Two-antenna CSD sending method and device
By using a cyclic shifter to process the transmitted signal in the CSD transmission method of two-day lines, the problems of AGC performance degradation and synchronization error in Wifi products are solved, and the channel smoothing performance and the accuracy of channel impulse response are improved.
Patent Information
- Application Number
- CN202411806439.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-06
- Publication Date
- 2025-02-28
AI Technical Summary
In Wifi products, uncontrolled beamforming during two-antenna transmission results in degradation of AGC performance, poor synchronization error and channel smoothing performance.
In the CSD transmission method of the two-antenna, the first and second cyclic shifters are respectively used to shift the transmission signal, and the first and second shift signals are generated, and transmitted through the transmitter.
On the premise of ensuring AGC performance, the synchronization performance and channel smoothing performance are improved, and the accuracy of channel impulse response is improved.
Smart Images
Figure CN119544015A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of communication technology, and in particular to a CSD sending method and device for two antennas. Background Art
[0002] In Wi-Fi products, when two antennas are used to send a single stream, the signals transmitted by each antenna are identical, which results in an uncontrolled beamforming effect.
[0003] In order to avoid beamforming that is not conducive to reception, one method is to use two antennas to send signals of different frequencies. Antenna one sends odd-numbered subcarriers, that is, no energy is sent on even-numbered subcarriers, and antenna two is the opposite. However, because the Wifi protocol uses the short training field (STF) for automatic gain control (AGC), and the STF has only 12 subcarriers under the 20MHz bandwidth, if it is divided into two halves, each antenna will only send on 6 subcarriers. There are too few subcarriers, which cannot accurately reflect the energy level of the signal, thus affecting the AGC performance. Another method is to send signals through CSD transmission technology. One antenna sends normally, and the other antenna sends the same signal, but the signal is unidirectionally cyclically shifted, which results in a false first path being found when synchronizing using the local correlation method, causing synchronization errors; at the same time, the existence of CSD transmission technology also interferes with the judgment of the impulse response length of the channel, damaging the smoothing processing performance of channel estimation.
[0004] Therefore, how to ensure the performance of AGC while improving the synchronization performance and channel smoothing performance has become an urgent problem to be solved in this field. Summary of the invention
[0005] The present application provides a CSD sending method and device for two antennas, aiming to ensure the performance of AGC while improving the synchronization performance and channel smoothing performance.
[0006] In order to achieve the above objectives, this application provides the following technical solutions:
[0007] A CSD sending method for two antennas, comprising:
[0008] Acquire a first signal to be sent and a second signal to be sent; the first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal;
[0009] When the first signal to be sent is an STF signal, using a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal;
[0010] When the second signal to be sent is not the STF signal, using a second cyclic shifter to shift the second signal to be sent to obtain a second shifted signal;
[0011] A first antenna signal including the first shifted signal and a second antenna signal including the second shifted signal are transmitted using a transmitter.
[0012] Optionally, the using a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal includes:
[0013] Filtering a signal of a preset length from the end position of the first signal to be sent by a first cyclic shifter, and marking it as a first target signal;
[0014] The first target signal is shifted to a starting position of the first signal to be sent by the first cyclic shifter to obtain a first shifted signal.
[0015] Optionally, the using a second cyclic shifter to perform shift processing on the second signal to be sent to obtain a second shifted signal includes:
[0016] Using a second cyclic shifter to filter out a signal of a preset length from a starting position of the second signal to be sent, and marking it as a second target signal;
[0017] The second target signal is shifted to the end position of the second signal to be sent by using the second cyclic shifter to obtain a second shifted signal.
[0018] Optionally, also include:
[0019] When the second signal to be sent is an STF signal, the transmitter is used to send a second antenna signal including the second signal to be sent.
[0020] Optionally, also include:
[0021] When the first signal to be sent is not an STF signal, the transmitter is used to send a first antenna signal including the first signal to be sent.
[0022] A CSD transmitting device for two antennas, comprising:
[0023] An acquisition unit, configured to acquire a first signal to be sent and a second signal to be sent; the first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal;
[0024] a first shift unit, configured to, when the first signal to be sent is an STF signal, perform shift processing on the first signal to be sent using a first cyclic shifter to obtain a first shifted signal;
[0025] a second shift unit, configured to, when the second signal to be sent is not the STF signal, perform shift processing on the second signal to be sent by using a second cyclic shifter to obtain a second shifted signal;
[0026] The sending unit is configured to send, by using a transmitter, a first antenna signal including the first shifted signal and a second antenna signal including the second shifted signal.
[0027] Optionally, the first shifting unit is specifically used for:
[0028] Filtering a signal of a preset length from the end position of the first signal to be sent by a first cyclic shifter, and marking it as a first target signal;
[0029] The first target signal is shifted to a starting position of the first signal to be sent by the first cyclic shifter to obtain a first shifted signal.
[0030] Optionally, the second shift unit is specifically used for:
[0031] Using a second cyclic shifter to filter out a signal of a preset length from a starting position of the second signal to be sent, and marking it as a second target signal;
[0032] The second target signal is shifted to the end position of the second signal to be sent by using the second cyclic shifter to obtain a second shifted signal.
[0033] Optionally, also include:
[0034] The first signal sending unit is configured to use the transmitter to send a second antenna signal including the second signal to be sent when the second signal to be sent is an STF signal.
[0035] Optionally, also include:
[0036] The second signal sending unit is configured to use the transmitter to send a first antenna signal including the first signal to be sent.
[0037] The technical solution provided by the present application includes a first signal to be sent and a second signal to be sent; when the first signal to be sent is an STF signal, the first cyclic shifter is used to shift the first signal to be sent, the first shifted signal; when the second signal to be sent is not an STF signal, the second cyclic shifter is used to shift the second signal to be sent, the second shifted signal; and a transmitter is used to send a first antenna signal containing the first shifted signal and a second antenna signal containing the second shifted signal. Using different cyclic shifters to process the transmission signals of the two antennas respectively can improve the synchronization accuracy when synchronizing by correlating the received signal with the locally stored signal while ensuring the AGC performance, and can also obtain a more accurate channel impulse response to help obtain better channel smoothing performance. BRIEF DESCRIPTION OF THE DRAWINGS
[0038] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0039] Figure 1 A flowchart of a CSD sending method for two antennas provided in an embodiment of the present application;
[0040] Figure 2 A schematic diagram of a physical layer frame structure of an 802.11g signal provided in an embodiment of the present application;
[0041] Figure 3 A flowchart of a method for shifting a signal to be sent provided in an embodiment of the present application;
[0042] Figure 4 A flowchart of another method for shifting a signal to be sent provided in an embodiment of the present application;
[0043] Figure 5 A schematic diagram of an antenna signal provided in an embodiment of the present application;
[0044] Figure 6 A schematic diagram of the first path of an antenna provided in an embodiment of the present application;
[0045] Figure 7 A schematic diagram of the architecture of a CSD sending device for two antennas provided in an embodiment of the present application. DETAILED DESCRIPTION
[0046] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0047] In this application, the terms "comprises", "comprising" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprising a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element.
[0048] like Figure 1 FIG. 1 is a flowchart of a CSD sending method for two antennas provided in an embodiment of the present application, comprising the following steps:
[0049] S101: Acquire a first signal to be sent and a second signal to be sent.
[0050] The first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal.
[0051] It can be understood that the signal to be sent (ie, the first signal to be sent and the second signal to be sent) may also be an STF signal, an LTF signal or other time domain signals in the signal.
[0052] It should be noted that in the Wifi protocol, whether it is Wifi3 or later protocols, the beginning of the frame structure is the same. Taking 802.11g, i.e. Wifi3, as an example, 802.11g consists of a short training field (STF) and a long training field (LTF), etc. The specific physical layer frame structure is as follows: Figure 2 As shown, the signals are sent in chronological order, that is, the STF signal is sent first, and then the LTF signal and the subsequent time domain signals are sent.
[0053] For a 20MHz bandwidth, both STF and LTF have 160 sampling points in the time domain. STF is represented as s0 to s159. STF consists of 10 segments, each of which is the same and has 16 points. LTF consists of 3 segments. The last two segments are repeated signals, each with 64 points, represented as l0 to l63. The first segment is a cyclic prefix with a total of 32 points. It always repeats the last 32 points of the signal, so they are l32 to l63 respectively. The two antennas are named the first antenna and the second antenna.
[0054] Specifically, taking 802.11g signal as an example, for other Wi-Fi signals, the Legacy part (traditional 802.11g signal part, for the purpose of forward compatibility) is still the same as 802.11g, and only the Legacy part needs to add CSD according to the antenna, so only this section of the signal needs to be processed, which is obviously the same processing method as the 802.11g signal.
[0055] S102: When the first signal to be sent is an STF signal, use a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal.
[0056] When the first signal to be sent is an STF signal, the first signal to be sent is input into the first cyclic shifter, and the first signal to be sent is shifted by the first cyclic shifter. The first cyclic shifter circulates slightly to the right, that is, a small segment of the end signal is cyclically shifted to the beginning of the signal to be sent to achieve shift processing.
[0057] Optionally, in another embodiment of the present application, in step S102, the first cyclic shifter is used to perform shift processing on the first signal to be transmitted, and the specific implementation method of the first shifted signal is as follows: Figure 3 As shown, the following steps are included:
[0058] S301: Filter out a signal of a preset length from the end position of a first signal to be sent through a first cyclic shifter, and mark it as a first target signal.
[0059] Optionally, the preset length includes but is not limited to: 0.2us.
[0060] Specifically, assuming that the first signal to be sent is s0, s1, ..., s159, the signals of a preset length at the end position of the first signal to be sent are screened out by the first cyclic shifter as s156, s157, s158, s159, and s156, s157, s158, s159 are identified as the first target signals.
[0061] S302: Shift the first target signal to the starting position of the first signal to be sent through a first cyclic shifter to obtain a first shifted signal.
[0062] The first target signal is shifted to the starting position of the first signal to be sent through the first cyclic shifter, that is, when sending the first antenna signal, the first target signal is sent first, and then the remaining signal of the first antenna signal is sent.
[0063] Specifically, assuming that the first signal to be sent is s0, s1,…, s159, and the first target signal is s156, s157, s158, s159, the first target signal is shifted to the starting position of the first signal to be sent through a first cyclic shifter to obtain a first shifted signal of s156, s157, s158, s159, s0, s1,…, s155.
[0064] S103: When the second signal to be sent is not an STF signal, use a second cyclic shifter to perform shift processing on the second signal to be sent to obtain a second shifted signal.
[0065] When the second signal to be sent is not an STF signal, the second signal to be sent includes but is not limited to: an LTF signal, and other time domain signals after the LTF signal.
[0066] It should be noted that when the second signal to be sent is not an STF signal, the second signal to be sent is input into the second cyclic shifter, and the second signal to be sent is shifted by the second cyclic shifter. The second cyclic shifter circulates slightly to the left, that is, a small segment of the signal at the starting position is cyclically shifted to the end position of the second signal to be sent to achieve the shift processing.
[0067] Optionally, in another embodiment of the present application, in step S103, the second cyclic shifter is used to perform shift processing on the second signal to be transmitted. The specific implementation of the second shift signal is as follows: Figure 4 As shown, the following steps are included:
[0068] S401: Utilize a second cyclic shifter to filter out a signal of a preset length from a starting position of a second signal to be transmitted, and mark it as a second target signal.
[0069] Specifically, assuming that the second signal to be sent is an LTF signal, namely: l0, l1, l2, l3, ..., l63, the second cyclic shifter filters out signals of a preset length from the starting position of the second signal to be sent: l0, l1, l2, l3, and l0, l1, l2, l3 are identified as the second target signals.
[0070] S402: Using a second cyclic shifter, shift the second target signal to the end position of the second signal to be sent to obtain a second shifted signal.
[0071] The second target signal is shifted to the end position of the second signal to be sent by the second cyclic shifter. When the second antenna signal is subsequently sent, the signal other than the second target signal in the second antenna signal is sent first, and then the second target signal is sent.
[0072] Specifically, assuming that the second signal to be sent is an LTF signal, the second signal to be sent is: l0, l1, l2, l3, ..., l63, and the second target signal is: l0, l1, l2, l3. The last two segments of the LTF signal are cyclically shifted, that is, the second target signal is shifted to the end position of the second signal to be sent, and the second shifted signal is l4, l5, ..., l63, l0, l1, l2, l3. Since the first segment of the cyclic prefix signal in the LTF signal is based on the cyclic prefix rule (that is, the cyclic prefix is 32), it becomes l36, ..., l63, l0, l1, l2, l3.
[0073] It should be emphasized that for other time domain signals after the LTF signal, the cyclic prefix is 16 points instead of 32 points, but the rule is the same, and the last 16 points of the signal are always used as the cyclic prefix.
[0074] For example, the second signal to be sent is other time domain signals after the LTF signal, which are: d0, d1, d2, ..., d63. The last two signals in the LTF signal are cyclically shifted, that is, the second target signal is shifted to the end position of the second signal to be sent, and the second shifted signal is d2, d3, d4, d, ..., d63, d0, d1. Since the first cyclic prefix signal in other time domain signals after the LTF signal is based on the cyclic prefix rule (that is, the cyclic prefix is 16), it becomes d48, d49, d50, ..., d63, d0, d1.
[0075] S104: Utilize a transmitter to send a first antenna signal including a first shifted signal and a second antenna signal including a second shifted signal.
[0076] The first antenna signal containing the first shifted signal and the second antenna signal containing the second shifted signal are input into the transmitter, so that the transmitter transmits the first antenna signal containing the first shifted signal and the second antenna signal containing the second shifted signal through two antennas according to the Wifi protocol.
[0077] Specifically, assume that the two antenna signals after entering the transmitter are as follows Figure 5 As shown, for simplicity of explanation, only the STF signal and the first 4.8us of the LTF signal are shown, because the last 3.2us is repeated with the previous 3.2us and is therefore omitted.
[0078] Optionally, after step S104, there is a situation where the signal to be sent does not need to be shifted by a cyclic shifter, so another embodiment of the present application provides a method for sending a signal to be sent, including:
[0079] When the second signal to be sent is an STF signal, the transmitter is used to send a second antenna signal including the second signal to be sent.
[0080] It is understandable that when the second signal to be transmitted is an STF signal and the second signal to be transmitted is a signal of the second antenna, there is no need to perform shift processing on the second signal to be transmitted, and the transmitter can directly send the second antenna signal containing the second signal to be transmitted.
[0081] When the first signal to be sent is not an STF signal, a transmitter is used to send a first antenna signal including the first signal to be sent.
[0082] It can be understood that when the first signal to be sent is not an STF signal, there is no need to perform shift processing on the first signal to be sent.
[0083] In addition, after a first antenna signal including a first shifted signal and a second antenna signal including a second shifted signal are sent by a transmitter, they are transmitted to a receiver through multipath. When a first received signal sent by the first antenna and a second received signal sent by the second antenna are received, a local STF signal is used to perform correlation analysis on the first received signal and the second received signal to obtain a first peak value of the first received signal and a second peak value of the second received signal. Since the second peak value has not undergone cyclic shift, the second peak value is determined as the first path.
[0084] For example, see Figure 6 , Figure 6 The STF signals in the first antenna signal and the second antenna signal are shown in the figure. It can be seen that they are aligned in transmission time, but the STF signal in the first antenna signal has an additional cyclic shift relative to the second antenna signal. After receiving, the first antenna signal and the second antenna signal will be mixed together. Simply put, the first antenna signal and the second antenna signal are received, and the received signal and the local STF signal are correlated and analyzed. From a time perspective, the second peak value P1 obtained by s0~s15 of the second antenna is first, followed by the first peak value P2 obtained by s0~s15 of the first antenna. P1 is the first peak value obtained without cyclic shift, that is, the first path.
[0085] Secondly, the local LTF signal is used to perform correlation analysis on the first received signal and the second received signal to obtain the fourth peak value Q2 of the first received signal and the third peak value Q1 of the second received signal; according to the correlation characteristics and multipath characteristics, the first path must be located at the end position of STF and LTF, and the cyclic prefix between the STF and LTF signals is 1.6us. Obviously, the received signals that generate P1 and Q2 have an integer number of 0.8us intervals in time, that is, an integer number of STF data segments plus 1 LTF cyclic prefix. Therefore, based on P1 being the first path, the receiver can determine that Q2 is also the first path, then Q1 must be a false first path, which can only be caused by the CSD sending technology.
[0086] It is understandable that the STF signal in the second antenna signal and the LTF signal in the first antenna have not been cyclically shifted, and the first peak they obtain is the first path. The two peaks are separated by the cyclic prefix of n STF segments and 1 LTF segment, that is, n*0.8us+1.6us=(n+2)*0.8us, so they are separated by an integer number of 0.8us. Since P1 is the first path obtained by the STF signal, and for the LTF signal, since the LTF in the second antenna signal is forward cyclic, the fourth peak Q1 in the second antenna signal will be obtained first when the correlation analysis is performed on the received signal. This is not the first path we want. Only the third peak Q2 and P1 of the first received signal just meet the condition that the two first paths are separated by an integer number of 0.8us mentioned above, which is the true first path.
[0087] From the above content, it can be seen that the signals from different transmitting antennas will experience almost the same length of multipath delay. Therefore, when calculating the channel impulse response length, we can directly count from Q2, which is 0.2us shorter than counting from Q1. Finally, when estimating the channel coherence bandwidth, we can get a coherence bandwidth closer to the actual one, which is larger than the coherence bandwidth estimated from Q1. Therefore, when smoothing the channel, more adjacent subcarriers can be used for smoothing, and the performance is improved.
[0088] In summary, using different cyclic shifters to process the transmit signals of the two antennas respectively can improve the synchronization accuracy when synchronizing by correlating the received signal with the local stored signal while ensuring the AGC performance, and at the same time can obtain a more accurate channel impulse response to help obtain better channel smoothing performance.
[0089] like Figure 7 , which is a schematic diagram of the architecture of a CSD sending device for two antennas provided in an embodiment of the present application, the CSD sending device includes: an acquisition unit 100, a first shift unit 200, a second shift unit 300 and a sending unit 400.
[0090] The acquisition unit 100 is used to acquire a first signal to be sent and a second signal to be sent; the first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal.
[0091] The first shift unit 200 is used for, when the first signal to be sent is an STF signal, using a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal.
[0092] The first shift unit 200 is specifically used to: filter out a signal of a preset length from the end position of the first signal to be sent through a first circular shifter, and mark it as a first target signal; shift the first target signal to the starting position of the first signal to be sent through the first circular shifter to obtain a first shifted signal.
[0093] The second shift unit 300 is used for, when the second signal to be sent is not an STF signal, performing shift processing on the second signal to be sent by using a second cyclic shifter to obtain a second shifted signal.
[0094] The second shift unit 300 is specifically used to: use the second circular shifter to filter out a signal of a preset length from the starting position of the second signal to be sent, and mark it as the second target signal; use the second circular shifter to shift the second target signal to the end position of the second signal to be sent to obtain a second shifted signal.
[0095] The sending unit 400 is configured to send, by using a transmitter, a first antenna signal including a first shifted signal and a second antenna signal including a second shifted signal.
[0096] In summary, using different cyclic shifters to process the transmit signals of the two antennas respectively can improve the synchronization accuracy when synchronizing by correlating the received signal with the local stored signal while ensuring the AGC performance, and at the same time can obtain a more accurate channel impulse response to help obtain better channel smoothing performance.
[0097] Preferably, combined Figure 7 According to the content shown, the CSD sending device also includes: a first signal sending unit, which is used to use a transmitter to send a second antenna signal containing the second signal to be sent when the second signal to be sent is an STF signal.
[0098] Preferably, combined Figure 7 As shown in the content, the CSD sending device also includes: a second signal sending unit, which is used to use a transmitter to send a first antenna signal containing the first signal to be sent when the first signal to be sent is not an STF signal.
[0099] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can refer to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the system or system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can refer to the partial description of the method embodiment. The system and system embodiments described above are merely schematic, wherein the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they may be located in one place, or they may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the scheme of this embodiment. Ordinary technicians in this field can understand and implement it without paying creative work.
[0100] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in the above description according to function. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.
[0101] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. A CSD transmission method for two antennas, characterized in that: include: Acquire a first signal to be sent and a second signal to be sent; the first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal; When the first signal to be sent is an STF signal, using a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal; When the second signal to be sent is not the STF signal, using a second cyclic shifter to shift the second signal to be sent to obtain a second shifted signal; A first antenna signal including the first shifted signal and a second antenna signal including the second shifted signal are transmitted using a transmitter.
2. The method according to claim 1, characterized in that The using a first cyclic shifter to perform shift processing on the first signal to be sent to obtain a first shifted signal includes: Filtering a signal of a preset length from the end position of the first signal to be sent by a first cyclic shifter, and marking it as a first target signal; The first target signal is shifted to a starting position of the first signal to be sent by the first cyclic shifter to obtain a first shifted signal.
3. The method according to claim 1, characterized in that The using a second cyclic shifter to perform shift processing on the second signal to be sent to obtain a second shifted signal includes: Using a second cyclic shifter to filter out a signal of a preset length from a starting position of the second signal to be sent, and marking it as a second target signal; The second target signal is shifted to the end position of the second signal to be sent by using the second cyclic shifter to obtain a second shifted signal.
4. The method according to claim 1, characterized in that: Also includes: When the second signal to be sent is an STF signal, the transmitter is used to send a second antenna signal including the second signal to be sent.
5. The method according to claim 1, characterized in that Also includes: When the first signal to be sent is not an STF signal, the transmitter is used to send a first antenna signal including the first signal to be sent.
6. A CSD transmitting device for two antennas, characterized in that: include: An acquisition unit, configured to acquire a first signal to be sent and a second signal to be sent; The first signal to be sent is a signal in the first antenna signal, and the second signal to be sent is a signal in the second antenna signal; a first shift unit, configured to, when the first signal to be sent is an STF signal, perform shift processing on the first signal to be sent using a first cyclic shifter to obtain a first shifted signal; a second shift unit, configured to, when the second signal to be sent is not the STF signal, perform shift processing on the second signal to be sent by using a second cyclic shifter to obtain a second shifted signal; The sending unit is configured to send, by using a transmitter, a first antenna signal including the first shifted signal and a second antenna signal including the second shifted signal.
7. The device according to claim 6, characterized in that The first shifting unit is specifically used for: Filtering a signal of a preset length from the end position of the first signal to be sent by a first cyclic shifter, and marking it as a first target signal; The first target signal is shifted to a starting position of the first signal to be sent by the first cyclic shifter to obtain a first shifted signal.
8. The device according to claim 6, characterized in that The second shifting unit is specifically used for: Using a second cyclic shifter to filter out a signal of a preset length from a starting position of the second signal to be sent, and marking it as a second target signal; The second target signal is shifted to the end position of the second signal to be sent by using the second cyclic shifter to obtain a second shifted signal.
9. The device according to claim 6, characterized in that Also includes: The first signal sending unit is configured to use the transmitter to send a second antenna signal including the second signal to be sent when the second signal to be sent is an STF signal.
10. The device according to claim 6, characterized in that Also includes: The second signal sending unit is configured to use the transmitter to send a first antenna signal including the first signal to be sent when the first signal to be sent is not an STF signal.