CN-122001477-A - One-to-many laser communication tracking method

CN122001477ACN 122001477 ACN122001477 ACN 122001477ACN-122001477-A

Abstract

The invention discloses a one-to-many laser communication tracking method, which adopts an optical transmitting array unit to generate multipath coherent optical signals, realizes independent modulation, phase regulation and dynamic route reconstruction of the optical signals through a beam splitting modulation module, a two-stage phase programmable optical fiber delay line and a reconfigurable optical route exchange matrix, utilizes a MEMS array and an optical phased array antenna to realize a composite scanning mechanism combining large-angle coarse pointing and small-range high-precision electronic scanning in a cooperative manner to complete independent tracking and laser transmitting of multiple targets, realizes integrated signal receiving and processing through a communication receiving unit, and forms a self-adaptive closed-loop control system based on a random parallel gradient descent algorithm by a core control module to optimize beam quality and tracking stability in real time. The invention has the advantages of compact structure, wide view field, high precision, strong self-adaption and the like, and is suitable for a low-orbit satellite laser communication network.

Inventors

GAN JIAWEI
HOU XIA
FANG FAN
WAN YUAN
ZHOU LIBING
CHEN XIAO
LU SHAOWEN
HUANG YINGXIA
WU LEI

Assignees

中国科学院上海光学精密机械研究所

Dates

Publication Date: 20260508
Application Date: 20260109

Claims (9)

1. A one-to-many laser communication tracking method is characterized by comprising the following steps: S1, generating a plurality of paths of coherent optical signals capable of being modulated and phase regulated independently, namely generating coherent laser signals by using a laser seed light source (1), and forming a plurality of paths of parallel optical signals which carry information and can be regulated and controlled independently in phase through a beam splitting modulation module consisting of a tree beam splitting network primary module (2), an electro-optical modulator (3) and a1 XN beam splitter (4); S2, multistage phase regulation and dynamic light path reconstruction, namely firstly carrying out phase coarse adjustment on the multi-path light signals generated by S1 through a first-stage phase programmable optical fiber delay line (5), then inputting the multi-path light signals into a reconfigurable light path switching matrix (6) to carry out dynamic coupling and routing distribution of the light signals, and then carrying out phase fine adjustment on the reconstructed light signals through a second-stage phase programmable optical fiber delay line (5) to form emission light beams with preset wave front characteristics and directivity; S3, combining scanning and multi-target pointing, namely guiding the generated emission light beam to an MEMS array through a light splitting matrix (7), utilizing the MEMS array to realize large-angle rapid mechanical deflection so as to finish rough pointing, and then performing small-range high-precision electronic scanning and beam forming on the basis of mechanical rough pointing through an optical phased array antenna which works cooperatively with the MEMS array so as to realize independent tracking and laser emission of a plurality of communication targets; S4, self-adaptive closed-loop control, namely, based on real-time monitoring of the working state of a system and performance feedback of a receiving end detector (9), calculating and outputting control signals in real time by adopting a random parallel gradient descent algorithm, and dynamically adjusting working parameters of the phase programmable optical fiber delay line (5), the reconfigurable optical routing exchange matrix (6) and the MEMS array to form closed-loop control so as to maintain beam quality and tracking stability; S5, integrated receiving and signal recovering, wherein in a receiving link, an incident light beam from free space is led in through the light splitting matrix (7), and sequentially subjected to receiving phase compensation through the phase programmable optical fiber delay line (5), receiving light path selection through the reconfigurable light path switching matrix (6) and focusing through the lens (8), and photoelectric conversion and signal processing are completed through the detector (9) and the receiver (10) to recover communication information; The reconfigurable optical routing switching matrix (6), the phase programmable optical fiber delay line (5) and the light splitting matrix (7) are multiplexed in a transmitting link and a receiving link to form a transceiver integrated optical architecture.
2. The one-to-many laser communication tracking method according to claim 1, wherein in S1, the electro-optical modulator (3) is a mach-zehnder modulator.
3. The one-to-many laser communication tracking method according to claim 1, characterized in that in S1, the N value of the 1 xn beam splitter (4) is at least 16, and the reconfigurable optical routing switching matrix (6) supports dynamic routing of multiple optical signals to not less than 64 optical channels.
4. The one-to-many laser communication tracking method according to claim 1, wherein in S2, the first-stage and second-stage phase programmable optical fiber delay lines (5) are respectively used for realizing large-range phase pre-correction before beam synthesis and high-precision phase compensation after synthesis.
5. The one-to-many laser communication tracking method according to claim 1, wherein in S3, the MEMS array is a biaxial torsion beam type piezoelectric ceramic driving array.
6. The one-to-many laser communication tracking method according to claim 1, wherein in S3, the optical phased array antenna realizes independent control of the outgoing optical phase of each radiation unit based on the fine phase control signal output by the second-stage phase programmable optical fiber delay line (5).
7. The one-to-many laser communication tracking method according to claim 1, wherein in S4, the random parallel gradient descent algorithm performs gradient estimation and optimization with the optical power or communication signal-to-noise ratio received by the detector (9) as a performance evaluation function.
8. The one-to-many laser communication tracking method according to claim 1, wherein the step S4 further comprises monitoring the output parameter of the laser seed light source (1) in real time through a phase programmable optical fiber delay line feedback control system, and dynamically adjusting the driving condition thereof to maintain the working stability of the light source.
9. The one-to-many laser communication tracking method according to claim 1, wherein in S5, the phase programmable optical fiber delay line (5) is used in a receiving link to compensate for a receiving phase error caused by an optical path difference or an environmental disturbance.

Description

One-to-many laser communication tracking method Technical Field The invention relates to the technical field of laser communication and optical tracking, in particular to a one-to-many laser communication tracking method which is suitable for inter-satellite and satellite-ground laser communication in a low earth orbit satellite internet system. In response to the trend of future weight reduction and miniaturization, the laser communication terminal has wider field of view and more functionality on the premise of reducing the number and the size of the laser communication terminals. Background With the rapid development of the low earth orbit satellite Internet, laser communication becomes an important technical direction of inter-satellite and satellite-ground communication due to the advantages of high bandwidth, high safety, electromagnetic interference resistance and the like. In satellite networking, the one-to-many laser communication mode has important application value, and can realize high-efficiency data transmission between a single satellite and a plurality of satellites or ground stations. However, conventional implementations typically mount multiple independent laser communication terminals on a single satellite, each terminal being responsible for one direction of communication. Although the scheme has definite functions, the scheme also has obvious limitation that a plurality of terminals cause the increase of the load weight, the increase of the power consumption, the complex structure and the great increase of the cost of the satellite platform, and the miniaturization and the low-cost development of the satellite are seriously restricted. At present, researches on one-to-many laser communication are focused on an optical phased array technology, and the beam direction is adjusted in an electric control mode, so that multi-target tracking and communication without mechanical rotation are realized. However, the existing tracking method based on the optical phased array still has a plurality of defects that the scanning angle is limited by the size and arrangement mode of antenna units, the field of view is generally narrow, the quality of light beams is easily affected by phase errors, the communication performance is reduced, the number of system units is limited, the expansibility is insufficient, the phase control precision is low, and high-precision pointing and stable tracking are difficult to realize. These problems limit the applicability and reliability of this approach in a dynamic, multi-target satellite communication environment. Therefore, a novel one-to-many laser communication tracking method is needed, which can realize a system design with wide field of view, high precision, light weight and low cost on the premise of ensuring communication quality so as to meet the requirements of a large-scale satellite constellation in the future on high-efficiency, flexible and sustainable communication capability. Disclosure of Invention In order to overcome the problems that the existing laser communication tracking and aiming requires a large amount of satellite platform resources and is large in size and the requirement of satellite internet users on large-capacity data transmission is increased, the invention provides a one-to-many laser communication tracking and aiming method, which can realize a wider scanning angle, more accurate phase control precision and more portable and miniaturized structural design, has the characteristics of simple structure, light weight, low platform resource occupancy rate, large view field and high precision, solves the problem that the traditional laser communication occupies large resources, and also solves the problems that the existing one-to-many laser communication tracking and aiming has small scanning angle and low phase control precision. The technical scheme of the invention is as follows: a one-to-many laser communication tracking method is characterized by comprising the following steps: s1, generating a plurality of paths of coherent optical signals capable of being modulated and phase regulated independently, namely generating coherent laser signals by using a laser seed light source, and forming a plurality of paths of parallel optical signals which carry information and can be regulated and controlled independently in phase by a beam splitting modulation module consisting of a tree beam splitting network primary module, an electro-optical modulator and a 1 XN beam splitter; S2, multistage phase regulation and dynamic light path reconstruction, namely carrying out phase coarse adjustment on the multi-path light signals generated in the step S1 through a first-stage phase programmable optical fiber delay line, then inputting the multi-path light signals into a reconfigurable light path routing exchange matrix to carry out dynamic coupling and routing distribution of the light signals, and carrying out phase fine adjustment on the recon