Beaconless optical tracking communication system and its applications

Abstract

The application discloses a beaconless light tracking communication system, comprising a light emitting end and a light receiving end; the light emitting end comprises a laser and a transmitting antenna; the light receiving end comprises a receiving antenna, a fine alignment actuator, a beam splitter, a communication detector and a light spot detector; the laser beam emitted by the laser is received by the receiving antenna after being transmitted by the transmitting antenna, and part of the laser beam enters the communication detector through the beam splitter to realize a communication function, and part of the laser beam enters the light spot detector to realize a light beam alignment tracking function; the light emitting end and / or the light receiving end are provided with a coarse alignment actuator, which is used for controlling the scanning track of the laser beam, so that a light spot appears in the field of view of the light spot detector; the fine alignment actuator controls the pointing of the laser beam, so that the light spot reaches the position of a target center in the light spot detector. The application can solve the problems that the existing beacon APT system has large weight and power consumption, and the beaconless APT system is difficult to quickly complete scanning and accurately capture signals.

Description

Technical Field

[0001] This application relates to the field of wireless laser communication technology, and in particular to a beaconless optical tracking communication system, an optical capture alignment method, an electronic device, and a computer-readable storage medium. Background Technology

[0002] Laser communication technology boasts advantages such as small size, high security, and long-distance transmission, offering broad application prospects. It can be used for communication between fixed points, between mobile points, and between fixed and mobile points. A crucial prerequisite for the rapid, accurate, and stable transmission of information in laser communication systems under conditions of long distances, narrow beams, atmospheric turbulence, and terminal jitter interference is the need for rapid beam acquisition at the other end, ensuring optical signal alignment between the communicating parties and maintaining a stable communication link unaffected by various interferences. The development of APT (Acquisition, Pointing, and Tracking) systems has provided support for solving these problems.

[0003] APT systems can be structurally divided into two types: those with beacons and those without. Those with beacons refer to a system where the beacon light emitted by the optical communication terminal for locating the other terminal is different from the communication light; only the beacon light is used for tracking and aiming, which is currently the main application method. Those without beacons use the same beacon light as the communication light for tracking and aiming. Since beaconless APT systems do not require an additional beacon laser, they can reduce the weight and power consumption of the laser communication terminal compared to beacon-based APT systems. However, because the divergence angle of the communication light is smaller than that of the beacon light, it is more difficult to complete the scanning of uncertain areas and achieve reliable acquisition within a limited time.

[0004] Therefore, providing a laser communication system that is compact, lightweight, low-power, and capable of fast and accurate laser scanning, capture, and tracking is an urgent problem to be solved. Summary of the Invention

[0005] To overcome the shortcomings of the prior art, this invention provides a beaconless optical tracking communication system and application, which can solve the problems of large weight and power consumption of existing beacon-based APT systems and the difficulty of beaconless APT systems in quickly completing scanning and accurately capturing signals.

[0006] On one hand, the present invention provides a beaconless optical tracking communication system, comprising: an optical transmitter and an optical receiver; the optical transmitter includes: a laser and a transmitting antenna; the optical receiver includes: a receiving antenna, a fine alignment actuator, a beam splitter, a communication detector, and a spot detector; the laser beam emitted by the laser is transmitted by the transmitting antenna and received by the receiving antenna, and part of it enters the communication detector through the beam splitter to achieve communication function, and part of it enters the spot detector to achieve beam alignment and tracking function; the optical transmitter and / or the optical receiver are provided with a coarse alignment actuator to control the scanning trajectory of the laser beam so that a spot appears in the field of view of the spot detector; the fine alignment actuator controls the direction of the laser beam so that the spot reaches the target center position in the spot detector.

[0007] In one embodiment of the present invention, the coarse alignment actuator is mechanically connected to the transmitting antenna 3 and / or the receiving antenna, for controlling the pointing of the corresponding transmitting antenna and / or the receiving antenna, so that the executable range of the fine alignment actuator moves to a position containing the target bullseye.

[0008] In one embodiment of the present invention, the beaconless optical tracking communication system further includes: an optical fiber amplifier disposed between the laser and the transmitting antenna, wherein the laser beam emitted by the laser is output to the transmitting antenna by coupling into an optical fiber after passing through the optical fiber amplifier.

[0009] In one embodiment of the present invention, the light emitting end and the light receiving end are respectively provided with a control unit and a radio frequency communication module. The control unit is electrically connected to the coarse alignment actuator. The light receiving end and the light emitting end establish a communication connection through the radio frequency communication module, which is used to notify the control unit to control the coarse alignment actuator to stop scanning when the light spot appears in the field of view of the light spot detector.

[0010] In one embodiment of the present invention, the precision alignment actuator is a micro-mirror and is located only in the converging optical path of the light receiving end.

[0011] In one embodiment of the present invention, the spot detector is any one of a four-quadrant detector, a position-sensitive detector, a focal plane detector, a CCD, or a CMOS.

[0012] In one embodiment of the present invention, the coarse alignment actuator is a two-dimensional turntable, and the optical transmitter and the optical receiver share one coarse alignment actuator.

[0013] On the other hand, the present invention also proposes a light acquisition alignment method applicable to the beaconless optical tracking communication system described in any of the above embodiments, comprising: controlling a laser beam to perform one scanning cycle within a preset scanning range through a coarse alignment actuator; if the light spot detector at the light receiver fails to acquire the light spot within the scanning cycle, causing the field of view of the light spot detector to jump once, and re-performing one scanning cycle within the scanning range until the light spot is successfully acquired; driving the coarse alignment actuator to control the pointing of the transmitting antenna and / or the receiving antenna according to the position information of the acquired light spot, so that the executable range of the fine alignment actuator moves to a position containing the target center, thereby completing the coarse alignment; and driving the fine alignment actuator to control the pointing of the laser beam according to the position information of the light spot after coarse alignment, so that the light spot reaches the position of the target center in the light spot detector.

[0014] In another aspect, embodiments of the present invention also provide an electronic device, comprising: a memory and one or more processors connected to the memory, the memory storing a computer program, and the processors executing the computer program to implement the beaconless optical tracking communication method as described in any of the above embodiments.

[0015] Furthermore, this invention also proposes a computer-readable storage medium storing computer-executable instructions for performing the beaconless optical tracking communication method as described in any of the above embodiments.

[0016] As can be seen from the above, the embodiments of the present invention can have one or more of the following beneficial effects:

[0017] (1) The beaconless optical tracking communication system proposed in this invention utilizes signal light as both a communication beam and an alignment beam. The optical transmitter and receiver adopt a coaxial dual optical path to achieve the integration of tracking and communication optical paths, thereby reducing the size, weight and power consumption of the laser communication system. At the same time, the coarse alignment actuator controls the scanning trajectory of the laser beam to make a spot appear in the field of view of the spot detector. The fine alignment actuator controls the direction of the laser beam to make the spot reach the target center in the spot detector, thereby achieving rapid laser scanning and accurate spot capture and tracking.

[0018] (2) By using a spot detector set at the optical receiver to control the coarse alignment actuator and the fine alignment actuator in conjunction with the control unit, and by establishing a radio frequency communication module to establish a communication connection between the optical transmitter and the optical receiver, the system hardware structure is greatly simplified.

[0019] (3) The precision alignment actuator is located only in the converging optical path of the optical receiver, which simplifies the optical path and enables precise spot capture and tracking, thus effectively improving system performance. Attached Figure Description

[0020] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0021] Figure 1 This is a structural block diagram of a beaconless optical tracking communication system provided in an embodiment of the present invention;

[0022] Figure 2 This is a schematic diagram illustrating the coarse and fine alignment processes of a beaconless optical tracking communication system provided in an embodiment of the present invention. Detailed Implementation

[0023] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other. The present invention will now be described with reference to the accompanying drawings and embodiments.

[0024] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments, and should all fall within the protection scope of the present invention.

[0025] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this invention are applicable in distinguishing similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or applicable to such processes, methods, products, or apparatus.

[0026] It should also be noted that the division of multiple embodiments in this invention is only for the convenience of description and should not constitute a special limitation. Features in various embodiments can be combined and referenced in each other without contradiction.

[0027] like Figure 1As shown, the first embodiment of the present invention proposes a beaconless optical tracking communication system, which includes, for example, an optical transmitter and an optical receiver. The optical transmitter includes at least a laser 1 and a transmitting antenna 3; the optical receiver includes at least a receiving antenna 4, a precision alignment actuator 5, a beam splitter 6, a communication detector 7, and a spot detector 8.

[0028] The laser beam emitted by laser 1 is transmitted by transmitting antenna 3 and received by receiving antenna 4. It then enters communication detector 7 through beam splitting component 6 to realize communication function, and enters spot detector 8 to realize beam alignment and tracking function.

[0029] Specifically, laser 1 emits a laser beam with a main wavelength of 1550nm, which is then coupled into an optical fiber after passing through an EDFA fiber amplifier 2. To meet system miniaturization requirements, the output power is required to be no more than 2W. The 1550nm laser beam can also serve as both a signal beam and an alignment beam. After being emitted through transmitting antenna 3, the beam divergence angle is 0.1mrad-0.3mrad, and after passing through an atmospheric channel of 10km, it is received by receiving antenna 4.

[0030] Furthermore, the precision alignment actuator 5, for example, is a micro-mirror, located in the converging optical path of the optical receiver. The laser beam received by the receiving antenna 4 is reflected by the micro-mirror 5 into the beam splitter 6. The beam splitter 6 can be a beam splitting prism or any device with beam splitting characteristics. For example, 90% of the light in the laser beam passes through the beam splitter 6 and enters the communication detector 7 to achieve the communication function. The communication detector 7 can be an APD or a four-quadrant detector; here, for example, an APD with a photosensitive surface size of approximately 40 μm is selected. The remaining 10% of the light in the laser beam passes through the beam splitter 6 and enters the spot detector 8 to achieve the beam alignment and tracking function. The spot detector 8 can be any of a four-quadrant detector, a position-sensitive detector, a focal plane detector, a CCD, or a CMOS; here, for example, a focal plane detector with a diagonal field of view of approximately 6 mrad is selected. Both the APD and the focal plane detector are located at the focal point of the receiving optical path.

[0031] The optical transmitter and / or optical receiver are further equipped with a coarse alignment actuator 9, which is, for example, a two-dimensional turntable, used to control the scanning trajectory of the laser beam so that a light spot appears in the field of view of the spot detector 8. A fine alignment actuator 5 is used to control the direction of the laser beam so that the light spot reaches the target center position in the spot detector 8. In this way, it is possible to achieve integration of tracking and communication optical paths, reducing the size, weight, and power consumption of the laser communication system, while simultaneously achieving rapid laser scanning and precise spot capture and tracking.

[0032] Furthermore, the coarse alignment actuator 9 is mechanically connected to the transmitting antenna 3 and / or the receiving antenna 4 to control the pointing of the corresponding transmitting antenna 3 and / or receiving antenna 4, so that the executable range of the fine alignment actuator 5 is moved to a position containing the target center, that is, coarse alignment is achieved.

[0033] Furthermore, the light emitting end and the light receiving end are respectively provided with a control unit 10 and a radio frequency communication module 11. The control unit 10 is electrically connected to the coarse alignment actuator 9, and the light receiving end and the light emitting end establish a communication connection through the radio frequency communication module 11, which is used to notify the control unit 10 to control the coarse alignment actuator 9 to stop scanning when a light spot appears in the field of view of the light spot detector 8.

[0034] In this way, coarse alignment and fine alignment are achieved by sharing a single spot detector 8, which greatly simplifies the system hardware structure; and the fine alignment actuator 5 is located only in the converging optical path at the receiving end, which simplifies the optical path and improves system performance.

[0035] The following is combined with Figure 2 As shown, the optical signal acquisition and alignment process performed by the beaconless optical tracking communication system proposed in this invention will be described in detail:

[0036] The radio frequency communication module 11 of the transmitter and the optical receiver is, for example, a GSM / GPRS module, and the transmitter and the optical receiver are also equipped with a GPS positioning module.

[0037] The receiving end uses a GPS positioning module to measure the latitude, longitude, and altitude of its terminal location, and then sends the terminal location information to the other end via a GSM / GPRS module. At the same time, the transmitting end's GPS module also measures the location of its terminal, and processes the location information of both ends through a program to calculate the initial pointing azimuth and elevation angles. Finally, it drives the coarse alignment actuator 9 to adjust the beam direction and complete the initial pointing operation.

[0038] For example, a circular uncertain region is defined with the initial pointing position as the center and a radius of 3 times the standard deviation of elevation and azimuth. The field of view of the receiver's spot detector 8 is kept in a staring state. The transmitter controls the laser beam to execute a scanning trajectory to complete one scanning cycle through the coarse alignment actuator 9. If acquisition fails within this scanning cycle, the field of view of the spot detector 8 is skipped once, and the transmitter rescans the uncertain region until acquisition is successful.

[0039] When a light spot appears within the field of view of the receiver's spot detector 8, a text message containing a stop command is sent to the scanning end via the GSM / GPRS module. The receiver's spot detector 8 performs image processing on the acquired light spot and uses the processed light spot position information as feedback to drive the coarse alignment actuator 9 to control the antenna pointing, thereby performing coarse beam alignment. The main purpose of coarse alignment is to move the executable range of the fine alignment actuator 5 to the area including the target center, so that the fine alignment stage can be effectively executed.

[0040] After coarse alignment is completed, the target center is within the executable range of the fine alignment actuator 5. The receiver spot detector 8 performs image processing on the acquired spot, using the processed spot position information as feedback to drive the fine alignment actuator 5 to control the beam direction and perform fine beam alignment. Furthermore, for example, a tracking threshold can be set. When the offset between the spot centroid and the target center exceeds this threshold, the above steps are repeated to readjust the beam direction.

[0041] In summary, the beaconless optical tracking communication system proposed in this invention utilizes the signal light as both the communication beam and the alignment beam. A coaxial dual-optical path is used between the optical transmitter and receiver, integrating the tracking and communication optical paths. This reduces the size, weight, and power consumption of the laser communication system. Simultaneously, a coarse alignment actuator controls the scanning trajectory of the laser beam, causing a spot to appear in the field of view of the spot detector. A fine alignment actuator controls the direction of the laser beam, ensuring the spot reaches the target center in the spot detector. This achieves rapid laser scanning and precise spot capture and tracking. A spot detector located at the optical receiver, in conjunction with a control unit, controls both the coarse and fine alignment actuators. Furthermore, an RF communication module establishes a communication connection between the optical transmitter and receiver, significantly simplifying the system hardware structure. The fine alignment actuator is located only in the converging optical path at the optical receiver, simplifying the optical path while achieving precise spot capture and tracking, effectively improving system performance.

[0042] The second embodiment of the present invention proposes a light acquisition and alignment method, including steps S1 to S3. In step S1, a coarse alignment actuator controls a laser beam to perform one scanning cycle within a preset scanning range. If the light spot detector at the light receiver fails to acquire the light spot within the scanning cycle, the field of view of the light spot detector is skipped once, and another scanning cycle is performed within the scanning range until the light spot is successfully acquired. In step S2, based on the position information of the acquired light spot, the coarse alignment actuator controls the pointing of the transmitting antenna and / or the receiving antenna, moving the executable range of the fine alignment actuator to a position containing the target center, thus completing the coarse alignment. In step S3, based on the position information of the light spot after coarse alignment, the fine alignment actuator controls the pointing of the laser beam, causing the light spot to reach the position of the target center in the light spot detector.

[0043] It is worth mentioning that the optical capture alignment method proposed in the second embodiment of the present invention is applicable to the beaconless optical tracking communication system proposed in the first embodiment. The specific structure and function of the beaconless optical tracking communication system can be referred to the content described in the first embodiment, and will not be described in detail here. Moreover, the beneficial effects of the optical capture alignment method provided in this embodiment are the same as the beneficial effects of the beaconless optical tracking communication system provided in the first embodiment.

[0044] The third embodiment of the present invention also proposes an electronic device, for example including: at least one processing unit and at least one storage unit, wherein the storage unit stores a computer program, and when the computer program is executed by the processing unit, the processing unit performs the method described in the first embodiment, and the beneficial effects of the electronic device provided in this embodiment are the same as the beneficial effects of the light capture alignment method provided in the second embodiment.

[0045] The fourth embodiment of the present invention also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method, and the beneficial effects of the computer-readable storage medium provided in this embodiment are the same as the beneficial effects of the light capture alignment method provided in the second embodiment.

[0046] The computer-readable storage medium may include, but is not limited to, any type of disk, including floppy disks, optical disks, DVDs, CD-ROMs, microdrives, as well as magneto-optical disks, ROMs, RAMs, EPROMs, EEPROMs, DRAMs, VRAMs, flash memory devices, magnetic cards or optical cards, nanosystems (including molecular memory ICs), or any type of medium or device suitable for storing instructions and / or data.

[0047] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that this application is not limited to the described order of actions, as some steps may be performed in other orders or simultaneously according to this application. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions and modules involved are not necessarily essential to this application.

[0048] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0049] In the several embodiments provided in this application, it should be understood that the disclosed apparatus can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some service interface; the indirect coupling or communication connection between devices or units may be electrical or other forms.

[0050] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0051] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0052] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage device (CMD). Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a memory and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned memory includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0053] Those skilled in the art will understand that all or part of the steps in the various methods of the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, which may include: a flash drive, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, etc.

[0054] The foregoing description is merely an exemplary embodiment of this disclosure and should not be construed as limiting the scope of this disclosure. Any equivalent changes and modifications made in accordance with the teachings of this disclosure shall still fall within the scope of this disclosure. Those skilled in the art will readily conceive of embodiments of this disclosure upon considering the specification and practicing the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not described herein. The specification and embodiments are to be considered exemplary only, and the scope and spirit of this disclosure are defined by the claims.

[0055] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0056] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A beaconless optical tracking communication system, characterized in that, include: Optical transmitter and optical receiver; The light emitting end includes: a laser (1) and a transmitting antenna (3); the light receiving end includes: a receiving antenna (4), a precision alignment actuator (5), a beam splitter (6), a communication detector (7), and a spot detector (8); the precision alignment actuator (5) is a micro-mirror and is located only in the converging optical path of the light receiving end; The laser beam emitted by the laser (1) is received by the receiving antenna (4) after being emitted by the transmitting antenna (3), and enters the communication detector (7) through the beam splitter (6) to realize the communication function, and enters the spot detector (8) to realize the beam alignment and tracking function. The light emitting end and / or the light receiving end are provided with a coarse alignment actuator (9) for controlling the scanning trajectory of the laser beam so that a light spot appears in the field of view of the light spot detector (8); The light transmitter and the light receiver are respectively provided with a control unit (10) and a radio frequency communication module (11). The control unit (10) is electrically connected to the coarse alignment actuator (9). The light receiver and the light transmitter establish a communication connection through the radio frequency communication module (11) to notify the control unit (10) to control the coarse alignment actuator (9) to stop scanning when the light spot appears in the field of view of the light spot detector (8). The precision alignment actuator (5) controls the direction of the laser beam so that the light spot reaches the target center in the light spot detector (8).

2. The beaconless optical tracking communication system according to claim 1, characterized in that, The coarse alignment actuator (9) is mechanically connected to the transmitting antenna (3) and / or the receiving antenna (4) to control the pointing of the corresponding transmitting antenna (3) and / or the receiving antenna (4), so that the executable range of the fine alignment actuator (5) moves to a position containing the target bullseye.

3. The beaconless optical tracking communication system according to claim 1, characterized in that, Also includes: An optical fiber amplifier (2) is disposed between the laser (1) and the transmitting antenna (3). The laser beam emitted by the laser (1) is output to the transmitting antenna (3) after being coupled into the optical fiber through the optical fiber amplifier (2).

4. The beaconless optical tracking communication system according to claim 1, characterized in that, The spot detector (8) is any one of a four-quadrant detector, a position-sensitive detector, a focal plane detector, a CCD, or a CMOS.

5. The beaconless optical tracking communication system according to claim 1, characterized in that, The coarse alignment actuator (9) is a two-dimensional turntable, and the optical transmitter and the optical receiver share one coarse alignment actuator (9).

6. A method for aligning light capture, characterized in that, The beaconless optical tracking communication system according to any one of claims 1-5 includes: The coarse alignment actuator controls the laser beam to perform one scanning cycle within a preset scanning range. If the spot detector at the light receiver fails to capture the spot within the scanning cycle, the field of view of the spot detector is skipped once, and another scanning cycle is performed within the scanning range until the spot is successfully captured. Based on the position information of the captured light spot, the coarse alignment actuator is driven to control the pointing of the transmitting antenna and / or the receiving antenna, so that the executable range of the fine alignment actuator moves to a position containing the target center, thus completing the coarse alignment; Based on the position information of the light spot after coarse alignment, the fine alignment actuator is driven to control the direction of the laser beam, so that the light spot reaches the position of the target center in the light spot detector.

7. An electronic device, characterized in that, include: A memory and one or more processors connected to the memory, the memory storing a computer program, the processors being configured to execute the computer program to implement the steps of the method as claimed in claim 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions for performing the steps of the method as described in claim 6.

Images