High precision radio frequency direction finding system
High precision radio frequency direction finding systems are described that can determine an angle-of-arrival and geo-location of a RF emitter with respect to a mobile platform. A radio frequency direction finding (RFDF) system for determining a position of a RF emitter with respect to a mobile platform can include an angle-of-azimuth (AoA) system configured to determine an azimuth of a RF emitter with respect to the mobile platform; an attitude measurement system configured to measure the attitude of the mobile platform; a geo-location system configured to calculate the geo-location of the RF emitter; and a processor system configured to calculate a position of the RF emitter.
1. A radio frequency direction finding (RFDF) system for determining a position of a RF emitter with respect to a mobile platform, the system comprising:
an angle-of-azimuth (AoA) system configured to determine an azimuth of a RF emitter with respect to the mobile platform, wherein the AoA system comprises a RF interferometer;
an attitude measurement system configured to measure the attitude of the mobile platform;
a geo-location system configured to calculate the geo-location of the RF emitter;
a processor system configured to calculate a position of the RF emitter; and
an alignment system configured to align the RF interferometer.
2. The RFDF system of claim 1 , wherein the RF interferometer comprises an antenna array having a plurality of antennas.
3. The RFDF system of claim 2 , wherein the RF interferometer comprises a plurality of receivers, each connected to one of the plurality of antennas.
4. The RFDF system of claim 2 , wherein the RF interferometer comprises a plurality of phase comparators, each connected to one of the plurality of receivers.
5. The RFDF system of claim 3 , wherein each of the plurality of phase comparators is connected to a unique pair of the plurality of receivers.
6. The RFDF system of claim 2 , wherein the interferometer comprises a processor configured to implement the multiple signal classification (MUSIC) algorithm as an interferometry algorithm.
7. The RFDF system of claim 1 , wherein the attitude measurement system comprises a differential global position system (GPS) for determining the attitude of the mobile platform.
8. The RFDF system of claim 7 , wherein the differential GPS system is configured to determine the geo-location of the mobile platform.
9. The RFDF system of claim 1 , further comprising a database of topological data.
10. The RFDF system of claim 1 , further comprising a memory location including topological data.
11. The RFDF system of claim 1 , wherein the attitude measurement system comprises an inertial navigation system for determining the attitude of the mobile platform.
12. The RFDF system of claim 1 , further comprising one or more GPS receivers.
13. The RFDF system of claim 1 , wherein the alignment system comprises a built-in-test (BIT) system configured to align the RF interferometer.
14. The RFDF system of claim 1 , wherein the alignment system is configured to provide test waveforms to the RF interferometer.
15. The RFDF system of claim 1 , wherein the AoA system is configured to determine azimuth of the RF emitter utilizing phase measurements.
16. The RFDF system of claim 15 , wherein the AoA system is further configured to determine azimuth of the RF emitter utilizing amplitude measurements.
17. A radio frequency direction finding (RFDF) system for determining a position of a RF emitter with respect to a mobile platform, the system comprising:
an interferometer including an antenna array configured to determine an azimuth of a RF emitter with respect to the mobile platform, wherein the antenna array is configured for implementation on the mobile platform;
an attitude measurement system configured to measure the attitude of the mobile platform;
a geo-location system configured to calculate the geo-location of the RF emitter;
a geo-location system configured to calculate the geo-location of the mobile platform;
a processor system configured to calculate a position of the RF emitter with respect to the mobile platform; and
an alignment system configured to align the interferometer.
18. The RFDF system of claim 17 , wherein the interferometer comprises a processor configured to implement the multiple signal classification (MUSIC) algorithm as an interferometry algorithm.
19. The RFDF system of claim 17 , wherein the attitude measurement system comprises an inertial navigation system for determining the attitude of the mobile platform.
20. The RFDF system of claim 17 , wherein the attitude measurement system comprises a differential GPS system.