Communication method and device

Abstract

A communication method and device, which are applied in the technical field of communications, can be applied to a wireless local area network system supporting 802.11 series protocols such as a next-generation WiFi protocol of IEEE 802.11ax, i.e., 802.11be, WiFi 7 or EHT, and the next generation of 802.11be, i.e., WiFi 8, UHR, WiFi AI, or millimeter wave (MMW), and can also be applied to a WPAN system, a sensing system or the like supporting UWB. A first communication device generates a PPDU and sends the PPDU. A second communication device receives the PPDU and performs channel estimation on the basis of an LTF sequence. The PPDU comprises an LTF carrying an LTF sequence, the LTF sequence corresponds to the bandwidth of the PPDU, and the LTF sequence is determined on the basis of a basic LTF sequence and is a 2x mode sequence. The LTF sequence can effectively reduce an error in channel estimation.

Description

Communication method and device

[0001] This application claims priority to the Chinese patent application with application number 202310810353.7 filed with the State Intellectual Property Office of China on June 30, 2023, and priority to the Chinese patent application with the invention name “Communication Method and Device”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0003] In recent years, wireless traffic has grown at an extremely high rate, and users have increasingly demanded higher quality of communication services, such as low latency and ultra-reliability. As a key technology for carrying wireless traffic, wireless local area networks (WLANs) continue to develop and evolve to meet users' increasingly demanding requirements for wireless transmission. To improve the throughput of next-generation wireless LAN systems, a major challenge at the physical layer is how to accurately estimate the channel. For example, the long training field (LTF) in the physical layer (PHY) protocol data unit (PPDU) provides a means for receivers to estimate the multiple-input, multiple-output (MIMO) channel in WLAN systems.

[0004] Different LTFs may use different LTF sequences, that is, LTF is determined based on the LTF sequence. Currently, the maximum bandwidth supported by the Institute of Electrical and Electronics Engineers (IEEE) 802.be standard is 320 MHz, that is, the maximum bandwidth supported by the LTF sequence is 320 MHz.

[0005] Therefore, how to design LTF sequences for next generation WLAN systems is an important task.

[0006] Summary of the Invention

[0007] An embodiment of the present application provides a communication method and apparatus, which provides an LTF sequence when the bandwidth of the PPDU is greater than 320 MHz. The LTF sequence can effectively reduce the peak-to-average power ratio (PAPR) of the LTF signal in a large bandwidth scenario, thereby effectively reducing the error of the channel estimation.

[0008] In a first aspect, an embodiment of the present application provides a communication method, which can be applied to a first communication device, which can be a Wi-Fi device or a Wi-Fi chip or module. The method includes:

[0009] Generate a physical layer protocol data unit (PPDU), the PPDU including a long training field (LTF) carrying an LTF sequence, the length of the LTF sequence corresponding to the bandwidth of the PPDU, the LTF sequence being determined based on a basic LTF sequence corresponding to a basic subchannel, the bandwidth of the PPDU being greater than 320 MHz, and the LTF sequence being a 2x mode sequence; and send the PPDU.

[0010] The LTF sequence provided in the embodiment of the present application can effectively reduce the PAPR of the LTF signal in a large bandwidth scenario, thereby effectively reducing the error in signal estimation.

[0011] In a second aspect, an embodiment of the present application provides a communication method, which can be applied to a second communication device, which can be a Wi-Fi device or a Wi-Fi chip or module. The method includes:

[0012] A physical layer protocol data unit (PPDU) is received, where the PPDU includes a long training field (LTF) carrying an LTF sequence, where the length of the LTF sequence corresponds to the bandwidth of the PPDU, the LTF sequence is determined based on a basic LTF sequence corresponding to a basic subchannel, and the bandwidth of the PPDU is greater than 320 MHz; the LTF sequence is a 2x mode sequence; and channel estimation is performed based on the LTF sequence.

[0013] In combination with the first aspect or the second aspect, in a possible implementation manner, the LTF sequence is determined based on a sequence corresponding to the unit subchannel, and the sequence corresponding to the unit subchannel is determined based on the basic LTF sequence.

[0014] In combination with the first aspect or the second aspect, in a possible implementation manner, the modulus value of the rotation factor of the sequence corresponding to the unit subchannel is 1, and the bandwidth of the unit subchannel is any one of the following: 20 MHz, 40 MHz.

[0015] In combination with the first aspect or the second aspect, in a possible implementation manner, the LTF sequence is determined based on a sequence corresponding to the unit subchannel and a rotation factor sequence, where the rotation factor sequence is a sequence composed of rotation factors.

[0016] In combination with the first aspect or the second aspect, in a possible implementation manner, the modulus value of the rotation factor of the sequence corresponding to the unit subchannel is 1, including: the rotation factor of the sequence corresponding to the unit subchannel is 1 or -1.

[0017] In combination with the first aspect or the second aspect, in one possible implementation, the LTF sequence is obtained based on the periodic extension and phase flipping of the sequence corresponding to the unit subchannel in the frequency domain; wherein the number of periodic extensions is equal to the length of the rotation factor sequence, 1 in the rotation factor sequence corresponds to no phase flipping of the sequence corresponding to the unit subchannel, and -1 in the rotation factor sequence corresponds to phase flipping of the sequence corresponding to the unit subchannel.

[0018] In combination with the first aspect or the second aspect, in a possible implementation manner, the length of the rotation factor sequence is determined by the bandwidth of the PPDU and the bandwidth of the unit subchannel.

[0019] In combination with the first aspect or the second aspect, in one possible implementation, the rotation factor sequence satisfies at least one of the following:

[0020] The values ​​of the first group of elements in the rotation factor sequence are the same as the values ​​of the second group of elements, the second group of elements are elements symmetrical to the first group of elements with the center position of the rotation factor sequence as the symmetry axis, the first group of elements includes the (2*i-1)th element and the (2*i)th element, where i is less than or equal to 1 / 2 times the length of the rotation factor sequence;

[0021] The values ​​of the third group of elements in the rotation factor sequence are opposite to the values ​​of the fourth group of elements. The third group of elements is symmetrical with the center position of the rotation factor sequence as the axis of symmetry, and the positions of the third group of elements are symmetrical with the positions of the fourth group of elements. The third group of elements includes the (2*j-1)th element and the (2*j)th element, where j is less than or equal to 1 / 2 times the length of the rotation factor sequence, and i is not equal to j.

[0022] In combination with the first aspect or the second aspect, in a possible implementation, the bandwidth of the PPDU is 640 MHz, and the LTF sequence includes any one of the following:

[0023] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0024] -LTF 80MHz_2x(1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0025] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0026] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0027] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0028] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0029] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0030] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0031] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0032] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0033] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0034] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0035] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0036] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0037] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x(757:1001),0 23 ,

[0038] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0039] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0040] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0041] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0042] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0043] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0044] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x(502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0045] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0046] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0047] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0048] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0049] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0050] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0051] LTF 80MHz_2x (1:245),LTF 80MHz_2x(246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0052] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0053] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0054] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0055] Among them, LTF 80MHz_2x (1:245) indicates the sequence LTF 80MHz_2x The first to the 245th element in LTF 80MHz_2x (246:500) represents the sequence LTF 80MHz_2x The 246th to 500th elements in LTF 80MHz_2x (502:756) represents the sequence LTF 80MHz_2x The 502nd to 756th elements in LTF 80MHz_2x (757:1001) represents the sequence LTF 80MHz_2x From the 757th element to the 1001th element, the sequence LTF 80MHz_2x is the basic LTF sequence of the 2x mode, 0 23 Indicates that 23 consecutive elements in the LTF sequence are 0.

[0056] In combination with the first aspect or the second aspect, in a possible implementation, the bandwidth of the PPDU is 480 MHz, and the LTF sequence includes any one of the following:

[0057] ±{LTF 80MHz_2x(1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0058] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0059] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0060] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0061] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0062] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0063] ±{-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0064] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0065] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0066] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0067] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0068] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0069] Among them, LTF 80MHz_2x (1:245) indicates the sequence LTF 80MHz_2x The first to the 245th element in LTF 80MHz_2x (246:500) represents the sequence LTF 80MHz_2x The 246th to 500th elements in LTF 80MHz_2x (502:756) represents the sequence LTF 80MHz_2x The 502nd to 756th elements in LTF 80MHz_2x (757:1001) represents the sequence LTF 80MHz_2x From the 757th element to the 1001th element, the sequence LTF80MHz_2x is the basic LTF sequence of the 2x mode, 0 23 Indicates that 23 consecutive elements in the LTF sequence are 0.

[0070] In a third aspect, an embodiment of the present application provides a communication method, which can be applied to a first communication device, which can be a Wi-Fi device or a Wi-Fi chip or module. The method includes:

[0071] According to the bandwidth, the size of the resource unit (RU) / multiple resource units (MRU) and the RU / MRU position, the sequence segment in the LTF sequence corresponding to the RU position / the MRU position is mapped onto the subcarrier in the RU / the MRU; the LTF sequence is sent; wherein the RU / the MRU is located within the bandwidth, and the RU / the MRU includes multiple continuous subcarriers.

[0072] or,

[0073] According to the bandwidth, the sequence segments in the LTF sequence corresponding to the subcarrier positions in the RU / the subcarrier positions in the MRU included in the bandwidth are mapped onto the subcarriers in the RU / the MRU; the LTF sequence is sent; wherein the RU / the MRU is located within the bandwidth, and the RU / the MRU includes multiple continuous subcarriers.

[0074] With reference to the third aspect, in one possible implementation, when the bandwidth is greater than 320 MHz, the LTF sequence in the 2x mode is any one of the following:

[0075] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0076] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0077] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0078] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0079] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0080] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0081] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0082] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0083] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0084] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x(246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0085] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0086] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0087] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0088] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0089] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0090] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0091] ±{LTF 80MHz_2x(1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0092] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0093] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0094] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0095] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0096] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0097] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0098] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0099] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0100] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0101] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0102] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0103] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0104] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x(757:1001),0 23 ,

[0105] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0106] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)};

[0107] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0108] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0109] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0110] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0111] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x(502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0112] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0113] ±{-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0114] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0115] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0116] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0117] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0118] -LTF 80MHz_2x (1:245),LTF 80MHz_2x(246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[0119] Among them, LTF 80MHz_2x (1:245) indicates the sequence LTF 80MHz_2x The first to the 245th element in LTF 80MHz_2x (246:500) represents the sequence LTF 80MHz_2x The 246th to 500th elements in LTF 80MHz_2x (502:756) represents the sequence LTF 80MHz_2x The 502nd to 756th elements in LTF 80MHz_2x (757:1001) represents the sequence LTF 80MHz_2x From the 757th element to the 1001th element, the sequence LTF 80MHz_2x is the basic LTF sequence of the 2x mode, 0 23 Indicates that 23 consecutive elements in the LTF sequence are 0.

[0120] In conjunction with the third aspect, in a possible implementation manner, mapping the sequence segment corresponding to the RU position / the MRU position in the LTF sequence to the subcarrier in the RU / the MRU according to the bandwidth, the size of the resource unit (RU) / multiple resource units (MRUs), and the RU / MRU position includes:

[0121] According to the bandwidth, the matrix corresponding to the pilot rotation, the size of the RU / MRU and the RU / MRU position, the sequence segment corresponding to the RU position / the MRU position in the LTF sequence is mapped to the subcarriers in the RU / the MRU.

[0122] The LTF sequence provided in the embodiment of the present application takes into account both the multiple RUs or MRUs that may appear in the PPDU and the pilot rotation (such as the P matrix or the R matrix, etc.), so that the LTF sequence can be effectively applied to various situations where the bandwidth of the PPDU is greater than 320MHz, and is compatible with various RUs or MRUs existing in the 802.11be protocol or the 802.11bn protocol, etc.

[0123] In conjunction with the third aspect, in a possible implementation manner, mapping, according to the bandwidth, a sequence segment in the LTF sequence corresponding to the subcarrier position in the RU / the subcarrier position in the MRU included in the bandwidth onto the subcarrier in the RU / the MRU includes:

[0124] According to the sequence corresponding to the bandwidth and the pilot rotation, the sequence segments in the LTF sequence corresponding to the subcarrier positions in the RU / the subcarrier positions in the MRU included in the bandwidth are mapped onto the subcarriers in the RU / the MRU.

[0125] In a fourth aspect, an embodiment of the present application provides a communication method, which can be applied to a second communication device, which can be a Wi-Fi device or a Wi-Fi chip or module. The method includes:

[0126] Receive an LTF sequence; determine an LTF sequence corresponding to the RU / MRU based on the bandwidth, the size of the RU / MRU, and the RU / MRU position, wherein the LTF sequence is used to estimate the channel of the RU / MRU, wherein the RU / the MRU is located within the bandwidth and the RU / the MRU includes multiple consecutive subcarriers.

[0127] or,

[0128] Receive an LTF sequence; determine an LTF sequence corresponding to the RU / MRU based on the bandwidth and the subcarrier position in the RU / MRU included in the bandwidth, wherein the RU / MRU is located within the bandwidth and includes multiple consecutive subcarriers.

[0129] When the bandwidth is greater than 320 MHz, the LTF sequence in the 2x mode is as shown in the third aspect.

[0130] In combination with the fourth aspect, in a possible implementation method, determining the LTF sequence corresponding to the RU / MRU based on the bandwidth, the size of the RU / MRU and the position of the RU / MRU includes: determining the LTF sequence corresponding to the RU / MRU based on the bandwidth, the matrix corresponding to the pilot rotation, the size of the RU / MRU and the position of the RU / MRU.

[0131] In combination with the fourth aspect, in a possible implementation method, according to the bandwidth, and the subcarrier position in the RU included in the bandwidth / the subcarrier position of the MRU, determining the LTF sequence corresponding to the RU / MRU includes: according to the bandwidth, the matrix corresponding to the pilot rotation, and the subcarrier position in the RU included in the bandwidth / the subcarrier position of the MRU, determining the LTF sequence corresponding to the RU / MRU

[0132] In a fifth aspect, an embodiment of the present application provides a first communication device for executing the method in the first aspect or the third aspect or any possible implementation. The first communication device includes a unit having a function of executing the method in the first aspect or the third aspect or any possible implementation.

[0133] In a sixth aspect, an embodiment of the present application provides a second communication device for executing the method in the second aspect or the fourth aspect or any possible implementation. The second communication device includes a unit having a function of executing the method in the second aspect or the fourth aspect or any possible implementation.

[0134] In a seventh aspect, an embodiment of the present application provides a first communication device, comprising a processor configured to execute the method described in the first aspect, the third aspect, or any possible implementation. The processor is configured to execute a program stored in a memory, and when the program is executed, the method described in the first aspect, the third aspect, or any possible implementation is executed.

[0135] In a possible implementation, the memory is located outside the first communication device.

[0136] In a possible implementation, the memory is located within the first communication device.

[0137] In the embodiment of the present application, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together. For example, the first communication device may be a chip.

[0138] In a possible implementation, the first communication device further includes a transceiver, where the transceiver is configured to receive information or send information.

[0139] In an eighth aspect, an embodiment of the present application provides a second communication device, comprising a processor configured to execute the method described in the second aspect, the fourth aspect, or any possible implementation. The processor is configured to execute a program stored in a memory, and when the program is executed, the method described in the second aspect, the fourth aspect, or any possible implementation is executed.

[0140] In a possible implementation, the memory is located outside the second communication device.

[0141] In a possible implementation, the memory is located within the second communication device.

[0142] In the embodiment of the present application, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together. Exemplarily, the second communication device may be a chip.

[0143] In a possible implementation, the second communication device further includes a transceiver, where the transceiver is configured to receive information or send information.

[0144] In the ninth aspect, an embodiment of the present application provides a first communication device, which includes a logic circuit and an interface, and the logic circuit and the interface are coupled; the interface is used to input and / or output information, and the logic circuit is used to execute the method described in the first aspect or the third aspect or any possible implementation method.

[0145] In a possible implementation, the interface being used to output information includes: the interface being used to output a PPDU. Exemplarily, the logic circuit is used to generate a PPDU.

[0146] In the tenth aspect, an embodiment of the present application provides a second communication device, which includes a logic circuit and an interface, and the logic circuit and the interface are coupled; the interface is used to input and / or output information, and the logic circuit is used to execute the method described in the second aspect or the fourth aspect or any possible implementation method.

[0147] In a possible implementation, the interface being used to input information includes: the interface being used to input a PPDU. Exemplarily, the logic circuit is used to parse the PPDU.

[0148] In the eleventh aspect, an embodiment of the present application provides a computer-readable storage medium, which is used to store a computer program. When the computer program is run on a computer, the method shown in the first aspect, second aspect, third aspect, fourth aspect or any possible implementation method is executed.

[0149] In the twelfth aspect, an embodiment of the present application provides a computer program product, which includes a computer program or computer code, and when it runs on a computer, enables the method shown in the above-mentioned first aspect, second aspect, third aspect, fourth aspect or any possible implementation method to be executed.

[0150] In a thirteenth aspect, an embodiment of the present application provides a computer program. When the computer program runs on a computer, the method shown in the above-mentioned first aspect, second aspect, third aspect, fourth aspect or any possible implementation is executed.

[0151] In a fourteenth aspect, an embodiment of the present application provides a communication system, which includes a first communication device and a second communication device.

[0152] In one possible implementation, the first communication device is used to execute the method shown in the above-mentioned first aspect or any possible implementation of the first aspect, and the second communication device is used to execute the method shown in the above-mentioned second aspect or any possible implementation of the second aspect.

[0153] In another possible implementation, the first communication device is used to execute the method shown in the third aspect or any possible implementation of the third aspect, and the second communication device is used to execute the method shown in the fourth aspect or any possible implementation of the fourth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0154] FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0155] FIG2a is a schematic diagram of a PPDU format provided in an embodiment of the present application;

[0156] FIG2 b is a schematic diagram of a PPDU format provided in an embodiment of the present application;

[0157] FIG3 is a flow chart of a communication method provided in an embodiment of the present application;

[0158] Figures 4a to 4g are schematic diagrams of an MRU provided in an embodiment of the present application;

[0159] Figures 5a to 5d are schematic diagrams of an MRU provided in an embodiment of the present application;

[0160] FIG6 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0161] Figures 7a and 7b are schematic structural diagrams of a communication device provided in an embodiment of the present application;

[0162] FIG8 is a schematic structural diagram of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0163] To facilitate understanding of the technical solution of the present application, the present application will be further described below with reference to the accompanying drawings.

[0164] The terms "first" and "second" in the specification, claims, and drawings of this application are used only to distinguish different objects and are not used to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or device.

[0165] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It will be understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0166] In this application, "at least one (item)" means one or more, "more than one" means two or more, "at least two (items)" means two or three and more than three, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. "Or" means that two relationships can exist, such as only A exists, only B exists; when A and B are not mutually exclusive, it can also mean that three relationships exist, such as only A exists, only B exists, and A and B exist at the same time. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c".

[0167] The embodiment of the present application provides a communication method and apparatus, wherein the LTF sequence used in the PPDU involved in the communication method can effectively reduce the PAPR of the LTF signal in a large bandwidth scenario, thereby effectively reducing the error in signal estimation. The LTF sequence can be effectively applied to situations where the bandwidth of the PPDU is greater than 320 MHz. The LTF sequence provided in the embodiment of the present application takes into account both the multiple RUs or MRUs that may appear in the PPDU and the pilot rotation (such as the P matrix or the R matrix, etc.), so that the LTF sequence can be effectively applied to various situations where the bandwidth of the PPDU is greater than 320 MHz, and is compatible with various RUs or MRUs existing in the 802.11be protocol or the 802.11bn protocol, etc. Since multiple RUs or MRUs are taken into account, when a user on any RU or MRU performs wireless communication, the user's PAPR is avoided from being too large to affect the transmission performance, effectively reducing the requirements for linear power amplifier devices and improving the throughput performance of a single user.

[0168] The following introduces the communication system involved in the embodiments of the present application.

[0169] The technical solutions provided in the embodiments of the present application can be applied to WLAN systems, such as Wi-Fi, etc. For example, the methods provided in the embodiments of the present application can be applied to the IEEE 802.11 series of protocols, such as 802.11a / b / g protocols, 802.11n protocols, 802.11ac protocols, 802.11ax protocols, 802.11be protocols, 802.11bn protocols or next-generation protocols, etc., which are not listed one by one. The technical solutions provided in the embodiments of the present application can also be applied to wireless personal area networks (WPANs) based on millimeter wave (MMW) and ultra-wideband (UWB) technologies. For example, the methods provided in the embodiments of the present application can be applied to the IEEE 802.15 series of protocols, such as 802.15.4a protocols, 802.15.4z protocols or 802.15.4ab protocols, or a future generation of UWB WPAN protocols, etc., which are not listed one by one. The technical solutions provided in the embodiments of the present application can also be applied to the following communication systems, for example, the Internet of Things (IoT) system, the Vehicle to X (V2X) system, the Narrow Band Internet of Things (NB-IoT) system, the Long Term Evolution (LTE) system, the fifth generation (5G) communication system, and new communication systems that will emerge in the future development of communications.

[0170] WLAN systems can provide high-speed and low-latency transmission. As WLAN application scenarios continue to evolve, WLAN systems will be applied to more scenarios or industries, such as the Internet of Things industry, the Internet of Vehicles industry, the banking industry, corporate offices, sports stadiums and exhibition halls, concert halls, hotel rooms, dormitories, wards, classrooms, supermarkets, squares, streets, production workshops and warehouses, etc. Of course, devices that support WLAN communication or perception (such as access points or stations) can be sensor nodes in smart cities (such as smart water meters, smart electricity meters, and smart air detection nodes), smart devices in smart homes (such as smart cameras, projectors, displays, TVs, speakers, refrigerators, washing machines, etc.), nodes in the Internet of Things, entertainment terminals (such as wearable devices such as augmented reality (AR) and virtual reality (VR)), smart devices in smart offices (such as printers, projectors, loudspeakers, speakers, etc.), Internet of Vehicles devices, infrastructure in daily life scenarios (such as vending machines, self-service navigation counters in supermarkets, self-service checkout equipment, self-service ordering machines, etc.), and equipment in large sports and music venues.

[0171] Although the embodiments of the present application mainly take WLAN as an example, especially the network applied to the IEEE 802.11 series of standards. The embodiments of the present application can support Wi-Fi 8, which can also be called ultra high reliability (UHR) or ultra high reliability and throughput (UHRT), which are not listed here one by one. The various aspects involved in the embodiments of the present application can be extended to other networks that adopt various standards or protocols. For example, Bluetooth, high performance radio LAN (HIPERLAN) (a wireless standard similar to the IEEE 802.11 standard, mainly used in Europe) and wide area network (WAN) or other networks now known or developed later.

[0172] In one possible implementation, the method provided in the embodiment of the present application may be implemented by a communication device in a communication system. For example, the communication device may be an access point (AP) or a station (STA).

[0173] An access point is a device with wireless communication capabilities that supports communication or sensing using WLAN protocols. It has the ability to communicate or sense with other devices in a WLAN network (such as non-AP STAs or other access points). Of course, it can also have the ability to communicate or sense with other devices. Alternatively, an access point acts as a bridge between a wired network and a wireless network, primarily connecting wireless network clients and then connecting the wireless network to the Ethernet. In a WLAN system, an access point can be referred to as an access point station (AP STA). This device with wireless communication capabilities can be a complete device or a chip, processing system, or functional module installed in the complete device. Devices equipped with these chips, processing systems, or functional modules can implement the methods and functions of the embodiments of the present application under the control of these chips, processing systems, or functional modules. The AP in the embodiments of the present application is a device that provides services for non-AP STAs and can support the 802.11 series of protocols or subsequent protocols. For example, an access point can be an access point for a terminal (such as a mobile phone) to enter a wired (or wireless) network. It is primarily deployed in homes, buildings, and campuses, with a typical coverage radius of tens to hundreds of meters. Of course, it can also be deployed outdoors. For another example, an AP may be a communication entity such as a communication server, router, switch, or bridge; an AP may include various forms of macro base stations, micro base stations, and relay stations. Of course, an AP may also be a chip, processing system, or module in any of the aforementioned devices, thereby implementing the methods and functions of the embodiments of the present application.

[0174] A STA is a device with wireless communication capabilities that supports communication or perception using the WLAN protocol and has the ability to communicate or perceive other non-AP STAs or access points in the WLAN network. In a WLAN system, a station can be referred to as a non-access point station (non-AP STA). For example, a STA is any user communication device that allows a user to communicate or perceive with an AP and then communicate with a WLAN. The device with wireless communication capabilities can be a complete device, or a chip, processing system, or functional module installed in the complete device. The device installed with these chips, processing systems, or functional modules can implement the methods and functions of the embodiments of the present application under the control of the chip, processing system, or functional module. For example, a STA can be a wireless communication chip, a wireless sensor, or a wireless communication terminal, and can also be referred to as a user. For another example, a STA can be a mobile phone that supports Wi-Fi communication capabilities, a tablet that supports Wi-Fi communication capabilities, a set-top box that supports Wi-Fi communication capabilities, a smart TV that supports Wi-Fi communication capabilities, a smart wearable device that supports Wi-Fi communication capabilities, an in-vehicle communication device that supports Wi-Fi communication capabilities, and a computer that supports Wi-Fi communication capabilities. Of course, STA can also be a chip, processing system, or module in the various forms of devices mentioned above, so as to implement the methods and functions of the embodiments of the present application.

[0175] Exemplarily, the communication system to which the method provided in the embodiments of the present application can be applied may include access points and stations. For example, the embodiments of the present application may be applicable to scenarios of communication or perception between APs and STAs, between APs and APs, or between STAs and STAs in a WLAN, and the embodiments of the present application are not limited thereto. Optionally, the AP may communicate or perceive with a single STA, or the AP may communicate or perceive with multiple STAs simultaneously. Specifically, communication or perception between the AP and multiple STAs can be further divided into downlink transmission in which the AP sends signals to multiple STAs simultaneously, and uplink transmission in which multiple STAs send signals to the AP. WLAN communication protocols may be supported between the AP and STAs, between APs and APs, and between STAs. The communication protocols may include IEEE 802.11 series protocols, such as 802.11n / 802.11ac / 802.11ax / 802.11be / 802.11bn protocols, and of course, also applicable to protocols after 802.11bn.

[0176] Figure 1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application. The communication system may include one or more APs and one or more STAs. Figure 1 shows an access point such as AP1, and three stations such as STA1, STA2, and STA3. Exemplarily, the method provided in an embodiment of the present application may be applicable to data communication between an AP and one or more STAs (such as the communication between AP1 and STA1 as shown in Figure 1, or the communication between AP1 and STA1 and STA2), or applicable to communication between APs (such as the communication between AP1 and AP2 as shown in Figure 1), or applicable to communication between STAs (such as the communication between STA2 and STA3 as shown in Figure 1). The method provided in an embodiment of the present application may be applicable to, but not limited to: single-user uplink / downlink transmission, multi-user uplink / downlink transmission, vehicle-to-everything (V2X, X can represent anything), and device-to-device (D2D). For example, the V2X may include: vehicle to vehicle (V2V), vehicle to infrastructure (V2I), vehicle to pedestrian (V2P) or vehicle to network (V2N) communication, etc.

[0177] It is understood that the example of a mobile phone as a STA and a router as an AP in Figure 1 does not limit the types of APs and STAs in the embodiments of this application. Furthermore, Figure 1 only illustrates one AP and three STAs, but the number of APs or STAs can be greater or less, and this is not limited in the embodiments of this application.

[0178] From the perspectives of sending and receiving PPDUs, the first communication device described below can be understood as a communication device that sends PPDUs, and the second communication device can be understood as a communication device that receives PPDUs. As an example, the first communication device and the second communication device can be Wi-Fi chips, modules, or processing systems, etc., provided in different Wi-Fi devices. As another example, the first communication device can be an AP, and the second communication device can be a STA. As another example, the first communication device and the second communication device can both be STAs or both APs. As another example, the first communication device can be a STA, and the second communication device can be an AP. As another example, at least one of the first communication device and the second communication device can be a multi-link device (MLD), etc., which will not be listed one by one in the embodiments of this application. Exemplarily, a multi-link device (MLD) refers to a device that simultaneously has multiple stations (such as APs or non-AP STAs), each operating on different frequency bands or channels. A multi-link device includes multiple subordinate stations, which can be physical stations or logical stations. Each station can operate on a link, a frequency band, or a channel, etc. The above-mentioned affiliated sites may be APs or non-AP STAs. A multi-link device (such as a non-AP MLD or an AP MLD) may be a communication device with wireless communication capabilities. The communication device may be a complete device, or may be a chip, processing system, or module installed in the complete device. Devices installed with these chips, processing systems, or modules may implement the methods and functions of the embodiments of the present application under the control of these chips, processing systems, or modules. The multi-link device may implement wireless communication in accordance with the 802.11 series of protocols, thereby enabling communication with other devices. The other devices shown here may be multi-link devices or may not be multi-link devices. The frequency bands in which the multi-link device operates may include, but are not limited to, sub 1GHz, 2.4GHz, 5GHz, 6GHz, etc., which are not listed here one by one.

[0179] It can be understood that the embodiment of the present application describes the method provided by the embodiment of the present application based on the first communication device and the second communication device. However, during the process of transmitting the PPDU, the first communication device and the second communication device can also forward the PPDU through other devices, such as forwarding the PPDU between the first communication device and the second communication device through a forwarding device. The embodiment of the present application does not limit other devices other than the first communication device and the second communication device.

[0180] The following describes the communication method provided in the embodiments of the present application.

[0181] To meet requirements for higher throughput and wider coverage, the IEEE 802.11be standard defines two PPDU formats: the very high-throughput multi-user PHY protocol data unit (EHT MU PPDU) and the very high-throughput trigger-based PHY protocol data unit (EHT TB PPDU). For example, Figure 2a shows the structure of an EHT MU PPDU, and Figure 2b shows the structure of an EHT TB PPDU.

[0182] As shown in Figure 2a, the EHT MU PPDU may include a legacy short training field (L-STF), a legacy long training field (L-LTF), a legacy signaling (L-SIG) field, a repeated legacy signaling (RL-SIG) field, a universal signaling (U-SIG) field, an EHT-SIG field, an EHT-STF, an EHT-LTF, a data field, and a packet extension (PE). As shown in Figure 2b, the EHT TB PPDU includes an L-STF, an L-LTF, an L-SIG field, an RL-SIG field, a U-SIG field, an EHT-STF, an EHT-LTF, a data field, and a PE. The EHT-LTF can be used by the receiving end (i.e., the communication device receiving the PPDU) for channel estimation. The time length shown in Figures 2a and 2b is the duration of the field, or the length of the orthogonal frequency division multiplexing (OFDM) symbol corresponding to the field. Each field shown in Figure 2a or 2b can occupy one or more OFDM symbols, and an OFDM symbol can occupy 4 microseconds (us). The duration of an OFDM symbol shown here is only an example and should not be understood as limiting the embodiments of the present application.

[0183] For example, one EHT-LTF in a PPDU may occupy one OFDM symbol, and the EHT-LTF may be repeated in the time domain. As shown in Figures 2a and 2b above, the length of the OFDM symbol occupied by the EHT-LTF may be related to the guard interval (GI) and the LTF mode. The embodiment of the present application does not limit the number of OFDM symbols occupied by the fields in the PPDU.

[0184] For example, EHT-LTF modes can be divided into three types: 1xLTF, 2xLTF, and 4xLTF. 1xLTF refers to an LTF sequence in 1x mode; 2xLTF refers to an LTF sequence in 2x mode; and 4xLTF refers to an LTF sequence in 4x mode.

[0185] For the IEEE 802.11be standard, the maximum bandwidth for transmitting PPDU is 320MHz, that is, the maximum supported bandwidth of PPDU is 320MHz. In a 320MHz PPDU, 2x EHT-LTF sequence (as shown below) -2036,2036 ) can be as follows:

[0186] EHTLTF -2036,2036 =

[0187] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0188] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0189] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0190] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}

[0191] Among them, 0 23 Indicates that 23 consecutive values ​​are 0, or that 23 consecutive elements in the EHT-LTF sequence are all 0. 80MHz_2x (a:b) represents the sequence LTF80MHz_2x From the ath to the bth element in the sequence LTF 80MHz_2x It may be a basic LTF sequence corresponding to a basic sub-channel. For example, the bandwidth of the basic sub-channel may be 80 MHz.

[0192] For example, the basic LTF sequence corresponding to the basic subchannel (ie, LTF 80MHz_2x ) can be as follows:

[0193] LTF 80MHz_2x =

[0194] {+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,

[0195] +1,0,+1,0,-1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,+1,0,

[0196] +1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,+1,0,

[0197] +1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,0,

[0198] +1,0,-1,0,+1,0,+1,0,-1,0,-1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,

[0199] –1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,

[0200] +1,0,+1,0,-1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,

[0201] +1,0,-1,0,+1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,

[0202] +1,0,-1,0,-1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,

[0203] +1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,0,

[0204] –1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,

[0205] –1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,+1,0,

[0206] +1,0,+1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,

[0207] –1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,

[0208] +1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,

[0209] +1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,-1,0,

[0210] –1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,-1,0,-1,0,+1,0,0,0,0,0,0,0,-1,0,-1,0,-1,

[0211] 0,-1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,

[0212] 0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,+1,0,-1,

[0213] 0,-1,0,+1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,-1,

[0214] 0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,

[0215] 0,+1,0,-1,0,+1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,

[0216] 0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,

[0217] 0,+1,0,+1,0,-1,0,+1,0,-1,0,-1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,

[0218] 0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,

[0219] 0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,

[0220] 0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,-1,0,+1,

[0221] 0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,

[0222] 0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,+1,0,-1,0,+1,

[0223] 0,+1,0,-1,0,-1,0,+1,0,+1,0,+1,0,-1,0,-1,0,-1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,

[0224] 0,+1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,+1,0,-1,0,-1,0,-1,0,-1,0,+1,0,+1,

[0225] 0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,+1,0,+1,0,+1,0,+1,0,-1,0,-1,0,+1,

[0226] 0,-1,0,+1,0,+1,0,+1,0,+1,0,-1,0,+1,0,-1,0,-1,0,-1,0,+1,0,+1,0,-1,0,+1,0,+1,

[0227] 0,+1,0,+1,0,+1,0,–1,0,+1,0,+1}.

[0228] The LTF shown above 80MHz_2x This is merely an example. As standards evolve, the specific content of the basic LTF sequence may be updated, and this is not limited in the present embodiment. The basic LTF sequence can be used to represent LTF sequences at different bandwidths. As the basic LTF sequence changes, the representation of the LTF sequence may also change. Therefore, the present embodiment does not limit the basic LTF sequence. The description of the basic subchannel and basic LTF sequence here also applies below.

[0229] The LTF sequence shown above is not applicable to the situation where the bandwidth of the PPDU is greater than 320MHz. Therefore, an embodiment of the present application provides a communication method. The LTF sequence provided by this method can be effectively applied to the situation where the bandwidth of the PPDU is greater than 320MHz, and can be compatible with various RUs or MRUs when the bandwidth of the PPDU is greater than 320MHz.

[0230] FIG3 is a flow chart of a communication method provided by an embodiment of the present application. For relevant descriptions of the first communication device and the second communication device, reference can be made to the description of the communication system above and will not be described in detail here. As shown in FIG3 , the method includes:

[0231] 301. A first communication device generates a PPDU, where the PPDU includes an LTF carrying an LTF sequence. The LTF sequence is determined based on a basic LTF sequence corresponding to a basic subchannel. The length of the LTF sequence corresponds to a bandwidth of the PPDU, and the bandwidth of the PPDU is greater than 320 MHz.

[0232] The following is a detailed introduction to each term involved in step 301.

[0233] First, PPDU

[0234] PPDU may include LTF. For example, the LTF may be EHT-LTF, UHR-LTF, or next-generation LTF, etc. The specific name of the LTF is not limited in the embodiment of the present application. For the convenience of description, when referring to specific examples below, UHR-LTF is used as an example. In addition to the above-mentioned LTF, PPDU may also include at least one of the following: L-STF, L-LTF, L-SIG field, RL-SIG field, U-SIG field, data field. For example, for EHT PPDU or EHT TB PPDU, PPDU may also include EHT-STF. For example, for UHR PPDU or UHR TB PPDU, PPDU may also include UHR-STF. For other fields in PPDU, the embodiment of the present application does not limit it.

[0235] For example, each field in a PPDU may occupy one or more OFDM symbols in the time domain. An LTF, as provided in an embodiment of the present application, may occupy one or more OFDM symbols. The number of OFDM symbols occupied by the LTF may be determined based on the LTF mode, such as depending on the GI and LTF mode. The embodiment of the present application does not limit the number of OFDM symbols occupied by different fields in a PPDU.

[0236] The bandwidth of the PPDU is greater than 320MHz. For example, the bandwidth of the PPDU can also be referred to as the total transmission bandwidth for transmitting the PPDU. The total transmission bandwidth of the PPDU can also be referred to as the PPDU bandwidth, etc. The specific description method of the bandwidth is not limited in the embodiment of the present application. For example, in the frequency domain dimension, the bandwidth of the PPDU may include N subcarriers (or the bandwidth of the PPDU is divided into N subcarriers), where N is a positive integer. The N subcarriers may include pilot subcarriers, data subcarriers, DC subcarriers and protection subcarriers. For example, the protection subcarriers and DC subcarriers may not carry signals, and the values ​​of the signals carried by the protection subcarriers and DC subcarriers may be considered to be 0. The pilot subcarrier is used to carry the pilot signal, and the data subcarrier is used to carry the payload information.

[0237] For example, 80 MHz may include 1024 subcarriers. For example, 80 MHz includes 1024 subcarriers, such as a 996-tone RU, 5 DC subcarriers, and 23 protection subcarriers. N = (PPDU bandwidth / 80) * 1024. The relationship between the PPDU bandwidth and the number of subcarriers can be shown as follows:

[0238] As an example, the bandwidth of the PPDU may be 480 MHz, such as the bandwidth of the PPDU may include 6144 (ie, 1024*6) subcarriers.

[0239] When the LTF sequence is a 2x mode LTF sequence, among the 6144 subcarriers, 1 subcarrier is used for transmission among the two adjacent subcarriers except the direct current (DC) subcarrier, the null subcarrier and the protection subcarrier. The "used for transmission" shown here means that the subcarrier used for transmission can carry a non-zero value after modulation. Exemplarily, there can be 23 protection subcarriers, 23 DC subcarriers, and (23×4+5*6) null subcarriers among the 6144 subcarriers. There is no limitation on the number and position of the protection subcarriers and DC subcarriers included in the 6144 subcarriers. Exemplarily, the first 12 subcarriers in the bandwidth of the PPDU can be protection subcarriers, and the last 11 subcarriers can be protection subcarriers. Exemplarily, the 23 subcarriers in the middle of the bandwidth of the PPDU can be DC subcarriers. Exemplarily, more than 4 consecutive subcarriers with a value of 0 except the DC subcarrier and the protection subcarrier in the bandwidth of the PPDU can be null subcarriers.

[0240] As another example, the bandwidth of the PPDU may be 640 MHz, and the bandwidth of the PPDU may include 8192 (1024*8) subcarriers. When the LTF sequence is a 2x mode LTF sequence, among the 8192 subcarriers, 1 subcarrier is used for transmission among the two adjacent subcarriers except the DC subcarrier, the empty subcarrier, and the protection subcarrier. Exemplarily, there may be 23 protection subcarriers, 23 DC subcarriers, and (23×6+5*8) empty subcarriers among the 8192 subcarriers. There is no limitation on the number and position of the protection subcarriers and DC subcarriers included in the 8192 subcarriers. Exemplarily, the first 12 subcarriers in the bandwidth of the PPDU may be protection subcarriers, and the last 11 subcarriers may be protection subcarriers. Exemplarily, the 23 subcarriers in the middle of the bandwidth of the PPDU may be DC subcarriers. Exemplarily, in the bandwidth of the PPDU, more than four consecutive subcarriers with a value of 0 except the DC subcarrier and the protection subcarrier can be empty subcarriers.

[0241] That one of the two adjacent subcarriers is used for transmission may also be represented as follows: the value carried by one of the two adjacent subcarriers is 0, and the value carried by the other of the two adjacent subcarriers may be a non-zero value.

[0242] The PPDU bandwidths listed in the embodiments of the present application are merely examples and should not be construed as limiting the embodiments of the present application.

[0243] Second, basic subchannel and basic LTF sequence

[0244] For example, the bandwidth of the basic sub-channel may be 80 MHz. The basic LTF sequence may refer to the sequence corresponding to the above 80 MHz (ie, LTF 80MHz_2x )’s specific content will not be repeated here.

[0245] Third, LTF and LTF sequence

[0246] LTF can be used to carry LTF sequence. For example, LTF can be obtained by the first communication device modulating the LTF sequence to the corresponding frequency domain subcarrier and then transforming it through inverse discrete Fourier transform (IDFT) (such as inverse fast Fourier transform (IFFT)). For another example, the first communication device modulates the LTF sequence to the corresponding frequency domain subcarrier to form a frequency domain signal, and then forms a time domain signal through IFFT. The time domain signal is formed into an OFDM symbol after inserting a guard interval and adding a window (insert GI and window). For the specific description between LTF and LTF sequence, please refer to the relevant standards and will not be described in detail here.

[0247] For example, the LTF sequence can be determined based on the basic LTF sequence. As an example, the bandwidth of the PPDU is 640MHz, and the LTF sequence (hereinafter referred to as UHRLTF -4084,4084 The LTF sequence may be represented as shown in sequence (1). The bandwidth of the PPDU is 640 MHz, and the bandwidth of the PPDU may include 8192 subcarriers. In addition to the 23 subcarriers, there are 8192-23=8169 subcarriers. The indexes of the 8169 subcarriers may range from -4084 to 4084, and the indexes may be represented as {-4084, 4084}. As another example, the bandwidth of the PPDU is 480 MHz, and the LTF sequence may be represented as shown in sequence (2). The bandwidth of the PPDU is 480 MHz, and the bandwidth of the PPDU may include 6144 subcarriers. In addition to the 23 subcarriers, there are 6144-23=6121 subcarriers. The indexes of the 6121 subcarriers may range from -3060 to 3060, and the indexes may be represented as {-3060, 3060}.

[0248] LTF -4084,4084 =

[0249] {c1*LTF 80MHz_2x (1:245),c2*LTF 80MHz_2x (246:500),0,c3*LTF 80MHz_2x (502:756),c4*LTF 80MHz_2x (757:1001),0 23 ,

[0250] c5*LTF 80MHz_2x (1:245),c6*LTF 80MHz_2x (246:500),0,c7*LTF 80MHz_2x (502:756),c8*LTF 80MHz_2x (757:1001),023 ,

[0251] c9*LTF 80MHz_2x (1:245),c 10 *LTF 80MHz_2x (246:500),0,c 11 *LTF 80MHz_2x (502:756),c 12 *LTF 80MHz_2x (757:1001),0 23 ,

[0252] c 13 *LTF 80MHz_2x (1:245),c 14 *LTF 80MHz_2x (246:500),0,c 15 *LTF 80MHz_2x (502:756),c 16 *LTF 80MHz_2x (757:1001),0 23 ,

[0253] c 17 *LTF 80MHz_2x (1:245),c 18 *LTF 80MHz_2x (246:500),0,c 19 *LTF 80MHz_2x (502:756),c 20 *LTF 80MHz_2x (757:1001),0 23 ,

[0254] c 21 *LTF 80MHz_2x (1:245),c 22 *LTF 80MHz_2x (246:500),0,c 23 *LTF 80MHz_2x (502:756),c 24 *LTF 80MHz_2x (757:1001),0 23 ,

[0255] c 25 *LTF 80MHz_2x (1:245),c 26 *LTF 80MHz_2x (246:500),0,c 27 *LTF 80MHz_2x (502:756),c 28 *LTF80MHz_2x (757:1001),0 23 ,

[0256] c 29 *LTF 80MHz_2x (1:245),c 30 *LTF 80MHz_2x (246:500),0,c 31 *LTF 80MHz_2x (502:756),c 32 *LTF 80MHz_2x (757:1001)}(1)

[0257] Among them, c j The modulus value of is 1. j =-1 or c j =1, j=1,2,…,32. LTF 80MHz_2x (a:b) represents the sequence LTF 80MHz_2x From the ath to the bth element in . 23 It means that 23 consecutive values ​​are 0, or it means that 23 consecutive elements in the LTF sequence are all 0. The subcarrier where the 23 consecutive 0s are located can be a null subcarrier (nullsubcarrier). For example, for the basic subchannel (such as a bandwidth of 80MHz), the first 12 subcarriers and the last 11 subcarriers in the subcarriers corresponding to the basic subchannel are all protection subcarriers. When there are two 80MHz, the values ​​carried by 23 subcarriers are all 0, so these 23 subcarriers are called null subcarriers. Since there are 8 80MHz in 640MHz, and the first 12 subcarriers and the last 11 subcarriers of the 640MHz are protection subcarriers, there are 7 0s in the LTF sequence. 23 The 640MHz guard subcarrier is not shown in the above sequence (1). When the index or position of the guard subcarrier changes, the specific form of the above sequence (1) may also change accordingly, such as according to the specific form of the basic LTF sequence and the index of the guard subcarrier.

[0258] LTF -3060,3060 =

[0259] {c1*LTF 80MHz_2x (1:245),c2*LTF 80MHz_2x (246:500),0,c3*LTF 80MHz_2x (502:756),c4*LTF 80MHz_2x (757:1001),0 23 ,

[0260] c5*LTF 80MHz_2x(1:245), c6 * LTF 80MHz_2x (246:500), 0, c7 * LTF 80MHz_2x (502:756), c8 * LTF 80MHz_2x (757:1001), 0 23 ,

[0261] c9 * LTF 80MHz_2x (1:245), c 10 * LTF 80MHz_2x (246:500), 0, c 11 * LTF 80MHz_2x (502:756), c 12 * LTF 80MHz_2x (757:1001), 0 23 ,

[0262] c 13 * LTF 80MHz_2x (1:245), c 14 * LTF 80MHz_2x (246:500), 0, c 15 * LTF 80MHz_2x (502:756), c 16 * LTF 80MHz_2x (757:1001), 0 23 ,

[0263] c 17 * LTF 80MHz_2x ((1:245), c 18 * LTF 80MHz_2x (246:500), 0, c e 19 * LTF 80MHz_2x (502:756), c 20 * LTF 80MHz_2x (757:1001), 0 23 ,

[0264] c 21 * LTF 80MHz_2x (1:245), c 22 * LTF 80MHz_2x (246:500), 0, c 23 * LTF 80MHz_2x (502:756), c 24 * LTF 80MHz_2x (757:1001)}(2)

[0265] Among them, the modulus value of c j is 1. For example, if c j = -1 or c j=1, j = 1, 2, ..., 24. Other explanations of sequence (2) can refer to sequence (1) and will not be repeated here. Although both sequences (1) and (2) have c j , j = 12, ..., 24, but does not represent the c in sequence (1) and sequence (2) j The values ​​are exactly the same.

[0266] Fourth, the unit subchannel, the sequence corresponding to the unit subchannel, and the rotation factor sequence

[0267] Exemplarily, the LTF sequence can be determined based on the sequence corresponding to the unit subchannel, and the sequence corresponding to the unit subchannel can be determined based on the basic LTF sequence. For example, the bandwidth of the unit subchannel can be any of the following: 20MHz, 40MHz, 80MHz, 160MHz, 320MHz. Generally speaking, the smaller the bandwidth of the unit subchannel, the more rotation factors of the sequence corresponding to the unit subchannel, that is, the longer the length of the rotation factor sequence, and thus the better the PAPR performance of the LTF sequence. For example, when the bandwidth of the PPDU is constant, the length of the rotation factor sequence becomes longer, which means that the partial bandwidth corresponding to each rotation factor becomes smaller, and a phase flip operation can be performed on the sequence under a finer bandwidth (that is, the sequence corresponding to the unit subchannel), thereby obtaining an LTF sequence with better PAPR performance. The embodiment of the present application is described by taking the bandwidth of the unit subchannel as 20MHz or 40MHz as an example. The rotation factor shown in the embodiment of the present application can be called a frequency domain rotation factor.

[0268] The sequence corresponding to the unit subchannel can be determined based on the basic LTF sequence and the bandwidth of the unit subchannel. As an example, the bandwidth of the unit subchannel is 40MHz, and there is c in the above sequence (1). 2i-1 =c 2i , i=1,2,…,16, there is c in the above sequence (2) 2i-1 =c 2i , i=1,2,…,12. The sequence corresponding to the unit subchannel can be {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500)}, {LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}. As another example, the bandwidth of the unit subchannel is 20 MHz, and the above sequence (1) may have c 2i-1 ≠c 2i , i=1,2,…,16, there can be c in the above sequence (2) 2i-1 ≠c 2i , i=1,2,…,12. The sequence corresponding to the unit subchannel can be {LTF 80MHz_2x(1:245)}, {LTF 80MHz_2x (246:500)}, {LTF 80MHz_2x (502:756)}, {LTF 80MHz_2x (757:1001)}.

[0269] Exemplarily, the LTF sequence can be determined based on the sequence corresponding to the unit subchannel and the rotation factor sequence. The rotation factor sequence can be a sequence of rotation factors, or a sequence composed of rotation factors. The sequence corresponding to each unit subchannel can correspond to a rotation factor, and the modulus value of the rotation factor can be 1. For example, the rotation factor can be 1 or -1. The length of the rotation factor sequence can be determined by the bandwidth of the PPDU and the bandwidth of the unit subchannel. If the bandwidth of the PPDU is represented by BW and the bandwidth of the unit subchannel is represented by BW_{element}, the length of the rotation factor sequence can be equal to BW / BW_{element}. The length of the rotation factor sequence is an integer.

[0270] Exemplarily, the LTF sequence can be obtained by periodically extending and phase-flipping the sequence corresponding to the unit subchannel in the frequency domain. The number of periodic extensions is equal to the length of the rotation factor sequence. For example, a 1 in the rotation factor sequence corresponds to no phase flipping of the sequence corresponding to the unit subchannel, and a -1 in the rotation factor sequence corresponds to a phase flipping of the sequence corresponding to the unit subchannel, such as a 180° phase flipping of the sequence corresponding to the unit subchannel. For another example, a j in the rotation factor sequence corresponds to a 90° phase rotation of the sequence corresponding to the unit subchannel, and a -j corresponds to a 270° phase rotation of the sequence corresponding to the unit subchannel.

[0271] The following example illustrates the relationship between a unit subchannel, a sequence corresponding to the unit subchannel, and a rotation factor sequence.

[0272] As an example, if the bandwidth of the PPDU is 640MHz and the bandwidth of the unit subchannel is 40MHz, the length of the rotation factor sequence is 640MHz / 40MHz=16, that is, the rotation factor sequence includes 16 rotation factors. When constructing the LTF sequence, the sequence corresponding to the unit subchannel can be periodically extended 16 times in sequence, and the rotation factors of the sequence corresponding to the unit subchannel can correspond to the elements in the rotation factor sequence in sequence. 80MHz_2x (1:245)} Extend once, the rotation factor is the first element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} is extended once, and the rotation factor is the second element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend once, the rotation factor is the third element in the rotation factor sequence; {LTF 80MHz_2x(757:1001)} is extended once, and the rotation factor is the fourth element in the rotation factor sequence; then, {LTF 80MHz_2x (1:245)} Extend the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the second time, the rotation factor is the sixth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend for the second time, the rotation factor is the seventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} is extended for the second time, and the rotation factor is the eighth element in the rotation factor sequence; then, {LTF 80MHz_2x (1:245)} Extend for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the third time, the rotation factor is the tenth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} The third extension is performed, and the rotation factor is the eleventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} Extend for the third time, the rotation factor is the twelfth element in the rotation factor sequence; {LTF 80MHz_2x (1:245)} Extend the fourth time, the rotation factor is the thirteenth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the fourth time, the rotation factor is the fourteenth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend for the fourth time, the rotation factor is the fifteenth element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} The fourth extension is performed, and the rotation factor is the sixteenth element in the rotation factor sequence. The total number of period extensions is 16. The LTF sequence can be referred to as sequence (3), sequence (5), and sequence (6) below.

[0273] As another example, the bandwidth of the PPDU is 640MHz, and the bandwidth of the unit subchannel is 20MHz. Then the length of the rotation factor sequence is 640MHz / 20MHz=32, that is, the rotation factor sequence includes 32 rotation factors. For example, for sequence (1), the c in sequence (1) is j is the rotation factor, j=1,2,…,32. For example, the sequence LTF corresponding to the unit subchannel 80MHz_2x The rotation factor of (1:245) is c1, and the sequence LTF corresponding to the unit subchannel 80MHz_2xThe rotation factor for (246:500) is c2, and so on. The sequences corresponding to the unit subchannels and the rotation factors can be found in the above examples and will not be detailed here. For LTF sequences, see Sequence (3), Sequence (4), and Sequence (6) below.

[0274] As another example, if the bandwidth of the PPDU is 480MHz and the bandwidth of the unit subchannel is 40MHz, the length of the rotation factor sequence is 480MHz / 40MHz=12, that is, the rotation factor sequence includes 12 rotation factors. When constructing the LTF sequence, the sequence corresponding to the unit subchannel can be periodically extended 12 times in sequence, and the rotation factors of the sequence corresponding to the unit subchannel can correspond to the elements in the rotation factor sequence in sequence. 80MHz_2x (1:245)} Extend once, the rotation factor is the first element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} is extended once, and the rotation factor is the second element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend once, the rotation factor is the third element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} is extended once, and the rotation factor is the fourth element in the rotation factor sequence; then, {LTF 80MHz_2x (1:245)} Extend the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the second time, the rotation factor is the sixth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend for the second time, the rotation factor is the seventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} is extended for the second time, and the rotation factor is the eighth element in the rotation factor sequence; then, {LTF 80MHz_2x (1:245)} Extend for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the third time, the rotation factor is the tenth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} The third extension is performed, and the rotation factor is the eleventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} The third extension is performed, and the rotation factor is the twelfth element in the rotation factor sequence. The total number of period extensions is 12. The LTF sequence can be referred to as sequence (7) below.

[0275] As another example, if the PPDU bandwidth is 480 MHz and the unit subchannel bandwidth is 20 MHz, the length of the rotation factor sequence is 480 MHz / 20 MHz = 24, that is, the rotation factor sequence includes 24 rotation factors. The sequence corresponding to the unit subchannel and the rotation factors can be referred to the above example and will not be described in detail here. The LTF sequence can refer to the sequence (8) below.

[0276] In this embodiment of the present application, the first communication device may store an LTF sequence. For example, the first communication device may store an LTF sequence and a base LTF sequence. For another example, the first communication device may store an LTF sequence, a base LTF sequence, and a rotation factor sequence, etc., which are not listed here. For more information about the LTF sequence, please refer to the following.

[0277] 302. The first communication device sends a PPDU, and correspondingly, the second communication device receives the PPDU.

[0278] 303. The second communication device performs channel estimation based on the LTF sequence.

[0279] Exemplarily, after receiving the PPDU, the second communication device may perform channel estimation based on the LTF sequence. Exemplarily, the second communication device may store the LTF sequence, and the second communication device may perform channel estimation under noise interference based on the received PPDU and its stored LTF sequence. The specific method of channel estimation is not limited in the embodiments of the present application.

[0280] The following describes in detail the LTF sequence involved in the embodiments of the present application.

[0281] Exemplarily, the LTF sequence may be any one of the following sequences (3) to (8).

[0282] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0283] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0284] -LTF 80MHz_2x(1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0285] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0286] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0287] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0288] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0289] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(3)

[0290] For sequence (3), the LTF sequence includes the following sequence (3a) or the following sequence (3b). That is, the LTF sequence can be the following sequence (3a) or sequence (3b):

[0291] LTF -4084,4084 =

[0292] {LTF 80MHz_2x(1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0293] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0294] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0295] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0296] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0297] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0298] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0299] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(3a)

[0300] LTF -4084,4084 =

[0301] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0302] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0303] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0304] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0305] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0306] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0307] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0308] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(3b)

[0309] For sequence (3), sequence (3a), and sequence (3b), LTF 80MHz_2x (1:245) represents the first to the 245th element in the basic LTF sequence. 80MHz_2x (246:500) represents the 246th to 500th elements in the basic LTF sequence. 80MHz_2x (502:756) represents the 502th to 756th elements in the basic LTF sequence. 80MHz_2x (757:1001) represents the 757th to 1001th elements in the basic LTF sequence. 80MHz_2x (a:b) represents the sequence LTF 80MHz_2x From the ath to the bth element in . 23 Indicates that 23 consecutive elements in the LTF sequence are 0. 23 For the relevant description of the basic LTF sequence, please refer to Figure 3 and will not be described in detail here. For the relevant description of the basic LTF sequence, please refer to the above and will not be described in detail here. The relevant description of sequence (3) here, such as sequence (3a), sequence (3b) and various parameters, is also applicable below.

[0310] For example, the above sequence (3a) can also be understood as the LTF sequence in 2x mode with a bandwidth of 640 MHz, where the values ​​of the subcarriers with index values ​​of -4080:4080 are:

[0311] 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-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,0,0,0,0,0,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0, -1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,0,0,0,0,0,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,-1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1, 0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1},

[0312] Each sequence shown below can be expanded in a similar manner to sequence (3a), and will not be described in detail below. When the basic LTF sequence changes, the expanded content of the LTF sequence also changes.

[0313] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0314] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0315] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0316] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),023 ,

[0317] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0325] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0326] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0327] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0328] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0329] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0330] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(4a)

[0331] LTF -4084,4084 =

[0332] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x(502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0333] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0334] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0335] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0336] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0337] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0338] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0339] -LTF 80MHz_2x (1:245),-LTF80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(4b)

[0340] For the relevant descriptions of sequence (4a), sequence (4b) and sequence (4), please refer to the description of sequence (3) above, which will not be described in detail here.

[0341] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0342] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0343] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0344] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0345] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0346] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x(502:756), LTF 80MHz_2x (757:1001), 0 23 ,

[0347] LTF 80MHz_2x (1:245), LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 ,

[0348] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, -LTF 80MHz_2x (502:756), -LTF 80MHz_2x (757:1001)}(5)

[0349] For sequence (5), the LTF sequence can include the following sequence (5a) or sequence (5b):

[0350] LTF -4084,4084 =

[0351] {LTF 80MHz_2x (1:245), LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 ,

[0352] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, -LTF 80MHz_2x (502:756), -LTF 80MHz_2x (757:1001), 0 23 ,

[0353] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, -LTF 80MHz_2x (502:756), -LTF 80MHz_2x (757:1001), 0 23 ,

[0354] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0355] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0356] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0357] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0358] <h2 style=";text-align:left;direction:ltr"> -LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001)}(5a)<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0359] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> -4084,4084 <h2 style=";text-align:left;direction:ltr"> =<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0360] <h2 style=";text-align:left;direction:ltr"> {-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),-LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0361] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (1:245),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (246:500),0,LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (502:756),LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x <h2 style=";text-align:left;direction:ltr"> (757:1001),0<h2 style=";text-align:left;direction:ltr"> 23 <h2 style=";text-align:left;direction:ltr"> ,<h2 style=";text-align:left;direction:ltr"> <h2 style=";text-align:left;direction:ltr">

[0362] <h2 style=";text-align:left;direction:ltr"> LTF<h2 style=";text-align:left;direction:ltr"> 80MHz_2x(1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0363] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0364] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0365] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0366] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0367] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(5b)

[0368] For the relevant descriptions of sequence (5a), sequence (5b) and sequence (5), please refer to the description of sequence (3) above, which will not be described in detail here.

[0369] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0370] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0371] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0372] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0373] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0374] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0375] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0376] LTF 80MHz_2x(1:245), LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001)}(6)

[0377] For sequence (6), the LTF sequence can include the following sequence (6a) or sequence (6b):

[0378] LTF -4084,4084 =

[0379] {-LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, -LTF 80MHz_2x (502:756), -LTF 80MHz_2x (757:1001), 0 23 ,

[0380] LTF 80MHz_2x (1:245), LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 [[ID=四十]],

[0381] LTF 80MHz_2x (1:245), LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 ,

[0382] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 , [[ID=六十八]]

[0383] -LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, LTF 80MHz_2x (502:756), LTF 80MHz_2x (757:1001), 0 23 ,

[0384] LTF 80MHz_2x (1:245), LTF 80MHz_2x It should be noted that there is an incorrect "四十" in the translation of line 39 which should be corrected to ", " as per the original text. Also, there is a misspelling in the translation of line 68 which should be corrected to "

[0383] ".(246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0385] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0386] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(6a)

[0387] LTF -4084,4084 =

[0388] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0389] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0390] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0391] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23,

[0392] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0393] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0394] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0395] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(6b)

[0396] For the relevant descriptions of sequence (6a), sequence (6b) and sequence (6), please refer to the description of sequence (3) above, which will not be described in detail here.

[0397] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0398] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0399] -LTF 80MHz_2x(1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0400] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0401] LTF<00​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0408] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0409] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0410] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(7a)

[0411] LTF -3060,3060 =

[0412] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0413] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0414] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),023 ,

[0415] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0416] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0417] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(7b)

[0418] For the relevant descriptions of sequence (7a), sequence (7b) and sequence (7), please refer to the description of sequence (3) above, which will not be described in detail here.

[0419] ±{-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0420] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0421] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0422] LTF80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0423] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0424] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(8)

[0425] For sequence (8), the LTF sequence can include the following sequence (8a) or sequence (8b):

[0426] LTF -3060,3060 =

[0427] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),-0 23 ,

[0428] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0429] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),-0 23 , s

[0430] LTF 80MHz_2x (1:245),-LTF80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0431] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0432] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(8a)

[0433] LTF -3060,3060 =

[0434] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0435] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0436] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0437] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),023 ,

[0438] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0439] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(8b)

[0440] For the relevant descriptions of sequence (8a), sequence (8b) and sequence (8), please refer to the description of sequence (3) above, which will not be described in detail here.

[0441] The LTF sequence shown in the embodiment of the present application fully considers the impact of MRU or RU on the sequence, as well as the impact of pilot rotation on the sequence. By considering different MRUs or RUs, and the differences in data subcarriers and pilot subcarriers caused by pilot rotation under each MRU, the LTF sequence can be applied to more types of MRUs or RUs, making the LTF sequence compatible with various RUs or MRUs. The following introduces MRU and pilot rotation respectively.

[0442] (1)MRU / RU

[0443] Exemplarily, the MRU of the PPDU includes an MRU of k×996+m×484 subcarriers, where k is an integer greater than or equal to 4, and m is equal to 0 or 1. The LTF sequence on the MRU may have different PAPR performance depending on the position and size of the MRU in the PPDU bandwidth. In addition, the trade-off between the signaling overhead for indicating the MRU and spectrum efficiency needs to be considered. Therefore, the embodiments of the present application comprehensively consider PAPR performance, signaling overhead, and spectrum efficiency, and provide two MRU modes (such as a first MRU mode and a second MRU mode), each of which includes multiple MRUs. Exemplarily, the first MRU mode can also be understood as a simple MRU, which has a small number of MRUs and therefore low signaling overhead. The second MRU mode can also be understood as a detailed MRU, which has a larger number of MRUs and higher spectrum utilization. Generally speaking, the SIG field in the PPDU can include information for indicating the MRU, so the MRU mode is related to the signaling of the SIG field in the PPDU. The name of the SIG field shown here is only an example. For example, the information used to indicate the MRU can also be carried in the UHR-SIG field or the next generation SIG field.

[0444] The LTF sequence constructed based on the first MRU mode and the second MRU mode is not limited to the MRU in the first MRU mode and the second MRU mode shown in the embodiments of the present application, and can also be used for other MRUs. That is, the LTF sequence shown in the embodiments of the present application can also well meet the needs of more MRUs. The MRU mode shown in the embodiments of the present application can also be called an MRU pattern, MRU style, or MRU type, etc.

[0445] The following describes the MRU involved in the PPDU shown in the embodiment of the present application.

[0446] As an example, when the PPDU bandwidth is 640 MHz, the MRU of the 640 MHz PPDU includes any of the following:

[0447] MRU of 7×996 subcarriers (also known as 7×996-tone MRU), MRU of 6×996 subcarriers (also known as 6×996-tone MRU), MRU of 5×996 subcarriers (also known as 5×996-tone MRU), MRU of 7×996+484 subcarriers (also known as 7×996+484-tone MRU), MRU of 6×996+484 subcarriers (also known as 6×996+484-tone MRU), MRU of 5×996+484 subcarriers (also known as 5×996+484-tone MRU), and MRU of 4×996+484 subcarriers (also known as 4×996+484-tone MRU).

[0448] For example, if 40 MHz subchannels are not punctured in 640 MHz, the MRU includes any of the following: an MRU of 7×996 subcarriers as shown in Figure 4a, an MRU of 6×996 subcarriers as shown in Figure 4b, or an MRU of 5×996 subcarriers as shown in Figure 4c. The MRUs shown in Figures 4a to 4c can be understood as MRUs in the first MRU mode corresponding to 640 MHz.

[0449] For example, if the punctured subchannels in 640 MHz include a 40 MHz subchannel, the MRU includes any of the following: an MRU of 7×996+484 subcarriers as shown in Figure 4d, an MRU of 6×996+484 subcarriers as shown in Figure 4e, an MRU of 5×996+484 subcarriers as shown in Figure 4f, or an MRU of 4×996+484 subcarriers as shown in Figure 4g. The MRUs shown in Figures 4d to 4g can be understood as MRUs in the second MRU mode corresponding to 640 MHz.

[0450] When the bandwidth of the PPDU is 640MHz, the effective bandwidth of the MRU shown in Figures 4a, 4b, 4d, and 4e is greater than or equal to 480MHz. The effective bandwidth is the remaining bandwidth in the 640MHz bandwidth excluding the perforated sub-channels. For example, when the bandwidth of the PPDU is 640MHz, the effective bandwidth of the MRU shown in Figures 4c, 4f, and 4g is less than or equal to 480MHz. Therefore, the MRU shown in Figures 4c, 4f, and 4g can also be reused for the MRU of the 480MHz PPDU. As a result, the types of MRUs of the PPDU can be effectively reduced, and the signaling overhead caused by indicating the MRU is reduced. For example, the MRU shown in Figures 4c, 4f, and 4g can also be called the MRU in the third MRU mode corresponding to 480MHz.

[0451] As another example, when the PPDU bandwidth is 480 MHz, the MRU for the 480 MHz PPDU includes: an MRU of 5×996+484 subcarriers as shown in Figure 5a , an MRU of 5×996 subcarriers as shown in Figure 5b , an MRU of 4×996+484 subcarriers as shown in Figure 5c , and an MRU of 4×996 subcarriers as shown in Figure 5d . The MRUs shown in Figures 5a to 5d can be referred to as MRUs in the fourth MRU mode corresponding to 480 MHz.

[0452] (2) Pilot rotation

[0453] Since the duration of the OFDM symbol of the 2xLTF sequence is longer than that of the OFDM symbol of the 1xLTF sequence, the phase noise is large. Therefore, pilot rotation is introduced for pilot correction, such as the P matrix (P as shown below). LTF) and the R matrix (shown as R below) LTF ). That is, the first communication device can generate a PPDU based on the LTF sequence and the P matrix and the R matrix.

[0454] The pilot rotation during LTF transmission corresponds to the spatial mapping matrix as shown below:

[0455] Among them, K pilot Indicates the index of the pilot subcarrier. LTF is a The matrix, Indicates the number of spatial streams corresponding to the LTF sequence.

[0456] For example, R LTF With P LTF The following relationship can be satisfied between them: LTF ] m,n =[P LTF ] m,1 ,1≤m,

[0457] Where m represents the mth row of the matrix, and n represents the nth column of the matrix.

[0458] For example, P LTF It can be as follows:

[0459] For example, when the number of spatial streams is 3 or 4, the first communication device may use the matrix P 4×4 Generate PPDU. When the number of spatial streams is 5 or 6, the first communication device can use the matrix P 6×6 Generate PPDU. When the number of spatial streams is 7 or 8, the first communication device can use the matrix P 8×8 Generate PPDU. For example, the above matrix P 4×4 , matrix P 6×6 , matrix P 8×8 They are as follows:

[0460] It can be understood that the matrix P shown above 4×4 , matrix P 6×6 , matrix P 8×8 This is merely an example. As standards evolve, the aforementioned matrices may also change, and this is not limited by the present embodiments. When the aforementioned matrices change, an LTF sequence can similarly be constructed based on the changed matrices and MRUs. In this case, the constructed LTF sequence also falls within the scope of protection of the present embodiments.

[0461] As an example, when the bandwidth of the PPDU is 640MHz, the LTF sequence can be any one of sequence (3) to sequence (6). Exemplarily, when the MRU mode of the 640MHz PPDU is the first MRU mode, the LTF sequence can be sequence (3) or sequence (4). Exemplarily, when the MRU mode of the 640MHz PPDU is the second MRU mode, the LTF sequence can be sequence (5) or sequence (1). Exemplarily, when the effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz, the LTF sequence can be sequence (6). The LTF sequence design takes into account different MRU designs, which can better guarantee PAPR performance and reduce PAPR values, thereby effectively reducing the requirements for linear power amplifier devices.

[0462] As another example, when the bandwidth of the PPDU is 480 MHz, the LTF sequence may be sequence (7) or sequence (8).

[0463] The MRU shown in the embodiments of this application is only an example. In actual applications, the MRU of a PPDU can be higher, and this embodiment of this application does not limit this. That is, when the PPDU bandwidth is 640 MHz or 480 MHz, both the first communication device and the second communication device can apply the LTF sequence provided in the embodiments of this application.

[0464] In the embodiment of the present application, when the bandwidth of the PPDU is greater than 320 MHz, an LTF sequence that can be carried in the LTF is provided, so that it can be effectively applied to the PPDU with a large bandwidth.

[0465] In view of the LTF sequence, PPDU bandwidth, MRU / RU, and pilot rotation shown in the embodiment of the present application, the method shown in FIG3 can also be understood as:

[0466] As an example, the first communication device maps a sequence segment in the LTF sequence corresponding to the RU / MRU position to a subcarrier in the RU / MRU based on the bandwidth, the size of the RU / MRU, and the RU / MRU position; wherein the RU / MRU is located within the above bandwidth, the RU / MRU includes multiple consecutive subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320 MHz is any one of sequences (3) to (8). The first communication device sends the above LTF sequence.

[0467] Correspondingly, the second communication device can receive the LTF sequence carried by the LTF in the PPDU; determine the LTF sequence corresponding to the RU / MRU based on the bandwidth, the size of the RU / MRU and the RU / MRU position, and the LTF sequence can be used to estimate the channel of the RU / MRU, wherein the RU / MRU is located within the bandwidth, the RU / MRU includes multiple continuous subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320MHz is any one of sequences (3) to (8).

[0468] As another example, the first communication device maps, based on the bandwidth, a sequence segment in the LTF sequence corresponding to a position of a subcarrier in a RU / MRU included in the bandwidth onto a subcarrier in the RU / MRU; wherein the RU / MRU is located within the bandwidth, the RU / MRU includes a plurality of consecutive subcarriers, and the LTF sequence in 2x mode when the bandwidth is greater than 320 MHz is any one of sequences (3) to (8). The first communication device transmits the LTF sequence.

[0469] Correspondingly, the second communication device can receive the LTF sequence carried by the LTF in the PPDU; determine the LTF sequence corresponding to the RU / MRU based on the bandwidth and the subcarrier position in the RU / subcarrier position in the MRU included in the bandwidth, and the LTF sequence can be used to estimate the channel of the RU / MRU, wherein the RU / MRU is located within the bandwidth, the RU / MRU includes multiple continuous subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320MHz is such as any one of sequences (3) to (8).

[0470] Exemplarily, the second communication device may estimate the channel of the RU / MRU based on the LTF sequence it receives and the LTF sequence it stores.

[0471] As another example, the first communication device maps the sequence segment corresponding to the RU / MRU position in the LTF sequence to the subcarrier in the RU / MRU based on the bandwidth, the matrix corresponding to the pilot rotation (such as the P matrix and the R matrix shown above), the size of the RU / MRU, and the RU / MRU position; wherein the RU / MRU is located within the above bandwidth, the RU / MRU includes multiple consecutive subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320MHz is any one of sequences (3) to (8). The first communication device sends the above LTF sequence.

[0472] Correspondingly, the second communication device can receive the LTF sequence carried by the LTF in the PPDU; determine the LTF sequence corresponding to the RU / MRU based on the bandwidth, the matrix corresponding to the pilot rotation (such as the P matrix and the R matrix shown above), the size of the RU / MRU and the RU / MRU position, and the LTF sequence can be used to estimate the channel of the RU / MRU, wherein the RU / MRU is located within the bandwidth, the RU / MRU includes multiple continuous subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320MHz is any one of sequences (3) to (8).

[0473] As another example, the first communication device maps a sequence segment in the LTF sequence corresponding to the position of the subcarrier in the RU / MRU included in the bandwidth onto the subcarrier in the RU / MRU according to the bandwidth and the matrix corresponding to the pilot rotation; wherein the RU / MRU is located within the above-mentioned bandwidth, the RU / MRU includes multiple consecutive subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320 MHz is any one of sequences (3) to (8). The first communication device transmits the above-mentioned LTF sequence.

[0474] Correspondingly, the second communication device can receive the LTF sequence carried by the LTF in the PPDU; according to the bandwidth, the matrix corresponding to the pilot rotation, and the subcarrier position in the RU / subcarrier position in the MRU included in the bandwidth, determine the LTF sequence corresponding to the RU / MRU, and the LTF sequence can be used to estimate the channel of the RU / MRU, wherein the RU / MRU is located within the bandwidth, the RU / MRU includes multiple continuous subcarriers, and the LTF sequence in the 2x mode when the bandwidth is greater than 320MHz is such as any one of sequences (3) to (8).

[0475] The bandwidth shown above may be the bandwidth of the PPDU, and the RU / MRU may be the RU / MRU of the PPDU.

[0476] For the specific content of the LTF sequence, please refer to the above, and for the construction method of the LTF sequence, please refer to the following, which will not be described in detail here.

[0477] The following describes the construction method of the LTF sequence provided in the embodiments of the present application.

[0478] The description of constructing the LTF sequence (or generating the LTF sequence) shown in the embodiment of the present application is only an example. In a specific implementation, each LTF sequence can be defined by a standard, etc. That is to say, the various steps in the construction method shown below are only examples. In a specific implementation, the communicating parties may not perform the various steps shown below, such as the communicating parties may save the LTF sequence. It can be understood that the construction method shown below is shown as an example when the bandwidth of the PPDU is 480MHz or 640MHz, but the embodiment of the present application is also applicable to the construction method of the LTF sequence when the bandwidth of the PPDU is greater than 640MHz. When the bandwidth of the PPDU is greater than 640MHz, or when the bandwidth of the PPDU is greater than other bandwidths of 320MHz except 480MHz and 640MHz (such as 540MHz, etc.), the LTF sequence constructed according to the construction method shown in the embodiment of the present application or the MRU shown above also falls within the protection scope of the embodiment of the present application.

[0479] The design of LTF needs to consider the PAPR corresponding to the sequence of the partial bandwidth used by all possible RUs and MRUs in the bandwidth. The construction of the LTF sequence may be related to at least one of the size, number, number of spatial streams, and puncturing position and size of the MRU of the PPDU. In view of the ultra-large bandwidth 640MHz PPDU and 480MHz PPDU that may appear in the next generation WLAN, the multiple RUs and MRUs that may appear in the two PPDUs and the RUs and MRUs existing in 802.11be are taken into consideration, and multiple pilot rotation methods are taken into consideration. With the minimization of the maximum PAPR of RU / MRU as the optimization goal, the LTF sequence is constructed, which effectively reduces the requirements for linear power amplifier devices. The LTF sequence shown in the embodiment of the present application can minimize the maximum PAPR of the sequences corresponding to all RUs or MRUs, or make the maximum PAPR of the sequences corresponding to all RUs or MRUs smaller. Exemplarily, the sequence corresponding to the minimum PAPR value is determined from the maximum PAPR values ​​of multiple sequences (also referred to as candidate LTF sequences) as the LTF sequence. This LTF sequence can better guarantee the PAPR performance of all RUs and MRUs, or can effectively ensure that the PAPR of each MRU within the bandwidth is as low as possible. Generally, there can be multiple MRUs within the bandwidth of the PPDU. Therefore, by ensuring that the PAPR performance of the MRU with the worst PAPR performance within the bandwidth is as good as possible, the determined LTF sequence can be compatible with more MRUs or RUs. In addition to considering different RUs or MRUs, the embodiments of the present application also consider sequences corresponding to different unit subchannels. For example, the smaller the bandwidth of the unit subchannel, the finer the rotation factor of the sequence corresponding to the unit subchannel, and thus the better the PAPR performance of the constructed LTF sequence.

[0480] The LTF sequence shown in the embodiment of the present application can be used for channel estimation of the next generation large bandwidth 640MHz PPDU and 480MHz PPDU.

[0481] Exemplarily, the process of constructing an LTF sequence may be as follows:

[0482] %Parameter initialization%

[0483] Set the PPDU bandwidth to BW = 480 or 640 MHz;

[0484] Set the unit subchannel bandwidth to BW_{element} = 20MHz, 40MHz (can also be set to 80MHz, 160MHz, etc.);

[0485] Calculate the number of subchannels as BW / BW_{element};

[0486] The frequency domain rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, resulting in a total of 2 (BW / BW_{element}) possible rotation factor sequences;

[0487] %2xLTF sequence calculation process%

[0488] Start loop

[0489] For each possible rotation factor sequence

[0490] For each RU / MRU

[0491] For each pilot rotation corresponding to the spatial stream

[0492] Calculate the PAPR of the 2xLTF sequence;

[0493] Calculate the maximum PAPR of all RU / MRU and all pilot rotation conditions in the rotation factor sequence;

[0494] End the loop

[0495] Find the minimum value of the maximum PAPR values ​​of all rotation factor sequences, and find the rotation factor sequence corresponding to the minimum value.

[0496] The construction process shown above is only an example. The following describes the construction method of the LTF sequence with reference to a specific example.

[0497] The first MRU mode based on the 640MHz PPDU can be understood as an MRU mode obtained by simply doubling the MRU in the 320MHz PPDU in the 802.11be standard. For relevant descriptions of the first MRU mode, please refer to the relevant descriptions of Figures 4a to 4c above, which will not be described in detail here. The following explanations are given using the bandwidth of the unit sub-channel as an example of 20MHz and 40MHz. The bandwidth of the unit sub-channel shown in the embodiment of the present application is only an example. In a specific implementation, unit sub-channels of other bandwidths may also be involved when constructing the LTF sequence.

[0498] Example 1, first MRU mode, the bandwidth of the unit subchannel is 40 MHz

[0499] 1A. When the PPDU bandwidth is BW = 640MHz and the unit subchannel bandwidth is BW_{element} = 40MHz, the number of sequences corresponding to the unit subchannel can be 640MHz / 40MHz = 16, that is, BW / BW_{element} = 16. The rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, that is: the rotation factor sequence LTF_{40MHzrotation} = {a1,…,a i ,…,a 16}, where any a i = ±1. At this time, a total of 2(BW / BW_{element}) = 65536 possible rotation factor sequences are obtained. For example, c 2i-1 =c 2i =a i , i=1,2,…,16. About c 2i-1 =c 2i For related explanations, please refer to the description of the unit subchannel in step 301 and will not be described in detail here. For the convenience of reference and brevity below, the embodiments of the present application use different representations (such as 1A to 1D, and 2A to 2D, etc.) to distinguish different steps or different descriptions. However, the distinction between different steps or different descriptions in the embodiments of the present application should not be understood as a limitation of the embodiments of the present application.

[0500] 1B. For any 2xLTF sequence, because OFDMA transmission and preamble puncturing may divide a 2xLTF sequence into multiple subsequences, each subsequence is transmitted on a different RU / MRU. In this case, only a portion of the sequence on each RU / MRU is used for actual wireless transmission. This allows the PAPR to be calculated for the subsequences occupied by different RUs / MRUs, effectively determining the LTF sequence. In the 640 MHz PPDU, this embodiment of the present application not only considers the MRU included in the first MRU mode in 640 MHz. In addition, the RU / MRU defined in 802.11be is also considered, such as 484+242-tone MRU, 996+484-tone MRU, 996+484+242-tone MRU, 2×996+484-tone MRU, 3×996-tone MRU and 3×996+484-tone MRU, and the RU defined in 802.11be is also considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU and 4×996-tone RU, etc. Since the length of the OFDM symbol occupied by the LTF used to carry the 2xLTF sequence is longer than the length of the OFDM symbol occupied by 1xLTF, it is easily affected by non-ideal channels, so the pilot is required for phase calibration. The different spatial stream matrices of the pilot subcarrier and the data subcarrier have a certain impact on the PAPR performance. Therefore, the embodiment of the present application also considers the matrix P shown above for each candidate LTF sequence. 4×4 , matrix P 6×6 , matrix P 8×8 The corresponding pilot rotation.

[0501] 1C. For each candidate 2xLTF sequence, the PAPR is calculated respectively by considering pilot rotations corresponding to various numbers of spatial streams and various MRU / RU patterns.

[0502] PAPR can satisfy the following formula:

[0503] The above formula can also be expressed as: PAPR = max(abs(ifft(LTF,N)).^2) / mean(abs(ifft(LTF,N)).^2). For example, IFFT(LTF,N) represents the calculation result of the N-point inverse fast Fourier transform of the sequence, and the value of N can be upsampled by four times the number of IFFT points required for the sequence. abs() represents the absolute value of the sequence, x.^2 represents the square calculation of each element of the sequence, and mean() represents the average value of the sequence. For example, the value of N can be 8*1024*4, where 4 represents the number of samples. To facilitate the digital-to-analog conversion process, the value of N can be multiplied by 4 (for example only). 1024 represents the number of subcarriers of an 80MHz PPDU. Since the bandwidth of the PPDU shown in the embodiment of the present application is 640MHz, the value of N needs to be multiplied by 8.

[0504] 1D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs of all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{40MHzrotation} corresponding to this minimum value is ±{1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,1,-1}, as shown below:

[0505] {-1,1,1,1,1,-1,1,1,-1,-1,-1,-1,-1,-1,-1}; or,

[0506] {1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,1,1,-1,1}.

[0507] Exemplarily, for {-1,1,1,1,1,-1,1,1,1,-1,-1,-1,-1,-1,-1,-1}, the sequence corresponding to the unit subchannel can be periodically extended 16 times.

[0508] {LTF 80MHz_2x (1:245)} is extended once, and the rotation factor is the first element -1 in the rotation factor sequence. The sequence corresponding to the first unit subchannel in the LTF sequence and the sequence determined by the rotation factor is -{LTF 80MHz_2x (1:245)};{LTF 80MHz_2x (246:500)} is extended once, the rotation factor is the second element 1 in the rotation factor sequence, and the sequence corresponding to the second unit subchannel in the LTF sequence and the sequence determined by the rotation factor is {LTF80MHz_2x (246:500)};{LTF 80MHz_2x (502:756)} is extended once, the rotation factor is the third element 1 in the rotation factor sequence, and the sequence corresponding to the third unit subchannel in the LTF sequence and the sequence determined by the rotation factor is {LTF 80MHz_2x (502:756)};{LTF 80MHz_2x (757:1001)} is extended once, the rotation factor is the fourth element 1 in the rotation factor sequence, and the sequence corresponding to the fourth unit subchannel in the LTF sequence and the sequence determined by the rotation factor is {LTF 80MHz_2x (757:1001)}; and so on, such as {LTF 80MHz_2x (1:245)} Extend the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the second time, the rotation factor is the sixth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend for the second time, the rotation factor is the seventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} Extend for the second time, the rotation factor is the eighth element in the rotation factor sequence; {LTF 80MHz_2x (1:245)} Extend for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the third time, the rotation factor is the tenth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} The third extension is performed, and the rotation factor is the eleventh element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} Extend for the third time, the rotation factor is the twelfth element in the rotation factor sequence; {LTF 80MHz_2x (1:245)} Extend the fourth time, the rotation factor is the thirteenth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} Extend for the fourth time, the rotation factor is the fourteenth element in the rotation factor sequence; {LTF 80MHz_2x (502:756)} Extend for the fourth time, the rotation factor is the fifteenth element in the rotation factor sequence; {LTF 80MHz_2x (757:1001)} is extended for the fourth time, and the rotation factor is the sixteenth element in the rotation factor sequence. The LTF sequence shown in the above sequence (3b) can be obtained by the above method.

[0509] The two rotation factor sequences are opposite to each other. The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0510] 80MHz subchannel: 9.6367dB;

[0511] 160MHz subchannel: 10.4040dB;

[0512] 320MHz subchannel: 10.8630dB;

[0513] 640MHz subchannel: 10.8988dB

[0514] For example, the above-mentioned 80MHz sub-channel considers RUs or MRUs with a bandwidth less than or equal to 80MHz, such as 996-tone RU and 484+242-tone MRU. The 160MHz sub-channel considers RUs or MRUs with a bandwidth greater than 80MHz and less than or equal to 160MHz, such as 2*996-tone RU, 996+484-tone MRU, and 996+484+242-tone MRU. The 320MHz sub-channel considers RUs or MRUs with a bandwidth greater than 160MHz and less than or equal to 320MHz, such as 4*996-tone RU, 3*996+484-tone MRU, 3*996-tone MRU, and 2*996+484-tone MRU. The 640MHz sub-channel considers RU / MRUs with a bandwidth greater than 320MHz and less than or equal to 640MHz, which includes the RU or MRU in the first MRU mode in the embodiment of the present application.

[0515] The MRU / RU included in the subsequent 80MHz sub-channel, 160MHz sub-channel, 320MHz sub-channel, 640MHz sub-channel, and 480MHz sub-channel are not described in detail. For example, the 480MHz sub-channel shown below considers the RU / MRU with a bandwidth greater than 320MHz and less than or equal to 480MHz, and is not described in detail below.

[0516] The specific content of the LTF sequence based on the first MRU mode and the 40MHz sub-channel rotation factor can refer to the above sequence (3).

[0517] Example 2, first MRU mode, unit subchannel is 20MHz

[0518] 2A. When the PPDU bandwidth is BW = 640 MHz and the unit subchannel bandwidth is BW_{element} = 20 MHz, the number of sequences corresponding to the unit subchannel is BW / BW_{element} = 32. The rotation factor sequence values ​​corresponding to each unit subchannel can be either all 1 or all -1, i.e., LTF_{20MHzrotation} = {a1,…,a i ,…,a 32}, where any a i = ±1. For example, there is any c i =a i , i = 1, 2, ..., 32. At this time, a total of 2 (BW / BW_{element}) = 4295000000 possible rotation factor sequences are obtained, which is about 4.29 billion in number, with extremely high computational complexity. Considering that there may be multiple MRU / RUs for each sequence, and each MRU / RU may have multiple pilot rotation methods, the actual computational complexity is much higher than the computer capability. Based on the local symmetry shown in the embodiment of the present application, the complexity can be effectively reduced, and a small number of candidate LTF sequences can be selected from the candidate sequences based on local symmetry.

[0519] Based on local symmetry, the rotation factor sequence shown in the embodiment of the present application satisfies at least one of the following:

[0520] First, the values ​​of the first group of elements in the rotation factor sequence are the same as the values ​​of the second group of elements. The second group of elements is symmetric with respect to the center of the rotation factor sequence. The first group of elements includes the (2*i-1)th element and the (2*i)th element, where i is greater than 0 and less than or equal to 1 / 2 times the length of the rotation factor sequence (i.e., less than or equal to BW / (2*BW_{element})). The local symmetry shown here can be local positive symmetry, which means that the values ​​of any (2*i-1)th and (2*i)th elements in the rotation factor sequence are the same as the two elements at their respective positions in the sequence. For example, BW = 640 MHz, BW_{element} = 20 MHz, and i is less than or equal to 16. If i = 1, the first set of elements consists of the first and second elements in the rotation factor sequence. The second set of elements, symmetrically positioned with respect to the first set, can consist of the last and second-to-last elements in the rotation factor sequence, i.e., the 32nd and 31st elements. Alternatively, if i = 2, the first set of elements consists of the third and fourth elements in the rotation factor sequence, and the second set of elements consists of the 30th and 29th elements. This continues in a similar fashion and is not listed here.

[0521] Second, the values ​​of the third group of elements in the rotation factor sequence are opposite to the values ​​of the fourth group of elements. The third group of elements is symmetric with respect to the center of the rotation factor sequence. The third group of elements includes the (2*j-1)th element and the (2*j)th element, where j is less than or equal to 1 / 2 times the length of the rotation factor sequence, and i is not equal to j. The local symmetry shown here can be local negative symmetry, which means that the values ​​of any (2*j-1)th element and the (2*j)th element in the rotation factor sequence are opposite to the values ​​of the two elements at their symmetric positions in the sequence. i is not equal to j. For example, BW = 640 MHz, BW_{element} = 20 MHz, and j is less than or equal to 16. If i = 1, then j is not equal to 1. For example, if j = 3, then the first group of elements can be the 5th and 6th elements in the rotation factor sequence, and the second group of elements can be the 28th and 27th elements in the rotation factor sequence. The value of the 5th element is the inverse of the value of the 28th element, and the value of the 6th element is the inverse of the value of the 27th element. And so on, which is not listed here one by one.

[0522] For example, based on the above local symmetry, all possible values ​​of two adjacent elements in any group of the rotation factor sequence and two elements in symmetric positions are shown in Table 1:

[0523] Table 1

[0524] The bandwidth length of each sequence in Table 1 is 20*4=80MHz, and there are 8 possible values ​​for this bandwidth. Therefore, there may be 8 (640 / 80) =16,777,216, or approximately 16.8 million, a significant decrease from the original 4.29 billion. This is because the PAPR value of the corresponding LTF sequence remains unchanged after the LTF sequence is inverted. Therefore, the number of candidate LTF sequences is further halved.

[0525] The local symmetry shown in the embodiments of the present application is applicable not only to the second embodiment, but also to other embodiments, such as the first embodiment, the third embodiment to the eighth embodiment, etc.

[0526] 2B. For instructions on step 2B, please refer to step 1B and will not be described in detail here.

[0527] 2C. For instructions on step 2C, please refer to step 1C and will not be described in detail here.

[0528] 2D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs of all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{20MHzrotation} corresponding to this minimum is ±{1,1,1,1,-1,-1,1,1,1,-1,-1,1,-1,1,-1,1,-1,-1,1,-1,-1,1,-1,-1,-1,1,-1,-1,1,1,1,1}, as shown below:

[0529] {1,1,1,1,-1,-1,1,1,1,-1,-1,1,-1,1,-1,1,-1,1,-1,-1,1,-1,-1,-1,-1,1,1,1,1,1}; or,

[0530] {-1,-1,-1,-1,1,1,-1,-1,-1,-1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1};

[0531] The two rotation factor sequences are inverse numbers of each other. The maximum PAPR of each sub-channel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0532] 80MHz subchannel: 9.6367dB;

[0533] 160MHz subchannel: 10.4040dB;

[0534] 320MHz subchannel: 10.6326dB;

[0535] 640MHz subchannel: 10.8305dB

[0536] The specific content of the LTF sequence based on the first MRU mode and the 20MHz sub-channel rotation factor can refer to the above sequence (4).

[0537] The second MRU mode based on the 640MHz PPDU is a more detailed MRU constructed while retaining 484-tone puncturing. The following examples illustrate this using 40MHz and 20MHz unit subchannel bandwidths. For details about the second MRU mode, refer to Figures 4d through 4g above and will not be further elaborated here.

[0538] Example 3, second MRU mode, unit subchannel is 40MHz

[0539] 3A. For the detailed description of step 3A, please refer to step 1A and will not be described in detail here.

[0540] 3B. In the 640 MHz PPDU, the MRU included in the second MRU mode in 640 MHz is considered. In addition, the RU / MRU defined in 802.11be is also considered, such as 484+242-tone MRU, 996+484-tone MRU, 996+484+242-tone MRU, 2×996+484-tone MRU, 3×996-tone MRU, and 3×996+484-tone MRU. The RU defined in 802.11be is also considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU, and 4×996-tone RU.

[0541] For other instructions on step 3B, please refer to step 1B and will not be described in detail here.

[0542] 3C. For instructions on step 3C, please refer to step 1C and will not be described in detail here.

[0543] 3D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs of all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{40MHzrotation} corresponding to this minimum value is ±{1,1,-1,-1,-1,-1,-1,-1,1,1,-1,1,1,-1,-1}, as shown below:

[0544] {1,1,-1,-1,-1,-1,-1,1,-1,1,1,1,-1,-1}; or,

[0545] {-1,-1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,1,1}.

[0546] The two rotation factor sequences are opposite to each other. The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0547] 80MHz subchannel: 9.6367dB;

[0548] 160MHz subchannel: 10.9316dB;

[0549] 320MHz subchannel: 10.7971dB;

[0550] 640MHz subchannel: 11.0946dB

[0551] The specific content of the LTF sequence based on the second MRU mode and the 40MHz sub-channel rotation factor can refer to the above sequence (5).

[0552] Example 4, second MRU mode, unit sub-channel is 20MHz

[0553] 4A. For instructions on step 4A, please refer to step 2A and will not be described in detail here.

[0554] The relevant description about local symmetry in step 4A can also refer to the relevant description in 2A or Table 1, etc., which will not be described in detail here.

[0555] 4B. For the relevant instructions on step 4B, please refer to step 3B and will not be described in detail here.

[0556] 4C. For instructions on step 4C, please refer to step 3C or step 1C, which will not be described in detail here.

[0557] 4D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs for all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{20MHzrotation} corresponding to this minimum is ±{1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,-1,-1,-1,1,1,1,1,1,-1,-1,-1,-1}, as shown below:

[0558] {1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,-1,-1,-1,-1,1,1,1,1,1,1,-1,-1,-1,-1}; or,

[0559] {-1,-1,-1,-1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1};

[0560] The two rotation factor sequences are inverse numbers of each other. The maximum PAPR of each sub-channel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0561] 80MHz subchannel: 9.6367dB;

[0562] 160MHz subchannel: 10.9316dB;

[0563] 320MHz subchannel: 10.7971dB;

[0564] 640MHz subchannel: 11.0946dB

[0565] The specific content of the LTF sequence based on the second MRU mode and the 20MHz sub-channel rotation factor can refer to the above sequence (1).

[0566] The effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz, such as the outermost 160MHz subchannel in the MRU of the 640MHz PPDU. Therefore, the above sequence (6) can also be applied to the PPDU when the effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz. For the relevant description of the MRU when the effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz, please refer to the relevant description of {6×996-tone MRU 1 and 6×996-tone MRU 4} in Figures 4c, 4f, 4g and 4b above, which will not be described in detail here. The fifth and sixth embodiments shown below can be understood as the construction method of the LTF sequence when the effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz. Since the effective bandwidth is less than or equal to 480MHz, the fifth and sixth embodiments shown below can be applied to both the construction method of the LTF of the 640MHz PPDU and the construction method of the LTF sequence of the 480MHz PPDU. The fifth and sixth embodiments shown below may be ways of constructing LTF sequences in the third MRU mode of a 480MHz PPDU. The first to fourth embodiments described above may be ways of constructing LTF sequences when the effective bandwidth of a 640MHz PPDU is greater than or equal to 480MHz.

[0567] The third MRU pattern (MRU pattern 3) reuses {6×996-tone MRU 1 and 6×996-tone MRU 4 (as shown in Figure 4b), 5×996+484-tone MRU (as shown in Figure 4f), 5×996-tone MRU (as shown in Figure 4c), and 4×996+484-tone MRU (as shown in Figure 4g)} in the 640 MHz PPDU. The 5×996+484-tone MRU (as shown in Figure 4f), 5×996-tone MRU (as shown in Figure 4c), 4×996+484-tone MRU (as shown in Figure 4g), 6×996-tone MRU 1 (as shown in Figure 4b), and 6×996-tone MRU 4 (as shown in Figure 4b) in MRU pattern 3 in the 640 MHz PPDU have an effective transmission bandwidth less than or equal to 480 MHz due to puncturing the outermost 160 MHz channels. Therefore, these MRUs can be used to transmit 480 MHz PPDUs. Since the above effective bandwidth is greater than the maximum PPDU bandwidth of 320 MHz in the 802.11be standard, it is also necessary to be compatible with the RU / MRU in the 802.11be standard.

[0568] In the design of the 2xLTF sequence for the 480MHz PPDU based on MRU pattern 3, the embodiment of the present application constructs the 2xLTF sequence based on the 20MHz unit subchannel and the 40MHz unit subchannel respectively. Since the MRU pattern 3 reuses part of the MRU in the 640MHz, the expression of the LTF sequence constructed in the embodiment of the present application can be the same as the above sequence (1).

[0569] Example 5, third MRU mode, unit subchannel is 40MHz

[0570] 5A. MRU pattern 3 reuses some MRUs in the 640MHz PPDU. Therefore, the PPDU bandwidth BW = 640MHz. When the unit subchannel bandwidth is BW_{element} = 40MHz, the number of sequences corresponding to the unit subchannel is BW / BW_{element} = 16. The rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, that is, LTF_{40MHzrotation} = {a1,…,a i ,…,a 16}, where any a i = ± 1. At this time, a total of 2 (BW / BW_{element}) = 65536 possible rotation factor sequences are obtained.

[0571] For the relevant instructions on step 5A, please refer to step 1A, etc., and will not be described in detail here.

[0572] 5B. In the 640 MHz PPDU, the MRU included in the third MRU mode in 640 MHz is considered. In addition, the RU / MRU defined in 802.11be are also considered, such as 484+242-tone MRU, 996+484-tone MRU, 996+484+242-tone MRU, 2×996+484-tone MRU, 3×996-tone MRU, and 3×996+484-tone MRU. The RU defined in 802.11be are also considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU, and 4×996-tone RU.

[0573] For relevant instructions on pilot rotation, P matrix and R matrix, etc., please refer to step 1B, etc., and will not be described in detail here.

[0574] 5C. For the relevant instructions on step 5C, please refer to step 1C, etc., which will not be described in detail here.

[0575] 5D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs of all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{40MHzrotation} corresponding to this minimum value is ±{-1,-1,1,1,1,1,-1,1,-1,1,1,1,1,-1,-1}, as shown below:

[0576] {1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1}; or,

[0577] {-1,-1,1,1,1,1,-1,1,-1,1,1,1,1,1,-1,-1}.

[0578] The two rotation factor sequences are opposite to each other. The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0579] 80MHz subchannel: 9.6367dB;

[0580] 160MHz subchannel: 10.9316dB;

[0581] 320MHz subchannel: 10.2876dB;

[0582] 640MHz subchannel: 10.9297dB

[0583] The specific content of the LTF sequence based on the third MRU mode and the 40MHz sub-channel rotation factor can refer to the above sequence (6).

[0584] Example 6, third MRU mode, unit sub-channel is 20MHz

[0585] 6A. MRU pattern 3 reuses some MRUs in the 640 MHz PPDU. Therefore, the bandwidth of the PPDU is BW=640 MHz. When the unit subchannel bandwidth is BW_{element}=20 MHz, the number of unit subchannels is BW / BW_{element}=32.

[0586] For relevant descriptions of step 6A, please refer to step 2A, such as the relevant descriptions of local symmetry, positive local symmetry, negative local symmetry and Table 1 in step 2A, which will not be described in detail here.

[0587] 6B. For the relevant instructions on step 6B, please refer to step 5B or 1B, etc., which will not be described in detail here.

[0588] 6C. For the relevant instructions on step 6C, please refer to step 1C, etc., which will not be described in detail here.

[0589] 6D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs for all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{20MHzrotation} corresponding to this minimum is ± {1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1}, as shown below:

[0590] {1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1}; or,

[0591] {-1,-1,-1,-1,1,1,1,1,1,1,1,-1,-1,-1,1,1,-1,-1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,-1}

[0592] The two rotation factor sequences are inverse numbers of each other. The maximum PAPR of each sub-channel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0593] 80MHz subchannel: 9.6367dB;

[0594] 160MHz subchannel: 10.9316dB;

[0595] 320MHz subchannel: 10.2876dB;

[0596] 640MHz subchannel: 10.9297dB

[0597] The specific content of the LTF sequence based on the third MRU mode and the 20MHz sub-channel rotation factor can refer to the above sequence (6).

[0598] For the MRU based on 480MHz PPDU, please refer to the relevant descriptions of Figures 5a to 5d, which will not be described in detail here. Embodiments 7 and 8 shown below are constructed based on the MRU of 480MHz PPDU, or based on the fourth MRU mode of 480MHz PPDU. Fourth MRU mode: {5×996+484-tone MRU (as shown in Figure 5a), 5×996-tone MRU (as shown in Figure 5b), 4×996+484-tone MRU (as shown in Figure 5c), 4×996-tone MRU (as shown in Figure 5d)}. The construction methods shown in Embodiments 7 and 8 can be applied to 480MHz PPDU.

[0599] Example 7, fourth MRU mode, unit subchannel is 40MHz

[0600] 7A. When the PPDU bandwidth is BW = 480 MHz and the unit subchannel bandwidth is BW_{element} = 40 MHz, the number of unit subchannels is BW / BW_{element} = 12. The frequency domain rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, that is, LTF_{40MHzrotation} = {a1,…,a i ,…,a 12}, where any a i = ±1. At this time, a total of 2(BW / BW_{element}) = 4096 possible rotation factor sequences are obtained. For example, c 2i-1=c 2i =a i , i=1,2,…,12.

[0601] For other instructions on step 7A, please refer to step 1A, etc., which will not be described in detail here.

[0602] 7B. In the 480 MHz PPDU, this embodiment of the present application considers MRU pattern 4 based on the 480 MHz PPDU. In addition, RU / MRU defined in 802.11be are also considered, such as 484+242-tone MRU, 996+484-tone MRU, 996+484+242-tone MRU, 2×996+484-tone MRU, 3×996-tone MRU, and 3×996+484-tone MRU. RU defined in 802.11be are also considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU, and 4×996-tone RU.

[0603] For other instructions on step 7B, please refer to step 6B or 1B, etc., which will not be described in detail here.

[0604] 7C. For relevant instructions on step 7C, please refer to step 6C or 1C, etc., and will not be described in detail here.

[0605] 7D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs of all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{40MHzrotation} corresponding to this minimum value is ±{1,-1,1,1,-1,-1,-1,-1,-1,1,1,-1}, as shown below:

[0606] {1,-1,1,1,-1,-1,-1,-1,1,1,1,-1}; or,

[0607] {-1,1,-1,-1,1,1,1,-1,-1,-1,-1}.

[0608] The two rotation factor sequences are opposite to each other. The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0609] 80MHz subchannel: 9.6367dB;

[0610] 160MHz subchannel: 10.3499dB;

[0611] 320MHz subchannel: 10.2876dB;

[0612] 480MHz subchannel: 10.8107dB

[0613] The specific content of the LTF sequence based on the third MRU mode and the 40MHz sub-channel rotation factor can refer to the above sequence (7).

[0614] Example 8, fourth MRU mode, unit subchannel is 20MHz

[0615] 8A. The bandwidth of PPDU is BW = 480MHz, the unit subchannel bandwidth is BW_{element} = 20MHz, and the number of sequences corresponding to the unit subchannel is BW / BW_{element} = 24. The rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, that is, LTF_{20MHzrotation} = {a1,…,a i ,…,a 24}, where any a i = ±1. At this point, a total of 2(BW / BW_{element}) = 16777216 possible rotation factor sequences are obtained, which is about 16.78 million. For example, c i =a i , i=1,2,…,24.

[0616] 8B. For the relevant instructions on step 8B, please refer to step 7B and will not be described in detail here.

[0617] 8C. For the relevant instructions on step 8C, please refer to step 7C, etc., which will not be described in detail here.

[0618] 8D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the spatial mapping matrices and the PAPRs for all RU / MRU patterns, and select the maximum PAPR_{max,i}. Among all PAPR_{max,i}, calculate the minimum {PAPR_{max,i}}_{min}. The rotation factor sequence LTF_{20MHzrotation} corresponding to this minimum is ±{-1,-1,1,1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,-1}, as shown below:

[0619] {-1,-1,1,1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,1,-1}; or,

[0620] {1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,-1,-1,-1,1,1,-1,-1,1}.

[0621] The two rotation factor sequences are opposite to each other. The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0622] 80MHz subchannel: 9.6367dB;

[0623] 160MHz subchannel: 10.4040dB;

[0624] 320MHz subchannel: 10.4665dB;

[0625] 480MHz subchannel: 10.5380dB

[0626] The specific content of the LTF sequence based on the fourth MRU mode and the 20MHz sub-channel rotation factor can refer to the above sequence (8).

[0627] The above-mentioned method of using local symmetry to reduce complexity and select a small number of candidate LTF sequences from candidate sequences is only an example. For example, the following method can also be used to reduce complexity.

[0628] For example, when the frequency domain sequence is even symmetric, its time domain signal contains only the real part, and this real part signal is the same as the real part of the time domain signal corresponding to the half-sequence of the frequency domain signal (such as the partial sequence in the frequency domain sequence). When the frequency domain sequence is odd symmetric, its time domain signal contains only the imaginary part, and this imaginary part signal is the same as the imaginary part of the time domain signal corresponding to the half-sequence of the frequency domain sequence. Therefore, when the odd-symmetric sequence and the even-symmetric sequence are superimposed, the time domain signal corresponding to the combined sequence is similar to the time domain signals corresponding to the two half-sequences, and has a lower PAPR.

[0629] Therefore, when the rotation factor sequence also satisfies the above relationship as shown in the frequency domain sequence, a lower PAPR can also be achieved. 4i+1 ,c 4i+2 ,c 4i+3 ,c 4i+4 ]=±[-cN+1-(4i+1),cN+1-(4i+2),-cN+1-(4i+3),cN+1-(4i+4)].

[0630] Wherein, N represents the length of the rotation factor sequence, and i is an integer greater than or equal to 0 and less than N / 4-1.

[0631] Based on the above approach, illustratively, the sequences and corresponding PAPRs of the 20 MHz sub-channel rotations in the first MRU mode, the second MRU mode, and the third MRU mode are as follows:

[0632] For the first MRU mode, if the bandwidth of the unit subchannel is 20 MHz, the rotation factor sequence can be: ±{1,1,1,1,-1,-1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,-1}.

[0633] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0634] 80MHz subchannel: 9.6367dB;

[0635] 160MHz subchannel: 10.6559dB;

[0636] 320MHz subchannel: 10.9196dB;

[0637] 640MHz subchannel: 10.9602dB

[0638] For the second MRU mode, if the bandwidth of the unit subchannel is 20 MHz, the rotation factor sequence can be: ±{-1,1,-1,1,1,1,1,-1,-1,-1,-1,-1,-1,1,1,1,1,-1,1,1,1,-1,1,1,1,-1,-1,-1,-1,-1,-1}.

[0639] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0640] 80MHz subchannel: 10.5309dB;

[0641] 160MHz subchannel: 11.0047dB;

[0642] 320MHz subchannel: 10.4322dB;

[0643] 640MHz subchannel: 11.1040dB

[0644] For the third MRU mode, if the bandwidth of the unit subchannel is 20 MHz, the rotation factor sequence can be: ±{1,-1,1,-1,-1,-1,-1,-1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1}.

[0645] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0646] 80MHz subchannel: 10.5309dB;

[0647] 160MHz subchannel: 11.0047dB;

[0648] 320MHz subchannel: 10.4322dB;

[0649] 640MHz subchannel: 10.9325dB

[0650] The specific content of the LTF sequence corresponding to the rotation factor sequence shown above is not shown one by one in the embodiment of this application. The specific content of the LTF sequence can be expanded according to the methods of the above embodiments 1 to 8, and will not be described in detail here.

[0651] It will be understood that the LTF sequence construction method shown above is based on an example of a PPDU bandwidth of 480 MHz or 640 MHz. In a specific implementation, the PPDU bandwidth may be larger. When the PPDU bandwidth is greater than 640 MHz, the LTF sequence can also be determined according to the above construction method. Alternatively, other LTF sequences not shown can also be determined according to the above construction method when the PPDU bandwidth is 480 MHz or 640 MHz. Therefore, any LTF sequence obtained according to the above construction method falls within the scope of protection of the embodiments of this application.

[0652] The following describes a communication device according to an embodiment of the present application.

[0653] The present application divides the functional modules of the communication device according to the above-mentioned method embodiment. For example, each functional module can be divided according to each function, or two or more functions can be integrated into one processing module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of modules in this application is schematic and is only a logical functional division. There may be other division methods in actual implementation. The communication device of the embodiment of the present application will be described in detail below with reference to Figures 6 to 8.

[0654] Figure 6 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application. As shown in Figure 6, the communication device includes a processing module 601 and a transceiver module 602. The transceiver module 602 can implement corresponding communication functions, and the processing module 601 is used to process data. For example, the transceiver module 602 can also be referred to as a communication interface or a communication module.

[0655] In some embodiments of the present application, the communication device can be used to execute the actions performed by the first communication device in the above method embodiment. In this case, the communication device can be a WLAN device or a chip or functional module configured in the WLAN device, etc. The transceiver module 602 is used to execute the transceiver-related operations of the first communication device in the above method embodiment, and the processing module 601 is used to execute the processing-related operations of the first communication device in the above method embodiment.

[0656] Exemplarily, the processing module 601 is used to generate a PPDU; the transceiver module 602 is used to send or output the PPDU.

[0657] It is understood that the transceiver module 602 can send the PPDU to other communication devices, or the transceiver module 602 can output the PPDU from the processing module 601 to other components or other functional modules in the first communication device. The relevant description of other information output by the transceiver module is similar and will not be detailed below.

[0658] In other embodiments of the present application, the communication device can be used to execute the actions performed by the second communication device in the above method embodiment. In this case, the communication device can be a WLAN device or a chip or functional module configured in the WLAN device, etc. The transceiver module 602 is used to execute the transceiver-related operations of the second communication device in the above method embodiment, and the processing module 601 is used to execute the processing-related operations of the second communication device in the above method embodiment.

[0659] The transceiver module 602 is used to receive or input PPDU; the processing module 601 is used to perform channel estimation based on the LTF sequence.

[0660] Optionally, the communication device may further include a storage module that can be used to store instructions and / or data. The processing module 601 can read the instructions and / or data in the storage module to enable the communication device to implement the aforementioned method embodiment. Exemplarily, the storage module can be used to store information such as LTF sequences.

[0661] It can be understood that the specific description of the transceiver module and the processing module shown in the embodiment of the present application is only an example. For the specific functions or execution steps of the transceiver module and the processing module, please refer to the above-mentioned method embodiment and will not be described in detail here.

[0662] In the above embodiments, the description of PPDU, LTF sequence, etc. can also be referred to the introduction in the above method embodiment, which will not be described in detail here.

[0663] The above describes the communication device according to the embodiment of the present application. The following describes possible product forms of the communication device. It should be understood that any product having the functions of the communication device described in FIG. 6 falls within the scope of protection of the embodiment of the present application. It should also be understood that the following description is merely illustrative and does not limit the product forms of the communication device according to the embodiment of the present application to these examples.

[0664] In one possible implementation, in the communication device shown in FIG6 , the processing module 601 may be one or more processors, the transceiver module 602 may be a transceiver, or the transceiver module 602 may be a transmitting module and a receiving module, the transmitting module may be a transmitter, the receiving module may be a receiver, and the transmitting module and the receiving module are integrated into a single device, such as a transceiver. In the embodiment of the present application, the processor and the transceiver may be coupled, etc., and the embodiment of the present application does not limit the connection method between the processor and the transceiver. During the execution of the above method, the process of sending information in the above method can be understood as the process of the processor outputting the above information. When outputting the above information, the processor outputs the above information to the transceiver so that the transceiver can transmit it. After being output by the processor, the above information may also need to undergo other processing before reaching the transceiver. Similarly, the process of receiving information in the above method can be understood as the process of the processor receiving the input information. When the processor receives the input information, the transceiver receives the above information and inputs it into the processor. Furthermore, after the transceiver receives the above information, the above information may need to be processed further before being received by the processor.

[0665] As shown in FIG. 7 a , the communication device 70 includes one or more processors 720 and a transceiver 710 .

[0666] In some embodiments of the present application, the communication device may be used to execute the steps or functions performed by the first communication device in the above method embodiments.

[0667] Exemplarily, the processor 720 is configured to generate a PPDU; and the transceiver 710 is configured to send the PPDU.

[0668] In other embodiments of the present application, the communication device may be used to execute the steps or functions performed by the second communication device in the above method embodiments.

[0669] The transceiver 710 is configured to receive a PPDU; and the processor 720 is configured to perform channel estimation based on an LTF sequence.

[0670] It will be understood that the specific descriptions of the transceiver and processor shown in the embodiments of the present application are merely examples. For the specific functions or execution steps of the transceiver and processor, reference may be made to the above-mentioned method embodiments, which will not be described in detail here.

[0671] In the above embodiments, the description of PPDU, LTF sequence, etc. can also be referred to the introduction in the above method embodiment, which will not be described in detail here.

[0672] In various implementations of the communication device shown in FIG7a , the transceiver may include a receiver and a transmitter, wherein the receiver is configured to perform a receiving function (or operation) and the transmitter is configured to perform a transmitting function (or operation). The transceiver is configured to communicate with other devices / apparatuses via a transmission medium.

[0673] Optionally, the communication device 70 may further include one or more memories 730 for storing program instructions and / or data, etc. The memory 730 is coupled to the processor 720. The coupling in the embodiment of the present application is an indirect coupling or communication connection between devices, units or modules, which can be electrical, mechanical or other forms, and is used for information exchange between devices, units or modules. The processor 720 may operate in conjunction with the memory 730. The processor 720 may execute program instructions stored in the memory 730. Optionally, at least one of the above-mentioned one or more memories may be included in the processor. Exemplarily, the memory can be used to store LTF sequences, etc.

[0674] The specific connection medium between the transceiver 710, processor 720, and memory 730 is not limited in the embodiments of the present application. In FIG7 a , the memory 730, processor 720, and transceiver 710 are connected via a bus 740. The bus is represented by a bold line in FIG7 a . The connection methods between other components are merely illustrative and are not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, and so on. For ease of illustration, FIG7 a uses only one bold line, but this does not mean that there is only one bus or only one type of bus.

[0675] In the embodiments of the present application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc., and may implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in the embodiments of the present application may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor, etc.

[0676] In the embodiment of the present application, the memory may include, but is not limited to, non-volatile memories such as a hard disk drive (HDD) or a solid-state drive (SSD), random access memory (RAM), erasable programmable read-only memory (EPROM), read-only memory (ROM) or portable read-only memory (CD-ROM), etc. The memory is any storage medium that can be used to carry or store program code in the form of instructions or data structures and can be read and / or written by a computer (such as the communication device shown in the present application), but is not limited thereto. The memory in the embodiment of the present application can also be a circuit or any other device that can realize a storage function, for storing program instructions and / or data.

[0677] Illustratively, the processor 720 is primarily used to process communication protocols and communication data, control the entire communication device, execute software programs, and process software program data. The memory 730 is primarily used to store software programs and data. The transceiver 710 may include a control circuit and an antenna. The control circuit is primarily used to convert baseband signals into radio frequency signals and process radio frequency signals. The antenna is primarily used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input / output devices, such as a touch screen, display, and keyboard, are primarily used to receive user input and output data to the user.

[0678] When the communication device is powered on, the processor 720 can read the software program in the memory 730, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 720 performs baseband processing on the data to be sent and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal to the outside in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 720. The processor 720 converts the baseband signal into data and processes the data.

[0679] In another implementation, the RF circuit and antenna may be provided independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be remotely arranged independent of the communication device.

[0680] It is understood that the communication device shown in the embodiment of the present application may also have more components than those in Figure 7a, and the embodiment of the present application is not limited to this. The method performed by the processor and transceiver shown above is only an example. For the specific steps performed by the processor and transceiver, please refer to the method described above.

[0681] Figure 7b is a schematic diagram of the structure of another communication device provided in an embodiment of the present application. As shown in Figure 7b, the communication device may include at least one of the following: a processor, a memory, a transmitter, a receiver, a signal detector, a digital signal processor, and a display screen (for displaying a user interface). For relevant descriptions of the processor, memory, transmitter, receiver, and display screen, please refer to Figure 7a and will not be described in detail here. The signal detector can be used to detect signals, such as detecting reference signals or demodulation signals. The digital signal processor can be used to process data input or output by the communication device. The description of the signal detector and the digital signal processor is not limited in the embodiment of the present application.

[0682] In another possible implementation, in the communication device shown in FIG6 , the processing module 601 may be one or more logic circuits, and the transceiver module 602 may be an input / output interface, or may be called a communication interface, or an interface circuit, or an interface, etc. Alternatively, the transceiver module 602 may be a sending module and a receiving module, the sending module may be an output interface, the receiving module may be an input interface, and the sending module and the receiving module may be integrated into one module, such as an input / output interface. As shown in FIG8 , the communication device shown in FIG8 includes a logic circuit 801 and an interface 802. That is, the processing module 601 may be implemented using a logic circuit 801, and the transceiver module 602 may be implemented using an interface 802. The logic circuit 801 may be a chip, a processing circuit, an integrated circuit, or a system-on-chip (SoC) chip, etc., and the interface 802 may be a communication interface, an input / output interface, a pin, etc. For example, FIG8 is illustrated using the communication device as a chip, and the chip includes a logic circuit 801 and an interface 802.

[0683] In the embodiment of the present application, the logic circuit and the interface may also be coupled to each other. The embodiment of the present application does not limit the specific connection method between the logic circuit and the interface.

[0684] In some embodiments of the present application, the communication device may be used to execute the steps or functions performed by the first communication device in the above method embodiments.

[0685] Illustratively, the logic circuit 801 is used to generate a PPDU; and the interface 802 is used to output the PPDU.

[0686] In other embodiments of the present application, the communication device may be used to execute the steps or functions performed by the second communication device in the above method embodiments.

[0687] The interface 802 is used to input the PPDU; the logic circuit 801 is used to perform channel estimation based on the LTF sequence.

[0688] It can be understood that the specific description of the logic circuit and interface shown in the embodiments of the present application is only an example. For the specific functions or execution steps of the logic circuit and interface, please refer to the above-mentioned method embodiment and will not be described in detail here.

[0689] Exemplarily, the chip may further include a memory, which may be used to store the LTF sequence.

[0690] In the above embodiments, the description of PPDU, LTF sequence frame, etc. can also refer to the introduction in the above method embodiment, which will not be described in detail here.

[0691] It can be understood that the communication device shown in the embodiment of the present application can implement the method provided in the embodiment of the present application in the form of hardware, or can implement the method provided in the embodiment of the present application in the form of software, etc., and the embodiment of the present application is not limited to this.

[0692] An embodiment of the present application further provides a communication system, which includes a first communication device and a second communication device. For descriptions of the first communication device and the second communication device, reference can be made to the above.

[0693] In addition, the present application also provides a computer program, which is used to implement the operations and / or processing performed by the first communication device in the method provided by the present application.

[0694] The present application also provides a computer program, which is used to implement the operations and / or processing performed by the second communication device in the method provided by the present application.

[0695] The present application also provides a computer-readable storage medium, which stores computer code. When the computer code runs on a computer, the computer executes the operations and / or processing performed by the first communication device in the method provided by the present application.

[0696] The present application also provides a computer-readable storage medium having computer code stored therein. When the computer code is run on a computer, the computer executes the operations and / or processing performed by the second communication device in the method provided in the present application.

[0697] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program is run on a computer, the operations and / or processing performed by the first communication device in the method provided by the present application are executed.

[0698] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program is run on a computer, the operations and / or processing performed by the second communication device in the method provided by the present application are executed.

[0699] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the modules can be a logical function division. In actual implementation, there can be other division methods, such as multiple modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or modules, or can be electrical, mechanical or other forms of connection.

[0700] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the technical effects of the solutions provided in the embodiments of the present application.

[0701] In addition, the functional modules in the various embodiments of the present application may be integrated into a module processing module, or each module may exist physically separately, or two or more modules may be integrated into a module. The above-mentioned integrated modules may be implemented in the form of hardware or software functional modules.

[0702] If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a readable storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned readable storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0703] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: The method comprises: Generate a physical layer protocol data unit PPDU, the PPDU including a long training field LTF carrying an LTF sequence, the length of the LTF sequence corresponds to the bandwidth of the PPDU, the LTF sequence is determined based on a basic LTF sequence corresponding to a basic subchannel, the bandwidth of the PPDU is greater than 320 MHz, and the LTF sequence is a 2x mode sequence; The PPDU is sent.

2. A communication method, characterized in that: The method comprises: Receive a physical layer protocol data unit PPDU, the PPDU including a long training field LTF carrying an LTF sequence, the length of the LTF sequence corresponds to the bandwidth of the PPDU, the LTF sequence is determined based on a basic LTF sequence corresponding to a basic subchannel, and the bandwidth of the PPDU is greater than 320 MHz; the LTF sequence is a 2x mode sequence; Channel estimation is performed based on the LTF sequence.

3. The method according to claim 1 or 2, characterized in that: The LTF sequence is determined based on a sequence corresponding to the unit sub-channel, and the sequence corresponding to the unit sub-channel is determined based on the basic LTF sequence.

4. The method according to claim 3, characterized in that The modulus value of the rotation factor of the sequence corresponding to the unit sub-channel is 1, and the bandwidth of the unit sub-channel is any one of the following: 20 MHz, 40 MHz.

5. The method according to claim 3 or 4, characterized in that: The LTF sequence is determined based on a sequence corresponding to the unit subchannel and a rotation factor sequence, and the rotation factor sequence is a sequence composed of rotation factors.

6. The method according to claim 4 or 5, characterized in that: The modulus value of the rotation factor of the sequence corresponding to the unit sub-channel is 1 includes: the rotation factor of the sequence corresponding to the unit sub-channel is 1 or -1.

7. The method according to claim 6, characterized in that The LTF sequence is obtained based on the period extension and phase flipping of the sequence corresponding to the unit subchannel in the frequency domain; The number of times the cycle is extended is equal to the length of the rotation factor sequence, 1 in the rotation factor sequence corresponds to not performing a phase flip on the sequence corresponding to the unit subchannel, and -1 in the rotation factor sequence corresponds to performing a phase flip on the sequence corresponding to the unit subchannel.

8. The method according to any one of claims 5 to 7, characterized in that: The length of the rotation factor sequence is determined by the bandwidth of the PPDU and the bandwidth of the unit subchannel.

9. The method according to any one of claims 5 to 8, characterized in that: The rotation factor sequence satisfies at least one of the following: The values ​​of the first group of elements in the rotation factor sequence are the same as the values ​​of the second group of elements, the second group of elements are elements whose positions are symmetrical to those of the first group of elements with the center position of the rotation factor sequence as the symmetry axis, the first group of elements includes the (2*i-1)th element and the (2*i)th element, where i is less than or equal to 1 / 2 times the length of the rotation factor sequence; The values ​​of the third group of elements in the rotation factor sequence are opposite to the values ​​of the fourth group of elements. The third group of elements is an element whose position is symmetrical to the fourth group of elements with the center position of the rotation factor sequence as the symmetry axis. The third group of elements includes the (2*j-1)th element and the (2*j)th element, j is less than or equal to 1 / 2 times the length of the rotation factor sequence, and i is not equal to j.

10. The method according to any one of claims 1 to 9, characterized in that: The bandwidth of the PPDU is 640 MHz, and the LTF sequence includes any of the following: ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}; ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 , LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}; ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}; ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}; Among them, LTF 80MHz_2x (1:245) indicates the sequence LTF 80MHz_2x The first to the 245th element in LTF 80MHz_2x (246:500) represents the sequence LTF 80MHz_2x The 246th to 500th elements in LTF 80MHz_2x (502:756) indicates the sequence LTF 80MHz_2x The 502nd to 756th elements in LTF 80MHz_2x (757:1001) indicates the sequence LTF 80MHz_2x The 757th to 1001th elements in the sequence LTF 80MHz_2x is the basic LTF sequence of the 2x mode, 0 23 It indicates that 23 consecutive elements in the LTF sequence are 0.

11. The method according to any one of claims 1 to 9, characterized in that: The bandwidth of the PPDU is 480 MHz, and the LTF sequence includes any of the following: ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}; ±{-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,-LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}; Among them, LTF 80MHz_2x (1:245) indicates the sequence LTF 80MHz_2x The first to the 245th element in LTF 80MHz_2x (246:500) represents the sequence LTF 80MHz_2x The 246th to 500th elements in LTF 80MHz_2x (502:756) indicates the sequence LTF 80MHz_2x The 502nd to 756th elements in LTF 80MHz_2x (757:1001) indicates the sequence LTF 80MHz_2x The 757th to 1001th elements in the sequence LTF 80MHz_2x is the basic LTF sequence of the 2x mode, 0 23 It indicates that 23 consecutive elements in the LTF sequence are 0.

12. A communication device, characterized in that: The method comprises a module for executing the method according to any one of claims 1 to 11.

13. A communication device, characterized in that: The method comprises a processor configured to execute the method according to any one of claims 1 to 11.

14. A communication device, characterized in that: comprising a logic circuit and an interface, wherein the logic circuit and the interface are coupled; The interface is used to input and / or output information, and the logic circuit is used to execute the method according to any one of claims 1-11.

15. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program. When the computer program is executed, the method according to any one of claims 1 to 11 is executed.

16. A communication method, characterized in that: The method comprises the method according to any one of claims 1 to 11.

17. A communication system, characterized in that: The method comprises a first communication device and a second communication device, wherein the first communication device is used to execute the method according to any one of claims 1 and 3-11, and the second communication device is used to execute the method according to any one of claims 2-11.

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