Radio frequency attenuator comprising a plurality of variable phase shifters and serially coupled directional couplers

摘要

A radio frequency attenuator including a ladder network made up of "N" serially coupled stages, each one of such stages having an output terminal coupled to a radio frequency source through a first and a second path, such second path having disposed therein a variable phase shifter. Included in each such stage is a load adapted to dissipate in the order of one Nth the power in the radio frequency energy. Each one of the phase shifters is responsive to a binary signal and the phase shift provided by each one of such phase shifters changes M 180 DEG in accordance with the binary signal (where M is an odd integer).