Detection and Mitigation of GNSS Interference for Robust Navigation and Timing

  • Elizabeth Lloyd

Student thesis: Doctoral ThesisPhD


GNSS have been operational since the mid 1990s, and are now ubiquitous in modern life. Aside from the obvious positioning and navigation applications, it is also widely used for timing applications such as in communications and power distribution networks. The design of GNSS means the signals are weak, making them vulnerable to interference. This can be intentional or unintentional. Locating the source of intentional jamming is of particular interest as it is often associated with other criminal acts like car theft and drug dealing. Jamming detection and localisation systems already exist. However, none of those on the
market today are low power and low cost, as well as capable of real time localisation of the jamming source, which is vital for mitigation of interference.

In this Thesis, the design, manufacture and real world testing of a system for GNSS jamming detection is demonstrated. The system relies on simple beamforming techniques, providing significant cost and power savings over the usual mathematical methods used for determining direction of arrival. To improve the efficiency of the search, bio-inspired algorithms are used. They are modified to allow tracking of a moving signal. Finally, they are implemented on an FPGA. The entire system, comprising antenna, digitally controlled beamformer, FPGA and real time data logging is demonstrated tracking a moving jammer in a real world scenario.
Date of Award10 Dec 2020
Original languageEnglish
Awarding Institution
  • University of Bath
SupervisorRobert Watson (Supervisor) & Cathryn Mitchell (Supervisor)


  • GNSS
  • GPS
  • Jamming
  • Spoofing
  • PNT
  • bio-inspired
  • invasive weed optimisation
  • IWO
  • particle swarm optimisation
  • PSO
  • FPGA

Cite this