Performance comparison of graphical processing unit driven time-domain and FFT-based correlators for aircraft positioning system

The main goal of the paper is to present an analysis of the two baseband signal correlators. Correlation function is one of the fundamental tools being used in navigation radio signals processing. Among others it resolves signals for their mutual time delay which helps measure navigation parameters as DOA, TDOA or range. Therefore the importance of the correlator and effectiveness of its implementation increases. Powerful analytical method, correlation function can be tremendously time consuming to compute if pure sequential implementation and long signals with huge number of samples meet each other. The paper tries to scrutinize process of design of the correlator from perspective of its efficient implementation. Type of the implementation depends on the purpose of the correlator and its role in the system. There are explained details of both searching and tracking correlators. Couple of numerical experiments is presented to compare sequential schema of implementation in a CPU vs its parallel form in GPU processor.