Wide-Band Interference Mitigation in GNSS Receivers Using Sub-Band Automatic Gain Control.

Area of Science:

• Signal Processing
• Navigation Systems
• Electromagnetics

Background:

• Global Navigation Satellite System (GNSS) receiver performance is degraded by interference signals.
• Existing interference mitigation (IM) methods like the high-rate DFT-based data manipulator (HDDM) pulse blanker (PB) struggle with wide-band noise signals.
• Previous analyses focused on carrier-to-noise density ratio (C/N0), neglecting the impact on the overall navigation solution.

Purpose of the Study:

• To introduce and evaluate the HDDM-AGC algorithm for GNSS interference mitigation.
• To assess the impact of HDDM-AGC on the position, velocity, and time (PVT) solution, enabling end-to-end evaluation.
• To compare the performance of HDDM-AGC against existing methods on both high-end and low-cost GNSS receivers.

Main Methods:

• Integration of automatic gain control (AGC) into the HDDM structure to create HDDM-AGC.
• Analysis of HDDM-AGC's effect on GNSS receiver PVT solution performance.
• Experimental comparison of two commercial receivers (high-end and low-cost) with and without HDDM-AGC against laboratory-generated interference signals.

Main Results:

• HDDM-AGC provides PVT availability and precision comparable to high-end receivers for most interference types, outperforming them for pulsed interference.
• The algorithm minimizes performance degradation against wide-band noise signals.
• For low-cost receivers, HDDM-AGC application increased PVT availability by up to 40%.

Conclusions:

• HDDM-AGC effectively mitigates a wider range of interference signals compared to traditional HDDM.
• The algorithm offers a cost-effective solution for enhancing GNSS receiver performance, particularly for low-cost devices.
• This study provides a comprehensive evaluation of IM techniques on GNSS PVT solutions.