Title :
Rapid carrier acquisition from baud-rate samples
Author :
Yuan, W. Shaw ; Georghiades, Costas N.
Author_Institution :
Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA
fDate :
4/1/1999 12:00:00 AM
Abstract :
Maximum-likelihood estimation of phase and frequency offset involves the maximization of a nonlinear likelihood function. We develop an estimator for carrier acquisition by linearizing the likelihood-function, and show that its performance is close to the Cramer-Rao bound (CRB). The estimator is then extended to blind frequency acquisition and combined with testing to eliminate unlikely hypotheses. With proper modeling of the likelihood resulting from the blind search, simulations show that the algorithm quickly rejects all but the correct frequency hypothesis
Keywords :
filtering theory; frequency estimation; least squares approximations; matched filters; maximum likelihood estimation; nonlinear functions; phase estimation; quadrature amplitude modulation; recursive estimation; search problems; signal sampling; synchronisation; CRB; Cramer-Rao bound; QAM; TDMA; baud-rate samples; blind frequency acquisition; frequency estimator; frequency hypothesis; frequency offset; least squares estimator; linear likelihood function; matched filter samples; maximum-likelihood estimation; nonlinear likelihood function; performance; phase offset; rapid carrier acquisition; recursive estimation; simulations; testing; Frequency estimation; Iterative algorithms; Maximum likelihood estimation; Phase detection; Phase estimation; Phase frequency detector; Phase measurement; Phase shift keying; Quadrature amplitude modulation; System performance;
Journal_Title :
Communications, IEEE Transactions on