Low loss RF phase shifter with flip-chip mounted MEMS interconnection

A phased array antenna comprising:

• a substrate;
• a plurality of radiators disposed on the substrate;
• a plurality of passive phase shifter circuits disposed on the substrate, each of the plurality of phase shifter circuits being coupled to one of the plurality of radiators and comprising a plurality of phase delay stages connected in series between a transmission signal input and a transmission signal output to phase shift said signal, each of the phase delay stages being capable of imparting a selectable phase delay on a transmission signal so that the signal is delivered to the radiator with a cumulative phase delay determined by the sum of the phase delays imparted by the individual phase delay stages;
• and
• a plurality of MEMS switch modules, a respective one of said MEMS switch modules being coupled to each phase delay stage and operable to electrically connect selected delay stages to provide said cumulative phase delay, the respective MEMS switch modules being coupled to said phase delay stages by low loss interconnections, the low loss interconnections comprising flip-chip interconnections.