A broadside array antenna arrangement capable of scanning electronically in one or two planes, wherein the transmitted or received frequency remains fixed although beam steering is effected by progressive phase shifts introduced to the various array elements as provided by the expedient of frequency variations. A prime oscillator frequency fo is mixed with a variable steering oscillator frequency fs to produce sum and difference frequencies fo + fs and fo - fs. The latter is fed to a delay line having a plurality of taps spaced apart in accordance with the particular arrangement of array elements, the delay line providing in the frequency signal fo - fs progressive phase shifts from tap to tap. The individual tap outputs are separately mixed with the sum frequency signal fo + fs, wherein N separate outputs are simultaneously derived having the same frequency of 2fo but varying from one another progressively in phase. Variation of fs, which causes the phase relationship between the N outputs to change as they are fed to the radiators in one-to-one correspondence, thus provides a sweep of the beam in one plane. Raster type scanning is provided by introducing a multi-tapped secondary delay line at each tap of the primary delay line and mixing instead the tap outputs of each secondary delay line individually with fo + fs and applying the resultant 2fo outputs to individual ones of a corresponding element row of a two-dimensional array. The tapped spacings on each of the secondary delay lines relative to the tapped spacings of the primary delay line is such as to provide scanning of an order of magnitude more sensitive in one plane.
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