A method and system of synchronizing two nodes of a network uses a demodulated output signal of a time division multiplex (TDM) demodulator to perform frequency and timing synchronization independently. Frequency synchronization is performed without using a program clock reference, by detecting a symbol timing loop error of the TDM demodulator. The error is filtered by an oscillator control loop filter if the error is within a predetermined range. Thus, an output voltage of a digital to analog converter that receives the filtered output controls an oscillator. In the timing synchronizer, an error between a program clock reference (PCR) and a value of a counter in the terminal is computed if the PCR is a not a first PCR, and the error is filtered with a timing loop control filter. A processor then adjusts a value of the counter in the terminal based on the filtered output.

Title
System and method of timing and frequency control in TDM/TDMA networks
Application Number
10/200450
Publication Number
20030147426
Application Date
July 23, 2002
Publication Date
August 7, 2003
Inventor
Ramakrishnan Balasubramanian
Gaithersburg
MD, US
Christopher J Cronin
Monrovia
MD, US
Agent
Sughrue Mion Pllc
DC, US
Assignee
Viasat
IPC
H04J 03/06
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