A Comparison Of Transformed-Domain Techniques for Pulsed Interference Removal on GNSS Signals

It is well-known that GNSS receivers for aeronautical applications operating on the E5a/L5 frequency band have to deal with interfered signals due to the fact that this particular portion of the frequency spectrum is shared with other radio-aiding signals. Classical techniques, such as pulse-blanking, may turn out to be not effective in scenarios of multiple interfering sources. For this reason this paper focuses on a different class of techniques operating an invertible transform of the received signal. Such new representations of the signal allow decomposing the interfered received digital signal in a set of basis function providing a representation of the incoming signal in another domain where the interference can be better identified and removed. Description of these methods and their complexity will be presented when they are used to detect and remove pulsed interference. In particular, the Karhunen-Loève Transform (KLT) is introduced and a preliminary assessment of its performance for pulsed interference mitigation is provided.