Periodic Sequences with Optimal Properties for Channel Estimation and Fast Start-Up Equalization

The problems of fast channel estimation and fast start-up equalization in synchronous digital communication systems are considered from the viewpoint of the optimization of the training sequence to be transmitted. Various types of periodic sequences having uniform discrete power spectra are studied. Some of them are new and may be generated with data sets commonly used in phase modulation systems. As a consequence of their power spectra being flat, these sequences ensure maximum protection against noise when initial equalizer settings are computed via channel estimates and noniterative techniques.