Conditioned pilots for ISI channels

One of the proposals to increase the spectral efficiency of the DVB-S2 standard is based on time-frequency packing. This technique causes intersymbol and interchannel interferences to arise, requiring a significant growth of the number of pilots used to carry out frequency and phase synchronization. Therefore, a new pilot design will be introduced and suited optimal and suboptimal reduced-complexity algorithms derived. We will show that the proposed pilot strategy may outperform the classical one in terms of bit error rate and spectral efficiency.