Characterization of Ping-pong Optimized Pulse Shaping-OFDM (POPS-OFDM) for 5G systems

Due to high mobility situations that are commonly envisaged for the next Fifth Generation (5G) of mobile communication systems, the wireless propagation channel becomes a time-frequency variant, where the time dispersion emerges from the multipath characteristic and the time-selectivity arises from the Doppler spread. This aspect can dramatically damage the waveforms orthogonality that is induced in the Orthogonal frequency division multiplexing (OFDM) signal. Consequently, this results in oppressive Inter-Carrier Interference (ICI) and Inter-Symbol Interference (ISI), which leads to performance degradation in OFDM systems. To efficiently overcome these drawbacks, we propose Ping-pong Optimized Pulse Shaping-OFDM (POPS-OFDM) algorithm that maximizes the received Signal to Interference plus Noise Ratio (SINR) by optimizing systematically the OFDM waveforms at the Transmitter (TX) and Receiver (RX) sides. We derived the exact closed-form expression of the SINR of the considered multicarrier system and the optimized waveform is searched as a linear combination of several of the most localized Hermite functions. Then, we go further by testing its robustness against time synchronization errors. The results confirm the advantage behind POPS-OFDM algorithm in enhancing spectacular performance and its robustness compared to multicarrier systems using conventional waveforms. Simulations are given to support our claims.