A waveguide assembly comprising at least two waveguide components. The waveguide assembly comprising a first waveguide portion and a second waveguide portion each comprising an interior surface and an exterior surface. The interior surface of the first waveguide portion defining a first portion of a first microwave component and a first portion of a second microwave component. The interior surface of the second waveguide portion defining a second portion of the first microwave component and a second portion of the second microwave component. The first waveguide portion and the second waveguide portion being adapted for being coupled together to form the waveguide assembly such that, when coupled together, the waveguide assembly comprises at least the first microwave component and the second microwave component.

multi-component waveguide assembly

This paper describes the NRD guide (nonradiative dielectric waveguide) proposed as a new type of dielectric transmission line for millimeter-wave integrated circuits. After the operation principle and the modes of the NRD guide are explained briefly, the nonradiative and low-loss nature of practical importance are confirmed experimentally. Next, the behavior of the transmitted wave in a bend is studied. Configurations and characteristics of typical NRD guide circuit elements, such as a matched terminator, a directional coupler, a circulator, a beam lead diode mount and a Gunn diode oscillator also are discussed. Using these circuit elements, a transmitter and a receiver are fabricated at 35 GHz and their performances are evaluated. The dimensions of the transmitter and the receiver are as compact as 68 mm × 66 mm and 85 mm × 75 mm in area, respectively. The output power of the transmitter is 10 mW and the temperature coefficient of the frequency is 0.57 ppm/°C. The temperature coefficient of the receiver also is as small as −0.76 ppm/°C. The noise figure is measured to be 10.6 dB. This value is obtained by using Si diodes in the mixer. Finally, as particular applications of the NRD guide, a filter, a power divider, and a leaky-wave antenna are described.

Millimeter‐wave integrated circuits using nonradiative dielectric waveguide

Transmitter and receiver front ends have been fabricated in an integrated manner at 35 GHz, using a nonradiative dielectric waveguide (NRD guide). The structure and characteristics of various key components are described. Transmission testing over a ten-month period using the front ends has shown that the NRD guide integrated circuits are reliable in performance, moderate in size, and hence promising at millimeter wavelengths. >

Millimeter-wave transmitter and receiver using the nonradiative dielectric waveguide

This paper presents a new microwave device - a non-radiative dielectric (NRD) waveguide with a dielectric pseudochiral /spl Omega/-slab - the /spl Omega/-NRD waveguide. A rigorous full-wave analysis is presented and the modal equations for the longitudinal-section magnetic (LSM) and longitudinal-section electric (LSE) modes are derived. The dispersion curves and operational diagrams for the first hybrid LSM modes are presented. The effect of the pseudochiral /spl Omega/-medium is discussed. New interesting modal features are revealed, showing that the propagation characteristics may differ considerably from the common isotropic case.

Full-wave analysis of a nonradiative dielectric waveguide with a pseudochiral /spl Omega/-slab

A V-band n-type indium antimonide (InSb) junction circulator supported in a three-port finline structure has been fabricated and measured. Broad-band operation for a semiconductor junction circulator over the frequency range 50-75 GHz at a temperature of 77 K has been demonstrated for the first time. With an applied magnetic flux density of 0.88 T, approximately 10 dB of differential isolation has been measured over the entire waveguide frequency band. The measured results also indicate that circulation is possible when the semiconductor material has /spl epsiv//sub eff/ 0, but the bandwidths of the circulators measured are restricted by the cutoff frequency of the V-band waveguide. Experimental evidence also showed that a disc or triangular-shaped semiconductor suspended in an E-plane junction without the finline circuit provides circulation. The experimental results clearly illustrate the broad-band behavior of semiconductor junction circulators for operation beyond 40 GHz, which is difficult to achieve with ferrite-based circulators.

Measurements of V-band n-type InSb junction circulators

A technique is described for constructing a high-performance nonradiative dielectric waveguide (NRD guide) circulator for use at 50 GHz. A mode suppressor, which serves to reduce unwanted modes to a negligible level, was devised and used to improve circulator performance significantly. A half-wavelength step transformer was installed at each port of the circulator to increase the operational bandwidth. The insertion loss of this circulator is less than 0.3 dB, and the 20-dB isolation bandwidth is about 2.6 GHz. Characteristics of the NRD guide circulator are analyzed based on an equivalent circuit representation. This analysis considerably facilitates the design procedure of the circulator. >

T. Yoheyama

Papers

Design and fabrication of a nonradiative dielectric waveguide circulator