An efficient multirate FDM demultiplexer for satellite communication systems

A new generation of "user-oriented" satellites with regenerative, on-board processing FDMA/TDM (frequency division multiple access and time division multiplexing) payloads has been proposed. A multicarrier demodulator (MCD) is required to interface the FDMA in the uplink and the TDM in the downlink. This paper presents the design of a polyphase-filter-FFT-bank (PFFB) demultiplexer as an efficient method for demultiplexing frequency slotted channels. It focuses on the analysis and evaluation of the system performance against the finite-word-length noise introduced in the fixed-point realization of the PFFB. The system signal-to-noise-ratio (SNR) and bit-error-rate (P/sub e/) are drawn from the finite precision simulations.