A system for detecting interference includes an automatic gain control
(AGC) module, a digital signal processing (DSP) module, and a control
module. The AGC module selectively generates a gain-locked signal when an
input signal is received. The DSP module communicates with the AGC module
and selectively generates a sync-detect signal when the input signal is
received. The control module communicates with the AGC module and the DSP
module, and generates a control signal when the DSP module does not
generate the sync-detect signal within a predetermined time after the AGC
module generates the gain-locked signal.