Rear Cross-Traffic Alert (RCTA)
Rear cross-traffic alert (RCTA) warns about traffic approaching from either side while the vehicle is reversing, such as when backing out of a parking space. It commonly uses the rear corner radar sensors shared with blind-spot monitoring.
What it does
When the system predicts that a detected vehicle, cyclist, or other supported road user may cross behind the car, it can give a visual, audible, or haptic warning. Basic RCTA only alerts the driver. Rear automatic braking is a separate function, although some vehicles combine the two.
Parked vehicles, walls, vegetation, slopes, sensor dirt, and fast or small targets can restrict the field of view or affect detection. Supported target types and operating speeds vary. The driver must still look through the windows and mirrors, use the reversing camera, and stop whenever the path is uncertain.
For sensing geometry, alerts, and braking variants, see Rear Cross-Traffic Alert.