Satellite Antenna Speed Control for Jitter Reduction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Satellite antennas in low earth orbit face challenges in maintaining stable communication due to rapid movement and jitter issues, which degrade image quality, as they need to orient accurately towards a ground station within a limited beam width, often exceeding dynamic limits and causing resonance-induced vibrations.
Innovation Solution
An apparatus and method that calculate and control the driving speed of the antenna using a calculator to determine azimuth and elevation position ranges for an effective beam width, generating a shortest path profile to minimize speed and prevent jitter, employing a biaxial gimbal-type structure and optimizing velocity and acceleration thresholds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the antenna is oriented accurately to a ground station within a limited beam width, then communication reliability is improved, but the driving speed exceeds dynamic limits causing jitter and vibration
Solution Approach 1:
The patent applies dynamics by making the antenna driving speed variable rather than constant. The controller dynamically adjusts the driving speed based on the satellite's orbital position and the calculated effective beam width coverage range, allowing the antenna to move faster when the beam width covers the ground station and slower when approaching orientation limits, thus resolving the contradiction between maintaining communication reliability and exceeding dynamic speed limits
Solution Approach 2:
The patent changes the parameter of driving speed from a fixed value to a variable parameter that is continuously adjusted based on orbital position and beam width characteristics. By calculating the effective beam width coverage range and comparing it with the ground station position, the system optimizes the driving speed parameter to prevent jitter while maintaining communication reliability
2Stability of the object's composition
If the antenna driving speed is increased to maintain orientation accuracy, then communication stability is improved, but resonance-induced vibrations and jitter occur
Solution Approach 1:
The patent implements feedback by continuously monitoring the satellite's orbital position and the antenna's orientation status, then adjusting the driving speed accordingly. The controller receives feedback about the beam width coverage range and ground station position, and modifies the driving commands to maintain orientation stability within the effective beam width while avoiding speed-induced jitter and vibration
Solution Approach 2:
The patent applies beforehand cushioning by calculating in advance the effective beam width coverage range and identifying critical orientation points where speed reduction is necessary. The controller pre-adjusts the driving speed before the antenna reaches orientation limits or regions prone to jitter, preventing resonance-induced vibrations before they occur
Data Source
AI summary
Provided is an apparatus for controlling a driving speed of an antenna of a mobile satellite travelling in an orbit. The apparatus may include a calculator configured to calculate an azimuth position range and an elevation position range for an effective beam width of the antenna based on an antenna orientation at which the antenna of the mobile satellite is oriented correctly to a ground station from a point in the orbit, and a controller configured to control a speed of the antenna based on a first azimuth in the azimuth position range and a first elevation in the elevation position range.