Transform domain communications and interference avoidance using wavelet packet decomposition

A recently proposed wavelet domain communication system (WDCS) using transform domain processing demonstrates enhanced interference avoidance capability under adverse environmental conditions. This work extends previous results by incorporating a wavelet packet based decomposition technique that permits demonstration of an M-ary orthogonal signaling capability and provides increased adaptability over a larger class of interference signals. The newly proposed WDCS and its response to various interference scenarios are modeled and simulation results obtained using MATLAB^®. Bit error rate is the key metric for analysis and performance comparisons. Relative to the non-packet based system, the packet based WDCS provides improved/comparable bit error performance in several interference scenarios - single-tone, multiple-tone, swept-tone, and partial-band interference. The system was evaluated using an E_b/N₀ of 4.0 dB and interference energy-to-signal energy (I/E) ratios ranging from 0.0 dB to 16.0 dB. For binary, 4-ary, and 8-ary CSK data modulations, the packet based WDCS exhibited average interference suppression capabilities of 6.7, 9.2, and 12.0 dB, respectively.