Abstract: Low impedance means are provided for coupling a common circuit ground of a microwave circuit to the ground potential. The low impedance means include a plurality of resonators, each having a distinct resonant frequency at which it displays a minimum impedance. The resonant frequencies of the resonators are chosen and arranged such that the resonators together operate to provide a low impedance band in the frequency spectrum within which low impedance coupling between the common circuit ground and the ground potential is achieved. In a preferred embodiment, resonators include capacitors connected in series with inductive bonding wires, and different resonant frequencies are obtained by using capacitors with different capacitance.

Abstract: A monolithic double balanced mixer with a high third order intercept point employs a local oscillator signal which is applied to the input port of a first active distributed element balun. The balun has two outputs which are applied via amplifiers to respective inputs of a double balanced resistive FET quad mixer. The double balanced resistive FET quad mixer employs four MESFETs arranged in a ring configuration. Two additional inputs to the quad mixer are obtained from a second balun which is also of an active distributed element configuration and receives at the input the RF signal. The quad mixer operates to produce mixing of the LO and RF signals at the outputs thereof. The outputs of the quad mixer are applied to a combiner which operates to combine the outputs of the quad mixer to produce at the combiner output an IF signal. The combiner can be a common gate combiner configuration with active loads or a distributed configuration employing FET devices in a distributed transmission line type of circuit.