Multi-channel direction finder according to the phase time difference interferometer principle

摘要

To minimise direction-finding errors which can occur when reception conditions are disturbed, particularly when several simultaneously incident coherent waves are received, the direction-finder concept is based on the amplitude-insensitive phase time difference interferometer principle in contrast to the direction-finding loop and Adcock principle or the sum/difference interferometer principle. In this arrangement, the received signals of the four individual antennas of the cross interferometer antenna system are first independently processed in four identical receiving channels, involving frequency conversion to an intermediate frequency in the kHz range. From the four intermediate-frequency signals, the respective signal phase differences of the pairs of received signals associated with the two orthogonal interferometer antennas are then simultaneously determined by means of two similar phase measuring devices operating in parallel. The phase is measured via the signal amplitude zero transition times directly coupled to the signal phase, which results in a phase-difference-proportional output signal of the phase measuring device in the entire phase range. The phase difference signal quantities thus generated, precisely corresponding to the right-angle components of the direction-finding vector, are finally optionally supplied to a screen display in azimuth angle representation or, after suitable analog/digital conversion, to a digitally computed right-angle polar coordinate converter, for evaluation. For ... Original abstract incomplete.