| 摘要 |
A system, apparatus and method for providing phase lock conditions detection such as a quality of phase lock and loss of lock detection. A phase locked loop (PLL) circuit may comprise an oscillator for providing an output frequency, as well as a detector for detecting the output frequency of the oscillator, comparing the output frequency with a reference signal and outputting a first and second signals as a function of the comparison. The PLL circuit may further include an amplifying circuit for receiving the first and second signals, monitoring a deviation of the first and second signals from a predetermined threshold, and generating a third signal as a function of the deviation. The PLL circuit may further comprise a comparison circuit for receiving the third signal, comparing the third signal to a window threshold, and generating a fourth signal as a function of the comparison. The window threshold may be a function of apriori knowledge of at least one loop variable, wherein the window threshold is set based on a predetermined loop variable. An alarm circuit may receive the fourth signal and provide an alarm.
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