Satellite Terminal Geolocation via Doppler Compensation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current geolocation methods for identifying and locating VSAT TDMA terminals causing uplink cross-polarization and adjacent satellite interference are inaccurate due to low signal-to-noise ratios and interference from other communication signals.
Innovation Solution
A system comprising a signal ground receiver, signal processing device, and geolocation module that receives and analyzes signals of opposite polarities to detect and geolocate interfering terminals, applying Doppler compensation and cross-ambiguity functions to improve accuracy and handle low signal-to-noise ratios.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If geolocation methods using frequency difference of arrival (FDOA) or time difference of arrival (TDOA) are implemented, then terminal location can be determined, but measurement precision deteriorates due to low signal-to-noise ratio
Solution Approach 1:
The system performs preliminary actions by retrieving and storing bursts for signals of opposite polarities before interference detection occurs. The monitoring device accumulates signal data over time, building a database of reference bursts that can be correlated with interference signals later, enabling accurate geolocation even when the actual interference signal has low signal-to-noise ratio.
Solution Approach 2:
The system uses correlation between retrieved bursts and received signals to detect interference sources. By comparing the phase and frequency characteristics of bursts from opposite polarities, the system generates feedback information about potential interference sources, which is then used to refine the geolocation calculation and improve measurement precision.
2Reliability
If signal monitoring is performed to detect interfering terminals, then interference sources can be identified, but acquisition time increases due to the need for high signal-to-noise ratio
Solution Approach 1:
The monitoring device retrieves bursts for signals of opposite polarities in advance, before interference detection is needed. This preliminary data collection allows the system to have reference signals ready for immediate correlation when interference occurs, significantly reducing the acquisition time required to detect and locate interfering terminals while maintaining reliable detection accuracy.
3Productivity
If multiple spot beams with same frequency band are used to enhance throughput, then data transmission capacity increases, but polarity interference and adjacent satellite interference increase
Solution Approach 1:
The monitoring device continuously monitors signals from multiple spot beams and uses correlation techniques to detect polarity interference and adjacent satellite interference. By comparing signals of opposite polarities and analyzing their phase relationships, the system generates feedback about interference levels, enabling operators to identify and mitigate interference sources while maintaining high throughput from multiple spot beams.
Solution Approach 2:
The system uses signal correlation as an intermediary mechanism to distinguish between desired signals and interference. By correlating bursts from opposite polarities and analyzing the results, the system can identify interference sources without disrupting the normal operation of multiple spot beams, allowing throughput enhancement to continue while interference is managed.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively geolocates interfering terminals with high acquisition times, improving accuracy without degrading signal-to-noise ratios, enabling precise identification and correction of interference sources.
Implementation Method 1
said geolocation module being configured to apply Doppler compensation to the signal having first polarity from satellite in order to compensate said satellite movement
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The invention relates to a system comprising at least a geolocation module (10) configured to receive data from a processing device to geolocate terminals (11) causing polarity interference, said geolocation module (10) being configured to apply Doppler compensation to a signal having first polarity (16') from a satellite (S1) in order to compensate said satellite movement.