Abstract: A coupled resonator filter oscillator having an impedance matching network coupled between an amplifier and a filter. The impedance value of the amplifier varies due to amplifier gain compression. The network maintains a constant impedance to the filter when said amplifier's impedance changes to preserve the filter's original transfer function.

Abstract: A surface acoustic wave device employs in-line input and output transducers disposed on a piezoelectrically active surface. Two U-configured multi-strip couplers are disposed between the input and output transducers in an overlapped, opposing configuration in order to convolve the side lobe energy from the input transducer across substantially all of the aperture of the output transducer.

Abstract: A surface acoustic wave (SAW) waveguide-coupled resonator filter is overcoupled to produce an essentially constant conductance and susceptance over at least the bandwidth of a desired notch filter. The SAW resonator filter is embedded in a bridged-T allpass circuit to provide the pair of equal capacitances of the circuit, and the resonator ground is connected to one terminal of the parallel inductor of the circuit having the other terminal connected to a system ground.

Abstract: An environmental control apparatus for electronic circuit elements includes an enclosure for the element and standoff brackets supporting the enclosure, the enclosure and support brackets together defining an area of both high heat resistivity and high heat conductivity, with a heating mechanism with the area of high heat conductivity in order to reduce the flow of heat and to maintain a balanced temperature profile along the enclosure.

Abstract: A surface acoustic wave device in a piezoelectric medium includes input and output transducers for launching and detecting a surface acoustic wave along the piezoelectric medium. The device is arranged in a ring loop to process the bidirectional acoustic wave launched from the input transducer. Multistrip couplers in the ring loop between the input and output transducers are used to achieve low loss characteristics. A phase shift introduced by the multistrip couplers between portions of the surface acoustic wave is used to cancel triple-transit reflections.