ICI Reduction Through Shaped OFDM in Coded MIMO-OFDM Systems
The default pulse shaping filter in the conventional Multiple-Input and Multiple-Output (MIMO) based Orthogonal Frequency Division Multiplexing (OFDM) system is a rectangular function, which unfortunately is highly sensitive to frequency synchronization errors and the Doppler spread. Shaped OFDM is able to considerably alleviate the effect of Inter-Carrier Interference (ICI) as well as reduce the out-of-band frequency leak. In this paper, the authors study various pulse shaping functions and investigate their efficacy for reducing the ICI in the space-time block coded MIMO-OFDM system. They compare a new shaping pulse termed harris-Moerder pulse with several other popular Nyquist pulses such as the raised-cosine pulse and better than raised-cosine pulse.