Full-view-angle multi-user optical wireless communication system and method based on optical antenna

Abstract

The present invention discloses a full-view multi-user optical wireless communication system and method based on an optical antenna. The system includes a base station and a user terminal; the user terminal includes user transceivers located at different positions; the base station can exchange data with multiple user terminals at the same time; the base station includes: a base station signal sending module, an omnidirectional LD ​​transmitter module, an omnidirectional view angle optical antenna module, a base station receiver, and a base station signal processing module. The present invention can achieve 360-degree full view angle coverage, and has multi-user wireless optical signal transmission capability and regional orientation estimation function.

Description

Technical Field

[0001] The present invention relates to the technical field of optical wireless communication, and in particular to a full-viewing angle multi-user optical wireless communication system and method based on an optical antenna. Background Art

[0002] Optical Wireless Communication (OWC) is an optical communication technology that uses light waves to transmit information in free space, mainly using infrared or visible light to transmit data. Optical wireless communication technology has been used as early as the 20th century, such as free-space laser communication. In recent years, with the popularization of green, efficient, and low-cost LED lighting and the increasing shortage of wireless spectrum resources, optical wireless communication has become an emerging wireless communication method. Compared with traditional radio frequency communication based on electromagnetic waves, OWC technology has many advantages such as richer spectrum resources, stronger security, immunity to electromagnetic interference, no need for spectrum licenses, and green and efficient. However, OWC technology also faces challenges in the application process, such as the need to maintain line of sight. If the light is not aligned or blocked, the link will be interrupted, so maintaining link stability is a technical problem.

[0003] In the field of radio frequency communications, antennas are key components in communication systems and are used to transmit and receive signals. The design of antennas directly affects the efficiency, coverage, and quality of communications. In the field of optical wireless communications, traditional optical devices are generally used as antennas. These devices usually include lenses, reflectors, and fiber coupling devices to focus or transmit optical signals. However, traditional optical antennas have some limitations. For example, the fixed optical design leads to high requirements for optical path alignment, and a slight deviation may lead to signal loss. In addition, due to the limitations of optical etendue conservation, traditional antennas have limited field of view and cannot effectively enhance signals, which makes it difficult to ensure communication quality in weak signals or complex environments.

[0004] As an innovative technology, optical antennas based on photoluminescent materials can re-emit optical signals after receiving them, breaking through the optical extension conservation limitation of traditional optical antennas and achieving large-area and wide-angle communication at the receiving end. This feature eliminates the need for precise alignment of the receiving end with the transmitting end, improving the flexibility and reliability of communication. The photoluminescent materials in optical antennas can absorb light signals incident from a wide field of view angle, convert them and re-emit them, and use a special optical waveguide structure to achieve the effect of focusing the received light onto the detector's photosensitive surface. Even in the case of weak signals, the characteristics of photoluminescent materials can enhance the received signal and ensure communication stability.

[0005] Existing optical wireless communication systems are limited by the line-of-sight propagation characteristics of optical signals and the field of view of the receiver, and are mostly used for point-to-point communication. When it comes to multiple users communicating with the base station at the same time, how the base station receives optical signals from different directions is a difficult point. This scenario requires the base station receiver to have a wider and larger receiving field of view to achieve 360-degree coverage without blind spots as much as possible. The existing solution uses multiple receivers, which are large and costly, resulting in limited application scenarios of the existing solution.

[0006] In order to solve the problem of multiple users communicating at the same time, multiple access modulation technology is often used to achieve optical wireless communication without interference between multiple users. Frequency division multiple access is a classic multiple access technology that divides the communication channel into multiple frequency sub-bands and allocates an independent frequency bandwidth to each user to achieve multi-user simultaneous communication. Therefore, how to combine frequency division multiple access technology with optical antennas to apply this technology to multi-user optical wireless communication is a feasible direction for the development of multi-user optical wireless communication technology. Summary of the invention

[0007] The present invention provides a full-field-of-view multi-user optical wireless communication system and method based on an optical antenna, which achieves 360-degree full-field-of-view coverage and has multi-user wireless optical signal transmission capabilities and regional orientation estimation functions, providing convenience for complex multi-user scenario applications of optical wireless communication.

[0008] The technical solution of the present invention is as follows:

[0009] A full-view angle multi-user optical wireless communication system based on an optical antenna, comprising a base station and a user terminal;

[0010] The user terminal includes user transceivers located at different locations; the base station can exchange data with multiple user terminals at the same time;

[0011] The base station comprises:

[0012] The base station signal sending module modulates the original signal to be sent to generate a digital signal;

[0013] The omnidirectional LD ​​transmitter module includes a driving power supply and a plurality of LD lamps, wherein the plurality of LD lamps are arranged into a ring-shaped omnidirectional LD ​​transmitting array capable of transmitting optical signals 360 degrees around the base station; the digital signal generated by the signal transmission module is modulated onto the LD lamp and transmitted in the form of an optical signal;

[0014] An omnidirectional field of view optical antenna module, comprising a plurality of optical antennas, each of which has a receiving field of view of not less than 120 degrees, and a plurality of optical antennas arranged in a shape that can realize a 360-degree omnidirectional receiving field of view; used to receive optical signals emitted by a user-end transceiver and transmit them to a receiver;

[0015] A base station receiver, used for receiving the output signal of the omnidirectional field of view optical antenna module and converting it into a digital signal;

[0016] The base station signal processing module is used to demodulate the digital signal generated by the receiver into the source signal corresponding to the user and determine the user's location information.

[0017] The process of base station signal transmission is as follows: the signal transmission module of the base station modulates the encoded signal to be transmitted into a time domain carrier signal; the omnidirectional LD ​​transmitter module uses a driving power supply to drive the LD lamp array to load the modulated signal into the transmitted optical signal, and sends the optical signal to the user transceiver of each user end;

[0018] The process of base station signal reception is as follows: the base station's full-field-of-view optical antenna receives optical signals emitted by user transceivers from different directions, and gathers the optical signals at the receiver; the receiver converts the received optical signals into digital signals and transmits them to the signal processing module; the signal processing module demodulates the digital signals into the source signals of the corresponding users and determines the user's location information.

[0019] Preferably, the user transceiver includes a signal sending module, a user LD transmitter, an optical antenna, a user receiver, and a user signal processing module.

[0020] The optical signal transmitted from the base station is received and converted by the optical antenna and then waveguided to the base station receiver. The collected optical signal is converted into an electrical signal by the base station receiver and then transmitted to the base station signal processing module; the received electrical signal is extracted and demodulated by the base station signal processing module and restored to the user signal.

[0021] The base station mainly completes the functions of optical wireless communication, optical conversion, photoelectric conversion, signal processing and user area azimuth estimation.

[0022] The present invention integrates a full-view-angle optical antenna module in a full-view-angle multi-user optical wireless communication system. Through the module, the base station receiver can receive optical signals from different user transceivers in 360-degree directions, greatly expanding the field of view and receiving area of ​​the receiving end, thereby improving the stability and scalability of the communication system.

[0023] Preferably, the optical antenna is flat, curved, cylindrical or hemispherical.

[0024] Preferably, the full-field-of-view optical antenna module includes three flat-plate optical antennas, which form a hollow triangular prism; the flat-plate optical antenna has a waveguide structure that gathers optical signals to one side of the receiver.

[0025] Preferably, the optical antenna comprises a transparent photocurable matrix and a photoluminescent material encapsulated in the transparent photocurable matrix.

[0026] The optical antenna integrated in the full-viewing angle multi-user optical wireless communication system of the present invention has tunable photoluminescence characteristics, and can adjust the photoluminescent material in the optical antenna according to the needs of optical wireless communication, thereby adjusting its emission wavelength; the luminescence spectrum of the photoluminescent material is in the 400-1200nm band.

[0027] Furthermore, the photoluminescent material is at least one of perovskite quantum dots, II-VI semiconductor quantum dots, IV-VI semiconductor quantum dots, organic luminescent quantum dots, organic luminescent dye molecules, carbon quantum dots, and silicon quantum dots; and the transparent photocurable matrix is ​​polylauryl methacrylate (PLMA).

[0028] After the optical antenna unit absorbs the excitation light, the photoluminescent material therein will generate light of a specific band, which will be waveguided by the waveguide structure to the base station receiver side of the optical antenna, thereby realizing the side collection of the optical signal.

[0029] Preferably, the base station receiver is a one-dimensional detector array composed of a plurality of photoelectric detectors.

[0030] The photoelectric detector is a silicon photoelectric detector.

[0031] The present invention also provides a method for performing full-view-angle multi-user optical wireless communication based on the full-view-angle multi-user optical wireless communication system, comprising:

[0032] (1) Divide the available frequency band into several sub-bands of equal length, each sub-band corresponds to a subcarrier; each two adjacent sub-bands are used as an uplink frequency band and a downlink frequency band respectively; the sub-bands allocated to the user include an uplink frequency band and a downlink frequency band;

[0033] (2) Numbering users according to the order in which their transceivers establish links with the base station; dynamically adjusting the number of sub-bands allocated to each user based on the number of currently connected users and the number of remaining sub-bands as the degree of channel congestion; the number of sub-bands allocated to each user shall not exceed one third of the total number of available frequency bands in the system;

[0034] (3) The process of base station signal transmission is as follows: the signal transmission module of the base station modulates the encoded signal to be transmitted into a time domain carrier signal; the omnidirectional LD ​​transmitter module uses a driving power supply to drive the LD lamp array to load the modulated signal into the transmitted optical signal, and sends the optical signal to the user transceiver of each user end;

[0035] The process of base station signal reception is as follows: the base station full-field-of-view optical antenna receives optical signals emitted by user transceivers from different directions, and gathers the optical signals to the base station receiver; the base station receiver converts the received optical signals into digital signals and transmits them to the base station signal processing module; the base station signal processing module demodulates the digital signals into the source signals of the corresponding users and determines the user location information.

[0036] The full-viewing-angle multi-user optical wireless communication method of the present invention adopts a frequency division multiple access modulation method to realize multi-user data transmission.

[0037] Preferably, the subcarrier signal modulation is quadrature amplitude modulation (QAM); the modulation order of the subcarrier is dynamically adjusted between BPSK and 64-QAM according to different channel conditions.

[0038] In step (2), judging the number of sub-bands to be allocated to new users based on the number of currently connected users and the number of remaining sub-bands as the degree of channel congestion includes: calculating the maximum number of accommodated users based on the total number of allocated sub-bands, dividing the channel congestion degree into several levels based on the proportion of the number of currently connected users, and each level corresponds to a different number of allocated sub-bands.

[0039] The signal processing module performs bandpass filtering on the receiver signal data according to the sub-frequency band range used by the user.

[0040] Preferably, the data frames sent and received between the base station and the user end include a cyclic prefix (CP), a pilot and valid information data; the cyclic prefix is ​​used for signal synchronization; and the pilot is used for signal processing module channel equalization.

[0041] Preferably, the base station divides the two-dimensional 360-degree omnidirectional field of view into regions, determines the two-dimensional spatial direction of the signal source according to the position distribution of the signal received by the base station receiver, and estimates the straight-line distance between the signal source and the base station according to the amplitude of the received signal, thereby estimating the regional orientation of the user terminal.

[0042] Compared with the prior art, the present invention has the following beneficial effects:

[0043] (1) In view of the defects of traditional point-to-point optical wireless communication systems such as limited field of view, easy obstruction, difficult alignment, and few matching scenarios, the full-field-of-view multi-user optical wireless communication system based on optical antennas of the present invention adopts a large-field-of-view optical antenna combination design. The system achieves 360-degree omnidirectional reception field of view signal coverage, effectively increases the receiving area, optimizes the utilization efficiency of divergent optical signals, overcomes the signal blind spot problem and difficulty in alignment caused by the limited field of view in traditional technologies, and greatly improves the signal quality, stability, applicability and coverage capability of the communication system.

[0044] (2) With respect to the traditional single-user optical communication system, the optical antenna-based full-field-of-view multi-user optical wireless communication method of the present invention adopts frequency division multiple access technology to realize unaffected simultaneous communication between the base station and multiple user transceivers. By processing multi-user signals in parallel, the signal processing capability of the system is significantly improved, ensuring the communication stability and efficiency in a multi-user environment.

[0045] (3) The optical wireless communication system of the present invention has a multi-user regional azimuth estimation function, which can calculate and estimate the two-dimensional spatial distribution of multiple users, and can dynamically adjust the corresponding channel equalization algorithm based on the estimation to improve the quality of the received signal. At the same time, it provides a technical basis for multifunctional applications (such as positioning, navigation and data transmission integration), and has broad application prospects.

[0046] (4) The optical wireless communication system of the present invention is adaptable to complex dynamic scenes and can maintain stable communication under conditions such as user movement and numerous obstacles. Compared with the traditional fixed field of view communication system, the present invention has stronger adaptability to scenes in complex environments and can be widely used in indoor and outdoor high-dynamic scenes, Internet of Vehicles, smart homes and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 This is a schematic diagram of the structure of a base station of a full-view angle multi-user optical wireless communication system based on an optical antenna provided in Embodiment 1 of the present invention; (a) is a schematic diagram of the overall structure of the base station, and (b) is a schematic diagram of the bottom structure of the integrated cover plate;

[0048] Figure 2 It is a schematic diagram of the principle of receiving optical signals by a base station of the full-view angle multi-user optical wireless communication system based on an optical antenna of the present invention;

[0049] Figure 3 It is a schematic diagram of the optical signal principle of the user-side receiving system of the full-viewing angle multi-user optical wireless communication system based on the optical antenna of the present invention;

[0050] Figure 4 A schematic diagram of a frequency division multiplexing method for a multi-user optical wireless communication method provided in Embodiment 2 of the present invention;

[0051] in:

[0052] 101: LD transmitter of user 1; 102: LD transmitter of user 2; 103: LD transmitter of user 3; 104: full-field-of-view optical antenna module; 105: base station receiver; 106: base station signal processing module; 201: omnidirectional LD ​​transmitter module; 202: flat-plate optical antenna of user 1; 203: flat-plate optical antenna of user 2; 204: flat-plate optical antenna of user 3; 205: receiver of user 1; 206: receiver of user 2; 207: receiver of user 3; 208: signal processing module of user 1; 209: signal processing module of user 2; 210: signal processing module of user 3. DETAILED DESCRIPTION

[0053] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be pointed out that the embodiments described below are intended to facilitate the understanding of the present invention and do not have any limiting effect on the present invention.

[0054] Example 1

[0055] The optical antenna-based full-viewing angle multi-user optical wireless communication system of the present invention comprises a base station and a plurality of user terminals located at different positions. The base station can exchange data with a plurality of user terminals at the same time.

[0056] The structure of the base station corresponding to this embodiment is as follows Figure 1 As shown, the base station includes: a base 1, an integrated cover 2, a full-viewing angle optical antenna module 104, a base station receiver 105, a base station signal processing module 106, and an omnidirectional LD ​​transmitter module 201.

[0057] The base 1 is used to fix the full-view optical antenna module 104 and other modules. The integrated cover 2 integrates the base station receiver 105. The base station receiver 105 is a photodetector array, which is used to receive the optical signal gathered by the full-view optical antenna module 104. It can effectively utilize the strip-shaped light distribution of the full-view optical antenna module 104, and at the same time, it can use its own array characteristics to determine the spatial information of the optical signal for the azimuth estimation of the area where the user is located.

[0058] The full-view optical antenna module 104 includes three flat optical antenna units, which form a hollow triangular prism. The base 1 and the integrated cover 2 are respectively fixed at the two ends of the hollow triangular prism, and the base station signal processing module 106 is placed in the internal space of the hollow triangular prism. Each flat optical antenna unit can receive an effective receiving field of view of optical signals greater than or equal to 120 degrees. By placing the three in an equilateral triangle position, 360-degree full-view optical signal reception can be achieved while ensuring the signal reception quality, and the optical signal is gathered to one side of the base station receiver 105 using its waveguide structure.

[0059] The omnidirectional LD ​​transmitter module 201 is integrated on the integrated cover plate 2. The omnidirectional LD ​​transmitter module 201 is an omnidirectional LD ​​array, which is used to transmit optical signals in 360 degrees so that the optical signals can be received by every user within the effective range.

[0060] The user end includes an LD transmitter, a user receiver and a user signal processing module.

[0061] This embodiment takes three users as an example to introduce in detail the working process of the full-viewing angle multi-user optical wireless communication system based on optical antennas of the present invention.

[0062] The process of the full-view multi-user optical wireless communication system based on optical antennas is as follows:

[0063] like Figure 2 As shown, the optical signals emitted by the LD transmitter 101 of user 1, the LD transmitter 102 of user 2, and the LD transmitter 103 of user 3 propagate through free space, and are received by the full-field-of-view optical antenna module 104 of the base station for optical conversion, and the optical signals are gathered to the base station receiver 105 by using its waveguide structure. The base station receiver 105 receives the optical signal from the optical antenna and converts it into an electrical signal, and transmits the electrical signal to the base station signal processing module 106; the base station signal processing module 106 demodulates the electrical signal into the source signal of the corresponding user, and determines the user's location area information.

[0064] like Figure 3 As shown, after the optical signal emitted by the omnidirectional LD ​​transmitter module 201 from the base station propagates through the free space, it is received by the flat optical antenna 202 of user 1, the flat optical antenna 203 of user 2, and the flat optical antenna 204 of user 3 for optical conversion, and the optical signal is respectively gathered to the receiver 205 of user 1, the receiver 206 of user 2, and the receiver 207 of user 3 by using their waveguide structures. The receiver 205 of user 1, the receiver 206 of user 2, and the receiver 207 of user 3 receive the optical signal of the optical antenna and convert it into an electrical signal, and transmit the electrical signal to the signal processing module 208 of user 1, the signal processing module 209 of user 2, and the signal processing module 210 of user 3 respectively; the signal processing module 208 of user 1, the signal processing module 209 of user 2, and the signal processing module 210 of user 3 remove redundant information according to the sub-bands allocated to the users, and respectively demodulate the electrical signal into the source signal of the corresponding users.

[0065] Example 2

[0066] This embodiment specifically introduces a full-viewing angle multi-user optical wireless communication method based on an optical antenna, including:

[0067] Step 1: Figure 4As shown, the system divides the available frequency band into several sub-bands of equal length, each sub-band corresponds to a subcarrier, wherein every two adjacent sub-bands serve as an uplink frequency band and a downlink frequency band respectively, and the sub-bands allocated to users include an uplink frequency band and a downlink frequency band.

[0068] Step 2: Number the users according to the order in which the LD transmitter and receiver at the user end establish links with the base station, divide the channel congestion into several levels, divide the total number of allocated sub-bands by the minimum number of sub-bands required by the users to obtain the maximum number of users that can be accommodated, and then dynamically adjust the number of sub-bands allocated to each user based on the proportion of the current number of connected users to determine the channel congestion level. The number of sub-bands allocated to each user shall not exceed one-third of the total number of available bands in the system, to prevent congestion caused by a single user occupying too many sub-bands.

[0069] Step 3: using a real orthogonal frequency division multiple access modulation method to modulate and demodulate multiple frequency band multiplexed subcarrier signals, said step 3 comprising:

[0070] Step 31: The subcarrier signal is modulated to quadrature amplitude modulation (QAM). The modulation order of the subcarrier is dynamically adjusted according to different channel conditions. The modulation order ranges from BPSK to 64-QAM.

[0071] Step 32: Load the subcarrier signal onto the corresponding allocated subband carrier, and establish a Hermitian symmetric matrix based on the loaded subcarrier matrix, which is used to generate a real time domain signal after an inverse Fourier transform (IFFT).

[0072] Step 33: The data frame of the real time domain signal includes a cyclic prefix (CP), a pilot and valid information data, wherein the cyclic prefix is ​​used for signal synchronization, and the pilot is used for channel equalization.

[0073] Step 34: The signal processing module performs finite impulse response (FIR) bandpass filtering on the received signal data according to the sub-band range used by the user, and extracts the sub-carrier signal corresponding to the effective information.

[0074] Step 4: The system divides the two-dimensional 360-degree full field of view into regions, determines the two-dimensional spatial direction of the signal source according to the position distribution of the received signal by the photodetector array, and estimates the straight-line distance between the signal source and the base station according to the amplitude of the received signal, thereby estimating the location area azimuth of the user end.

[0075] The embodiments described above provide a detailed description of the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, supplements and equivalent substitutions made within the scope of the principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A full-view multi-user optical wireless communication system based on an optical antenna, comprising a base station and a user terminal; characterized in that: The user end includes user transceivers located at different locations; The base station can exchange data with multiple user terminals at the same time; The base station comprises: The base station signal sending module modulates the original signal to be sent to generate a digital signal; The omnidirectional LD ​​transmitter module includes a driving power supply and a plurality of LD lamps, wherein the plurality of LD lamps are arranged into a ring-shaped omnidirectional LD ​​transmitting array capable of transmitting optical signals 360 degrees around the base station; the digital signal generated by the signal transmission module is modulated onto the LD lamp and transmitted in the form of an optical signal; An omnidirectional viewing angle optical antenna module, comprising a plurality of optical antennas, each optical antenna receiving a viewing angle of not less than 120 degrees, and the plurality of optical antennas being arranged in a shape that can realize a 360-degree omnidirectional receiving viewing angle; used to receive an optical signal emitted by a user-end transceiver and transmit it to a receiver; the optical antenna comprises a transparent light-curing matrix and a photoluminescent material wrapped in the transparent light-curing matrix; A base station receiver is used to receive the output signal of the omnidirectional field of view optical antenna module and convert it into a digital signal; the base station receiver is a one-dimensional detector array composed of a plurality of photodetectors; the photodetector is a silicon photodetector; The base station signal processing module is used to demodulate the digital signal generated by the base station receiver into the source signal corresponding to the user and determine the user's location information; The full-view multi-user optical wireless communication system adopts a frequency division multiple access modulation method to realize multi-user data transmission; the subcarrier signal modulation is orthogonal amplitude modulation; the modulation order of the subcarrier is dynamically adjusted between BPSK and 64-QAM according to different channel conditions.

2. The full-view angle multi-user optical wireless communication system based on optical antenna according to claim 1, characterized in that: The user transceiver comprises a user signal sending module, a user LD transmitter, an optical antenna, a user receiver and a user signal processing module.

3. The full-view angle multi-user optical wireless communication system based on optical antenna according to claim 1, characterized in that: The photoluminescent material is at least one of perovskite quantum dots, II-VI semiconductor quantum dots, IV-VI semiconductor quantum dots, organic luminescent quantum dots, organic luminescent dye molecules, carbon quantum dots, and silicon quantum dots; and the transparent photocurable matrix is ​​polylauryl methacrylate.

4. A full-view multi-user optical wireless communication method based on an optical antenna, characterized in that: The full-view angle multi-user optical wireless communication system according to any one of claims 1 to 3 is implemented, comprising: (1) Divide the available frequency band into several sub-bands of equal length, each sub-band corresponds to a subcarrier; each two adjacent sub-bands are used as an uplink frequency band and a downlink frequency band respectively; the sub-bands allocated to the user include an uplink frequency band and a downlink frequency band; (2) Numbering users according to the order in which their transceivers establish links with the base station; determining the number of sub-bands to be allocated to each user based on the number of currently connected users and the number of remaining sub-bands as the degree of channel congestion; the number of sub-bands allocated to each user shall not exceed one third of the total number of available frequency bands in the system; (3) The process of base station signal transmission is as follows: the signal transmission module of the base station modulates the encoded signal to be transmitted into a time domain carrier signal; the omnidirectional LD ​​transmitter module uses a driving power supply to drive the LD lamp array to load the modulated signal into the transmitted optical signal, and sends the optical signal to the user transceiver of each user end; The process of base station signal reception is as follows: the base station full-field-of-view optical antenna receives optical signals emitted by user transceivers from different directions, and gathers the optical signals to the base station receiver; the base station receiver converts the received optical signals into digital signals and transmits them to the base station signal processing module; the base station signal processing module demodulates the digital signals into the source signals of the corresponding users and determines the user location information.

5. The full-view multi-user optical wireless communication method according to claim 4, characterized in that: The signal processing module performs bandpass filtering on the receiver signal data according to the sub-frequency band range used by the user.

6. The full-view multi-user optical wireless communication method according to claim 4, characterized in that: The data frames sent and received between the base station and the user end include a cyclic prefix, a pilot and valid information data; the cyclic prefix is ​​used for signal synchronization; the pilot is used for signal processing module channel equalization.

7. The full-view multi-user optical wireless communication method according to claim 4, characterized in that: The base station divides the two-dimensional 360-degree omnidirectional field of view into regions, determines the two-dimensional spatial direction of the signal source according to the position distribution of the signal received by the base station receiver, and estimates the straight-line distance between the signal source and the base station according to the amplitude of the received signal, thereby estimating the regional orientation of the user end.

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