Abstract: A solid state microwave switch having a plurality of adjacent parallel fingers covered with an oxide layer. One end of a finger is an N+ source region while the other end is an N+ drain region, with a current conducting N region between them. The oxide layer is covered with a gate layer to which a gate signal is applied for control of current between the N+ regions through the N region. The gate layer is highly resistive and has a sheet resistance on the order of millions of ohms per square. The length from the source to drain region is around 2 &mgr;m, and the fingers are spaced with a pitch of around 1 &mgr;m.

Abstract: An improved 180.degree. phase shifter bit that uses embedded switches to selectively connect the RF input and RF output to a loosely coupled transmission line segment and a pi section of transmission line. A hybrid coupler is selected having characteristic impedance of less than 50 ohms and having coupling of less than -3 db. The result of this coupling choice is extremely low insertion loss. The resultant impedance mismatch is compensated for by providing oversized field effect transistors that allow RF signal in both the grounded coupler and the pi section of transmission lines that are 180.degree. out of phase. The RF signal present in both the coupler and pi section of the transmission line results in a cancellation effect allowing recovery of the input/output impedance over an approximately one octave bandwidth.

Abstract: A miniature thin film microwave frequency acoustic filter device comprising acoustic resonators formed on the same dielectric membrane so that their frequency responses are identical. Because the filters are miniature, they can be manifolded without manifolding circuitry that normally causes significant filter losses.