A semi-active RF proximity fuze for warhead detonation is provided where external RADAR is available to illuminate the target. The fuze incorporates multiple receiving antennas with digital phase detection processing to distinguish the angle from which the target returns are received and uses that information to determine the detonation timing for the warhead. Detonation timing can be improved by processing the rate of change of the angle-to-target or processing the range and Doppler information to compensate for target velocity and distance.