| 摘要 |
A symbol independent automatic frequency controller (100) includes a symbol correlator (110) for receiving a complex digital signal generated within a selective call receiver wherein the symbol correlator provides a real signal (114), an imaginary signal (116), and a magnitude signal (112), a discriminator (140) coupled to the symbol correlator for receiving and processing the real signal and the imaginary signal to provide a frequency error signal, a low pass filter (120) and comparison element (130) for filtering the magnitude signal and comparing the magnitude signal to a predetermined lock threshold signal that controls the bandwidth of the symbol correlator in the event the magnitude signal exceeds the lock threshold signal, and a feedback loop providing the imaginary signal (116) to an accumulator (170) and back to the symbol correlator wherein the accumulator provides the symbol correlator with an apriori-symbol phase feedback (172).
|
