A millimeter wave microstrip shunt-mounted PIN diode switch having its DC ground separate from RF ground is created by utilizing a fan structure (radial stub) having a radius of approximately one-quarter wavelength to provide an RF ground at that location and then coupling the DC bias supplies to that RF ground location. By doing so and by proper attention to known design practices for laying out microstrip circuitry, the need for blocking capacitors required by prior art arrangements is eliminated.

Millimeter wave microstrip shunt-mounted pin diode switch with particular bias means

A microwave frequency detection receiver utilizing a prescaler comprised of one or a plurality of cascaded analog frequency dividers for down-converting received microwave signals to a predetermined compressed radio frequency bandwidth, connected to a combined frequency discriminator and quantizer processor. The frequency discriminator can be either a single or multiple delay line discriminator or a two-stage feed forward digital instantaneous frequency measurement device. The receiver is characterized by wide radio frequency input bandwidth as well as accurate frequency measurement capability on short single pulse signals. Delay line discriminators can operate with high data rates and in a dense signal environment with a high probability of accurate signal frequency detection and measurement, and are thus suitable for use in electronic warfare systems.

Apparatus for measuring the frequency of microwave signals

A DC cutting circuit for passing a signal having a selected wavelength from input side circuitry to output side circuitry while cutting from said signal any DC component therein, which includes a resonator electrode having an electrical length of 1/4 wavelength and formed at a forward open end of a strip line connected to an input side circuitry, and another resonator electrode also having an electrical length of 1/4 wavelength and formed at a forward open end of a strip line connected to an output side circuitry, with said resonator electrodes being disposed in a parallel spaced relation to each other so as to couple the input side circuitry with the output side circuitry by the two resonator electrodes

DC cutting circuit

A RF crossover network includes a RF line, a DC/control line capacitively coupled to the RF line at a crossover of the RF line, and RF terminations coupled to the DC/control line. A RF signal carried on the RF line is unperturbed by the presence of a DC/control signal on the DC/control line. The RF line is mounted on a first dielectric layer including a ground plane. A second dielectric layer includes first and second surfaces with the DC/control line mounted on the first surface of the second dielectric layer and the second surface of the second dielectric layer positioned adjacent to the RF line. RF terminations are used on opposite ends of a half wave resonator. The RF terminations can comprise shunt capacitors, metal-insulator-metal (MIM) capacitors in a monolithic microwave integrated circuit (MMIC) embodiment, or open-circuited quarter wavelength transmission lines.

RF crossover network

A microwave coupling element for coupling an input conductor with an output conductor exhibiting a predetermined wave propagation resistance includes a coupling portion interposed between the input and output conductors and including two parallel strip conductors that are galvanically uncoupled from one another. The strip conductors are spaced from each other by a predetermined distance and each has a predetermined width, at least one of the predetermined width and the predetermined distance being up to twice as large as that which would correspond to a minimum mismatch with the input and output connectors. The resulting mismatch is compensated for by at least one transformation connector exhibiting a wave propagation resistance smaller than the predetermined wave propagation resistance.

Microwave coupling element

A microwave frequency divider operable in 8-16 GHZ range. A circuit resonant at a subharmonic frequency is formed by a pair of input microstrip transmission lines coupled to a pair of output microstrip transmission lines. Each input line is terminated by a varactor diode. The input signal is supplied to the resonant circuit by a pair of microstrip lines functioning as a two stage quarter wave transformer. A metal plate positioned over the resonant circuit and closely spaced from it functions to extend the upper end of the frequency range. A bias supply line for the diodes has a portion passing through a resistive foam block to remove spurious signals. A movable stub is positioned along the bias supply line to extend the lower end of the frequency range.

William D. Cornish

Papers

Broadband frequency divider