Over the past decade, many communication systems have transitioned to digital modulation from legacy analog waveforms, motivated by the potential for improved spectral and power efficiencies. Realization of these efficiencies requires digital signal processing approaches and algorithms. Digital communications has become one of the primary applications for signal processing technology research and development.

As an example, GIRD Systems has recently completed a contract with Air Force Research Labs (AFRL) in Rome, New York to develop wavelet packet-based multicarrier digital communications systems. By using wavelet packets as carrier waveforms rather than the conventional sinusoidal waveforms, significant performance improvements are possible with minimal increases in receiver complexity. The improvements are due to the uniquely simultaneous time- and frequency-localization properties of wavelet packets.