A new post-correlation anti-jamming technique for GPS receivers
- PDF / 3,029,052 Bytes
- 16 Pages / 595.276 x 790.866 pts Page_size
- 99 Downloads / 188 Views
ORIGINAL ARTICLE
A new post‑correlation anti‑jamming technique for GPS receivers M. Aghadadashfam1 · M. R. Mosavi1 · M. J. Rezaei1 Received: 13 December 2019 / Accepted: 26 June 2020 © Springer-Verlag GmbH Germany, part of Springer Nature 2020
Abstract Interference has destructive impacts on all signals, but due to the weakness of the global positioning system (GPS) signals, even low-power interference has a significant destructive effect. Mitigation of that effect is a challenging issue for GPS receivers. We investigate the performance of the acquisition in the presence of the most effective and common interferences in use, such as single-tone continuous wave interference (CWI), multi-tone CWI, and chirp jamming. Our purpose is not to mitigate or completely remove the interference signal, but by using a signal processing method after the correlation, a receiver can acquire weak signals in the presence of interference with a jammer-to-signal ratio up to 60 dB. The main idea is derived from image processing filters so that by applying proper filters to the values of the cross-ambiguity function in the search space, the interference signal contribution decreases without any need for prior knowledge of its specific characteristics. Accordingly, even weak GPS signals can be easily acquired, and the number of acquired satellites increases significantly compared to the usual anti-jamming methods. Moreover, signals can be acquired even at twice the normal decision threshold value. Keywords Denoising · Interference mitigation · Jamming · Acquisition · Post-correlation
Introduction GPS signals received in the front end of receivers are below the noise floor. That is why GNSS signals are very susceptible to noise and interference. Hence, interference mitigation and acquiring weak signals which are unrecoverable are an important issue for GPS receivers. Possible anti-jamming techniques to standard GPS receiver are categorized into two groups, which are named as post-correlation and precorrelation techniques (Trinkle and Gray 2001). Pre-correlation anti-jam techniques have a higher computational cost than the other group (Trinkle and Gray 2001). They can be applied as an external package to traditional GPS receivers and are classified into three main families based on what method is used: adaptive filtering techniques * M. R. Mosavi [email protected] M. Aghadadashfam [email protected] M. J. Rezaei [email protected] 1
Department of Electrical Engineering, Iran University of Science and Technology, Narmak, Tehran 16846‑13114, Iran
(Mosavi and Shafiee 2016; Amin et al. 1999), time–frequency filtering techniques (Rezaei et al. 2016; Mosavi et al. 2017), and antenna-level techniques (Li et al. 2011; Park et al. 2018). Pre-correlation techniques mostly mitigate narrowband jamming. Antenna-level methods can mitigate both wideband and narrowband interference, but they need additional hardware to implement. Adaptive filtering and time–frequency filtering techniques are low-cost methods. However, adapt
Data Loading...
