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Mitigation of chirp interference in NavIC signals using NWPR and SNV estimator

  • Divyasree Uddandapu and Surya Narayana Murthy Tummala ORCID logo EMAIL logo
Published/Copyright: September 23, 2025
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Abstract

Radio Frequency Interference (RFI) makes it very difficult for Global Navigation Satellite Systems (GNSS) signals to work properly and remains safe. This makes positioning less accurate and reliable. This study looks at the current methods for finding and reducing RFI, with a focus on the IRNSS S-band and L5-band, because it covers the whole world. In this, how the chirp interference affects signal tracking by measuring the Carrier-to-Noise Ratio (C/N 0) using in-phase and quadrature-phase correlator outputs under both statistical and estimated settings. The narrowband-wideband power ratio (NWPR) approach boosts effective C/N 0 by 11.37 dB-Hz for the S-band signal and 12.48 dB-Hz for the L5-band signal, and compares it to the statistical C/N 0 value and the Signal to Noise variance estimator C/N 0.

Keywords: RFI; GNSS; IRNSS; C/N 0 ; NWPR; SNV

Corresponding author: Surya Narayana Murthy Tummala, Department of ECE, JNTU-GV College of Engineering Vizianagaram, Vizianagaram, India, E-mail:

Acknowledgments

We are grateful to Dr. D. Venkata Ratnam, M.Tech., Ph.D, Professor and Head – Research, Department of Electronics & Communication Engineering, School of Electrical Sciences, KL Deemed to be University, Andhra Pradesh, INDIA, for his valuable guidance and insightful discussions on radiosonde data analysis.

  1. Research ethics: Not applicable.

  2. Informed consent: Not applicable.

  3. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and approved its submission.

  4. Use of Large Language Models, AI and Machine Learning Tools: None declared.

  5. Conflict of interest: The authors state no conflict of interest.

  6. Research funding: None declared.

  7. Data availability: Not applicable.

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Received: 2025-06-12
Accepted: 2025-07-24
Published Online: 2025-09-23

© 2025 Walter de Gruyter GmbH, Berlin/Boston

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