A radiation source location technique includes focusing a plurality of receivers (i.e., antennas) at the same location. At least one determined characteristic of the radiation received at each receiver provides information regarding the source of that radiation relative to each receiver. Determining a relationship between the determined characteristics allows for determining when the source of radiation is at the location where the receivers are focused. One example includes using high directivity, narrow beamwidth antennas and time based markers from a wireless digital communication signal for locating a mobile unit source of radiation.