CN106162703B - A kind of wireless lan communication system for ranging and range rate - Google Patents

Abstract

The present invention is applicable to the field of communication technology, and provides a wireless local area network communication system for distance measurement and speed measurement. The system supports multiple input and output, configures a coupler for the transmitter of the first transceiver module, and provides a The receiver mixer configuration switch of the second transceiver module; when the switch in the receiver of the second transceiver module works in the first state, the first transceiver module and the second transceiver module work in the communication mode; When the switch in the receiver of the second transceiver module works in the second state, the first transceiver module and the second transceiver module work in the ranging and speed measurement mode; in the ranging and speed measurement mode, at the same time Realize the transmission and reception of ranging and speed measurement signals. The invention has little modification to the original wireless local area network communication system, is easy to implement, realizes the functions of distance measurement and speed measurement of the same frequency duplex transmission and reception, and ensures the accuracy of distance measurement and speed measurement.

Description

A wireless local area network communication system for distance measurement and speed measurement

technical field

The invention belongs to the field of communication technology, and in particular relates to a wireless local area network communication system for distance measurement and speed measurement.

Background technique

At present, wireless local area network communication technology has been widely used in various fields. A wireless local area network is a network constructed through routers that provides access point-based connectivity to the Internet and network devices. In addition, there is also a wireless point-to-point communication (Point-to-Point, P2P) that does not require a wireless network access point at present. The common standard of wireless local area network is 802.11, which is a standard for wireless network communication defined by the International Institute of Electrical and Electronic Engineering (IEEE). 802.11n and 802.11ac in the GHz and 5GHz bands, and 802.11ad in the 60GHz band, and in the wireless access scenario in the automotive environment, 802.11a and 802.11p in the 5GHz band are commonly used.

With the development of wireless local area network communication technology, wireless positioning technology also has application space. Through wireless positioning technology, intelligent collision avoidance between moving objects can be achieved. For example, by measuring distances between moving objects such as autonomous or driverless cars, drones or robots, collisions can be avoided during movement. However, in the wireless LAN communication of the 802.11 standard, the same frequency is used for the transmission and reception of signals, which makes it impossible to transmit and receive signals at the same time. The method of signal strength, signal arrival time and signal arrival angle has poor measurement accuracy, with an error of about 1 meter, and the ranging and speed measurement signals are susceptible to interference, which limits their practicality.

SUMMARY OF THE INVENTION

In view of this, the embodiments of the present invention provide a wireless local area network communication system for distance measurement and speed measurement, so as to solve the problem of poor measurement accuracy of the existing wireless distance measurement and speed measurement technology.

An embodiment of the present invention provides a wireless local area network communication system for distance measurement and speed measurement. The system supports multiple input and output and includes at least a first transceiver module and a second transceiver module, characterized in that the first transceiver module is the first transceiver module. The transmitter configures a coupler, and configures a switch for the receiver mixer of the second transceiver module;

When the switch in the receiver of the second transceiver module works in the first state, the first transceiver module and the second transceiver module work in the communication mode;

When the switch in the receiver of the second transceiver module works in the second state, the first transceiver module and the second transceiver module work in the ranging and speed measurement mode;

In the ranging and speed measurement mode, a part of the signal transmitted by the first transceiver module is transmitted through a transmitting antenna, and the rest is coupled to the second transceiver module through a coupler, and received with the second transceiver module The received reflected signal is mixed to realize the transmission and reception of ranging and speed measurement signals at the same time.

Further, the distance measuring and speed measuring signal includes a continuous wave signal or a continuous wave frequency modulation signal.

Further, the single-frequency operation of the system includes:

The first transceiver module and the second transceiver module work at 2.4GHz simultaneously; or,

The first transceiver module and the second transceiver module work at 5GHz at the same time.

Further, the system switches between the communication mode and the ranging and speed measurement mode according to the distance measurement and speed measurement results.

Further, according to the result of ranging and speed measurement, the system switching between the communication mode and the ranging and speed measurement mode includes:

making the first transceiver module and the second transceiver module work in the ranging and speed measurement mode;

When a preset switching condition is met, the first transceiver module and the second transceiver module are switched to the communication mode, and relevant information about the current ranging and speed measurement result is sent;

After completing the sending of the relevant information, the first transceiver module and the second transceiver module are switched back to the ranging and speed measuring mode.

Further, when a preset switching condition is met, switching the first transceiver module and the second transceiver module to the communication mode includes:

If the test distance in the current distance measurement and speed measurement result is within a preset first distance value interval, switch the first transceiver module and the second transceiver module to the communication mode; or

If the test speed in the current ranging and speed measurement result is less than or equal to 0, and the test distance in the current ranging and speed measurement result is within the preset second distance value interval, the first transceiver module and the The second transceiver module switches to the communication mode.

Further, the system operates in dual frequency, and further includes a third transceiver module and a fourth transceiver module, a coupler is configured for the transmitter of the third transceiver module, and a receiver mixer of the fourth transceiver module is configured. configuration switch;

The first transceiver module and the second transceiver module work at 2.4GHz simultaneously, and the third transceiver module and the fourth transceiver module work at 5GHz at the same time.

Further, the switch in the receiver of the second transceiver module works in the first state, and the switch in the receiver of the fourth transceiver module works in the second state, so that the first transceiver The module and the second transceiver module work in a communication mode, and the third transceiver module and the fourth transceiver module work in a ranging and speed measurement mode; or,

The switch in the receiver of the second transceiving module works in the second state, and the switch in the receiver of the fourth transceiving module works in the first state, so that the first transceiving module and the The second transceiver module works in a ranging and speed measurement mode, and the third transceiver module and the fourth transceiver module work in a communication mode; or,

The switches in the receivers of the second transceiving module and the fourth transceiving module work in the first state, so that the first transceiving module, the second transceiving module, and the third transceiving module Both the module and the fourth transceiver module work in a communication mode.

Further, make the switch in the receiver of the second transceiver module work in the second state, and the switch in the receiver of the fourth transceiver module work in the first state, so as to obtain the first ranging and speed measurement result;

If the test distance in the first distance measurement and speed measurement result is smaller than the preset distance threshold, the switch in the receiver of the second transceiver module is set to work in the first state, and the receiver of the fourth transceiver module is set to work in the first state. The switches in are operated in the second state.

Further, if the first transceiver module and the second transceiver module work in the communication mode, and the third transceiver module and the fourth transceiver module work in the ranging and speed measurement mode, the first transceiver The module and the second transceiver module send the current ranging and speed measurement results in real time;

If the first transceiving module and the second transceiving module work in the ranging and speed measurement mode, and the third transceiving module and the fourth transceiving module work in the communication mode, the third transceiving module and the The fourth transceiver module sends the current ranging and speed measurement results in real time.

The wireless local area network communication system for distance measurement and speed measurement provided by the embodiment of the present invention can realize automatic driving or independent communication between unmanned vehicles and unmanned aerial vehicles to avoid collision. The communication system has a small transformation and is easy to implement. The distance measurement and speed measurement functions of the same frequency duplex transmission and reception are truly realized in different transceiver modules of the wireless system, and the accuracy of distance measurement and speed measurement is guaranteed.

Description of drawings

In order to illustrate the technical solutions in the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only for the present invention. In some embodiments, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

1 is a flowchart of system baseband signal processing for communication and ranging and speed measurement in a transceiver module for receiving provided by an embodiment of the present invention;

2 is a system structure diagram of a wireless local area network communication system provided by an embodiment of the present invention when a single frequency operates;

3 is a flowchart of switching between the communication mode and the ranging and speed measurement mode when the wireless local area network communication system provided by an embodiment of the present invention operates on a single frequency;

4 is a specific implementation example diagram of switching between a communication mode and a ranging and speed measurement mode in a wireless local area network communication system in a ranging and speed measurement process provided by an embodiment of the present invention;

FIG. 5 is a system structure diagram of a wireless local area network communication system provided by an embodiment of the present invention during dual-frequency operation;

Fig. 6 is a specific implementation example diagram of dual-frequency operation of the wireless local area network communication system in the process of distance measurement and speed measurement provided by an embodiment of the present invention;

7 is a schematic diagram of the states of a 2.4GHz ranging and speed measurement coarse mode and a 5GHz communication mode provided by an embodiment of the present invention;

8 is a schematic diagram of the states of a 5GHz ranging and speed measurement fine mode and a 2.4GHz communication mode provided by an embodiment of the present invention;

9 is a schematic diagram of a communication mode of a multi-input multi-output dual-frequency multi-transceiver module provided by an embodiment of the present invention;

FIG. 10 is an example diagram of an application of a wireless local area network communication system for distance measurement and speed measurement provided by an embodiment of the present invention.

Detailed ways

In the following description, for the purpose of illustration rather than limitation, specific details such as specific system structures and technologies are set forth in order to provide a thorough understanding of the embodiments of the present invention. However, it will be apparent to those skilled in the art that the present invention may be practiced in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present invention with unnecessary detail.

In the embodiment of the present invention, a wireless local area network communication system for distance measurement and speed measurement supports multiple input and output (Multiple-Input Multiple-Output, MIMO), and at least includes a first transceiver module and a second transceiver module, which are the first transceiver module. The transmitter of the module configures a coupler, and configures a switch for the receiver mixer of the second transceiver module; when the switch in the receiver of the second transceiver module works in the first state, the first transceiver The module and the second transceiver module work in the communication mode; when the switch in the receiver of the second transceiver module works in the second state, the first transceiver module and the second transceiver module work in ranging Speed measurement mode; in the distance measurement and speed measurement mode, a part of the signal transmitted by the first transceiver module is transmitted through a transmitting antenna, and the rest is coupled to the second transceiver module through a coupler, and communicates with the second transceiver module. The reflected signals received by the transceiver module are mixed to simultaneously transmit and receive the ranging and speed measuring signals.

Based on the above description of the wireless local area network communication system for distance measurement and speed measurement provided by the embodiment of the present invention, in the embodiment of the present invention, the first transceiver module and the second transceiver module have the same frequency and have the same module structure, and the system can work Under the communication mode and the ranging and speed measurement mode. For the communication mode, it is the same as the implementation in the prior art. For ranging and speed measurement mode, its working principle is to couple the transmit signal of one transceiver module to the receive signal of another transceiver module with the same frequency, and get the difference frequency signal after mixing by the mixer, and then low-pass filtering. Finally, Fourier transform is performed in the digital domain to obtain frequency and phase information, so as to calculate the distance and speed according to the frequency and phase information. For the communication mode and the ranging and speed measurement mode, the biggest difference between the system operation is the receiving end of the signal. In the communication mode, the receiving end converts the radio frequency signal into a baseband signal through the local oscillator, and the baseband signal passes through the analog-to-digital converter. Digital domain demodulation finally obtains a digital signal; while in the ranging and speed measurement mode, the transmitted signal and the received signal are directly mixed, and the local oscillator is no longer required. Therefore, when the first transceiver module and the second transceiver module work in the ranging and speed measurement mode, the switch in the receiver of the second transceiver module will select the signal coupled from the transmission signal of the first transceiver module and the second transceiver module. The signal reflected from the test object received by the transceiver module is mixed.

In the embodiment of the present invention, the selection of the operation mode of the switch in the receiver depends on the type of the transmitted signal. In the communication mode, the transmitter will transmit various modulation signals, such as quadrature amplitude modulation signal or phase shift keying modulation signal, while in the ranging and speed measurement mode, the transmitter transmits multiple continuous wave signals (Continuous-Wave CW ) or a continuous wave frequency modulation signal (Frequency-Modulated Continuous-Wave FMCW), and the current wireless local area network communication system has also supported the transmission of continuous wave signals or continuous wave frequency modulation signals. Therefore, the embodiment of the present invention can be used in existing It is obtained by transforming on the basis of the wireless local area network communication system. In addition, for the continuous wave signal, it can be used in short-range ranging and speed measurement, and multiple continuous waves refer to continuous waves with more than two frequencies, and the frequency of the continuous wave can be selected by the user within a certain range. The working principle of continuous wave signal ranging is to calculate the distance to the test object by comparing the phase difference between the transmitted signal and the received signal. For example, if the frequencies of two continuous waves are 5180MHz and 5190MHz respectively, and the frequency separation is 10MHz, the maximum measurable distance is 15 meters. The minimum accuracy is determined by the phase accuracy of the wireless local area network communication system. In the embodiment of the present invention, an in-phase quadrature mixer is used as the phase detector. If the phase accuracy of the system is set to be 1.2 degrees, the measurement accuracy can reach 0.05 meters. If the frequency interval of the two continuous waves is 20MHz, the same phase accuracy is maintained, the maximum measurable distance is 7.5 meters, and the measurement accuracy can reach 0.025 meters. For the continuous wave frequency modulation signal, it can be used in long-distance ranging and speed measurement. The working principle of its ranging is to calculate the distance through the difference frequency of the transmitted signal and the received signal. The distance resolution of the continuous wave frequency modulation signal is determined by the bandwidth of the signal. If the continuous wave frequency modulation signal is from frequency 2300MHz to frequency 2500MHz, that is, the bandwidth is 200MHz, the corresponding distance resolution is 0.75 meters; if the continuous wave frequency modulation signal It is from the frequency 5250MHz to the frequency 5925MHz, that is, the bandwidth is 675MHz, and the corresponding distance resolution is 0.22 meters. It can be seen that, compared with 2.4GHz, using 5GHz in-band signal, the system can achieve a better effect of ranging and speed measurement. The working principle of the speed measurement of multiple continuous wave signals or continuous wave frequency modulation signals is obtained by measuring the Doppler frequency. Within a distance of 15 meters, using multiple continuous wave signals or continuous wave frequency modulation signals at the same time, the measurement accuracy can reach 0.05 meters or even higher. In the transceiver module for receiving, the system baseband signal processing flow for communication and ranging and speed measurement is shown in Figure 1. In the communication mode, the communication modulated signal transmitted by the transmitter of the transceiver module is processed by the receiver of the transceiver module. Demodulate to obtain data such as pictures and sounds; in the range and speed measurement mode, the continuous wave frequency modulation signal transmitted by the transmitter of the transceiver module calculates the distance and speed through Fourier transform under the receiver of another transceiver module, and the transmitter of the transceiver module calculates the distance and speed. The transmitted multiple continuous wave signals calculate the distance through the phase detection of the in-phase quadrature mixer under the receiver of another transceiver module. In addition, in the ranging and speed measurement mode, the transceiver module as the transmitter needs to transmit a synchronization signal to another transceiver module as the receiver.

In the embodiment of the present invention, the wireless local area network communication system supports working under single frequency or dual frequency. Next, the situation of single-frequency operation is first elaborated:

When the wireless local area network communication system operates on a single frequency, the first transceiver module and the second transceiver module simultaneously operate at 2.4 GHz; or, the first transceiver module and the second transceiver module simultaneously operate at 5 GHz. That is, one transceiver module works at 2.4GHz for signal transmission, and the other transceiver module also works at 2.4GHz for signal reception; alternatively, one transceiver module works at 5GHz for signal transmission, and the other transceiver module also works at 5GHz for signal reception.

FIG. 2 shows a system structure diagram of the wireless local area network communication system when a single frequency is used, wherein the transceiver module 40 and the transceiver module 41 can both work at 2.4GHz or 5GHz. In FIG. 2 , the solid line part is the structure of the existing wireless local area network communication system, and the dotted line part is the transformation based on the existing wireless local area network communication upgrade to the structure according to the embodiment of the present invention. In the communication mode, the transceiver module 40 and the transceiver module 41 can transmit or receive signals at the same time, or one can transmit signals and the other can receive signals, but in the ranging and speed measurement mode, there can only be one transceiver module 40 and one transceiver module 41 One for signal transmission and the other for signal reception. In the communication mode, the transceiver module 40 and the transceiver module 41 use the same system structure. At the transmitting end, the signal modulated by the baseband 1 passes through the in-phase digital-to-analog converter 2 and the quadrature digital-to-analog converter 3, and then passes through the non-inverting amplifier 10 and the positive The AC amplifier 11 reaches the carrier amplifier 30 through the in-phase mixer 20, the quadrature mixer 21 and the local oscillator 18, and the obtained carrier signal passes through the radio frequency switch 36 and is transmitted through the antenna 38; at the receiving end, the received signals are sequentially Through the antenna 38, the radio frequency switch 36 and the low noise amplifier 31, after mixing by the in-phase mixer 22, the quadrature mixer 23 and the local oscillator 18, and then through the in-phase amplifier 12 and the quadrature amplifier 13, through the in-phase digital-analog The converter 4 and the quadrature digital-to-analog converter 5 perform demodulation and signal processing at the baseband 1 . In the ranging and speed measurement mode, one of the transceiver module 40 and the transceiver module 41 works in a transmitting state, and the other works in a receiving state. If the transceiver module 40 is used as the transmitting end, a plurality of continuous waves or continuous wave frequency modulation signals are transmitted, and a part of the transmitted signals will be coupled to the receiving end of the transceiver module 41 . At the same time, the signal received by the transceiver module 41 will pass through the antenna 39, the radio frequency switch 37 and the low noise amplifier 33, and then through the switch 29, the transmission signal of the transceiver module 40 coupled by the coupler 34 and the in-phase mixer 27 and the quadrature After mixing by the mixer 28, it enters the in-phase low-noise amplifier 16 and the quadrature low-noise amplifier 17, and finally passes through the in-phase analog-to-digital converter 8 and the quadrature analog-to-digital converter 9, and performs phase detection and Fourier transform at the baseband 1 to obtain Phase and frequency information. Conversely, if the transceiver module 41 is used as the transmitting end and the transceiver module 40 is used as the receiving end, the transceiver module 41 transmits multiple CW or CW frequency modulation signals, and some of the transmitted signals are coupled to the receiving end of the transceiver module 40 . At the same time, the signal received by the transceiver module 40 will pass through the antenna 38, the radio frequency switch 36 and the low noise amplifier 31, and then through the switch 24 to couple the coupler 35 to the transmit signal of the transceiver module 41 and the in-phase mixer 22 and the quadrature mixer. After mixing by the frequency converter 23, it enters the in-phase low-noise amplifier 12 and the quadrature low-noise amplifier 13, and finally passes through the in-phase analog-to-digital converter 4 and the quadrature analog-to-digital converter 5, and performs phase detection and Fourier transform at the baseband 1 to obtain the phase and frequency information.

In this embodiment of the present invention, the communication mode and the ranging and speed measurement mode share a baseband radio frequency circuit and an antenna in a time division duplex (TDD) manner, and preferably, according to the distance measurement and speed measurement results, the communication mode and the Switch between ranging and speed measurement modes. The above switching can be used to transmit the results of ranging and speed measurement in the process of ranging and speed measurement. As shown in FIG. 3 , the system switches between the communication mode and the range and speed measurement mode according to the results of ranging and speed measurement. Toggles include:

S301. Make the first transceiver module and the second transceiver module work in the ranging and speed measuring mode.

S302 , when a preset switching condition is satisfied, switch the first transceiver module and the second transceiver module to the communication mode, and send relevant information about the current ranging and speed measurement results.

S303, after completing the sending of the relevant information, switch the first transceiver module and the second transceiver module back to the ranging and speed measuring mode.

It can be seen from the embodiment corresponding to FIG. 3 that the wireless local area network communication system mainly works in the ranging and speed measurement mode. By setting switching conditions, it is used as a condition for judging whether the current ranging and speed measurement results need to be reported. When the preset switching conditions are used, the wireless LAN communication system briefly switches to the communication mode, and sends relevant information about the current ranging and speed measurement results, such as collision avoidance warning, information broadcasting, cruise control, power control, etc., and completes the information transmission. After sending, switch back to the ranging and speed measurement mode, and continue to perform ranging and speed measurement.

Preferably, for the implementation of S302, the following algorithm ideas can be followed:

If the test distance in the current distance measurement and speed measurement result is within a preset first distance value interval, switch the first transceiver module and the second transceiver module to the communication mode; or

If the test speed in the current ranging and speed measurement result is less than or equal to 0, and the test distance in the current ranging and speed measurement result is within the preset second distance value interval, the first transceiver module and the The second transceiver module switches to the communication mode.

Based on the embodiment corresponding to FIG. 3 , FIG. 4 shows that the wireless local area network communication system switches between the communication mode and the ranging and speed measurement mode in the process of distance measurement and speed measurement, so as to realize the result of distance measurement and speed measurement at the same time as distance measurement and speed measurement. A specific implementation example for notification:

In Fig. 4, the judgment conditions of distance speed and time can be adjusted and changed according to the design and environment of the system. Figure 4 shows that the system first enters the rough mode of continuous wave frequency modulation signal ranging and speed measurement, and the obtained distance and speed will be stored in the memory for power control, cruise intelligent system and ranging and speed measurement result notification. The system will determine whether to switch to the communication mode at the next moment or maintain the distance measurement and speed measurement mode according to the distance. If the test distance in the current ranging and speed measurement results is greater than 100 meters and less than 1 km, the system enters the communication mode, and the system can communicate point-to-point with external individuals, or conduct network communication through the access point to obtain external environment information or self-information broadcast. The working time of the system in the communication mode will not exceed 2 milliseconds, otherwise the system will automatically switch to the precision ranging and speed measurement mode. If the test distance in the current ranging and speed measurement results is less than 100 meters, the system enters the ranging and speed measurement accuracy mode, and multiple continuous wave and continuous wave frequency modulation signals will alternately measure the precise distance and speed. Similarly, the obtained distance and speed The speed is stored in memory. After that, the working mode of the system is determined by the test speed in the current ranging and speed measurement results. If the test speed is less than zero, the object is moving in the direction of the terminal where the system is located, and the system still works in the precision ranging and speed measurement mode; if the test speed is greater than Zero, the object is moving against the direction of the terminal where the system is located, and the system will switch to the rough mode of ranging and speed measurement. After making a judgment based on the test speed, the system will further judge the distance. If the test distance in the current ranging and speed measurement results is greater than 5 meters and less than 100 meters, the system still works in the precision ranging and speed measurement mode, and the system is in the precision ranging and speed measurement mode. The time of the mode will not exceed 0.2 milliseconds, otherwise the system will automatically switch to the communication mode; if the test distance in the current ranging and speed measurement results is less than 5 meters, the system will automatically switch to the early warning state.

Next, the situation of dual-frequency operation is explained in detail:

When the wireless local area network communication system works in dual frequency, it also includes a third transceiver module and a fourth transceiver module, a coupler is configured for the transmitter of the third transceiver module, and a receiver mixer is configured for the fourth transceiver module. A configuration switch; the first transceiver module and the second transceiver module work at 2.4GHz simultaneously, and the third transceiver module and the fourth transceiver module work at 5GHz at the same time.

When the wireless local area network communication system works with dual frequencies, specifically, the following situations may occur:

The switch in the receiver of the second transceiving module works in the first state, and the switch in the receiver of the fourth transceiving module works in the second state, so that the first transceiving module and the The second transceiver module works in a communication mode, and the third transceiver module and the fourth transceiver module work in a ranging and speed measurement mode; or,

The switch in the receiver of the second transceiving module works in the second state, and the switch in the receiver of the fourth transceiving module works in the first state, so that the first transceiving module and the The second transceiver module works in a ranging and speed measurement mode, and the third transceiver module and the fourth transceiver module work in a communication mode; or,

The switches in the receivers of the second transceiving module and the fourth transceiving module work in the first state, so that the first transceiving module, the second transceiving module, and the third transceiving module Both the module and the fourth transceiver module work in a communication mode.

Figure 5 shows a system structure diagram of the wireless local area network communication system when dual-frequency operation is performed. In Figure 5, the transceiver module 95 and the transceiver module 97 work at 2.4GHz, and the transceiver module 96 and the transceiver module 98 work at 5GHz. In FIG. 5 , the solid line part is the structure of the existing wireless local area network communication system, and the dotted line part is the transformation based on the upgrade of the existing wireless local area network communication to the structure according to the embodiment of the present invention. The biggest difference between FIG. 5 and FIG. 2 is that the antenna separation filter 61 , the antenna separation filter 83 , the dual-band antenna 62 and the dual-band antenna 84 in FIG. 5 work at two frequencies of 2.4 GHz and 5 GHz. The structure of FIG. 5 It can realize the simultaneous operation of communication mode and ranging and speed measurement mode. When the transceiver module 95 and the transceiver module 97 work in the 2.4GHz communication mode, the transceiver module 96 and the transceiver module 98 work in the 5GHz ranging and speed measurement mode; on the contrary, when the transceiver module 96 and the transceiver module 98 work in the 2.4GHz communication mode , the transceiver module 95 and the transceiver module 97 work in the 5GHz ranging and speed measuring mode, which realizes the support for the communication mode and the ranging and speed measuring mode at the same time, and provides real communication and ranging and speed measuring functions. The working principle of the distance measuring and speed measuring mode here is consistent with the working principle described above. In addition, the transceiver module 95 and the transceiver module 97 of 2.4GHz, and the transceiver module 96 and the transceiver module 98 of 5GHz can all work in the communication mode at the same time.

As mentioned above, compared with 2.4GHz, the system can achieve better range and speed measurement effect by using 5GHz in-band signal. Therefore, as an embodiment of the present invention, the 2.4GHz range and speed measurement mode can be used first, Until the test distance of the current ranging and speed measurement results is small, the 5GHz ranging and speed measurement mode is used to ensure the accuracy of the ranging and speed measurement. specifically:

Make the switch in the receiver of the second transceiver module work in the second state, and the switch in the receiver of the fourth transceiver module work in the first state, to obtain a first ranging and speed measurement result;

If the test distance in the first distance measurement and speed measurement result is smaller than the preset distance threshold, the switch in the receiver of the second transceiver module is set to work in the first state, and the receiver of the fourth transceiver module is set to work in the first state. The switches in are operated in the second state.

In addition, since the dual-frequency wireless local area network communication system can support the communication mode and the ranging and speed measurement mode at the same time, the distance measurement and speed measurement results can be sent at the same time, specifically:

If the first transceiver module and the second transceiver module work in the communication mode, and the third transceiver module and the fourth transceiver module work in the ranging and speed measurement mode, the first transceiver module and the The second transceiver module sends the current ranging and speed measurement results in real time;

If the first transceiving module and the second transceiving module work in the ranging and speed measurement mode, and the third transceiving module and the fourth transceiving module work in the communication mode, the third transceiving module and the The fourth transceiver module sends the current ranging and speed measurement results in real time.

Figure 6 shows a specific implementation example of the operation of the wireless local area network communication system with dual-frequency operation:

In Fig. 6, the judgment conditions of distance speed and time can also be adjusted and changed according to the design and environment of the system. Figure 6 shows that the system first enters the 2.4GHz ranging and speed-measuring coarse mode and 5GHz communication mode. The test distance and test speed obtained in the 2.4GHz ranging and speed-measuring coarse mode will be stored in the memory for power control, cruise intelligent system and measurement Announcement of speed measurement results. As shown in Figure 7, the 2.4GHz ranging and speed measurement coarse mode and 5GHz communication mode have eight dual-frequency coexistence states or six single-frequency states, and the system can only work in one of the eight dual-frequency coexistence states or six single-frequency states. One. The 5GHz communication mode can communicate with external individuals point-to-point, or through network communication through access points to obtain external environmental information or broadcast self-information. The system will judge whether the next moment is still the coexistence of ranging and speed measuring coarse/fine mode and communication mode according to the distance. If the test distance in the current ranging and speed measurement results is less than 500 meters, the system enters the 5GHz ranging and speed measurement fine mode and the 2.4GHz communication mode. Get external environmental information or broadcast self-information. As shown in Figure 8, the 5GHz ranging and speed measurement fine mode and 2.4GHz communication mode also have eight dual-frequency coexistence states or six single-frequency states, and the system can only work in one of the eight dual-frequency coexistence states or six single-frequency states. One. After that, the system will make further judgments. If the test speed in the current ranging and speed measurement results is less than zero, the object is moving in the direction of the terminal where the system is located. At this time, if the test distance in the current ranging and speed measurement results is greater than 30 meters and less than 500 meters, the system will cut in 2.4GHz/5GHz multi-input multi-output dual-frequency multi-transceiver module communication mode, the system at this time can exchange a large amount of data information, such as the interaction of pictures and video data. As shown in Figure 9, the MIMO dual-frequency multi-transceiver module communication mode also has sixteen dual-frequency coexistence states, and the system can only work in one of sixteen dual-frequency coexistence states or eight single-frequency states. The time for the system to work in the 2.4GHz/5GHz dual-frequency MIMO communication mode will not exceed 2 milliseconds, otherwise the system will automatically switch to the 5GHz ranging and speed measurement coarse mode or the 2.4GHz communication mode 504.

In the embodiment of the present invention, the adopted system antenna may include a dipole antenna, a patch antenna, an antenna array, etc., and a beamforming antenna may also be used to adjust the directivity of the antenna according to the system mode. Because the wireless local area network communication mode has the function of power control, the system also supports the function of power control. In addition, the system has the function of ranging and speed measurement, so that more perfect power control can be achieved by measuring the target distance and speed: If the target is at a short distance and moves towards the terminal where the system is located, the system will reduce the transmit power; if the target is at a short distance and move away from the terminal where the system is located, the system will increase the transmit power; if the target is at a long distance and move towards the terminal where the system is located When moving, the system will reduce the transmit power; if the target is far away and moving away from the terminal where the system is located, the system will increase the transmit power. Through this power control, the system can reduce power consumption.

FIG. 10 further illustrates the wireless local area network communication system for distance measurement and speed measurement provided by an embodiment of the present invention by taking three automatic or unmanned vehicles as an example. In Fig. 10, the car 99 simultaneously sends out wireless communication and distance measurement and speed measurement signals. If the distance 103 is equal to 100 meters, the car 99 can work in the 5GHz ranging and speed measurement fine mode and the 2.4GHz communication mode, or it can work in the 2.4GHz/5GHz multi-input multi-output dual-frequency multi-transceiver module communication mode, so as to test it and the car 100. distance, and the speed of the test vehicle 100, so as to realize comprehensive intelligent traffic control. In the 5GHz ranging and speed measurement fine mode and 2.4GHz communication mode, the car 99 and the car 100 are point-to-point wireless communication, and the car 99 can carry out 802.11g, 802.11b, 802.11n, 802.11 with the wireless access points 107, 105 or 106 along the road a, 802.11ac or 802.11p communication. In the 2.4GHz/5GHz dual-band MIMO communication mode, the car 99 and the car 100 are in point-to-point wireless communication, and the car 99 can perform 802.11g, 802.11b and 802.11n with the wireless access points 107, 105 or 106 along the road Communication. Conversely, the car 100 can also work in the 5GHz ranging and speed measuring fine mode and the 2.4GHz communication mode, perform wireless communication, and measure the distance and speed of the car 99 . If the distance 104 is equal to 600 meters, the car 99 works in the 2.4GHz ranging and speed measurement coarse mode and the 5GHz communication mode, the car 99 tests its distance from the car 101, and tests the speed of the car 101 to realize comprehensive intelligent traffic control. The car 99 and the car 101 are in point-to-point wireless communication, and the car 99 can communicate with the wireless access points 107, 105 or 106 along the road for 802.11a, 802.11ac and 802.11p communication. Similarly, the car 101 also works in the 2.4GHz ranging and speed measurement coarse mode and the 5GHz communication mode, performs wireless communication, and measures the distance and speed of the car 99. If the distance 104 is equal to 400 meters, the car 101 and the car 100 can work in 5GHz ranging. Speed measurement fine mode and 2.4GHz communication mode and 2.4GHz/5GHz multi-input multi-output dual-frequency multi-transceiver module communication mode, for wireless communication and ranging and speed measurement between each other. The wireless local area network communication system for distance measurement and speed measurement provided by the embodiment of the present invention can realize vehicle-to-vehicle (Vehicle-to-Vehicle, V2V) or vehicle-to-everything (Vehicle-to-Everything, V2X) communication and distance measurement and speed measurement.

The wireless local area network communication system for distance measurement and speed measurement provided by the embodiment of the present invention can realize automatic driving or independent communication between unmanned vehicles and unmanned aerial vehicles to avoid collision. The communication system has a small transformation and is easy to implement. The distance measurement and speed measurement functions of the same frequency duplex transmission and reception are truly realized in different transceiver modules of the wireless system, and the accuracy of distance measurement and speed measurement is guaranteed. Because the system can realize point-to-point communication between moving objects and mobile objects, as well as communication between moving objects and wireless network access points, it can work independently in various areas. Moving objects can measure the distance and speed of other objects through this system, and can also exchange information through this system, so that the communication peer knows that its information does not need to be based on mobile communication equipment, but only needs to be based on point-to-point or wireless access points. send out. This system can prevent collisions between moving objects and unnecessary deceleration or acceleration. Any object that can realize intelligent control can measure each other's speed, direction and distance through this system, and exchange information to judge the next action and Trend, all functions of this system can be realized in one-to-one, one-to-many and many-to-many communication scenarios.

The above-mentioned embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it is still possible to implement the foregoing implementations. The technical solutions described in the examples are modified, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the within the protection scope of the present invention.

Claims (10)

1. a wireless local area network communication system for distance measurement and speed measurement, the system supports multiple input and output, at least comprising a first transceiver module and a second transceiver module, it is characterized in that, for the transmitter configuration of the first transceiver module a coupler, and configure a switch for the receiver mixer of the second transceiver module; When the switch in the receiver of the second transceiving module works in the first state, the first transceiving module and the second transceiving module work in the communication mode, wherein the transceiving module working in the communication mode The communication modulated signal transmitted by the transmitter is demodulated under the processing of the receiver of the transceiver module to obtain demodulated data; When the switch in the receiver of the second transceiver module works in the second state, the first transceiver module and the second transceiver module work in the ranging and speed measurement mode; In the ranging and speed measurement mode, a part of the signal transmitted by the first transceiver module is transmitted through a transmitting antenna, and the rest is coupled to the second transceiver module through a coupler, and received with the second transceiver module The received reflected signal is mixed to realize the transmission and reception of ranging and speed measurement signals at the same time. 2 . The system of claim 1 , wherein the ranging and speed measuring signals comprise continuous wave signals or continuous wave frequency modulation signals. 3 . 3. The system according to claim 1 or 2, wherein the system operates on a single frequency, comprising: The first transceiver module and the second transceiver module work at 2.4GHz simultaneously; or, The first transceiver module and the second transceiver module work at 5GHz at the same time. 4. The system of claim 3, wherein the system switches between the communication mode and the ranging and speed measurement mode according to the distance measurement and speed measurement results. 5. The system according to claim 4, wherein, according to the result of ranging and speed measurement, the system switching between the communication mode and the ranging and speed measurement mode comprises: making the first transceiver module and the second transceiver module work in the ranging and speed measurement mode; When a preset switching condition is met, the first transceiver module and the second transceiver module are switched to the communication mode, and relevant information about the current ranging and speed measurement result is sent; After completing the sending of the relevant information, the first transceiver module and the second transceiver module are switched back to the ranging and speed measuring mode. 6. The system according to claim 5, wherein when a preset switching condition is satisfied, switching the first transceiver module and the second transceiver module to the communication mode comprises: If the test distance in the current distance measurement and speed measurement result is within a preset first distance value interval, switch the first transceiver module and the second transceiver module to the communication mode; or If the test speed in the current ranging and speed measurement result is less than or equal to 0, and the test distance in the current ranging and speed measurement result is within the preset second distance value interval, the first transceiver module and the The second transceiver module switches to the communication mode. 7. The system according to claim 1 or 2, wherein the system operates in dual frequency, further comprising a third transceiver module and a fourth transceiver module, and a coupler is configured for the transmitter of the third transceiver module, and configure a switch for the receiver mixer of the fourth transceiver module; The first transceiver module and the second transceiver module work at 2.4GHz simultaneously, and the third transceiver module and the fourth transceiver module work at 5GHz at the same time. 8. The system of claim 7, wherein The switch in the receiver of the second transceiving module works in the first state, and the switch in the receiver of the fourth transceiving module works in the second state, so that the first transceiving module and the The second transceiver module works in a communication mode, and the third transceiver module and the fourth transceiver module work in a ranging and speed measurement mode; or, The switch in the receiver of the second transceiving module works in the second state, and the switch in the receiver of the fourth transceiving module works in the first state, so that the first transceiving module and the The second transceiver module works in a ranging and speed measurement mode, and the third transceiver module and the fourth transceiver module work in a communication mode; or, The switches in the receivers of the second transceiving module and the fourth transceiving module work in the first state, so that the first transceiving module, the second transceiving module, and the third transceiving module Both the module and the fourth transceiver module work in a communication mode. 9. The system of claim 8, wherein Make the switch in the receiver of the second transceiver module work in the second state, and the switch in the receiver of the fourth transceiver module work in the first state, to obtain a first ranging and speed measurement result; If the test distance in the first distance measurement and speed measurement result is smaller than the preset distance threshold, the switch in the receiver of the second transceiver module is set to work in the first state, and the receiver of the fourth transceiver module is set to work in the first state. The switches in are operated in the second state. 10. The system of claim 8, wherein If the first transceiver module and the second transceiver module work in the communication mode, and the third transceiver module and the fourth transceiver module work in the ranging and speed measurement mode, the first transceiver module and the The second transceiver module sends the current ranging and speed measurement results in real time; If the first transceiving module and the second transceiving module work in the ranging and speed measurement mode, and the third transceiving module and the fourth transceiving module work in the communication mode, the third transceiving module and the The fourth transceiver module sends the current ranging and speed measurement results in real time.