Jitter-reduced digital timing recovery for multilevel PAM and QAM systems

In multilevel pulse amplitude modulation/quadrature amplitude modulation (PAM/QAM) systems, e.g., digital radio, there is a strong demand for a reliable and precise timing phase provided by the timing recovery circuit. A phase detector that is theoretically jitter free, even in the case of noncoherent demodulation, is presented. In practical applications, with reduced complexity, a jitter reduction on the order of >15 dB is achieved. Solutions to improve the behavior of the timing recovery in case of linear channel distortions are given