Analysis of HF data communication signals using the lag-windowed Wigner-Ville distribution

Abstract

Time-frequency analysis is used to analyze digital modulation signals such as FSK (frequency shift-keying) and ASK (amplitude shift-keying) in HF (high frequency) radio communications. A new time-frequency distribution, the lag-windowed Wigner-Ville distribution (LWWVD), improves the time-frequency representation by minimizing the interference terms due to the cross-term. Comparisons are made with the conventional Wigner-Ville distribution (WVD), reduced interference distributions (RID) and other related methods, based on the criteria of the mainlobe width and the signal-to-interference ratio. Consistently, the LWWVD gives the most accurate time-frequency representation for ASK and FSK signals.