RA) opportunity determined by the mode.

[0053] Reference now Figure 4 , a flow chart of an example signal reception method 400 performed by a wireless communication node 102 or 202 according to some embodiments of the present disclosure is shown. The wireless communication node 102 or 202 may transmit first information in signaling to a wireless communication device 104 or 204, the first information indicating first information of a pattern of at least one physical random access channel (PRACH) or downlink (DL) signal transmission. The wireless communication node may receive a PRACH signal corresponding to a DL signal index from the wireless communication device 104 or 204 in a random access (RA) opportunity determined by the pattern. Method 400 may be viewed as similar to method 300, but performed by the wireless communication node 102 or 202.

[0054] Methods 300 and 400 are described in more detail in conjunction with the following discussions of (1) patterns of availability of RA opportunities, (2) mapping relationships from SSB to availability of RA opportunities, (3) mapping relationships from SSB to preamble codes for RA, and (4) UE characteristics related to availability of RA opportunities.

[0055] Determine the availability or effectiveness of RA timing

[0056] One issue is how to determine the availability or validity of RA opportunities for transmission of PRACH signals or other UL signals. Available or valid RA opportunities for transmission of PRACH signals or other UL signals may follow a predefined or specified pattern. As used herein, the availability or validity of RA opportunities implies that RA opportunities can be used by the wireless communication device 104 or 204 to transmit PRACH or other uplink signals.

[0057] The pattern of availability or effectiveness of RA opportunities may be defined or determined according to at least one of the following.

[0058] ① Paging occasion information: The UE may assume that multiple RA occasions associated with the paging occasion are available. The number of RA occasions may be equal to n. For example, the UE 104 or 204 may assume that the RA occasions located or occurring after the paging occasions are available for the transmission of PRACH signals or other UL signals. The UE 104 or 204 may assume that the RA occasions not located after the paging occasions are not available for the transmission of PRACH signals or other UL signals. According to another example, the UE 104 or 204 may assume that the RA occasions located or occurring before the paging occasions are available. The UE 104 or 204 may assume that the RA occasions not located before the paging occasions are not available for the transmission of PRACH signals or other UL signals.

[0059] Figure 5 An example scenario is shown in which n RA occasions (RO) occurring before a paging occasion (PO) may be used for transmission of a PRACH signal or other UL signal. Figure 6 An example scenario is shown in which n ROs occurring after a paging occasion are available for transmission of a PRACH signal or other UL signal. ROs shown in solid lines represent available or valid ROs, while ROs shown in dashed lines represent unavailable or invalid ROs.

[0060] ② SSB information: UE 104 or 204 may assume that multiple RA opportunities associated with multiple SSBs are available for PRACH signal (or other UL signal) transmission. Multiple SSBs may be located before a paging opportunity. Multiple RA opportunities may be located after a paging opportunity.

[0061] The UE 104 or 204 may assume that multiple RA opportunities associated with multiple SSBs located before the paging opportunity are available for PRACH signal (or other UL signal) transmission, and that the multiple RA opportunities are located after the paging opportunity. The UE 104 or 204 may assume that RA opportunities not associated with multiple SSBs located before the paging opportunity are not available for PRACH signal (e.g., RA preamble) or other UL signal transmission, even if the RA opportunity is located after the paging opportunity.

[0062] Figure 7 An example scenario is shown in which multiple ROs associated with four SSBs located before the PO are available or valid for PRACH signaling or other uplink signaling transmission. The four SSBs are located before the PO, and n ROs associated with the four SSBs (shown in solid lines) are located after the PO. The ROs shown in dashed lines are not associated with any of the four SSBs and, therefore, are not available or valid for PRACH signaling transmission.

[0063] Figure 8 A scenario is shown in which multiple ROs associated with three SSBs located before the PO are available or valid for PRACH signal transmission according to some embodiments of the present disclosure. The relevant SSBs with respect to the availability or validity of the RO are the three SSBs shown in solid lines. There are n ROs associated with the three SSBs and are available or valid for PRACH signal transmission. The SSB is located before the PO, and the n ROs associated with the three SSBs (shown in solid lines) are located after the PO. The RO shown in dotted lines is not associated with any SSB of the three SSBs and is therefore unavailable or invalid for PRACH signal transmission.

[0064] In some embodiments, paging occasion (PO) information or SSB information for determining the availability of RA opportunities is indicated or used for idle mode UEs.

[0065] ③ Multiple RA opportunities: The UE 104 or 204 may assume that multiple RA opportunities occurring or located during a specific resource are available or valid for PRACH signal or RA preamble transmission. The specific resource may be defined by a PRACH transmission parameter for PRACH transmission, which includes a PRACH preamble format, time resources, and frequency resources.

[0066] ④PRACH configuration period: The UE may assume that the multiple RA opportunities available or valid for PRACH signal (or RA preamble) transmission are determined by the PRACH configuration period. For example, in some embodiments, the PRACH configuration period is not greater than 320ms or not less than 10ms.

[0067] According to a first example, the maximum value of the PRACH configuration period may be greater than 160 ms, for example, for the case where the SCS configuration for FR1=15 KHz or the SCS configuration for FR2=60 KHz,

[0068] In some embodiments of the first example, the maximum value of the PRACH configuration index configured by higher layer signaling is not less than M (e.g., 262) and not greater than M+α*n, where n is the number of PRACH configuration periods greater than 160 ms. M may be an integer in the range of 0 to 262. Parameter α may be any value in the range of 1 to 11. The value of the PRACH configuration period greater than 160 ms may be configured for FR1. The value of the PRACH configuration period greater than 160 ms may be configured for at least one of the following preamble formats: 0, 1, 2, 3, A1, A2, A3, B4, C0, or C2. The value of the PRACH configuration period greater than 160 ms may be 320 ms or may include 320 ms, and the maximum value of the PRACH configuration index configured by higher layer parameters may be a value in the range of 263 to 273.

[0069] In some embodiments of the first example, the maximum value of the PRACH configuration index configured by higher layer signaling is not less than M (e.g., 255) and not greater than M+α*n, where n is the number of PRACH configuration periods greater than 160 ms. M may be an integer in the range of 0 to 255. Parameter α may be any value in the range of 1 to 19. The value of the PRACH configuration period greater than 160 ms may be configured for FR2. The value of the PRACH configuration period greater than 160 ms may be configured for at least one of the following preamble formats: A1, A2, A3, B1, B4, C0 or C2, A1 / B1, A2 / B2 or A3 / B3. The value of the PRACH configuration period greater than 160 ms may be 320 ms or may include 320 ms, and the maximum value of the PRACH configuration index configured by higher layer parameters may be a value in the range of 255 to 274.

[0070] ⑤ Association period: An association period is or represents a (configured) plurality of PRACH configuration periods. The duration of an association period is the PRACH configuration period multiplied by the number of PRACH configuration periods in the association period. The value of the configured association period (or the unit of the association period) represents the number of PRACH configuration periods within the association period, for example, 1, 2, 4, 8, 16. The maximum duration of the association period may be a constant value (for example, 160ms) so that the association period is determined (or limited) by the value of the PRACH configuration period. The value of the association period may be determined by dividing the maximum duration of the association period by the PRACH configuration period. The association period starting from frame 0 for mapping the SSB index to the PRACH opportunity is the minimum value in the set determined by the PRACH configuration period.

[0071] According to a first example, for the case of PRACH configuration period=x, the number of PRACH configuration periods during the association period is at least one of the integers in the predefined set, where the integers in the predefined set are not less than n1 and not greater than n2. The value x in ms may be an integer not less than min_x and not greater than max_x, where min_x is not greater than 10 or max_x is not less than 160. In some embodiments, n1 is not greater than 1, and n2 is not less than For example, max_x can be an integer and equal to 2 β *10ms, where β is greater than 4.

[0072] In some embodiments, max_x=320ms, min_x=10ms, for PRACH configuration period=10ms, the candidate value of the association period may be at least one of 1, 2, 4, 8, 16 or 32. n1=1, n2=32. In some embodiments, max_x=640ms, min_x=10ms, for PRACH configuration period=20ms, the candidate value of the association period may be at least one of 1, 2, 4, 8, 16 or 32. n1=1, n2=64. In some embodiments, max_x=1280ms, min_x=10ms, for PRACH configuration period=40ms, the candidate value of the association period may be at least one of 1, 2, 4, 8, 16 or 32. n1=1, n2=128. In some embodiments, max_x = 2560ms, min_x = 10ms, for PRACH configuration period = 80ms, the candidate value of the associated period can be at least one of 1, 2, 4, 8, 16 or 32. n1 = 1, n2 = 256. In some embodiments, max_x = 640ms, min_x = 320ms, for PRACH configuration period

[0073] =320ms, the candidate value of the association period may be 1 or 2. n1=1, n2=2. In some implementations, max_x=640ms, min_x=320ms, for a PRACH configuration period=640ms, the candidate value of the association period may be at least 1. n1=1, n2=2.

[0074] ⑥ Association pattern period: The association pattern period may include one or more association periods and may be determined so that the pattern between the PRACH opportunity and the SSB index is repeated at most every max_x or min_x*n2. PRACH opportunities that are not associated with SSB indices after an integer number of association periods are not used for PRACH transmission.

[0075] ⑦ Validity duration for multiple RACH opportunities: The UE may assume that one or more RA opportunities during the validity duration are valid or may be used for PRACH transmission.

[0076] ⑧ Multiple (configured) valid / available PRACH configuration periods: The UE 104 or 204 may assume that one or more RA opportunities during or within a configured multiple valid or available PRACH configuration periods may be used for PRACH transmission.

[0077] ⑨ Duration for multiple valid or available PRACH configuration periods (configured): The UE 104 or 204 may assume that one or more RA opportunities within a PRACH configuration period during the duration may be used for PRACH transmission.

[0078] ⑩ Multiple available association periods: The UE 104 or 204 may assume that one or more RA opportunities during multiple association periods with availability may be used for PRACH transmission.

[0079] Duration for multiple association periods with availability : The UE 104 or 204 may assume that one or more RA opportunities during the association period (or during a configured or predefined duration) may be used for PRACH transmission.

[0080] Offset: The UE 104 or 204 may assume that one or more RA opportunities located after the starting position determined by the offset are available or valid for PRACH signal transmission.

[0081] Starting position of duration of RACH opportunity: The UE 104 or 204 may assume that one or more RA opportunities after the starting position are available or valid for PRACH signal transmission. In some examples, the UE 104 or 204 may assume that one or more RA opportunities after the starting position are available. The starting position may be determined by at least one of: the position / SFN / time slot index of the paging opportunity, the paging cycle / eDRX cycle in which the paging opportunity is located, the number of SSBs, the first RA opportunity mapped to the number of SSBs after the paging opportunity, the duration, the offset, or a SIB or DCI carrying indication information associated with the pattern of availability of one or more RA opportunities.

[0082] The wireless communication node (or base station) 102 or 202 may send indication information for the availability or validity of RA opportunities to the wireless communication device (or UE) 104 or 204. The indication information may indicate to the UE 104 or 204 how to identify RA opportunities that are available or valid for PRACH signal transmission. The indication information sent by the base station 102 or 202 and received by the UE 104 or 204 may include ① to At least one of .

[0083] Triggering or signaling an indication of available or valid RA opportunities may be implemented in various ways. Indication information related to the availability (validity) of RA opportunities for PRACH transmission may be indicated by at least one of the following signaling:

[0084] a. Cell-specific DCI: DCI that carries information about all UEs in a cell can be used to indicate or signal to the UE the availability of RACH opportunities for PRACH transmission. The CRC of the cell-specific DCI is scrambled by P-RNTI, SI-RNTI, TC-RNTI or RA-RNTI:

[0085] a) The information field can be designed according to at least one of the following methods:

[0086] i. One information block in the DCI may be configured (e.g., by the base station 102 or 202) for the availability of RACH opportunities indicated by PRACH transmission for a cell or cell group. The number of blocks may be no greater than the number of cells or cell groups configured by higher layer parameters, or may be equal to 1. The starting position of the block may be determined by parameters configured by higher layers for one or more cells or cell groups.

[0087] ii. The bitmap field in the DCI may be configured for the availability of RACH opportunities for PRACH transmission indication for one or more cells or cell groups. If the higher layer parameters associated with the availability of RACH opportunities for PRACH transmission are not configured, the bit width of the bitmap field may be 0 bits, otherwise a bitmap of N bits is determined according to the number of cells or cell groups provided by the higher layer parameters. Each bit may correspond to a cell or a cell group configured by the higher layer parameters.

[0088] iii. An indication field in the DCI may be configured for the availability of RACH opportunities for PRACH transmission indication in the cell.

[0089] b) A group of cells may be configured by the base station 102 or 202. Cells supporting the same eDRX parameters or default paging cycle or DRX cycle may be configured in the cell group. The cell may be an SCell, an activated SCell, a dormant SCell, or a PCell.

[0090] The UE 104 or 204 may assume that the SCS configuration for PRACH transmissions in valid RACH opportunities is the same for a group of cells.

[0091] b. Group common DCI: DCI format 2_7 with CRC scrambled by RNTI, or DCI format 1_0 with CRC scrambled by P-RNTI, or DCI format 2_6 with CRC scrambled by PS-RNTI, or DCI format 2-0, 2-1, 2-2, 2-3, 2-4, 2-5, or a new DCI format for Release 17 DCI format can be used to carry indication information of the availability of RACH opportunities for PRACH transmission. The field of the indication information can be designed according to at least one of the following:

[0092] a) If an existing Release 17 DCI format is used to indicate indication information associated with availability of RACH opportunities for PRACH transmission, or higher layer parameters associated with PRACH transmission are configured for the UEs of the group, an existing information field or a new information field is used to indicate information associated with availability of RACH opportunities for PRACH transmission. The existing field may include at least one of the following:

[0093] i. 'Slot format indicator' in DCI format 2_0 with CRC scrambled by SFI-RNTI or available RB set indicator or COT duration indicator or search space set group switching flag;

[0094] ii. pre-emption indication in DCI format 2_1 with CRC scrambled by INT-RNTI;

[0095] iii. Fields in DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI or TPC-PUCCH-RNTI, or DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI, or DCI format 2_4 with CRC scrambled by CI-RNTI, or DCI format 2_5 with CRC scrambled by AI-RNTI;

[0096] iv. A field of 'Wake-up indication' or 'SCell dormancy indication' in a block in DCI format 2_6 scrambled by PS-RNTI;

[0097] v. Paging indication field or TRS availability indication in DCI format 2_7 scrambled by PEI-RNTI.

[0098] b) The UE group may be determined or defined based on at least one of the following:

[0099] i. The UE entities of the UEs in the group are configured by higher layer parameters;

[0100] ii. Multiple UE groups are configured by higher layer parameters;

[0101] iii. UEs with valid PO in the same PF or multiple sequential PFs during an eDRX cycle or a default paging cycle are configured as a UE group.

[0102] c) The information field in the DCI may indicate one or more UEs according to at least one of the following procedures:

[0103] i. One information block in DCI is configured for UEs in a UE group.

[0104] ii. One information block in DCI is configured for a group of UEs.

[0105] iii. The bits in the bitmap in the DCI are configured for one or more groups of UEs.

[0106] c. UE-specific DCI: the existing DCI format 0-1 or DCI format 0-2, or DCI format 1-1 or DCI format 1-2, or a new DCI may be used to carry the indication information of the availability of RACH opportunities for PRACH transmission.

[0107] a) An indication field in the DCI may be configured for the availability of RACH opportunities for PRACH transmission indication to the UE.

[0108] i. The indication field is a bitmap to indicate the availability of one or more validity durations or periodicities of the availability of RACH opportunities for PRACH transmission;

[0109] ii. The indication field may be an n-bit field to indicate the reference point or starting SFN / time slot / symbol for the validity duration of PRACH transmission or the availability of RACH opportunities;

[0110] b) An existing information field may be used to indicate information related to the availability of RACH opportunities for PRACH transmission. The existing information field may include at least one of the following:

[0111] i. the 'Frequency domain resource assignment', 'Time domain resource assignment', 'Modulation and coding scheme', 'New data indicator', 'Redundancy version', 'HARQ process number' or 'UL / SUL indicator' field in DCI format 0_0 with CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI;

[0112] ii. 'HARQ-ACK bitmap' or 'all remaining bits' used to indicate CG-DFI in DCI format 0_1 ​​with CRC scrambled by C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI, 'frequency domain resource allocation', 'time domain resource allocation', 'modulation and coding scheme', 'new data indicator', 'redundancy version', 'HARQ process number' or 'UL / SUL indicator';

[0113] iii. 'Frequency domain resource allocation', 'Time domain resource allocation', 'Modulation and coding scheme', 'New data indicator', 'Redundancy version', 'HARQ process number' or 'UL / SUL indicator' in DCI format 0_2 with CRC scrambled by C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI;

[0114] iv. 'Random access preamble index', 'UL / SUL indicator', 'SS / PBCH index', 'PRACH mask index', 'Reserved bits', 'Time domain resource allocation', 'Modulation and coding scheme', 'New data indicator', 'Redundancy version', 'HARQ process number', 'Downlink allocation index', 'PUCCH resource indicator', 'Short message' or 'TRS availability indication' in DCI format 1_0 with CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI;

[0115] v. 'Frequency domain resource allocation', 'Time domain resource allocation', 'Modulation and coding scheme' for transport block 1 in DCI format 1_1 or DCI format 1_2 with CRC scrambled by C-RNTI or CS-RNTI or MCS-C-RNTI, 'New data indicator' for transport block 1, 'Redundancy version' for transport block 1, 'HARQ process number', 'PDSCH group index' or 'HARQ-ACK retransmission indicator' or 'SCell sleep indication'.

[0116] d. MAC CE: MAC CE may be used to indicate indication information, such as activation / start of availability of RACH opportunities for PRACH transmission, deactivation / stop of availability of RACH opportunities, or change of availability of RACH opportunities.

[0117] e.RRC signaling: The parameters for the availability of RACH opportunities for PRACH transmission may include at least one of the following:

[0118] a) information indicating the availability of the RACH opportunities for PRACH transmission mentioned above;

[0119] b) Availability parameters of RACH opportunities for PRACH transmission configured for a cell or a group of cells;

[0120] c) Availability parameters of RACH opportunities for PRACH transmission configured for a UE or a group of UEs.

[0121] f. SIB: If the UE is configured to support PRACH transmission, the UE shall acquire SIB information during a valid modification period.

[0122] a) The UE may assume that the modification period for SIB acquisition is the modification period n after the modification period n-1 in which the indication of SI change was received, or the modification period according to the mechanism specified in NR Release 17.

[0123] i. Wherein if the information carried by the SIB indicates the start or availability of the RACH opportunity for PRACH transmission, the availability of the RACH opportunity for PRACH transmission during the modification period n+1 is available to the UE. If the SIB acquired by the UE does not carry the indication information of the valid RACH opportunity for PRACH transmission, the UE assumes that the RACH opportunity for PRACH transmission stops or does not start or is unavailable.

[0124] b) The indication information carried by the SIB may include at least one of the following:

[0125] i.PRACH configuration index;

[0126] ii. Availability of one or more validity durations of RACH opportunities for PRACH transmission;

[0127] iii. Availability of one or more RACH opportunities;

[0128] iv. Parameters associated with RACH timing;

[0129] v. The number of RBs or OFDM symbols occupied by RACH opportunities used for PRACH transmission;

[0130] vi. The periodicity or duration of RACH opportunities for PRACH transmission;

[0131] vii. The validity duration or periodic start offset of the RACH opportunity for PRACH transmission;

[0132] viii. The starting position or reference point for the validity duration or for a valid RACH opportunity;

[0133] ix. Whether the validity period of the valid RACH opportunity for PRACH transmission is configured / started / stopped;

[0134] x. Whether the RACH timing for PRACH transmission is valid;

[0135] g. BS interaction: If the UE is configured to support availability indication of RACH opportunities, information related to PRACH transmission can be interacted or exchanged between the BS and other peer BSs or neighbor BSs. The interaction information may include at least one of the following:

[0136] a) Whether the availability of RACH opportunities for PRACH transmission is supported by the serving cell can be exchanged among wireless communication nodes through the Xn interface;

[0137] b) Whether the availability of RACH opportunities for PRACH transmission is supported by a group of UEs can be exchanged among wireless communication nodes through the Xn interface.

[0138] c) The Xn interface supports the exchange of signalling information between two NG-RAN nodes and the forwarding of PDUs to the corresponding tunnel endpoints.

[0139] h. Event: If the UE is configured with the availability of RACH opportunities for PRACH transmission, the availability of RACH opportunities for PRACH transmission is triggered by an event. The event includes at least one of the following:

[0140] a) Events related to the availability of RACH opportunities for PRACH transmission triggered by the BS side include at least one of the following:

[0141] i. The BS receives a request for availability of RACH opportunities for PRACH transmission sent by the UE.

[0142] ii. The BS receives confirmation information of the availability of RACH opportunities configured by multiple UEs for PRACH transmission, where the number of UEs is not less than 1, or greater than a threshold; the threshold is equal to a multiple of the number of idle mode UEs or connected mode UEs in the cell; where the multiple is a fraction and greater than 0.

[0143] iii. The serving cell is configured with DTX;

[0144] iv. The RSRP / RSRQ value reported by one or more UEs is lower than the threshold;

[0145] v. The load percentage is less than the threshold;

[0146] vi. The amount of DL or UL data is less than the threshold;

[0147] b) The event regarding the availability of RACH opportunities for PRACH transmission triggered by the UE side may include at least one of the following:

[0148] i. The UE reports confirmation of the availability of RACH opportunities configured for PRACH transmission;

[0149] ii. The UE's DL transmission is limited to the serving cell;

[0150] iii. The UE does not need to perform PDCCH monitoring during the duration;

[0151] iv. The measurement result based on SSB or CSI-RS or TRS or PTRS or PRS resources is less than the threshold;

[0152] v. The measurement result of RSRP / RSRQ is greater than the threshold;

[0153] vi. The associated SSB and CSI-RS resources configured by higher layer parameters are quasi co-located for the UE.

[0154] vii. The RRC configuration or reconfiguration including indication information associated with the availability of RACH opportunities for PRACH transmission includes at least one of the following:

[0155] 1. Information indicating the availability of the RACH opportunities for PRACH transmission mentioned above;

[0156] 2. Modification cycle;

[0157] 3. Serving cell ID or serving cell group ID for the availability of supported RACH opportunities for PRACH transmission.

[0158] c) A timer is introduced for the availability of RACH opportunities for PRACH transmission. When the timer expires, the availability of RACH opportunities for PRACH transmission is stopped or started.

[0159] Determine the mapping relationship from DL signal to the availability of RA opportunities:

[0160] The mapping relationship from the DL signal to the availability of RA opportunities may be determined by the UE or defined by the base station according to at least one of the following:

[0161] ① The association pattern period may include one or more association periods and may be determined so that the pattern between the PRACH opportunity and the SSB index is repeated at most every max_x or min_x*n2. The PRACH opportunity that is not associated with the SSB index after an integer number of association periods is not used for PRACH transmission.

[0162] ②If SSB T SSB The periodicity is greater than the maximum value of the associated mode period or the associated period or the PRACH configuration period, or is greater than 160ms,

[0163] 1) The association pattern period may include one or more association periods and is determined so that the pattern between the PRACH opportunity (or RO) and the SSB index is at most every T SSB Repeat. After an integer number of association periods, the PRACH opportunities not associated with the SSB index are not used for PRACH transmission; or

[0164] 2) The association pattern period may include one or more association periods and is determined so that the pattern between PRACH opportunities and SSB indices repeats at most every max_x or min_x*n2. PRACH opportunities that are not associated with SSB indices after an integer number of association periods are not used for PRACH transmission; or

[0165] 3) The association pattern period may include one or more association periods and is determined so that the pattern between PRACH opportunities and SSB indices repeats at most every 160 ms. PRACH opportunities that are not associated with SSB indices after an integer number of association periods are not used for PRACH transmission.

[0166] In some embodiments, the SSB may be an SS / PBCH block in NR Release 17, or an SSB with greater periodicity, or a smaller SSB.

[0167] ③ If the base station (BS) or UE is configured with discontinuous transmission (DTX), the PRACH opportunity associated with the SSB index is not used for PRACH transmission during the duration of the DTX state.

[0168] In some implementations, the situation where the PRACH configuration period is greater than 160 ms, or min_x or max_x is greater than 160 ms, may be triggered by at least one of the following events:

[0169] a) the wireless communication device is configured by signaling to support an SSB different from the SSB in New Radio (NR) Release 17; or

[0170] b) the wireless communication device is configured by signaling to support a release different from NR Release 17; or

[0171] c) the wireless communication device is configured to support a PRACH configuration period greater than 160 ms through signaling; or

[0172] d) the wireless communication device is configured to support the preamble format through signaling; or

[0173] e) The wireless communication device is configured to support RA type through signaling.

[0174] f) The signaling may be a higher layer parameter or UE capability.

[0175] Determine the mapping from DL signal to preamble for PRACH transmission

[0176] The mapping relationship from the DL signal to the preamble for RA may be determined or defined as described below.

[0177] The first technical problem for the mapping relationship from SSB to the preamble for RA can be disclosed as follows. Assumption:

[0178] - The total number of contention-based (CB) preambles given by totalNumberOfRA-Preambles or msgA-TotalNumberOfRA-Preambles is recorded as

[0179] - The number of SS / PBCH block indices associated with one PRACH opportunity given by SSB-per-rach-occasion configured by ssb-perRACH-OccasionAndCB-PreamblesPerSSB or msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB

[0180] - the number R of contention-based preambles per SS / PBCH block index per valid PRACH opportunity given by ssb-perRACH-OccasionAndCB-PreamblesPerSSB or CB-preambles-per-SSB configured by msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB,

[0181] - the number Q of contention-based preambles per SS / PBCH block index per valid PRACH opportunity given by CB-preambles-per-SSB configured by msgA-CB-PreamblesPerSSB-PerSharedRO,

[0182] -Number of SSB indices during the SSB periodicity SSB .

[0183] therefore, and yes The first problem is that for the number of SS / PBCH block indices associated with a PRACH opportunity In the case of , when the number of SSB indices during the SSB periodicity (e.g., 4) is dynamically indicated by DCI or L1 signaling and is less than the most recent number of SSB indices (e.g., 8), the number of CB preambles per SSB index for each valid PRACH opportunity for the reduced 4 SSB indices Not used for PRACH transmission. Therefore, if the number of CB preambles per SSB index for each valid PRACH opportunity for the reduced 4 SSB indices is The existing 4 SSB indexes that can be reused for PRACH transmission, the access probability will be improved, and energy consumption can be saved at the same time. For example, there may be 256 preambles available for RA opportunities, and 4 SSB indexes associated with the RA opportunities configured by higher layer parameters. That is, there may be 64 preambles for each SSB index for each RA opportunity. However, if the number of available SSB indexes for each RA opportunity is dynamically changed to 2, there are still 64 preambles for each SSB index for each RA opportunity, and the remaining (256-64*2) preambles are obviously wasted. However, if the number of preambles for each SSB index for each RA opportunity is changed to 128, UEs requesting initial access are less likely to conflict with each other compared to 64 preambles for each SSB index for each RA opportunity, especially when a large number of UEs request initial access in the serving cell.

[0184] The second problem is that for the number of SS / PBCH block indices associated with one PRACH opportunity In the case of SSB periodicity, when the number of SSB indices during the SSB periodicity (e.g., 16) is dynamically indicated by DCI or L1 signaling and is less than the number of most recent SSB indices (e.g., 8), the number of CB preambles per SSB index for each valid PRACH opportunity for the 8 additional SSB indices is Not allocated for PRACH transmission. It will reduce the access probability, especially when the best SSB index is one of the 8 SSB indices added based on SSB measurements made by the UE.

[0185] The solution for the mapping relationship between SSB and contention-based preamble for RA can be described as follows:

[0186] ① The number of contention-based random access preambles for each SS / PBCH block index per valid PRACH opportunity may be determined by at least one of the following methods:

[0187] 1) If the number of SSB indices during the SSB periodicity is N SSB Indicated by DCI, or greater or less than the number of most recently configured SS / PBCH block indices associated with a PRACH opportunity Then the number of contention-based preambles per SS / PBCH block index per valid PRACH opportunity is given by the function Determine, where the function (·) represents rounding up, rounding down, or rounding or retaining the original input value of ·, where N SSB and is an integer and Not less than 1.

[0188] a. Function of each valid PRACH opportunity with SSB index n (0≤n≤N SSB -1) Associated consecutive indexed contention-based preambles, indexed from the preamble or from +R to start.

[0189] b. In some embodiments, the number of most recently configured SS / PBCH block indices associated with a PRACH opportunity is the most recent configuration, or is given by the SSB-per-rach-occasion of the ssb-perRACH-OccasionAndCB-PreamblesPerSSB or msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB configurations.

[0190] 2) If the number of SSB indices during the SSB periodicity is N SSB The number of contention-based preambles per SS / PBCH block index per valid PRACH opportunity is R or Q, as indicated by the DCI, or is equal to the number of most recently configured SS / PBCH block indices associated with one PRACH opportunity.

[0191] Fig. 9 A diagram is shown showing an example mapping relationship from SSB to preamble for RA according to some embodiments of the present disclosure.

[0192] The second technical problem 2 for the mapping relationship from SSB to the preamble for RA can be described as follows:

[0193] When SSBs in NR Release 17, or small SSBs or SSBs with greater periodicity for use with NR Release 18 are configured for a UE, the selected type / category of SSBs associated with PRACH opportunities should be determined in order to remove ambiguity regarding the use of SSBs associated with PRACH opportunities between the BS and the UE.

[0194] Except for SSB in NR Release 17 for PRACH procedures, the solution for parameters associated with SSB types can be described as follows:

[0195] ① If SSB in NR Release 17 or small SSB or SSB with greater periodicity is configured for the UE, the UE may assume that:

[0196] 1) For each valid PRACH opportunity, a small SSB or an SSB with greater periodicity is selected with higher priority than an SSB in NR Release 17; or

[0197] 2) New parameters for PRACH transmissions associated with the type of selected SSB (except SSB in NR Release 17) are introduced, where:

[0198] a. For example, the new parameter indicates the number of SSBs that are new to NR Release 17 (e.g., small SSBs or SSBs with greater periodicity) associated with a valid PRACH opportunity.

[0199] b. For example, a new parameter indicates the number of contention-based random access preambles associated with SSBs that are new to SSBs in NR Release 17 per valid PRACH opportunity.

[0200] c. For example, new parameters are used to initialize the RA procedure associated with SSBs that are new to NR Release 17.

[0201] d. For example, the new parameter indicates a threshold value of SS-RSRP associated with SSB that is new to SSB in NR Release 17. In some embodiments, if SSB that is new to SSB in NR Release 17 is configured, the rsrp-threshold for the RACH procedure associated with SSB that is new to SSB in NR Release 17 is determined based on the following: if rsrp-ThresholdEnhancedSSB is configured by RRC, then rsrp-ThresholdEnhancedSSB is used as rsrp-threshold; otherwise, if rsrp-ThresholdSSB for four-step RA or msgA-RSRP-ThresholdSSB for two-step RA is configured by RRC, then rsrp-ThresholdSSB or msgA-RSRP-ThresholdSSB is used as rsrp-threshold for four-step or two-step RACH procedure, respectively; otherwise, the enhanced SSB cannot be selected for the RACH procedure.

[0202] e. In some embodiments, new parameters are used in NR Release 18; or

[0203] 3) The current RACH process should be ignored or cancelled.

[0204] a. When at least one of the following conditions is met: the cell is switching from the DTX active time to outside the DTX active time, or the cell is switching from the normal state to the ES state, and the current RACH process is in progress.

[0205] b. When at least one of the following conditions is met: the cell is switching from DTX active time to outside DTX active time, or the cell is switching from normal state to ES state, and the current RACH process is in progress, except for at least one of the following conditions:

[0206] a) PREAMBLE_TRANSMISSION_COUNTER is greater than 0; or

[0207] b) an LBT failure indication is not received from lower layers for the transmission of the random access preamble or the transmission of the MSGA RA preamble; or

[0208] c) this is the first MSGA transmission within this random access procedure; or

[0209] d) Random access preamble or MSGA RA preamble is transmitted.

[0210] c. In some embodiments, the current RACH process is performing RA preamble transmission.

[0211] 4) Once the random access preamble is transmitted, and regardless of the possible occurrence of measurement gaps, if the cell is switching from DTX active time to outside DTX active time or the cell is switching from normal state to ES state, and if the current RACH procedure is in progress, the current RACH procedure shall be ignored or canceled, except for at least one of the following conditions:

[0212] a. A contention-free random access preamble for a beam failure recovery request is transmitted by the MAC entity; or

[0213] b. while ra-ResponseWindow is running, the MAC entity is monitoring the PDCCH of the SpCell for a random access response identified by the RA-RNTI; or while msgB-ResponseWindow is running, the MAC entity is monitoring the PDCCH of the SpCell for a random access response identified by the MSGB-RNTI or C-RNTI; or

[0214] c. The ra-ResponseWindow configured in BeamFailureRecoveryConfig at the PDCCH opportunity is running; or

[0215] d. Notification of receipt of a PDCCH transmission on the search space indicated by recoverySearchSpaceId is received from lower layers on the serving cell that transmitted the preamble; or notification of receipt of a PDCCH transmission of the SpCell is received from lower layers; or

[0216] e. the ra-ResponseWindow configured in BeamFailureRecoveryConfig expires and a PDCCH transmission on the search space indicated by recoverySearchSpaceId addressed to the C-RNTI has not been received on the serving cell that transmitted the preamble; or

[0217] f. the ra-ResponseWindow configured in RACH-ConfigCommon expires and a random access response containing a random access preamble identifier matching the transmitted PREAMBLE_INDEX has not been received; or

[0218] g. A valid downlink allocation has been received on the PDCCH for the MSGB-RNTI and the received TB was successfully decoded.

[0219] Embodiments for method 1) and method 2) are disclosed as follows:

[0220] 1. The parameter ssb-perRACH-OccasionAndCB-PreamblesPerSSB or msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB is used for SSBs that are new to SSBs in NR Release 17. In the following, SSBs other than SSBs in NR Release 17 or that are new to SSBs in NR Release 17 are denoted as enhanced SS / PBCH blocks or enhanced SSBs.

[0221] a. Configured by any of the parameters No more than N SSB .

[0222] b. If configured by any of the parameters Greater than N SSB , or if Then N SSB The number of SSBs used to map to each PRACH opportunity for the RACH process, i.e., an enhanced SS / PBCH block index is mapped to The R consecutive valid PRACH opportunities are each R contention-based preambles having consecutive indices associated with enhanced SS / PBCH block indices per valid PRACH opportunity starting from preamble index 0.

[0223] c. If configured by any of the parameters Greater than N SSB , or if or if YesN SSB An integer multiple of SSB The number of SSBs used for mapping to each PRACH opportunity for the RACH process, i.e., the number of SSBs per valid PRACH opportunity with enhanced SS / PBCH block index n (0≤n≤N SSB -1) Associated consecutive indexes of contention-based preambles from the preamble index start.

[0224] d. If configured by any parameter in the parameters Greater than N SSB , or if or if Not N SSB An integer multiple of SSB The number of SSBs used as mappings to each PRACH opportunity for the RACH process, and each valid PRACH opportunity has an enhanced SS / PBCH block index n (0≤n≤N SSB -1) Associated consecutive indexes of contention-based preambles from the preamble index function Initially, the function represents rounding down, rounding up, or rounding the input value to an integer.

[0225] e. If configured by any of the parameters Greater than N SSB , or if or if Not N SSB An integer multiple of SSB The number of SSBs used as mappings to each PRACH opportunity for the RACH process, and each valid PRACH opportunity has an enhanced SS / PBCH block index n (0≤n≤N SSB -1) The associated consecutively indexed contention-based preambles start from preamble index n*R-1 or n*R or n*R+1.

[0226] f. If configured by any of the parameters Greater than N SSB , or if or if Not N SSB An integer multiple of The product of R is not greater than N SSB The number of SSBs used as mappings to each PRACH opportunity for the RACH process, and each valid PRACH opportunity has an enhanced SS / PBCH block index n (0≤n≤N SSB -1) The associated consecutively indexed contention-based preambles start from preamble index n*R-1 or n*R or n*R+1.

[0227] If any of the parameters configured by Greater than N SSB , or if or if Not N SSBIf N is an integer multiple of N, then N' is used as the number of SSBs mapped to each PRACH opportunity for the RACH process, and the R contention-based preambles with consecutive indices associated with enhanced SS / PBCH block index N (0≤n≤N'-1) for each valid PRACH opportunity are indexed from the preamble index Start. Where N' is a positive integer and is closest to and not greater than or closest to and not less than or closest to the integer value N SSB , is an integer multiple of each of these integer values.

[0228] 2. If enhanced SSB is configured, a new parameter is introduced to indicate the number of enhanced SSBs mapped to each PRACH opportunity, and the number of contention-based random access preambles mapped to each SSB is used for enhanced SSB.

[0229] a.ssb-perRACH-OccasionAndCB-PreamblesPerSSB: defines the number of SSBs mapped to each PRACH opportunity for a four-step RA type and the number of contention-based random access preambles mapped to each SSB; or if enhanced SSBs are configured and the number of enhanced SSBs is less than the number of SSBs, the defined number of SSBs mapped to each PRACH opportunity for a four-step RA type is equal to the number of enhanced SSBs, and the number of contention-based random access preambles mapped to each SSB can be used for For each enhanced SSB, or the number of contention-based random access preambles mapped to each enhanced SSB is equal to the value of the function (the number of SSBs configured by the parameter * the number of contention-based random access preambles mapped to each SSB configured by the parameter / the number of enhanced SSBs), where the function represents rounding the input value up or down or rounding to an integer; or introducing specific parameters for the enhanced SSB to define the number of enhanced SSBs mapped to each PRACH opportunity for the four-step RA type, and the number of contention-based random access preambles mapped to each enhanced SSB;

[0230] b.msgA-SSB-PerRACH-OccasionAndCB-PreamblesPerSSB: defines the number of SSBs mapped to each PRACH opportunity for a two-step RA type, and the number of contention-based random access preambles mapped to each SSB; or, if enhanced SSBs are configured, or the number of enhanced SSBs is less than the number of SSBs, or enhanced SSBs are configured for a two-step RA type, a defined number of SSBs mapped to each PRACH opportunity for a two-step RA type and a defined number of contention-based random access preambles mapped to each SSB are used for each enhanced SSB; or specific parameters are introduced for enhanced SSBs to define the number of SSBs mapped to each PRACH opportunity for a two-step RA type, and the number of contention-based random access preambles mapped to each SSB;

[0231] 3. When the random access procedure is initiated on the serving cell, the parameters for initializing the RA procedure associated with enhanced SSB shall be introduced into at least one of the following:

[0232] a. Wherein the random access procedure is initiated by a PDCCH command, by the MAC entity itself, or by RRC for events according to NR Release 17 specifications.

[0233] b.rsrp-ThresholdEnhancedSSB: RSRP threshold for selection of enhanced SSB for four-step RA type. If the random access procedure is initiated for beam failure recovery, the rsrp-ThresholdEnhancedSSB used for selection of enhanced SSB in candidateBeamRSList refers to the rsrp-ThresholdEnhancedSSB in the BeamFailureRecoveryConfig IE;

[0234] c.rsrp-ThresholdCSI-RS: RSRP threshold for selection of CSI-RS for four-step RA type. If the random access procedure is initiated for beam failure recovery, if enhanced SSB is configured, rsrp-ThresholdCSI-RS is equal to rsrp-ThresholdEnhancedSSB in BeamFailureRecoveryConfig IE, otherwise rsrp-ThresholdCSI-RS is equal to

[0235] rsrp-ThresholdSSB in BeamFailureRecoveryConfig IE;

[0236] d.msgA-RSRP-ThresholdEnhancedSSB: RSRP threshold for selection of enhanced SSB for two-step RA type;

[0237] e.rsrp-ThresholdEnhancedSSB-SUL: RSRP threshold for selection between NUL carrier and SUL carrier, if enhanced SSB is configured;

[0238] f.Offset, if enhanced SSB is configured, Offset is defined for msgA-RSRP-Threshold or rsrp-ThresholdMsg3, otherwise Offset is not configured or equal to 0;

[0239] g.candidateBeamRSList: a list of reference signals (CSI-RS and / or SSB and / or enhanced SSB) identifying candidate beams for recovery and associated random access parameters;

[0240] h.ra-ehancedSsb-OccasionMaskIndex: defines the PRACH opportunity associated with the enhanced SSB, during which the MAC entity can transmit the random access preamble;

[0241] i.msgA-CB-PreamblesPerSSB-PerSharedRO: when the PRACH opportunity is shared between the two-step RA type and the four-step RA type, the number of contention-based random access preambles for the two-step RA type mapped to each SSB is defined; or, if enhanced SSBs are configured or the number of enhanced SSBs is less than the number of SSBs, the number of contention-based random access preambles for the two-step RA type mapped to each SSB is also used to be mapped to each enhanced SSB; or, if enhanced SSBs are configured or the number of enhanced SSBs is less than the number of SSBs, when the PRACH opportunity is shared between the two-step RA type and the four-step RA type, the number of contention-based random access preambles for the two-step RA type mapped to each SSB is equal to 0; or, when the PRACH opportunity is shared between the two-step RA type and the four-step RA type, a specific parameter is introduced for enhanced SSBs to define the number of contention-based random access preambles for the two-step RA type mapped to each SSB;

[0242] j. If groupBconfigured is configured, random access preamble group B is configured for four-step RA type. If enhanced SSB is configured, among the contention-based random access preambles associated with enhanced SSB, the first numberOfRA-PreamblesGroupA included in the groupBconfigured random access preamble belongs to random access preamble group A. The remaining random access preambles associated with enhanced SSB belong to random access preamble group B (if configured).

[0243] k. If groupB-ConfiguredTwoStepRA is configured, random access preamble group B is configured for two-step RA type. If enhanced SSB is configured, among the contention-based random access preambles for two-step RA type associated with enhanced SSB, the first numberOfRA-PreamblesGroupA included in the GroupB-ConfiguredTwoStepRA random access preamble belongs to random access preamble group A. The remaining random access preambles associated with enhanced SSB belong to random access preamble group B (if configured).

[0244] 1. If random access preamble group B is supported by the cell and if enhanced SSB is configured, include random access preamble group B for each SSB or each enhanced SSB.

[0245] m. If random access preamble group B is configured for four-step RA type and if enhanced SSB is configured, numberOfRA-PreamblesGroupA: defines the number of random access preambles in random access preamble group A for each SSB or each enhanced SSB included in groupBconfigured.

[0246] n. If random access preamble group B is configured for two-step RA type and if enhanced SSB is configured, numberOfRA-PreamblesGroupA: defines the number of random access preambles in random access preamble group A for each SSB or each enhanced SSB included in GroupB-ConfiguredTwoStepRA.

[0247] o. If enhanced SSB is configured, specific parameter sets of ra-ResponseWindow, ra-ContentionResolutionTimer, msgB-ResponseWindow or ta-Report are configured by higher layers.

[0248] p. When enhanced SSB is configured or enhanced SSB is selected for the RA procedure, at least one of the following UE variables is used for the RA procedure:

[0249] a) PREAMBLE_INDEX for enhanced SSB;

[0250] b)REAMBLE_TRANSMISSION_COUNTER for enhanced SSB;

[0251] c) PREAMBLE_POWER_RAMPING_COUNTER for Enhanced SSB;

[0252] d) PREAMBLE_POWER_RAMPING_STEP for enhanced SSB;

[0253] e) PREAMBLE_RECEIVED_TARGET_POWER for enhanced SSB;

[0254] f) PREAMBLE_BACKOFF for enhanced SSB;

[0255] g) PCMAX for enhanced SSB;

[0256] h) SCALING_FACTOR_BI for enhanced SSB;

[0257] I) RA_TYPE for enhanced SSB;

[0258] j) POWER_OFFSET_2STEP_RA for enhanced SSB;

[0259] k) MSGA_PREAMBLE_POWER_RAMPING_STEP for Enhanced SSB.

[0260] q. If enhanced SSB is configured, the network shall configure the same value for rsrp-ThresholdEnhancedSSB-SUL in all BWPs. Therefore, the UE can obtain this parameter from any random access configuration.

[0261] 4. When the random access procedure is initiated on the serving cell, if enhanced SS is configured, or

[0262] a. If the BWP selected for the RA procedure is configured with two-step RA type RA resources, or if the random access procedure is initiated for reconfiguration with sync, and if contention-free random access resources for two-step RA type have been explicitly provided in the rach-ConfigDedicated of the BWP selected for the random access procedure, the MAC entity shall set RA_TYPE to two-step RA.

[0263] b. If the BWP selected for the RA procedure is configured with only four-step RA type RA resources, the MAC entity shall set RA_TYPE to four-step RA. Enhanced SSB shall not be selected for the RA procedure.

[0264] 5. If the DTX or ES state is configured, rsrp-ThresholdMsg3 is updated or adjusted based on the indication of L1 signaling, wherein the L1 signaling is also used to indicate information associated with the DTX or ES state.

[0265] 6. If contention-free random access resources have not been provided for the random access procedure, and if one or more features including enhanced SSB or DTX or ES state are applicable to the RA procedure,

[0266] a. If no random access resource set is available for the current random access procedure, the MAC entity shall select a RA resource set that is not associated with any feature indication; or

[0267] b. Otherwise, if there are one or more available random access resource sets, and one of these random access resource sets can be used to indicate all the features that trigger the random access procedure, the MAC entity shall select an available random access resource set for the random access procedure; or

[0268] c. Otherwise (i.e., there are one or more available random access resource sets that are configured with indications of a subset of all features for triggering the RACH process), the MAC entity shall select a random access resource set from the available random access resource sets based on the priority order indicated in the system information for the random access process.

[0269] 7. For each configured random access resource set for the four-step RA type and each configured random access resource set for the two-step RA type: if the feature of enhanced SSB or DTX or ES status indication is configured for the RA resource set, the MAC entity shall consider the random access resource set as unavailable for RACH procedures that are not triggered for the enhanced SSB or DTX or ES status, or if the enhanced SSB or DTX or ES status indication is not applicable.

[0270] 8. If an available random access resource set configured with enhanced SSB or DTX or ES state indication is identified, the MAC entity shall select an RA resource set from one or more RA resource sets configured with features applicable to the current RACH process, wherein one RA resource set is configured with enhanced SSB; or the RA resource set is configured with DTX; or the RA resource set is configured with the current ES state or the target ES state.

[0271] 9. If enhanced SSB is configured, the rsrp-threshold associated with the enhanced SSB for the RACH process is determined based on the following: If rsrp-ThresholdEnhancedSSB is configured by RRC, then rsrp-ThresholdEnhancedSSB is used as rsrp-threshold; otherwise, if rsrp-ThresholdSSB (for four-step RA) or msgA-RSRP-ThresholdSSB (for two-step RA) is configured by RRC, then rsrp-ThresholdSSB or msgA-RSRP-ThresholdSSB is used as rsrp-threshold for the four-step or two-step RACH process, respectively; otherwise, enhanced SSB cannot be selected for the RACH process. For example,

[0272] a. If the selected RA_TYPE is set to four-step RA, if the random access procedure is initiated for SpCell beam failure recovery; and if beamFailureRecoveryTimer is running or unconfigured; and if contention-free random access for beam failure recovery request associated with any enhanced SSB in the enhanced SSB has been explicitly provided by RRC; and if at least one of the enhanced SSBs with an SS-RSRP higher than rsrp-threshold among the enhanced SSBs in candidateBeamRSList is available, the MAC entity shall select an enhanced SSB with an SS-RSRP higher than rsrp-threshold among the enhanced SSBs in candidateBeamRSList.

[0273] b. For the four-step RACH process, if ra-PreambleIndex is not 0b000000, and if the contention-free random access resources associated with the enhanced SSB have been explicitly provided by RRC, and at least one enhanced SSB with an SS-RSRP higher than rsrp-threshold is available among the associated enhanced SSBs, the MAC entity shall select an enhanced SSB with an SS-RSRP higher than rsrp-threshold among the associated enhanced SSBs and set PREAMBLE_INDEX to the ra-PreambleIndex corresponding to the selected enhanced SSB.

[0274] c. If the contention-free two-step RA type resources associated with the enhanced SSB have been explicitly provided by higher layer parameters, and at least one enhanced SSB among the associated SSBs with an SS-RSRP higher than the rsrp-threshold is available, the MAC entity shall select an enhanced SSB with an SS-RSRP higher than the rsrp-threshold among the associated enhanced SSBs and set PREAMBLE_INDEX to the ra-PreambleIndex corresponding to the selected enhanced SSB.

[0275] 10. For the four-step RACH procedure, if ra-PreambleIndex is not 0b000000, and if enhanced SSB is configured, the MAC entity shall select the enhanced SSB signaled by the PDCCH. If the enhanced SSB is not signaled by the PDCCH, the MAC entity shall select the SSB signaled by the PDCCH.

[0276] 11. If an enhanced SSB or SSB is configured, if at least one of the enhanced SSBs with an SS-RSRP higher than rsrp-threshold and at least one of the SSBs with an SS-RSRP higher than rsrp-ThresholdSSB (for four-step RACH) or higher than msgA-RSRP-ThresholdSSB (for two-step RACH) is available, the enhanced SSB will be selected; or if at least one of the enhanced SSBs with an SS-RSRP higher than rsrp-threshold is available, the enhanced SSB with an SS-RSRP higher than rsrp-threshold will be selected; or if there is no enhanced SSB higher than rsrp-threshold and there is no SSB with an SS-RSRP higher than rsrp-ThresholdSSB (for four-step RACH) or higher than msgA-RSRP-ThresholdSSB (for two-step RACH), the MAC entity will select any SSB. For example,

[0277] a. For four-step RACH, if the random access resources for SI request have been explicitly provided by RRC, if at least one of an enhanced SSB with an SS-RSRP higher than rsrp-threshold and an SSB with an SS-RSRP higher than rsrp-ThresholdSSB is available, the MAC entity shall select the enhanced SSB with an SS-RSRP higher than rsrp-threshold.

[0278] b. For contention-based random access preamble selection, if at least one of the enhanced SSBs with SS-RSRP higher than rsrp-threshold is available, the MAC entity shall select the enhanced SSB with SS-RSRP higher than rsrp-threshold.

[0279] 12. For four-step RACH, in the association period given by ra-AssociationPeriodIndex in si-RequestPeriod, if the restrictions given by ra-enhancedSsb-OccasionMaskIndex or ra-ssb-OccasionMaskIndex (if configured) allow enhanced SSB and SSB, enhanced SSB will be selected.

[0280] 13. For two-step RACH, to determine if there is an enhanced SSB with SS-RSRP higher than msgA-RSRP-ThresholdSSB or msgA-RSRP-ThresholdEnhancedSSB, the UE uses the latest unfiltered L1-RSRP measurement.

[0281] 14. If DTX or ES state is configured, and the BWP outside the DTX active time in the serving cell or during the duration of maintaining the ES state is not associated with any SSB, SS-RSRP is performed based on the SSB associated with the BWP of another serving cell indicated by a higher layer parameter.

[0282] UE features:

[0283] The UE 104 or 204 may include features related to availability of RA opportunities. The UE 104 or 204 may include features related to supporting PRACH transmissions associated with SSBs being new in NR Release 17.

[0284] In idle and low resource utilization situations, common signal transmissions (such as SSB or SIB) occupy a large portion in the time domain. According to system-level simulations, if SSB or SIB transmissions can be limited, the BS can obtain a large amount of energy saving benefits. When SSB in NR Release 17 is configured as a new SSB, the UE can perform PRACH transmissions during valid RACH opportunities associated with SSB in NR Release 17 as a new SSB.

[0285] Although various embodiments of the present solution have been described above, it should be understood that they are presented by way of example only and not by way of limitation. Similarly, various diagrams may depict example architectures or configurations, which are provided to enable those of ordinary skill in the art to understand the example features and functions of the present solution. However, these personnel will understand that the present solution is not limited to the illustrated example architectures or configurations, but may be implemented using a variety of alternative architectures and configurations. In addition, as will be understood by those of ordinary skill in the art, one or more features of an embodiment may be combined with one or more features of another embodiment described herein. Therefore, the breadth and scope of the present disclosure should not be limited by any of the illustrative embodiments described above.

[0286] It should also be understood that any reference to an element using names such as "first," "second," etc., herein generally does not limit the quantity or order of those elements. Instead, these names may be used herein as a convenient means of distinguishing between two or more elements or element instances. Therefore, reference to a first element and a second element does not mean that only two elements can be utilized, or that the first element must precede the second element in some way.

[0287] In addition, those of ordinary skill in the art will understand that information and signals may be represented using any of a variety of different techniques and technologies. For example, data, instructions, commands, information, signals, bits, and symbols referenced in the above description may be represented by voltage, current, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0288] Those of ordinary skill in the art will also recognize that any of the various illustrative logical blocks, modules, processors, devices, circuits, methods, and functions described in conjunction with the aspects disclosed herein may be implemented by electronic hardware (e.g., digital implementation, analog implementation, or a combination of the two), firmware, various forms of programs or design codes containing instructions (for convenience, may be referred to herein as "software" or "software modules"), or any combination of these technologies. In order to clearly illustrate the interchangeability of such hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have been generally described above in terms of their functionality. Whether such functionality is implemented as hardware, firmware, or software, or a combination of these technologies, depends on the specific application and the design constraints imposed on the overall system. A skilled technician may implement the described functionality in various ways for each specific application, but such implementation decisions will not result in a departure from the scope of the present disclosure.

[0289] In addition, it will be understood by those of ordinary skill in the art that the various illustrative logic blocks, modules, devices, components and circuits described herein may be implemented or performed in an integrated circuit (IC), which may include 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 device, or any combination thereof. The logic blocks, modules and circuits may also include antennas and / or transceivers to communicate with various components within a network or within a device. The general-purpose processor may be a microprocessor, but in an alternative, the processor may be any conventional processor, controller or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, a combination of multiple microprocessors, a combination of one or more microprocessors combined with a DSP core, or a combination of any other suitable configurations to perform the functions described herein.

[0290] If implemented in software, the function can be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein can be implemented as software stored on a computer-readable medium. Computer-readable media include both computer storage media and communication media, and the communication media include any medium that can enable a computer program or code to be transferred from one place to another. The storage medium can be any available medium accessed by a computer. By way of example and not limitation, such a computer-readable medium can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, disk storage or other magnetic storage device, or any other medium that can be used to store desired program code in the form of instructions or data structures and can be accessed by a computer.

[0291] In this invention document, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the associated functions described herein. In addition, for the purpose of discussion, various modules are described as discrete modules; however, it will be apparent to one of ordinary skill in the art that two or more modules can be combined to form a single module that performs associated functions according to embodiments of the present solution.

[0292] In addition, in embodiments of the present solution, memories or other storage devices and communication components may be employed. It will be appreciated that, for clarity, the above description has described embodiments of the present solution with reference to different functional units and processors. However, it will be apparent that any suitable functional distribution between different functional units, processing logic elements, or processing domains may be used without departing from the present solution. For example, functionality described as being performed by a separate processing logic element or controller may be performed by the same processing logic element or controller. Therefore, reference to a particular functional unit is only a reference to a suitable device for providing the described functionality, rather than an indication of a strict logical or physical structure or organization.

[0293] Various modifications to the embodiments described in the present disclosure will be apparent to those skilled in the art, and the general principles defined herein may be applied to other embodiments without departing from the scope of the present disclosure. Therefore, the present disclosure is not intended to be limited to the embodiments shown herein, but should be given the broadest scope consistent with the novel features and principles disclosed herein, as set forth in the following claims.

Claims

1. A method comprising: Receiving, by a wireless communication device, first information in signaling from a wireless communication node, which indicates a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission; as well as The wireless communication device transmits a PRACH signal corresponding to a DL signal index to the wireless communication node in a random access (RA) opportunity determined by the pattern.

2. The method according to claim 1, wherein: The first information includes at least one of the following: information of at least one paging occasion, information of at least one synchronization signal block (SSB), Indication of multiple RA opportunities, Indication of PRACH configuration period, an indication of an association period, the association period comprising a plurality of configured PRACH configuration periods, Indication of the association mode period, an indication of the validity duration for multiple RACH opportunities, an indication of a number of configured valid or available PRACH configuration periods, an indication of the duration of a valid or available PRACH configuration period for a configured plurality, an indication of the duration for a number of valid or available association periods, an indication of an offset used to indicate the starting position of the RA opportunity, or An indication of a starting position of at least one of: a validity duration for a plurality of RACH opportunities, a duration for a configured plurality of valid or usable PRACH configuration periods, a duration for a plurality of valid or usable association periods, a PRACH opportunity, a PRACH configuration period, the association period, or the association mode period.

3. The method according to claim 2, wherein: At least a portion of the first information is used to determine at least one valid or available RA opportunity for transmission of the PRACH signal.

4. The method according to claim 2, wherein: The PRACH configuration period satisfies at least one of the following: The PRACH configuration period is at most max_x milliseconds (ms) or at least min_x ms in length, wherein at least one of min_x is not greater than 10 or max_x is not less than 160 is satisfied; or The maximum value of the PRACH configuration index configured by higher layer signaling is not less than M and not greater than M+α*n, where M is a positive integer and n is the number of PRACH configuration periods each of which is greater than 160 ms, and α is a value in the range of 1 to 11, and the PRACH configuration period is configured for at least one of the following preamble formats: 0, 1, 2, 3, A1, A2, A3, B4, C0, or C2; or α is a value in the range of 1 to 19, and the PRACH configuration period is configured for at least one of the following preamble formats: A1, A2, A3, B1, B4, C0 or C2, A1 / B1, A2 / B2 or A3 / B3.

5. The method according to claim 2, wherein: At least one of the following: The number of configured PRACH configuration periods is an integer not less than n1 and not greater than n2 in the defined set, The PRACH configuration period (x) in milliseconds (ms) is an integer not less than min_x and not greater than max_x, where min_x is not greater than 10 or max_x is not less than 160, or n1 is not greater than 1 and n2 is not less than 6. The method according to claim 5, wherein: The association pattern period includes one or more association periods and is determined such that the pattern between RA opportunities and SSB indices is repeated at most every: max_x or min_x*n2, or T SSB , where T SSB is the periodicity of the SSB and is greater than the maximum value of the associated mode period or the associated period or the PRACH configuration period, or is greater than 160 ms, and Among them, the PRACH opportunity that is not associated with the SSB index after an integer number of association periods is not used for PRACH transmission.

7. The method according to claim 6, wherein: The SSB includes: One or more synchronization signal and physical broadcast channels (SS / PBCH), SSB with large periodicity, or Small SSB.

8. The method according to claims 4 to 6, wherein: The situation that the PRACH configuration period is greater than 160ms, or min_x or max_x is greater than 160ms is triggered by at least one of the following events: The wireless communication device is configured to support a different SSB than the SSB in New Radio (NR) Release 17; or The wireless communication device is configured to support a release version different from NR Release 17; or The wireless communication device is configured to support a PRACH configuration period greater than 160 ms; or The wireless communication device is configured to support a preamble format; or The wireless communication device is configured to support RA type.

9. The method according to claim 1, wherein: The signaling includes at least one of the following: cell-specific downlink control information (DCI) signaling, comprising information for one or more wireless communication devices in the cell, the information being used to indicate at least one valid or available RA opportunity for transmission of the PRACH signal, a group common DCI having DCI format 2-7 with a cyclic redundancy check (CRC) scrambled by a radio network temporary identifier (RNTI), or DCI format 1_0 with a CRC scrambled by a paging RNTI (P-RNTI), or DCI format 2_6 with a CRC scrambled by a power save RNTI (PS-RNTI), or DCI format 2-0, 2-1, 2-2, 2-3, 2-4 or 2-5 or a defined DCI format to include information of the at least one valid or available RA opportunity for transmission of the PRACH signal, a wireless communication device-specific DCI having a DCI format 0-1, 0-2, 1-1 or 1-2 or a defined DCI format to include information of the at least one valid or available RA opportunity for transmission of the PRACH signal, Medium Access Control Element (MAC CE) signaling, Radio Resource Control (RRC) signaling, or System Information Block (SIB) signaling.

10. The method according to claim 1, comprising: The wireless communication device determines, based on a result of dividing the total number of RA preambles by the number of SSB indexes, a number of contention-based RA preambles for each valid RA opportunity, wherein: The number of contention-based RA preambles for each SSB index of each valid RA opportunity is: the result, or the result rounded up to the nearest integer, or the result rounded down to the nearest integer; The total number of RA preambles is indicated via downlink control information (DCI) signaling, or The total number of RA preambles is greater than or less than the number of most recently configured SSB indices associated with one RA opportunity.

11. The method according to claim 1, wherein: If SSB in New Radio (NR) Release 17 or SSB that is new to SSB in NR Release 17 is configured for the wireless communication device, the method includes: Determining, by the wireless communication device, at least one of: For each valid RA opportunity, an SSB that is new to an SSB in NR Release 17 is selected with higher priority than an SSB in NR Release 17; or At least one defined parameter for PRACH transmissions associated with SSBs that are new to SSBs in NR Release 17.

12. The method according to claim 11, wherein: The at least one defined parameter is configured to indicate a threshold value of a synchronization signal reference signal received power (SS-RSRP) associated with an SSB that is new to the SSB in NR Release 17.

13. The method according to claim 1, comprising: The wireless communication device determines the number of contention-based preambles mapped to each enhanced SSB index according to a result of dividing the total number of contention-based preambles configured by the defined parameters by the enhanced SSB index, wherein: The number of contention-based preambles mapped to each enhanced SSB index is equal to the result, the result is rounded up to the nearest integer, the result is rounded down to the nearest integer, or the result is rounded up to the nearest integer.

14. The method of claim 1, wherein: When an enhanced SSB is configured or multiple enhanced SSB indexes are configured, or an enhanced SSB is configured for a two-step RA type: a defined number of SSBs mapped to each RA opportunity for the two-step RA type and a defined number of contention-based RA preambles mapped to each SSB are used for each enhanced SSB; or The parameters of the enhanced SSB are configured to indicate the number of SSB indexes mapped to each PRACH opportunity for the two-step RA type and the number of contention-based RA preambles mapped to each SSB index.

15. The method according to claim 1, wherein: When the PRACH opportunity is shared between the two-step RA type and the four-step RA type, the parameters for enhanced SSB are configured to indicate the number of contention-based RA preambles for the two-step RA type mapped to each SSB.

16. The method according to claim 1, wherein: The wireless communication device is configured to support SSB different from SSB in New Radio (NR) Release 17.

17. A method comprising: Transmitting, by a wireless communication node to a wireless communication device, first information in signaling, the first information indicating a mode of at least one physical random access channel (PRACH) or downlink (DL) signal transmission; as well as A PRACH signal corresponding to a DL signal index is received by the wireless communication node from the wireless communication device in a random access (RA) opportunity determined by the pattern.

18. A non-transitory computer readable medium storing instructions which, when executed by at least one processor, cause the at least one processor to perform the method according to any one of claims 1 to 17.

19. An apparatus comprising: At least one processor configured to implement the method according to any one of claims 1 to 17.

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