Principles of independent receivers for use with co-operative radar transmitters

The paper describes the radar configurations known as bistatic and multistatic, in which one or more receivers are situated remotely from a radar transmitter, but operate in co-ordination with the transmitter to provide range and bearing information for targets illuminated by the transmitter beam. The advantages of such passive, remote receiver installations are discussed. The main part of the paper is devoted to two topics: a description of ways in which the necessary synchronization reference signals may be provided to the receiver without the need for any fixed telecommunication link between transmitter and receiver; a description of the way in which target range and bearing information in bistatic systems may be obtained by fast, real-time, numerical solution of the bistatic geometrical relationships. An experimental, totally-independent, bistatic receiver using the transmissions from a u.h.f. air traffic control radar is then described and its performance discussed. The paper concludes with mention of future work with such a receiver, to include the provision of moving target information and a multiple-beam phased-array receiving antenna.