for determining from a moving observer the location in terms of latitude longitude altitude and velocity of a stationary or moving radar emitting a pulsed or continuous wave signal the moving observer extracts from the radar signal significant electronic support measures parameters including frequency pulse repetition interval and pulse width and determines from those parameters whether a radio frequency or pulse repetition frequency measurement technique is appropriate and whether the radar signal angle of arrival must be computed the emitter location is computed using a ratio of sequential frequency measurements and the moving observer continues to collect frequency measurements until the location of the emitter can be established to within a predetermined degree of certainty application_number US 99650797 A description fig1 illustrates the special bearings only use of the invention aoas are produced using a modification of the technique described in commonly assigned patent application 34 apparatus for measuring moving emitter elevation and azimuth direction from doppler change measurement 34 ser no 08 800 561 as discussed therein if rf or prf measurements 101 and 102 are made sequentially during two constant velocity observer tracks then when relating the measurement m j 103 to the target kinematics 104 the emitter velocity 105 cancels from the doppler.