Efficient Multitap Equalization For Fbmc-Oqam Systems

This work provides a simple yet efficient multitap equalization structure for filter bank multicarrier systems, which is a candidate waveform for the next generation (5G) of mobile communication systems. More specifically, we analyze the system performance under medium- to high-frequency selective channels. In this scenario, the single-tap equalizer is not enough to compensate the channel effects, and then, a multitap equalizer need to be deployed. In the literature, the available equalization structures that are more efficient in aggressive scenarios are generally quite complex, whereas the less complex alternatives do not perform satisfactorily in such conditions. In this context, we propose a new multitap equalization approach in the frequency domain, aiming at reducing the computational complexity while improving the system robustness against high-frequency selectivity conditions. For a wide range of number of taps and antennas, the proposed minimum mean square error-based frequency domain equalizer presents amuch reduced computational complexity, ie, less than 1% of the conventional minimum mean square error-based time domain complexity. The operation, advantages, performance, and the main differences between multitap equalization schemes against the simple one-tap equalizer for filter bank multicarrier systems are comprehensively discussed.