Abstract: A system and method are provided for identifying the data rate of an input signal in a communications receiver. The method supplies a candidate frequency from a list of potential input data rate frequencies. A first test is performed, attempting to phase-lock a coded input data signal using a reference signal at the candidate frequency. If the input signal is phase-locked, a second test is performed of monitoring a phase detector output signal for the occurrence of a phase-lock interrupt. If a phase-lock interrupt is not monitored, a third test is performed of harmonic band detection. In response to passing the first, second, and third tests, the candidate frequency is selected as the reference frequency and the input data signal is decoded. If the first, second, or third test is failed, an alternate candidate frequency is supplied from the list and the tests are repeated, beginning with the first test.

Abstract: A system and method are provided for identifying the data rate of an input signal in a communications receiver. The method supplies a candidate frequency from a list of potential input data rate frequencies. A first test is performed, attempting to phase-lock a coded input data signal using a reference signal at the candidate frequency. If the input signal is phase-locked, a second test is performed of monitoring a phase detector output signal for the occurrence of a phase-lock interrupt. If a phase-lock interrupt is not monitored, a third test is performed of harmonic band detection. In response to passing the first, second, and third tests, the candidate frequency is selected as the reference frequency and the input data signal is decoded. If the first, second, or third test is failed, an alternate candidate frequency is supplied from the list and the tests are repeated, beginning with the first test.