摘要 |
A frequency tracking circuit and method comprising a master crystal oscillator circuit is used for frequency tracking between a handset and a base station comprising a calibration subsystem for taking a temperature measurement, a reference control circuit for determining a numerical value needed to align a handset frequency with a base station frequency, an adder for adding the numerical value to a previous numerical value determined by the reference control circuit, a latch for latching the output of the adder, and a low precision master crystal oscillator for clocking the frequency of the latch. The most significant bit from the latch is input into a phase/frequency detector for forcing a voltage controlled oscillator to track a desired frequency.
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