Integrated GNSS INS Navigation Coherent Integration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional ultra-tightly coupled GNSS and INS systems require high-rate Kalman Filters, which demand high computer throughput and are vulnerable to jamming, limiting their anti-jamming capability and efficiency.
Innovation Solution
The system integrates I and Q signals of GNSS and INS signals at a low rate (0.1 Hz to 1.0 Hz), allowing coherent integration and reducing the computational burden on the Kalman Filter, thereby enhancing anti-jamming capability and reducing throughput demands.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional ultra-tightly coupled GNSS and INS systems operate at high rate (50 Hz), then navigation accuracy and tracking performance are improved, but computer throughput demand increases and anti-jamming capability deteriorates
Solution Approach 1:
The system segments the signal processing into two distinct stages: (1) coherent integration of GNSS signals at high rate to extract correlation data, and (2) Kalman Filter processing at reduced rate (0.1-1.0 Hz) using the integrated results. This segmentation allows the computationally intensive signal integration to occur at high rate while the navigation solution computation occurs at lower rate, resolving the throughput demand issue while maintaining accuracy.
Solution Approach 2:
The patent introduces an intermediate coherent integration stage that processes GNSS signals at high rate and produces condensed navigation data for the Kalman Filter. This intermediary processing stage acts as a bridge between high-rate signal acquisition and low-rate navigation solution computation, reducing the computational burden on the Kalman Filter while preserving navigation accuracy.
2Reliability
If conventional systems use high-rate Kalman Filter (50 Hz), then tracking performance is improved, but vulnerability to jamming increases
Solution Approach 1:
By segmenting the processing rates - performing coherent integration at high rate for accurate tracking while running Kalman Filter at low rate (0.1-1.0 Hz) - the system achieves robust tracking performance through the integrated correlation data while reducing the window of vulnerability to jamming attacks on the navigation solution computation.
Solution Approach 2:
The system employs periodic coherent integration of GNSS signals at the predetermined low rate (0.1-1.0 Hz) to update the Kalman Filter. This periodic updating maintains reliable tracking through accumulated signal energy while reducing exposure to continuous jamming, as the filter updates occur at intervals rather than continuously at high rate.
3Productivity
If the Kalman Filter operates at low rate (0.1 Hz to 1.0 Hz), then computer throughput demand is reduced, but navigation update frequency decreases
Solution Approach 1:
The system performs preliminary coherent integration of GNSS signals at high rate before passing results to the low-rate Kalman Filter. This preliminary processing accumulates sufficient navigation data in advance, allowing the Kalman Filter to operate at low rate (0.1-1.0 Hz) while still producing accurate and timely navigation solutions without excessive throughput demand.
Data Source
AI summary
A system for navigation and tracking may include an inertial navigation system adapted to generate a replica GNSS signal and a global navigation satellite system. The global navigation satellite system may include a module to digitize a GNSS signal received from a constellation of global navigation satellites. A correlator receives the digitized GNSS signal and the replica GNSS signal. The correlator correlates the digitized GNSS signal to the replica GNSS signal to generate a correlated GNSS signal. A coherent integration module coherently integrates the correlated GNSS signal to generate an integrated signal having a predetermined rate. A filter receives the integrated signal and generates a data signal for navigation and tracking. An output device may present the navigation and tracking information based on the data signal, or the navigation and tracking information may be used to provide guidance for a vehicle or may be used to track a target.