Ultraviolet light communication system and demodulation method based on transverse effect position sensitive detector

Abstract

The invention discloses an ultraviolet light communication system based on a transverse effect position sensitive detector, and belongs to the technical field of optoelectronic devices. Comprising a space code modulation module, an imaging lens and a signal demodulation module. The spatial coding modulation module is composed of a 2 * 2 high-frequency flicker ultraviolet LED array, a driving circuit and an imaging lens, four LED units are defined as four spatial coding states respectively, information to be transmitted is converted into an 8-bit binary sequence according to an ASCII coding rule, and the 8-bit binary sequence is split into four groups of 2-bit sub-codes; each group of sub-codes realizes information coding based on a two-dimensional space position by controlling the time sequence lightening of a single LED unit; the signal demodulation module comprises a position sensitive detector and a signal processing circuit thereof. The signal processing circuit is configured to restore a binary sub-code corresponding to an incident light spot through a method of comparing amplitude extreme values of four electrode output signals of the position sensitive detector; and then splicing the demodulated sub-codes into a complete data frame. The method is suitable for short-distance ultraviolet light communication in a complex environment.

Description

Technical Field

[0001] This invention belongs to the field of optoelectronic device technology, specifically relating to an ultraviolet light communication system and demodulation method based on a transverse effect position-sensitive detector. Background Technology

[0002] Ultraviolet (UV) optical communication technology, due to its strong anti-interference capability and high confidentiality, has significant application value in military communications, underwater communications, and complex electromagnetic environments. Traditional UV communication systems mostly employ intensity modulation / direct detection (IM / DD) methods, carrying information through changes in light intensity. However, their transmission rate and anti-interference capability are limited by the response characteristics of photodetectors. While existing spatial optical communication schemes based on position-sensitive detectors can decode information through spot position, they still face the following technical bottlenecks: high decoding complexity—traditional four-quadrant position-sensitive detector systems require precise calculation of the spot center coordinates (e.g., through four-quadrant current ratio calculations), which are complex and susceptible to noise interference; insufficient robustness—when the system experiences spot deformation or positional shift due to mechanical vibration, thermal drift, or component aging, coordinate calculation errors significantly reduce decoding reliability; and limited coding efficiency—existing spatial coding schemes mostly employ single spot position mapping, making it difficult to achieve high-density information transmission. Summary of the Invention

[0003] This invention aims to solve the problems of high decoding complexity, insufficient anti-interference capability and low coding efficiency in existing ultraviolet light communication systems. It provides an ultraviolet light communication system and demodulation method based on a position-sensitive detector (PSD). By coordinating the spatial position coding of a 2×2 high-frequency scintillation ultraviolet LED array with the extreme value comparison decoding of the electrical signals output by the four electrodes of the PSD, the complexity of coding and decoding is reduced and the robustness of the optical communication system is enhanced.

[0004] The technical solution adopted in this invention is an ultraviolet light communication system based on a transverse effect position-sensitive detector, characterized in that it includes a spatial coding modulation module, an imaging lens, and a signal demodulation module; The spatial coding modulation module consists of a 2×2 high-frequency scintillation ultraviolet LED array and a driving circuit, and the signal demodulation module includes a position-sensitive detector and a signal processing circuit. The 2×2 high-frequency scintillation ultraviolet LED array is driven by a driving circuit and is placed at the front end of the imaging lens; the position-sensitive detector is electrically connected to the signal processing circuit; the position-sensitive detector includes a geometrically symmetrically distributed position-sensitive working area and four independent electrodes symmetrically arranged at the four corners of the position-sensitive working area. A high-frequency scintillation light source from a 2×2 high-frequency scintillation ultraviolet LED array is projected onto the position-sensitive working area of ​​the position-sensitive detector. The incident beam of the high-frequency scintillation light source forms a light spot on the surface of the position-sensitive detector. Based on the transverse photoelectric effect, the magnitude of the electrical signal generated by each independent electrode, the position of the light spot's intensity centroid, and the Euclidean distance between each independent electrode are negatively correlated. The independent electrode closest to the light spot's intensity centroid generates the largest amplitude electrical signal. By comparing the extreme values ​​of the output signals of the four independent electrodes, the quadrant in which the light spot's intensity centroid is located can be directly identified without calculating the absolute coordinates of the light spot. The signal processing circuit is configured to reconstruct the binary sub-code corresponding to the incident light spot by comparing the amplitude extreme values ​​of the output signals of the four electrodes of the position-sensitive detector, and then splice the demodulated sub-code into a complete data frame.

[0005] Furthermore, the spatial positions of the 2×2 high-frequency flashing ultraviolet LED array are mapped to four binary encoding states: 00, 01, 10, and 11. The driving circuit converts the information to be transmitted into an 8-bit binary sequence according to the ASCII encoding rules and splits it into four groups of 2-bit sub-codes. Each group of sub-codes controls the timing of lighting up a single LED unit to achieve information encoding based on two-dimensional spatial position.

[0006] Furthermore, the working area of ​​the position-sensitive detector is divided into four quadrants, with the center of the position-sensitive detector as the origin of the coordinate system. The four independent electrodes are diagonally symmetrically distributed, specifically: the first electrode and the third electrode are located on the diagonal lines of the first and third quadrants; the second electrode and the fourth electrode are located on the diagonal lines of the second and fourth quadrants.

[0007] Furthermore, the four binary encoding states of the 2×2 high-frequency flashing ultraviolet LED array correspond as follows: LEDs in the first quadrant correspond to 00, LEDs in the second quadrant correspond to 01, LEDs in the third quadrant correspond to 10, and LEDs in the fourth quadrant correspond to 11.

[0008] Furthermore, the driving circuit is configured such that only one high-frequency flashing light source, i.e., the LED unit, emits light at any given time, while the other LED units remain off; the timing relationship of the duration of the light spot signal of a single LED unit satisfies: tp>tr, where tp is the duration of a single LED being lit, and tr is the response time of the position-sensitive detector.

[0009] Furthermore, the optical axis of the imaging lens is coaxial with the center of the 2×2 high-frequency scintillation ultraviolet LED array and the center of the position-sensitive detector, and the imaging lens images the light signal of the light-emitting LED onto the photosensitive area of ​​the position-sensitive detector.

[0010] Furthermore, the position-sensitive working area is a position-sensitive photosensitive area, which is composed of a substrate and a position-sensitive material disposed on the upper surface of the substrate, and the position-sensitive material is in electrical contact with the substrate.

[0011] Furthermore, the signal processing circuit includes: Signal conversion module: used to convert the current signal output by the four electrodes of the position-sensitive detector into a voltage signal, the signal conversion module including a transimpedance amplifier circuit; Channel identification module: connected to the signal conversion module, used to identify the maximum amplitude of the voltage signal of each channel through the voltage comparator array, and determine the electrode channel corresponding to the incident light spot; Data demodulation module: connected to the channel identification module, used to restore the corresponding binary subcode according to the identified electrode channel; Data frame reconstruction module: connected to the data demodulation module, used to concatenate the demodulated binary subcodes into a complete data frame.

[0012] The demodulation method for an ultraviolet communication system based on a transverse effect position-sensitive detector includes the following steps: (1) Data encoding and modulation: The ASCII encoded information to be transmitted is converted into an 8-bit binary sequence and divided into 4 groups of subcodes in groups of 2 bits each; the 2×2 high-frequency flashing ultraviolet LED array is controlled by the driving circuit so that each group of subcodes lights up a single LED unit in a preset quadrant, wherein: The first quadrant LED being lit indicates subcode 00; The second quadrant LED being lit indicates subcode 01; The LED in the third quadrant is lit, indicating subcode 10; The fourth quadrant LED being lit indicates subcode 11; (2) Optical signal transmission and imaging: The optical signal of the light-emitting LED is focused onto the photosensitive area of ​​the position-sensitive detector through the coaxial imaging lens, forming a dynamic light spot corresponding to the spatial position of the LED; (3) Position demodulation: The output current signal of the four electrodes of the position-sensitive detector is acquired by the signal processing circuit, and converted into a voltage signal after transimpedance amplification; the maximum value of the voltage amplitude of each channel is identified by the extreme value comparison method to determine the quadrant where the center of gravity of the light spot is located. (4) Data decoding and reconstruction: The binary subcode is restored according to the mapping relationship between the position of the light spot quadrant and the subcode, and the four subcodes are spliced ​​into a complete 8-bit data frame according to the timing.

[0013] Furthermore, the configuration of the imaging lens and the position-sensitive detector satisfies the following: the centroids of the light intensity of the four light spots formed on the position-sensitive detector after imaging by the 2×2 high-frequency scintillation ultraviolet LED array are located in four different quadrants.

[0014] Compared with the prior art, the present invention has the following advantages: 1. Highly efficient decoding: The spot quadrant is identified by the extreme value comparison method, eliminating the need to calculate absolute coordinates, significantly reducing computational complexity and improving response speed; 2. Robust Design: During system operation, factors such as manufacturing tolerances, thermal drift, and aging of components like the LED array, imaging lens, and position-sensitive detector, or mechanical vibrations, can cause changes in the relative pose of the components, further altering the size, shape, intensity distribution, and relative position of the light spots imaged on the position-sensitive detector. As long as the center of gravity of each imaging spot remains within the four quadrants corresponding to the position-sensitive detector, the system can still maintain accurate decoding of the encoded information, making it suitable for reliable data transmission in military communications, underwater detection, and complex electromagnetic environments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an ultraviolet light communication system based on a transverse effect position-sensitive detector proposed in this invention.

[0016] Figure 2 This is a schematic diagram of the position-sensitive detector proposed in this invention.

[0017] Figure 3 In Example 1, when the light spot illuminates different photosensitive areas of the position-sensitive detector, each electrode outputs a two-dimensional distribution map.

[0018] Figure 4 This represents the optical communication state corresponding to the emission of each unit in the 2×2 high-frequency flashing ultraviolet LED array in Example 1.

[0019] Figure 5 This is an example of optical communication transmission of the text SiCPSD to be transmitted, as described in Example 1. Detailed Implementation

[0020] Various exemplary embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The descriptions of the exemplary embodiments are merely illustrative and are in no way intended to limit the present disclosure or its application or use. The present disclosure may be implemented in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that the present disclosure will be thorough and complete, and will fully express the scope of the disclosure to those skilled in the art. It should be noted that, unless specifically stated otherwise, the relative arrangement of components and steps, the composition of materials, numerical expressions, and values ​​set forth in these embodiments should be interpreted as exemplary only and not as limiting.

[0021] In this disclosure, when a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other devices without an intermediary device, or it may be not directly connected to the other devices but have an intermediary device.

[0022] To better understand the present invention, the following embodiments further illustrate the content of the present invention, but the content of the present invention is not limited to the following embodiments.

[0023] This is a schematic diagram of an ultraviolet communication system based on a transverse effect position-sensitive detector proposed in this invention. It includes an LED driving circuit 1, a 2×2 high-frequency scintillation ultraviolet LED array 2 with an independent structure, an imaging lens 3, a position-sensitive detector 4, and a signal processing circuit 5. The 2×2 high-frequency scintillation ultraviolet LED array 2 is driven by the LED driving circuit 1 and is positioned in front of the imaging lens 3, projecting the entire 2×2 high-frequency scintillation ultraviolet LED array 2 onto the working area of ​​the position-sensitive detector 4. The position-sensitive detector 4 is electrically connected to the signal processing circuit 5.

[0024] Since this embodiment mainly introduces the ultraviolet light communication system and demodulation method, rather than the specific driving circuit and signal processing circuit, the specific circuit structure and technical route are not described. Instead, a circuit performance requirement applicable to this system is proposed. Example

[0025] An ultraviolet (UV) optical communication system and demodulation method based on a transverse effect position-sensitive detector are disclosed. The UV communication system mainly includes a position-sensitive detector, whose structure, from bottom to top, comprises a lower electrode, a substrate, a position-sensitive material, and four independent upper electrodes symmetrically arranged at the four corners of the working area. The position-sensitive material is placed on the upper surface of the substrate and forms electrical contact with it. The four independent electrodes form electrical contact with the position-sensitive material, and the lower electrode forms electrical contact with the substrate. Both the substrate and the position-sensitive material are silicon carbide. The substrate is a conductive silicon carbide substrate, and the position-sensitive material includes p-type and n-type silicon carbide position-sensitive materials formed by doping or epitaxy. The upper and lower electrodes are at least one metal selected from nickel, titanium, aluminum, and gold. The diameter or side length of each upper electrode ranges from 10 μm to 500 μm, and the lower electrode adopts a full-coverage approach. The bias voltage applied to the four independent upper and lower electrodes ranges from 0 mV to 20 V. The position-sensitive detector prepared in this embodiment has a fast light response time, that is, the voltage or current signal of the position-sensitive detector reaches its peak value within 10 ms after being illuminated.

[0026] The position-sensitive detector fabricated or selected in this embodiment needs to respond to high-frequency ultraviolet LED light signals and requires a fast light response time. The timing relationship is: tp > tr, where tp is the lighting duration of a single LED unit and tr is the detector response time. Therefore, to achieve this, the position-sensitive detector is designed (including the structure of the position-sensitive detector and the material properties of the position-sensitive area) to have good ultraviolet light response capability and a fast light response time. Since this embodiment mainly introduces the ultraviolet light communication system and demodulation method, rather than introducing specific driving circuits and signal processing circuits for position detection devices, the specific device structure, material properties, and physical mechanisms are not described in detail. Only a device performance requirement suitable for this detection method is proposed.

[0027] A high-frequency scintillation light source is prepared or selected, which consists of an array of four independent and controllable LED units, forming a 2×2 high-frequency scintillation ultraviolet LED array. At any given time, only one LED unit emits light, while the others remain off. In this embodiment, the scintillation frequency of the LED units is 50Hz. The spatial positions of the 2×2 high-frequency scintillation ultraviolet LED array are mapped to four binary coded states: 00, 01, 10, and 11. The switching, pointing, and light intensity are controlled according to the importance, purpose, and type characteristics of the target being detected. This high-frequency scintillation light source can be an independent structure or placed on the target being tested. It can also be a light source reflected from the surface of the object being tested. The LED units can be replaced by a laser light source.

[0028] An imaging system is prepared or selected to project a complete 2×2 high-frequency scintillation ultraviolet LED array onto the working area of ​​a high-speed position-sensitive detector. The imaging lens employs a coaxial optical design, with its optical axis coaxial with the geometric center of the 2×2 high-frequency scintillation ultraviolet LED array and the center of the photosensitive surface of the position-sensitive detector. This ensures that the light signals from each LED unit are accurately imaged onto a predetermined area of ​​the position-sensitive detector. After optical imaging, the corresponding light spots formed by each LED unit on the photosensitive surface of the position-sensitive detector have their intensity centroids located in four different quadrants of the working area of ​​the position-sensitive detector.

[0029] The driving circuit converts the information to be transmitted into an 8-bit binary sequence according to the ASCII encoding rules, and then divides it into four groups of 2-bit sub-codes. Each group of sub-codes controls the timing of the illumination of a single LED unit to achieve information encoding based on two-dimensional spatial position. Wherein: The first quadrant LED being lit indicates subcode 00; The second quadrant LED being lit indicates subcode 01; The LED in the third quadrant is lit, indicating subcode 10; The fourth quadrant LED being lit indicates subcode 11; The signal processing circuit includes: a signal conversion module for converting the current signal output from the four electrodes of the position-sensitive detector into a voltage signal, the signal conversion module including a transimpedance amplifier circuit; a channel identification module connected to the signal conversion module for identifying the maximum amplitude of the voltage signal of each channel through a voltage comparator array and determining the electrode channel corresponding to the incident light spot; a data demodulation module connected to the channel identification module for restoring the corresponding binary subcode according to the identified electrode channel; and a data frame reconstruction module connected to the data demodulation module for splicing the demodulated binary subcode into a complete data frame. Example

[0030] In this embodiment, the position-sensitive detector is as follows: Figure 2 As shown, a silicon carbide-based high-speed position-sensitive detector with a chip area of ​​6.5 mm × 6.5 mm is used. It mainly includes: a pincushion-shaped position-sensitive area 6; a first electrode 7 and a third electrode 9 located diagonally in the first and third quadrants; and a second electrode 8 and a fourth electrode 10 located diagonally in the second and fourth quadrants. The working area of ​​the position-sensitive detector is divided into four quadrants, with the detector center as the origin, and the horizontal and vertical directions as the x-axis and y-axis of the xoy coordinate system, respectively. The area enclosed by the boundary of the photosensitive area and the x-axis and y-axis, respectively, is the specific region of the quadrant, as shown below. Figure 2 The area enclosed by the dashed line is the fourth quadrant (Q4) of the position-sensitive detector. Similarly, the first (Q1), second (Q2), and third quadrants (Q3) can be defined.

[0031] Based on the transverse photoelectric effect, the magnitude of the electrical signal generated by each electrode of the position-sensitive detector is negatively correlated with the position of the centroid of the light spot intensity and the Euclidean distance between the electrodes. The electrode closest to the centroid of the light spot intensity generates the largest amplitude electrical signal. When the light spot illuminates different positions within the position-sensitive area 6, the first electrode 7, the second electrode 8, the third electrode 9, and the fourth electrode 10 will output different electrical signals according to the different positions of the light spot centroid. The normalized output electrical signal distribution of each electrode is shown below. Figure 3As shown, under standard 275nm LED illumination intensity (1mW / cm²) and 0V bias conditions, the electrode output signals corresponding to the light spots in each quadrant were measured. The normalized output of each electrode of the position-sensitive detector exhibits good uniformity. The magnitudes of the normalized output electrical signals of each electrode are distributed in concentric arcs around the electrode. This further demonstrates that the magnitudes of the normalized output signals of each electrode of the position-sensitive detector are linearly related to the centroid of the light spot and the distance between each electrode. Therefore, it can be reasonably deduced that when the centroid of the beam falls in the first quadrant, the first electrode 7 outputs the largest electrical signal; similarly, when the centroid of the beam falls in the second, third, and fourth quadrants respectively, the second electrode 8, the third electrode 9, and the fourth electrode 10 output the largest electrical signals.

[0032] Therefore, by determining the electrode where the maximum value of the output signal of the first electrode 7, the second electrode 8, the third electrode 9, and the fourth electrode 10 of the position-sensitive detector is located, the specific quadrant position of the light spot in the position-sensitive area 6 can be resolved without calculating the specific position, thereby realizing optical communication based on the position-sensitive detector.

[0033] In this embodiment, the optical communication states corresponding to the emission of each unit of the 2×2 high-frequency flickering ultraviolet LED array are as follows: Figure 4 As shown. Here, the first quadrant LED illumination represents subcode 00, the second quadrant LED illumination represents subcode 01, the third quadrant LED illumination represents subcode 10, and the fourth quadrant LED illumination represents subcode 11; the imaging lens 3 projects the light beams generated by the first, second, third, and fourth quadrant LEDs completely onto the Q1, Q2, Q3, and Q4 quadrants of the position-sensitive detector 4's position-sensitive area 6; furthermore, the maximum values ​​of the signals output by each electrode in the position-sensitive detector 4 are generated at the first electrode 7, the second electrode 8, the third electrode 9, and the fourth electrode 10, respectively.

[0034] like Figure 5As shown, the proposed method and embodiments of this invention will be further elaborated with the text to be transmitted, SiCPSD, as the target. First, taking S as an example, the driving circuit 1 first converts S into an 8-bit binary sequence 01010011 according to the ACSII encoding rules, and then splits it into four groups of 2-bit sub-codes: 01, 01, 00, and 11. Each group of sub-codes controls the timing of the lighting of a single LED unit in the 2×2 high-frequency flashing ultraviolet LED array, that is, lighting the second, second, first, and fourth quadrant LEDs sequentially. The imaging lens 3 projects the light beams generated sequentially by the second, third, first, and fourth quadrant LED units completely onto the Q2, Q3, Q1, and Q4 quadrants in the position-sensitive detector 4's position-sensitive area 6. Furthermore, the maximum values ​​of the signals output by each electrode in the position-sensitive detector 4 are generated at the second electrode 8, the third electrode 9, the first electrode 7, and the fourth electrode 10, respectively. Next, the signal conversion module in signal processing circuit 5 converts the current signals output from the first electrode 7, second electrode 8, third electrode 9, and fourth electrode 10 in the position-sensitive detector 4 into voltage signals. Then, the voltage comparator array in signal processing circuit 5 identifies the maximum values ​​of the voltage signals from the channels of the first electrode 7, second electrode 8, third electrode 9, and fourth electrode 10, which originate from the second electrode 8, third electrode 9, first electrode 7, and fourth electrode 10, respectively, thereby determining that the incident light spot is located in quadrants Q2, Q3, Q1, and Q4 of the position-sensitive area 6 of the position-sensitive detector 4. Subsequently, the data demodulation module restores the corresponding binary subcode and splices together a complete data frame 01010011 to realize the transmission of information S. Similar optical communication transmission examples in SiCPSD and iCPSD can also be found from... Figure 4 Obtained from.

[0035] The embodiments of this disclosure have now been described in detail. To avoid obscuring the concept of this disclosure, some details known in the art have not been described. Those skilled in the art can fully understand how to implement the technical solutions disclosed herein based on the above description.

[0036] While specific embodiments of this disclosure have been described in detail by way of examples, those skilled in the art should understand that the examples are for illustrative purposes only and not intended to limit the scope of this disclosure. Those skilled in the art should understand that modifications can be made to the above embodiments or equivalent substitutions can be made to some technical features without departing from the scope and spirit of this disclosure. The scope of this disclosure is defined by the appended claims.

Claims

1. An ultraviolet optical communication system based on a transverse effect position-sensitive detector, characterized in that: Includes a spatial coding modulation module, an imaging lens, and a signal demodulation module; The spatial coding modulation module consists of a 2×2 high-frequency scintillation ultraviolet LED array and a driving circuit, and the signal demodulation module includes a position-sensitive detector and a signal processing circuit. The 2×2 high-frequency scintillation ultraviolet LED array is driven by a driving circuit and is placed at the front end of the imaging lens. The position-sensitive detector is electrically connected to the signal processing circuit; the position-sensitive detector includes a geometrically symmetrically distributed position-sensitive working area and four independent electrodes symmetrically arranged at the four corners of the position-sensitive working area; A high-frequency scintillation light source from a 2×2 high-frequency scintillation ultraviolet LED array is projected onto the position-sensitive working area of ​​the position-sensitive detector. The incident beam of the high-frequency scintillation light source forms a light spot on the surface of the position-sensitive detector. Based on the transverse photoelectric effect, the magnitude of the electrical signal generated by each independent electrode, the position of the light spot's intensity centroid, and the Euclidean distance between each independent electrode are negatively correlated. The independent electrode closest to the light spot's intensity centroid generates the largest amplitude electrical signal. By comparing the extreme values ​​of the output signals of the four independent electrodes, the quadrant in which the light spot's intensity centroid is located can be directly identified without calculating the absolute coordinates of the light spot. The signal processing circuit is configured to reconstruct the binary sub-code corresponding to the incident light spot by comparing the amplitude extreme values ​​of the output signals of the four electrodes of the position-sensitive detector, and then splice the demodulated sub-code into a complete data frame.

2. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 1, characterized in that: The spatial positions of the 2×2 high-frequency flashing ultraviolet LED array are mapped to four binary encoding states: 00, 01, 10, and 11. The driving circuit converts the information to be transmitted into an 8-bit binary sequence according to the ASCII encoding rules and splits it into four groups of 2-bit sub-codes. Each group of sub-codes controls the timing of lighting up a single LED unit to achieve information encoding based on two-dimensional spatial position.

3. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 2, characterized in that: The working area of ​​the position-sensitive detector is divided into four quadrants. Each quadrant has the center of the position-sensitive detector as the origin of the coordinate system. The four independent electrodes are diagonally symmetrically distributed, specifically: the first electrode and the third electrode are located on the diagonal lines of the first and third quadrants; the second electrode and the fourth electrode are located on the diagonal lines of the second and fourth quadrants.

4. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 3, characterized in that, The four binary encoding states of the 2×2 high-frequency flashing ultraviolet LED array correspond as follows: LEDs in the first quadrant correspond to 00, LEDs in the second quadrant correspond to 01, LEDs in the third quadrant correspond to 10, and LEDs in the fourth quadrant correspond to 11.

5. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 1, characterized in that: The driving circuit is configured such that only one high-frequency flashing light source, i.e., the LED unit, is lit at any given time, while the other LED units remain off. The timing relationship of the duration of the light spot signal of a single LED unit satisfies: tp > tr, where tp is the duration of a single LED being lit, and tr is the response time of the position-sensitive detector.

6. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 1, characterized in that: The optical axis of the imaging lens is coaxial with the center of the 2×2 high-frequency scintillation ultraviolet LED array and the center of the position-sensitive detector. The imaging lens images the light signal of the light-emitting LED onto the photosensitive area of ​​the position-sensitive detector.

7. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 1, characterized in that: The position-sensitive working area is a position-sensitive photosensitive area, which consists of a substrate and a position-sensitive material disposed on the upper surface of the substrate, and the position-sensitive material is in electrical contact with the substrate.

8. The ultraviolet light communication system based on a transverse effect position-sensitive detector according to claim 1, characterized in that: The signal processing circuit includes: Signal conversion module: used to convert the current signal output by the four electrodes of the position-sensitive detector into a voltage signal, the signal conversion module including a transimpedance amplifier circuit; Channel identification module: connected to the signal conversion module, used to identify the maximum amplitude of the voltage signal of each channel through the voltage comparator array, and determine the electrode channel corresponding to the incident light spot; Data demodulation module: connected to the channel identification module, used to restore the corresponding binary subcode according to the identified electrode channel; Data frame reconstruction module: connected to the data demodulation module, used to concatenate the demodulated binary subcodes into a complete data frame.

9. A demodulation method for implementing an ultraviolet light communication system based on a transverse effect position-sensitive detector as described in any one of claims 1-8, characterized in that, Includes the following steps: (1) Data encoding and modulation: The ASCII encoded information to be transmitted is converted into an 8-bit binary sequence and divided into 4 groups of subcodes in groups of 2 bits each; the 2×2 high-frequency flashing ultraviolet LED array is controlled by the driving circuit so that each group of subcodes lights up a single LED unit in a preset quadrant, wherein: The first quadrant LED being lit indicates subcode 00; The second quadrant LED being lit indicates subcode 01; The LED in the third quadrant is lit, indicating subcode 10; The fourth quadrant LED being lit indicates subcode 11; (2) Optical signal transmission and imaging: The optical signal of the light-emitting LED is focused onto the photosensitive area of ​​the position-sensitive detector through the coaxial imaging lens, forming a dynamic light spot corresponding to the spatial position of the LED; (3) Position demodulation: The output current signal of the four electrodes of the position-sensitive detector is acquired by the signal processing circuit, and converted into a voltage signal after transimpedance amplification; the maximum value of the voltage amplitude of each channel is identified by the extreme value comparison method to determine the quadrant where the center of gravity of the light spot is located. (4) Data decoding and reconstruction: The binary subcode is restored according to the mapping relationship between the position of the light spot quadrant and the subcode, and the four subcodes are spliced ​​into a complete 8-bit data frame according to the timing.

10. The demodulation method for an ultraviolet optical communication system based on a transverse effect position-sensitive detector according to claim 9, characterized in that: The configuration of the imaging lens and the position-sensitive detector satisfies the following: the centroids of the light intensity of the four light spots formed on the position-sensitive detector after imaging by the 2×2 high-frequency scintillation ultraviolet LED array are located in four different quadrants.

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