Design of a General Pseudolite Pulsing Scheme

Pseudolites, or pseudo-satellites, are ground based transmitters of Global Navigation Satellite System (GNSS)-like signals. Pseudolite signal modulations often include a pulsing scheme that is adopted to reduce interference with non-participating GNSS receivers, mitigate the near-far problem and allow time division multiple access. For these reasons, an effective pulsing scheme design is crucial for the proper functioning of a pseudolite based system. In this paper, the requirements that a pseudolite pulsing scheme has to satisfy are at first identified and a general pulsing scheme based on random permutations is proposed. The spectral and temporal characteristics of the proposed scheme are determined and thoroughly analyzed. From the analysis, it emerges that the proposed scheme meets all the identified requirements making the suggested solution an effective tool for pseudolite signal design. Finally, the proposed approach is compared with a number of existing pulsing schemes from the literature and found to provide significant benefits with respect to most existing schemes.