A method and apparatus are provided for imaging three-dimensional scenes and objects by detecting reflections from emitted sequences of electromagnetic radiation. At least one transmitter is provided for emitting a sequence of electromagnetic radiation, and at least three sensors are provided for detecting radiation reflected from the scene and objects being imaged. Signals based on the detected radiation are used, together with spatial information of the transmitters and sensors, to calculate reflectivity coefficients for points of interest in the scene. Velocity vectors associated with moving objects within the scene can also be determined based on the rate of change of the phase differences between the emitted and reflected radiations.