Analysis of Chirp Interference Effects on GPS L1 C/A Software Receiver Acquisition
Year: 2026
Type: conference-paper
Abstract: Global Navigation Satellite System (GNSS) receivers are susceptible to radio-frequency interference owing to the low received power of GNSS signals. Chirp interference is particularly relevant to GPS L1 C/A acquisition because its time-varying frequency can distort the code phase–Doppler search surface. This paper examines the acquisition-stage response of a GPS L1 C/A software receiver to continuous linear chirp interference using real intermediate-frequency (IF) data. Chirp signals with controlled sweep bandwidths, sweep periods, and power levels are injected into baseline IF samples, and the response is characterized by the peak metric and normalized code phase–Doppler search surface. For the tested IF data and acquisition setup, degradation varies non-monotonically with sweep bandwidth: medium-bandwidth chirps produce stronger off-peak responses and secondary peaks than narrowband and MHz-level wideband cases, reducing the relative dominance of the main correlation peak. The sweep-period results indicate that degradation is associated with recurrence of chirp-induced structures across coherent integration blocks and frequency coverage within each 1 ms coherent block. These findings provide an acquisition-stage reference for parameter-aware interference assessment and receiver-side interference monitoring and mitigation.
Language: English
Subfield: Aerospace Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
OpenAlex ID: W7204896376