... the same radio frequency bands, i.e., VHF/UHF bands III, IV, and V.Hence, the DVB-T and DVB-RCT systems may form a bi-directional FDD communicationsystem which shares the same frequency bands ... applying phase diversity is shown in Figure 6 -9. In order to achieve frequency selective fading within the transmission bandwidth of theNcsub-channels, the phase m,nhas to fulfill the conditionm,n2πfnB2πnNc(6.10)OFDM01M ... anAWGN channel. This improves the power efficiency. However, there are two ways toincrease the spectral efficiency. The first one, which is the trivial way, is to increase thesymbol alphabet size and...