A Telegoniometer (a type of Goniometer) is a device for varying the phase relationship(s) among two or more antennae, in an array for purposes of steering the directionality of the array, without physically moving the antennae. This is commonly used for radio direction finding, providing very precise bearings from a sensitive fixed site.
A Telegoniometer is simply a Goniometer with remote control and readout, for instance, as used on unmanned spacecraft for the long-range approach phase of automated docking, before more precise (but shorter-range) optical systems take over.
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