Optimizing GPS data transmission using entropy coding compression
Alberto González Villafranca, Iu Mora, Patrícia Ruiz-Rodríguez, J. Portell, Enrique García-Berro · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 2010
The Global Positioning System (GPS) has long been used as a scientific tool, and it has turned into a very powerful technique in domains like geophysics, where it is commonly used to study the dynamics of a large variety of systems, like glaciers, tectonic plates and others. In these cases, the large distances between receivers as well as their remote locations usually pose a challenge for data transmission. The standard format for scientific applications is a compressed RINEX file - a raw data format which allows post-processing. Its associated compression algorithm is based on a pre-processing stage followed by a commercial data compressor. In this paper we present a new compression method which can achieve better compression ratios with a faster operation. We have improved the pre-compression stage, split the resulting file into two, and applied the most appropriate compressor to each file. FAPEC, a highly resilient entropy coder, is applied to the observables file. The results obtained so far demonstrate that it is possible to obtain average compression gains of about 35% with respect to the original compressor.