Systems, methods, and non-transitory processor readable media for transmit power determination

Abstract

A system, method, non-transitory processor-readable medium, and apparatus used by a wireless communication device for determining transmission power for a plurality of physical random access channel (PRACH) transmissions in a group of PRACH transmissions, and transmitting, by the wireless communication device, the plurality of PRACH transmissions to a base station using the transmission power.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications and, more particularly, to systems, methods, and non-transitory processor-readable media for determining transmit power. Background Art

[0002] Currently, the first phase of standardization of the fifth generation mobile communication technology (5G) has been completed. A series of functions have been specified in the first three new radio (NR) versions (such as Rel-15, Rel-16 and Rel-17). Due to the direct impact of coverage on service quality as well as capital expenditure (CAPEX) and operating expenditure (OPEX), coverage is an important factor in the implementation of cellular communication networks. Although coverage is important for the success of NR implementation, so far, there has been no comprehensive coverage evaluation and comparison with traditional radio access technology (Radio Access Technologie, RAT) considering all NR specification details. Summary of the invention

[0003] In some arrangements, systems, methods, apparatus, and non-transitory computer-readable media are provided for determining, by a user equipment (UE), a transmission power for multiple physical random access channel (PRACH) transmissions in a PRACH transmission group, and for transmitting, by the UE, the multiple PRACH transmissions to a base station using the transmission power.

[0004] In some arrangements, systems, methods, apparatus, and non-transitory computer-readable media are provided for transmitting, by a base station to a UE, parameters used by a wireless communication device to determine a transmit power for transmitting multiple PRACH transmissions in a PRACH group, and for receiving, by the base station, multiple PRACH transmissions from the UE based on the transmit power.

[0005] The above and other aspects and embodiments thereof are described in more detail in the drawings, the description and the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Various exemplary arrangements of the present solution are described in detail below with reference to the following figures or drawings. The drawings are provided for illustrative purposes only and depict only exemplary arrangements 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.

[0007] Figure 1 is a diagram illustrating an example cellular communication network according to some arrangements.

[0008] Figure 2 Block diagrams of example base stations and example user equipment terminals are shown according to some arrangements.

[0009] Figure 3 An example scheme implemented to support initial access is shown.

[0010] Figure 4 is a flow chart illustrating an example method for determining transmit power for multiple PRACH transmissions according to various arrangements.

[0011] Figure 5 ] is a table showing example mapping relationships between preamble formats and different sets of DELTA_PREAMBLEs for multiple PRACH transmissions (including retransmissions / repetitions) and a single PRACH transmission for a PRACH attempt according to various arrangements.

[0012] Figure 6 is a table illustrating an example PREAMBLE_RECEIVED_TARGET_POWER determined based on a first counter for counting or recording a number of PRACH repetitions and a second counter for counting or recording a number of PRACH attempts according to various arrangements.

[0013] Figure 7 is a table illustrating an example PREAMBLE_RECEIVED_TARGET_POWER determined based on a first counter for counting or recording a number of PRACH repetitions and a second counter for counting or recording a number of PRACH attempts according to various arrangements.

[0014] Figure 8 is a diagram illustrating SSB-RSRP power thresholds corresponding to PRACH repetition factors according to some arrangements.

[0015] Fig. 9 is a table showing example relationships between msg3-DeltaPreamble, repetition factor for PRACH, and repetition factor for Msg3 according to some arrangements.

[0016] Fig.10 is a block diagram of a Discrete Fourier Transform Spread Orthogonal Frequency Division Multiplexing (DFT-S-OFDM) transmitter with FDSS and spectrum spreading according to some arrangements.

[0017] Fig.11 is a diagram illustrating examples of resources according to various arrangements.

[0018] Fig.12 is a diagram illustrating examples of resources according to various arrangements.

[0019] Fig.13 is a table listing possible values ​​of the spreading factor that may be configured for different values ​​of N according to various arrangements.

[0020] Fig.14 is a table listing possible values ​​of the spreading factor that may be configured for different values ​​of N according to various arrangements.

[0021] Fig.15 is a table showing an MCS index table for PUSCH with transform precoding (also known as DFT-s-OFDM PUSCH) according to various arrangements.

[0022] Fig.16 is a table showing the relationship between the MCS index and the spreading factor according to various arrangements.

[0023] Fig.17 is a table showing the relationship between the MCS index and the spreading factor according to various arrangements.

[0024] Fig.18 is a table showing the relationship between the MCS index and the spreading factor according to various arrangements.

[0025] Fig.19 It is a table of code points based on various arrangements. DETAILED DESCRIPTION

[0026] Various exemplary arrangements of the present solution are described below with reference to the accompanying drawings to enable those of ordinary skill in the art to make and use the present solution. It is obvious to those 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 exemplary arrangements and applications described and illustrated herein. In addition, the specific order or hierarchy of steps in the methods disclosed herein are merely example methods. Based on design preferences, the specific order or hierarchy of steps of the disclosed methods or processes may be rearranged while still remaining within the scope of the present solution. Therefore, it should be understood by those of ordinary skill in the art that the methods and techniques disclosed herein present various steps or actions in an example order, and that the present solution is not limited to the specific order or hierarchy presented, unless otherwise expressly stated.

[0027] Among the physical channels used during the initial access procedure and the handover procedure, the physical random access channel (PRACH) for requesting uplink allocation for sending uplink data to a base station is a potential coverage bottleneck. The arrangements disclosed herein relate to improving the coverage of the PRACH, and in particular to repeated transmissions of the PRACH. The arrangements disclosed herein relate to determining a transmission power for each PRACH repeated transmission.

[0028] Figure 1 An example wireless communication system 100 is shown that is arranged in accordance with the present disclosure. In the following discussion, the wireless communication system 100 may be any wireless network such as a cellular network or a narrowband network. The system 100 includes a base station 102 and a UE 104 that may communicate with each other via a communication link 110 (e.g., a wireless communication channel), and a cluster of cells (e.g., at least 126, 130, 132, 134, 136, 138, and 140) covering a geographic area 101. Figure 1 , base station 102 and UE 104 are shown as being located within 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 over its allocated bandwidth to provide adequate wireless coverage to its intended users.

[0029] For example, the base station 102 can operate on the allocated channel transmission bandwidth to provide sufficient coverage to the UE 104. The base station 102 and the UE 104 can communicate via a downlink radio frame 118 and an uplink radio frame 124, respectively. Each radio frame 118 / 124 can be further divided into subframes (or time slots) 120 / 127, and the subframes 120 / 127 can include data symbols 122 / 128. In the present disclosure, the base station 102 and the UE 104 are described herein as non-limiting examples of "communication nodes", which can generally practice the methods disclosed herein. According to various arrangements of the present solution, such communication nodes may be capable of wireless and / or wired communication.

[0030] Figure 2 A block diagram of an example wireless communication system 200 for sending and receiving wireless communication signals according to some arrangements 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 some arrangements, the system 200 may be used in applications such as Figure 1 The invention also provides a method for transmitting (eg, sending and receiving) data symbols in a wireless communication environment such as the wireless communication system 100 of the present invention, as described above.

[0031] System 200 generally includes a base station 202 and a UE 204. Base station 202 includes a base station transceiver module 210, a base station antenna 212, a base station processor module 214, a base station memory module 216, and a network communication module 218, each of which is coupled to and interconnected with each other as needed via a data communication bus 220. UE 204 includes a UE transceiver module 230, a UE antenna 232, a UE memory module 234, and a UE processor module 236, each of which is coupled to and interconnected with each other as needed via a data communication bus 240. Base station 202 communicates with UE 204 via a communication channel 250, which may be any wireless channel or other medium suitable for transmitting data as described herein.

[0032] System 200 may also include Figure 2 . The various illustrative blocks, modules, circuits, and processing logic described in conjunction with the arrangements disclosed herein may be implemented with 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 according to their functions. Whether such functions are implemented as hardware, firmware, or software may depend on specific applications and design constraints imposed on the entire system. Those familiar with the concepts described herein may implement such functions in an appropriate manner for each specific application, but the decisions of such implementations should not be interpreted as limiting the scope of the present disclosure.

[0033] According to some arrangements, 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 of which includes a circuit coupled to an antenna 232. A duplex switch (not shown) may alternatively couple the uplink transmitter or receiver to the uplink antenna in a time duplex manner. Similarly, according to some arrangements, the base station transceiver 210 may be referred to herein as a downlink transceiver 210, which includes an RF transmitter and an RF receiver, each of which includes a circuit coupled to an antenna 212. The downlink duplex switch may alternatively couple the downlink transmitter or receiver to the downlink antenna 212 in a time duplex manner. The operation of the two transceiver modules 210 and 230 may be coordinated in time so that while the downlink transmitter is coupled to the downlink antenna 212, the uplink receiver circuit is coupled to the uplink antenna 232 to receive transmissions over the wireless transmission link 250. In some arrangements, there is tight time synchronization with minimal guard times between changes in duplex direction.

[0034] 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 arrangements, the UE transceiver 210 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 related protocols in application. Instead, the UE transceiver 230 and the base station transceiver 210 can be configured to support alternative or other wireless data communication protocols, including future standards or variants thereof.

[0035] According to various arrangements, the base station 402 may be, for example, a gNB, an evolved node (eNB), a serving eNB, a target eNB, a femto station, or a micro station. In some arrangements, the 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, a laptop computer, a wearable computing device, and the like. The 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 designed to perform the functions described herein. In this manner, the processor may be implemented as a microprocessor, a controller, a microcontroller, a state machine, and 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, a combination of one or more microprocessors and a digital signal processor core, or any other such configuration.

[0036] In addition, the methods or algorithms described in conjunction with the arrangements disclosed herein may be directly embodied in hardware, firmware, software modules executed by the processor modules 214 and 236, respectively, or any practical combination thereof. The 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, the memory modules 216 and 234 may be coupled to the processor modules 210 and 230, respectively, so that the processor modules 210 and 230 may read information from and write information to the memory modules 216 and 234, respectively. The memory modules 216 and 234 may also be integrated into their respective processor modules 210 and 230. In some arrangements, the memory modules 216 and 234 may each include a cache memory for storing temporary variables or other intermediate information during the execution of instructions to be executed by the 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.

[0037] The network communication module 218 generally represents the hardware, software, firmware, processing logic and / or other components of the base station 202 that enable bidirectional communication between the base station transceiver 210 and other network components and communication nodes 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 non-limiting typical deployment, the network communication module 218 provides an 802.3 Ethernet interface so that the base station transceiver 210 can communicate with a traditional Ethernet-based computer network. In this way, the network communication module 218 can include a physical interface for connecting to a computer network (e.g., a mobile switching center (MSC)). The terms "configured for", "configured to" and variations thereof as used herein with respect to a particular operation or function refer to a device, component, circuit, structure, machine, signal, etc., which is physically constructed, programmed, formatted and / or arranged to perform a specified operation or function.

[0038] In some examples, Figure 3 An example scheme 300 is shown that is implemented for supporting initial access (eg, PRACH procedure) in a frequency range FR1 (eg, below 6 GHz band) and a frequency range FR2 (eg, above 6 GHz band). Figure 3300 , base station communication 301 (e.g., beamforming) of a base station (e.g., base station 102, base station 202) can be shown on the top track, and UE communication 302 (e.g., beamforming) of a UE (e.g., UE 104, UE 204) can be shown on the bottom track. The transmission of PRACH can be transmitted, for example, via Msg1 310. The scheme 300 also includes different PRACH formats, PRACH resource configurations, the relationship between synchronization signal / physical broadcast channel (PBCH) blocks (SSBs) and PRACH opportunities, a mechanism for PRACH retransmission, a mechanism for PRACH power control, and the like.

[0039] Figure 3 The shaded beams in the figure are the beams used to transmit or receive data. Figure 3As shown, the UE transmits a preamble in a PRACH opportunity (RO) according to the configuration of the PRACH transmission and the selected SSB. When transmitting the preamble in the RO, if the transmission-reception correspondence on the UE side can be guaranteed, a fixed mapping between the UE's receive (Rx) beam and the UE's transmit (Tx) beam can be used. A unique Tx beam can be determined based on its reception of the SSB. For example, the UE may try to use different Rx beams 303 to receive the SSB from the base station (for example, at 305), and determine the best Rx beam 304. In some arrangements, the best Rx beam 304 (for example, the best downlink Rx beam) is the beam with the highest reference signal received power (RSRP). Based on the best Rx beam 304, the best Tx beam 306 (for example, the best uplink Tx beam) is determined based on the beam correspondence. The RO used for transmitting the PRACH is determined based on the relationship between the SSB and the PRACH opportunity. Based on this relationship, the base station can determine the SSB selected by the UE. The same beam 315 can be used to transmit subsequent downlink transmissions (including Msg2320 (which can also be called Random Access Response (RAR) and Msg4340). According to the RACH process, the RAR (e.g., Msg2320) is transmitted after the PRACH transmission (e.g., Msg1 310) ends. The RAR window starts at the first symbol of the earliest control resource set (Control Resource Set, CORESET), for which the UE is configured to receive the Physical Downlink Control Channel (Physical Downlink Control Channel, PDCCH) for the Type1-PDCCH Common Search Space (CSS) set, that is, at least a predefined number of time units (e.g., symbols) after the last symbol of the PRACH opportunity corresponding to the PRACH transmission.

[0040] In an example where the UE transmits a PRACH and fails to receive a corresponding RAR within the RAR window, the UE considers that the RACH procedure has failed. In response to the failure, the UE re-initiates the RACH procedure. That is, the UE retransmits the preamble at a higher transmission power to increase the subsequent access success rate of the RACH procedure.

[0041] For PRACH transmission without repetition, the transmission power P on the activated uplink (UL) bandwidth part (BWP) b of carrier f of serving cell C is PRACH，b，f，c (i) Use the following formula to determine:

[0042] P PRACH，b，f，c (i) = min{P CMAX，f，c (i), P PRACH，target，f，c +PL b，f，c}[dBm] (1), where P CMAX，f，c (i) The maximum output power configured by the UE for carrier f of serving cell C during transmission opportunity i, P PRACH，target，f，c is the PRACH target received power (e.g., PREAMBLE_RECEIVED_TARGET_POWER, also known as the determined preamble received target power) provided by the higher layer for the activated UL BWPb of carrier f of serving cell C, and PL b，f，c is the path of the activated ULBWP b of carrier f calculated by the UE based on the DL RS associated with the PRACH transmission on the activated DL BWP of serving cell C. In some examples, PREAMBLE_RECEIVED_TARGET_POWER is set to:

[0043] preambleReceivedTargetPower+DELTA_PREAMBLE+

[0044] (PREAMBLE_POWER_RAMPING_COUNTER–1)×PREAMBLE_POWER_RAMPING_STEP+POWER_OFFSET_2STEP_RA(2),

[0045] Among them, preambleReceivedTargetPower (called the configured preamble receive target power) is the preamble receive target power configured by the base station via RRC signaling. DELTA_PREAMBLE is a value corresponding to different preamble formats. PREAMBLE_POWER_RAMPING_COUNTER is a counter that records the number of PRACH transmissions. PREAMBLE_POWER_RAMPING_STEP is the power increase for each retransmission configured by the base station via RRC signaling. For example, the value of PREAMBLE_POWER_RAMPING_STEP can be configured to 3dB, the power of the first PRACH transmission is NdBm, and the power of the first retransmission of PRACH (or the second PRACH transmission) can be N+3dB. POWER_OFFSET_2STEP_RA is used for 2-step RACH transmission, and its value is 0 under the 4-step RACH process.

[0046] A PRACH transmission including at least one repetition may also be referred to as multiple PRACH transmissions or PRACH repetitions. In some examples, multiple PRACH transmissions may be referred to as PRACH attempts or PRACH transmission groups. Multiple PRACH transmissions in a PRACH attempt or a PRACH transmission group are transmissions for a single PRACH process, which may be determined to be successful or failed. The number of PRACH transmissions within a PRACH attempt or a PRACH transmission group is referred to as a PRACH repetition factor. For example, the PRACH repetition factor may be configured by the base station to be 2, 4, or 8, indicating that a PRACH attempt or a PRACH transmission group includes 2, 4, or 8 PRACH transmissions or PRACH transmission instances, for example, 2, 4, or 8 PRACH repetitions.

[0047] The arrangements disclosed herein involve determining a transmission power for each PRACH repetition transmission and determining a relationship between the transmission power for a PRACH transmission having at least one repetition and the transmission power for a Msg.3 transmission.

[0048] Figure 4 is a flow chart illustrating an example method for determining transmit power for multiple PRACH transmissions according to various arrangements. According to various arrangements, the method may be performed by a base station 102 and a UE 104.

[0049] At 420, the UE 104 determines a transmission power for the plurality of PRACH transmissions. In some examples, at 410, the base station 102 sends to the UE at least one parameter used by the UE to determine the transmission power for the plurality of PRACH transmissions. At 420, the UE 104 may receive the at least one parameter and use it together with one or more other parameters to determine the transmission power. Transmission Power At 420, the transmission power may be determined according to any suitable method (e.g., those methods shown in (1)-(10)). In some examples, the UE 102 may determine the transmission power without using any parameters received from the base station 102. The at least one parameter includes any indication, value, or parameter sent by the base station 102 to the UE 104 as described herein.

[0050] At 430, the UE 104 transmits a plurality of PRACH transmissions using the determined transmission power to the base station 102. At 440, the base station 102 receives the plurality of PRACH transmissions from the UE 104. In some arrangements, the plurality of PRACH transmissions include an initial PRACH transmission and at least one repetition or at least one retransmission of the initial PRACH transmission in the same PRACH transmission group.

[0051] In some arrangements, the base station may configure a configured PRACH target receive power for multiple PRACH transmissions and send a parameter to the UE indicating the configured PRACH target receive power configured for multiple PRACH transmissions (with at least one repetition or retransmission) in a PRACH transmission group. For example, the parameter (e.g., preambleReceivedTargetPower) may be configured for multiple PRACH transmissions via RRC signaling. In addition, the parameter is independent of the configured PRACH target receive power for a single PRACH transmission (e.g., a PRACH transmission without repetitions) and is different from the configured PRACH target receive power for a single PRACH transmission (e.g., a PRACH transmission without repetitions). In other words, there are two parameters for indicating the configured PRACH target receive power for multiple PRACH transmissions and a single PRACH transmission, respectively.

[0052] In some arrangements, the base station may configure a configured PRACH target received power specific to each PRACH repetition factor of a plurality of PRACH transmissions, and send a parameter to the UE indicating the configured PRACH target received power configured for each PRACH repetition factor of a plurality of PRACH transmissions (with at least one repetition or retransmission). For example, the PRACH target repetition power is configured by the base station for each PRACH repetition factor. In an example where there are a total of three different PRACH repetition factors for a plurality of PRACH transmissions in a PRACH transmission group, three values ​​of the PRACH target repetition power are configured by the base station for different PRACH repetition factors, and the three values ​​are transmitted to the UE.

[0053] In some arrangements, Figure 4 In the method shown in , determining a transmission power for a plurality of PRACH transmissions includes receiving, by UE 104, an indication of a target receive power configured for the plurality of PRACH transmissions from base station 102. Transmitting the plurality of PRACH transmissions using the transmission power includes transmitting the plurality of PRACH transmissions according to a transmission power determined based on the target receive power configured for the plurality of PRACH transmissions.

[0054] In some examples, Figure 4 In the method shown in , the target received power for multiple PRACH transmissions includes configuring the same configured target received power for multiple repetition factors, each of the multiple repetition factors indicating a different number of transmissions for multiple PRACH transmissions in a PRACH transmission group. In some examples, the target received power for multiple PRACH transmissions includes a configured target received power for each of the multiple repetition factors configured for the multiple PRACH transmissions.

[0055] In some arrangements, a set of DELTA_PREAMBLE values ​​(e.g., a set of delta values) is defined for determining the transmit power for multiple PRACH transmissions in a PRACH transmission group. The set of values ​​is independent of and different from the values ​​for a single PRACH transmission (e.g., a PRACH transmission without duplication). In other words, there are two sets of DELTA_PREAMBLE values ​​for multiple PRACH transmissions and for a single PRACH transmission, respectively. Figure 5 ] is a table showing an example mapping relationship between preamble formats of multiple PRACH transmissions (including retransmissions / repetitions) and a single PRACH transmission and different DELTA_PREAMBLE sets for a PRACH transmission group.

[0056] In some arrangements, Figure 4 In the method shown in , a set of delta values ​​(e.g., DELTA_PREAMBLE) for multiple PRACH transmissions is used to determine a transmission power for multiple PRACH transmissions, the set of delta values ​​corresponding to the preamble format. Transmitting multiple PRACH transmissions using the transmission power includes transmitting multiple PRACH transmissions according to a transmission power determined based on the set of delta values.

[0057] In some arrangements, the set of DELTA_PREAMBLE values ​​for multiple PRACH transmissions may be determined based on the set of DELTA_PREAMBLE values ​​for a single PRACH transmission for a PRACH transmission group. Figure 4 In the method shown in , a set of delta values ​​for multiple PRACH transmissions and an offset are used to determine a set of delta values ​​for multiple PRACH transmissions in a PRACH transmission group. For example, the offset (e.g., X dB) is configured by the base station and sent to the UE, or the offset is predefined. For each corresponding preamble format, the DELTA_PREAMBLE value for multiple PRACH transmissions can be determined by adding X to the DELTA_PREAMBLE value for a single PRACH transmission. In the example where X=6dB, for preamble format 0, the DELTA_PREAMBLE value for multiple PRACH transmissions of preamble format 0 can be determined as X+0=6dB, where the DELTA_PREAMBLE value for a single PRACH transmission of preamble format 0 is 0, as shown in Figure 5 shown.

[0058] In some arrangements, the base station may configure a set of DELTA_PREAMBLE values ​​specific to each PRACH repetition factor of the plurality of PRACH transmissions and send a parameter to the UE indicating the set of DELTA_PREAMBLE values ​​configured for each PRACH repetition factor of the plurality of PRACH transmissions in the PRACH transmission group (having at least one repetition or retransmission). In an example where the plurality of PRACH transmissions in the PRACH transmission group have a total of three different PRACH repetition factors, three sets of DELTA_PREAMBLE values ​​are configured by the base station for the different PRACH repetition factors, and the three sets of DELTA_PREAMBLE values ​​are transmitted to the UE. In some examples, Figure 4 In the method shown in , the set of incremental values ​​for multiple PRACH transmissions includes a set of identical incremental values ​​configured for multiple repetition factors (each of the multiple repetition factors indicates a different number of transmissions for multiple PRACH transmissions in a PRACH transmission group), or a set of incremental values ​​configured for each of the multiple repetition factors for the multiple PRACH transmissions.

[0059] In some arrangements, an additional power offset (e.g., POWER_OFFSET_MULTIPLEPRACH) may be introduced into the calculation formula for PREAMBLE_RECEIVED_TARGET_POWER for multiple PRACH transmissions. For PRACH transmissions with at least one repetition or retransmission, the power offset parameter may be used to adjust the calculation result. For example, the PREAMBLE_RECEIVED_TARGET_POWER used in (1) may be determined by the following formula:

[0060] reambleReceivedTargetPower+DELTA_PREAMBLE

[0061] +(PREAMBLE_POWER_RAMPING_COUNTER-1)

[0062] ×PREAMBLE_POWER_RAMPING_STEP+POWER_OFFSET_2STEP_RA

[0063] +POWER_OFFSET_MULTIPLEPRACH.

[0064] (3)

[0065] Wherein, POWER_OFFSET_MULTIPLEPRACH may be configured by the base station to the UE via RRC signaling, or may be predefined for multiple PRACH transmissions of a RACH transmission group. For a single PRACH transmission of a PRACH transmission group, the value of POWER_OFFSET_MULTIPLEPRACH is 0.

[0066] In some arrangements, Figure 4 In the method shown in , a transmission power is determined for the multiple PRACH transmissions using a power offset for the multiple PRACH transmissions. Transmitting the multiple PRACH transmissions using the transmission power includes transmitting the multiple PRACH transmissions according to the transmission power determined based on the power offset.

[0067] In some arrangements, the base station may configure a POWER_OFFSET_MULTIPLE PRACH value specific to each PRACH repetition factor of multiple PRACH transmissions and send a parameter to the UE indicating the POWER_OFFSET_MULTIPLE PRACH value configured for each PRACH repetition factor of multiple PRACH transmissions (with at least one repetition or retransmission) in the PRACH transmission group. In an example where the multiple PRACH transmissions in the PRACH transmission group have a total of three different PRACH repetition factors, three sets of POWER_OFFSET_MULTIPLE PRACH values ​​are configured by the base station for the different PRACH repetition factors, and the three sets of POWER_OFFSET_MULTIPLE PRACH values ​​are transmitted to the UE. In some arrangements, Figure 4 In the method shown in , the power offset for multiple PRACH transmissions includes the same power offset configured for multiple repetition factors (each of the multiple repetition factors indicates a different number of transmissions for multiple PRACH transmissions in a PRACH transmission group), or includes configuring a power offset for each of the multiple repetition factors for the multiple PRACH transmissions.

[0068] In some arrangements, for a single PRACH transmission, a power ramp-up counter (e.g., PREAMBLE_POWER_RAMPING_COUNTER) is used to record the number of PRACH transmissions or PRACH transmission groups. For multiple PRACH transmissions, a PRACH transmission group includes two or more PRACH transmissions. For multiple PRACH transmissions within a PRACH transmission group, the transmission power may be the same for each of the PRACH transmissions. The power ramp-up counter (e.g., PREAMBLE_POWER_RAMPING_COUNTER) may also be used to record the number of PRACH transmission groups. PREAMBLE_RECEIVED_TARGET_POWER (e.g., the determined preamble received target power) may be determined based on the PRACH repetition factor. For example, PREAMBLE_RECEIVED_TARGET_POWER may be determined using one of the following formulas:

[0069] preambleReceivedTargetPower+DELTA_PREAMBLE

[0070] +(PREAMBLE_POWER_RAMPING_COUNTER×Factor-1)

[0071] ×PREAMBLE_POWER_RAMPING_STEP+POWER_OFFSET_2STEP_RA (4);

[0073] preambleReceivedTargetPower+DELTA_PREAMBLE

[0074] +(PREAMBLE_POWER_RAMPING_COUNTER×Factor-1)

[0075] ×PREAMBLE_POWER_RAMPING_STEP (5);

[0077] preambleReceivedTargetPoWer+DELTA_PREAMBLE

[0078] +(PREAMBLE_POWER_RAMPING_COUNTER×Factor)

[0079] ×PREAMBLE_POWER_RAMPING_STEP

[0080] +POWER_OFFSET_2STEP_RA (6);

[0082] preambleReceivedTargetPower+DELTA_PREAMBLE

[0083] +(PREAMBLE_POWER_RAMPING_COUNTER×Factor)

[0084] ×PREAMBLE_POWER_RAMPING_STEP (7);

[0086] preambleReceivedTargetPower+DELTA_PREAMBLE

[0087] +(PREAMBLE_POWER_RAMPING_COUNTER-1)

[0088] ×PREAMBLE_POWER_RAMPING_STEP×Factor

[0089] +POWER_OFFSET_2STEP_RA (8);

[0091] preambleReceivedTargetPower+DELTA_PREAMBLE

[0092] +(PREAMBLE_POWER_RAMPING_COUNTER-1)

[0093] ×PREAMBLE_POWER_RAMPING_STEP×Factor

[0094] (9)

[0095] Where Factor represents the PRACH repetition factor or the number of PRACH transmissions in a PRACH transmission group. Figure 4 In the method shown in , a repetition factor for a plurality of PRACH transmissions is used to determine the transmission power for the plurality of PRACH transmissions. The repetition factor indicates the number of transmissions of the plurality of PRACH transmissions in a PRACH transmission group.

[0096] In some arrangements, the transmission power for each PRACH repetition transmission in a PRACH transmission group may be determined. For a single PRACH transmission, a power ramp-up counter (e.g., PREAMBLE_POWER_RAMPING_COUNTER) is used, and a power ramp-up step size (e.g., PREAMBLE_POWER_RAMPING_STEP) is configured. For multiple PRACH transmissions in a PRACH transmission group, an independent power ramp-up counter may be introduced. In other words, two independent or different power ramp-up counters may be used for multiple PRACH transmissions. As an example, a first power ramp-up counter C1 represents a power ramp-up counter for counting and recording the current number of PRACH repetitions within the same PRACH transmission group, while a second power ramp-up counter C2 represents a power ramp-up counter for counting and recording the current number of PRACH transmission groups. In some arrangements, in Figure 4 In the method shown in, a first power climbing counter (e.g., C1) and a second power climbing counter (e.g., C2) are used to determine the transmission power for multiple PRACH transmissions, the first power climbing counter counts the current number of multiple PRACH transmissions, and the second power climbing counter counts the current number of PRACH transmission groups.

[0097] In some arrangements, independent or different power ramping steps may be defined between PRACH repetitions within the same PRACH transmission group or across different PRACH transmission groups. In other words, a base station may define or configure two independent or different power ramping steps for multiple PRACH transmissions. In some examples, the power ramping step between different transmissions within the same PRACH transmission group may be P1, and the power ramping step between PRACH transmissions within different PRACH transmission groups may be P2.

[0098] In some arrangements, PREAMBLE_RECEIVED_TARGET_POWER may be determined based on the power ramp step sizes P1 and P2 and the power ramp counters C1 and C2. For example, PREAMBLE_RECEIVED_TARGET_POWER may be determined by: preambleReceivedTargetPower+DELTA_PREAMBLE+(C1-1)×P1+

[0099] (C2-1)×P2 (10)

[0100] Figure 6: is a table showing an example PREAMBLE_RECEIVED_TARGET_POWER determined using expression (10) based on a counter C1 for counting or recording the number of PRACH repetitions and a counter C2 for counting or recording the number of PRACH transmission groups. Figure 7 : is a table showing an example PREAMBLE_RECEIVED_TARGET_POWER determined using expression (10) based on a counter C1 for counting or recording the number of PRACH repetitions and a counter C2 for counting or recording the number of PRACH transmission groups. Figure 6 and Figure 7 The PREAMBLE_RECEIVED_TARGET_POWER determined based on the number of repetitions across different PRACH transmission groups is shown.

[0101] In some arrangements, Figure 4 In the method shown in , a transmission power is determined for multiple PRACH transmissions using a first power climbing step size and a second power climbing step size. The first power climbing step size is the difference between two adjacent PRACH transmissions within a PRACH transmission group. There is no other PRACH transmission between two adjacent PRACH transmissions. The second power climbing step size is the difference between a first PRACH transmission in a PRACH transmission group and a second PRACH transmission in another PRACH transmission group. In some examples, the first PRACH transmission in a PRACH group is the last PRACH transmission in the first PRACH group (in time), and the second PRACH transmission in another PRACH group is the first PRACH transmission in the second PRACH group (in time). In some examples, the first PRACH group and the second PRACH group are two adjacent PRACH groups, and the first PRACH group is before the second PRACH group in time.

[0102] In some arrangements, a transmission power may be determined for each PRACH repetition transmission in a PRACH transmission group. Figure 8 is a diagram illustrating SSB-RSRP thresholds 802, 804, 806, and 808 (eg, power thresholds) corresponding to PRACH repetition factors according to some arrangements. At least one SSB-RSRP threshold (eg, threshold 802) may be used by a UE to determine whether to enter a PRACH repetition mode.

[0103] In some arrangements, in response to the UE determining that the SSB-RSRP measurement result of the UE is greater than or equal to 802, the UE uses a single PRACH transmission. In response to the UE determining that the PRACH transmission power reaches a maximum value or the retransmission of the PRACH reaches a predefined number (e.g., configured or predefined by the base station via RRC signaling), and the RACH process has failed, the UE initiates the PRACH process in a repetition mode, in which, in response to the failure, the UE transmits the PRACH with at least one repetition in a subsequent RACH process.

[0104] In some arrangements, if the UE selects a single PRACH transmission on the first attempt, but the initial access fails after multiple PRACH retries, it is preferable for the UE to directly use multiple PRACH transmissions when initiating a new PRACH transmission. preambleTransMax (e.g., X) can be reused as a threshold for the UE to initiate multiple PRACH transmissions. If the number of PRACH attempts exceeds preambleTransMax and the initial access failure is declared, the UE will attempt multiple PRACH transmissions thereafter. Or a new parameter less than preambleTransMax can be configured as the threshold for the UE to initiate a single PRACH attempt for multiple PRACH transmissions before declaring an initial access failure. Or a new parameter (e.g., a coefficient θ) is configured, and θ×X is defined as the threshold for the UE to initiate a single PRACH attempt for multiple PRACH transmissions. Where 0<θ≤1.

[0105] In some arrangements, in response to the UE determining that the UE's SSB-RSRP measurement result is below threshold 802, the UE initiates a repetition mode (e.g., transmitting PRACH with at least one repetition), and the PRACH repetition factor may be determined by the UE. In some arrangements, multiple thresholds (e.g., thresholds 804, 806, and 808) may be predefined, or configured / sent to the UE by the base station to assist the UE in determining different repetition factors. For example, in response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 802 and 804, the UE implements a PRACH repetition factor of 2 (e.g., 2 transmissions) within the PRACH transmission group. In response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 804 and 806, the UE implements a PRACH repetition factor of 4 (e.g., 4 transmissions) within the PRACH transmission group. In response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 806 and 808, the UE implements a PRACH repetition factor of 8 (e.g., 8 transmissions) within the PRACH transmission group. In response to determining that the initial power of the UE has not reached a maximum value, the UE increases power between different repetitions within the same PRACH transmission group to increase access probability and reduce access delay.

[0106] In some arrangements, in response to the UE determining that the UE's SSB-RSRP measurement result is below threshold 802, the UE initiates a repetition mode (e.g., transmitting PRACH with at least one repetition) and transmits the multiple PRACH transmissions using a maximum transmission power. In some arrangements, the UE may determine a repetition factor. In some arrangements, multiple thresholds (e.g., thresholds 804, 806, and 808) may be predefined or configured / sent to the UE by the base station to assist the UE in determining different repetition factors. For example, in response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 802 and 804, the UE implements a PRACH repetition factor of 2 (e.g., 2 transmissions) within the PRACH transmission group. In response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 804 and 806, the UE implements a PRACH repetition factor of 4 (e.g., 4 transmissions) within the PRACH transmission group. In response to the UE determining that the UE's SSB-RSRP measurement result is between thresholds 806 and 808, the UE implements a PRACH repetition factor of 8 (e.g., 8 transmissions) within the PRACH transmission group. Figure 4 In the method shown in , determining the transmission power includes determining that the measurement result is less than a threshold (e.g., threshold 802). In response to determining that the measurement result is less than the threshold, the UE determines to use the maximum transmission power to send multiple PRACH transmissions in the PRACH transmission group.

[0107] In some arrangements, a relationship may be defined between the transmission power for multiple PRACH transmissions within the same PRACH transmission group (eg, with repeated PRACH transmissions) and the transmission power for Msg.3 transmissions (eg, Physical Uplink Shared Channel (PUSCH)).

[0108] In some arrangements, for multiple PRACH transmissions in a PRACH transmission group, the UE may determine the msg3 transmission power based on the transmission power of the last PRACH transmission or the previous PRACH transmission in the multiple PRACH transmissions. For example, the UE may transmit msg3 using the power of the last PRACH repetition in the last PRACH transmission group. In some arrangements, a PRACH preamble transmission (e.g., msg1) is transmitted by the UE to the base station. The UE may receive a response (e.g., msg2) from the base station. The UE transmits a PUSCH as msg3 in the UL grant provided in Msg2. In some arrangements, in Figure 4 The method shown in , includes determining the transmission power for uplink transmission (eg, msg3, PUSCH, etc.) based on the transmission power of the last PRACH transmission of multiple PRACH transmissions in a PRACH transmission group.

[0109] In some arrangements, the UE may determine the transmission power for msg3 based on the transmission power of the PRACH transmission indicated by the base station. For example, within the last PRACH transmission group or the previous PRACH transmission group, four PRACH transmissions are transmitted by the UE at transmission powers P1, P2, P3, and P4, respectively. The BS may indicate one of the transmission powers P1, P2, P3, and P4 to the UE to determine the transmission power for msg3. The BS may send a 2-bit indication included in msg2 / RAR, and each value of the 2 bits corresponds to a corresponding transmission power. For example, 00 corresponds to P1, 01 corresponds to P2, 10 corresponds to P3, and 11 corresponds to P4. In some arrangements, Figure 4 The method shown in includes determining a transmission power for an uplink transmission (eg, msg3, PUSCH, etc.) based on an indication received from a base station, the indication indicating one of a plurality of transmission powers used to transmit a plurality of PRACH transmissions in a PRACH transmission group.

[0110] In some examples, the UE may receive an RRC parameter (e.g., msg3-DeltaPreamble) from the base station indicating a power offset between a PRACH transmission and a msg3 transmission. In some examples, the value of the RRC parameter may be configured for different combinations of a repetition factor for PRACH repetition and a repetition factor for msg3 repetition. For example, Fig. 9 is a table showing an example relationship between msg3-DeltaPreamble, repetition factor of PRACH and repetition factor of Msg3 according to some arrangements. Then, for different repetition factor combinations for PRACH and msg3 transmission, the corresponding Δ is used as msg3-DeltaPreamble to determine the transmission power for msg3. In some arrangements, Figure 4 The method shown in includes receiving an offset between a transmission power of one of a plurality of PRACH transmissions and a transmission power of an uplink transmission from a base station, the offset being mapped to a repetition factor of the plurality of PRACH transmissions and a repetition factor for uplink transmission. The transmission power is determined by a UE based on the transmission power of one of the plurality of PRACH transmissions and the offset.

[0111] In some arrangements, the scaling factor is defined according to at least one of the PRACH repetition factor and the msg3 repetition factor. For example, the scaling factor Y is defined as the ratio of the PRACH repetition factor M to the msg3 repetition factor N (e.g., Y=M / N). The transmission power of msg3 can be determined by the UE according to the scaling factor and the msg3-DeltaPreamble. For example, the transmission power of msg3 can be determined using the following formula: Transmission Power ofmsg3=Power ofPRACH+Scaling Factor×

[0112] Value ofmsg3-DeltaPreamble(11)

[0113] In some arrangements, the UE may determine the scaling factor Y based on a reference value Q and a ratio of the PRACH repetition factor M to the msg3 repetition factor N, for example, Y=Q×(M / N). The transmission power of msg3 may be determined by the UE based on the scaling factor and the msg3-DeltaPreamble. For example, the transmission power of msg3 may be determined using the following formula:

[0114] Transmission Power of msg3=power of PRACH+scaling factor+value ofmsg3-DeltaPreamble (12)

[0115] In some arrangements, Figure 4 The method shown in includes determining a scaling factor based on a repetition factor of multiple PRACH transmissions and a repetition factor of an uplink transmission, and determining a transmission power of an uplink transmission based on a transmission power of one of the multiple PRACH transmissions and the scaling factor. In some examples, the scaling factor is a ratio of the repetition factor of the multiple PRACH transmissions to the repetition factor of the uplink transmission. In some examples, the scaling factor is determined based on the repetition factor of the multiple PRACH transmissions, the repetition factor of the uplink transmission, and a reference value. In some examples, the transmission power for the uplink transmission is based on the transmission power of one of the multiple PRACH transmissions, the scaling factor, and the value of msg3-DeltaPreamble.

[0116] UE transmit power is the most valuable resource in the uplink, and enhancements that unlock additional uplink power are very valuable for uplink coverage. One of the possible ways to improve uplink coverage in the power domain includes enhancements to reduce the maximum power reduction (MPR) and peak-to-average ratio (PAR) of the transmitted signal. Frequency domain spectrum shaping (FDSS) with and without spectrum spreading is a promising solution to reduce MPR and PAR. In an example where FDSS with spectrum spreading is employed, as described herein, a spreading factor may be indicated.

[0117] Fig.10 is a block diagram of a discrete Fourier transform spread spectrum orthogonal frequency division multiplexing (DFT-S-OFDM) transmitter with FDSS and spectrum spreading according to some arrangements. The differences compared to conventional DFT-S-OFDM are shown in grey.

[0118] In some arrangements, the first step to be taken is to define the symbols to be used to model the spectrum extension. M is represented as the number of modulation constellation symbols in RBs, which is also the size of the DFT operation, N is represented as the total number of OFDM subcarriers in RBs, and E is represented as the number of subcarriers used for spectrum extension in RBs. Therefore, the extension factor (denoted as β) can be defined in the following two ways, Definition 1 and Definition 2.

[0119] Definition 1: The extension factor (β) is the given spectrum extension size / total allocation size, that is, β=E / N.

[0120] Definition 2: The expansion factor (β) is the given spectrum expansion size / modulation constellation symbol size, that is, β=E / M.

[0121] Currently, frequency domain resource allocation is indicated by scheduling grant or high-level configuration. When FDSS with spectrum extension is introduced, UE interprets frequency domain resource allocation including interpretation 1 and interpretation 2.

[0122] Interpretation 1: The UE interprets the frequency domain resource allocation as the total number of OFDM subcarriers (N), which includes the spectrum extension part.

[0123] Interpretation 2: The UE interprets the frequency domain resource allocation as the number of modulation constellation symbols (M), which excludes the spectrum extension part.

[0124] The definition of the spreading factor should be consistent with the interpretation of the frequency domain resource allocation. If the UE interprets the frequency domain resource allocation as the total number of OFDM subcarriers (N), then definition 1 should be used, otherwise, definition 2 should be used instead. In the following, examples are given to illustrate the difference between the two cases. Assume that the frequency domain resource allocation indicates that the UE is allocated 32 consecutive RBs and the spreading factor β is 0.25. There are 12 subcarriers in one RB. Then the two cases will be shown in Fig.11 and Fig.12 middle.

[0125] Fig.11 is a diagram showing examples of resources according to various arrangements. Fig.11 In the implementation of Explanation 1 and Definition 1. The total number of OFDM subcarriers N is 32, then the number of subcarriers used for spectrum extension is E = β * N = 0.25 * 32 = 8, and the number of constellation symbols and the DFT size can be M = (1-β) * N = (1-0.25) * 32 = 24.

[0126] Fig.12 is a diagram showing examples of resources according to various arrangements. Fig.12 In the implementation of Explanation 2 and Definition 2. The number of constellation symbols (and DFT size) M is 32, then the number of subcarriers used for spectrum extension is E = β * M = 0.25 * 32 = 8. The total number of OFDM subcarriers N can be N = (1 + β) * M = (1 + 0.25) * 32 = 40.

[0127] In some arrangements, there is a restriction that the spectrum extension size E should be expressed in integer units of RB. This will restrict the possible values ​​of the extension factor α. In the case where Interpretation 1 and Definition 1 are used for FDSS with spectrum extension, there is also a restriction that the value of M should also be expressed in integer units that can be 2 α2 *3 α3 *5 α5 In the current NR specification, FDSS with spectrum extension is not adopted, so the frequency domain resource allocation of DFT-S-OFDM should follow the principle of resource allocation. That is, the value N in RB units is also 2 α2 *3 α3 *5 α5 multiples of. Fig.13 is a table listing possible values ​​of the spreading factor that can be configured for different values ​​of N (in units of RB) according to various arrangements. Fig.13 Spreading factors greater than 0.5 are not considered in the table shown, because larger spreading factors result in higher data transmission code rates, which can degrade link-level performance.

[0128] In some examples, Fig.13 Alternatively, you can use another format such as Fig.14 shown. Fig.14 is a table listing possible values ​​of spreading factor that may be configured for different values ​​of N (in units of RBs) according to various arrangements.

[0129] For Interpretation 2 and Definition 2, the frequency domain resource allocation is equal to the value of M, and the value of M does not depend on the extension factor. Therefore, the extension factor should be set to meet the requirement that "the spectrum extension size E should be expressed in integer units of RB". If symmetric extension is adopted, the above requirement should be modified to "the spectrum extension size E should be expressed in even integer units of RB". The extension factors shown in Table-1 assume that symmetric extension is used.

[0130] Under the restriction of "the spectrum extension size E should be expressed in integer units of RB" or "the spectrum extension size E should be expressed in even integer units of RB", when determining the spectrum extension side, E can be calculated by at least one of the following formulas.

[0131] In some arrangements, for Definition 1:

[0132] (1) E = ceil (β * N)

[0133] (2) E = ceil (β*N / 2)*2.

[0134] (3)If floor(β*N)>0,then E=round(β*N)

[0135] (4)If floor(β*N / 2)>0,then E=round(β*N / 2)*2

[0136] For Definition 2, M is used instead of N in the above formula.

[0137] In some examples, "ceil" refers to a round-up operation and "floor" refers to a round-down operation.

[0138] In some arrangements, there are several options to indicate the expansion factor. The options include, but are not limited to:

[0139] Option 1: Predefined value for a given N_RB.

[0140] Option 2: RRC is configured

[0141] Option 3: RRC is configured and DCI is indicated. Regarding DCI indication, the following should be considered.

[0142] Option 3-1: New DCI field

[0143] Solution 3-2: Reuse the existing DCI field.

[0144] In solution 1, when the UE gets the frequency domain resource allocation, whether the UE interprets it as M or N, the spreading factor can be obtained accordingly. The relationship between the number of allocated RBs (N_RB) and the spreading factor is predefined and both the UE and the gNB have a common understanding. The spreading factor for a given N_RB can be set based on a lot of simulations to find the best value of the spreading factor that achieves the best performance. This option is the simplest, but the least flexible.

[0145] In solution 2, the expansion factor can be configured through RRC signaling. In one embodiment, the expansion factor can be configured in pusch-Config or ConfiguredGrantConfig. And the reconfiguration of the expansion factor can be achieved through RRC reconfiguration. In this way, considerable flexibility can be achieved.

[0146] In option 3, multiple spreading factors are configured via RRC. Similar to option 2, multiple spreading factors can be configured in pusch-Config or ConfiguredGrantConfig. And for a given PUSCH transmission, the spreading factor used is indicated by the scheduling DCI or activation DCI for the corresponding PUSCH transmission.

[0147] Regarding DCI indication, in some arrangements, a new DCI field is introduced in the DCI to indicate the extension factor. The size of the new control field depends on the number of extension factors configured in the RRC. In some arrangements, 2 bits are introduced for the extension factor indication, so a maximum of 4 extension factors can be configured in the RRC.

[0148] In some arrangements, the extension factor may be indicated by reusing an existing DCI field. For example, the extension factor may be indicated by an MCS index control field. Fig.15is a table showing an MCS index table for PUSCH with transform precoding (also known as DFT-s-OFDM PUSCH) according to various arrangements. Considering the scenario with limited uplink coverage, a low MCS index will be used. In this case, if the MCS index for FDSS with spectrum spreading is limited to 0 to 7, only 3 LSBs are sufficient for MCS indication, then the two MSBs in the MCS control field can be reused to indicate the extension factor. Then, one of the 4 RRC-configured extension factors can be indicated by the 2 MSBs in the MCS control field. In this case, the UE should know whether it should reinterpret the MCS control field. In some arrangements, if FDSS with spectrum spreading is configured for the UE, it should reinterpret the MCS field. Only 3 LSBs are used to indicate the MCS index, while 2 MSBs are used to indicate the extension factor.

[0149] In some arrangements, the expansion factor can be implicitly derived from the MCS index. Based on some preliminary evaluation results, for lower MCS indices (corresponding to lower code rates), larger expansion factors can be used. In this case, it is assumed that the number of expansion factors configured in RRC is K, and the expansion factors are configured in descending order, i.e., β0>β1>β2>...>β k-1 The K MCS index thresholds are predefined. For a given MCS index I MCS , can be based on Fig.16 Get the expansion factor β.

[0150] As an example, consider that FDSS with spectrum spreading is only applicable to pi / 2-BPSK and QPSK, then the MCS index will be 0 to 9. In some arrangements, assuming that 4 spreading factors are configured in RRC, then the MCS index can be based on Fig.17 Get the expansion factor β.

[0151] In some arrangements, the spreading factor may be obtained by specifying, for at least one MCS index I MCS The RRC configuration is derived from the MCS index. For MCS index I without a configured expansion factor MCS , FDSS with spectrum spreading is not applied. Considering that FDSS with spectrum spreading is only applicable to pi / 2-BPSK and QPSK, the MCS index will be 0 to 9. Assuming that 4 spreading factors are configured in RRC, the spreading factor β can be calculated based on Fig.18 Get. For I MCS = 2, apply β0, and for I MCS =6, FDSS with spectrum extension is not applied.

[0152] In some arrangements, the extension factor may be derived by an existing field with enhancement (e.g., configuring another column of the TDRA table to indicate the extension factor) or a new field. And whether FDSS with spectrum extension is applied depends on two fields, namely, MCS The MCS field and the above fields indicated by the extension factor for the valid extension factor. MCS It is the MCS index 0 to 7. For example, MCS index I MCS = 2 and the row indicated in the TDRA table also configures the extension factor, then FDSS with spectrum extension is applied. For another example, MCS index I MCS = 2 and a row indicated in the TDRA table does not configure the extension factor, then FDSS with spectrum extension is not applied. For another example, MCS index I MCS = 10 and the row indicated in the TDRA table configures the spreading factor, then FDSS with spectrum spreading is not applied. For another example, MCS index I MCS =10 and a row indicated in the TDRA table does not configure the extension factor, then FDSS with spectrum extension is not applied.

[0153] In some arrangements, the expansion factor may be derived via SIBx and / or RAR grant for msg3 / 5 (re)transmission. For example, the expansion factor may be derived via SIBx indication and optionally applied only to msg3 / 5 and / or applied until a UE-specific RRC configuration is received. For another example, the expansion factor may be derived via RAR grant indication and optionally candidate expansion factors may be predefined or indicated via SIBx, optionally one or more fields in the RAR grant (e.g., X MSB bits of the MCS field) may be represented to indicate the expansion factor. If the number of repetitions of msg3 also needs to be indicated, the codepoint table (e.g., Fig.19 ), the first column is the number of repetitions and the second column is the expansion factor.

[0154] In some arrangements, the extension factor may be derived through an existing field with enhancements (e.g., using the X MSB bits of the MCS field to indicate the extension factor), or through a new field in DCI format 0_0. If the number of bits of DCI format 1_0 before padding is greater than the number of bits of DCI format 0_0 before padding, the new field for the extension factor indication is located before the padding, or after the padding bits, and in the second to last or third bit before the UL / SUL indicator and / or waveform indicator.

[0155] In some arrangements, in case of scheduling retransmission of msg3 or transmission / retransmission of msg5 by DCI format 0_0, the expansion factor may be derived by the indication of format 0_0. Optionally, the indicated expansion factor should be the same as the expansion factor of the previous transmission of the same TB or msg3 initial transmission. Or the expansion factor may be implicitly derived by the previous transmission of the same TB or msg3 initial transmission and the indication of format 0_0 is discarded.

[0156] Although various arrangements of the present disclosure have been described above, it should be understood that they are presented only as examples rather than as limitations. Similarly, various figures may depict exemplary architectures or configurations, and these examples are provided so that those of ordinary skill in the art can understand the example features and functions of the present solution. However, these people should understand that the solution is not limited to the example architectures or configurations shown, but can be implemented using various alternative architectures and configurations. In addition, as those of ordinary skill in the art should understand, one or more features of an arrangement may be combined with one or more features of another arrangement described herein. Therefore, the breadth and scope of the present disclosure should not be limited to any of the above-mentioned illustrative embodiments.

[0157] It should also be understood that any reference to an element using names such as "first," "second," etc., herein generally does not limit the number or order of these elements. Rather, these names may be used herein as a convenient means of distinguishing between two or more elements or instances of an element. Thus, reference to a first and a second element does not mean that only two elements can be used, or that the first element must precede the second element in some manner.

[0158] In addition, it should be understood by those skilled in the art that any of a variety of different technologies and techniques may be used to represent information and signals. For example, data, instructions, commands, information, signals, bits, and symbols that may be 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.

[0159] It should also be understood by those of ordinary skill in the art 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 both), firmware, various forms of programs or design codes containing instructions (for convenience, they may be referred to herein as "software" or "software modules"), or any combination of these technologies. In order to clearly illustrate this interchangeability of hardware, firmware, and software, various illustrative components, blocks, modules, circuits, and steps have been generally described above according to their functions. Such functions are implemented as hardware, firmware, or as software, or as a combination of these technologies, depending on the specific application and the design constraints imposed on the entire system. Those of ordinary skill in the art may implement the described functions in various ways for each specific application, but such implementation decisions will not result in deviations from the scope of the present disclosure.

[0160] In addition, it will be appreciated by those of ordinary skill in the art that the various illustrative logic blocks, modules, devices, components, and circuits described herein may be implemented within or performed by 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. A 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, for example, a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors combined with a DSP core, or any other suitable configuration that performs the functions described herein.

[0161] If implemented in software, the functionality may be stored as one or more instructions or codes on a computer-readable medium. Therefore, the steps of the method or algorithm disclosed herein may be implemented as software stored on a computer-readable medium. Computer-readable media include computer storage media and communication media, and communication media include any media that can transfer a computer program or code from one place to another. The storage medium can be any available medium that a computer can access. As an example but not limited to this, such computer-readable media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired program code in the form of instructions or data structures and can be accessed by a computer.

[0162] In this application, the term "module" as used herein refers to software, firmware, hardware, and any combination of these elements for performing the relevant functions described herein. In addition, for the purpose of discussion, various modules are described as separate modules; however, as is apparent to one of ordinary skill in the art, two or more modules can be combined to form a single module that performs the associated functions of the arrangements according to the present disclosure.

[0163] In addition, in the arrangement of the present solution, memory or other memory and communication components can be used. It should be understood that, for the sake of clarity, the above description has described the arrangement of the present solution with reference to different functional units and processors. However, it is obvious that any appropriate functional distribution between different functional units, processing logic elements or domains can be used without departing from the present solution. For example, the function illustrated as being performed by a separate processing logic element or controller can be performed by the same processing logic element or controller. Therefore, reference to a specific functional unit is only a reference to an appropriate manner for providing the described function, rather than indicating a strict logical or physical structure or organization.

[0164] Various modifications to the embodiments described in this 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 this disclosure. Therefore, this disclosure is not intended to be limited to the embodiments shown herein, but is to be consistent with the broadest scope consistent with the novel features and principles disclosed herein, as described in the following claims.

Claims

1. A wireless communication method, comprising: determining, by a wireless communication device, a transmission power for a plurality of physical random access channel (PRACH) transmissions in a PRACH transmission group; as well as The plurality of PRACH transmissions are transmitted by the wireless communication device to a base station using the transmission power.

2. The method according to claim 1, wherein The multiple PRACH transmissions include an initial PRACH transmission and at least one repetition or at least one retransmission of the initial PRACH transmission in the same PRACH transmission group.

3. The method according to claim 1, wherein Determining transmit powers for the plurality of PRACH transmissions Determining transmit powers for the plurality of PRACH transmissions comprises receiving, by the wireless communication device from the base station, an indication of a target receive power configured for the plurality of PRACH transmissions; and Transmitting the plurality of PRACH transmissions using the transmission power includes transmitting the plurality of PRACH transmissions according to a transmission power determined based on a target received power configured for the plurality of PRACH transmissions.

4. The method according to claim 3, wherein: The target received powers configured for the multiple PRACH transmissions include: configuring the same configured target received power for multiple repetition factors, each of the multiple repetition factors indicating a different number of transmissions for multiple PRACH transmissions in the PRACH transmission group; or A configured target received power is configured for each of a plurality of repetition factors configured for a plurality of PRACH transmissions.

5. The method according to claim 1, wherein determining a transmit power for the plurality of PRACH transmissions using a set of delta values ​​for the plurality of PRACH transmissions, the set of delta values ​​corresponding to a preamble format; and Transmitting the plurality of PRACH transmissions using the transmission power includes transmitting the plurality of PRACH transmissions according to a transmission power determined based on the set of delta values.

6. The method according to claim 5, comprising: The set of delta values ​​for the plurality of PRACH transmissions is determined using the set of delta values ​​for a single PRACH transmission in a PRACH transmission group and an offset.

7. The method according to claim 5, wherein: The set of increment values ​​for the plurality of PRACH transmissions includes: configuring a set of same increment values ​​for a plurality of repetition factors, each of the plurality of repetition factors indicating a different number of transmissions for a plurality of PRACH transmissions in the PRACH transmission group; or A set of incremental values ​​is configured for each of the multiple repetition factors of the multiple PRACH transmissions.

8. The method according to claim 1, wherein: determining a transmit power for the plurality of PRACH transmissions using a power offset for the plurality of PRACH transmissions; determining a transmit power for the plurality of PRACH transmissions; as well as Transmitting the plurality of PRACH transmissions using the transmit power comprises transmitting the plurality of PRACH transmissions according to the transmit power determined based on the power offset.

9. The method according to claim 8, wherein: The power offsets used for the plurality of PRACH transmissions include: configuring a same power offset for a plurality of repetition factors, each of the plurality of repetition factors indicating a different number of transmissions for a plurality of PRACH transmissions in the PRACH transmission group; or A power offset is configured for each of a plurality of repetition factors of the plurality of PRACH transmissions.

10. The method according to claim 1, wherein: The transmission power is determined for the plurality of PRACH transmissions using a repetition factor for the plurality of PRACH transmissions, wherein the repetition factor indicates a number of transmissions of the plurality of PRACH transmissions in the PRACH transmission group.

11. The method according to claim 1, wherein: A first power ramp counter and a second power ramp counter are used to determine transmission power for the multiple PRACH transmissions. The first power ramp counter counts a current number of the multiple PRACH transmissions, and the second power ramp counter counts a current number of PRACH transmission groups.

12. The method according to claim 1, wherein: The transmission power for the multiple PRACH transmissions is determined using a first power climbing step size and a second power climbing step size, wherein the first power climbing step size is a difference between two adjacent PRACH transmissions within the PRACH transmission group, and the second power climbing step size is a difference between a first PRACH transmission in the PRACH transmission group and a second PRACH transmission in another PRACH transmission group.

13. The method according to claim 1, wherein: Determining the transmission power includes: determining that the measurement result is less than a threshold value; and In response to determining that the measurement result is less than the threshold, determining to use a maximum transmission power to transmit a plurality of PRACH transmissions in the PRACH transmission group.

14. The method according to claim 1, comprising: The transmission power is determined for the uplink transmission based on the transmission power used to transmit a last PRACH transmission of a plurality of PRACH transmissions within the PRACH transmission group.

15. The method according to claim 1, comprising: A transmission power is determined for an uplink transmission based on an indication received from a base station, the indication indicating one of a plurality of transmission powers to be used for transmitting a plurality of PRACH transmissions in the PRACH transmission group.

16. The method according to claim 1, comprising: receiving, from the base station, an offset between a transmission power of one of the plurality of PRACH transmissions and a transmission power for an uplink transmission, the offset being mapped to a repetition factor of the plurality of PRACH transmissions and a repetition factor of the uplink transmission; as well as A transmit power is determined for the uplink transmission based on a transmit power of one of the plurality of PRACH transmissions and the offset.

17. The method according to claim 1, comprising: determining a scaling factor based on a repetition factor of the plurality of PRACH transmissions and a repetition factor of an uplink transmission; as well as A transmission power is determined for the uplink transmission based on a transmission power of one of the plurality of PRACH transmissions and the scaling factor.

18. The method according to claim 17, wherein: The scaling factor is a ratio of a repetition factor of the plurality of PRACH transmissions to a repetition factor of the uplink transmission.

19. The method according to claim 17, wherein: The scaling factor is determined based on a repetition factor of the plurality of PRACH transmissions, a repetition factor of the uplink transmission, and a reference value.

20. The method according to claim 17, wherein: The transmission power for the uplink transmission is based on the transmission power of one PRACH transmission among the plurality of PRACH transmissions, the scaling factor and a value of msg3-DeltaPreamble.

21. A wireless communication device, comprising at least one processor and a memory, wherein: The at least one processor is configured to read code from the memory and implement the method according to claim 1.

22. A computer program product comprising computer readable program medium code stored thereon, which, when executed by at least one processor, causes the at least one processor to implement the method according to claim 1.

23. A wireless communication method, comprising: sending, by a base station to a wireless communication device, a parameter used by the wireless communication device to determine transmission power for a plurality of physical random access channel (PRACH) transmissions in a PRACH transmission group; as well as The plurality of PRACH transmissions are received, by the base station, from the wireless communication device based on the transmission power.

24. A wireless communication device, comprising at least one processor and a memory, wherein: The at least one processor is configured to read code from the memory and implement the method according to claim 23.

25. A computer program product comprising computer readable program medium code stored thereon, which, when executed by at least one processor, causes the at least one processor to implement the method according to claim 23.

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