Adaptive multiwavelet packet modulation for channels with time-frequency localized interference

In this paper, the time-frequency (T-F) analysis is used to model in wireless channels the additive interference and noise which is classified into global and local types. Global noise, such as the additive white Gaussian noise (AWGN), has a power distributed at all signaling frequencies for all times, whereas local noise, such as the impulsive noise (IN) and narrow band interferences (NBI), has a localized compact spread in the T-F plane. Within this framework, a general T-F tiling-based block transmission scheme is proposed that implements the modulation to match the channel distortion by avoiding transmission in the corresponding T-F signaling units. Specifically, based on the multiwavelet packet (MWP) theory, a novel multiwavelet packet modulation (MWPM) with a flexible dyadic structure and its adaptive extension are developed. The performance for the adaptive MWPM with GHM MWP and BPSK in each subcarrier is evaluated to show the robustness of the proposed scheme in channels corrupted by the T-F localized interference/noise.