| 摘要 |
The invention is embodied in a digital direction finding receiver having N frequency channels (50a, 50e) spanning a frequency band of the receiver and capable of receiving signals simultaneously from a plurality of antennas (30a, 30e) spaced from one another, one of the antennas including a reference location antenna. The receiver of the invention includes a plurality of analog-to-digital converters (32a, 32e) having their analog inputs connected to respective ones of the antennas, a reference source (58) capable of outputting a reference digital signal containing at least a local frequency component within a selected one of the N frequency channels, a plurality of digital down converter modules (50a, 50e), each one of the digital down converter modules having a reference input connected to the reference source and a signal input connected to the digital output of a respective one of the analog-to-digital converters, each the digital down converter modules including a multiplier (56a, 56e) for producing at an output of the digital down converter a product of the reference signal and the signal from the respective one of the antennas, and a digital phase detector (35) having plural phase detector signals inputs connected to the outputs of remaining ones of the digital down converters, the phase detector detecting phase angles of the signals on each of the phase detector signal inputs relative to a corresponding signal received at the reference antenna.
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