A new multiple-access method based on FRACTIONAL FOURIER TRANSFORM

This paper introduces a new multiple-access technique named Frequency Band Width Division Multiple-Access (FBW-DMA). The proposed method processes signal in Fractional Fourier Transform (FrFT) domain to avoid some crucial problems in CDMA, such as high requirement of synchronization and suffering from single-frequency interference generated by other systems. By using chirp signals with different frequency band widths as carriers at the transmitter, the received signal is transformed into corresponding FrFT domain, then the narrow band matching coherent demodulation is used. Simulation results indicate that the proposed FBW-DMA achieves better Bit Error Rate (BER) performances compared with CDMA when serious single-frequency interferences exist, and the BER is lower one or two orders of magnitude.

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