Wavelet packet division multiplexing (WPDM) is a multiplexing scheme in which the message signals are coded onto wavelet packet basis functions for transmission. A feature of WPDM is that the coding waveforms overlap in time and frequency, which can provide greater capacity and greater immunity to certain channel imperfections that time division and frequency division multiplexing. By analogy with frequency-hopped communication schemes, the WPDM scheme can be further enhanced by providing a framework for hopping the transmission parameters of the scheme in a pattern which is known by the receiver. In this paper, we exploit the underlying filter back structure of WPDM and the recent development of time-varying filter banks for signal analysis to provide a framework for slow wavelet packet hopping which does not compromise the data rate.
Tim N. Davidson,
Kon Max Wong,
"Wavelet-packet hopping", Proc. SPIE 2825, Wavelet Applications in Signal and Image Processing IV, (23 October 1996); doi: 10.1117/12.255262; https://doi.org/10.1117/12.255262