Wireless transmission system and method with precise and controllable space transmission position

Abstract

The invention discloses a wireless transmission system and method with a precise and controllable space transmission position, and the system comprises a frequency control array communication machine and a single-antenna communication machine which is used for initiating a communication request and a data transmission request, and the frequency control array communication machine comprises a baseband receiving part, a baseband transmitting part, and a radio frequency receiving and transmitting channel. The radio frequency transceiving channel receives a communication request or a data transmission request and sends the request to the baseband receiving part; the baseband receiving part estimates the distance and angle of the single-antenna communication machine according to the request signal, obtains the position information of the single-antenna communication machine, and obtains information about whether the single-antenna communication machine is successfully received or not; and the baseband transmitting part forms a downlink transmission frame according to the communication request or the information about whether the communication request is successfully received or not, the baseband transmitting part controls the carrier frequency and the phase of the downlink transmission frame according to the position information, and the downlink transmission frame is transmitted to the single-antenna communication machine through the radio frequency transceiving channel. Therefore, fixed-point and controllable hidden secure transmission of communication information space is realized, and the anti-interception and anti-eavesdropping performance of high-dynamic communication is improved.

Description

Technical Field

[0001] The present invention relates to a wireless transmission system and method with accurately controllable spatial transmission position, belonging to the technical field of radio transmission. Background Art

[0002] With the continuous development of modern electronic warfare communication countermeasure technology, more and more advanced communication reconnaissance, interception and eavesdropping technologies and equipment have emerged, and wireless communication system signals are at risk of being intercepted and eavesdropped. Traditional anti-interception and anti-eavesdropping communication technologies mainly include multi-antenna directional narrow beam communication, low-power transmission technology and anti-interception waveform design technology. Multi-antenna directional narrow beam communication and low-power transmission technology mainly achieve stealth communication by controlling the signal radiation distance and range. Anti-interception waveform design mainly adopts spread frequency hopping communication technology, transform domain communication technology and non-stationary signal processing technology to resist the typical characteristics of the opponent's communication reconnaissance equipment detecting our communication signals, so that the communication system has a certain anti-interception and anti-eavesdropping ability. However, with the continuous development of the opponent's communication countermeasure technology, the above-mentioned anti-interception and anti-eavesdropping communication technology is increasingly difficult to cope with the opponent's increasingly advanced high-sensitivity and intelligent communication reconnaissance equipment in the future. Although the extremely narrow beam directional communication through a fully digital large-scale antenna array can further improve the system's anti-interception and anti-eavesdropping performance, it will lead to a sharp increase in product costs.

[0003] On the other hand, physical layer security technology means that use the physical characteristics of the wireless communication system itself to design corresponding security mechanisms have gradually become a new security paradigm in wireless communication systems. Directional modulation technology is one of the technologies in the field of physical layer security research. Directional modulation technology is based on traditional phased arrays. By optimizing the array beam weighting vector, it can achieve information security transmission in the desired direction, and the signal in the undesired direction is severely distorted. However, directional modulation technology cannot achieve secure transmission in the distance dimension and cannot achieve the purpose of precise spatial fixed-point secure transmission. Frequency-controlled array is a new system array technology proposed in recent years. By adding a small frequency offset to different channels, its beam pattern becomes a function that changes with distance, angle and time in the far field. According to the beam pattern that is both distance and azimuth dependent, it is expected to achieve anti-interception and anti-eavesdropping secure communication with spatial concealment of signal position. Although domestic and foreign scholars have proposed some spatial fixed-point secure communication algorithms based on the frequency-controlled array theory, they have not considered the characteristics of actual application scenarios such as high dynamic communication, and have not designed a wireless transmission system with precise and controllable spatial transmission position from a feasible perspective. Summary of the invention

[0004] The technical problem solved by the present application is: to overcome the deficiencies of the prior art, to provide a new type of wireless transmission system and method with precise and controllable spatial transmission position, to achieve fixed-point, controllable, covert and secure transmission of communication information in space, and to enhance the anti-interception and anti-eavesdropping performance of high-dynamic communications.

[0005] The technical solutions provided by this application are as follows:

[0006] A wireless transmission system with a precisely controllable spatial transmission position, comprising a frequency-controlled array communication machine and a single-antenna communication machine, wherein the frequency-controlled array communication machine comprises a baseband receiving part, a baseband transmitting part and a radio frequency transceiver channel;

[0007] A single-antenna communicator is used to initiate a communication request and send a data transmission request, and send the communication request and the data transmission request to the radio frequency transceiver channel, and the data transmission request carries a successful reception or failure mark;

[0008] The radio frequency transceiver channel receives the above communication request or data transmission request and sends the communication request or data transmission request to the baseband receiving part;

[0009] The baseband receiving part estimates the distance and angle of the single-antenna communicator according to the communication request or the data transmission request, obtains the position information of the single-antenna communicator, and sends the position information of the single-antenna communicator to the baseband transmitting part, obtains the successful reception information according to the data transmission request, and sends the communication request or the successful reception information to the baseband transmitting part;

[0010] The baseband transmitting part forms a downlink space fixed point covert transmission frame according to the communication request or the successful reception information. The baseband transmitting part controls the carrier frequency and phase of the downlink space fixed point covert transmission frame during the transmission process according to the position information of the above-mentioned single antenna communicator. The downlink space fixed point covert transmission frame is sent to the single antenna communicator through the RF transceiver channel.

[0011] The baseband receiving part includes a multi-antenna signal processing module, a synchronization and frequency offset compensation module, a baseband demodulation module, a channel decoding module and a positioning sensing module. The RF transceiver channel sends the received communication request or data transmission request to the multi-antenna signal processing module and the positioning sensing module. The positioning sensing module estimates the angle and distance of the single-antenna communicator according to the data transmission request signal to obtain the position information of the single-antenna communicator; the positioning sensing module sends the estimated position information of the single-antenna communicator to the multi-antenna signal processing module for beamforming on the one hand, and sends it to the baseband transmitting part on the other hand to generate the carrier frequency values ​​and phase shift values ​​of each channel required for the downlink spatial fixed-point covert transmission; the multi-antenna signal processing module uses the weighted values ​​of each channel obtained by beamforming to weightedly combine the signals received by the multi-antennas, and uses the synchronization and carrier frequency offset compensation module to calculate the carrier frequency offset, and compensates to eliminate the carrier frequency offset caused by the Doppler effect of the high-speed movement of the communication node; then the baseband demodulation module and the channel decoding module are used to demodulate and decode to obtain the uplink feedback data information, and the uplink feedback data information includes whether the previous frame of data is successfully received or not.

[0012] The baseband transmission part includes a channel coding module, a baseband modulation module, a shaping and filtering module and a framing module. The transmission bit stream is channel coded by the channel coding module to obtain the coded transmission data, and then the coded transmission data is digitally modulated by the baseband modulation module to obtain the transmission symbol. The transmission symbol is mapped to the transmission bit stream into a baseband transmission signal by the shaping and filtering module. The baseband transmission signal is added with a signal capture and synchronization sequence on the basis of the baseband transmission signal data by the framing module to form a downlink spatial fixed-point covert transmission frame.

[0013] The baseband transmitting part also includes a distance-angle dimension joint precoding module, which generates the carrier frequency value and phase shift value of each channel required for the downlink spatial fixed-point covert transmission according to the position information of the single-antenna communicator estimated by the baseband receiving part, and controls the carrier frequency and phase of the downlink spatial fixed-point covert transmission frame during the transmission process through the RF transceiver channel according to the carrier frequency value and phase shift value of each channel.

[0014] The RF transceiver channel includes a transmitting channel, a receiving channel and a switch matrix. The switch matrix includes multiple switches, each switch is connected to an antenna, and each switch is connected to a receiving channel and a transmitting channel. The other end of the receiving channel is connected to a multi-antenna signal processing module and a positioning perception module, and the other end of the transmitting channel is connected to a framing module. The transceiver mode of the frequency-controlled array communicator is switched by switching the switch.

[0015] The transmission channel includes a mixer, a phase shifter and a PA. The downlink spatial fixed-point covert transmission frame formed by the baseband transmission part passes through a DAC device to form an analog baseband signal, which is then transmitted to the transmission channel corresponding to each antenna. Different carrier frequency values ​​and phase values ​​are loaded in different transmission channels through mixers and phase shifters and sent out through the PA.

[0016] The location information of the single-antenna communication device includes distance information and angle information.

[0017] The data transmission request forms an uplink feedback signal data frame. The downlink spatial fixed-point covert transmission frame has the same structure as the uplink feedback signal data frame, both of which include a signal capture sequence, a synchronization sequence, a transmission data part and a protection interval. The signal capture sequence is mainly used for signal capture, and the synchronization sequence is used to estimate the carrier frequency deviation caused by the Doppler effect and to compensate for the carrier frequency deviation. The transmission data part in the downlink spatial fixed-point covert transmission frame is the covert transmission data, and the transmission data part in the uplink feedback signal transmission frame is the single-antenna communication machine feedback data. The protection interval is mainly used for transmission delay and processing delay protection.

[0018] A transmission method of a wireless transmission system with a precisely controllable spatial transmission position based on any of the above-mentioned methods comprises:

[0019] After the frequency-controlled array communication machine and the single-antenna communication machine are turned on, the frequency-controlled array communication machine is in receiving mode, waiting to receive a communication request initiated by the single-antenna communication machine;

[0020] After the single-antenna communication machine sends a communication request, it enters the receiving mode. After the frequency-controlled array communication machine receives the communication request initiated by the single-antenna communication machine, it estimates the angle and distance information of the single-antenna communication machine according to the communication request received from the single-antenna communication machine, and generates a distance-angle joint precoding vector according to the estimated distance and angle information. Then, the frequency-controlled array communication machine enters the sending mode, loads the frequency deviation value and phase shift value of the frequency-controlled array, and transmits the downlink spatial fixed-point concealed transmission frame. After the transmission is completed, it switches to the receiving mode.

[0021] After the single-antenna communication machine captures the downlink spatial fixed-point covert transmission frame sent by the frequency-controlled array communication machine, it performs frequency offset compensation, demodulation and decoding, and feeds back the data transmission request; if the single-antenna communication machine successfully receives it, the frequency-controlled array communication machine transmits the next frame of data, otherwise it repeats the previous frame of data;

[0022] The above process works in a cycle to perform continuous data transmission.

[0023] The beneficial effects of the present invention compared with the prior art are:

[0024] (1) The wireless transmission system with precise and controllable spatial transmission position proposed in the present invention adopts a frequency control array and directional modulation technology, and takes into account the Doppler effect caused by node movement. Based on the feasible perspective, the overall system architecture of spatial fixed-point secure transmission, the uplink and downlink transmission frame structure and the overall system workflow are designed, which realizes the spatial fixed-point covert transmission of communication signals under high-dynamic communication conditions. It can be applied to high-dynamic communication application scenarios such as drone clusters in complex electromagnetic confrontation environments, and improves the network's anti-interception and anti-eavesdropping capabilities.

[0025] (2) Based on the integrated design concept of communication and perception, the present invention proposes an independent, online closed-loop control mechanism for spatial transmission position. By autonomously perceiving the angle and distance information of communication nodes in real time, the present invention realizes precise control of the spatial transmission position without external auxiliary position information. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the structure of a wireless transmission system with precise and controllable spatial transmission position designed for the present invention;

[0027] Figure 2 The downlink spatial fixed-point concealed transmission data frame structure and uplink feedback signal data frame structure designed for the present invention;

[0028] Figure 3 The figure is a schematic diagram of the overall working process of the system. DETAILED DESCRIPTION

[0029] In order to make the objectives, technical solutions and advantages of the present invention more clear, the embodiments disclosed in the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] The present invention is aimed at high-dynamic communication application scenarios. Considering the high dynamic characteristics of nodes in this scenario, a wireless transmission system with precise and controllable spatial transmission position is proposed from a feasible perspective. The system jointly adopts frequency control array and directional modulation technology to generate point beams through the frequency control array, and utilizes the characteristics of scrambling the communication signal constellation diagram in non-desired directions by directional modulation technology to achieve precise transmission of communication signals to the desired position. At the same time, in order to achieve precise control of the spatial transmission position during the high-speed movement of communication nodes, the system adopts time division duplex (TDD) mode, combined with the integrated design idea of ​​communication and perception, and perceives the position of the moving node in real time by receiving the feedback signal of the moving node, which is used for accurate control of the spatial transmission position. It realizes the fixed-point concealed and secure transmission of communication information in space under high-dynamic conditions, and improves the anti-interception and anti-eavesdropping performance of high-dynamic communication networks in complex electromagnetic confrontation scenarios.

[0031] The embodiment of the present application discloses a wireless transmission system with precise and controllable spatial transmission position. The specific technical solution is as follows:

[0032] like Figure 1 As shown, the transmission system consists of a frequency-controlled array communicator and a single-antenna communicator. The frequency-controlled array communicator is mainly used to covertly send information to the desired location. The main function of the single-antenna communicator is to receive the transmitted wireless data at the legal desired location.

[0033] The frequency-controlled array communication device is mainly composed of a baseband receiving part, a baseband transmitting part and a radio frequency transceiver channel, and deploys a frequency-controlled array of N elements.

[0034] The baseband transmission part of the frequency-controlled array communication machine mainly includes a channel coding module, a baseband modulation module, a shaping filter module and a framing module. The transmission bit stream is channel-coded by the channel coding module (the channel coding method can be selected as Turbo coding, LDPC coding, etc.) to obtain the coded transmission data, and then the coded transmission data is passed through the baseband modulation module, which can select digital modulation methods such as QPSK modulation and QAM modulation to obtain the transmission symbol. The transmission symbol is mapped to the baseband transmission signal by the shaping filter module. The baseband transmission signal is added with the signal capture and synchronization sequence on the basis of the baseband transmission signal data through the framing module to form a downlink space fixed-point covert transmission frame. The known signal capture and synchronization sequence of the transceiver (the transceiver refers to the frequency-controlled array communication machine and the single antenna communication machine) is used by the receiver to capture the signal and estimate and compensate for the frequency deviation to eliminate the carrier frequency deviation caused by the Doppler effect of the high-speed movement of the communication node. In the baseband transmission part, the distance-angle dimension joint precoding module is the core module, which mainly uses the estimated position information of the single-antenna communicator (including distance and angle information) to generate the carrier frequency and phase of each channel in the front-end transmission channel using an optimization algorithm, and controls the carrier frequency and phase of the mixer and phase shifter. The mixer and phase shifter are used to control the carrier frequency and phase of the downlink spatial fixed-point covert transmission frame during the transmission process.

[0035] The baseband receiving part of the frequency-controlled array communication machine is mainly used to receive the successful reception signal of the uplink feedback of the single-antenna communication machine, and estimate the distance and angle of the single-antenna communication machine based on the signal to obtain the location information of the node. The baseband receiving part mainly includes a multi-antenna signal processing module, a synchronization and frequency offset compensation module, a baseband demodulation module, a channel decoding module and a positioning perception module. After the frequency-controlled array communication machine receives the uplink feedback signal of the single-antenna communication machine through the RF transceiver channel (multiple antennas) in the receiving mode, the received uplink feedback signal is divided into two paths and sent to the multi-antenna signal processing module and the positioning perception module respectively. According to the received uplink feedback signal, the positioning perception module mainly uses the DOA estimation algorithm to estimate the angle of the single-antenna communication machine, and uses the RSSI ranging algorithm to estimate the distance of the single-antenna communication machine to obtain angle information and distance information. The angle information and distance information estimated by the positioning perception module are sent to the multi-antenna signal processing module for beamforming on the one hand, and to the distance-angle dimension joint precoding module in the baseband transmission part on the other hand to generate the carrier frequency values ​​and phase shift values ​​of each channel required for the downlink spatial fixed-point covert transmission. The multi-antenna signal processing module uses the weighted values ​​of each channel obtained by beamforming to weightedly combine the signals received by multiple antennas, and then uses the synchronization and carrier frequency offset compensation module to calculate the carrier frequency offset and compensate to eliminate the carrier frequency offset caused by the Doppler effect of the high-speed movement of the communication node. Then, the baseband demodulation module and the channel decoding module are used to demodulate and decode to obtain the data information fed back by the uplink of the single-antenna communication machine.

[0036] The front-end RF transceiver channel of the frequency-controlled array communicator mainly includes a transmitting channel, a receiving channel and a switch matrix. The switch matrix includes multiple switches, each switch is connected to an antenna, and each switch is connected to a receiving channel and a transmitting channel. The other end of the receiving channel is connected to the multi-antenna signal processing module and the positioning perception module, and the other end of the transmitting channel is connected to the framing module. The transceiver mode of the frequency-controlled array communicator is switched by switching the switch. In the designed system, each antenna is connected to a separate RF transceiver channel to form a fully digital array. Each transmitting channel mainly includes a mixer, a phase shifter, a PA, etc. The digital baseband signal formed by the baseband transmitting part is converted into an analog baseband signal through a DAC device, and then transmitted to the transmitting channel corresponding to each antenna. Different transmitting channels are loaded with different carrier frequency values ​​and phase values, and sent out through the PA to form an electromagnetic wave propagation signal with a spatial fixed-point concealed transmission effect. Each receiving channel mainly includes LNA, filter, downconverter, ADC devices, etc. The frequency-controlled array communication machine uses the uplink feedback signal received by multiple antennas, downconverts, filters, and samples through their respective receiving channels to form N digital sampling signals that are sent to the baseband receiving part for processing. The switch matrix is ​​mainly used for the frequency-controlled array communication machine to switch the transmit and receive modes.

[0037] The spatial fixed-point transmission receiving node mainly adopts a single-antenna communicator to reduce system complexity. The single-antenna communicator is mainly composed of a baseband receiving part, a baseband transmitting part and a radio frequency transceiver channel, which is basically the same as the traditional communication transceiver structure.

[0038] The baseband transmitting part of a single-antenna communication machine mainly includes a channel coding module, a baseband modulation module, a shaping filter module, and a framing module, which are used to generate baseband data for uplink feedback signals. The processing flow is basically the same as that of the baseband transmitting part of a frequency-controlled array communication machine. After coding and modulation, signal capture and synchronization sequences also need to be added during the framing process. The difference is that the data frame length of the uplink feedback signal is shorter. The baseband receiving part of a single-antenna communication machine mainly includes a synchronization and frequency offset compensation module, a baseband demodulation module, and a channel decoding module, which are used to receive and process wireless data sent by a downlink frequency-controlled array communication machine. The front-end RF channel is mainly used to convert the transmitted / received digital baseband signal into an analog RF signal.

[0039] In order to achieve independent and online precise control of the spatial transmission position under high dynamic conditions, the system adopts the time division duplex (TDD) method, and the frequency-controlled array communication machine and the single antenna communication machine switch the sending and receiving modes in time to realize information interaction. Figure 2 As shown in the figure, the structure of the downlink spatial fixed-point concealed transmission frame is basically similar to that of the uplink feedback signal data frame, and is mainly composed of a signal capture sequence, a synchronization sequence, a transmission data part, and a protection interval. The signal capture sequence is mainly used for signal capture, the synchronization sequence is used to estimate the carrier frequency offset caused by the Doppler effect and to compensate for the carrier frequency offset, the transmission data part in the downlink spatial fixed-point concealed transmission frame is concealed transmission data, and the transmission data part in the uplink feedback signal transmission frame is single-antenna communication machine feedback data (including communication request, reception success, reception failure, etc. identification data), and the protection interval is mainly used for transmission delay and processing delay protection.

[0040] like Figure 3As shown in the figure, based on the designed transmission frame structure, the overall workflow of the system is as follows: after the frequency-controlled array communication machine and the single-antenna communication machine are turned on, the frequency-controlled array communication machine is in the receiving mode, waiting to receive the communication request initiated by the single-antenna communication machine. After the single-antenna communication machine sends the communication request, it enters the receiving mode. After the frequency-controlled array communication machine receives the communication request initiated by the single-antenna communication machine, it starts the positioning perception algorithm, estimates the angle and distance information of the single-antenna communication machine, and generates the distance-angle joint precoding vector according to the estimated distance and angle information. Then the frequency-controlled array communication machine enters the sending mode, loads the frequency-controlled array frequency deviation value and phase shift value to transmit 1 frame of downlink spatial fixed-point concealed transmission frame, and switches to the receiving mode after the transmission is completed. After the single-antenna communication machine captures the signal, it performs frequency deviation compensation, demodulation, and decoding. Feedback the successful reception mark and data transmission request. If the single-antenna communication machine successfully receives, the frequency-controlled array communication machine transmits the next frame of data, otherwise it repeats the transmission of the previous frame of data. The above process works in a loop for continuous data transmission.

[0041] The contents not described in detail in this application specification belong to the common knowledge of those skilled in the art.

[0042] The present application is described in detail above in conjunction with specific implementation methods and exemplary examples, but these descriptions cannot be understood as limiting the present application. Those skilled in the art understand that, without departing from the spirit and scope of the present application, a variety of equivalent replacements, modifications or improvements can be made to the technical solution of the present application and its implementation methods, all of which fall within the scope of the present application. The scope of protection of the present application shall be subject to the attached claims.

Claims

1. A wireless transmission system with precise and controllable spatial transmission position, characterized in that: It includes a frequency-controlled array communication machine and a single-antenna communication machine, wherein the frequency-controlled array communication machine includes a baseband receiving part, a baseband transmitting part and a radio frequency transceiver channel; A single-antenna communicator is used to initiate a communication request and send a data transmission request, and send the communication request and the data transmission request to the radio frequency transceiver channel, and the data transmission request carries a successful reception or failure mark; The radio frequency transceiver channel receives the above communication request or data transmission request and sends the communication request or data transmission request to the baseband receiving part; The baseband receiving part estimates the distance and angle of the single-antenna communicator according to the communication request or the data transmission request, obtains the position information of the single-antenna communicator, and sends the position information of the single-antenna communicator to the baseband transmitting part, obtains the successful reception information according to the data transmission request, and sends the communication request or the successful reception information to the baseband transmitting part; The baseband transmitting part forms a downlink space fixed point covert transmission frame according to the communication request or the successful reception information. The baseband transmitting part controls the carrier frequency and phase of the downlink space fixed point covert transmission frame during the transmission process according to the position information of the above-mentioned single antenna communicator. The downlink space fixed point covert transmission frame is sent to the single antenna communicator through the RF transceiver channel.

2. A wireless transmission system with precise and controllable spatial transmission position according to claim 1, characterized in that: The baseband receiving part includes a multi-antenna signal processing module, a synchronization and frequency offset compensation module, a baseband demodulation module, a channel decoding module and a positioning perception module; The multi-antenna signal processing module and the positioning sensing module receive communication requests or data transmission requests sent by the radio frequency transceiver channel; A positioning sensing module estimates the angle and distance of the single-antenna communication machine according to the data transmission request, obtains the position information of the single-antenna communication machine, and sends the estimated position information of the single-antenna communication machine to the multi-antenna signal processing module on the one hand and to the baseband transmission part on the other hand; A multi-antenna signal processing module performs beamforming according to the position information of the single-antenna communication machine, and uses the weighted values ​​of each channel obtained by beamforming to weightedly combine the signals received by the multi-antennas, and uses the synchronization and carrier frequency offset compensation module to calculate the carrier frequency offset, and compensates to eliminate the carrier frequency offset caused by the Doppler effect of the high-speed movement of the communication node; Then, the baseband demodulation module and the channel decoding module are used to demodulate and decode the data information fed back by the uplink, and the data information fed back by the uplink includes information on whether the previous frame of data is successfully received or not.

3. A wireless transmission system with precise and controllable spatial transmission position according to claim 1 or 2, characterized in that: The baseband transmission part includes a channel coding module, a baseband modulation module, a shaping filter module and a framing module; The channel coding module performs channel coding on the transmission bit stream to obtain the coded transmission data, and sends the coded transmission data to the baseband modulation module; A baseband modulation module performs digital modulation on the encoded transmission data to obtain transmission symbols, and sends the transmission symbols to the shaping filter module; A shaping and filtering module maps the transmission bit stream of the transmission symbol into a baseband transmission signal, and transmits the baseband transmission signal to a framing module; The framing module adds a signal capture and synchronization sequence to the baseband transmission signal based on the baseband transmission signal data to form a downlink spatial fixed-point concealed transmission frame.

4. A wireless transmission system with precise and controllable spatial transmission position according to claim 3, characterized in that: The baseband transmitting part also includes a distance-angle dimension joint precoding module, which generates the carrier frequency value and phase shift value of each channel required for the downlink spatial fixed-point covert transmission according to the position information of the single-antenna communicator estimated by the baseband receiving part, and controls the carrier frequency and phase of the downlink spatial fixed-point covert transmission frame during the transmission process through the RF transceiver channel according to the carrier frequency value and phase shift value of each channel.

5. The wireless transmission system with precise and controllable spatial transmission position according to claim 3, characterized in that: The RF transceiver channel includes a transmitting channel, a receiving channel and a switch matrix. The switch matrix includes multiple switches, each switch is connected to an antenna, and each switch is connected to a receiving channel and a transmitting channel. The other end of the receiving channel is connected to a multi-antenna signal processing module and a positioning perception module, and the other end of the transmitting channel is connected to a framing module. The transceiver mode of the frequency-controlled array communicator is switched by switching the switch.

6. A wireless transmission system with precise and controllable spatial transmission position according to claim 5, characterized in that: The transmission channel includes a mixer, a phase shifter and a PA. The downlink spatial fixed-point covert transmission frame formed by the baseband transmission part passes through a DAC device to form an analog baseband signal, which is then transmitted to the transmission channel corresponding to each antenna. Different carrier frequency values ​​and phase values ​​are loaded in different transmission channels through mixers and phase shifters and sent out through the PA.

7. The wireless transmission system with precise and controllable spatial transmission position according to claim 1, characterized in that: The location information of the single-antenna communication device includes distance information and angle information.

8. The wireless transmission system with precise and controllable spatial transmission position according to claim 1, characterized in that: The baseband receiving part obtains the data information of the uplink feedback according to the data transmission request. The data information of the uplink feedback is the uplink feedback signal data frame. The downlink spatial fixed-point covert transmission frame has the same structure as the uplink feedback signal data frame, and both include a signal capture sequence, a synchronization sequence, a transmission data part and a protection interval. The signal capture sequence is mainly used for signal capture, and the synchronization sequence is used to estimate the carrier frequency deviation caused by the Doppler effect and to compensate for the carrier frequency deviation. The transmission data part in the downlink spatial fixed-point covert transmission frame is the covert transmission data, and the transmission data part in the uplink feedback signal transmission frame is the single-antenna communication machine feedback data. The protection interval is mainly used for transmission delay and processing delay protection.

9. A transmission method for a wireless transmission system with a precisely controllable spatial transmission position according to any one of claims 1 to 8, characterized in that: include: After the frequency-controlled array communication machine and the single-antenna communication machine are turned on, the frequency-controlled array communication machine is in receiving mode, waiting to receive a communication request initiated by the single-antenna communication machine; After sending a communication request, the single-antenna communication machine enters the receiving mode. After receiving the communication request initiated by the single-antenna communication machine, the frequency-controlled array communication machine estimates the angle and distance information of the single-antenna communication machine according to the communication request received from the single-antenna communication machine, and generates a distance-angle joint precoding vector according to the estimated distance and angle information. Then, the frequency-controlled array communication machine enters the sending mode, loads the frequency deviation value and phase shift value of the frequency-controlled array, and transmits the downlink spatial fixed-point concealed transmission frame. After the transmission is completed, it switches to the receiving mode. After the single-antenna communication machine captures the downlink spatial fixed-point covert transmission frame sent by the frequency-controlled array communication machine, it performs frequency offset compensation, demodulation and decoding, and feeds back the data transmission request; if the single-antenna communication machine successfully receives it, the frequency-controlled array communication machine transmits the next frame of data, otherwise it repeats the previous frame of data; The above process works in a cycle to perform continuous data transmission.

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