An Investigation on Number of Effective Taps for Multicarrier Schemes

In a wireless communication medium, the transmitted signal reaches to the receiver antenna after passing through multipath channel. The difference in path delays and mobility cause the transmitted signal spread both in time and frequency, resulting in inter-symbol (or adjacent block) and inter-carrier (or adjacent channel) interference, respectively. The pulse shaping and matching filters used in the transceivers also impact the level of dispersion in both time and frequency. In this study, the composite effects of wireless medium and the used filters are investigated on the equalization of multicarrier systems. For this purpose, considering a symbol-spaced tap model for the equalization, the number of effective taps in both time and frequency domains is obtained via Akaike information criterion (AIC) for different signal-to-noise ratios (SNRs). Subsequently, a method which characterizes the equalization complexity of the receiver as a function of the transmit pulse shape, communication medium, the receive filter response, and SNR is proposed.