Communication method and device

Abstract

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

Description

Technical Field

[0001] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0002] In recent years, wireless traffic has grown at an ultra-high speed, and users have increasingly higher demands for communication service quality, such as low latency and ultra-reliability. As a key technology for carrying wireless traffic services, wireless local area network (WLAN) continues to develop and evolve to meet users' increasingly high requirements for wireless transmission. In order to improve the throughput of next-generation wireless LAN systems, a major challenge of 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) can provide a means for the receiver to estimate the multi-input multi-output (MIMO) channel in the WLAN system.

[0003] 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.

[0004] Therefore, how to design LTF sequences for the next generation WLAN system is an important task. Summary of the invention

[0005] An embodiment of the present application provides a communication method and apparatus, and 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 channel estimation.

[0006] In a first aspect, an embodiment of the present application provides a communication method, which may be applied to a first communication device, which may be a Wi-Fi device or applied to a Wi-Fi chip or module, and the method includes:

[0007] Generate a physical layer protocol data unit PPDU, the PPDU includes 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; send the PPDU.

[0008] 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 of signal estimation.

[0009] In a second aspect, an embodiment of the present application provides a communication method, which can be applied to a second communication device, where the second communication device can be a Wi-Fi device or applied to a Wi-Fi chip or module, and the method includes:

[0010] A physical layer protocol data unit PPDU is received, wherein the PPDU includes a long training field LTF carrying an LTF sequence, wherein 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.

[0011] 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.

[0012] 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.

[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 a rotation factor sequence, and the rotation factor sequence is a sequence composed of rotation factors.

[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, including: the rotation factor of the sequence corresponding to the unit subchannel is 1 or -1.

[0015] In combination with the first aspect or the second aspect, in a possible implementation method, 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 a phase flipping of the sequence corresponding to the unit subchannel.

[0016] 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.

[0017] In combination with the first aspect or the second aspect, in a possible implementation manner, the rotation factor sequence satisfies at least one of the following:

[0018] 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;

[0019] 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.

[0020] In combination with the first aspect or the second aspect, in a possible implementation manner, the bandwidth of the PPDU is 640 MHz, and the LTF sequence includes any of the following:

[0021] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0022] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),023 ,

[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)};

[0029] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF80MHz_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),0 23 ,

[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)};

[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),0 23 ,

[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)};

[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),0 23 ,

[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)};

[0053] 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.

[0054] In combination with the first aspect or the second aspect, in a possible implementation manner, the bandwidth of the PPDU is 480 MHz, and the LTF sequence includes any of the following:

[0055] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23,

[0056] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[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)};

[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),0 23 ,

[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)};

[0067] 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.

[0068] In a third aspect, an embodiment of the present application provides a communication method, which can be applied to a first communication device, where the first communication device can be a Wi-Fi device or applied to a Wi-Fi chip or module, and the method includes:

[0069] 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 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.

[0070] or,

[0071] 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 a plurality of continuous subcarriers.

[0072] In combination with the third aspect, in a possible implementation manner, when the bandwidth is greater than 320 MHz, the LTF sequence in the 2x mode is any one of the following:

[0073] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0074] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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,LTF 80MHz_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)};

[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),0 23 ,

[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)};

[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),0 23 ,

[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,-LTF80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)};

[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),0 23 ,

[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),-LTF80MHz_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)};

[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),0 23 ,

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

[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),0 23 ,

[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)};

[0117] 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.

[0118] In combination with the third aspect, in a possible implementation manner, mapping a sequence segment corresponding to the RU position / the MRU position in the LTF sequence on a subcarrier in the RU / the MRU according to the bandwidth, the size of the resource unit (resource unit, RU) / multiple resource units (multiple resource units, MRU), and the RU / MRU position includes:

[0119] 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 in the LTF sequence corresponding to the RU position / the MRU position is mapped onto the subcarriers in the RU / the MRU.

[0120] The LTF sequence provided in the embodiment of the present application takes into account both the various 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.

[0121] In combination with the third aspect, in a possible implementation manner, mapping, according to the bandwidth, a sequence segment in the LTF sequence corresponding to a subcarrier position in the RU / a subcarrier position in the MRU included in the bandwidth onto a subcarrier in the RU / the MRU includes:

[0122] 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.

[0123] In a fourth aspect, an embodiment of the present application provides a communication method, which may be applied to a second communication device, where the second communication device may be a Wi-Fi device or applied to a Wi-Fi chip or module, and the method includes:

[0124] Receive an LTF sequence; determine an LTF sequence corresponding to the RU / MRU according to the bandwidth, the size of the RU / MRU and the position of the RU / MRU, wherein the LTF sequence is used to estimate the channel of the RU / MRU, wherein the RU / MRU is located within the bandwidth and the RU / MRU includes multiple continuous subcarriers.

[0125] or,

[0126] 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 continuous subcarriers.

[0127] When the bandwidth is greater than 320 MHz, the LTF sequence in the 2x mode is as shown in the third aspect.

[0128] 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.

[0129] 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

[0130] In a fifth aspect, an embodiment of the present application provides a first communication device, configured to execute 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.

[0131] In a sixth aspect, an embodiment of the present application provides a second communication device, configured to execute 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.

[0132] In a seventh aspect, an embodiment of the present application provides a first communication device, the first communication device comprising a processor, configured to execute the method described in the first aspect or 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 or the third aspect or any possible implementation is executed.

[0133] In a possible implementation manner, the memory is located outside the first communication device.

[0134] In a possible implementation manner, the memory is located in the first communication device.

[0135] 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 first communication device may be a chip.

[0136] In a possible implementation manner, the first communication device further includes a transceiver, and the transceiver is used to receive information or send information.

[0137] In an eighth aspect, an embodiment of the present application provides a second communication device, the second communication device comprising a processor, configured to execute the method described in the second aspect or 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 or the fourth aspect or any possible implementation is executed.

[0138] In a possible implementation manner, the memory is located outside the second communication device.

[0139] In a possible implementation manner, the memory is located in the second communication device.

[0140] 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.

[0141] In a possible implementation manner, the second communication device further includes a transceiver, and the transceiver is used to receive information or send information.

[0142] 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.

[0143] In a possible implementation, the interface being used to output information includes: the interface being used to output PPDU. Exemplarily, the logic circuit is used to generate PPDU.

[0144] 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.

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

[0146] 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, the second aspect, the third aspect, the fourth aspect or any possible implementation method is executed.

[0147] In the twelfth aspect, an embodiment of the present application provides a computer program product, which includes a computer program or a computer code. When the computer program product runs on a computer, the method shown in the first aspect, the second aspect, the third aspect, the fourth aspect or any possible implementation method is executed.

[0148] 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 first aspect, the second aspect, the third aspect, the fourth aspect or any possible implementation is executed.

[0149] 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.

[0150] 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.

[0151] 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

[0152] Figure 1It is a schematic diagram of the architecture of a communication system provided by an embodiment of the present application;

[0153] Figure 2a It is a schematic diagram of the format of a PPDU provided in an embodiment of the present application;

[0154] Figure 2b It is a schematic diagram of the format of a PPDU provided in an embodiment of the present application;

[0155] Figure 3 It is a flow chart of a communication method provided in an embodiment of the present application;

[0156] Figure 4a to Figure 4g is a schematic diagram of an MRU provided in an embodiment of the present application;

[0157] Figure 5a to Figure 5d is a schematic diagram of an MRU provided in an embodiment of the present application;

[0158] Figure 6 is a structural diagram of a communication device provided in an embodiment of the present application;

[0159] Figure 7a and Figure 7b is a structural diagram of a communication device provided in an embodiment of the present application;

[0160] Figure 8 It is a structural diagram of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0161] To facilitate understanding of the technical solution of the present application, the present application will be further described below in conjunction with the accompanying drawings.

[0162] The terms "first" and "second" in the specification, claims and drawings of this application are only used to distinguish different objects, rather than 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 these processes, methods, products or devices.

[0163] The "embodiment" mentioned in this article means that the specific features, structures or characteristics described in conjunction with the embodiment can 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 is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It can be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0164] In the present 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 may 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 may exist, such as only A exists, only B exists; when A and B are not mutually exclusive, it can also mean that there are three relationships, such as only A exists, only B exists, and A and B exist at the same time. The character " / " generally indicates that the associated objects before and after 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".

[0165] The embodiment of the present application provides a communication method and device, and 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 of signal estimation. The LTF sequence can be effectively applied to the situation where the bandwidth of the PPDU is greater than 320MHz. 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. 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.

[0166] The following introduces the communication system involved in the embodiments of the present application.

[0167] The technical solution provided in the embodiment of the present application can be applied to WLAN systems, such as Wi-Fi, etc. The method provided in the embodiment of the present application can be applied to the IEEE 802.11 series of protocols, such as 802.11a / b / g protocol, 802.11n protocol, 802.11ac protocol, 802.11ax protocol, 802.11be protocol, 802.11bn protocol or the next generation of protocols, etc., which are not listed one by one. The technical solution provided in the embodiment of the present application can also be applied to wireless personal area networks (WPANs) based on millimeter wave (MMW) and ultra wideband (UWB) technologies. The method provided in the embodiment of the present application can be applied to the IEEE802.15 series of protocols, such as 802.15.4a protocol, 802.15.4z protocol or 802.15.4ab protocol, or a future generation of UWB WPAN protocols, etc., which are not listed one by one. The technical solution 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), 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.

[0168] WLAN systems can provide high-speed and low-latency transmission. With the continuous evolution of WLAN application scenarios, WLAN systems will be applied to more scenarios or industries, such as the Internet of Things industry, the Internet of Vehicles industry or 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 sites) can be sensor nodes in smart cities (such as smart water meters, smart electricity meters, smart air detection nodes), smart devices in smart homes (such as smart cameras, projectors, display screens, televisions, 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 in the Internet of Vehicles, infrastructure in daily life scenarios (such as vending machines, self-service navigation desks in supermarkets, self-service cash registers, self-service ordering machines, etc.), and equipment in large sports and music venues.

[0169] 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 IEEE802.11 standard, mainly used in Europe) and wide area network (WAN) or other networks now known or developed later.

[0170] In a 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).

[0171] An access point is a device with wireless communication function, supports communication or perception using WLAN protocol, has the function of communicating or perceiving with other devices in the WLAN network (such as non-AP STA or other access points), and of course, can also have the function of communicating or perceiving with other devices. Alternatively, an access point is equivalent to a bridge connecting a wired network and a wireless network, and its main function is to connect various wireless network clients together, and then connect the wireless network to the Ethernet. In a WLAN system, an access point can be called an access point station (AP STA). The device with wireless communication function can be a complete device, or a chip, a processing system or a functional module installed in the complete device, and the device installed with these chips or processing systems or functional modules can implement the method and function of the embodiment of the present application under the control of the chip or processing system or functional module. The AP in the embodiment of the present application is a device that provides services for non-AP STA, and can support 802.11 series 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, which is mainly deployed in homes, buildings and parks, with a typical coverage radius of tens of meters to hundreds of meters. Of course, it can also be deployed outdoors. For another example, the AP may be a communication entity such as a communication server, a router, a switch, a bridge, etc.; the AP may include various forms of macro base stations, micro base stations, relay stations, etc. Of course, the AP may also be a chip or a processing system or module in the above-mentioned various forms of equipment, so as to realize the method and function of the embodiment of the present application.

[0172] STA is a device with wireless communication function, supports communication or perception using WLAN protocol, and has the ability to communicate or perceive with other non-AP STA or access points in the WLAN network. In the WLAN system, the station can be called a non-access point station (non-AP STA). For example, STA is any user communication device that allows the user to communicate or perceive with the AP and then communicate with the WLAN. The device with wireless communication function can be a complete device, or a chip or processing system or functional module installed in the complete device. The device installed with these chips or processing systems or functional modules can implement the methods and functions of the embodiments of the present application under the control of the chip or processing system or functional module. For example, STA can be a wireless communication chip, a wireless sensor or a wireless communication terminal, etc., and can also be called a user. For another example, STA can be a mobile phone supporting Wi-Fi communication function, a tablet supporting Wi-Fi communication function, a set-top box supporting Wi-Fi communication function, a smart TV supporting Wi-Fi communication function, a smart wearable device supporting Wi-Fi communication function, a vehicle-mounted communication device supporting Wi-Fi communication function, and a computer supporting Wi-Fi communication function. Of course, STA can also be a chip or processing system or module in the above-mentioned various forms of devices, so as to implement the methods and functions of the embodiments of the present application.

[0173] Exemplarily, the communication system to which the method provided in the embodiment of the present application can be applied may include access points and stations. For example, the embodiment of the present application may be applicable to the scenario of communication or perception between AP and STA, between AP and AP, or between STA and STA in WLAN, and the embodiment of the present application is not limited to this. Optionally, the AP may communicate or perceive with a single STA, or the AP may communicate or perceive with multiple STAs at the same time. Specifically, the communication or perception between the AP and multiple STAs can be divided into downlink transmission in which the AP sends signals to multiple STAs at the same time, and uplink transmission in which multiple STAs send signals to the AP. Among them, the WLAN communication protocol can be supported between the AP and the STA, between the AP and the AP, and between the STA and the STA. The communication protocol may include the IEEE802.11 series of protocols, such as 802.11n / 802.11ac / 802.11ax / 802.11be / 802.11bn protocols, and of course, it is also applicable to protocols after 802.11bn.

[0174] Figure 1 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 1An access point such as AP1 and three stations such as STA1, STA2 and STA3 are shown in FIG. Figure 1 The communication between AP1 and STA1 shown in FIG. 1 , or the communication between AP1 and STA1, STA2), or the communication between AP and AP (such as Figure 1 ), or, for communication between STAs (such as Figure 1 The method provided in the embodiment of the present application may be applicable to, but not limited to, uplink / downlink transmission of a single user, uplink / downlink transmission of multiple users, vehicle-to-everything (V2X, X can represent anything), 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.

[0175] Understandable, Figure 1 The STA is a mobile phone and the AP is a router as an example, which does not limit the types of AP and STA in the embodiments of the present application. Figure 1 Only one AP and three STAs are shown for example, but the number of the APs or STAs may be more or less, which is not limited in the embodiments of the present application.

[0176] From the different perspectives of sending PPDU and receiving PPDU, the first communication device shown below can be understood as a communication device that sends PPDU, and the second communication device can be understood as a communication device that receives PPDU. As an example, the first communication device and the second communication device can be Wi-Fi chips or modules or processing systems set in different Wi-Fi devices. As another example, the first communication device can be an AP, and the second communication device can be an 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 (multi-link device, MLD), etc., and the embodiments of the present application are no longer listed one by one. Exemplarily, a multi-link device (multi-link device, MLD) means that the device has multiple sites (such as AP or non-APSTA) at the same time, respectively working on different frequency bands or channels. The multi-link device includes multiple subordinate sites, and the subordinate sites can be physical sites or logical sites. Each site can work on a link or 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 a wireless communication function. The communication device may be a complete device, or may be a chip or a processing system or a module installed in the complete device. Devices installed with these chips or processing systems or modules may implement the methods and functions of the embodiments of the present application under the control of these chips or processing systems or modules. A multi-link device may implement wireless communication in accordance with the 802.11 series of protocols, thereby achieving 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, sub1GHz, 2.4GHz, 5GHz, 6GHz, etc., which are not listed one by one here.

[0177] 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.

[0178] The following introduces the communication method provided by the embodiments of the present application.

[0179] To meet the requirements of higher throughput, larger coverage, etc., the IEEE 802.11be standard defines two PPDU formats: very high throughput multi-user physical layer protocol data unit (EHT multi-user PHY protocol data unit, EHT MU PPDU) and very high throughput trigger-based physical layer protocol data unit (EHT trigger-based PPDU, EHT TB PPDU). For example, Figure 2a This is a schematic diagram of the structure of EHT MU PPDU. Figure 2b This is a schematic diagram of the structure of EHT TB PPDU.

[0180] like Figure 2a As shown, 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), etc. Figure 2b As shown, the EHT TB PPDU includes L-STF, L-LTF, L-SIG field, RL-SIG field, U-SIG field, EHT-STF, EHT-LTF, data field and PE, etc. Among them, EHT-LTF can be used for channel estimation at the receiving end (i.e., the communication device receiving the PPDU). Figure 2a and Figure 2b The time length shown is the duration of the field, or the length of the orthogonal frequency division multiplexing (OFDM) symbol corresponding to the field. Figure 2a or Figure 2b Each field shown may occupy one or more OFDM symbols, and one OFDM symbol may occupy 4 microseconds (us). The duration occupied by one OFDM symbol shown here is only an example and should not be understood as a limitation on the embodiments of the present application.

[0181] 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 described above. Figure 2a and Figure 2bAs shown, 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.

[0182] Exemplarily, the EHT-LTF modes can be divided into three types, namely: 1xLTF, 2xLTF, and 4xLTF, wherein 1xLTF represents an LTF sequence in 1x mode; 2xLTF represents an LTF sequence in 2x mode; and 4xLTF represents an LTF sequence in 4x mode.

[0183] 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, a 2x EHT-LTF sequence (as shown below) -2036,2036 ) can be as follows:

[0184] EHTLTF -2036,2036 =

[0185] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0186] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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)}

[0189] Among them, 0 23 Indicates that 23 consecutive values ​​are 0, or that 23 consecutive elements in the EHT-LTF sequence are all 0. LTF 80MHz_2x (a:b) indicates the sequence LTF 80MHz_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.

[0190] For example, the basic LTF sequence corresponding to the basic subchannel (ie, LTF 80MHz_2x ) can be as follows:

[0191] LTF 80MHz_2x =

[0192] {+1,0,+1,0,+1,0,–1,0,–1,0,+1,0,–1,0,+1,0,+1,0,+1,0,+1,0,–1,0,+1,0,–1,0,

[0193] +1,0,+1,0,–1,0,–1,0,+1,0,–1,0,–1,0,–1,0,–1,0,–1,0,+1,0,–1,0,–1,0,+1,0,–1,0,+1,0,–1,0,+1,0,

[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,–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,

[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,

[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,

[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,+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,

[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,+1,0,0,0,0,0,0,0,–1,0,–1,0,–1,

[0209] 0,–1,0,–1,0,–1,0,–1,0,+1,0,+1,0,–1,0,+1,0,–1,0,–1,0,–1,0,–1,0,+1,0,–1,0,+1,

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

[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,+1,0,+1,0,+1,

[0225] 0,+1,0,+1,0,+1,0,–1,0,+1,0,+1}.

[0226] The LTF shown above 80MHz_2x This is only an example. As the standard progresses, the specific content of the basic LTF sequence can be updated, and this is not limited in the embodiments of the present application. The basic LTF sequence can be used to represent the LTF sequence under different bandwidths. As the basic LTF sequence changes, the representation of the LTF sequence can also change. Therefore, the embodiments of the present application do not limit the basic LTF sequence. The description of the basic subchannel and the basic LTF sequence here is also applicable below.

[0227] The LTF sequence shown above is not applicable to the case 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 the method can be effectively applied to the case 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.

[0228] Figure 3 1 is a flow chart of a communication method provided in an embodiment of the present application. For the relevant description of the first communication device and the second communication device, please refer to the description of the above communication system, which will not be described in detail here. Figure 3 As shown, the method includes:

[0229] 301. A first communication device generates a PPDU, where the PPDU includes an LTF carrying an LTF sequence, where the LTF sequence is determined based on a basic LTF sequence corresponding to a basic subchannel, where a length of the LTF sequence corresponds to a bandwidth of the PPDU, and where the bandwidth of the PPDU is greater than 320 MHz.

[0230] The following is a detailed introduction to each term involved in step 301.

[0231] First, PPDU

[0232] PPDU may include LTF. For example, the LTF may be EHT-LTF or 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, UHR-LTF is used as an example for explanation below when referring to specific examples. 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 is not limited.

[0233] Exemplarily, each field in the PPDU may occupy one or more OFDM symbols in the time domain dimension. The LTF provided in the embodiment of the present application may occupy one or more OFDM symbols. The number of OFDM symbols occupied by the LTF may be determined according to the LTF mode, such as being related to the GI and LTF modes. The embodiment of the present application does not limit the number of OFDM symbols occupied by different fields in the PPDU.

[0234] 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 embodiments of the present application. Exemplarily, 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. Exemplarily, 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 also 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.

[0235] Exemplarily, 80MHz may include 1024 subcarriers. Taking 80MHz including 1024 subcarriers, such as including a 996-tone RU, 5 DC subcarriers and 23 protection subcarriers as an example, N = (PPDU bandwidth / 80)*1024. For example, the relationship between the PPDU bandwidth and the number of subcarriers may be as follows:

[0236] 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.

[0237] When the LTF sequence is a 2x mode LTF sequence, among the 6144 subcarriers, 1 subcarrier is used for transmission in 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 may 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 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, more than 4 consecutive subcarriers with a value of 0 except the DC subcarrier and the protection subcarrier in the bandwidth of the PPDU may be null subcarriers.

[0238] 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 2 adjacent subcarriers except the DC subcarrier, the empty subcarrier, and the protection subcarrier. Exemplarily, among the 8192 subcarriers, there may be 23 protection subcarriers, 23 DC subcarriers, and (23×6+5*8) empty 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 may be empty subcarriers.

[0239] 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.

[0240] The bandwidth of the PPDU listed in the embodiments of the present application is only an example and should not be understood as a limitation on the embodiments of the present application.

[0241] Second, basic subchannel and basic LTF sequence

[0242] For example, the bandwidth of the basic subchannel 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.

[0243] Third, LTF and LTF sequence

[0244] 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 forms 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.

[0245] Exemplarily, the LTF sequence can be determined based on the basic LTF sequence. As an example, the bandwidth of the PPDU is 640 MHz, 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 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 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}.

[0246] LTF -4084,4084 =

[0247] {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 ,

[0248] 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 ,

[0249] 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 ,

[0250] 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 ,

[0251] 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 ,

[0252] 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 ,

[0253] 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 ,

[0254] 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)

[0255] 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) indicates 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.

[0256] LTF -3060,3060 =

[0257] {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 ,

[0258] 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 ,

[0259] 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 ,

[0260] 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 ,

[0261] 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 ,

[0262] 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)

[0263] 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 descriptions 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.

[0264] Fourth, unit subchannel, sequence corresponding to unit subchannel and rotation factor sequence

[0265] 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. In general, 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 may be referred to as a frequency domain rotation factor.

[0266] 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 40 MHz, and there is c in the above sequence (1). 2i-1 =c 2i , i=1,2,…,16, there exists 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 exist c 2i-1 ≠c 2i , i = 1, 2, ..., 16, the above sequence (2) may contain c 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)}.

[0267] 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.

[0268] Exemplarily, the LTF sequence can be obtained based on the period extension and phase flipping of the sequence corresponding to the unit subchannel in the frequency domain. The number of period extensions is equal to the length of the rotation factor sequence. For example, 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 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, j in the rotation factor sequence corresponds to a 90° phase rotation of the sequence corresponding to the unit subchannel, and -j corresponds to a 270° phase rotation of the sequence corresponding to the unit subchannel.

[0269] The following example illustrates the relationship between a unit subchannel, a sequence corresponding to the unit subchannel, and a rotation factor sequence.

[0270] 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)} is extended once, and 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)}Extension for the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} is extended for the second time, and 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)}Extension for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} The third extension is performed, and 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 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 refer to the following sequence (3), sequence (5), and sequence (6).

[0271] As another example, the bandwidth of the PPDU is 640 MHz, and the bandwidth of the unit subchannel is 20 MHz. Then the length of the rotation factor sequence is 640 MHz / 20 MHz=32, that is, the rotation factor sequence includes 32 rotation factors. For example, for sequence (1), 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 of (246:500) is c2, and so on, which are not listed here one by one. The sequence corresponding to the unit subchannel and the relevant description of the rotation factor can refer to the above example, which is not described in detail here. The LTF sequence can refer to the following sequence (3), sequence (4), and sequence (6).

[0272] 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)} is extended once, and 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)}Extension for the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} is extended for the second time, and 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)}Extension for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} The third extension is performed, and 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 refer to the sequence (7) below.

[0273] As another example, the bandwidth of the PPDU is 480MHz, and the bandwidth of the unit subchannel is 20MHz, then the length of the rotation factor sequence is 480MHz / 20MHz=24, that is, the rotation factor sequence includes 24 rotation factors. The sequence corresponding to the unit subchannel and the relevant description of the rotation factor, etc. can refer to the above example, which will not be described in detail here. The LTF sequence can refer to the sequence (8) below.

[0274] In an 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 basic LTF sequence. For example, the first communication device may store an LTF sequence, a basic LTF sequence, and a rotation factor sequence, etc., which are not listed here one by one. For the specific content of the LTF sequence, please refer to the following.

[0275] 302. The first communication device sends a PPDU, and correspondingly, the second communication device receives the PPDU.

[0276] 303. The second communication device performs channel estimation based on the LTF sequence.

[0277] Exemplarily, after the second communication device receives the PPDU, it can perform channel estimation based on the LTF sequence. Exemplarily, the LTF sequence can be saved in the second communication device, and the second communication device can perform channel estimation under the interference of noise based on the PPDU it receives and the LTF sequence it saves. The specific method of channel estimation is not limited in the embodiments of the present application.

[0278] The following is a detailed description of the LTF sequence involved in the embodiments of the present application.

[0279] Exemplarily, the LTF sequence may be any one of the following sequences (3) to (8).

[0280] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0281] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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)}(3)

[0288] 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 the following sequence (3b):

[0289] LTF -4084,4084 =

[0290] {LTF 80MHz_2x(1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0291] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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)}(3a)

[0298] LTF -4084,4084 =

[0299] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0300] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[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,-LTF80MHz_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,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(3b)

[0307] For sequence (3), sequence (3a), and sequence (3b), LTF 80MHz_2x (1:245) represents the first to the 245th elements 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) indicates 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 related instructions, please refer to Figure 3 , which will not be described in detail here. For the relevant description of the basic LTF sequence, please refer to the above text and will not be described in detail here. The relevant description of sequence (3) here, such as sequence (3a), sequence (3b) and the description of each parameter, is also applicable below.

[0308] Exemplarily, the above sequence (3a) can also be understood as the values ​​of the LTF sequence in 2x mode when the bandwidth is 640MHz on the subcarriers with index values ​​of -4080:4080 are:

[0309] {1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-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,

[0310] -1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-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,

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

[0312] -1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-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,

[0313] -1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,

[0314] -1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,

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[0317] -1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-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,

[0318] -1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-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,

[0319] -1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-1,0,1,0,1,0,-1,0,-1,0,-1,0,1,0,-1,0,-1,0,1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,1,0,1,0,-1,0,-1,0,-1,0,-1,0,1,0,1,0,1,0,-1,0,1,0,1,0,-1,0,-1,0,1,0,-1,0,-1,0,-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},

[0320] 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.

[0321] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0322] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0323] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0324] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0325] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),023 ,

[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)}(4)

[0329] For sequence (4), the LTF sequence may include the following sequence (4a) or sequence (4b):

[0330] LTF -4084,4084 =

[0331] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[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)}(4a)

[0339] LTF -4084,4084 =

[0340] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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)}(4b)

[0348] 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.

[0349] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0350] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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 80MHz_2x (757:1001),0 23 ,

[0355] LTF 80MHz_2x (1:245),LTF80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0356] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(5)

[0357] For sequence (5), the LTF sequence may include the following sequence (5a) or sequence (5b):

[0358] LTF -4084,4084 =

[0359] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0360] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0361] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0362] -LTF 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<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">

[0364] <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">

[0365] <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">

[0366] <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">

[0367] <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">

[0368] <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">

[0369] <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">

[0370] <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"> ,

[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)}(5b)

[0376] For the relevant descriptions about sequence (5a), sequence (5b) and sequence (5), please refer to the description of sequence (3) above, which will not be described in detail here.

[0377] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0378] -LTF 80MHz_2x(1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[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 ,

[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 ,

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

[0385] For sequence (6), the LTF sequence can include the following sequence (6a) or sequence (6b):

[0386] LTF -4084,4084 =

[0387] {-LTF 80MHz_2x (1:245), -LTF 80MHz_2x (246:500), 0, -LTF 80MHz_2x (502:756), -LTF 80MHz_2x (757:1001), 0 23 ,

[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)}(6a)

[0395] LTF -4084,4084 =

[0396] {LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

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

[0402] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0403] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(6b)

[0404] For the relevant descriptions about sequence (6a), sequence (6b) and sequence (6), please refer to the description of sequence (3) above, which will not be described in detail here.

[0405] ±{LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0406] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0407] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),023 ,

[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)}(7)

[0411] For sequence (7), the LTF sequence can include the following sequence (7a) or sequence (7b):

[0412] LTF -3060,3060 =

[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),0 23 ,

[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),0 23 ,

[0418] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(7a)

[0419] LTF -3060,3060 =

[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] LTF 80MHz_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,LTF80MHz_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),0 23 ,

[0425] -LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001)}(7b)

[0426] For the relevant descriptions about sequence (7a), sequence (7b) and sequence (7), please refer to the description of sequence (3) above, which will not be described in detail here.

[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 ,

[0430] LTF 80MHz_2x (1:245),-LTF 80MHz_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)}(8)

[0433] For sequence (8), the LTF sequence can include the following sequence (8a) or sequence (8b):

[0434] LTF -3060,3060 =

[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),0 23 ,

[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),0 23 ,

[0440] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(8a)

[0441] LTF -3060,3060 =

[0442] {-LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0443] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0444] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),LTF 80MHz_2x (757:1001),0 23 ,

[0445] LTF 80MHz_2x (1:245),-LTF 80MHz_2x (246:500),0,-LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0446] LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,-LTF80MHz_2x (502:756),-LTF 80MHz_2x (757:1001),0 23 ,

[0447] -LTF 80MHz_2x (1:245),LTF 80MHz_2x (246:500),0,LTF 80MHz_2x (502:756),-LTF 80MHz_2x (757:1001)}(8b)

[0448] For the relevant descriptions about sequence (8a), sequence (8b) and sequence (8), please refer to the description of sequence (3) above, which will not be described in detail here.

[0449] 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 MRU or RU, 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 MRU or RU, making the LTF sequence compatible with various RU or MRU. The following introduces MRU and pilot rotation respectively.

[0450] (1)MRU / RU

[0451] 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 performances depending on the position and size of the MRU in the bandwidth of the PPDU. In addition, the trade-off between the signaling overhead and spectrum efficiency for indicating the MRU needs to be considered. Therefore, the embodiment of the present application comprehensively considers the PAPR performance, signaling overhead and spectrum efficiency, and provides two MRU modes (such as the first MRU mode and the 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.

[0452] 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 embodiment of the present application, and can also be used for other MRUs. That is, the LTF sequence shown in the embodiment of the present application can also well meet more MRUs. The MRU mode shown in the embodiment of the present application can also be called an MRU pattern or an MRU style or an MRU type, etc.

[0453] The following describes the MRU involved in the PPDU shown in the embodiment of the present application.

[0454] As an example, when the bandwidth of the PPDU is 640 MHz, the MRU of the 640 MHz PPDU includes any of the following:

[0455] MRU of 7×996 subcarriers (also called 7×996-tone MRU), MRU of 6×996 subcarriers (also called 6×996-tone MRU), MRU of 5×996 subcarriers (also called 5×996-tone MRU), MRU of 7×996+484 subcarriers (also called 7×996+484-tone MRU), MRU of 6×996+484 subcarriers (also called 6×996+484-tone MRU), MRU of 5×996+484 subcarriers (also called 5×996+484-tone MRU), MRU of 4×996+484 subcarriers (also called 4×996+484-tone MRU).

[0456] For example, if the 40 MHz sub-channel is not punctured in the 640 MHz, the MRU includes any of the following: Figure 4a The MRU of 7×996 subcarriers is shown as Figure 4b The MRU of 6×996 subcarriers shown in FIG. Figure 4c An MRU of 5×996 subcarriers is shown. Figures 4a to 4c The MRU shown may be understood as an MRU in the first MRU mode corresponding to 640 MHz.

[0457] For example, if the punctured subchannel in 640 MHz includes a 40 MHz subchannel, then the MRU includes any of the following: Figure 4d The MRU of 7×996+484 subcarriers is shown as Figure 4e The MRU of 6×996+484 subcarriers shown is Figure 4f The MRU of 5×996+484 subcarriers shown is Figure 4g The MRU of 4×996+484 subcarriers is shown. Figure 4d to Figure 4gThe MRU shown may be understood as an MRU in the second MRU mode corresponding to 640 MHz.

[0458] When the PPDU bandwidth is 640MHz, Figure 4a , Figure 4b , Figure 4d , Figure 4e The effective bandwidth of the MRU shown is greater than or equal to 480 MHz. The effective bandwidth is the remaining bandwidth of the 640 MHz bandwidth excluding the punctured subchannels. For example, when the bandwidth of the PPDU is 640 MHz, Figure 4c , Figure 4f and Figure 4g The effective bandwidth of the MRU shown is less than or equal to 480 MHz. Figure 4c , Figure 4f and Figure 4g The MRU shown can also be reused for the MRU of the 480MHz PPDU. Thus, the types of MRUs of the PPDU can be effectively reduced, and the signaling overhead caused by indicating the MRU can be reduced. For example, Figure 4c , Figure 4f and Figure 4g The MRU shown may also be referred to as an MRU in the third MRU mode corresponding to 480 MHz.

[0459] As another example, when the bandwidth of the PPDU is 480 MHz, the MRU of the 480 MHz PPDU includes: Figure 5a The MRU of 5×996+484 subcarriers shown is Figure 5b The MRU of 5×996 subcarriers is shown as Figure 5c The MRU of 4×996+484 subcarriers is shown as Figure 5d An MRU of 4×996 subcarriers is shown. Figure 5a to Figure 5d The MRU shown may be referred to as an MRU in the fourth MRU mode corresponding to 480 MHz.

[0460] (2) Pilot rotation

[0461] 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, so pilot rotation is introduced for pilot correction, such as the P matrix (P as shown below) LTF ) and the R matrix (shown below as R LTF ). That is, the first communication device can generate a PPDU based on the LTF sequence and the P matrix and the R matrix.

[0462] The pilot rotation that exists during LTF transmission, the corresponding spatial mapping matrix is ​​as follows:

[0463]

[0464] Among them, K pilot Indicates the index of the pilot subcarrier. LTF is a The matrix of Indicates the number of spatial streams corresponding to the LTF sequence.

[0465] For example, R LTF With P LTF The following relationship can be satisfied:

[0466]

[0467] Among them, m represents the mth row of the matrix, and n represents the nth column of the matrix.

[0468] For example, P LTF It can be as follows:

[0469]

[0470] 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. Exemplarily, the above matrix P 4×4 , matrix P 6×6 , matrix P 8×8 They are as follows:

[0471]

[0472]

[0473]

[0474] It can be understood that the matrix P shown above 4×4 , matrix P 6×6 , matrix P 8×8 This is only an example. As the standard progresses, the above matrices may also change, and the present application embodiment does not limit this. When the above matrices change, the LTF sequence can also be constructed based on the changed matrix and MRU, and the LTF sequence constructed in this case also belongs to the protection scope of the present application embodiment.

[0475] 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.

[0476] As another example, when the bandwidth of the PPDU is 480 MHz, the LTF sequence may be sequence (7) or sequence (8).

[0477] The MRU shown in the embodiment of the present application is only an example. In actual applications, the MRU of the PPDU can be more, and the embodiment of the present application does not limit this. That is, when the bandwidth of the PPDU is 640MHz or 480MHz, the first communication device and the second communication device can both apply the LTF sequence provided in the embodiment of the present application.

[0478] 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.

[0479] In view of the LTF sequence, PPDU bandwidth, MRU / RU, and pilot rotation shown in the embodiment of the present application, Figure 3 The method shown can also be understood as:

[0480] As an 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 according to 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 a plurality of 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). The first communication device sends the above LTF sequence.

[0481] 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 according to 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 such as any one of sequences (3) to (8).

[0482] 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; wherein the RU / MRU is located within the above bandwidth, the RU / MRU includes a plurality of continuous 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.

[0483] 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 according to 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).

[0484] 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.

[0485] 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 according to 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 a plurality of 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). The first communication device sends the above LTF sequence.

[0486] 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 according to 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 such as any one of sequences (3) to (8).

[0487] As another example, the first communication device maps the sequence segments corresponding to the positions of the subcarriers in the RU / MRU included in the bandwidth to the subcarriers 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 bandwidth, the RU / MRU includes a plurality of 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). The first communication device sends the above LTF sequence.

[0488] 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 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, 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).

[0489] The bandwidth shown above may be the bandwidth of the PPDU, and the RU / MRU may be the RU / MRU of the PPDU.

[0490] 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.

[0491] The following describes the construction method of the LTF sequence provided in the embodiments of the present application.

[0492] 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 can save the LTF sequence. It can be understood that the construction method shown below is shown with the bandwidth of the PPDU as 480MHz or 640MHz as an example, but the construction method of the LTF sequence when the bandwidth of the PPDU is greater than 640MHz is also applicable to the embodiment of the present application. When the bandwidth of the PPDU is greater than 640MHz, or when the bandwidth of the PPDU is greater than 320MHz except for 480MHz and 640MHz Other bandwidths (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 belongs to the protection scope of the embodiment of the present application.

[0493] 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, quantity, 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, various RUs and MRUs that may appear in the two PPDUs and the RUs and MRUs existing in 802.11be are considered, and various pilot rotation methods are considered. The LTF sequence is constructed with the optimization goal of minimizing the maximum PAPR of the RU / MRU, 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 sequence corresponding to all RUs or MRUs, or make the maximum PAPR of the sequence corresponding to all RUs or MRUs smaller. Exemplarily, the sequence corresponding to the minimum PAPR value is determined as the LTF sequence from the maximum PAPR values ​​of multiple sequences (also referred to as candidate LTF sequences). The 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, so that the constructed LTF sequence has better PAPR performance.

[0494] 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.

[0495] Exemplarily, the process of constructing an LTF sequence may be as follows:

[0496] % Parameter initialization %

[0497] Set the PPDU bandwidth to BW = 480 or 640 MHz;

[0498] Set the unit subchannel bandwidth to BW_{element} = 20MHz, 40MHz (can also be set to 80MHz, 160MHz, etc.);

[0499] Calculate the number of subchannels as BW / BW_{element};

[0500] The frequency domain rotation factor sequence corresponding to each unit subchannel has two possibilities: all 1 or all -1, and a total of 2 (BW / BW_{element}) possible rotation factor sequences;

[0501] %2xLTF sequence calculation process%

[0502] Start loop

[0503] For each possible rotation factor sequence

[0504] For each RU / MRU

[0505] For each pilot rotation corresponding to the spatial stream

[0506] Calculate the PAPR of the 2xLTF sequence;

[0507] Calculate the maximum PAPR of all RU / MRU and all pilot rotation conditions in the rotation factor sequence;

[0508] End the loop

[0509] Find the minimum value of the maximum values ​​of the PAPRs of all rotation factor sequences, and find the rotation factor sequence corresponding to the minimum value.

[0510] 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.

[0511] The first MRU mode based on 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 the relevant description of the first MRU mode, please refer to the above Figures 4a to 4cThe relevant description is not described in detail here. The following is an example of the bandwidth of the unit subchannel being 20 MHz and 40 MHz. The bandwidth of the unit subchannel shown in the embodiment of the present application is only an example. In a specific implementation, unit subchannels of other bandwidths may also be involved when constructing the LTF sequence.

[0512] Example 1: First MRU mode, the bandwidth of the unit subchannel is 40 MHz

[0513] 1A. When the bandwidth of PPDU is BW=640MHz and the bandwidth of unit subchannel 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 value corresponding to each unit subchannel can be either all 1 or all -1, that is, the rotation factor sequence LTF_{40MHzrotation}={a1,…,a i ,…,a 16}, where any a i = ±1. Now we get a total of 2 (BW / BW_{element}) = 65536 possible rotation factor sequences. For example, c 2i-1 =c 2i =a i , i=1,2,…,16. About c 2i-1 =c 2i For the relevant description, please refer to the description of the unit subchannel in step 301, which will not be described in detail here. For the convenience of reference and brevity of the following text, the embodiment of the present application uses 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 embodiment of the present application should not be understood as a limitation on the embodiment of the present application.

[0514] 1B. For any 2xLTF sequence, since OFDMA transmission and preamble puncturing may divide a 2xLTF sequence into multiple subsequences, each subsequence is transmitted in a different RU / MRU. At this time, only part of the sequence on each RU / MRU is used for actual wireless transmission. Therefore, the PAPR of the subsequences occupied by different RU / MRUs can be calculated, so that the LTF sequence can be effectively determined. In the 640MHz PPDU, the embodiment of the present application not only considers the MRU included in the first MRU mode in 640MHz. 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. 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 needs to be phase calibrated. 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.

[0515] 1C. For each candidate 2xLTF sequence, pilot rotations corresponding to various numbers of spatial streams and various MRU / RU patterns are considered, and PAPR is calculated respectively.

[0516] PAPR can satisfy the following formula:

[0517]

[0518] The above formula can also be expressed as: PAPR = max(abs(ifft(LTF,N)).^2) / mean(abs(ifft(LTF,N)).^2). Exemplarily, 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. Exemplarily, 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.

[0519] 1D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the above 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{40MHzrotation} corresponding to the minimum value as ±{1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,1,-1,1}, which is as follows:

[0520] or,

[0521] {1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,1,1,-1,1}.

[0522] 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.

[0523] {LTF 80MHz_2x (1:245)} is extended once, the rotation factor is the first element -1 in the rotation factor sequence, and 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)}Extension for the second time, the rotation factor is the fifth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} is extended for the second time, and 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)}Extension for the third time, the rotation factor is the ninth element in the rotation factor sequence; {LTF 80MHz_2x (246:500)} The third extension is performed, and 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 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 LTF sequence shown in the above sequence (3b) can be obtained by the above method.

[0524] The two rotation factor sequences are opposite to each other, and the maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0525] 80MHz sub-channel: 9.6367dB;

[0526] 160MHz sub-channel: 10.4040dB;

[0527] 320MHz subchannel: 10.8630dB;

[0528] 640MHz subchannel: 10.8988dB.

[0529] Exemplarily, the above-mentioned 80MHz sub-channel considers RUs or MRUs with bandwidths 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 bandwidths 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 bandwidths 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 bandwidths greater than 320MHz and less than or equal to 640MHz, including the RU or MRU in the first MRU mode in the embodiment of the present application.

[0530] The MRU / RU included in the subsequent 80MHz subchannel, 160MHz subchannel, 320MHz subchannel, 640MHz subchannel and 480MHz subchannel will not be described in detail. For example, the 480MHz subchannel shown below considers the RU / MRU with a bandwidth greater than 320MHz and less than or equal to 480MHz, which will not be described in detail below.

[0531] The specific content of the LTF sequence based on the first MRU mode and the 40MHz subchannel rotation factor can refer to the above sequence (3).

[0532] Embodiment 2: First MRU mode, unit subchannel is 20MHz

[0533] 2A. When the bandwidth of PPDU is BW=640MHz and the bandwidth of unit subchannel is BW_{element}=20MHz, the number of sequences corresponding to the unit subchannel is BW / BW_{element}=32. The rotation factor sequence value corresponding to each unit subchannel can be either all 1 or all -1, that is, 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. Now we get 2 (BW / BW_{element}) = 4295000000 possible rotation factor sequences, which is about 4.29 billion, with extremely high computational complexity. Considering that each sequence may have multiple MRU / RUs, and each MRU / RU may have multiple pilot rotation modes, 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.

[0534] Based on local symmetry, the rotation factor sequence shown in the embodiment of the present application satisfies at least one of the following:

[0535] 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 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, i is greater than 0 and is 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 any (2*i-1)th element and the (2*i)th element in the rotation factor sequence have the same value as the two elements at the symmetrical positions of the two elements in the sequence. For example, BW=640MHz, BW_{element}=20MHz, and i is less than or equal to 16. If i=1, the first group of elements are the first and second elements in the rotation factor sequence, and the second group of elements whose positions are symmetrical to those of the first group of elements can be the last and second to last elements in the rotation factor sequence, that is, the 32nd and 31st elements. For another example, if i=2, the first group of elements are the third and fourth elements in the rotation factor sequence, and the second group of elements in the rotation factor sequence are the 30th and 29th elements. And so on, and they are not listed here one by one.

[0536] 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 are elements whose positions are 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. The local symmetry shown here can be local negative symmetry, which means that any (2*j-1)th element and (2*j)th element in the rotation factor sequence are opposite to the values ​​of the two elements at the symmetrical positions of these two elements in the sequence. i is not equal to j. For example, BW=640MHz, BW_{element}=20MHz, and j is less than or equal to 16. If i=1, j is not equal to 1. If j=3, the first group of elements may be the 5th and 6th elements in the rotation factor sequence, and the second group of elements may be the 28th and 27th elements in the rotation factor sequence. The value of the 5th element is the opposite of the value of the 28th element, and the value of the 6th element is the opposite of the value of the 27th element. And so on, which are not listed here one by one.

[0537] Exemplarily, according to the above local symmetry, all possible values ​​of two adjacent elements in any group of the rotation factor sequence and two elements in the symmetric position are shown in Table 1:

[0538] Table 1

[0539]

[0540]

[0541] The bandwidth length corresponding to 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) =16777216, which is about 16.8 million, which is much lower than the original 4.29 billion. Because after the LTF sequence is inverted, the PAPR value of the corresponding LTF sequence remains unchanged. Therefore, the number of candidate LTF sequences is further reduced by half.

[0542] The local symmetry shown in the embodiments of the present application is not only applicable to the second embodiment, but also to other embodiments, such as the first embodiment, the third embodiment to the eighth embodiment, etc.

[0543] 2B. For the relevant instructions on step 2B, please refer to step 1B, which will not be described in detail here.

[0544] 2C. For the relevant instructions on step 2C, please refer to step 1C, which will not be described in detail here.

[0545] 2D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the above 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{20MHzrotation} corresponding to the minimum value as ±{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}, which is as follows:

[0546] or,

[0547] {-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};

[0548] The two rotation factor sequences are opposite to each other. The maximum PAPR of each subchannel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0549] 80MHz sub-channel: 9.6367dB;

[0550] 160MHz sub-channel: 10.4040dB;

[0551] 320MHz subchannel: 10.6326dB;

[0552] 640MHz subchannel: 10.8305dB.

[0553] The specific content of the LTF sequence based on the first MRU mode and the 20MHz subchannel rotation factor can refer to the above sequence (4).

[0554] The second MRU mode based on 640MHz PPDU is a more detailed MRU constructed under the premise of retaining 484-tone puncturing. The following takes the bandwidth of the unit subchannel as 40MHz and 20MHz as examples to explain respectively. For the relevant description of the second MRU mode, please refer to the above Figure 4d to Figure 4g The relevant description will not be described in detail here.

[0555] Example 3, second MRU mode, unit subchannel is 40MHz

[0556] 3A. For the specific instructions of step 3A, please refer to step 1A, which will not be described in detail here.

[0557] 3B. In the 640MHz PPDU, the MRU included in the second MRU mode in 640MHz 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, 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.

[0558] For other instructions on step 3B, please refer to step 1B, which will not be described in detail here.

[0559] 3C. For the relevant instructions on step 3C, please refer to step 1C, which will not be described in detail here.

[0560] 3D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the above 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{40MHzrotation} corresponding to the minimum value as ±{1,1,-1,-1,-1,-1,-1,-1,1,1,-1,1,1,-1,-1}, which is as follows:

[0561] or,

[0562] {-1,-1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,1,1}.

[0563] The two rotation factor sequences are opposite to each other, and the maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0564] 80MHz sub-channel: 9.6367dB;

[0565] 160MHz sub-channel: 10.9316dB;

[0566] 320MHz subchannel: 10.7971dB;

[0567] 640MHz subchannel: 11.0946dB.

[0568] 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).

[0569] Embodiment 4, second MRU mode, unit subchannel is 20MHz

[0570] 4A. For the relevant instructions on step 4A, please refer to step 2A, which will not be described in detail here.

[0571] 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.

[0572] 4B. For the relevant instructions on step 4B, please refer to step 3B, which will not be described in detail here.

[0573] 4C. For the relevant instructions of step 4C, please refer to step 3C or step 1C, which will not be described in detail here.

[0574] 4D. 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{20MHzrotation} corresponding to the minimum value as ±{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}, which is as follows:

[0575] or,

[0576] {-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};

[0577] The two rotation factor sequences are opposite to each other. The maximum PAPR of each subchannel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0578] 80MHz sub-channel: 9.6367dB;

[0579] 160MHz sub-channel: 10.9316dB;

[0580] 320MHz subchannel: 10.7971dB;

[0581] 640MHz subchannel: 11.0946dB.

[0582] The specific content of the LTF sequence based on the second MRU mode and the 20MHz subchannel rotation factor can refer to the above sequence (1).

[0583] The effective bandwidth of the 640MHz PPDU is less than or equal to 480MHz, such as the outermost 160MHz subchannel is punctured 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 above Figure 4c , Figure 4f , Figure 4g and Figure 4b The relevant description of {6×996-tone MRU 1 and 6×996-tone MRU 4} in the description will not be described in detail here. Embodiment 5 and Embodiment 6 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, Embodiment 5 and Embodiment 6 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. Embodiment 5 and Embodiment 6 shown below can be the construction method of the LTF sequence in the third MRU mode of the 480MHz PPDU. The above-mentioned Embodiments 1 to 4 can be the construction method of the LTF sequence when the effective bandwidth of the 640MHz PPDU is greater than or equal to 480MHz.

[0584] The third MRU pattern (MRU pattern 3) multiplexes {6×996-tone MRU 1 and 6×996-tone MRU 4 (such as Figure 4b ), 5×996+484-tone MRU (such as Figure 4f), 5×996-tone MRU (such as Figure 4c ), 4×996+484-tone MRU (such as Figure 4g )}. 5×996+484-tone MRU in MRU pattern 3 in 640MHz PPDU (such as Figure 4f ), 5×996-tone MRU (such as Figure 4c ), 4×996+484-tone MRU (such as Figure 4g )、6×996-tone MRU1(such as Figure 4b ) and 6×996-tone MRU 4 (such as Figure 4b ), the above MRU has an effective transmission bandwidth less than or equal to 480MHz due to the 160MHz channel being punched on the outermost side, so the above MRU can be used to transmit 480MHz PPDU. Since the above effective bandwidth is greater than the maximum PPDU bandwidth of 320MHz in the 802.11be standard, it also needs to be compatible with the RU / MRU in 802.11be.

[0585] In the design of 2xLTF sequence for 480MHz PPDU based on MRU pattern 3, the embodiment of the present application constructs 2xLTF sequence based on 20MHz unit subchannel and 40MHz unit subchannel respectively. Since the MRU pattern 3 reuses part of the MRU in 640MHz, the expression of LTF sequence constructed by the embodiment of the present application may be the same as the above sequence (1).

[0586] Example 5: The third MRU mode, the unit subchannel is 40 MHz

[0587] 5A. MRU pattern 3 reuses some MRUs in the 640MHz PPDU, so the bandwidth of the PPDU is 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 value corresponding to each unit subchannel can be either all 1 or all -1, that is, LTF_{40MHzrotation} = {a1,…,a i ,…,a 16}, where any a i = ±1. Now we get a total of 2 (BW / BW_{element}) = 65536 possible rotation factor sequences.

[0588] For the relevant instructions about step 5A, please refer to step 1A, etc., which will not be described in detail here.

[0589] 5B. In the 640MHz PPDU, the MRU included in the third MRU mode in 640MHz is considered. In addition, the RU / MRU defined in 802.11be is 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 considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU and 4×996-tone RU.

[0590] For relevant instructions on pilot rotation, P matrix and R matrix, etc., please refer to step 1B, etc., which will not be described in detail here.

[0591] 5C. For the relevant instructions on step 5C, please refer to step 1C, etc., which will not be described in detail here.

[0592] 5D. For the i-th 2xLTF sequence, calculate the pilot rotations corresponding to all the above 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{40MHzrotation} corresponding to the minimum value as ±{-1,-1,1,1,1,1,-1,1,-1,1,1,1,1,-1,-1}, which is as follows:

[0593] {1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1}; or,

[0594] {-1,-1,1,1,1,1,-1,1,-1,1,1,1,1,-1,-1}.

[0595] The two rotation factor sequences are opposite to each other, and the maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0596] 80MHz sub-channel: 9.6367dB;

[0597] 160MHz sub-channel: 10.9316dB;

[0598] 320MHz subchannel: 10.2876dB;

[0599] 640MHz subchannel: 10.9297dB.

[0600] 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).

[0601] Example 6: The third MRU mode, the unit subchannel is 20 MHz

[0602] 6A. MRU pattern 3 reuses some MRUs in the 640MHz PPDU, so the bandwidth of the PPDU is BW=640MHz. When the unit subchannel bandwidth is BW_{element}=20MHz, the number of unit subchannels is BW / BW_{element}=32.

[0603] For the relevant description of step 6A, reference may be made to step 2A, such as the relevant description of local symmetry, positive local symmetry, negative local symmetry and Table 1 in step 2A, which will not be described in detail here.

[0604] 6B. For the relevant instructions on step 6B, please refer to step 5B or 1B, etc., which will not be described in detail here.

[0605] 6C. For the relevant instructions on step 6C, please refer to step 1C, etc., which will not be described in detail here.

[0606] 6D. 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{20MHzrotation} corresponding to the minimum value as ±{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}, which is as follows:

[0607] or,

[0608] {-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}

[0609] The two rotation factor sequences are opposite to each other. The maximum PAPR of each subchannel of the 640MHz PPDU corresponding to the rotation factor sequence is as follows:

[0610] 80MHz sub-channel: 9.6367dB;

[0611] 160MHz sub-channel: 10.9316dB;

[0612] 320MHz subchannel: 10.2876dB;

[0613] 640MHz subchannel: 10.9297dB.

[0614] 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).

[0615] MRU based on 480MHz PPDU can refer to Figure 5a to Figure 5d The relevant description is not described in detail here. The seventh and eighth embodiments shown below are constructed based on the MRU of 480MHz PPDU, or based on the fourth MRU mode of 480MHz PPDU. The fourth MRU mode: {5×996+484-tone MRU (such as Figure 5a ), 5×996-tone MRU (such as Figure 5b ), 4×996+484-tone MRU (such as Figure 5c ), 4×996-tone MRU (such as Figure 5d )}. The construction methods shown in Embodiment 7 and Embodiment 8 may be applicable to 480MHz PPDU.

[0616] Embodiment 7, fourth MRU mode, unit subchannel is 40MHz

[0617] 7A. When the bandwidth of PPDU is BW=480MHz and the bandwidth of unit subchannel is BW_{element}=40MHz, the number of unit subchannels is BW / BW_{element}=12. The frequency domain rotation factor sequence value 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. Now we get a total of 2 (BW / BW_{element}) = 4096 possible rotation factor sequences. For example, c 2i-1 =c 2i =a i , i=1,2,…,12.

[0618] For other instructions about step 7A, please refer to step 1A, etc., which will not be described in detail here.

[0619] 7B. In the 480MHz PPDU, the embodiment of the present application considers MRU pattern 4 based on 480MHz 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, and RU defined in 802.11be are considered, such as 996-tone RU, 2×996-tone RU, 3×996-tone RU and 4×996-tone RU.

[0620] For other instructions about step 7B, please refer to step 6B or 1B, etc., which will not be described in detail here.

[0621] 7C. For the relevant instructions on step 7C, please refer to step 6C or 1C, etc., which will not be described in detail here.

[0622] 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{40MHzrotation} corresponding to the minimum value as ±{1,-1,1,1,-1,-1,-1,-1,-1,1,1,-1}, as shown below:

[0623] {1,-1,1,1,-1,-1,-1,-1,1,1,1,-1}; or,

[0624] {-1,1,-1,-1,1,1,1,-1,-1,-1,1}.

[0625] The two rotation factor sequences are opposite to each other, and the maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0626] 80MHz sub-channel: 9.6367dB;

[0627] 160MHz sub-channel: 10.3499dB;

[0628] 320MHz subchannel: 10.2876dB;

[0629] 480MHz subchannel: 10.8107dB.

[0630] 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).

[0631] Embodiment 8, fourth MRU mode, unit subchannel is 20MHz

[0632] 8A. The bandwidth of PPDU is BW = 480MHz, the bandwidth of unit subchannel is BW_{element} = 20MHz, and the number of sequences corresponding to unit subchannel is BW / BW_{element} = 24. The rotation factor sequence value corresponding to each unit subchannel can be either all 1 or all -1, that is, LTF_{20MHzrotation} = {a1,…,a i ,…,a 24}, where any a i = ±1. Now we get a total of 2 (BW / BW_{element}) = 16777216 possible rotation factor sequences, which is about 16.78 million. For example, c i =a i , i=1,2,…,24.

[0633] 8B. For the relevant instructions on step 8B, please refer to step 7B, which will not be described in detail here.

[0634] 8C. For the relevant instructions on step 8C, please refer to step 7C, etc., which will not be described in detail here.

[0635] 8D. 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 value {PAPR_{max,i}}_{min}, and obtain the rotation factor sequence LTF_{20MHzrotation} corresponding to the minimum value as ±{-1,-1,1,1,1,1,1,1,1,1,1,1,-1,-1,-1,-1,-1,-1,-1,-1,1,-1}, which is as follows:

[0636] or,

[0637] {1,1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,-1,1,1,-1,-1,-1,1,1,-1,-1,1}.

[0638] The two rotation factor sequences are opposite to each other, and the maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the rotation factor sequence is as follows:

[0639] 80MHz sub-channel: 9.6367dB;

[0640] 160MHz sub-channel: 10.4040dB;

[0641] 320MHz sub-channel: 10.4665dB;

[0642] 480MHz subchannel: 10.5380dB.

[0643] 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).

[0644] The above-mentioned method of using local symmetry to reduce complexity and realize selecting 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.

[0645] Exemplarily, when the frequency domain sequence is even symmetric, its time domain signal contains only the real part, and the 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 a partial sequence in the frequency domain sequence), and when the frequency domain sequence is odd symmetric, its time domain signal contains only the imaginary part, and the 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 is superimposed with the even symmetric sequence, 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.

[0646] Therefore, when the rotation factor sequence also satisfies the above relationship as shown in the frequency domain sequence, a lower PAPR may also exist. 4i+1 ,c 4I+2 ,c 4i+3 ,c 4I+4 ]=±[-c N+1-(4i+1) ,c N+1-(4I+3) ,-c N+1-(4i+3) ,c N+1-(4i+4) ].

[0647] 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.

[0648] Based on the above method, illustratively, the sequence and corresponding PAPR of the 20MHz subchannel rotation in the first MRU mode, the second MRU mode, and the third MRU mode are as follows:

[0649] 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}.

[0650] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0651] 80MHz sub-channel: 9.6367dB;

[0652] 160MHz sub-channel: 10.6559dB;

[0653] 320MHz subchannel: 10.9196dB;

[0654] 640MHz subchannel: 10.9602dB.

[0655] 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,-1}.

[0656] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0657] 80MHz sub-channel: 10.5309dB;

[0658] 160MHz sub-channel: 11.0047dB;

[0659] 320MHz subchannel: 10.4322dB;

[0660] 640MHz subchannel: 11.1040dB.

[0661] For the third MRU mode, when 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}.

[0662] The maximum PAPR of the sub-channel of the 2xLTF sequence corresponding to the above rotation factor sequence is as follows:

[0663] 80MHz sub-channel: 10.5309dB;

[0664] 160MHz sub-channel: 11.0047dB;

[0665] 320MHz subchannel: 10.4322dB;

[0666] 640MHz subchannel: 10.9325dB.

[0667] 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 the present 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.

[0668] It is understandable that the construction method of the LTF sequence shown above is shown by taking the bandwidth of the PPDU as 480MHz or 640MHz as an example. In a specific implementation, the bandwidth of the PPDU can be larger. The LTF sequence when the bandwidth of the PPDU is greater than 640MHz can also be determined according to the above construction method, or other LTF sequences not shown when the bandwidth of the PPDU is 480MHz or 640MHz can also be determined according to the above construction method. Therefore, any LTF sequence obtained according to the above construction method belongs to the protection scope of the embodiments of the present application.

[0669] The following is an introduction to the communication device provided in the embodiments of the present application.

[0670] The present application divides the functional modules of the communication device according to the above 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 integrated modules can be implemented in the form of hardware or software functional modules. It should be noted that the division of modules in the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. Figures 6 to 8 The communication device according to the embodiment of the present application is described in detail.

[0671] Figure 6 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application, such as Figure 6 As shown, 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 for data processing. For example, the transceiver module 602 can also be called a communication interface or a communication module.

[0672] 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.

[0673] Exemplarily, the processing module 601 is used to generate a PPDU; the transceiver module 602 is used to send or output the PPDU.

[0674] It is understandable that the transceiver module 602 can send the PPDU to other communication devices, or the transceiver module 602 outputs the PPDU from the processing module 601 to other components or other functional modules in the first communication device. The relevant description of the output of other information by the transceiver module is similar and will not be described in detail below.

[0675] 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.

[0676] 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.

[0677] Optionally, the communication device may further include a storage module, which may be used to store instructions and / or data, and the processing module 601 may read the instructions and / or data in the storage module so that the communication device implements the aforementioned method embodiment. Exemplarily, the storage module may be used to store information such as LTF sequence.

[0678] 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.

[0679] 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.

[0680] The above describes the communication device of the embodiment of the present application, and the following describes possible product forms of the communication device. Figure 6Any form of product with the functions of the communication device described above falls within the protection scope of the embodiments of the present application. It should also be understood that the following description is only an example and does not limit the product form of the communication device of the embodiments of the present application to this.

[0681] In one possible implementation, Figure 6 In the communication device shown, the processing module 601 may be one or more processors, the transceiver module 602 may be a transceiver, or the transceiver module 602 may also be a sending module and a receiving module, the sending module may be a transmitter, the receiving module may be a receiver, and the sending module and the receiving module are integrated into one 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 mode of the processor and the transceiver. In the process of executing the above method, the process of sending information in the above method can be understood as the process of outputting the above information by the processor. When outputting the above information, the processor outputs the above information to the transceiver so that it is transmitted by the transceiver. After the above information is output by the processor, it may also need to be processed in other ways before it reaches 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 in other ways before it is received by the processor.

[0682] like Figure 7a As shown, the communication device 70 includes one or more processors 720 and a transceiver 710 .

[0683] 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.

[0684] Exemplarily, the processor 720 is used to generate a PPDU; and the transceiver 710 is used to send the PPDU.

[0685] In some 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.

[0686] The transceiver 710 is configured to receive a PPDU; and the processor 720 is configured to perform channel estimation based on an LTF sequence.

[0687] It can be understood that the specific description of the transceiver and the processor shown in the embodiments of the present application is only an example. For the specific functions or execution steps of the transceiver and the processor, reference can be made to the above-mentioned method embodiments, which will not be described in detail here.

[0688] 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.

[0689] exist Figure 7a In various implementations of the communication device shown, the transceiver may include a receiver and a transmitter, wherein the receiver is used to perform a receiving function (or operation) and the transmitter is used to perform a transmitting function (or operation). The transceiver is used to communicate with other devices / devices through a transmission medium.

[0690] Optionally, the communication device 70 may also 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 may 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 one or more memories may be included in the processor. Exemplarily, the memory may be used to store LTF sequences, etc.

[0691] The specific connection medium between the transceiver 710, the processor 720 and the memory 730 is not limited in the embodiment of the present application. Figure 7a The memory 730, the processor 720 and the transceiver 710 are connected via a bus 740. Figure 7a The connections between the other components are shown in bold lines, which are only for illustration and are not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 7a Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0692] 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 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 method disclosed in the embodiments of the present application may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor, etc.

[0693] In the embodiment of the present application, the memory may include, but is not limited to, non-volatile memory 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 codes 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 to this. 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.

[0694] Exemplarily, the processor 720 is mainly used to process the communication protocol and communication data, and to control the entire communication device, execute the software program, and process the data of the software program. The memory 730 is mainly used to store the software program and data. The transceiver 710 may include a control circuit and an antenna. The control circuit is mainly used to convert the baseband signal and the radio frequency signal and to process the radio frequency signal. The antenna is mainly used to transmit and receive radio frequency signals in the form of electromagnetic waves. The input and output devices, such as a touch screen, a display screen, a keyboard, etc., are mainly used to receive data input by the user and output data to the user.

[0695] When the communication device is turned 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 sends the radio frequency signal outward 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.

[0696] In another implementation, the RF circuit and antenna may be arranged independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be arranged remotely from the communication device.

[0697] It is understandable that the communication device shown in the embodiment of the present application may also have Figure 7aThe embodiments of the present application do not limit the number of components and the like. The methods executed by the processor and the transceiver shown above are only examples, and the specific steps executed by the processor and the transceiver can refer to the methods described above.

[0698] Figure 7b is a schematic diagram of the structure of another communication device provided in an embodiment of the present application. Figure 7b As shown, 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, the memory, the transmitter, the receiver, and the display screen, please refer to Figure 7a , which will not be described in detail here. The signal detector can be used to detect signals, such as detecting reference signals or demodulating 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 embodiments of the present application.

[0699] In another possible implementation, Figure 6 In the communication device shown, the processing module 601 may be one or more logic circuits, and the transceiver module 602 may be an input / output interface, or 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, and 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. Figure 8 As shown, Figure 8 The communication device shown includes a logic circuit 801 and an interface 802. That is, the processing module 601 can be implemented by the logic circuit 801, and the transceiver module 602 can be implemented by the interface 802. The logic circuit 801 can be a chip, a processing circuit, an integrated circuit or a system on chip (SoC) chip, etc., and the interface 802 can be a communication interface, an input / output interface, a pin, etc. For example, Figure 8 The above communication device is used as an example. The chip includes a logic circuit 801 and an interface 802 .

[0700] 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.

[0701] 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.

[0702] Exemplarily, the logic circuit 801 is used to generate a PPDU; and the interface 802 is used to output the PPDU.

[0703] In some 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.

[0704] The interface 802 is used to input the PPDU; the logic circuit 801 is used to perform channel estimation based on the LTF sequence.

[0705] 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, etc., reference can be made to the above-mentioned method embodiments and will not be described in detail here.

[0706] Exemplarily, the chip may further include a memory, which may be used to store the LTF sequence.

[0707] 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.

[0708] 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.

[0709] An embodiment of the present application further provides a communication system, which includes a first communication device and a second communication device. The description of the first communication device and the second communication device can be referred to above.

[0710] 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.

[0711] 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.

[0712] The present application also provides a computer-readable storage medium, in which computer codes are stored. When the computer codes are executed on a computer, the computer executes the operations and / or processes performed by the first communication device in the method provided in the present application.

[0713] The present application also provides a computer-readable storage medium, in which computer codes are stored. When the computer codes are executed on a computer, the computer executes the operations and / or processes performed by the second communication device in the method provided in the present application.

[0714] The present application also provides a computer program product, which includes a computer code or a computer program. When the computer code or the computer program runs on a computer, the operations and / or processing performed by the first communication device in the method provided by the present application are executed.

[0715] The present application also provides a computer program product, which includes a computer code or a computer program. When the computer code or the computer program runs on a computer, the operations and / or processing performed by the second communication device in the method provided by the present application are executed.

[0716] In the several embodiments provided in the present 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. There can be other division methods in actual implementation, 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 it can be an electrical, mechanical or other form of connection.

[0717] The modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place or distributed on 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.

[0718] In addition, each functional module in each embodiment of the present application can be integrated into a module processing module, or each module can exist physically separately, or two or more modules can be integrated into one module. The above integrated modules can be implemented in the form of hardware or software functional modules.

[0719] If the integrated module is implemented in the form of a software function 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 partly contributed 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 a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned readable storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk and other media that can store program code.

[0720] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope 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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