DocumentCode :
1417786
Title :
Maximum likelihood synchronisers with arbitrary prior symbol probabilities
Author :
Chiu, J.-H. ; Lee, L.-S.
Author_Institution :
Dept. of Electron. Eng. & Technol., National Taiwan Univ., Taipei, Taiwan
Volume :
138
Issue :
1
fYear :
1991
Firstpage :
50
Lastpage :
52
Abstract :
The likelihood function for carrier or symbol synchronisation problems with arbitrary prior symbol probabilities is derived using a new approach. The analysis indicates that the general structure of such a maximum likelihood (MAXL) synchroniser is the same as that of the conventional one with equal prior probabilities except for biasing the tanh operator input with a transition offset value nu , nu =(1/2) ln(q/p); here p is the prior probability of symbol ´1´, and q=1-p. For the case p=1/2, the general synchroniser is reduced to a conventional MAXL synchroniser, for instance the Costas loop carrier synchroniser or MAXL symbol synchroniser. But when there are no data transitions, i.e., p=1, or 0, the general synchroniser is shown to reduce to a phase-locked loop (PLL) for carrier synchroniser, or a PLL-type symbol synchroniser.<>
Keywords :
digital communication systems; phase-locked loops; synchronisation; Costas loop carrier synchroniser; arbitrary prior symbol probabilities; digital communication systems; maximum likelihood synchronisers; phase-locked loop; symbol synchroniser;
fLanguage :
English
Journal_Title :
Communications, Speech and Vision, IEE Proceedings I
Publisher :
iet
ISSN :
0956-3776
Type :
jour
Filename :
89038
Link To Document :
بازگشت