However, at high SNR, the optimized SINR converges to the optimized SIR value obtained for a noiseless channel (i.e., [N.sub.0] = 0).
The sensitivity of POPS-FBMC on hexagonal and rectangular lattices to time synchronization errors is shown in Figure 12(a), when the normalized time synchronization error [DELTA][tau]/Ts varies between -40 and 40, for a lattice density [DELTA] = 0.8, waveform durations D = 3T and 7T, and a noiseless channel. Contrarily to the sensitivity to frequency synchronization errors, the POPS-FBMC with hexagonal lattices is more sensitive to ISI over a time dispersive channel than the POPS-FBMC with rectangular lattices, especially for large waveform durations.