Transform Domain Communication System Based on Random-Ambiguity and Fractional Fourier Transform

Transform domain communication system (TDCS) using transform domain processing is demonstrated as having enhanced interference avoidance capability under adverse environmental conditions. Many transform methods can be used in the TDCS, a method is proposed in the paper which is based on random-ambiguity transform (RAT) plus fractional Fourier transform (FRFT). The proposed TDCS and its response to nonstationary interference scenarios are modeled and simulation results obtained using MATLAB. The proposed method has a good ability to anti any narrowband continuous nonstationary jammers. The system was evaluated using an E_b/N₀ of -7.0 dB and interference energy-to-signal energy (J/E) ratios ranging from 0 dB to 16.0 dB. For BCSK (binary cyclic shift key) data modulation cases, the average TDCS bit error performance improvement is more than 14 dB relatives to a DSSS system according to different J/E. Collectively, these results indicate that the proposed TDCS using RAT-FRFT for interference mitigating is a viable option in nonstationary jammers scenarios