摘要 |
A radio direction finding system based on the doppler frequency shift principle is disclosed which utilizes a polygonal shaped antenna array and a conventional FM receiver. Voltages from each antenna are combined in an rf summing circuit which may be located remotely from the antenna. Audio output from the FM receiver is processed to measure the phase angle of the commutation frequency phase modulation imparted to the rf receiver input signal by gain variations within the rf summer circuit. Bearing angle proportional to the measured phase angle is displayed in a circular array of light emitting diodes and a three digit decimal display and is provided for recording or remote display through a serial interface.
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