METHOD AND APPARATUS FOR LOCATING AND TRACKING A QPSK CARRIER

摘要

At the Power On Reset mode of the receiver, the search mode (201) is entered and the tuner AFC is swept in a search for the QPSK carrier. In the detect signal step (202), a low OOS signal is sought. If the low OOS signal is not found, the false lock detect step (205) checks to see if the AFC voltage is remaining constant. If it is, then the loop is broken in the break loop step (206). In the break loop step (206), the loop is held open for about 20 milliseconds, then the search mode (201) is entered again.