— In this paper1 an optimum and sub-optimum maximum likelihood (ML) rule for joint frame and carrier frequency offset estimation are derived, which rely on the transmission of a periodic pattern signal with an arbitrary number of periods and period length, embedded in the random data signal of a single user. Ad-hoc modification of the ML rule yields a robust metric for pattern search in a multi-user signal in a time division multiple access and time division duplex (TDMA/TDD) system, and a receiver with automatic gain control keeping constant average signal power at the synchronizer input. The mean, variance and Cramer-Rao Bound of the frequency offset estimate as well as the mean and variance of the frame estimate are theoretically evaluated and verified by simulation. The presented material proposes a unified framework for synchronization by periodic pattern signals and provides some new results, which are compared to known references.