Method and apparatus for transmitting a signal in wireless communication system

Abstract

The present disclosure relates to a 5G (5th generation) or pre-5G communication system for supporting higher data transmission rates than a 4G (4th generation) communication system such as LTE (Long Term Evolution). The present disclosure provides a method of operation of a terminal (user equipment, UE) in a wireless communication system. The method comprises: receiving configuration information for two-step random access transmission from a base station; determining a resource configuration for transmitting a first message of the two-step random access transmission based on the received configuration information for the two-step random access transmission; transmitting the first message to the base station according to the determined resource configuration, wherein the first message includes a preamble and data; detecting a second message from the base station as feedback of the first message; and performing a subsequent operation according to the detected second message.

Description

Technology Field

[0001] The present disclosure generally relates to a wireless communication system, and more specifically to a method and apparatus for transmitting a signal in a wireless communication system. Background Technology

[0003] 4G(4 th To meet the increasing demand for wireless data traffic following the commercialization of the (generation) communication system, improved 5G (5 th Efforts are being made to develop 5G communication systems or pre-5G communication systems. For this reason, 5G communication systems or pre-5G communication systems are referred to as Beyond 4G Network communication systems or Post-LTE systems.

[0004] To achieve high data transmission rates, 5G communication systems are being considered for implementation in the mmWave band (e.g., the 60 GHz band). To mitigate path loss and increase the transmission distance of radio waves in the mmWave band, beamforming, massive MIMO, full Dimensional MIMO (FD-MIMO), array antenna, analog beamforming, and large-scale antenna technologies are being discussed for 5G communication systems.

[0005] In addition, to improve the network of the system, technologies such as advanced small cell, advanced small cell, cloud radio access network (cloud RAN), ultra-dense network, Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation are being developed in 5G communication systems.

[0006] In addition, advanced coding modulation (ACM) methods such as FQAM (Hybrid Frequency Shift Keying and Quadrature Amplitude Modulation) and SWSC (Sliding Window Superposition Coding), as well as advanced access technologies such as FBMC (Filter Bank Multi Carrier), NOMA (Non Orthogonal Multiple Access), and SCMA (Sparse Code Multiple Access) are being developed in 5G systems. The problem to be solved

[0008] Based on the discussion above, the present disclosure provides a method and apparatus for transmitting a signal in a wireless communication system. means of solving the problem

[0010] According to various embodiments of the present disclosure, a method of operation of a terminal (user equipment, UE) in a wireless communication system is provided. The method comprises: receiving configuration information for two-step random access transmission from a base station; determining a resource configuration for transmitting a first message of the two-step random access transmission based on the received configuration information for the two-step random access transmission; transmitting the first message to the base station according to the determined resource configuration, wherein the first message includes a preamble and data; detecting a second message from the base station as feedback of the first message; and performing a subsequent operation according to the detected second message.

[0011] According to various embodiments of the present disclosure, a method of operation of a base station in a wireless communication system is provided. The method comprises the steps of: transmitting configuration information for two-stage random access transmission to a terminal (user equipment, UE); receiving a first message according to a resource configuration determined based on the configuration information; and transmitting a second message to the terminal as feedback of the first message, wherein the first message includes a preamble and data, and the second message includes at least one of a contention resolution identifier, an uplink grant, a cell radio network temporary identifier (C-RNTI), a timing advance value, a physical uplink control channel (PUCCH) resource indication, scheduling information for downlink transmission, a fallback indicator, or a backoff indicator.

[0012] According to various embodiments of the present disclosure, a terminal is provided in a wireless communication system. The terminal comprises: a transceiver; and at least one processor functionally coupled to the transceiver, wherein the at least one processor receives configuration information for two-step random access transmission from a base station, determines a resource configuration for transmitting a first message of the two-step random access transmission based on the received configuration information for the two-step random access transmission, wherein the first message includes a preamble and data, transmits the first message to the base station according to the determined resource configuration, detects a second message from the base station as feedback of the first message, and is configured to perform a subsequent operation according to the detected second message.

[0013] According to various embodiments of the present disclosure, a base station is provided in a wireless communication system. The base station comprises: a transceiver; and at least one processor functionally coupled to the transceiver, wherein the at least one processor transmits configuration information for two-stage random access transmission to a terminal (user equipment, UE) and receives a first message according to a resource configuration determined based on the configuration information, wherein the first message includes a preamble and data, and is configured to transmit a second message to the terminal as feedback of the first message, wherein the second message includes at least one of a contention resolution identifier, an uplink grant, a cell radio network temporary identifier (C-RNTI), a timing advance value, a physical uplink control channel (PUCCH) resource indication, scheduling information for downlink transmission, a fallback indicator, or a backoff indicator. Effects of the invention

[0015] The apparatus and method according to various embodiments of the present disclosure enable data transmission to be completed more quickly by allowing a user device to access a network quickly.

[0016] The effects obtainable from the present disclosure are not limited to those mentioned above, and other unmentioned effects will be clearly understood by those skilled in the art to which the present disclosure belongs from the description below. Brief explanation of the drawing

[0018] Figure 1 illustrates a contention-based four-step random access process of the prior art. FIG. 2 illustrates a two-step random access process according to an exemplary embodiment of the present disclosure. FIG. 3 illustrates a method in a UE for signal transmission according to an exemplary embodiment of the present disclosure. FIG. 4 illustrates an exemplary diagram of a UCI modulation symbol mapping method 1 according to an exemplary embodiment of the present disclosure. FIG. 5 illustrates an exemplary diagram of a UCI modulation symbol mapping method 2 according to an exemplary embodiment of the present disclosure. FIG. 6 illustrates an exemplary diagram of a UCI modulation symbol mapping method 3 according to an exemplary embodiment of the present disclosure. FIG. 7 illustrates a structural block diagram of a UE according to an exemplary embodiment of the present disclosure. FIG. 8 illustrates a method at a base station for signal transmission according to an exemplary embodiment of the present disclosure. FIG. 9 illustrates a structural block diagram of a base station according to an exemplary embodiment of the present disclosure. Figure 10 illustrates an exemplary diagram for determining the RE mapping method according to the DMRS configuration. FIG. 11 illustrates an exemplary diagram of in-slot frequency hopping according to an exemplary embodiment of the present disclosure. FIG. 12 illustrates an exemplary diagram of inter-slot frequency hopping according to an exemplary embodiment of the present disclosure. Specific details for implementing the invention

[0019] Embodiments of the present disclosure are described in detail below and illustrated in the accompanying drawings, and identical or similar reference numerals throughout indicate identical or similar elements having identical or similar functions. The embodiments described below with reference to the drawings are merely examples for explaining the present disclosure and should not be construed as limiting the present disclosure.

[0020] A person skilled in the art will understand that, unless specifically stated otherwise, singular terms used in the specification of this disclosure may also include plural forms. It should also be understood that the word “comprising” as used in the specification of this disclosure indicates the presence of features, integers, steps, actions, elements and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, actions, elements, components, and / or combinations thereof. It should also be understood that when an element is referred to as “connected” or “combined” with another element, the element may be directly connected to or combined with the other element, or intermediate elements may exist. Additionally, “connected” or “combined” as used in the specification of this disclosure may include being wirelessly connected or wirelessly combined. As used in the specification of this disclosure, the phrase “and / or” includes all or any one of one or more related enumerated items and all combinations thereof.

[0021] Unless otherwise defined, it will be understood by a person skilled in the art that all terms used in the specification of this disclosure (including technical and scientific terms) have the same meaning as generally understood by a person skilled in the art to which this disclosure pertains. Furthermore, it should be understood that terms such as those defined in general dictionaries have meanings consistent with their meanings in the context of the prior art, and that they should not be described in an ideal or overly formal sense unless specifically defined in the specification of this disclosure.

[0022] A person skilled in the art will understand that the terms “UE (user equipment)” and “terminal” as used in the specification of this disclosure include not only wireless signal receiver devices that are devices having only a wireless signal receiver without a transmission function, but also devices having receiving and transmitting hardware that are devices capable of performing bidirectional communication through a bidirectional communication link. Such devices may include cellular or other communication devices having a single-line display or a multi-line display, or cellular or other communication devices without a multi-line display; personal communication service (PCS) capable of combining voice, data processing, fax and / or data communication functions; personal digital assistant (PDA) that may include a radio frequency (RF) receiver, a pager, internet / intranet access, a web browser, a notepad, a calendar, and / or a global positioning system (GPS) receiver; and conventional laptop and / or palmtop computers or other devices that may be conventional laptop and / or palmtop computers or other devices having and / or including an RF receiver. As used in the specification of this disclosure, “terminal” and “terminal device” may be portable, mobile, installed on a means of transport (air, sea and / or land), or adjusted and / or configured to operate locally, and / or operated in a distributed form at other locations on the ground and / or in the air. As used in the specification of this disclosure, “UE” and “terminal” may be communication terminals, internet terminals, PDAs, mobile internet devices (MIDs) and / or music / video playback terminals such as mobile phones having music / video playback functions, or smart TVs, set-top boxes and other devices.

[0023] In the present disclosure, the time unit may be an OFDM symbol, an OFDM symbol group (composed of multiple OFDM symbols), a time slot, a time slot group (composed of multiple time slots), a subframe, a subframe group (composed of multiple subframes), a system frame, a system frame group (composed of multiple system frames), or an absolute time unit such as 10 ms, 1 ms, 1 s, etc. The time unit may be a combination of various units such as N1 time slots + N2 OFDM symbols.

[0024] In the present disclosure, the frequency domain unit may be a subcarrier, a subcarrier group (composed of multiple subcarriers), a resource block (RB) which may also be referred to as a physical resource block (PRB), a resource block group (composed of multiple resource blocks (RB)), a bandwidth part (BWP), a bandwidth part group (composed of multiple bandwidth parts (BWP)), a band / carrier, a band group / carrier group, or an absolute frequency domain unit such as 1 Hz, 1 kHz, etc. The frequency domain unit may be a combination of various units such as M1 PRBs + M2 subcarriers.

[0025] In order to make the purpose, technical means, and advantages of the present disclosure clearer, the present disclosure will be described in more detail below with reference to the accompanying drawings.

[0026] To aid in understanding the present disclosure, the technical solutions of the present disclosure will be further explained in an interactive mode between a UE and a base station, along with specific application scenarios.

[0027] To achieve faster signal transmission and reception, the present disclosure proposes transmitting a random access preamble together with a data portion (indicated as a "first message") and then searching a downlink channel for feedback from a network device (indicated as a "second message"), and also proposes solutions for a method of configuring information of the first message and the second message and a method of proceeding based on feedback from the network device.

[0028] Transmission in a wireless communication system includes transmission from a base station (e.g., gNB) to a UE, where the corresponding time slot is called a downlink time slot (referred to as downlink transmission); and transmission from a UE to a base station, where the corresponding time slot is called an uplink time slot (referred to as uplink transmission).

[0029] In downlink communication of a wireless communication system, the system periodically transmits synchronization signals and broadcast channels to the UE via synchronization signal blocks (synchronization signal / PBCH blocks, SSB), and this periodicity is referred to as synchronization signal block periodicity (SSB periodicity) or SSB burst periodicity. Simultaneously, the base station can configure a random access configuration period (physical random access channel (PRACH) configuration period). A specific number of random access transmission opportunities (also called random access opportunities, PRACH transmission opportunities, or ROs) are configured within the period, and all SSBs can be mapped to the corresponding RO within a mapping period (a specific time length).

[0030] In NR (new radio) communication systems, the performance of random access directly impacts the user experience before radio resource control (RRC) is set up, as is the case in the random access process. In conventional radio communication systems such as LTE and LTE-A (LTE-advanced), the random access process applies to various scenarios, including initial connection establishment, cell handover, uplink connection re-establishment, and RRC connection re-establishment. Depending on whether a UE exclusively occupies preamble resources, the random access process is classified into contention-based random access and contention-free random access. In contention-based random access, each UE selects a preamble from the same preamble resources when attempting to establish an uplink connection. It is possible for multiple UEs to select the same preamble and transmit it to the base station. Therefore, contention resolution mechanisms are an important research direction in random access. Methods to reduce the likelihood of contention and to quickly resolve existing contention are key indicators affecting the performance of random access.

[0032] The contention-based random access process in LTE-A is divided into four stages as illustrated in FIG. 1. In Stage 1, the UE randomly selects a preamble from a preamble resource pool and transmits it to the base station. The base station performs correlation detection on the received signal to identify the preamble transmitted by the UE. In Stage 2, the base station transmits a random access response (RAR) to the UE, which includes a random access preamble identifier, a timing advance command determined by the delay estimation between the UE and the base station, a temporary cell-radio network temporary identifier (C-RNTI), and time-frequency resources allocated for the UE's next uplink transmission. In Stage 3, the UE transmits a third message (Msg3) to the base station based on the information in the RAR. Msg3 includes information such as a UE identifier unique to the UE and used for contention resolution, and an RRC connection request. In Stage 4, the base station transmits a contention resolution identifier to the UE, which includes the UE identifier of the UE that won the contention resolution. After the UE detects its own identifier, the UE upgrades the temporary C-RNTI to the C-RNTI, sends an ACK signal to the base station to complete the random access process, and waits for scheduling by the base station. Otherwise, the UE will start a new random access process after a specific delay.

[0033] In the case of a non-contention random access process, the base station knows the UE ID, so it can assign a preamble to the UE. Therefore, when transmitting the preamble, the UE uses the assigned preamble without needing to randomly select one. After detecting the assigned preamble, the base station transmits the corresponding random access response, which includes information such as timing advances and uplink resource allocation. Upon receiving the random access response, the UE considers uplink synchronization complete and waits for further scheduling by the base station. Thus, the non-contention random access process involves only two steps: Step 1, transmitting the preamble, and Step 2, transmitting the random access response.

[0034] The random access process in LTE is applicable to the following scenarios.

[0035] 1. Initial access to RRC_IDLE

[0036] 2. Re-establish RRC connection

[0037] 3. Cell Handover

[0038] 4. In the RRC connection state, downlink data arrives and a random access process is requested (if the uplink is in a de-synchronous state)

[0039] 5. In an RRC connection state, uplink data arrives and a random access process is requested (when the uplink is asynchronous or none of the PUCCH resources are allocated to the scheduling request)

[0040] 6. Positioning

[0042] However, for future communication systems, for UEs that need to access the network quickly or have only a small amount of data to be transmitted to a base station, implementing RRC establishment, resource scheduling requests, and then data transmission in 4-step random access is not an efficient transmission method. A method that allows for faster network access or enables the UE to transmit data more efficiently is desirable.

[0044] FIG. 2 schematically illustrates a two-step random access process according to an exemplary embodiment of the present disclosure.

[0045] First, the base station may transmit system information (SI), DCI (downlink control information), upper layer control information (such as an RRC configuration message), and configuration information for signal transmission and reception according to the present disclosure (called a two-stage random access process or a two-stage RACH process) to the UE through a downlink channel (such as a PDCCH, PDSCH, or a physical downlink broadcast channel, PBCH) in a handover command message.

[0046] As illustrated in FIG. 2, in 201, the UE obtains configuration information, determines resource configuration for transmitting a first message of two-stage random access according to the configuration information, prepares the first message, and transmits the first message through an uplink channel.

[0047] In 202, the base station receives a first message, detects a preamble of the first message and / or decodes the data portion of the first message, prepares a second message as feedback to the first message, and transmits the second message through a downlink channel.

[0048] In 203, the UE detects a second message from the base station, and upon detection of the second message, performs a subsequent operation, for example, retransmitting the first message, retransmitting the data of the first message, transmitting new data, or successfully completing the transmission.

[0049] Hereinafter, a flowchart of a method in a UE for signal transmission according to an exemplary embodiment of the present disclosure will be described in detail with reference to FIG. 3.

[0051] FIG. 3 schematically illustrates a flowchart of a method (300) in a UE for signal transmission according to an exemplary embodiment of the present disclosure.

[0052] As illustrated in FIG. 3, the method (300) includes steps S301 to S303.

[0053] In step S301, the UE can obtain configuration information for a two-step random access transmission.

[0054] In step S302, the UE can determine the resource configuration for transmitting the first message of the two-stage random access transmission based on the configuration information for the two-stage random access transmission obtained.

[0055] In step S303, the UE can transmit a first message to the base station according to the determined resource configuration.

[0057] Specifically, the configuration information for 2-stage random access transmission may include at least one of the following (1) to (7).

[0058] (1) A set of time-frequency resources for two-stage random access transmission comprising at least one of (1-1) to (1-3).

[0059] (1-1) Time-frequency resources for transmitting the preamble of 2-stage random access (2-stage RACH RO)

[0060] (1-2) Time-frequency resources for transmitting 2-stage random access PUSCH (2-stage RACH PUSCH)

[0061] (1-3) DMRS time-frequency resources of time-frequency resources (2-stage RACH PUSCH) for transmitting 2-stage random access PUSCH

[0062] (2) Mapping relationship between two-stage random access time-frequency resources and downlink beams

[0063] (3) Resource pool of X-RNTIs (X-radio network temporary identifiers) for 2-stage random access transmission

[0064] (4) Configuration of search spaces and / or configuration of control resources for searching feedback of two-stage random access transmissions

[0065] (5) Maximum number of transmissions (N_max) for 2-stage random access transmission

[0066] (5-1) In particular, the BETA value can be configured to represent the ratio of N_max to the maximum number of transmissions (N_max_4) for 4-stage random access transmissions. That is, N_max = BETA * N_max_4

[0067] (6) Maximum transmission time (T_time) for 2-stage random access transmission

[0068] (7) W available PUCCH resources configuration (e.g., W=16, N=4 bits used in the second message to indicate that the UE should provide feedback on the PUCCH resources after the second message is received), W and N are positive integers

[0070] In an exemplary embodiment, the UE may obtain configuration information for a two-stage random access transmission from a system broadcast message (including a primary broadcast message, remaining minimum system information (RMSI) and / or other broadcast message (OSI)), or downlink control channel information, or upper layer control signaling information, or a base station handover command message received through the downlink channel.

[0072] In an exemplary embodiment, the UE may also obtain configuration information for other random access transmissions, such as configuration information for a 4-stage random access transmission. In this case, the UE may determine whether to perform a 2-stage random access transmission or a 4-stage random access transmission by one of the following operations (1) to (6).

[0073] (1) Depending on the random access trigger event, the UE decides whether to perform a 2-stage random access transfer or a 4-stage random access transfer. For example, if the trigger event is a schedule request, the UE performs a 2-stage random access transfer, and if the trigger event is another event such as an uplink being out of sync, the UE performs a 4-stage random access transfer.

[0074] (2) Depending on the service type, the UE decides whether to perform a 2-stage random access transmission or a 4-stage random access transmission. For example, if the service type is ultra-reliable low-latency communication (URLC), the UE performs a 2-stage random access transmission, and if the service type is other types such as enhanced mobile broadband (eMBB) or mass machine type communication (mMTC), the UE performs a 4-stage random access transmission.

[0075] (3) The UE decides whether to perform a 2-stage random access transfer or a 4-stage random access transfer based on the measured PL and / or RSRP. For example, if the measured PL and / or RSRP is higher (or not lower) than a predefined or configured threshold T1, the UE performs a 2-stage random access transfer, and if the measured PL and / or RSRP is not higher (or lower) than a predefined or configured threshold T2, the UE performs a 4-stage random access transfer, and in particular, T1 and T2 are the same threshold.

[0076] (4) UE always prefers to perform 2-step random access transmission.

[0077] (5) The UE randomly selects either a 2-stage random access transmission or a 4-stage random access transmission.

[0078] (6) In response to receiving a notification from a system message (or DCI or higher-level control information, or handover command message), the UE decides whether to perform a 2-stage random access transfer or a 4-stage random access transfer. For example, if the RMSI (or DCI, or RRC configuration, or handover command message) indicates that 2-stage random access is to be used, the UE performs a 2-stage random access transfer, and if not, the UE performs a 4-stage random access.

[0080] In an exemplary embodiment, if the UE decides to perform a two-step random access, step S302 is performed.

[0081] In an exemplary embodiment, the first message may include at least one of the following (1) to (3).

[0082] (1) Random access preamble (preamble)

[0083] (2) Data portion (PUSCH and / or DMRS), information transmitted via PUSCH may include at least one of the following (2-1) and (2-2).

[0084] (2-1) BSR and / or PHR

[0085] (2-1-1) In particular, BSR and / or PHR may be transmitted in the form of a medium access control (MAC) control element (CE) and / or a MAC protocol data unit (PDU).

[0086] (2-2) N bit UCI, for example, N can be 1 or 2, and the contents of the UCI can be at least one of (2-2-1) to (2-2-4).

[0087] (2-2-1) MCS display

[0088] (2-2-2) PUSCH transmission location indication. For example, the 2-step RACH PUSCH of the configuration information occupies two time units, but the UE selects one time unit for transmission (for example, if the UE's channel conditions are relatively good or the amount of data transmission is relatively small, the UE may select only one time unit for transmission to reduce power consumption), and then informs the network device with 2 bits of information whether the UE selects one of the two time units for transmission or both time units for transmission.

[0089] (2-2-3) Display of Channel Status Information Reference Signal (CSI-RS)

[0090] (2-2-4) Hybrid Automatic Repeat Request (HARQ) - ACK Feedback

[0091] (3) Other possible information that may be included in Msg3 of conventional 4-step random access, such as a UE ID that may be at least one of (3-1) to (3-3)

[0092] (3-1) C-RNTI

[0093] (3-2) CCCH SDU (Service-Temporary Mobile Subscriber Identity (S-TMSI), or a fixed random number such as an N (positive integer) bit random number, e.g., N=40

[0094] (3-3) User Plane Data

[0096] In an exemplary embodiment, the MCS used in PUSCH can be determined according to at least one of (1) and (2).

[0097] (1) Content included in the data portion. For example, there are two MCS settings (represented as MCS 0 to MCS 1). When BSR, PHR and other data are included, the UE selects a higher MCS, such as MCS 1, i.e., a larger modulation order and / or a larger coding rate, and when only one type of data (such as BSR) is included, the UE selects a lower MCS, such as MCS 0, i.e., a smaller modulation order and / or a smaller coding rate.

[0098] (2) Recently measured PL and / or RSRP. For example, if the measured PL is higher than (or not lower than) a predefined or configured threshold T1, the UE selects a higher MCS 1, i.e., a larger modulation order and / or a larger coding rate, and if the measured PL is not higher than (or lower than) a predefined or configured threshold T2, the UE selects a lower MCS, such as MCS O, i.e., a smaller modulation order and / or a smaller coding rate, and in particular, T1 and T2 may be the same threshold.

[0100] In an exemplary embodiment, the MCS indication may indicate the MCS configuration by one of the following (1) to (3).

[0101] (1) N-bit direct representation. For example, a 1-bit MCS representation (2 MCS configuration representation) represents the modulation and coding scheme used in PUSCH, and the 2 MCS configurations may be the first 2 selected from the existing complete MCS table or arbitrarily selected 2 MCS configurations.

[0102] (2) Different preamble groups. For example, preambles 0 to 31 of the configuration information received by the UE correspond to MCS O, and preambles 32 to 63 correspond to MCS 1. If the UE decides to use MCS O, the UE selects a preamble from preambles 0 to 31, and if the UE decides to use MCS 1, the UE selects a preamble from preambles 32 to 63.

[0103] (3) Different bit-level scrambling and / or interleaving groups. For example, in configuration information received by the UE, the step of reading from the 0th column of the interleaving corresponds to MCS 0, and the step of reading from the Nth column corresponds to MCS 1. If the UE decides to use MCS 0, the UE reads the encoded bits from the 0th column, and if the UE decides to use MCS 1, the UE reads the encoded bits from the Nth column.

[0105] In an exemplary embodiment, the UCI is modulated and encoded by at least one of the following operations (1) to (4).

[0106] (1) Encode O(positive integer) UCI ​​bits using RM codes or polarity codes.

[0107] (2) If the O(positive integer) UCI ​​bit is less than the first threshold, the 0(positive integer) UCI ​​bit is encoded using the RM codes of (16, O). Or, if the O(positive integer) UCI ​​bit is not less than the second threshold, the 0(positive integer) UCI ​​bit is encoded using the RM codes of (32, O).

[0108] (3) If the O(positive integer) UCI ​​bit is less than the first threshold, the 0(positive integer) UCI ​​bit is encoded using RM codes. Or if the O(positive integer) UCI ​​bit is not less than the second threshold, the 0(positive integer) UCI ​​bit is encoded using polarity codes.

[0109] (4) Determine the modulation order of UCI according to the modulation order of PUSCH.

[0111] In an exemplary embodiment, the RE mapping method of the UCI may include at least one of (1) to (8).

[0112] (1) The modulated symbols of the UCI are mapped to available REs according to the frequency domain priority (or time domain priority) principle.

[0113] (2) When the modulated symbols of the UCI are smaller than the number of REs available in one time unit, the modulated symbols of the UCI are mapped to the REs in an equally spaced, discrete manner.

[0114] (3) If a number of modulated symbols in UCI is smaller than (or not larger than) a first threshold T1, the modulated symbols in PUSCH are directly punctured into the REs originally occupied by the modulated symbols in UCI, and no rate matching is performed on the REs in PUSCH, or if a number of modulated symbols is not smaller than (or larger than) a second threshold T2, rate matching is performed on the PUSCH data. In particular, T1 and T2 may be the same threshold.

[0115] (4) Modulated symbols of UCI are sequentially mapped from the first non-DMRS symbol to the OFDM symbol. FIG. 4 illustrates an exemplary method for mapping UCI modulated symbols, wherein the modulated symbols of UCI are sequentially mapped from the first non-DMRS symbol to the OFDM symbol, regardless of whether the DMRS pattern is located at the beginning or middle of the PUSCH symbol.

[0116] (5) Modulated symbols of UCI are sequentially mapped to OFDM symbols starting from the first non-DMRS symbol after (or before) the first DMRS symbol. In particular, when multiple DMRS symbols are arranged in succession, the modulated symbols of UCI are sequentially mapped to OFDM symbols starting from the first non-DMRS symbol after (or before) the last of the first consecutive multiple DMRS symbols. FIG. 5 illustrates another exemplary method of mapping UCI modulated symbols, wherein the mapping is performed sequentially after the first DMRS symbol.

[0117] (6) When the modulated symbols of the UCI occupy multiple time units, such as OFDM symbols, the modulated symbols of the UCI are sequentially mapped to OFDM symbols starting from the non-DMRS symbol closest to the first DMRS symbol. That is, they are sequentially mapped from the OFDM symbols of the previous non-DMRS symbol adjacent to the DMRS symbol to the OFDM symbols of the next non-DMRS symbol adjacent to the DMRS symbol. In particular, when the DMRS symbol is located at the beginning, the modulated symbols of the UCI are sequentially mapped to OFDM symbols starting from the next non-DMRS symbol adjacent to the DMRS symbol, as shown in FIG. 6.

[0118] (7) When multiple pieces of information are included in the UCI, the multiple pieces of information are arranged in a predefined order of priority. For example, the multiple pieces of information may include at least an MCS indication, a PUSCH transmission location indication, a CSI report, and a HARQ-ACK indication. In this case, the multiple pieces of information may be arranged such that, for example, the first is the MC, the second is the PUSCH transmission location indication, the third is the CSI report, and the last is the HARQ-ACK indication.

[0119] (8) In particular, when the UE has various different RE mapping schemes, the corresponding RE mapping schemes of the UCI may be selected based on different DMRS configurations (e.g., different DMRS types and / or different DMRS port indices or index groups). For example, if the configured DMRS is of type A (e.g., the DMRS symbol is not the first symbol of PUSCH), the UE sequentially maps UCI modulated symbols to OFDM symbols starting from the first non-DMRS symbol prior to the first DMRS symbol. If the configured DMRS is of type B (e.g., the DMRS symbol is the first symbol of PUSCH), the UE sequentially maps UCI modulated symbols to OFDM symbols starting from the first non-DMRS symbol as shown in FIG. 10.

[0121] The UE determines the resource location of the first message to be transmitted and the content of the first message to be transmitted, and transmits the first message after power control. When the UE transmits the data portion and the random access preamble of the first message simultaneously, the UE may first determine the transmission beam of the preamble and then set the transmission beam of the data portion to be identical to the transmission beam of the preamble. That is, the spatial domain transmission filter for transmitting the data portion is set according to the spatial domain transmission filter for transmitting the random access preamble.

[0123] Additionally, the method (300) includes steps S304 and S305.

[0124] In step S304, the UE can detect a second message from the base station as feedback to the first message.

[0125] In step S305, the UE performs a subsequent action based on the detection result.

[0127] In an exemplary embodiment, the UE may select a first set of available control resources and / or a search space of N time units after the last time unit in the first message as a starting position. The UE begins to search and detect a possible second message in the set of available control resources and / or search space within a random access response detection window having a length of W time units, and the UE determines M X-RNTIs to search and detect the possible second message (e.g., the determined X-RNTIs are used for descramble the CRC of the received PDCCH. If decoding is successful, it indicates that the correct PDCCH has been searched and detected, and if not, it indicates that the correct PDCCH has been searched and detected). The UE can determine the X-RNTI by the X-RNTI resource pool given in the configuration information of the network device, or by the determined resource information of the first transmitted message (including time location information and / or frequency domain location information and / or index information of the preamble), or by the determined content information of the first transmitted message (e.g., the transmitted C-RNTI), and M is a positive integer.

[0128] In an exemplary embodiment, M=1. That is, the UE determines one X-RNTI for searching for and detecting a second message that may be used as feedback for the first message.

[0129] In an exemplary implementation, if the UE includes a C-RNTI in the first message, the UE may use the C-RNTI included in the first message as an X-RNTI for detecting the second message of two-stage random access to search for and detect a possible second message.

[0130] In this implementation, when the UE detects the correct PDCCH, the first message is accurately received by the base station, and the UE performs a subsequent operation according to the information transmitted from the DCI obtained from the PDCCH.

[0132] Specifically, subsequent actions may include at least one of the following.

[0133] (1) When a UE detects that an uplink grant (UL grant) is being delivered from the DCI, the UE continues to transmit new data, and in particular, the transmission of new data may indicate the retransmission of other data. For example, when a UE has multiple HARQ processes, the UE may detect a HARQ process ID from the DCI, and then the UE may retransmit data of the detected HARQ process ID or transmit new data. In particular, when the UE transmits a frequency hopping indication from the detected DCI or upper layer configuration information (e.g., system information) and the frequency hopping indication is configured to be enabled, the UE interprets the time-frequency resource configuration of the uplink grant according to the frequency domain offset (or frequencyHoppingOffset, or frequency offset) and frequency hopping mode (in-slot or between-slot) configured in the detected DCI or upper layer configuration information (e.g., system information). In particular, when the UE transmits a BWP index and / or repeat indication from the detected DCI or upper-layer configuration information (e.g., system information), the UE transmits data for time-frequency resources indicated by the uplink grant in the indicated BWP and / or according to the indicated number of repeats and repetition method.

[0134] (2) When the UE detects that an N-bit PUCCH resource indication is transmitted from the DCI, the UE may include at least one step of receiving a second message and then providing feedback on the PUCCH resources.

[0136] If the UE fails to detect an accurate PDCCH in the detection window, the UE's first message is not accurately received by the base station, and subsequent actions performed by the UE may include at least one of the following actions.

[0137] (1) The UE falls back to the 4th stage random access process. Specifically, the UE falls back to retransmit the preamble (i.e., Msg1 of the 4th stage random access), and the UE performs resource selection for transmitting the random access preamble and subsequent feedback search according to the resource configuration of the 4th stage random access. Specifically, the UE may perform the following actions.

[0138] (1-1) The UE resets the random access preamble transfer counter to 0.

[0139] (1-2) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowable transfer count (for 2-stage random access or 4-stage random access) has not been exceeded and / or the preamble transfer timer has not expired, the UE falls back to the 4-stage random access process.

[0140] (2) The UE increments the random access preamble transfer counter by 1. Specifically, if the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE reports a random access problem or falls back to the 4-step random access process.

[0142] In another exemplary implementation, when the UE detects the correct PDCCH using X-RNTI, the UE performs subsequent actions based on the information transmitted from the DCI obtained from the PDCCH.

[0143] (1) When the UE detects that a contention resolution identifier is being transmitted from the DCI,

[0144] (1-1) If the detected contention resolution identifier exactly matches the UE ID uploaded by the UE, the first message is accurately received by the base station, and the UE performs subsequent actions according to the information transmitted from the DCI.

[0145] Specifically, subsequent actions may include at least one of the following actions.

[0146] (1-1-1) When the UE detects that an uplink grant is being delivered from the DCI, the UE continues to transmit new data. In particular, the transmission of new data may indicate the retransmission of other data. For example, when the UE has multiple HARQ processes, the UE may detect a HARQ process ID from the DCI, and then the UE may retransmit data of the detected HARQ process ID or transmit new data. In particular, when the UE transmits a frequency hopping indication from the detected DCI or upper-level configuration information (e.g., system information) and when the frequency hopping indication is configured to be enabled, the UE follows the frequency domain offset (or frequencyHoppingOffset or frequency offset) and frequency hopping mode (in-slot or between-slot) configured in the uplink grant from the detected DCI or upper-level configuration information (e.g., system information). In particular, when the UE transmits a BWP index and / or iteration indication from the detected DCI or upper-level configuration information (e.g., system information), the UE transmits data regarding time-frequency resources indicated by the uplink grant according to the indicated BWP and / or the indicated number of iterations and iteration method. For example, when the UE ID included by the UE in the transmitted PUSCH is C-RNTI, and the UE detects that the DCI uses C-RNTI and detects the UL grant in the DCI, that is, when the UE considers that the preamble is correctly detected and the PUSCH is correctly detected and decoded, the UE may ignore the frequency hopping indication configuration (e.g., whether it is enabled, frequency domain offset, etc.) of the previous RRC configuration (e.g., UE-specific RRC configuration), and the UE follows the frequency hopping indication transmitted from the detected DCI or upper-level configuration information (e.g., system information).When the frequency hopping indication is configured to be enabled, the UE interprets the time-frequency resource configuration of the uplink grant based on the frequency domain offset (or frequencyHoppingOffset or frequency offset) and frequency hopping mode (in-slot or inter-slot) configured in the detected DCI or upper-level configuration information (e.g., system information). In particular, when the UE transmits the BWP index and / or iteration indication in the detected DCI or upper-level configuration information (e.g., system information), the UE transmits data regarding the time-frequency resources indicated by the uplink grant based on the indicated BWP and / or the indicated number of iterations and iteration method.

[0147] (1-1-2) When the UE detects that a temporary C-RNTI is being transmitted from the DCI, the UE sets the temporary C-RNTI as the C-RNTI or ignores the temporary C-RNTI.

[0148] (1-1-3) When the UE detects that a timing advance value is transmitted from the DCI, the UE calculates the amount of timing advance required by the subsequent uplink transmission based on the timing advance value.

[0149] (1-1-4) When the UE detects that an N-bit PUCCH resource indication is transmitted from the DCI, the UE may include at least one step of feeding back an ACK for the PUCCH resources after receiving the second message.

[0150] (1-2) If the detected combination resolution identifier does not match the UE ID uploaded by the UE, the first message is not received correctly by the base station, and the UE can perform at least one of the following actions.

[0151] (1-2-1) The UE stops another possible second message detection operation in the detection window.

[0152] (1-2-2) The UE falls back to the 4th stage random access process. Specifically, the UE falls back to retransmit the preamble (i.e., Msg1 of the 4th stage random access), and the UE performs resource selection for transmitting the random access preamble and subsequent feedback search according to the resource configuration of the 4th stage random access. Specifically, the UE may perform at least one of the following actions.

[0153] (1-2-2-1) The UE resets the random access preamble transfer counter to 0.

[0154] (1-2-2-2) The UE increments the random access preamble transfer counter by 1. (For 2-stage random access or 4-stage random access) If the configured maximum allowable transfer count has not been exceeded and / or the preamble transfer timer has not expired, the UE performs at least one of the actions to fall back to the 4-stage random access process.

[0155] (1-2-3) The UE increments the random access preamble transfer counter by 1. Specifically, if the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer, and if the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE reports a random access issue or falls back to the 4-step random access process.

[0156] (1-2-4) The UE continues to detect other possible second messages in the detection window.

[0157] (2) When the UE detects that scheduling information for downlink transmission is transmitted from the DCI, the UE receives a PDSCH according to the scheduling information, and the PDSCH may include at least one of the following.

[0158] (2-1) One or more detected random access preamble indices

[0159] (2-1-1) If the UE determines that the detected random access preamble index matches the preamble index transmitted by the UE in the first message, the UE detects that the PDSCH contains one or more random access responses (RAR).

[0160] (2-1-1-1) If one or more random access responses transmit a contention resolution identifier, and the detected contention resolution identifier exactly matches the UE ID uploaded by the UE, the first message is accurately received by the network device, and the UE performs subsequent actions according to the information transmitted from the RAR.

[0161] (2-1-2) Specifically, the subsequent action may include at least one of the following.

[0162] (2-1-2-1) When the UE detects that an uplink (UL) grant is being delivered from the DCI, the UE continues to transmit new data. In particular, the transmission of new data may indicate the retransmission of other data. For example, when the UE has multiple HARQ processes, the UE may detect a HARQ process ID from the DCI, and subsequently, the UE may retransmit data for the detected HARQ process ID or transmit new data. In particular, when the UE transmits a frequency hopping indication from the detected DCI or upper-level configuration information (e.g., system information) and the frequency hopping indication is configured to be enabled, the UE interprets the time-frequency resource configuration of the uplink grant based on the frequency domain offset (or frequencyHoppingOffset, or frequency offset) and frequency hopping mode (in-slot or between-slot) configured in the detected DCI or upper-level configuration information (e.g., system information). In particular, when the UE transmits a BWP index and / or iteration indication from the detected DCI or upper-level configuration information (e.g., system information), the UE transmits data for time-frequency resources indicated by the uplink grant according to the indicated BWP and / or the indicated number of iterations and iteration methods. For example, when the UE ID included by the UE in the transmitted PUSCH is a C-RNTI, and the UE detects a matching RAP ID, detects a UL grant in the RAR, and has a matching contention resolution ID, that is, when the UE considers that the preamble is correctly detected and the PUSCH is correctly detected and decoded, the UE may ignore the frequency hopping indication configuration (e.g., whether it is enabled, frequency domain offset, etc.) of the previous RRC configuration (e.g., UE-specific RRC configuration), and the UE follows the frequency hopping indication transmitted from the detected DCI or upper-level configuration information (e.g., system information).When the frequency hopping indication is configured to be enabled, the UE interprets the time-frequency resource configuration of the uplink grant based on the frequency domain offset (or frequencyHoppingOffset or frequency offset) and frequency hopping mode (in-slot or inter-slot) configured in the detected DCI or upper-level configuration information (e.g., system information). In particular, when the UE transmits the BWP index and / or iteration indication in the detected DCI or upper-level configuration information (e.g., system information), the UE transmits data regarding the time-frequency resources indicated by the uplink grant based on the indicated BWP and / or the indicated number of iterations and iteration method.

[0163] (2-1-2-2) If the UE detects that a temporary C-RNTI is being transmitted from the DCI, the UE sets the temporary C-RNTI as the C-RNTI or ignores the temporary C-RNTI.

[0164] (2-1-2-3) When the UE detects that a timing advance value is transmitted from the DCI, the UE calculates the amount of timing advance required by the subsequent uplink transmission based on the timing advance value.

[0165] (2-1-2-4) When the UE detects that an N-bit PUCCH resource indication is transmitted from the DCI, the UE feeds back an ACK for the corresponding PUCCH resources after the second message is received.

[0166] (3) If a contention resolution identifier detected in one or more RARs does not match a UE ID uploaded by the UE, the first message is not received correctly by the base station, and the UE can perform at least one of the following actions.

[0167] (3-1) The UE stops another possible second message detection operation in the detection window.

[0168] (3-2) The UE falls back to the 4th stage random access process. Specifically, the UE falls back to retransmit the preamble (i.e., Msg1 of the 4th stage random access), and the UE performs resource selection for transmitting the random access preamble and subsequent feedback search according to the resource configuration of the 4th stage random access. Specifically, the UE may perform at least one of the following actions.

[0169] (3-2-1) The UE resets the random access preamble transfer counter to 0.

[0170] (3-2-2) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowed transfer count (for 2-stage random access or 4-stage random access) has not been exceeded and / or the preamble transfer timer has not expired, the UE falls back to the 4-stage random access process.

[0171] (3-3) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE reports a random access issue or falls back to the 4-step random access process.

[0172] (3-4) The UE continues to detect other possible second messages in the detection window.

[0173] (4) If a contention resolution identifier is not detected in one or more RARs (and / or if a pre-configured value, such as all 0s or all 1s, indicating no contention resolution identifier is detected in one or more RARs), the UE considers that the transmitted preamble is detected but the data part is not detected correctly, and the UE may perform at least one of the following actions.

[0174] (4-1) The UE stops detecting other possible second messages in the detection window.

[0175] (4-2) The UE falls back to a 4-step random access process.

[0176] (5) When it is detected that an uplink grant is being transmitted from the RAR, the UE uses the uplink grant to (re)transmit the data portion of the first message (i.e., Msg3 of the 4th level random access). In particular, when the UE detects that a frequency hopping indication is being transmitted from the DCI or RAR or upper-level configuration information (e.g., system information), and the frequency hopping indication is configured to be enabled, the UE is within the uplink usage rights according to the detected DCI or RAR, or is within the frequency domain offset (or frequency offset) and frequency hopping mode (within the time slot or between the time slots) configured in the upper-level configuration information (e.g., system information). For example, in the example illustrated in FIG. 10, the UE ID included by the UE in the transmitted PUSCH is C-RNTI, and the UE detects a matching RAR ID, detects a UL Grant in the RAR, and does not have a contention resolution ID, that is, when the UE considers that the preamble is correctly detected and the PUSCH is not correctly detected and decoded, the UE may ignore the frequency hopping indication configuration (e.g., whether it is enabled, frequency domain offset, etc.) of the previous RRC configuration (e.g., UE-specific RRC configuration), and the UE transmits from the time-frequency resources indicated in the corresponding UL Grant according to the frequency hopping indication conveyed from the DCI or RAR or higher-level configuration information (e.g., system information). As illustrated in the left diagram of FIG. 11, when frequency hopping is not enabled, the UE interprets the time-frequency resource configuration as transmitting signals in time-domain OFDM symbols 0 through 5 and frequency-domain PRB 1 through PRB 3.As illustrated in the right diagram of FIG. 11, when frequency hopping is enabled and the frequency domain offset is 1 / 2 of the BWP size, the UE interprets the time-frequency resource configuration as a first hop transmitting signals in the first three OFDM symbols and PRB 1 to PRB 3, and a second hop transmitting signals in OFDM symbols 3 to OFDM symbols 5 and PRB 13 to PRB 15.

[0177] (6) When the transmission is a multi-slot transmission, frequency hopping between slots is configured (as shown in FIG. 12), and the UE interprets the time-frequency resource configuration as a first hop transmitting signals in OFDM symbols 0 to OFDM 5 and PRB 1 to PRB 3 of the first time slot and a second hop transmitting signals in OFDM symbols 0 to OFDM 5 and PRB 13 to PRB 15 of the second time slot.

[0178] (6-1) In particular, when a UE transmits a BWP index and / or repeat indication in a detected DCI or upper layer configuration information (e.g., system information), the UE transmits data for time-frequency resources indicated by an uplink grant according to the indicated BWP and / or the indicated number of repeats and repeating method.

[0179] (7) When a temporary C-RNTI is detected being transmitted from RAR, the UE uses the temporary C-RNTI or X-RNTI to search for the subsequent retransmission PDCCH of Msg3 and / or the PDCCH of Msg4.

[0180] (8) When a timing advance value is detected being transmitted from the RAR, the UE calculates the amount of timing advance required for subsequent uplink transmission (including Msg3) based on the timing advance value.

[0181] (8-1) The UE falls back to retransmit the preamble (Msg1 of the 4th stage random access), and the UE performs resource selection for subsequent feedback search and random access preamble transmission according to the resource configuration of the 4th stage random access. In particular, the UE may perform at least one of the following actions.

[0182] (8-1-1) The UE resets the random access preamble transfer counter to 0.

[0183] (8-1-2) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowed transfer count (for 2-stage random access or 4-stage random access) has not been exceeded and / or the preamble transfer timer has not expired, the UE falls back to the 4-stage random access process.

[0184] (8-1-3) The UE increments the random access preamble transfer counter by 1. Specifically, if the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer, and if the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE reports a random access issue or falls back to the 4-step random access process.

[0185] (8-1-4) The UE continues to detect other possible second messages in the detection window.

[0187] If the UE determines that the detected random access preamble index does not match the preamble index transmitted by the UE in the first message, the UE may perform at least one of the following actions.

[0188] (1) The UE stops detecting other possible second messages in the detection window.

[0189] (2) The UE falls back to the 4th stage random access process. Specifically, the UE falls back to retransmit the preamble (i.e., Msg1 of the 4th stage random access), and the UE performs resource selection for subsequent feedback search and random access preamble transmission according to the resource configuration of the 4th stage random access.

[0190] (3) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE reports a random access problem or falls back to the 4-step random access process.

[0191] (4) The UE continues to detect other possible second messages in the detection window.

[0193] If the UE fails to detect an accurate PDCCH in the entire detection window using X-RNTI, the UE may perform at least one of the following actions.

[0194] (1) The UE falls back to the 4th stage random access process. Specifically, the UE falls back to retransmit the preamble (i.e., Msg1 of the 4th stage random access), and the UE performs resource selection for subsequent feedback search and random access preamble transmission according to the resource configuration of the 4th stage random access.

[0195] (2) The UE increments the random access preamble transfer counter by 1. If the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer timer has expired, the UE may perform at least one of the steps of reporting a random access problem or falling back to a 4-step random access process.

[0197] In another exemplary embodiment, M=2, i.e., the UE determines that two X-RNTIs are used to search for possible second messages, namely, one X-RNTI represented as X-RNTI-2 (for detecting second messages of 2-level random access) and another X-RNTI represented as X-RNTI-4 (for detecting second messages of 4-level random access).

[0198] Since the processing method of the UE using X-RNTI-2 to search for a possible second message is the same as the processing method of the UE when M=1, the details will not be described again here.

[0199] If the UE fails to detect the correct PDCCH using X-RNTI-2, fails to detect a matching contention resolution identifier, or fails to detect a matching random access preamble index, the UE may switch to using X-RNTI-4 to detect a possible second message. Since the method of processing the UE using X-RNTI-4 to search for a possible second message is the same as the method of searching for a random access response in a conventional four-step random access process, the details will not be described again here.

[0201] In the retrieved second message (i.e., the corresponding PDCCH and / or PDSCH), the UE can detect a Fallback Indicator (FI) in the MAC subheader, including, for example, an N (e.g., N=1, N=2) bit fallback indicator.

[0202] (1) When N=1, if the UE detects FI=1 (or 0 or True or enabled), the UE falls back to the 4-stage random access process, otherwise the UE continues the 2-stage random access process.

[0203] (2) FI represents 2^N (2 to the power of N) possible values ​​(e.g., FI_0, FI_1, FI_i; FI_2^N). When the FI of the network configuration received by the UE is set to FI_i, the UE randomly selects a number X from 0 to 1. If X is greater than FI_i (i.e. not smaller), the UE continues the 2-step random access process. If X is not greater than FI_i (i.e. smaller), the UE falls back to the 4-step random access process.

[0205] If the UE detects a backoff indicator (BI) in the second message (i.e., the corresponding PDCCH and / or PDSCH), and the UE needs to fall back to Level 4 random access, the UE may ignore the BI, or the UE may generate a time unit of random number T. If T > X, the UE transmits Msg1 in Level 4 random access using the first available RO after T. If the UE needs to continue to Level 2 random access, the UE may ignore the BI, or the UE may generate a time unit of random number T. If T > X, the UE transmits the first message in Level 2 random access using the first available Level 2 random access time-frequency resource after T.

[0207] FIG. 7 schematically illustrates a schematic structural diagram of a UE according to an embodiment of the present disclosure.

[0208] The UE (700) can be used to perform the method (300) described with reference to FIG. 3.

[0209] As illustrated in FIG. 7, the UE (700) comprises a processing unit or processor (701) which may be a single unit or a combination of multiple units for performing different steps of the method, and a memory (703) in which computer-executable instructions are stored, and when said instructions are executed by the processor (1102), the UE (700) causes the method (300) to perform. For brevity, the specification of the present disclosure will only describe the schematic structure of the UE according to an exemplary embodiment of the present disclosure, and details described above in the method (300) with reference to FIG. 3 will be omitted.

[0210] The above commands cause the UE (700) to perform the following operations when executed by the processor (701).

[0211] The UE (700) obtains configuration information for a 2-stage random access transmission.

[0212] The UE (700) determines a resource configuration for transmitting a first message of a two-stage random access transmission containing a preamble and / or data based on the configuration information for the acquired two-stage random access transmission.

[0213] The UE (700) transmits a first message to the base station according to the determined resource configuration.

[0214] The UE (700) detects a second message from the base station as feedback to the first message.

[0215] The UE (700) performs subsequent actions based on the detection result.

[0217] In an exemplary embodiment, the second message includes at least one of the following.

[0218] (1) Contention resolution identifier

[0219] (2) Uplink Grant

[0220] (3) Temporary C-RNTI

[0221] (4) Timing advance value

[0222] (5) Display PUCCH resources

[0223] (6) Scheduling information for downlink transmission

[0224] (7) Fallback indicator

[0225] (8) Backoff indicator

[0227] In an exemplary embodiment, the data includes PUSCH and / or DMRS.

[0228] Information transmitted via PUSCH includes at least one of the following.

[0229] (1) BSR and / or PHR

[0230] (2) UCI

[0231] (3) UE ID including C-RNTI and / or CCCH SDU

[0232] (4) At least one of the user planar data

[0234] In an exemplary embodiment, the UCI includes at least one of the following.

[0235] (1) MCS indication to indicate the modulation and coding scheme (MCS) used to transmit PUSCH

[0236] (2) PUSCH transmission location display

[0238] In an exemplary embodiment, the MCS used to transmit PUSCH is determined according to at least one of the following.

[0239] (1) Contents included in the data

[0240] (2) Latest measured PL and / or RSRP

[0242] In an exemplary embodiment, the MCS indication represents the MCS configuration by one of the following.

[0243] (1) N (positive integer) bit direct representation

[0244] (2) Different preamble groups

[0245] (3) Different bit-level scrambling and / or interleaving groups

[0247] In an exemplary embodiment, the UCI is modulated and encoded by at least one of the following operations.

[0248] (1) O(positive integer) UCI ​​bit encoding with RM code or polarity code.

[0249] (2) If the O UCI bit is less than the first threshold, the O UCI bit is encoded with the RM code of (16, O). Or, if the O UCI bit is not less than the second threshold, the O UCI bit is encoded with the RM code of (32, O).

[0250] (3) If the O UCI bit is less than the first threshold, the O UCI bit is encoded with RM code. Or if the O UCI bit is not less than the second threshold, the O UCI bit is encoded with polarity code.

[0251] (4) Determine the modulation order of UCI according to the modulation order of PUSCH.

[0253] In an exemplary embodiment, the resource element (RE) mapping method of the UCI includes at least one of the following.

[0254] (1) The modulated symbols of the UCI are mapped to available REs according to the time domain priority or frequency domain priority principle.

[0255] (2) When the number of modulated symbols in UCI is less than the number of REs available in one time unit, the modulated symbols in UCI are mapped to REs in an evenly spaced separation manner.

[0256] (3) When the number of modulated symbols in UCI is less than the first threshold, no rate matching is performed on the REs of PUSCH, and the modulated symbols of PUSCH are directly punctured on the REs that the modulated symbols of UCI originally occupied. When the number of modulated symbols is not less than the second threshold, rate matching is performed on the PUSCH data.

[0257] (4) The modulated symbols of the UCI are sequentially mapped from the first non-DMRS symbol to the orthogonal frequency division multiplexing (OFDM) symbols.

[0258] (5) The modulated symbols of the UCI are sequentially mapped to OFDM symbols from the first non-DMRS symbol after or before the first DMRS symbol.

[0259] (6) When the modulated symbols of the UCI occupy multiple OFDM symbols, the modulated symbols of the UCI are mapped sequentially to the OFDM symbols, starting from the non-DMRS symbol closest to the first DMRS symbol.

[0260] (7) When multiple pieces of information are included in the UCI, the multiple pieces of information are arranged in a predefined order of priority.

[0262] In an exemplary embodiment, when the commands are executed by the processor (701), the UE (700) further obtains configuration information for a 4-stage random access transmission and determines whether to choose to perform a 2-stage random access transmission or a 4-stage random access transmission by at least one of the following operations.

[0263] (1) The UE decides whether to perform a 2-step random access transfer or a 4-step random access transfer according to at least one of (1-1) to (1-3) below.

[0264] (1-1) Random access trigger event

[0265] (1-2) Service Types

[0266] (1-3) Measured PL and / or RSRP

[0267] (2) UE always prefers to perform 2-step random access transmission.

[0268] (3) The UE randomly selects a 2-stage random access transmission or a 4-stage random access transmission.

[0269] (4) In response to receiving a signal from the base station, the UE decides whether to perform a 2-step random access transmission or a 4-step random access transmission.

[0271] In an exemplary embodiment, when the preamble and data are transmitted simultaneously in the first message, the UE determines the transmission beam of the preamble and sets the transmission beam of the data to be the same as the transmission beam of the preamble.

[0273] In an exemplary embodiment, the subsequent action performed according to the detected second message includes at least one of the following actions.

[0274] (1) When an uplink grant is detected, the UE continues the initial transmission of new data, retransmits the data of the first message, or falls back to the initial transmission of Msg3 in the 4th stage random access.

[0275] (2) When a temporary C-RNTI is detected, the UE sets the temporary C-RNTI as C-RNTI or ignores the temporary C-RNTI.

[0276] (3) When a timing advance value is detected, the UE calculates the amount of timing advance required for subsequent uplink transmission based on the timing advance value.

[0277] (4) When the UE detects a PUCCH resource indication, it feeds back an ACK for the PUCCH resources after receiving the second message.

[0278] (5) When a fallback indication is detected, the UE continues the 2-step random access process or falls back to the 4-step random access process according to the fallback indication.

[0280] In an exemplary embodiment, if the UE detects a second message using the C-RNTI or X-RNTI included in the first message and an accurate PDCCH is not detected in the detection window, the subsequent action includes at least one of the following actions.

[0281] (1) The UE falls back to a 4-step random access process.

[0282] (2) The UE increments the preamble transfer counter by 1. If the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the next 2-step random access transfer is performed. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer counter has expired, the UE reports a random access problem or falls back to the 4-step random access process.

[0284] In an exemplary embodiment, if the UE fails to detect an accurate PDCCH in the detection window, or if the UE fails to detect a matching contention resolution identifier, or if the UE fails to detect a matching preamble index, the subsequent action performed upon detection of the second message includes at least one of the following actions.

[0285] (1) The UE stops detecting other possible second messages in the detection window.

[0286] (2) The UE falls back to the 4-step random access process.

[0287] (3) The UE increments the preamble transfer counter by 1. If the configured maximum allowable transfer count is not exceeded and / or the preamble transfer timer has not expired, the UE performs the next 2-step random access transfer. If the configured maximum allowable transfer count is exceeded and / or the preamble transfer counter has expired, the UE reports a random access problem or falls back to the 4-step random access process.

[0288] (4) The UE continues to detect other possible second messages in the detection window.

[0290] In an exemplary embodiment, if a matching contention resolution identifier is not detected, the operation of stopping detection of another possible second message in the detection window and the operation of falling back to a four-step random access process include at least one of the following operations.

[0291] (1) When an uplink grant is detected, the UE uses the uplink grant to transmit or retransmit the data of the first message.

[0292] (2) If a temporary C-RNTI is detected, the UE uses the temporary C-RNTI or X-RNTI to retrieve the retransmitted PDCCH of the subsequent Msg3 and / or the PDCCH of Msg4.

[0293] (3) When a timing advance value is detected, the UE calculates the amount of timing advance required for subsequent uplink transmission based on the timing advance value.

[0294] (4) The UE falls back to a 4-step random access transmission and retransmits the preamble.

[0296] In an exemplary embodiment, the instructions cause the UE (700), when executed by the processor (701), to transition to a step of detecting a second message using an X-RNTI for detecting a second message of a 4-stage random access if the UE fails to detect an accurate PDCCH, fails to detect a matching contention resolution identifier, or fails to detect a matching random access preamble index using an X-RNTI for detecting a second message of a 2-stage random access.

[0298] Hereinafter, a flowchart of a method in a base station for signal transmission according to an exemplary embodiment of the present disclosure will be described in detail with reference to FIG. 8. For the sake of simplification, details of the method (300) in a UE for signal transmission will be omitted here.

[0299] As illustrated in FIG. 8, the method (800) includes steps S801 to S803.

[0300] In step S801, the base station transmits configuration information for a two-step random access transmission to the UE.

[0301] In an exemplary embodiment, the configuration information for a two-stage random access transmission may include at least one of the following.

[0302] (1) A set of time-frequency resources for two-stage random access transmission

[0303] (2) Mapping relationship between two-stage random access time-frequency resources and downlink beams

[0304] (3) Resource pool of X-RNTIs for 2-stage random access transmission

[0305] (4) Configuration of control resources and / or configuration of search spaces for searching feedback of two-stage random access transmissions

[0306] (5) Maximum number of transmissions for 2-stage random access transmission

[0307] (6) Maximum transmission time for 2-stage random access transmission

[0308] (7) Multiple available PUCCH resource configurations

[0310] In step S802, the base station receives a first message transmitted by the UE to the base station according to a resource configuration determined based on configuration information, detects the preamble of the first message and / or decodes the data portion, and prepares a second message as feedback to the first message.

[0311] In particular, the second message may include at least one of the following.

[0312] (1) Contention resolution identifier

[0313] (2) Uplink Grant

[0314] (3) Temporary C-RNTI

[0315] (4) Timing advance value

[0316] (5) PUCCH resource indication to indicate to the UE to provide feedback for the corresponding PUCCH resource after receiving the second message.

[0317] (6) Scheduling information for downlink transmission

[0318] (7) Fallback indicator

[0319] (8) It may include at least one backoff indicator.

[0321] In step S803, the base station sends a second message to the UE.

[0323] The structure of a base station according to an embodiment of the present disclosure will be described later with reference to FIG. 9. FIG. 9 schematically illustrates a schematic structural diagram of a base station (900) according to an embodiment of the present disclosure. The base station (900) can be used to perform the method (800) described with reference to FIG. 8.

[0324] As illustrated in FIG. 9, the base station (900) comprises a processing unit or processor (901) which may be a single unit or a combination of multiple units for performing different steps of the method; and a memory in which computer-executable instructions are stored, which causes the base station (900) to perform the method (800) when executed by the processor (902). For simplification, the specification of the present disclosure will describe only the schematic structure of the base station according to an exemplary embodiment of the present disclosure, and the details described above in the method (800) described with reference to FIG. 8 will be omitted.

[0326] In an exemplary embodiment, when executed by the processor (901), the commands that cause the base station (900) to perform the method (800) cause the base station (900) to perform the following operations.

[0327] The base station (900) transmits configuration information for 2-stage random access transmission to the UE.

[0328] The base station (900) receives from the UE a first message containing a preamble and / or data transmitted to the base station by the UE according to a resource configuration determined based on configuration information.

[0329] The base station (900) transmits a second message to the UE as feedback to the first message.

[0331] As previously mentioned, the second message includes at least one of the following.

[0332] (1) Contention resolution identifier

[0333] (2) Uplink Grant

[0334] (3) Temporary C-RNTI

[0335] (4) Timing advance value

[0336] (5) Display PUCCH resources

[0337] (6) Scheduling information for downlink transmission

[0338] (7) Fallback indicator

[0339] (8) Backoff indicator

[0341] A program executed on a device according to the present invention may be a program that enables a computer to control a central processing unit (CPU) to implement the functions of the embodiments of the present disclosure. The program or information processed by the program may be temporarily stored in volatile memory (such as random access memory (RAM)), a hard disk drive (HDD), non-volatile memory (such as flash memory), or other memory systems.

[0342] A program for realizing the functions of the embodiments of the present invention may be recorded on a computer-readable recording medium. Such functions may be realized by causing a computer system to read and execute the programs recorded on the recording medium. The phrase “computer system” as used in the specification of this disclosure may be a computer system embedded in a device and may include an operating system or hardware (e.g., peripheral devices). “Computer-readable recording medium” may be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a recording medium for short-term dynamic storage programs, or other recording medium readable by a computer.

[0343] Various feature or functional blocks used in the devices of the above embodiments may be implemented or realized by circuits (e.g., monolithic integrated circuits or multi-chip integrated circuits). Circuits designed to perform the functions described in the specification of this disclosure may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), or other programmable logic mechanisms, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general-purpose processor may be a microprocessor or a conventional processor, a controller, a microcontroller, or a state machine. The circuit may be a digital circuit or an analog circuit. Additionally, one or more embodiments of the present invention may be implemented using new integrated circuit technologies in the context of new integrated circuit technologies that replace existing integrated circuits due to advancements in semiconductor technology.

[0344] As described above, embodiments of the present invention have been described in detail with reference to the accompanying drawings. However, specific structures are not limited to the above embodiments, and the present invention includes all design modifications that do not depart from the spirit of the present invention. Furthermore, the present invention may be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included within the scope of the present invention. Additionally, components having the same effect as described in the above embodiments may be substituted for one another.

[0345] The foregoing description is merely a description of preferred embodiments of the present application and the principles of the applied technology. A person skilled in the art should understand that the scope of the present invention is not limited to technical solutions formed by specifically combining the technical features, but should include other technical solutions formed by arbitrarily combining the technical features and their equivalent features, for example, technical solutions formed by replacing the technical features with technical features having similar functions (though not limited to) the present application.

Claims

Claim 1 A method performed by a user equipment (UE) of a wireless communication system, comprising: receiving a reference signal from a base station; determining whether the reference signal received power (RSRP) of the reference signal exceeds a threshold value set for selecting between a 2-step random access (RA) and a 4-step RA; if the RSRP exceeds the set threshold value, setting the RA type to the 2-step RA; if the RSRP does not exceed the set threshold value, setting the RA type to the 4-step RA; and transmitting a first message to the base station that includes an RA preamble according to the RA type, wherein if the RA type is set to the 2-step RA, the method further comprises: determining two radio network temporary identifiers (RNTIs) used to detect a second message related to a random access response (RAR) in response to the first message; and detecting the second message within a RAR window based on one of the two RNTIs. Claim 2 delete Claim 3 delete Claim 4 delete Claim 5 The method of claim 1 further comprises the step of transmitting a message 3 containing a medium access control (MAC) protocol data unit (PDU) to a base station in response to data received based on the second message not containing a contention resolution identity and a random access preamble identifier within the data matching a preamble index transmitted to the base station, wherein the MAC PDU included in the message 3 is identical to the MAC PDU included in the first message transmitted to the base station. Claim 6 The method of claim 1, wherein when the RA type is set to the 2-step RA, the method further comprises: the step of transmitting a PUSCH (physical uplink shared channel) to the base station after transmitting the RA preamble for the 2-step RA; and the step of detecting downlink control information (DCI) within the RAR window, wherein the RAR window starts at the earliest CORESET (control resource set) after at least one symbol from the last symbol of the PUSCH. Claim 7 In paragraph 6, the method wherein the PUSCH uses the same spatial filter as the RA preamble. Claim 8 A method performed by a base station of a wireless communication system comprises: transmitting a reference signal to user equipment (UE); and receiving a first message from the UE that includes an RA preamble according to a random access (RA) type, wherein if the reference signal received power (RSRP) of the reference signal exceeds a set threshold, the RA type is a 2-step RA, and if the RSRP does not exceed the set threshold, the RA type is a 4-step RA, and if the RA type is a 2-step RA, the method further comprises: transmitting a second message associated with a random access response (RAR) to the UE in response to the first message, wherein the second message is transmitted based on one of two radio network temporary identifiers (RNTI) for the second message within a RAR window. Claim 9 delete Claim 10 delete Claim 11 delete Claim 12 In claim 8, the method further comprises the step of receiving a message 3 containing a medium access control (MAC) protocol data unit (PDU) from the UE in response to data transmitted based on the second message not containing a contention resolution identity and a random access preamble identifier within the data matching a preamble index received from the UE, wherein the MAC PDU included in the message 3 is the same as the MAC PDU included in the first message received from the UE. Claim 13 In claim 8, where the RA type is the 2-step RA, the method further comprises: receiving a PUSCH (physical uplink shared channel) from the UE after receiving the RA preamble for the 2-step RA; and transmitting downlink control information (DCI) within the RAR window, wherein the RAR window starts at the earliest CORESET (control resource set) after at least one symbol from the last symbol of the PUSCH. Claim 14 In paragraph 13, the method wherein the above PUSCH uses the same spatial filter as the above RA preamble. Claim 15 In a user equipment (UE) of a wireless communication system, at least one transceiver; and at least one processor communicatively coupled to the at least one transceiver; and includes at least one memory that is communiquently coupled to the at least one processor and stores instructions, wherein the instructions are executed by the at least one processor individually or in any combination, and the UE: receives a reference signal from a base station and determines whether the RSRP (reference signal received power) of the reference signal exceeds a threshold set for selection between 2-step RA (random access) and 4-step RA, if the RSRP exceeds the set threshold, sets the RA type to the 2-step RA, and if the RSRP does not exceed the set threshold, sets the RA type to the 4-step RA, transmits a first message to the base station including an RA preamble according to the RA type, and if the RA type is set to the 2-step RA: two RNTIs (radio network temporary identifiers) used to detect a second message related to a RAR (random access response) in response to the first message A UE that determines and detects the second message within the RAR window based on one of the two RNTIs. Claim 16 In a base station of a wireless communication system, at least one transceiver; and at least one processor communicatively coupled to the at least one transceiver; A base station comprising at least one memory that is communiquently coupled to the at least one processor and stores instructions, wherein the instructions are executed by the at least one processor individually or in any combination, so that the base station transmits a reference signal to a user equipment (UE) and receives a first message from the UE containing an RA preamble according to a random access (RA) type, wherein if the reference signal received power (RSRP) of the reference signal exceeds a set threshold, the RA type is a 2-step RA, if the RSRP does not exceed the set threshold, the RA type is a 4-step RA, and if the RA type is a 2-step RA, the instructions cause the base station to transmit a second message associated with a random access response (RAR) to the UE in response to the first message, wherein the second message is transmitted based on one of two radio network temporary identifiers (RNTI) for the second message within a RAR window.

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