CN-121984573-A - Method for generating satellite communication beam

CN121984573ACN 121984573 ACN121984573 ACN 121984573ACN-121984573-A

Abstract

The invention discloses a method for generating satellite communication beams, which comprises the steps of obtaining boundary coordinates of a target geographic corridor and converting the boundary coordinates into satellite angular domain representation, extracting skeleton curves of the corridor based on the angular domain boundaries, establishing a parameterized beam pattern model distributed along the skeleton curves, constructing a beam forming weight optimization problem which comprises coverage gain constraints distributed along the skeleton curves and continuity constraints between adjacent sampling positions on the skeleton curves, solving the optimization problem to obtain complex weight vectors, and loading the complex weight vectors to a beam forming network to drive a phased array antenna. According to the invention, the two-dimensional area coverage problem is reduced in dimension through skeleton curve modeling, and the energy smooth transition of the beam along the curved corridor is ensured by utilizing the continuity constraint explicit, so that the problems of difficult optimization convergence and discontinuous coverage in the long and narrow non-convex area coverage are effectively solved.

Inventors

ZHAO FEI
WU LIANG
ZHENG CHENGHUI
WAN KUN

Assignees

南京控维通信科技有限公司

Dates

Publication Date: 20260505
Application Date: 20260401

Claims (10)

1. A method for generating a satellite communication beam, comprising: Obtaining boundary coordinates of a target geographic corridor and converting the boundary coordinates into angular domain representations under a satellite coordinate system; Based on the angular domain representation, extracting a skeleton curve of a target geographic corridor, and establishing a parameterized beam pattern model distributed along the skeleton curve; constructing a beam forming weight optimization problem based on the parameterized beam pattern model, wherein the beam forming weight optimization problem comprises coverage gain constraints distributed along a skeleton curve and continuity constraints between adjacent sampling positions on the skeleton curve; solving a beam forming weight optimization problem to obtain a beam forming complex weight vector; Loading the beam forming complex weight vector into a pre-configured beam forming network, and driving the phased array antenna to radiate a communication beam matched with the shape of the target geographic corridor.
2. The method according to claim 1, wherein establishing a parameterized beam pattern model distributed along a skeleton curve comprises constructing a corridor width function, in particular: based on the angular domain representation, extracting a left boundary point set and a right boundary point set of a target geographic corridor, and calculating a midpoint sequence of a corresponding boundary point; fitting the midpoint sequence to obtain a continuous parameterized representation c (t) of the skeleton curve, wherein t is a normalized arc length parameter along the corridor direction; Based on the continuous parameterized representation, the angular distance between the left boundary point set and the right boundary point set under the satellite view angle is calculated, and a corridor width function distributed along the skeleton curve is constructed.
3. The method according to claim 2, wherein establishing a parameterized beam pattern model distributed along a skeleton curve, further comprises generating a set of coverage slice points, in particular: Calculating tangential vectors and normal vectors at sampling positions of the skeleton curve, and establishing a local coordinate system, wherein the tangential vectors are along the extending direction of the skeleton curve, and the normal vectors are perpendicular to the tangential vectors; Based on the local coordinate system, sampling is performed in the direction of the normal vector and within a range determined by the corridor width function, and a coverage slice point set corresponding to the sampling position is generated.
4. The method according to claim 2, wherein constructing the beamforming weight optimization problem comprises dividing the target geographic corridor into predetermined subsections, in particular: calculating curvature distribution of the skeleton curve along the parameter t; Based on curvature distribution, dividing the target geographic corridor into preset subsections along a skeleton curve, wherein curvature integral values in each subsection are smaller than a preset curvature threshold value, and enabling local areas corresponding to the subsections to show convex geometric characteristics.
5. The method of claim 4, wherein in each sub-segment, the coverage gain constraint is specifically configured as a field strength domain convexity constraint; After the reference phase corresponding to the subsection is introduced, the real part of the product of the beam forming complex weight vector and the guide vector of the sampling point in the subsection after the phase rotation is not lower than the preset field strength threshold corresponding to the gain threshold.
6. The method of claim 5, wherein the continuity constraint is specifically configured as an inter-segment field strength continuity coupling constraint; The continuous coupling constraint of field intensity between segments requires that at the junction of two adjacent subsections, the difference between the complex field intensity corresponding to the tail end of the former subsection and the complex field intensity corresponding to the beginning of the latter subsection, or the difference between the complex field intensity and the preset boundary reference field intensity, does not exceed the preset coupling tolerance.
7. The method of claim 6, wherein solving a beamforming weight optimization problem comprises: constructing an augmented Lagrangian function, wherein the augmented Lagrangian function comprises a preconfigured original optimization target and intersegmental field strength continuity coupling constraint serving as a penalty term; Carrying out iterative solution on the extended Lagrangian function by adopting an alternate direction multiplier method, wherein each iteration of iterative solution comprises a weight updating step, a reference field intensity updating step and a multiplier updating step which are alternately executed; the weight updating step is to solve a beam forming complex weight vector which minimizes an augmented Lagrangian function in a feasible domain which meets the field strength domain salinization constraint under the condition of fixed boundary reference field strength and Lagrangian multipliers.
8. The method according to claim 7, wherein the process of iterative solution further comprises a phase adaptive update step, in particular: calculating an array response phase corresponding to the center position of the sub-segment by using the beam forming complex weight vector updated by the current round; Updating the array response phase to be the reference phase used by the subsection in the next round, and correcting the definition of the field intensity domain saliency constraint according to the reference phase so as to reduce the approximation error between the field intensity domain saliency constraint and the preset original power gain constraint.
9. The method of claim 1, wherein the continuity constraint is further configurable to: calculating the absolute value of the difference between the beam gain corresponding to the former sampling position and the beam gain corresponding to the latter sampling position at any two adjacent sampling positions of the skeleton curve; the absolute value of the difference is required not to exceed a preset margin of the along-path gain fluctuation.
10. The method of claim 9, wherein solving a beamforming weight optimization problem comprises: Introducing a semi-positive matrix variable to replace the beamforming complex weight vector, and converting the non-convex quadratic constraint on the beamforming complex weight vector into a linear constraint on the semi-positive matrix variable; Neglecting rank-one constraint of the semi-positive definite matrix variable, relaxing a beam forming weight optimization problem into a semi-positive definite programming problem, and solving to obtain an optimal semi-positive definite matrix; And if the rank of the optimal semi-positive definite matrix is greater than one, recovering the beam forming complex weight vector meeting the coverage gain constraint and the continuity constraint from the optimal semi-positive definite matrix by using a Gaussian randomization method.

Description

Method for generating satellite communication beam Technical Field The invention belongs to the field of satellite communication, and particularly relates to a method for generating a satellite communication beam. Background In a satellite communication system, the multi-beam phased array antenna can flexibly change the beam direction and shape by controlling the amplitude and the phase of a radiation unit, so as to realize the accurate coverage of a specific geographic area. For a strip geographic area (such as a serpentine river, a coastline or a traffic trunk line) with large span and irregular shape, generating a formed wave beam which is highly matched with a geographic contour has important technical significance for improving the utilization rate of satellite transmitting power, enhancing the signal strength of an edge area and improving the use efficiency of spectrum resources. At present, an optimization method based on two-dimensional grid sampling is generally adopted for the beam forming technology of an irregular area. The method comprises the steps of discretizing a target coverage area into a dense two-dimensional longitude and latitude grid point set, taking the gain requirement of each grid point as an independent constraint condition, and solving antenna weight vectors by utilizing semi-positive relaxation (SDR) or a heuristic algorithm (such as a genetic algorithm) so as to meet gain thresholds of all grid points and inhibit side lobes. The method is widely applied when processing the bulk region (such as province or country outline) with regular shape and good convexity. However, for horseshoe-shaped or long and narrow bent strip-shaped areas, the existing two-dimensional sampling method has a technical bottleneck that the dimension-constrained disaster and the coverage continuity are difficult to be compatible. In particular, to approach the boundary of the elongated bend, the two-dimensional grid method requires extremely high density of sampling points, resulting in an exponential increase in the number of constraints of the optimization problem, a computational complexity that is too high and tends to be prone to local optimizations. In addition, because the power gain constraint is non-convex in nature, and the traditional method lacks utilization of geometric topological characteristics of the region, when a highly non-convex bending part is processed, the constraint among discrete points lacks internal association, the algorithm is difficult to automatically ensure smooth transition of beam energy along the trend of a corridor, gain collapse or coverage fracture is easy to generate at the bending part, and continuous communication requirements of a high-speed mobile terminal are difficult to meet. Disclosure of Invention The object of the present invention is to provide a method for generating a satellite communication beam, which solves the above-mentioned problems of the prior art. Technical solution, a method for generating a satellite communication beam, includes: Obtaining boundary coordinates of a target geographic corridor and converting the boundary coordinates into angular domain representations under a satellite coordinate system; Based on the angular domain representation, extracting a skeleton curve of a target geographic corridor, and establishing a parameterized beam pattern model distributed along the skeleton curve; constructing a beam forming weight optimization problem based on the parameterized beam pattern model, wherein the beam forming weight optimization problem comprises coverage gain constraints distributed along a skeleton curve and continuity constraints between adjacent sampling positions on the skeleton curve; solving a beam forming weight optimization problem to obtain a beam forming complex weight vector; Loading the beam forming complex weight vector into a pre-configured beam forming network, and driving the phased array antenna to radiate a communication beam matched with the shape of the target geographic corridor. The method has the beneficial effects that the two-dimensional area coverage problem is reduced in dimension through skeleton curve modeling, and the energy smooth transition of the beam along the curved corridor is ensured by utilizing the continuity constraint explicit mode, so that the problems of difficult optimization convergence and discontinuous coverage in the long and narrow non-convex area coverage are effectively solved. Drawings Fig. 1 is a flowchart of steps in a method for generating a satellite communication beam according to an embodiment of the present application. Fig. 2 is a flowchart illustrating steps for constructing a corridor width function according to an embodiment of the present application. Fig. 3 is a flowchart of a step of generating a coverage slice point set according to an embodiment of the present application. Fig. 4 is a flowchart illustrating steps for dividing a target geographic corridor into prede