Omnidirectional transmit-receive pan-optical communication system and method for unmanned aerial vehicle group ad hoc network

Abstract

The invention discloses an omni-directional receiving and transmitting pan-optical communication system and method for an unmanned aerial vehicle group ad hoc network. The omni-directional receiving and transmitting pan-optical communication system comprises a main control unit, a power supply unit, a link adaptive unit and N pairs of independent receiving and transmitting bidirectional modulation and demodulation modules. The wide-emission-angle LED light source-based pan-optical communication system is adopted, so that the anti-interference capability of an ad hoc network can be improved, and the difficulty of light path tracking and pointing can be reduced. A multi-beam splicing omnidirectional transceiving design is adopted, a mechanical turntable is not needed, and the load weight and the network delay can be reduced. And each modulation-demodulation module works independently, so that the communication capacity can be expanded, directional confidential transceiving of information is supported, and formation expansion network access is facilitated.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and in particular to an omnidirectional transceiver floodlight communication system and method for a self-organizing network of a swarm of unmanned aerial vehicles. Background Art

[0002] Collaborative drone swarms can significantly improve work efficiency and mission reliability, reducing system costs while increasing system resilience. Implementing self-organizing network communication within drone swarms is fundamental to supporting collaborative work. Self-organizing network communication refers to the process of autonomously connecting drones to establish a wireless mobile network, rather than relying solely on ground control stations or satellite infrastructure. Instead, drones are used as network nodes, automatically connecting to each other.

[0003] Existing drone swarm self-organizing networks primarily rely on microwave and laser communications. However, with the rapid development of electromagnetic interference (EMI) technology and the continuous evolution of new interference methods, such as suppression and deception, drone swarm networks based on microwave links face severe interference. Laser communication offers the advantages of high communication speeds and strong interference resistance, but laser links only enable point-to-point communication. This makes tracking and aiming difficult for small, highly vibrating platforms like drones, and links are prone to breakage.

[0004] Floodlight communication is a communication network technology that uses a light source with a wide emission angle and wide beam coverage to load information into light waves, and uses a photodetector to receive the light signal and demodulate the information. It has the advantages of concealment, anti-interference, simple link establishment, and strong robustness. Patent CN 117728876 A discloses a method and system for floodlight communication for drones, drone swarms, and drone swarms. However, this system obtains the direction of the transmitted light beam through imaging information target identification, and then controls the rotation and adjustment of the pan-tilt platform. This results in a long time to reestablish the communication link and severe network delay when the drone swarm changes position. At the same time, the weight of the two-dimensional pan-tilt platform itself is higher than the weight of the communication payload itself, making it unsuitable for lightweight platforms such as drone swarms. Summary of the Invention

[0005] The technical problem solved by the present invention is: to overcome the shortcomings of the existing technology and provide an omnidirectional transceiver floodlight communication system and method for drone swarm self-organizing networks, so as to solve the problems of existing drone swarm self-organizing network links being susceptible to interference, difficulty in link establishment, easy breakage, slow adjustment of communication load direction, and heavy weight.

[0006] The technical solution of the present invention is to provide an omnidirectional transceiver floodlight communication system for self-organizing networks of drone swarms, including a main control unit, a power supply unit, a link adaptation unit and a communication payload. The communication payload is a floodlight communication payload, which is formed by splicing N pairs of independent transceiver bidirectional modulation and demodulation modules evenly distributed around a central axis, thereby realizing omnidirectional duplex communication between drone swarms without mechanical rotation; each pair of independent transceiver bidirectional modulation and demodulation modules includes a receiving module and a transmitting module, which are separated in an upper and lower configuration; the transmitting light source in the transmitting module is an LED light source, and the signal light divergence angle is 2π / N; the receiving field of view angle of the receiving module is 2π / N.

[0007] Furthermore, the N pairs of independent bidirectional modulation and demodulation modules for transmitting and receiving are jointly encapsulated in a cylindrical shell; the transmitting module includes a transmitting processing submodule, an LED light source and a beam forming lens, and the receiving module includes a converging lens, a photodetector and a receiving processing submodule; wherein, N pieces of beam forming lenses and N pieces of converging lenses are respectively embedded around the shell; N LED light sources are fixed on one side of the shell cavity, and the emitting parts are opposite to each beam forming lens; N photodetectors are fixed on the other side of the shell cavity, and the receiving parts are opposite to each converging lens.

[0008] Furthermore, the receiving module also includes a filter located between the photodetector and the converging lens.

[0009] Furthermore, the transmitting processing submodule converts the information to be transmitted into a driving current, drives the LED light source to emit signal light, and compresses the divergence angle of the signal light to 2π / N through the beam forming lens to transmit the signal light; the converging lens receives the opposite signal light, filters out the light domain noise through the filter, enters the photodetector for photoelectric conversion, and then the receiving processing submodule decodes the information.

[0010] Furthermore, the transmission processing submodule includes a transmission digital signal processing unit and a transmission driving circuit; the reception processing submodule includes a reception processing circuit and a reception digital signal processing unit;

[0011] The transmitting digital signal processing unit generates the required radio frequency signal after encoding the information to be transmitted through a convolutional code error correction. The transmitting driving circuit generates a low-duty-cycle driving current, which causes the LED light source to generate signal light with high peak transmission power; the low duty cycle is 5% to 20%; and the high peak transmission power is 5 to 20 times the average transmission power of the LED light source.

[0012] The opposite signal light is received by a converging lens, filtered out by a narrowband filter for optical domain noise, and then enters a high-sensitivity photodetector for photoelectric conversion. After being filtered out by a receiving processing circuit for electrical domain noise and signal amplification, it enters a receiving digital signal processing unit for information decoding. The narrowband is a bandwidth of 1 to 4 GHz; the high sensitivity is -30 to -40 dBm.

[0013] Furthermore, the transmitting driving circuit adopts the front-stage pre-emphasis technology, and the receiving processing circuit adopts the post-stage equalization technology to improve the communication rate; the link adaptation unit monitors the bit error rate and adaptively adjusts the transmitting module parameters and the receiving module parameters to optimize the system communication quality.

[0014] Furthermore, the transmitting module parameters include communication rate, NRZ coding duty cycle, and front-stage pre-emphasis parameters, and the receiving module parameters include back-stage equalization parameters.

[0015] The present invention also provides an omnidirectional transceiver floodlight communication method for a self-organizing network of a swarm of unmanned aerial vehicles, comprising:

[0016] Each drone is equipped with an omnidirectional transceiver floodlight communication system as claimed in claim 1;

[0017] Each drone acts as the central drone in turn, sending broadcast signals in N directions through an omnidirectional transceiver floodlight communication system, and judging the configuration of the entire drone group through the response sectors of the return signals from the surrounding drones;

[0018] The optimal transmission path is determined based on the configuration of the drone swarm. After mutual identity authentication between two drones, the formation is completed and the drone swarm enters the network, realizing self-organizing networking.

[0019] Furthermore, when there are multiple drones in a single direction, the central drone and the multiple drones in the single direction can communicate without crosstalk through time slot allocation.

[0020] Furthermore, after the drone swarm forms a network, when the formation needs to be expanded, the newly joined drone first searches for an empty bidirectional transceiver modem module in the existing drone's omnidirectional transceiver floodlight communication system through a broadcast mechanism, and then joins the network after mutual identity authentication. If there is no empty bidirectional transceiver modem module in the surrounding area, it agrees on the allocated time slot with the omnidirectional transceiver floodlight communication system with the best communication quality, and then joins the network after mutual identity authentication.

[0021] The advantages of the present invention compared with the prior art are:

[0022] (1) This invention innovatively proposes a floodlight communication system based on a wide-angle LED light source. Compared to microwave communication, it has strong anti-interference and anti-interception capabilities, and compared to laser communication, it has the advantages of easy capture and tracking and multiple access. The design uses multiple pairs of bidirectional transceiver modems to achieve omnidirectional communication in drone swarms without the need for pan-tilt control, reducing payload weight and network latency in drone swarm self-organizing networks.

[0023] (2) Based on the omnidirectional transceiver floodlight communication system proposed in the present invention, the present invention also proposes an omnidirectional transceiver floodlight communication method for drone swarm self-organizing networking, which realizes efficient drone swarm self-organizing networking and better supports free formation expansion.

[0024] (3) The present invention enables multiple pairs of bidirectional modulation and demodulation modules to work independently, thereby improving the system communication capacity based on the space division multiplexing mode, and at the same time, the directional data transmission and reception improves the security and confidentiality of the system.

[0025] (4) The present invention adopts pre-stage pre-emphasis technology, post-stage equalization technology and adaptive channel equalization and compensation technology to optimize the problem of link quality degradation caused by energy attenuation of wide emission angle light sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 This is a front view of the communication payload structure of the present invention;

[0027] Figure 2 A top view of the communication payload structure of the present invention;

[0028] Figure 3 This is a schematic diagram of the composition of each pair of independent transceiver bidirectional modulation and demodulation modules of the present invention;

[0029] Figure 4 This is a schematic diagram of a self-organizing network of a drone group using an omnidirectional transceiver floodlight communication system according to the present invention;

[0030] Figure 1 、 Figure 2 In the middle, 1-1 beam shaping lens, 1-2 LED light source, 1-3 converging lens, 1-4 narrow band filter, 1-5 high sensitivity photodetector, 1-6 housing;

[0031] Figure 3 In the figure, 2-1 main control unit, 2-2 transmitting digital signal processing unit, 2-3 transmitting driving circuit, 1-2 LED light source, 1-1 beam shaping lens, 1-3 converging lens, 1-4 narrowband filter, 1-5 APD avalanche photodiode, 2-7 receiving processing circuit, 2-6 receiving digital signal processing unit, 2-4 power supply unit, 2-5 link adaptation unit. DETAILED DESCRIPTION

[0032] In order to better understand the technical solution of the present invention, the specific embodiments of the present invention are described below. The following description of the preferred embodiments may involve a combination of features, which may exist independently or in combination. The present invention is not particularly limited to the preferred embodiments.

[0033] The present invention provides an omnidirectional transceiver floodlight communication system for unmanned aerial vehicle (UAV) swarm self-organizing network, comprising a main control unit 2-1, a power supply unit 2-4, a link adaptation unit 2-5 and a communication payload.

[0034] The main control unit manages communication data and power-on sequencing; the power supply unit distributes the rated voltage of each electronic component within the payload; and the link adaptation unit adaptively adjusts system parameters to optimize communication quality. Specifically, the communication payload is a floodlight communication payload, composed of N pairs of independent bidirectional transceiver modem modules evenly distributed around a central axis. Each pair includes a separate transmitter and receiver module. The transmitter module uses an LED light source with a signal light divergence angle of 2π / N; the receiver module has a receiving field of view of 2π / N. This enables omnidirectional duplex communication without mechanically rotating parts, reducing the number of payloads required on a single platform, as well as the increased payload weight and network reconfiguration delays caused by mechanical rotation.

[0035] In one possible implementation, Figure 1 and Figure 2 As shown in the figure, the communication payload is composed of 6 pairs of independent transceiver bidirectional modulation and demodulation modules, and the duplex communication in 6 directions is achieved through the structure of isolated transceiver cavity.

[0036] Specifically, 6 pairs of independent bidirectional modulation and demodulation modules for transmitting and receiving are evenly distributed and encapsulated in a cylindrical shell 1-6. 6 beam forming lenses 1-1 and 6 converging lenses 1-3 are embedded in the shell 1-6. The shell can be made of lightweight aluminum alloy material to ensure mechanical performance requirements while reducing the load weight.

[0037] Specifically, the inherent divergence angle of LED light source 1-2 can reach 150°. The beam shaping lens 1-1 compresses the divergence angle to 2π / N, reducing power attenuation caused by beam divergence and increasing communication distance. By splicing six LED light sources, omnidirectional beam emission can be achieved.

[0038] Specifically, the high-sensitivity photodetector uses APD avalanche photodiodes 1-5 to amplify weak light signals. Its detector target surface can be designed to be 5mm×5mm. A parabolic converging lens is used to achieve a receiving field of view of 60°. After passing through converging lenses 1-3, narrowband filters 1-4 perform optical filtering, reducing optical noise caused by solar background light and improving detection sensitivity. By splicing six high-sensitivity photodetectors, omnidirectional light beam reception is possible.

[0039] In one possible implementation, Figure 3 As shown, in the omnidirectional transceiver floodlight communication system, each pair of independent bidirectional transceiver modem modules includes a transmit digital signal processing unit 2-2, a transmit driver circuit 2-3, an LED light source 1-2, a beam shaping lens 1-1, a converging lens 1-3, a narrowband filter 1-4, an APD (Avalanche Photodiode) 1-5, a receive processing circuit 2-7, and a receive digital signal processing unit 2-6. The information transmission process within each pair of independent bidirectional transceiver modem modules is as follows: the transmit digital signal processing unit generates the required RF signal after convolutional error correction encoding of the information to be transmitted. The transmit driver circuit generates a low-duty-cycle drive current, causing the LED light source to generate high-peak transmit power signal light. The beam shaping lens compresses the divergence angle to 60° before the signal light is transmitted. The opposing signal light is received by the converging lens with a wide field of view. After optical noise is filtered by the narrowband filter, it enters a high-sensitivity photodetector for photoelectric conversion of the weak optical signal. After electrical noise is filtered and the signal is amplified by the receive processing circuit, it enters the receive digital signal processing unit for information decoding.

[0040] The main control unit 2 - 1 controls the transmitting digital signal processing unit and the receiving digital signal processing unit to manage communication data, and controls the power supply unit to complete power-on sequence management.

[0041] The power supply units 2-4 adjust the primary power provided by the platform to different voltages through step-down or step-up circuits, respectively providing the required voltages for electronic components such as the transmitting digital signal processing unit, transmitting drive circuit, high-sensitivity photodetector, receiving processing circuit and receiving digital signal processing unit.

[0042] The link adaptation unit 2-5 monitors the system bit error rate and other indicators by receiving the digital signal processing unit, and further controls the transmit drive circuit to adjust the transmitter parameters such as the communication rate, NRZ coding duty cycle, and the front-end pre-emphasis parameters, as well as the receiver parameters such as the back-end equalization parameters, to optimize the link communication quality.

[0043] Preferably, the transmit drive circuit 2-3 can use low-duty-cycle NRZ encoding technology to compress the duration of the high-level action, thereby increasing the signal peak transmit power when the average transmit power is constant, reducing the impact of energy attenuation of wide-angle light sources on link quality degradation and increasing communication distance.

[0044] Preferably, the receiving processing circuit 2-7 can use a high-gain transimpedance amplifier circuit and an electrical filter circuit to filter out DC and low-frequency photocurrent noise, thereby improving the detection sensitivity of the receiving end and increasing the communication distance. At the same time, an automatic gain control circuit is used to adjust the signal amplification factor to solve the problem that high sensitivity causes the receiving end to fail to operate at short distances and high receiving power.

[0045] Preferably, the channel characteristics of the LED light source 1-2 have severe roll-off in the high-frequency part. The transmitting driving circuit adopts the front-stage pre-emphasis technology, which suppresses the low-frequency component and amplifies the high-frequency part in advance at the transmitting end. The receiving processing circuit adopts the post-stage equalization technology to enhance the high-frequency response capability of the receiving end, expand the 3dB bandwidth of the channel, and improve the communication rate.

[0046] Preferably, the transmitting digital signal processing unit 2-2 and the receiving digital signal processing unit 2-6 can adopt error coding control technology. By using (n, k, m) convolutional code for error correction coding and using a probability decoder for decoding, the bit error rate of the digital communication system can be reduced when the signal-to-noise ratio is constant, thereby improving the reliability of the system.

[0047] Preferably, the LED light source 1-2 uses the near-infrared band, which has a stronger ability to penetrate clouds and fog than the visible light band; the spectral component corresponding to sunlight is lower, and the background light interference is smaller; it is invisible to the human eye and can achieve covert communication.

[0048] The present invention also provides an omnidirectional transceiver floodlight communication method for drone swarm self-organizing network, such as Figure 4 As shown, the specific steps include:

[0049] Each drone is equipped with an omnidirectional transceiver floodlight communication system as described above;

[0050] Each drone acts as the central drone in turn, sending broadcast signals in N directions through an omnidirectional transceiver floodlight communication system, and judging the configuration of the entire drone group through the response sectors of the return signals from the surrounding drones;

[0051] The optimal transmission path is determined based on the configuration of the drone swarm. After mutual identity authentication between two drones, the formation is completed and the drone swarm enters the network, realizing self-organizing networking.

[0052] Specifically, N pairs of bidirectional modem modules support independent operation, enabling task-specific information distribution and operational information transmission between drones in specific locations. For example, in an N-sided drone formation, the central drone can send and receive different information with drones in N directions, increasing system communication capacity. Furthermore, directional data transmission and reception enhances system security and confidentiality. When multiple drones are distributed in a single direction, one-to-many communication can be performed in time slots, preventing signal crosstalk caused by multiple receptions.

[0053] Specifically, the drone swarm self-organizing network supports free formation expansion. A newly joined drone first uses a broadcast mechanism to search for a vacant bidirectional modem module in an existing omnidirectional floodlight communication system. After mutual authentication, it joins the network. If no vacant bidirectional modem module exists nearby, it agrees on a time slot with the communication system with the best communication quality, and after mutual authentication, it joins the network.

[0054] Specifically, when the optical path is blocked by obstacles and communication is interrupted, a multi-path relay routing strategy is used to achieve information forwarding and improve the robustness of the network.

[0055] It will be understood that the present invention is described by way of example, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and any embodiment that falls within the scope of the claims of this application is intended to be within the scope of protection of the present invention.

[0056] The contents not described in detail in the specification of the present invention belong to the common knowledge of those skilled in the art.

Claims

1. An omnidirectional transceiver floodlight communication system for drone swarm self-organizing networks, comprising a main control unit, a power supply unit, a link adaptation unit, and a communication payload, characterized by: The communication payload is a floodlight communication payload, which is formed by splicing N pairs of independent transceiver bidirectional modulation and demodulation modules evenly distributed around the central axis to achieve omnidirectional duplex communication between drone groups without mechanical rotation; each pair of independent transceiver bidirectional modulation and demodulation modules includes a receiving module and a transmitting module, which are separated in an upper and lower configuration; the transmitting light source in the transmitting module is an LED light source, and the signal light divergence angle is 2π / N; the receiving field of view angle of the receiving module is 2π / N.

2. The omnidirectional transceiver floodlight communication system for drone swarm ad hoc networking according to claim 1, characterized in that: The N pairs of independent bidirectional modulation and demodulation modules for transmitting and receiving are jointly encapsulated in a cylindrical shell; the transmitting module includes a transmitting processing submodule, an LED light source and a beam forming lens, and the receiving module includes a converging lens, a photodetector and a receiving processing submodule; wherein, N beam forming lenses and N converging lenses are respectively embedded around the shell; N LED light sources are fixed on one side of the shell cavity, with the emitting parts opposite to each beam forming lens; N photodetectors are fixed on the other side of the shell cavity, with the receiving parts opposite to each converging lens.

3. The omnidirectional transceiver floodlight communication system for drone swarm ad hoc networking according to claim 2, characterized in that: The receiving module also includes a filter located between the photodetector and the converging lens.

4. The omnidirectional transceiver floodlight communication system for drone swarm ad hoc networking according to claim 3, characterized in that: The transmitting processing submodule converts the information to be transmitted into a driving current, drives the LED light source to emit signal light, and compresses the divergence angle of the signal light to 2π / N through the beam forming lens to transmit the signal light; the converging lens receives the opposite signal light, filters out the light domain noise through the filter, enters the photoelectric detector for photoelectric conversion, and then the receiving processing submodule decodes the information.

5. The omnidirectional transceiver floodlight communication system for drone swarm ad hoc networking according to claim 4, characterized in that: The transmitting processing submodule includes a transmitting digital signal processing unit and a transmitting driving circuit; the receiving processing submodule includes a receiving processing circuit and a receiving digital signal processing unit; The transmitting digital signal processing unit generates the required radio frequency signal after encoding the information to be transmitted through a convolutional code error correction. The transmitting driving circuit generates a low-duty-cycle driving current, which causes the LED light source to generate signal light with high peak transmission power; the low duty cycle is 5% to 20%; and the high peak transmission power is 5 to 20 times the average transmission power of the LED light source. The opposite signal light is received by a converging lens, filtered out by a narrowband filter for optical domain noise, and then enters a high-sensitivity photodetector for photoelectric conversion. After being filtered out by a receiving processing circuit for electrical domain noise and signal amplification, it enters a receiving digital signal processing unit for information decoding. The narrowband is a bandwidth of 1 to 4 GHz; the high sensitivity is -30 to -40 dBm.

6. The omnidirectional transceiver floodlight communication system for drone swarm ad hoc networking according to claim 5, characterized in that: The transmitting drive circuit adopts the front-stage pre-emphasis technology, and the receiving processing circuit adopts the post-stage equalization technology to improve the communication rate; the link adaptation unit monitors the bit error rate and adaptively adjusts the transmitting module parameters and the receiving module parameters to optimize the system communication quality.

7. The link adaptation subsystem according to claim 6, wherein: The transmitting module parameters include communication rate, NRZ coding duty cycle, and front-stage pre-emphasis parameters, and the receiving module parameters include back-stage equalization parameters.

8. An omnidirectional transceiver floodlight communication method for drone swarm self-organizing network, characterized in that: include: Each drone is equipped with an omnidirectional transceiver floodlight communication system as claimed in claim 1; Each drone acts as the central drone in turn, sending broadcast signals in N directions through an omnidirectional transceiver floodlight communication system, and judging the configuration of the entire drone group through the response sectors of the return signals from the surrounding drones; The optimal transmission path is determined based on the configuration of the drone swarm. After mutual identity authentication between two drones, the formation is completed and the drone swarm enters the network, realizing self-organizing networking.

9. The omnidirectional transceiver floodlight communication method for drone swarm ad hoc networking according to claim 8, characterized in that: When there are multiple drones in a single direction, the central drone and multiple drones in the single direction communicate without crosstalk through time slot allocation.

10. The omnidirectional transceiver floodlight communication method for drone swarm ad hoc networking according to claim 8, characterized in that: After the drone swarm forms a network, when the formation needs to be expanded, the newly joined drone first uses the broadcast mechanism to find an empty bidirectional transceiver modem module in the omnidirectional transceiver floodlight communication system of the existing drone, and then joins the network after mutual identity authentication. If there are no vacant bidirectional transceiver modulation and demodulation modules in the surrounding area, the system will agree on the time slot allocation with the omnidirectional transceiver floodlight communication system with the best communication quality, and join the network after mutual identity authentication.

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