Abstract: A coherent TOA system is provided for rapidly ascertaining the position of a pulse train emitter such as a radar. Techniques are provided to estimate the underlying repetition interval of the emitter and to do the TOA processing knowing which of the particular pulses is being detected at a collector, thus surmounting the effect of gaps in the received pulse stream. The subject system is preferable to conventional time-difference-of-arrival geolocation systems which require that each of the collecting platforms measure the same pulse from the emitter, and also to non-coherent TOA systems whose accuracy is less than that achievable with the subject coherent system for the same amount of data.

Abstract: A coherent TOA system is provided for rapidly ascertaining the position of a pulse train emitter such as a radar. Techniques are provided to estimate the underlying repetition interval of the emitter and to do the TOA processing knowing which of the particular pulses is being detected at a collector, thus surmounting the effect of gaps in the received pulse stream. The subject system is preferable to conventional time-difference-of-arrival geolocation systems which require that each of the collecting platforms measure the same pulse from the emitter, and also to non-coherent TOA systems whose accuracy is less than that achievable with the subject coherent system for the same amount of data.

Abstract: A system is provided for rapidly ascertaining the position of a pulse train emitter such as a radar using multiple collectors without requiring more than one platform to measure the same pulse. Thus time-of-arrival measurements at a number of collecting platforms are performed, with the positions of the platforms being accurately ascertainable using GPS data, and with time synchronization between the spaced-apart collectors performed by utilizing atomic clocks. In the multi-ship case, geolocation can be performed on ten milliseconds of data as opposed to 30 seconds of data for measurements involving a single platform. The subject system is preferable to conventional time-difference-of-arrival geolocation systems because those systems require that each of the collecting platforms measure the same pulse from the emitter, which severely constrains the flight paths of the collectors, limits the amount of usable data, and increases the system's sensitivity requirements.

Abstract: A method and system to rapidly, passively, estimate target range, speed and heading for non-maneuvering and maneuvering radio frequency airborne emitters (enemy targets and threats) for tactical fighters using batch based recursive estimators for track initialization and track maintenance that includes providing information processing that operates on interferometer cosine (cone angle) measurements, and estimated SNR (signal-to-noise ratio) data, threat database, and feedback information from pilot maneuver cue algorithm. The present method will initialize airborne tracks using varying degrees of real time and a priori information to quickly estimate coarse airborne emitter heading using real time interferometer cosine (cone angle) measurements and provide pilot aircraft maneuver cues that will accelerate passive range (target speed and heading estimates) convergence.

Abstract: A method and system to rapidly, passively, estimate target range, speed and heading for non-maneuvering and maneuvering radio frequency airborne emitters (enemy targets and threats) for tactical fighters using batch based recursive estimators for track initialization and track maintenance that includes providing information processing that operates on interferometer cosine (cone angle) measurements, and estimated SNR (signal-to-noise ratio) data, threat database, and feedback information from pilot maneuver cue algorithm. The present method will initialize airborne tracks using varying degrees of real time and a priori information to quickly estimate coarse airborne emitter heading using real time interferometer cosine (cone angle) measurements and provide pilot aircraft maneuver cues that will accelerate passive range (target speed and heading estimates) convergence.