A wireless network device includes a signal receiving module that receives an RF signal, and a signal processing module that includes an automatic gain control (AGC) module and that generates control signals when a gain of the AGC module changes based on the RF signal. The network device includes a control module that selectively measures N time intervals between one of adjacent and non-adjacent control signals, wherein N is an integer greater than 1, and that selectively determines that the RF signal is a radar signal when the N time intervals are substantially equal.