Frequency domain offset parameter determination method, user equipment, and computer readable medium

Abstract

Embodiments of the present disclosure disclose a method for determining a frequency domain offset parameter of a preamble sequence in a random access channel, comprising: obtaining a random access channel subcarrier spacing Δf RA , a preamble sequence length L RA , and an uplink channel subcarrier spacing Δf from a base station; and determining a frequency domain offset parameter of the preamble sequence in the random access channel according to the obtained random access channel subcarrier spacing Δf RA , the preamble sequence length L RA , and the uplink channel subcarrier spacing Δf Embodiments of the present disclosure also disclose a corresponding UE, and a corresponding computer readable medium.

Description

[0001] This application is a divisional application of Chinese invention patent application No. 201810057947.4, filed on January 19, 2018. Technical Field

[0002] This application relates to the field of wireless communication technology, and in particular to a method for determining the frequency domain offset parameter of a preamble sequence in a random access channel, as well as corresponding user equipment and computer-readable medium. Background Technology

[0003] With the rapid development of the information industry, especially the growing demand from mobile internet and the Internet of Things (IoT), unprecedented challenges are being brought to future mobile communication technologies. According to the International Telecommunication Union (ITU) report ITU-R M. [IMT.BEYOND 2020.TRAFFIC], it is projected that by 2020, mobile traffic will increase nearly 1000 times compared to 2010 (the 4G era), and the number of user equipment (UE) connections will exceed 17 billion. With the massive influx of IoT devices into mobile communication networks, the number of connected devices will be even more staggering. To address these unprecedented challenges, the communications industry and academia have launched extensive research into fifth-generation mobile communication technology (5G) for the 2020s. Currently, the ITU report ITU-R M. [IMT.VISION] discusses the framework and overall goals of future 5G, providing detailed explanations of 5G's demand outlook, application scenarios, and key performance indicators. In response to new demands in 5G, the ITU report ITU-R M. [IMT. FUTURE TECHNOLOGY TRENDS] provides information on technology trends related to 5G, aiming to address significant issues such as significantly improved system throughput, consistent user experience, scalability to support IoT, latency, energy efficiency, cost, network flexibility, support for emerging services, and flexible spectrum utilization.

[0004] Random access is a crucial means of UE access. After completing downlink synchronization via downlink synchronization signals, the UE needs to undergo random access to register in the cell, obtain uplink timing advance instructions, and complete uplink synchronization. Random access is classified into contention-based random access and contention-free random access based on whether the UE exclusively possesses preamble sequence resources. In contention-based random access, multiple UEs may select the same preamble sequence from the same preamble sequence resources while attempting to establish an uplink link. Therefore, conflict resolution mechanisms are an important research direction in random access. How to reduce the probability of conflicts and how to quickly resolve conflicts that have already occurred are key indicators affecting the performance of random access.

[0005] In LTE-A, the contention-based random access procedure consists of four steps, such as... Figure 1 As shown. Before the random access procedure begins, the base station sends the configuration information for the random access procedure to the UE, and the UE performs the random access procedure according to the received configuration information.

[0006] In step 1, the UE randomly selects a preamble sequence from the preamble sequence resource pool and sends it to the base station. The base station performs correlation detection on the received signal to identify the preamble sequence sent by the UE.

[0007] In step 2, the base station sends a Random Access Response (RAR) to the UE, which includes a random access preamble sequence identifier, a timing advance instruction determined based on the delay estimate between the UE and the base station, a Temporary Cell-Radio Network Temporary Identifier (TC-RNTI), and time-frequency resources allocated for the UE's next uplink transmission.

[0008] In step 3, the UE sends message 3 (abbreviation: MSg3) to the base station based on the information in the RAR. MSg3 contains information such as the UE identifier and RRC link request. The UE identifier is unique to the UE and is used to resolve conflicts.

[0009] In step 4, the base station sends a conflict resolution identifier to the UE, which includes the UE identifier of the winner in the conflict resolution. After detecting its own identifier, the UE upgrades its temporary cell radio network temporary identifier to a cell radio network temporary identifier (C-RNTI) and sends an acknowledgment (ACK) signal to the base station to complete the random access procedure and wait for the base station's scheduling. Otherwise, the UE will start a new random access procedure after a delay.

[0010] For a contention-free random access procedure, since the base station knows the UE identifier, it can allocate a preamble sequence for the UE. Therefore, when sending the preamble sequence, the UE does not need to randomly select a sequence but will use the allocated preamble sequence. After detecting the allocated preamble sequence, the base station sends a corresponding random access response, including timing advance and uplink resource allocation information. After receiving the random access response, the UE considers uplink synchronization complete and waits for further scheduling by the base station. Therefore, the initial access and contention-free random access procedures only contain two steps: step one is sending the preamble sequence; step two is sending the random access response.

[0011] Regardless of whether random access is contention-based or non-contention-based, the first step in initiating random access is to transmit a preamble sequence on the random access channel. In LTE, the baseband signal generation formula is as follows:

[0012]

[0013] In the above formula, β PRACH N is the amplitude adjustment factor calculated by the power control process. ZC x is the sequence length. u，v (n) is the preamble sequence, K is the factor used to adjust the subcarrier spacing difference between the random access channel and the uplink channel, and Δf RA Let T be the subcarrier spacing of the random access channel, k0 be a parameter used to adjust the frequency domain position of the random access channel, and T be the subcarrier spacing of the random access channel. CP This is the length of the loop prefix. (Parameter) To adjust the frequency domain position of the random access preamble sequence so that its distance from the uplink shared channel at both ends is the same (i.e., the guard interval at both ends of the preamble sequence is the same), the specific values ​​are shown in Table 1.

[0014] Table 1: Parameters The value of

[0015]

[0016] As can be seen, this parameter is directly related to the subcarrier spacing of the random access channel.

[0017] For 5G systems, the subcarrier spacing supported by the system and the random access channel is more diverse. Specifically, the uplink supports subcarrier spacings of 15 / 30 / 60 / 120kHz, while the random access channel supports subcarrier spacings of 1.25 / 5 / 15 / 30 / 60 / 120kHz. This combination of uplink and random access channel subcarrier spacings makes adjusting the preamble sequence position more complex.

[0018] In existing 5G technologies, the subcarrier spacing supported by the uplink and the subcarrier spacing supported by the random access channel are more diverse. A single or a few parameters used to adjust the frequency domain position of the preamble sequence will not be able to satisfy all possible subcarrier spacing combinations. Summary of the Invention

[0019] The technical problem this disclosure aims to solve is that existing schemes for adjusting the parameters of the preamble sequence in the frequency domain cannot meet the requirements of various possible uplink shared channel subcarrier spacings and random access channel subcarrier spacings in 5G. To address this problem, this disclosure proposes a scheme for determining the frequency domain offset parameters of the preamble sequence in the random access channel, applicable to various combinations of subcarrier spacings.

[0020] According to one aspect of this disclosure, a method is provided for determining the frequency domain offset parameter of a preamble sequence in a random access channel, comprising: obtaining the random access channel subcarrier spacing Δf from a base station. RA Leader sequence length L RA and the uplink channel subcarrier spacing Δf; and based on the obtained random access channel subcarrier spacing Δf RA Leader sequence length L RA The frequency offset parameter of the preamble sequence in the random access channel is determined by the uplink channel subcarrier spacing Δf.

[0021] According to another aspect of this disclosure, a UE is provided, comprising:

[0022] Processor; and

[0023] The memory stores computer-executable instructions that, when executed by a processor, cause the processor to perform the following operations: obtain the random access channel subcarrier spacing Δf from the base station. RA Leader sequence length L RA and the uplink channel subcarrier spacing Δf; and based on the obtained random access channel subcarrier spacing Δf RA Leader sequence length L RAThe frequency offset parameter of the preamble sequence in the random access channel is determined by the uplink channel subcarrier spacing Δf.

[0024] In one exemplary embodiment, the frequency domain offset parameter of the preamble sequence in the random access channel is determined. Further, it includes: calculating the frequency domain offset parameter of the preamble sequence in the random access channel according to the following formula.

[0025]

[0026] Where, N u This indicates the number of subcarriers used as guard bands within the random access channel, and the symbol [·] indicates the rounding operation.

[0027] In one exemplary embodiment, the frequency domain offset parameter of the preamble sequence in the random access channel is determined. Further, it includes: calculating the frequency domain offset parameter of the preamble sequence in the random access channel according to the following formula.

[0028]

[0029] Where, N u This indicates the number of subcarriers used as guard bands within the random access channel, and the symbol [·] indicates the rounding operation.

[0030] In one exemplary embodiment, the frequency domain offset parameter of the preamble sequence in the random access channel is determined. Further, it includes: calculating the frequency domain offset parameter of the preamble sequence in the random access channel according to the following formula.

[0031]

[0032] Where, N u This indicates the number of subcarriers used as guard bands within the random access channel, and the symbol [·] indicates the rounding operation.

[0033] In one exemplary embodiment, in The number of random access channel physical resource blocks per uplink channel subcarrier spacing Δf symbol This is the floor operation, where N is N. SC The number of subcarriers in a physical resource block.

[0034] In one exemplary embodiment, N is obtained according to the following correspondence table. u :

[0035]

[0036]

[0037] In one exemplary embodiment, the frequency domain offset parameter of the preamble sequence in the random access channel is determined. Further, this includes determining the frequency domain offset parameter of the preamble sequence in the random access channel according to one of the following correspondence tables.

[0038]

[0039]

[0040]

[0041]

[0042] According to another aspect of this disclosure, a computer-readable medium is provided having instructions stored thereon that, when executed by a processor, cause the processor to perform the method as described above. Attached Figure Description

[0043] Figure 1 A schematic diagram of a traditional contention-based random access procedure is shown.

[0044] Figure 2 A flowchart illustrating a method for determining the frequency domain offset parameter of a preamble sequence in a random access channel, performed on the UE side according to an exemplary embodiment of the present disclosure, is shown schematically.

[0045] Figure 3 A schematic diagram of the random access channel guard band is shown.

[0046] Figure 4 A schematic diagram of another random access channel guard band is shown.

[0047] Figure 5 A schematic diagram of the structure of a UE according to an exemplary embodiment of the present disclosure is shown.

[0048] Figure 6 This is a DFT-based baseband signal generation method;

[0049] Figure 7 An improved method for generating baseband signals for the preamble sequence;

[0050] Figure 8 This is another way to generate baseband signals. Detailed Implementation

[0051] The embodiments of this disclosure are described in detail below, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this disclosure, and should not be construed as limiting this disclosure.

[0052] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in this disclosure means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that when we say an element is “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Furthermore, “connected” or “coupled” as used herein can include wireless connections or wireless coupling. The term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.

[0053] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.

[0054] Those skilled in the art will understand that, as used herein, "UE" and "terminal" include both devices that are wireless signal receivers, devices that are wireless signal receivers without transmitting capability, and devices with receiving and transmitting hardware, devices that have receiving and transmitting hardware capable of bidirectional communication over a bidirectional communication link. Such devices may include: cellular or other communication devices having a single-line display, a multi-line display, or a cellular or other communication device without a multi-line display; PCS (Personal Communication Services) that can combine voice, data processing, fax, and / or data communication capabilities; PDA (Personal Digital Assistant) that may include a radio frequency receiver, pager, Internet / intranet access, web browser, notepad, calendar, and / or GPS (Global Positioning System) receiver; and conventional laptop and / or handheld computers or other devices that have and / or include a radio frequency receiver. As used herein, "UE" or "terminal" can be portable, transportable, installed in a means of transportation (air, sea, and / or land), or suitable and / or configured to operate locally and / or in a distributed manner, operating in any other location on Earth and / or in space. "UE" or "terminal" as used herein can also be a communication terminal, an internet access terminal, or a music / video playback terminal, such as a PDA, a MID (Mobile Internet Device), and / or a mobile phone with music / video playback capabilities, or a smart TV, set-top box, etc. Furthermore, "UE" or "terminal" can be used interchangeably with "user" or "user equipment."

[0055] To address the issue that existing technologies for adjusting the preamble sequence's frequency domain position cannot satisfy the various possible uplink shared channel subcarrier spacings and random access channel subcarrier spacings in 5G, embodiments of this disclosure propose a method for generating baseband signals executed at the UE, comprising the following steps:

[0056] Read random access configuration information from the base station, including random access channel configuration information and preamble sequence configuration information, etc.

[0057] The random access channel subcarrier spacing is obtained from the random access channel configuration information, and the preamble sequence length information is obtained from the preamble sequence configuration information; and the uplink channel subcarrier spacing is obtained from other system information (such as Remaining Minimum System Information, RMSI) sent by the base station.

[0058] Based on the obtained random access channel subcarrier spacing, uplink channel subcarrier spacing, and preamble sequence length, determine the frequency domain offset parameter of the preamble sequence in the random access channel; and

[0059] The baseband signal is generated based on the frequency domain offset parameter of the determined preamble sequence in the random access channel.

[0060] Specifically, the baseband signal is generated according to formula (1):

[0061]

[0062] K = Δf / Δf RA (1)

[0063] Wherein, parameter L RA Δf is the preamble sequence length, k0 is a parameter for adjusting the position of the random access channel, and Δf is the uplink data channel or the subcarrier spacing of the initial access uplink channel. RA For the random access channel subcarrier spacing, T is the length of the cyclic prefix of the leading sequence. c The sampling interval is... This is a parameter used to adjust the position of the preamble sequence in the random access channel, specifically the frequency domain offset parameter of the preamble sequence in the random access channel in this paper.

[0064] Therefore, the focus of this disclosure is on the frequency domain offset parameter of the preamble sequence in the random access channel. The determination.

[0065] The following will refer to Figure 2 The flowchart of a method for determining the frequency domain offset parameter of a preamble sequence in a random access channel, performed at a UE according to an exemplary embodiment of the present disclosure, is described in detail.

[0066] Figure 2 A flowchart illustrating a method 200 performed at a UE to determine a frequency domain offset parameter of a preamble sequence in a random access channel, according to an exemplary embodiment of this disclosure, is shown schematically. Figure 2 As shown, method 200 may include steps 201 and 202.

[0067] In step 201, the UE can obtain the random access channel subcarrier spacing Δf from the base station. RA Leader sequence length L RA And the uplink channel subcarrier spacing Δf.

[0068] In step 202, the UE can determine the random access channel subcarrier spacing Δf based on the obtained information. RALeader sequence length L RA The frequency offset parameter of the preamble sequence in the random access channel is determined by the uplink channel subcarrier spacing Δf.

[0069] Frequency offset parameter of the preamble sequence in the random access channel The subcarrier spacing Δf of the random access channel can be obtained through calculation or by looking up a predefined random access channel. RA Leader sequence length L RA and the frequency domain offset parameter of the uplink channel subcarrier spacing Δf and the preamble sequence in the random access channel The correspondence table is obtained.

[0070] In this article, unless otherwise specified, "uplink channel" refers to the uplink data channel, such as the Physical Uplink Shared Channel (PUSCH).

[0071] The frequency domain offset parameter of the preamble sequence in the random access channel is obtained through calculation. In one embodiment, the random access channel subcarrier spacing Δf obtained from the base station can be used as a reference. RA Leader sequence length L RA Given the uplink channel subcarrier spacing Δf, calculate the frequency domain offset parameter of the preamble sequence in the random access channel. The embodiments disclosed herein provide the following implementation methods.

[0072] Implementation Method 1

[0073] In this embodiment, the frequency domain offset parameter of the preamble sequence in the random access channel is calculated. When determining the value of , it is necessary to ensure that the protection bandwidth between the subcarriers of the closest transmitted data at both ends of the preamble sequence is consistent.

[0074] like Figure 3 As shown, by setting parameter Kk0, the first subcarrier of the random access channel overlaps with the subcarrier of the uplink channel. Therefore, the distance between the first subcarrier of the random access channel and the last subcarrier of the adjacent uplink channel is the subcarrier interval of one uplink channel.

[0075] As can be seen, when calculating the guard band of the first subcarrier of the preamble sequence relative to the adjacent uplink channel, in addition to calculating the guard band within the random access channel, it is also necessary to calculate the subcarrier width of one uplink channel. However, when calculating the guard band of the last subcarrier of the preamble sequence relative to the adjacent uplink channel, it is necessary to calculate the subcarrier spacing of one random access channel.

[0076] Specifically, assuming the uplink channel subcarrier spacing and the random access channel subcarrier spacing Δf RAand the length L of the leader sequence RA The calculation yields the number of subcarriers used as guard bands within the random access channel, denoted as N. u Therefore, when calculating the bandwidth distance between the subcarriers at both ends of the preamble sequence and the adjacent uplink channel subcarriers, this bandwidth BW g For (N) u +1)Δf RA +Δf, where N u +1 considers the subcarriers used as guard bands within the random access channel, as well as the subcarrier spacing between the last subcarrier of the random access channel and the adjacent uplink channel; this subcarrier spacing is the subcarrier spacing of the random access channel. Δf is the uplink channel subcarrier spacing, used to calculate the guard band bandwidth when calculating the distance between the first subcarrier of the preamble sequence and the adjacent uplink channel subcarrier. This represents the number of random access channel subcarriers within the guard band of the first subcarrier of the first preamble sequence, relative to the last subcarrier of the adjacent uplink channel. This parameter can be calculated as follows:

[0077] First, the bandwidth of the data subcarriers at both ends of the random access preamble sequence is calculated as follows:

[0078] BW g =(N u +1)Δf RA +Δf

[0079] The bandwidth of one side of the guard band can then be obtained:

[0080] BW h =BW g / 2

[0081] Based on the uplink channel subcarrier width, the number of subcarriers in the aforementioned random access channel can be obtained as follows:

[0082]

[0083] The symbol [·] represents the rounding operation, which can be replaced by the rounding up or rounding down symbols.

[0084] In summary, parameters It can be calculated using the following formula:

[0085]

[0086] The symbol [·] represents the rounding operation, which can be replaced by the rounding up or rounding down symbols.

[0087] Implementation Method 2

[0088] In this embodiment, when calculating the subcarrier spacing within the random access channel, the distance between the last subcarrier in the random access channel and the adjacent uplink channel is not calculated. That is, when calculating the guard band between the last subcarrier of the preamble sequence and the subcarrier of the adjacent uplink channel, only the number of subcarriers within the random access channel is calculated. At this time, the parameters... The calculation is as follows.

[0089] First, the bandwidth of the data subcarriers at both ends of the random access preamble sequence is calculated as follows:

[0090] BW g =N u Δf RA +Δf

[0091] The bandwidth of one side of the guard band can then be obtained:

[0092] BW h =BW g / 2

[0093] Based on the uplink channel subcarrier width, the number of subcarriers in the aforementioned random access channel can be obtained as follows:

[0094]

[0095] The symbol [·] represents the floor operation. This floor operation can be replaced by the floor up or floor down symbols.

[0096] In summary, parameters It can be calculated using the following formula:

[0097]

[0098] The symbol [·] represents the floor operation. This floor operation can be replaced by the floor up or floor down symbols.

[0099] Implementation Method 3

[0100] In this implementation, only the number of subcarriers within the random access channel is considered, ensuring that the number of subcarriers on both sides of the random access preamble sequence is approximately equal, such as... Figure 4 As shown.

[0101] At this point, the number of subcarriers used for guarding the frequency band before the first subcarrier in the preamble sequence... The following can be calculated:

[0102]

[0103] The symbol [·] represents the floor operation. This floor operation can be replaced by the floor up or floor down symbols.

[0104] Although this disclosure only provides the above three embodiments as parameters for calculating the frequency domain offset of the preamble sequence in a random access channel. The exemplary implementation is described herein, but this disclosure is not limited thereto; other methods for adjusting the random access channel subcarrier spacing Δf are also described. RA Leader sequence length L RA The frequency domain offset parameter of the preamble sequence in the random access channel is calculated using the uplink channel subcarrier spacing Δf. Any suitable method also falls within the scope of this disclosure.

[0105] In the above calculation process, N u The number of subcarriers used for guard band protection within the random access channel can be determined by looking up the predefined random access channel subcarrier spacing Δf. RA Leader sequence length L RA and uplink channel subcarrier spacing Δf and N u The correspondence is obtained from the table (Table 2 below), or based on the random access channel subcarrier spacing Δf. RA Leader sequence length L RA It is calculated from the uplink channel subcarrier spacing Δf.

[0106] Table 2: Number of Guard Subcarriers

[0107]

[0108]

[0109] N is obtained through calculation u In this embodiment, the number of random access channel physical resource blocks per uplink channel subcarrier interval is first calculated:

[0110]

[0111] Where, N SC This represents the number of subcarriers in a physical resource block, and its value can be fixed at 12. The number of random access channel physical resource blocks per uplink channel subcarrier interval; symbol This is a rounding operation.

[0112] The number of subcarriers used to guard the frequency band in the random access channel is then calculated as follows:

[0113]

[0114] By finding the predefined random access channel subcarrier interval Δf RA Leader sequence length L RA and the frequency domain offset parameter of the uplink channel subcarrier spacing Δf and the preamble sequence in the random access channel The frequency offset parameter of the preamble sequence in the random access channel is obtained from the correspondence table. In the embodiments, the present disclosure provides the following possible correspondence tables.

[0115] One possible correspondence table is shown in Table 3.

[0116] Table 3: Parameters One possible value

[0117]

[0118]

[0119] Another possible correspondence table is shown in Table 4.

[0120] Table 4: Parameters Another possible value

[0121]

[0122] The third possible correspondence is shown in Table 5.

[0123] Table 5: Parameters Another possible value

[0124]

[0125]

[0126] In the examples shown in Tables 3, 4, and 5 above, both the UE and the base station are aware of the predefined correspondence table, and obtain the random access channel subcarrier spacing Δf from the base station. RA Leader sequence length L RA The uplink channel subcarrier spacing Δf in the system information can be obtained from the corresponding relationship table.

[0127] Alternatively, Table 5 can be simplified based on the format or length of the leader sequence, as follows:

[0128] If the sequence length L RA If it is 139, then The value is 3;

[0129] If the sequence length L RA If the value is 839, and the uplink channel subcarrier spacing is not 60kHz, then The value is 13;

[0130] If the sequence length L RAThe value is 839, and the uplink channel subcarrier spacing is 60kHz. The value is 157.

[0131] Furthermore, since the subcarrier spacing and sequence length of the random access channel are directly determined by the preamble sequence format, the frequency domain position offset can be determined based on the preamble sequence format and the uplink channel subcarrier spacing.

[0132] Taking Table 5 as an example:

[0133] For preamble sequence formats 0, 1, and 2, if the uplink channel subcarrier spacing is not 60kHz, the frequency domain offset is 13; if the uplink channel subcarrier spacing is 60kHz, the offset is 157.

[0134] For preamble sequence format 3, the frequency domain offset is 13.

[0135] For the preamble sequence format A0, A1, A2, A3, B1, B2, B3, C0, C2, A1 / B1, the frequency offset is 3. The above description can also be determined by looking up a table.

[0136] For other correspondence tables (such as Tables 3 and 4), optimization can be performed in a similar manner. This involves merging the first two columns of the indexes in Tables 3, 4, and 5 to create a leading sequence format. Possible approaches are shown in Tables 6, 7, and 8.

[0137] Table 6: Parameters Possible ways to determine

[0138]

[0139] Table 7: Parameters Another way to determine

[0140]

[0141]

[0142] Table 8: Parameters Another way to obtain a value

[0143]

[0144] The following will refer to Figure 5 The structure of the UE according to an exemplary embodiment of the present invention will be described. Figure 5 A structural block diagram of a UE 500 according to an exemplary embodiment of the present invention is schematically shown. The UE 500 can be used to perform reference... Figure 2Method 200 is described. For simplicity, only an illustrative structure of the UE according to exemplary embodiments of this disclosure is described herein, and references to previously cited examples are omitted. Figure 2 The details of the method described have already been elaborated in 200.

[0145] like Figure 5 As shown, UE 500 includes a processing unit or processor 501, which may be a single unit or a combination of multiple units for executing different steps of the method; and a memory 502 storing computer-executable instructions that, when executed by processor 501, cause processor 501 to perform the following operations: obtaining the random access channel subcarrier spacing Δf from the base station. RA Leader sequence length L RA and the uplink channel subcarrier spacing Δf; and based on the obtained random access channel subcarrier spacing Δf RA Leader sequence length L RA The frequency offset parameter of the preamble sequence in the random access channel is determined by the uplink channel subcarrier spacing Δf.

[0146] As mentioned earlier, the frequency domain offset parameter of the preamble sequence in the random access channel It can be calculated using, for example, the three methods described above, or it can be obtained by looking up a predefined random access channel subcarrier spacing Δf. RA Leader sequence length L RA and the frequency domain offset parameter of the uplink channel subcarrier spacing Δf and the preamble sequence in the random access channel The corresponding relationship table (for example, one of Tables 3 to 8 mentioned above) is obtained, and for details, please refer to the table for... Figure 2 The relevant description of method 200.

[0147] The following describes a method for generating a random access preamble baseband signal. As described in the previous embodiments, the random access baseband signal is generated using the following formula.

[0148]

[0149] K = Δf / Δf RA

[0150] in, The frequency domain sequence generated for the preamble sequence is produced using the following formula.

[0151]

[0152] k = 0, 1, ..., L RA -1

[0153] β PRACHThe amplitude adjustment factor, obtained for power control, is used to ensure that the transmitted signal meets the power control constraints. u，v (k) is the frequency domain signal obtained by transforming the preamble sequence into the frequency domain, which is obtained using the following formula.

[0154]

[0155] Where, x u，c (m) is the time-domain leader sequence.

[0156] As can be seen from the above description, the following steps are required to generate the baseband signal: DFT (Discrete Fourier Transform), used to obtain the signal from the time-series preamble sequence x. u，v (m) Generate frequency domain sequence y u，v (n); Subcarrier mapping, used to select the frequency domain position of the preamble sequence based on its frequency domain position in the random access channel and its position within the random access channel; IDFT (Inverse Discrete Fourier Transform), used to generate the final time-domain baseband signal. The above steps can be used... Figure 6 express.

[0157] For some leading sequence formats, repetition is required in the time domain. Figure 6 The repeat module in the code is used to generate repeating leader sequence symbols.

[0158] In practice, DFT and IDFT are typically implemented using FFT (Fast Fourier Transform) and IFFT (Inverse Fast Fourier Transform), respectively, with the FFT point count being a power of 2. If the above generation method is used, the mismatch between the subcarrier spacing of the random access channel and the uplink data channel will lead to some implementation problems.

[0159] Specifically, when the uplink channel subcarrier spacing is greater than the random access subcarrier spacing, the IFFT used when converting the frequency domain signal to the time domain signal will require a larger number of IFFT points. A simple example is when the random access channel subcarrier spacing is 1.25kHz and the uplink channel is 15kHz. To meet the sampling interval specified in the protocol, a 49,152-point IFFT is required. Even for the sampling interval in LTE, a 24,576-point IFFT is required.

[0160] However, if the uplink channel subcarrier spacing is smaller than the random access subcarrier spacing, directly using the uplink channel subcarrier spacing will result in some waste.

[0161] One possible improvement is to use an IFFT with a number of points determined based on the length of the random access preamble sequence, and to determine the sampling interval for time-domain sampling based on the number of IFFT points and the subcarrier spacing of the random access channel. The sampling rate is then adjusted after adding a cyclic prefix.

[0162] The flowchart of this improved method is as follows: Figure 7 As shown.

[0163] Figure 7 In this context, the number of points in the IDFT is selected based on the sequence length. For example, for a leading sequence of length 839, a 1024-point IDFT is selected; for a leading sequence of length 139, a 512-point IDFT is selected.

[0164] The sampling interval in the time domain is selected based on the number of IDFT points and the frequency of the random access channel subcarriers, as shown in the table below:

[0165] Table 9: Selection of Time Domain Sampling Frequency

[0166]

[0167]

[0168] The length of the subsequently added cyclic prefix should also be adjusted based on the relationship between the required sampling frequency domain and the final sampling frequency. The sampling frequency of the time-domain signal generated after IDFT is f. RA The sampling interval is T RA =1 / f RA The length of the added loop prefix is ​​. in, The number of cyclic prefix points calculated based on the IDFT points can be predetermined according to the preamble sequence format.

[0169] Considering that none of the possible time-domain sampling intervals exceed the maximum sampling frequency specified by 5G, subsequent sampling interval adjustments can be made by upsampling. The time-domain signal after IDFT, possible time-domain repetition, and the addition of a cyclic prefix will be upsampled to generate a time-domain signal whose sampling rate meets the requirements of the 5G system.

[0170] Since the aforementioned process does not include frequency domain location selection (in... Figure 6 As shown in the flowchart, subcarrier selection is used (this is done), therefore the frequency domain position of the generated time-domain signal needs to be adjusted. Considering that the frequency domain position is reflected in the time domain as phase adjustment, this module performs phase adjustment on the generated time-domain signal.

[0171] A concrete example is if the first subcarrier of the preamble sequence needs to be offset by a position φ in the frequency domain. k Then the phase adjustment required for the signal at time t is: If the effect of CP is taken into account, the phase adjustment amount should be: Where T cLet be the system sampling rate. It should be noted that the frequency domain offset in this example is measured using the subcarrier spacing Δf of the uplink channel. If the subcarrier spacing of the random access channel is used, the formula needs to be modified, and the phase adjustment at time point t is: If the effect of CP is taken into account, the phase adjustment amount is: Where K = Δf / Δf RA .

[0172] In the previous example, the preamble sequence is defined in the time domain, so a DFT is first performed to transform it into a frequency domain signal. Another simpler approach is to directly use a sequence of length L. RA The frequency domain sequence, that is, directly using the sequence y u，c (k), or sequence At this point, the flowchart for generating the preamble sequence baseband signal is as follows: Figure 8 As shown.

[0173] Computer-executable instructions or programs for implementing the functions of the various embodiments of the present invention can be recorded on a computer-readable storage medium. The corresponding functions can be implemented by causing a computer system to read and execute the programs recorded on the recording medium. The term "computer system" here can refer to a computer system embedded in the device, and may include an operating system or hardware (such as peripheral devices). "Computer-readable storage medium" can be a semiconductor recording medium, an optical recording medium, a magnetic recording medium, a short-time dynamic program storage medium, or any other computer-readable recording medium.

[0174] Various features or functional modules of the devices used in the above embodiments can be implemented or executed by circuits (e.g., monolithic or multi-chip integrated circuits). Circuits designed to perform the functions described in this specification may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or any combination of the above devices. A general-purpose processor may be a microprocessor, or any existing processor, controller, microcontroller, or state machine. The above circuits may be digital circuits or analog circuits. In cases where advancements in semiconductor technology have led to new integrated circuit technologies that replace existing integrated circuits, one or more embodiments of the present invention may also be implemented using these new integrated circuit technologies.

[0175] Those skilled in the art will understand that this disclosure includes devices for performing one or more of the operations described in this application. These devices may be specifically designed and manufactured for the desired purpose, or may include known devices found in general-purpose computers. These devices have computer programs stored therein that can be selectively activated or reconfigured. Such computer programs may be stored in a device (e.g., a computer)-readable medium or in any type of medium suitable for storing electronic instructions and coupled to a bus, including but not limited to any type of disk (including floppy disks, hard disks, optical disks, CD-ROMs, and magneto-optical disks), ROM (Read-Only Memory), RAM (Random Access Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), flash memory, magnetic cards, or optical cards. That is, a readable medium includes any medium by which a device (e.g., a computer) stores or transmits information in a readable form.

[0176] Those skilled in the art will understand that each block in these structural diagrams and / or block diagrams and / or flow diagrams, as well as combinations of blocks in these structural diagrams and / or block diagrams and / or flow diagrams, can be implemented using computer program instructions. Those skilled in the art will understand that these computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing method for implementation, thereby enabling the processor of the computer or other programmable data processing method to execute the schemes specified in the blocks or plurality of blocks of the structural diagrams and / or block diagrams and / or flow diagrams disclosed herein.

[0177] Those skilled in the art will understand that the steps, measures, and schemes in the various operations, methods, and processes discussed in this disclosure can be alternated, modified, combined, or deleted. Furthermore, other steps, measures, and schemes in the various operations, methods, and processes discussed in this disclosure can also be alternated, modified, rearranged, decomposed, combined, or deleted. Furthermore, steps, measures, and schemes in the prior art that are similar to those in the various operations, methods, and processes disclosed in this disclosure can also be alternated, modified, rearranged, decomposed, combined, or deleted.

[0178] The above description is only a partial embodiment of this disclosure. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principles of this disclosure, and these improvements and modifications should also be considered within the scope of protection of this disclosure.

Claims

1. A method performed by a terminal in a wireless communication system, comprising: Receive from the base station first information relating to the length of the random access preamble and second information relating to the first subcarrier spacing of the random access channel; Receive third information from the base station relating to the second subcarrier spacing of the Physical Uplink Shared Channel (PUSCH); Based on a predefined table including the length of the random access preamble, the first subcarrier spacing of the random access channel, the second subcarrier spacing of the PUSCH, and combinations of various offset parameters, the offset parameters corresponding to the first information, the second information, and the third information are determined. Based on the offset parameters corresponding to the first information, the second information, and the third information, a baseband signal for a random access channel is generated; Based on the baseband signal, a random access preamble is sent. The predefined table includes the following combinations: The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 15kHz, and an offset parameter that is a combination of 7 random access channel subcarriers. The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 30kHz, and an offset parameter that is a combination of one random access channel subcarrier. The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 60kHz, and an offset parameter that is a combination of 133 random access channel subcarriers. The random access preamble has a length of 839, a first subcarrier spacing of 5kHz, a second subcarrier spacing of 30kHz, and an offset parameter that is a combination of 10 random access channel subcarriers; and The random access preamble has a length of 839, a first subcarrier spacing of 5kHz, a second subcarrier spacing of 60kHz, and an offset parameter that is a combination of 7 random access channel subcarriers.

2. The method according to claim 1 further includes determining the number of resource blocks of the random access channel based on a combination of the first information, the second information, and the third information.

3. The method according to claim 2, wherein, Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 15kHz, the number of resource blocks is 6; Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 30Hz, the number of resource blocks is 3; Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 60kHz, the number of resource blocks is 2; Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 15kHz, the number of resource blocks is 24. Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 30kHz, the number of resource blocks is 12; and Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 60kHz, the number of resource blocks is 6.

4. The method according to claim 1, characterized in that, When determining the offset parameter, the number of guard subcarriers from both ends of the random access preamble sequence to the nearest PUSCH subcarrier interval is consistent.

5. A method performed by a base station in a wireless communication system, comprising: Send to the terminal first information related to the length of the random access preamble and second information related to the first subcarrier spacing of the random access channel; Send third information to the terminal related to the second subcarrier spacing of the Physical Uplink Shared Channel (PUSCH); Based on the baseband signal of the random access channel, a random access preamble is received. The baseband signal is generated based on offset parameters, which are determined based on a predefined table. The predefined table includes the length of the random access preamble, the first subcarrier spacing of the random access channel, the second subcarrier spacing of the PUSCH, and combinations of the offset parameters. The predefined table includes the following combinations: The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 15kHz, and an offset parameter that is a combination of 7 random access channel subcarriers. The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 30kHz, and an offset parameter that is a combination of one random access channel subcarrier. The random access preamble has a length of 839, a first subcarrier spacing of 1.25kHz, a second subcarrier spacing of 60kHz, and an offset parameter that is a combination of 133 random access channel subcarriers. The random access preamble has a length of 839, a first subcarrier spacing of 5kHz, a second subcarrier spacing of 30kHz, and an offset parameter that is a combination of 10 random access channel subcarriers; and The random access preamble has a length of 839, a first subcarrier spacing of 5kHz, a second subcarrier spacing of 60kHz, and an offset parameter that is a combination of 7 random access channel subcarriers.

6. The method according to claim 5, wherein, The combination of the first information, the second information, and the third information is used to determine the number of resource blocks for the random access channel.

7. The method based on claim 6, wherein, Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 15kHz, the number of resource blocks is 6; Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 30kHz, the number of resource blocks is 3; Based on the random access preamble length of 839, the first subcarrier spacing of 1.25kHz, and the second subcarrier spacing of 60kHz, the number of resource blocks is 2; Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 15kHz, the number of resource blocks is 24. Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 30kHz, the number of resource blocks is 12; and Based on the random access preamble length of 839, the first subcarrier spacing of 5kHz, and the second subcarrier spacing of 60kHz, the number of resource blocks is 6.

8. A terminal in a wireless communication system, comprising: processor; as well as A memory storing computer-executable instructions that, when executed by a processor, cause the processor to perform the method described in any one of claims 1-4.

9. A base station in a wireless communication system, comprising: processor; as well as A memory storing computer-executable instructions that, when executed by a processor, cause the processor to perform the method described in any one of claims 5-7.

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