Title :
Estimation of clock skew in telephony over packet switched networks
Author_Institution :
Ericsson Radio Syst. AB, Stockholm, Sweden
Abstract :
This study deals with some synchronization issues occurring in telephony over asynchronous packet switched networks. A method for estimation of clock skew i.e. difference between the transmitter and receiver clock frequencies is described. The method is based on modeling the clock skew as a linear trend and the network delay jitter as an exponentially distributed i.i.d. random process. The corresponding maximum likelihood parameter estimator of the trend and jitter parameters is derived and expressions for the mean squared estimation error are provided. Simulation results for computer generated data and for delay data recorded in some existing networks are given
Keywords :
exponential distribution; jitter; maximum likelihood estimation; mean square error methods; packet switching; random processes; switching networks; synchronisation; telephony; asynchronous packet switched networks; clock skew estimation; computer generated data; delay data; exponentially distributed i.i.d. random process; jitter parameter; linear trend; maximum likelihood parameter estimator; mean squared estimation error; network delay jitter; receiver clock frequency; simulation results; synchronization; telephony; transmitter clock frequency; Clocks; Frequency estimation; Frequency synchronization; Jitter; Maximum likelihood estimation; Packet switching; Parameter estimation; Random processes; Telephony; Transmitters;
Conference_Titel :
Acoustics, Speech, and Signal Processing, 2000. ICASSP '00. Proceedings. 2000 IEEE International Conference on
Conference_Location :
Istanbul
Print_ISBN :
0-7803-6293-4
DOI :
10.1109/ICASSP.2000.860999
