| 摘要 |
A frequency-timing control loop comprising (1) a frequency control loop to acquire and track the frequency of a given signal instance in a received signal and (2) a timing control loop to acquire and track the timing of the same signal instance. The timing control loop processes data samples for the received signal to provide a first control indicative of timing error in the data samples for the signal instance. The frequency control loop includes (1) a frequency discriminator used to derive a second control indicative of frequency error in the data samples for the signal instance, and (2) a loop filter used to filter the first and second controls to provide a third control. This third control is used to adjust the frequency and phase of a periodic signal, which is used (directly or indirectly) to downconvert and digitize the received signal to provide the data samples. |
