Title :
Optimum and suboptimum frame synchronization for pilot-symbol-assisted modulation
Author :
Gansman, Jerome A. ; Fitz, Michael P. ; Krogmeier, James V.
Author_Institution :
Dept. of Electr. Eng., Maryland Univ., College Park, MD, USA
fDate :
10/1/1997 12:00:00 AM
Abstract :
Pilot-symbol-assisted modulation (PSAM) is a method to reduce the effects of fading in mobile communications by periodically inserting known symbols in the data stream. The receiver uses these pilot symbols to derive its amplitude and phase reference. One aspect of this procedure which has not received much attention in the literature is the method used by the receiver to locate the pilot symbols. This paper uses optimum frame synchronization techniques to develop two synchronizers for PSAM systems; one is based on a standard maximum likelihood (ML) estimation formulation, and the other is a sequential testing algorithm. Both methods use a simple quadratic correlation filter with an energy correction factor. Simulation results and a theoretical analysis are presented
Keywords :
Gaussian channels; Rayleigh channels; data communication; fading; land mobile radio; maximum likelihood estimation; mobile communication; phase shift keying; quadrature amplitude modulation; synchronisation; PSAM systems; amplitude; data stream; energy correction factor; fading; mobile communications; optimum frame synchronization; phase reference; pilot-symbol-assisted modulation; receiver; sequential testing algorithm; simple quadratic correlation filter; standard maximum likelihood estimation formulation; suboptimum frame synchronization; Demodulation; Error correction; Fading; Filters; Maximum likelihood estimation; Mobile communication; Sequential analysis; Standards development; State estimation; System testing;
Journal_Title :
Communications, IEEE Transactions on
