Anti-interference wireless laser flight control communication system

Abstract

At present, an anti-unmanned aerial vehicle system uses interference blocking type unmanned aerial vehicle interference equipment most widely, that is, communication or hardware of an unmanned aerial vehicle is interfered by means of electromagnetic waves, sound waves and the like, and the unmanned aerial vehicle is forced to return automatically or land automatically. The frequency of the laser is more than 100,000 times of the frequency of microwave (ultrahigh frequency electromagnetic wave), and the wavelength of the laser is very short, so that the volatility of the laser is far poorer than that of radio waves. And on the contrary, the laser has peculiar particle property, so that the laser becomes an attractive'later show 'in military communication. The invention discloses an anti-interference wireless laser flight control communication system which comprises a ground wireless terminal and an airborne wireless terminal. The ground wireless terminal is mounted on the ground; the airborne wireless terminal is mounted on the unmanned aerial vehicle; the ground wireless terminal and the airborne wireless terminal have the same structure, and each of the ground wireless terminal and the airborne wireless terminal consists of an optical transceiver, an optical antenna and a tracking detector. The laser is used as an information carrier and is not easily interfered by the outside; and laser is used for positioning, so that external interference is avoided.

Description

Technical Field

[0001] The invention relates to the field of communication technology, and in particular to the technical field of an anti-interference wireless laser flight control communication system. Background Art

[0002] UAV communication links require the use of radio resources. Currently, the spectrum used by drones in the world is mainly concentrated in the UHF, L and C bands, with scattered distribution in other frequency bands.

[0003] At present, the most widely used anti-drone system is the jamming and blocking type of drone jamming equipment, which uses electromagnetic waves, sound waves and other methods to interfere with the drone's communication or hardware, forcing the drone to automatically return or land. There are currently several main types of jamming.

[0004] 1. Electromagnetic interference Electromagnetic interference can effectively block the communication between the drone and the control station, cut off the drone's remote control signal as well as the data and image transmission signals, and cause the drone to enter a self-protection state after signal loss, thereby achieving the purpose of forced landing or driving away the drone.

[0005] 2. Navigation signal interference Civilian drones generally use satellite navigation and positioning systems to locate themselves. Interference with the navigation signal can be achieved by jamming the drone. After losing the navigation signal, the drone cannot be accurately positioned, which affects the flight control system of the drone and restricts the flight of the drone. Since the navigation signal is weak, this interference method is easy to implement.

[0006] Drone jammers are openly sold on the market. They can interfere with the data link and positioning system of radio drones, cut off the communication and navigation between the drone and the remote control, and force the drone to land automatically or drive it away. This gives criminals a means of counter-drone reconnaissance. This is very unfavorable for aerial reconnaissance operations using radio drones, so new methods need to be found to overcome this problem.

[0007] Laser is a light wave that also has the properties of electromagnetic waves. However, laser is significantly different from ordinary radio waves. The frequency of laser is 300THz, which is more than 100,000 times the frequency of microwave (ultra-high frequency electromagnetic wave). From the relationship between wavelength, wave speed and frequency, it can be seen that the wavelength of laser is very short, so its volatility is far worse than that of radio waves. On the contrary, laser has a peculiar particle property, which makes it a striking "rising star" in military communications. Summary of the invention

[0008] The problem to be solved by the present invention is that the existing radio UAV is interfered by the counter-UAV system, and an anti-interference wireless laser flight control communication system is provided.

[0009] To solve the above problems, the present invention is achieved through the following technical solutions: An anti-interference wireless laser flight control communication system includes a ground wireless terminal and an airborne wireless terminal; the ground wireless terminal is installed on the ground; the airborne wireless terminal is installed on a drone; the ground wireless terminal and the airborne wireless terminal have the same structure, and are both composed of an optical terminal, an optical antenna, and a tracking detector; the optical terminal includes a coding module, an optical wavelength division multiplexing module, a laser driving module, a laser, a light detector, a signal processing module, an optical wavelength decomposition multiplexing module, a decoding module, and a service interface module; the input end of the coding module is connected to the service interface module, the output end of the coding module is connected to the input end of the laser driving module via the optical wavelength division multiplexing module, and the output end of the laser driving module is connected to the input end of the laser; the output end of the light detector is connected to the input end of the optical wavelength decomposition multiplexing module via the signal processing module, the output end of the optical wavelength decomposition multiplexing module is connected to the input end of the decoding module, and the output end of the decoding module is connected to the service interface module; the optical antenna includes a receiving lens and a transmitting lens; the transmitting lens is connected to the output end of the laser through an optical fiber; the receiving lens is connected to the input end of the light detector through an optical fiber. The tracking detector includes a CCD camera and a four-quadrant detector.

[0010] In the above scheme, the optical antenna further includes a pitch adjustment knob, a pitch adjustment circuit, a pitch adjustment motor, an azimuth adjustment knob, an azimuth adjustment circuit, an azimuth adjustment motor and a universal adjustment base; the receiving lens and the transmitting lens are installed on the universal adjustment base; the pitch adjustment knob is connected to the input end of the pitch adjustment circuit, and the output end of the pitch adjustment circuit is connected to the universal adjustment base via the pitch adjustment motor; the azimuth adjustment knob is connected to the input end of the azimuth adjustment circuit, and the output end of the azimuth adjustment circuit is connected to the universal adjustment base via the azimuth adjustment motor.

[0011] Compared with the prior art, the present invention has the following characteristics: it uses laser control and communication and is not easily affected by external interference. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A schematic diagram of an anti-interference wireless laser flight control communication system.

[0013] Figure 2 The figure is a schematic diagram of the front panel of an anti-interference wireless laser flight control communication system terminal.

[0014] Figure 3 The figure is a schematic diagram of the principle of an optical transceiver of an anti-interference wireless laser flight control communication system.

[0015] Figure 4 The figure is a schematic diagram of the coarse tracking principle of a tracking detector for an anti-interference wireless laser flight control communication system.

[0016] Figure 5 The figure is a schematic diagram of the precise tracking principle of a tracking detector for an anti-interference wireless laser flight control communication system.

[0017] Figure 6 The figure is a schematic diagram of the principle of an optical antenna for an anti-interference wireless laser flight control communication system.

[0018] Numbers in the figure: 1. Ground wireless terminal; 2. Airborne wireless terminal; 3. Communication transmission window; 4. Communication receiving window; 5. Tracking and detection window; 6. The ground wireless terminal is the command transmission window, and the airborne wireless terminal is the command receiving window. Specific implementation methods

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific examples and with reference to the accompanying drawings.

[0020] An anti-interference wireless laser flight control communication system, such as Figure 1 As shown, it includes a ground wireless terminal and an airborne wireless terminal; the ground wireless terminal is supported by a tripod and placed on the ground; the airborne wireless terminal is suspended on the drone by a drone pod; the ground wireless terminal and the airborne wireless terminal have the same structure, and are both composed of an optical terminal, an optical antenna, and a tracking detector; the optical terminal includes a coding module, an optical wavelength division multiplexing module, a laser driving module, a laser, a light detector, a signal processing module, an optical wavelength decomposition multiplexing module, a decoding module, and a service interface module; the input end of the coding module is connected to the service interface module, the output end of the coding module is connected to the input end of the laser driving module via the optical wavelength division multiplexing module, and the output end of the laser driving module is connected to the input end of the laser; the output end of the light detector is connected to the input end of the optical wavelength decomposition multiplexing module via the signal processing module, the output end of the optical wavelength decomposition multiplexing module is connected to the input end of the decoding module, and the output end of the decoding module is connected to the service interface module; the optical antenna includes a receiving lens and a transmitting lens; the transmitting lens is connected to the output end of the laser through an optical fiber; the receiving lens is connected to the input end of the light detector through an optical fiber. The tracking detector includes a CCD camera and a four-quadrant detector.

[0021] The ground wireless terminal 1 and the airborne wireless terminal 2 perform wireless communication and positioning flight control via laser, and both the ground wireless terminal 1 and the airborne wireless terminal 2 have laser transceiver functions.

[0022] The front panel of the ground wireless terminal is as follows Figure 2 As shown in FIG. 1 , the front panel of the airborne wireless terminal is composed of a communication transmission window 3, a communication reception window 4, a tracking detection window 5, and a command transmission window 6. Figure 2 As shown, it is composed of a communication transmission window 3, a communication receiving window 4, a tracking and detection window 5, and a command receiving window 6.

[0023] Optical transceiver Figure 3 As shown, it includes a coding module, an optical wavelength division multiplexing module, a laser driving module, a laser, a light detector, a signal processing module, an optical wavelength division multiplexing module, a decoding module and a service interface module. The input end of the coding module is connected to the service interface module, the output end of the coding module is connected to the input end of the laser driving module via the optical wavelength division multiplexing module, and the output end of the laser driving module is connected to the input end of the laser. The output end of the light detector is connected to the input end of the optical wavelength division multiplexing module via the signal processing module, the output end of the optical wavelength division multiplexing module is connected to the input end of the decoding module, and the output end of the decoding module is connected to the service interface module.

[0024] Tracking detectors such as Figure 4 and Figure 5 As shown in the figure, the ground terminal or the airborne terminal immediately starts the closed coarse loop when receiving the beam from the other party. On the one hand, the arrival direction of the incident beam is detected, and the transmitting antenna of the machine is guided to emit a beam in the opposite direction of the incident beam; on the other hand, the servo mechanism of the coarse loop is adjusted to bring the received beam closer to the field of view center of the coarse loop CCD detector, reducing the deviation between the coarse tracking field of view axis and the arrival direction of the incident beam. The digital signal processing circuit of the carrier calculates the deviation angle between the arrival direction of the incident beam and the field of view axis of the machine according to the coordinate position of the received light spot in the local coarse loop detector, and at the same time sends the error correction signal generated by the deviation angle to the stepper motor drive circuit, which controls the stepper motor on the gimbal transmission device, adjusts the pitch and horizontal attitude of the gimbal platform, and guides the antenna visual axis to move in the direction of arrival of the received beam. When the deviation reaches the predetermined coarse and fine tracking conversion threshold, the fine tracking loop is started, and the coarse tracking does not stop. The design of the coarse tracking loop is shown in Figure 4. After the rough tracking is completed, the detector will receive the light spot due to the vibration of the machine body, and in order to suppress such jitter, a fine tracking loop based on a four-quadrant detector is designed. By controlling the large-scale fine aiming mechanism, the deviation between the fine tracking field axis and the direction of arrival of the received light beam is reduced. When the deviation is less than the set error threshold, a signal light is emitted to the other party. Figure 5 As shown in the figure, after the coarse tracking loop is adjusted, the light beam enters the fine tracking loop tracking control. After the light beam passes through the two-dimensional fast tilt mirror (FSM) and the beam splitter, part of the light is irradiated on the signal light detector, and the other part of the light is irradiated on the four-quadrant detector. Then the error processing circuit provides the deviation information between the center of the light spot and the center of the QD detector, which is input into the piezoelectric ceramic PZT driver to drive the two-dimensional fast tilt mirror to deflect, adjust the pitch and horizontal angles of the optical axis, so that the light beam falls on the center of the field of view of the fine tracking detector, complete the fine tracking link, enter the information transmission link, and the two machines can exchange information.

[0025] Optical antennas such as Figure 6As shown, it includes a receiving lens, a transmitting lens, a pitch adjustment knob, a pitch adjustment circuit, a pitch adjustment motor, an azimuth adjustment knob, an azimuth adjustment circuit, an azimuth adjustment motor and a universal adjustment base. The receiving lens and the transmitting lens are mounted on the universal adjustment base. The pitch adjustment knob is connected to the input end of the pitch adjustment circuit, and the output end of the pitch adjustment circuit is connected to the universal adjustment base via the pitch adjustment motor. The azimuth adjustment knob is connected to the input end of the azimuth adjustment circuit, and the output end of the azimuth adjustment circuit is connected to the universal adjustment base via the azimuth adjustment motor. The transmitting lens is connected to the output end of the laser through an optical fiber. The receiving lens is connected to the input end of the light detector through an optical fiber. By adjusting the pitch angle and azimuth angle of the universal adjustment base of the ground wireless terminal 1, the optical antenna of the ground wireless terminal 1 is directed inward toward the direction of the airborne wireless terminal 2; by adjusting the pitch angle and azimuth angle of the universal adjustment base of the airborne wireless terminal 2, the optical antenna of the airborne wireless terminal 2 is directed outward toward the direction of the ground wireless terminal 1; thereby, the laser signals received by the receiving lenses of the communicating parties and the laser signals emitted by the transmitting lenses both reach optimal values.

[0026] The optical terminal, the tracking detector and the optical antenna are coaxial. The real-time position of the UAV is obtained through the tracking detector 5 of the ground wireless terminal 1 and the airborne wireless terminal 2. The front panel of the ground wireless terminal 1 and the front panel of the airborne wireless terminal 2 are rotated and adjusted through the optical antenna so that the laser transceiver directions of the command transmission window 6 of the ground wireless terminal 1 and the command receiving window 6 of the airborne wireless terminal 2 are in the same straight line. Then, the flight instruction is transmitted through the command transmission window 6 of the ground wireless terminal 1, and the command receiving window 6 of the airborne wireless terminal 2 receives the flight instruction. After flying in place according to the instruction, photos are taken. Then, the ground wireless terminal 1 and the airborne wireless terminal 2 are rotated and adjusted by the same method so that the laser transceiver directions of the communication receiving window 4 of the ground wireless terminal 1 and the communication transmission window 3 of the airborne wireless terminal 2 are in the same straight line. The airborne wireless terminal 2 transmits the high-definition photos taken by the camera to the ground wireless terminal 1 through laser signals.

[0027] The present invention utilizes wireless laser control and communication to achieve wireless communication, wireless positioning, and wireless remote control between the UAV and the ground, and can effectively solve the defect that the radio communication in the radio flight control system is easily interfered.

[0028] It should be noted that although the embodiments of the present invention described above are illustrative, they are not intended to limit the present invention, and therefore the present invention is not limited to the above specific embodiments. Without departing from the principles of the present invention, any other embodiments obtained by those skilled in the art under the guidance of the present invention are deemed to be within the protection of the present invention.

Claims

1. An anti-interference wireless laser flight control communication system, characterized in that: It includes a ground wireless terminal and an airborne wireless terminal; the ground wireless terminal is supported by a tripod and placed on the ground; the airborne wireless terminal is suspended on the drone by a drone pod; The ground wireless terminal and the airborne wireless terminal have the same structure, both consisting of an optical transceiver, an optical antenna, and a tracking detector; The optical terminal includes a coding module, an optical wavelength division multiplexing module, a laser driving module, a laser, a light detector, a signal processing module, an optical wavelength division multiplexing module, a decoding module and a service interface module; the input end of the coding module is connected to the service interface module, the output end of the coding module is connected to the input end of the laser driving module via the optical wavelength division multiplexing module, and the output end of the laser driving module is connected to the input end of the laser; the output end of the light detector is connected to the input end of the optical wavelength division multiplexing module via the signal processing module, the output end of the optical wavelength division multiplexing module is connected to the input end of the decoding module, and the output end of the decoding module is connected to the service interface module; The optical antenna comprises a receiving lens and a transmitting lens; the transmitting lens is connected to the output end of the laser through an optical fiber; and the receiving lens is connected to the input end of the light detector through an optical fiber.

2. The anti-interference wireless laser flight control communication system according to claim 1 is characterized in that: The optical antenna further includes a pitch adjustment knob, a pitch adjustment circuit, a pitch adjustment motor, an azimuth adjustment knob, an azimuth adjustment circuit, an azimuth adjustment motor and a universal adjustment base; The receiving lens and the transmitting lens are mounted on a universal adjustment base; The pitch adjustment knob is connected to the input end of the pitch adjustment circuit, and the output end of the pitch adjustment circuit is connected to the universal adjustment base via the pitch adjustment motor; The azimuth adjustment knob is connected to the input end of the azimuth adjustment circuit, and the output end of the azimuth adjustment circuit is connected to the universal adjustment base via the azimuth adjustment motor.

3. The anti-interference wireless laser flight control communication system according to claim 1 is characterized in that: CCD camera coarse tracking and four-quadrant detector fine tracking control.

4. The anti-interference wireless laser flight control communication system according to claim 1 is characterized in that: The optical terminal, tracking detector and optical antenna are coaxial.

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