Showing papers on "Coplanar waveguide published in 1982"

Analysis of conductor-backed coplanar waveguide

Abstract: The transmission properties of a coplanar waveguide printed on conductor-backed substrates are analysed using the spectral-domain technique. For a fixed substrate thickness, the characteristic impedance and the phase constant may be varied independently by simply adjusting the widths of the centre strip and the slots in the transmission line.

Losses in Coplanar Waveguides

Abstract: Conductor losses in coplanar waveguides have been calculated using a quasi-static Green's function approach. These calculations and others on dielectric and radiation losses are used to compute the quality factor of half-wavelength resonators, and comparison with measurements show good agreement.

Slotted antenna array excited by a coplanar waveguide

Abstract: The letter gives a new concept of exciting slotted antenna arrays. There both the slots and the feeder are etched on the same side of the printed circuit board. A channel is cut perpendicular to the slots and a coplanar waveguide for exciting the slots is inserted into the channel. The concept has been experimentally verified on a model.

Analysis of slow-wave phenomena in coplanar waveguide on a semiconductor substrate

Abstract: Slow-wave characteristics of a coplanar waveguide with substrate resistivity are analysed using the mode-matching technique. This waveguide is suitable for microwave monolithic integrated circuits because of its coplanar configuration. Numerical results are presented and compared with an experimental measurement in the literature.

Circuit matching elements

Abstract: The invention provides circuit matching elements pri­ marily for integrated circuits and particularly for monolithic microwave integrated circuits. A transmission line in accordance with the invention is provided with a thin metallic film deposition disposed in the signal propagation path. The effect of the film is to increase the specific capacitance of the line without decreasing the specific inductance. The result is a slowing down and therefore a decrease of the wavelength of signals in the line. An example of an implementation of the invention is a coplanar waveguide having a central thick conducting line element (32) and outer thick conducting line elements (28, 30) mounted on a substrate (21). The central element overlies a thin metallic film (22) which also underlies the outer conducting line elements and is insulated from the latter by polyimide insulation (24, 26).

Full-wave analysis of integrated transmission lines on layered lossy media

Abstract: Cohn's method of analysis of the slot line on a dielectric substrate is extended to the case of integrated lines on a lossy inhomogeneous substrate. The slow-wave characteristics of the metal-insulator-semiconductor coplanar waveguide for MMIC applications are calculated and found to be in good agreement with the experiments.

Quasi-Static Characteristics of Coplanar Waveguide on a Sapphire Substrate with its Optical Axis Inclined

Abstract: A variational expression is presented for the line capacitance of a coplanar waveguide on a single-crystal sapphire substrate with a tilted optical axis. Numerical results are obtained by means of the Ritz procedure.

Broadband planar coplanar waveguide-slotline transition

Abstract: A planar two-stub coplanar waveguide-slotline transition is analysed using equivalent circuit approach and is designed by optimizing the slotline and the stub lengths. The end reactances for the two stubs are evaluated and cancelled separately under maximum power transfer conditions. Experimental VSWRs less than 1.12 in the band 3.2 - 4.4 GHz are measured associated with an insertion loss of 0.6 dB.

Coplanar waveguide quadrature hybrid having symmetrical coupling conductors for eliminating spurious modes

Abstract: A coplanar waveguide quadrature hybrid is herein disclosed which produces even E-field symmetry about the center line of transmission during both even-and odd-mode excitation. In a first embodiment of the present invention, a first coupling element of a generally elongated shape is bifurcated and is interconnected at its ends to form a first rectangular coupling element. A second rectangular coupling element is disposed within the first rectangular coupling element. In a second embodiment of the present invention, one of the short sides of a first rectangular coupling element is broken and is cross-coupled to a third rectangular coupling element similar to the second rectangular coupling element, the third rectangular coupling element being disposed within a fourth rectangular coupling element similar to the first coupling element. The fourth rectangular coupling element is then directly connected to the second rectangular element to form a composite coupling element. During odd-mode excitation, the resulting CPW structures do not create an E-field between the ground planes and thus eliminate the spurious "slot-line" mode of operation of prior art CPW devices.

Dielectric waveguide; a low-cost technology for millimetre wave integrated circuits

Abstract: This paper describes the characteristics of two types of dielectric waveguide, the so-called insular and image guide configurations. The relevance of this technology to millimetre-wave integrated circuits is demonstrated and the design and performance of a number of dielectric waveguide components is described.A thick-film printing method for the mass production of dielectric waveguide circuits is also described and the feasibility of using this technique for the production of complete millimetre-wave integrated circuits is demonstrated.

GaAs Monolithic Circuits Mounted Over High Q Dielectric Resonators

Abstract: The coupling of a dielectric resonator through coplanar waveguides is experimentally studied and the feasibility of very selective microwave circuits, where the resonator is placed below the active and passive circuit components, is demonstrated. The design and the operation of high-stability feedback-type coplanar oscillators are reported. The possibility of mounting a monolithic chip over a high-Q dielectric cavity, avoiding unwanted resonator coupling anywhere in the circuit, is demonstrated. This allows the sealing of the overall circuit in a practical low-size case. Finally, the performances of a test monolithic chip carrying two different oscillators are stressed.

Symmetrical coupled line coplanar waveguide filter

Abstract: A coplanar waveguide filter is disclosed including a pair of grounded conductors (36) disposed on a surface (34) of a dielectric substrate equidistant from a transmission center line (42), and first (30) and second (32) conductors on said substrate surface (34) between said grounded conductors (36) and symmetrically disposed with respect to the transmission center line (42) by virtue of one conductor (32) being bifurcated, and the other not. The structure produces coupled sections of coplanar waveguide transmission lines which are both physically and electrically symmetrical. Solutions for the even and odd-mode impedance are given, allowing synthesis of a wide range of filter functions.

Printed Slotted Array Excited by a Coplanar Waveguide

Abstract: This paper describes a new concept of exciting slotted arrays. A coplanar waveguide printed on the same side as the slots serves as a feeder conductor. Two models of printed arrays with the antiresonant slots excited in this manner were realized.

Composite optical waveguide

Abstract: PURPOSE:To obtain functions which take advantage of a plannar type waveguide and a channel type waveguide without providing a lens, etc., specially by composing an optical waveguide of plural kinds of waveguides in combination and incorporating at least one kind of waveguide in other waveguides. CONSTITUTION:A composite optical waveguide is equipped with a plannar type waveguide 2 constituted on a substrate 1 of glass, etc., a semiplannar type waveguide 3 constituted as included in the plannar type waveguide 2, and a channel type waveguide 4 included in the waveguide 3. The waveguide 2 is formed of, for example, Li2NbO3, etc., and the waveguides 3 and 4 are formed with large refractive indexes by diffusing titanium, etc., thermally into prescribed areas in the waveguide 2. The waveguide 4 is parallel and tapered in the waveguide 3; a light signal is entered as shown by an arrow to spread into the waveguide 3 from a cut part 4', and then passed through a convex lens to have arcuate section 3', so that it is transmitted into the waveguide 2 as a wide flat beam.

Dielectric and conductor losses in coplanar waveguides

Abstract: Conductor and dielectric losses in a coplanar waveguide are analyzed and the results are verified experimentally. Since the waveguide is made of two conductors, TEM transmission is assumed and the Laplace equation for the potential distribution in the waveguide cross section is solved. From the resultant potential distributions, the current distributions on the conductor surfaces and the conductor loss are obtained. We also obtain the effective dielectric constant, which expresses the electrical effect exerted on the waveguide by the dielectric substrate. From this quantity, the dielectric loss is derived. The Laplace equation is solved numerically on a computer using the successive overrelaxation method. Only one quarter of the cross section is analyzed due to symmetry, so that computation time and memory requirements are reduced. The experiment verification of these results involves measurement of Q of a resonator consisting of a coplanar waveguide. The difference between the theoretical and experimental values is less than 25% for the conductor loss and less than 6% for the dielectric loss.

Propagation and conversion of light waves in graded-index planar waveguides

Abstract: The concept of zigzag propagation of light rays in a dielectric waveguide is used to show how to determine the coefficient of attenuation of light representing its escape from the waveguide and the coupling constant of interacting waves in a periodically corrugated waveguide. It is also shown that this concept makes it possible to provide a simple explanation of some of the observations made earlier in relation to integrated optics.

Slow-Wave Approach for Monolithic Ga-As ICs

Abstract: One of the most important things in the MMICs design is to minimize the monolithic circuit size. Microstrip or coplanar line approach, cannot lead to a consistent size reduction because the physical line lengths, for a given electrical length, are not very different in A1/sub 2/0/sub 3/ and in GaAs.

A 22 to 24 Ghz Cryogenically Cooled Low Noise FET Amplifier in Coplanar Waveguide

Abstract: This paper describes the design and development of a 22 to 24 GHz Cryogenically Cooled Amplifier with a noise temperature of 150K and a gain of 33 dB at 23 GHz when the amplifier is cooled to 77K.

Slow-Wave and Coplanar Monolithic GaAs Circuits

Abstract: The major results of a study aimed at reducing the monolithic microwave circuit size are presented. The paper first reports the design and performances of new low-coupling coplanar circuits, which are suitable for both monolithic and hybrid applications and show a very flat coupling and a high directivity over a broad frequency range (e.g., 5 + 13 GHz). Then, experimental results and design data are presented for new low-size slow-wave couplers. Finally, the practical use of the slow-wave approach for overcoming some well known problems in the monolithic circuit design is described and the performances of a two-stage medium power monolithic amplifier, using a slow-wave line length in the interstage matching network, are stressed.