Method for measuring angular direction of object e.g. car, involves receiving second echo from object, and computing angular direction of object based on measurements of echoes

摘要

The method involves transmitting a signal such as electromagnetic signal or acoustical signal. A first echo of the signal is received from the object (213). The first echo is returned towards the object. A second echo is received from the object. An angular direction of the object is computed based on measurements of the first echo and the second echo. The first echo is actively or passively repeated. The measurement of first echo or of the second echo is provided with time measurement or a frequency measurement. An independent claim is included for an apparatus for measuring angular direction of object.