Patent ID: 7970071

Claim:
Method for carrier-frequency synchronization of a carrier signal influenced by a frequency and/or phase offset comprising estimating the frequency and/or phase offset of the carrier signal by estimating maximum-likelihood from a received signal with time-discrete complex rotary phasors, wherein only the time-discrete phases are dependent upon the frequency and/or phase offset, and wherein the received signal is an offset quadrature-modulated received signal, converting the received signal for the maximum-likelihood estimation via a first pre-filtering step into a modified received signal with time-discrete complex rotary phasors wherein the conversion of the received signal comprises a first sampling at two sampling values per symbol period, a complex multiplication, and a modulus-scaled squaring, the modulus-scaled squaring comprising implementing squaring and inverse modulus formation, and maximizing the real components of the complex rotary phasors for the maximum-likelihood estimation of the frequency and/or phase offset, wherein the conversion of the received signal is preceded by a demodulation, a second sampling, a second pre-filtering, and a clock-pulse synchronization.