A system includes a radio frequency transceiver. A baseband processor
includes an automatic gain control module. The automatic gain control
module has a gain that changes from and subsequently returns to a
predetermined value each time the radio frequency transceiver receives a
radio frequency signal. The baseband processor is configured to
selectively generate an interrupt signal each time a radio frequency
signal is received based on a magnitude of the change in the gain of the
automatic gain control module and a length of time in which the gain
returns to the predetermined value. A control module is configured to
identify a radio frequency signal received by the radio frequency
transceiver as a radar signal in response to the baseband processor
having generated a plurality of interrupt signals at substantially equal
time intervals.