Interference mitigation in spread spectrum systems by wavelet coefficients thresholding
Rene Jr. Landry, Philippe Mouyon, D. Lekaïm · European Transactions on Telecommunications · 1998
Abstract This paper studies a potential EMI (Electro Magnetic Interference) rejection technique for the GPS Standard Positioning Service in an avionics environment. Its generalisation to any Direct Sequence Spread Spectrum (DSSS) Systems is also considered. The paper gives a brief overview of Wavelet Theory, which is well established for noise reduction but which is applied here to Continuous Wave Interference (CWI) and narrowband interference. The originality of this work lies in a method for signal rejection, taking into account features in both time and frequency domains to account for the non‐stationary characteristics of the interference. Because the software‐based receiver is more flexible, less expensive and more accurate compared with typical hardware receivers, a Generic GPS Receiver has been implemented in software [1] to validate the antijamming technique developed in this paper. The aim of the Monte Carlo simulations is to get a good idea of the Performances of the Wavelet Filter against a various types of Interferences and to compare the results with traditional processing.