Desarrollo de un algoritmo de la técnica de espectro ensanchado en Matlab para evaluar el rendimiento del canal de transmisión en GPS L1.

Abstract

An algorithm was designed and assessed by means of Matlab software for performance measurement of the transmission cannel by implementing the spread spectrum technique on a global positioning system (GPS) L1, in addition to applying channel coding techniques to protect the security of the information transmitted. The methodology used was a quantitative descriptive type by which the algorithm was developed in three main blocks representing the process carried out during the transmission and reception of a GPS L1 system which are: Transmission Stage (Signal Generation GPS L1 and encoding information), creation of transmission channels (Rayleigh, Rician and Additive White Gaussian Noise (AWGN)) and Reception Stage (Decoding and information Retrieval). Handled tools for the development of the algorithm consists of Matlab software and computer. The results obtained after the measurements carried out determined that the application of the spread spectrum technique allows decreasing the spectral power density achieving a noise immunity at the expense of requiring a bandwidth of 2 MHz much greater than the one originally used. In addition, it was determined that the algorithm of error detection and correction with higher robustness against the introduced noise was the convolutional one (2, 1, 3). The algorithm implemented in Matlab allows to determine the compartment of the Direct Sequence Spread Spectrum (DS-SS) technique applied to GPS L1, besides establishing the most optimal detection and correction algorithm. It is recommended for future research, to use high capacity computers for the processing of this type of signals in Matlab software because they are systems that work at a high frequency of operation, so a lot of data to be processed due to the number of samples generated.