Sample-Wise Aiding in GPS/INS Ultra-Tight Integration for High-Dynamic, High-Precision Tracking

Area of Science:

• Navigation Systems Engineering
• Signal Processing
• Aerospace Engineering

Background:

• Ultra-tightly coupled Global Positioning System (GPS) and Inertial Navigation System (INS) enhance navigation performance in challenging environments.
• Traditional INS aiding methods, limited by discrete data injection, restrict the accommodation of high dynamics.

Purpose of the Study:

• To present a novel sample-wise aiding method for GPS/INS ultra-tight coupling.
• To enhance the dynamic error suppression capabilities of GPS receivers.

Main Methods:

• Developed a sample-wise aiding technique that interpolates aiding Doppler into each digital signal sample.
• Derived analytical relationships between tracking error and aiding rate.
• Simulated and compared linear and spline interpolation methods against traditional aiding.

Main Results:

• Sample-wise aiding significantly reduces dynamic stress errors compared to traditional methods.
• The method's effectiveness was validated through simulations and tests using a digital intermediate frequency (IF) signal simulator and software receiver.
• Theoretical equations were confirmed by experimental results.

Conclusions:

• Sample-wise aiding is a superior method for improving GPS/INS navigation accuracy under high dynamic conditions.
• The proposed technique effectively mitigates dynamic errors, enhancing overall system robustness.