Two new decision directed M-PSK timing error detectors

This paper shall introduce two new decision directed timing error detectors for symbol synchronization circuits in M-PSK receivers. The first detector is a modification of the Gardner timing error detector and requires a sampling rate of 2 samples/symbol. The second detector is a modification of the Mueller & Muller detector and requires 1 sample/symbol. The analysis of the detectors encompasses 1) computation of their S-curves, 2) computation of their tracking gains, 3) discussion of their hardware implementation, 4) evaluation of their timing-error variance, and, finally, 5) comparison of the detectors to the unmodified versions and to other timing error detectors, especially with regards to fading and resistance to automatic gain control circuit imperfections