In the last years a number of conflict situations has clearly shown the importance of airspace dominance. The duel between hostile mobile antiaircraft defence and own airforce is therefor of great importance. In order to find the position of a mobile radar, a passive sensor can be used on a tactical aircraft. The estimated position can for example be used for SEAD, Suppression of Enemy Air Defence. Traditionally, systems for estimation of emitter positions required complex hardware, but new system architecture including advanced digital receiving processing has reduced the demands on hardware complexity extensively. This report starts with a description of an algorithm for emitter position estimation. It is based on accurate measurement of the emitter frequency and coarse measurement of the angle of arrival. Furthermore a number of parameters that effects the performance of the method is listed. Results from a measurement set-up are presented as well as results from computer simulations. The report also describes different aspects of the accurate frequency measurement method. The high performance of the algorithm used is a necessary condition for an accurate enough emitter position. The report is a description of the present status of the project. The research will continue during 2002