The simulating model of system of an OFDM broadcast of signals is considered when using on each subcarrier frequency of optimum spectral-effective signals. Two methods of reception of these signals are considered: algorithm of coherent optimum bit-by-bit reception and algorithm of Viterbi. Graphs of dependences of error probability of signals reception on these methods from the relation a signal noise for the channel with constant parameters and additive normal white noise are received.