Low-cost digital correlator for frequency hopping radio

This paper presents a realization of digital correlator based on FIFO (First In First Out) buffer with significantly reduced hardware compared to previous hardware realization of PN (pseudonoise) correlator. The operation principle of proposed digital correlator is described. It is followed by the hardware solution for multichannel (multiple) programmable digital correlator which allows simultaneous correlations between multiple local PN sequences and receiving binary signal. Programmability is referred to a very simple method of selecting the length of sequences that are processed in the correlator without changing the hardware structure of the correlator at the same time. Furthermore, a scheme of correlator for very long sequence is given. Finally, correlator is verified through the practical measurements.