GNSS Spoofing Mitigation in Multipath Environments Using Space-Time Processing

Civilian GNSS signal structures are publicly known and they are received with low power on the earth surface. These make GNSS signals susceptible to spoofing attacks. Hence, the requirement for proper mitigation techniques becomes a must in current and future GNSS receivers for robust, accurate and reliable positioning. This paper proposes a new antispoofing technique using an antenna array in multipath environment where several reflections of the spoofing signal are also received by the array. A spatial processing approach in conjunction with a time domain processing method is utilized to estimate spoofing channel coefficients, which then can be employed to nullify the spoofing signal and its reflections. The effectiveness of the proposed algorithm is evaluated using several simulations. In addition, the signal to spoofing-plus-noise ratio (SSNR) versus the injected spoofing power is evaluated to demonstrate the performance of the proposed method for different spoofing power levels. The simulation results show the ability of the method to mitigate the spoofing signal in multipath environments. In order to demonstrate the applicability of the proposed method, a real data is collected and processed to model a multipath spoofing scenario. BIOGRAPHIES Dr. Saeed Daneshmand obtained the Ph.D. degree in the PLAN Group of the department of Geomatics engineering at the University of Calgary. He holds his M.Sc. degree in Telecommunication engineering from the Amirkabir University of Technology (2008) and his B.Sc in Electrical engineering from the IUST University (2006). He is a Senior Research Associate/Post-Doctoral Fellow in the Position, Location and Navigation (PLAN) group of University of Calgary. His current research focuses on signal processing, interference mitigation and antenna array processing in GNSS applications. Ali Jafarnia Jahromi received his B.Sc. and M.Sc. degrees in Telecommunications engineering from Amirkabir University of Technology, in 2006 and 2009 respectively. He is currently a Ph.D. candidate at the Position, Location and Navigation (PLAN) group of Geomatics Engineering Department of University of Calgary. His research interests include signal processing in GNSS applications, array processing, statistical signal processing and GNSS receiver design. Dr. Ali Broumandan holds his M.Sc. degree from the department of Electrical and Computer engineering, University of Tehran. He obtained the Ph.D. degree in Geomatics engineering department at the University of Calgary. From October 2009 to April 2012 he was a senior research associate in the PLAN group of the University of Calgary, Canada. Since May 2012 he is involved in a GNSS industry. His current research focuses on GNSS signal processing, array processing, detection, and estimation theory. Professor Gérard Lachapelle holds a Canada Research Chair in Wireless Location in the Department of Geomatics Engineering where he has been a professor since 1988. He has been involved in a multitude of Global Navigation Satellite Systems (GNSS) R&D projects since 1980, ranging from RTK positioning to indoor location and GNSS signal processing enhancements.