An efficient demultiplexing algorithm for non-contiguous carriers

A channel separation algorithm for the FDMA/TDM (frequency division multiple access/time division multiplexing) scheme is presented. A demultiplexing algorithm that would allow demultiplexing of only the carriers of interest from the wideband spectrum of the FDMA signal in a random and efficient manner is proposed. The computational requirements indicate that the proposed technique of approximation and subsequent correction is efficient when only a small number of carriers need to be demultiplexed. When compared to the conventional fast transform algorithms (such as the FFT), the efficiency of the proposed algorithm decreases as the number of carriers increases. If the number of carriers to be processed is less than 20 (out of 800), then this demultiplexing algorithm is superior to the FFT. For an earth station application where the interest may be in only a few carriers out of hundreds received, the proposed demultiplexing algorithm is highly applicable