Abstract: An amplitude responsive detection system analyzes the amplitude characteristic of a received noise and determines whether that characteristic conforms to the predictable audio signature of a gunshot. If a received noise reaches a predetermined amplitude level within a rise time that may be indicative of a gunshot, subsequent amplitude criteria are established representing the decay of the amplitude profile that is expected if the noise is a gunshot. The amplitude criteria are controlled as to both level and occurrence in time to provide a dynamic range that will accommodate near and far gunshots.

Abstract: A traffic radar unit capable of looking past the lead vehicle of oncoming traffic and discovering and identifying a violator employs master and slave antennas having diverging boresights that provide overlapping relative power density radiation patterns. The radar return signal from a target of interest is received by each antenna to produce two independent Doppler signals of the same frequency which are processed by respective master and slave signal processing channels. In the illustrated embodiment, a reference boresight is established in the overlapped patterns such that a target position along the reference boresight occurs at the time that the amplitudes of the two Doppler signals are equal. Controllable high pass filters whose passbands are shifted upwardly in response to return signals of increasing amplitude attenuate stronger, lower frequency interfering signals.

Abstract: A one-piece traffic radar unit has a housing containing both the transceiver and signal processing circuitry and the directional antenna of the radar system. A bracket plate extends from the top portion of the housing and overlies the dashboard of the patrol vehicle to mount the unit therein with the housing depending from the bracket plate in front of the dashboard, thereby leaving the driver's view through the windshield unobstructed. The antenna is of the conical horn type and is vertically disposed to beam the transmitted signal up through the housing to a rotary reflector mounted on the top of the housing. The reflector is rotatable about a vertical axis and permits the operator to aim the beam in any horizontal direction through the windshield or a window of the vehicle. A special safety mount for the reflector provides for 360.degree. rotation and also permits the reflector to break away from the housing on impact.