Showing papers on "Coplanar waveguide published in 1976"

Inverted Strip Dielectric Waveguide for Millimeter-Wave Integrated Circuits

Abstract: A new type of dielectric waveguide, which has a number of advantages over other previously available waveguide structures for millimeter-wave integrated circuits, is described. Dispersion characteristics and the field distributions in the waveguide are calculated using the concept of effective dielectric constant. Field distributions have been measured in the 80-GHz range in order to check the accuracy of the analytical results. This measurement has been done using a novel experimental technique, which should also be applicable to many other millimeter-wave waveguides and components.

Microwave ice detector

Abstract: A system for detecting ice on exterior surfaces of aircraft by transmitting a relatively low power microwave electromagnetic signal into a dielectric layer functioning as a surface waveguide, and monitoring the signals transmitted into and reflected from the waveguide. The waveguide includes a termination element which is mismatched with the waveguide impedance, resulting in partial or total reflection of the microwave energy from the remote end of the waveguide. As ice builds up on the surface waveguide, the impedance or reflection characteristics of the composite waveguide comprising the ice layer and the permanent surface waveguide give a reliable indication of the presence and location of the ice. The reflection characteristics are conventionally monitored utilizing a dual directional coupler and a reflectometer.

A Coplanar Waveguide with Thick Metal-Coating (Short Papers)

Abstract: A theoretical method is presented for the analysis of a coplanar waveguide, with thick metal-coating. Numerical results are given and compared with published data. It is shown that the metal-coating thickness of the coplanar waveguide causes an increase in wavelength and a decrease in characteristic impedance and that the changes are about the same as those of a slot line.

Insular waveguide directional coupler

Abstract: An insular waveguide directional coupler for use in the frequency range from about 1 GHz to about 1,000 GHz including a conductive image plane, a first length of elongated high permittivity dielectric waveguide of finite cross section adjacent to the conductive image plane, a second length of elongated high permittivity dielectric waveguide of finite cross section adjacent to the conductive image plane and spaced from the first length of waveguide to provide a coupling region therebetween, and a thin film of synthetic organic resin disposed between and secured to the conductive image plane and the lengths of waveguide, the thin film being low loss in character and having a low permittivity compared with that of the lengths of waveguide, the first length of waveguide having an inlet port at one end of the coupling region and spaced away from the second length of waveguide a distance substantially greater than the distance between the lengths of waveguide in the coupling region, the first and second lengths of waveguide having respectively first and second outlet ports at the other end of the coupling region and spaced from the other length of waveguide a distance substantially greater than the distance between the lengths of waveguide in the coupling region.

Planar balanced mixer/converter for broadband applications

Abstract: A broadband millimeter wave (26.5-40 GHz) mixer/converter utilizing slotl and coplanar strip-line for the construction of the hybrid junction. The RF and local oscillator signals are applied 180° out of phase to a pair of beam-lead diodes. A diplexer consisting of a low-pass filter and a bandpass filter is also provided to separate the IF and LO signals. A first microwave integrated circuit (MIC) card carries the waveguide to slotline transition, the slotline transmission section, the tapered coplanar waveguide section and the LO bandpass filter. A pair of Schottky-barrier diodes are connected across the transmission channels of the coplanar waveguide section to form the hybrid junction. The LO input is applied to a section of suspended strip-line on this first MIC card. A second MIC card carries the IF low-pass filter and couples to the IF output of the mixer.

Image phased and idler frequency controlled mixer formed on an integrated circuit dielectric substrate

Abstract: The tuned elements of a mixer organization are fabricated as slot-type microwave integrated circuit (MIC) elements formed by selected masking or etching of a continuous ground plane layer of conductor material on one side of an integrated circuit dielectric substrate, and of the discrete strips and other geometric forms affixed to the other side of the substrate. A pair of longitudinally aligned coplanar strip transmission line sections with an intermediate short longitudinally aligned slot transmission line section therebetween form hybrid junctions containing balanced diode modulation circuits where such coplanar lines and the slot line are joined. A strip line unit formed on the other side of the substrate is the input port for the RF input signal and is configured to provide a microstrip line-slot line transition at the midpoint of the slot line, feeding the RF input signal to both hybrid junctions with the same phase. The LO input signal is applied to the respective coplanar strip line sections with a constant phase difference therebetween of 90°. This is conveniently provided by a quadrature hybrid. The IF outputs from the coplanar lines have a 90° difference in phase and are received and summed by opposite and isolated ports of another quadrature hybrid to provide a common phase output IF signal.