An enhanced police Doppler direction sensing radar detects possibly
dangerous traffic conditions during certain vehicle maneuvers such as
U-turns and returns to travel after roadside stops. By monitoring a host
or primary vehicle speed, speed transitions, transmission state (e.g.
gear selection), and the closing vehicle position, range and speed, a
number of selectable conditions are detected, resulting in an alert
indication to a primary vehicle operator. User preferences and thresholds
allow the traffic alert function to be customized according to a primary
vehicle operator's desire to suppress alerts in situations which the user
does not deem dangerous. The traffic alert function may be automatically
triggered under certain detected conditions, or manually initiated when
the primary vehicle operator intends to make a driving maneuver.