Analysis of unsymmetrical broadside-coupled coplanar waveguides for microwave integrated circuits

This paper describes a design method for flip-chip monolithic millimeter-wave integrated circuits (MMICs) with a coplanar waveguide (CPW) transmission line for W-band applications. We proposed a test structure for obtaining accurate flip-chip CPW line models. We examined the transmission line characteristics of the CPW line using the test structure in the millimeter-wave range and modeled them. Using the CPW line models, we designed and fabricated both two- and three-stage amplifiers using 0.15-/spl mu/m InGaP/InGaAs high electron-mobility transistor technology. The maximum power gain of the two-stage amplifier is 12 dB at 79 GHz. The three-stage amplifier has a maximum power gain of 16 dB at 77 GHz. The agreement of measured S-parameters with calculated results demonstrates that the proposed test structure is suitable for characterizing flip-chip CPW lines and provides very accurate models.

The coplanar waveguide (CPW) gap discontinuity is an important component of many applications in the monolithic microwave integrated circuits (MMICs). Therefore, accurate modeling of the CPW gap discontinuity is very important and fundamental for the design of MMICs. In this work, a new lumped equiva1ent-circuit model which can accurately describe the characterization of the CPW gap discontinuity from 0 to 150 GHz is proposed. The parameters are extracted from electromagnetic (EM) simulations simply and conveniently without any complicated optimization algorithms. And we make the model scalable in gap length, width and space. Satisfactory fitting accuracy is obtained between the model data and EM simulations, which verifies that our model can be implemented in computer-aided design software to reduce design time and save computer resources.

The generation and characterization of both pulsed and CW high frequency waveforms using picosecond photoconductors are reviewed. A time-domain network analyzer which uses optoelectroni c techniques for on-wafer monolithic microwave and millimeter-wave integrated circuit measurements is described. An optical-microwave intermixing teclmique has been applied to phase-lock a free running microwave oscillator with picosecond laser pulses.© (1991) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

Rapid expansion of microwave systems in phased array radar and commercial applications in the emerging wireless communication system areas requires affordable, compact, lightweight, reliable, solid state, integrated microwave transmit/receive (T/R) modules. Traditional microwave modules fabricated using microstrip-based hybrid/ monolithic integrated circuitry are incompatible with low cost, high volume, robotics manufacturing techniques for multi-chip microwave modules, because of the fragile nature of current 4 mil-thick gallium arsenide monolithic microwave integrated circuits (MMICs). Backside processing, including wafer thinning and via-hole ground electrode access, are also significant yield limiting factors for MMIC manufacturing. Hughes has developed a novel, robust, flip-chip approach for microwave T/R modules using self-aligned, solder reflow, multichip assembly techniques. The rugged (25 mil thick), passivated MMIC chips with coplanar waveguide circuitry, silicon-like, on-chip multilayer metal interconnects, with off-chip plated metal electrical/thermal paths offers major advantages over conventional MMICs (Table 1). Elimination of wafer thinning will be critical for processing and handling of large-diameter wafers. The use of plated metal thermal bumps directly on top of active circuit elements leads to 30% thermal property improvement over conventional GaAs MMICs.

A front-end MIMIC (millimeter wave monolithic integrated circuit) with a 4:2 MUX/DEMUX (multiplexer / demultiplexer) functionality for 60 GHz transceiver with multiple antennas has been developed. The chip has been realized using 100 nm gatelength metamorphic InAlAs / InGaAs HEMT (high electron mobility transistor) technology on GaAs substrate together with CPW (coplanar waveguide) technology. The chip has been designed for functionality over the frequency range of 55-65 GHz. The novel topology for the MIMIC will be described. The single building blocks and details for the DPDT (double pole double throw) switch design will be explained, simulated and measured results will be compared. Finally, the overall performance for the integrated chip will be presented.

This thesis presents a specialization of the integral equation (IE) method for the analysis of three-dimensional metallic and dielectric structures embedded in laterally unbounded (open) layered media. The method remains basically spatial but makes use of extensive analytical treatment of the vertical dependence of the problem in the 2D Fourier-transformed domain. The analytical treatment restricts somewhat the class of structures that can be analyzed. Still, the field of applicability remains very large, and includes most printed circuit and integrated circuit structures. The method is developed in full numerical detail, from first principles down to the properties of new Green's functions and the computation of particular types of convolution integrals. We show how the memory and time complexity are considerably reduced when compared to the requirements of the analysis of general 3D structures. With the newly developed tool, it is possible to deal with some peculiar characteristics of microwave and millimeter-wave circuits and antennas. Most noteworthy among these is the presence of thick metallizations (either electrically, or relative to circuit features). A novel full-wave analysis of arbitrarily shaped apertures in thick metallic screens is presented. This is compared to other methods, both full-wave and approximate, and demonstrated to offer excellent accuracy. Comparison with measured data, obtained from specially constructed prototypes, further validates the new technique. A second application is to the analysis of airbridges in coplanar waveguide (CPW) and slotline (SL) circuits. Comparison of measured and simulated data validates again our technique and provides valuable information about the behavior of CPW-fed slot loop antennas. Among the more specific applications, particular attention is devoted to the analysis and design of submillimeter-wave integrated dielectric lens feeds. These were object of study in the frame of a European Space Agency project, Integrated Front-End Receivers (IFER), which our Laboratory carried out in cooperation with a team at University of Toronto. The analysis method developed in this work encompasses and extends all previous work done at our Laboratory (LEMA) related with the analysis of this kind of feed. Together with the advanced 3D ray-tracing code developed at University of Toronto, it is possible to gain a high degree of insight into the behavior of these integrated receivers.

In this work, we describe monolithic millimeter-wave integrated circuit (MMIC) Low Noise Amplifier (LNA) and mixer designs for U-Band, also known as the WR19 waveguide band (40–60 GHz). The LNAs were fabricated in NGC's 35 nm InP HEMT MMIC process. The MMICs were packaged in WR19 waveguide housings and tested for noise, both at room temperature and cryogenically. We present the results, including a comparison to the state-of-the-art, and discuss applications for amplifiers in this frequency range. To date, these are the first cryogenic 35 nm InP MMIC results covering the 40–60 GHz range. We achieved a noise temperature less than 30 K over the 40–60 GHz range, when the amplifiers were cryogenically cooled. These results are comparable with other results in the literature, and we believe are the lowest reported for MMICs in the 50–60 GHz range.

The recent research results of monolithic millimeter-wave (MMW) integrated circuits (MMICs) implemented in CMOS technology at National Taiwan University (NTU) are presented in this paper. Using standard MS/RF CMOS processes, many impressive results were demonstrated. Both the MMIC designs and measured performances will be described. Significant impacts are expected due to the development for future research works in the related areas.

A high-gain InP monolithic millimeter-wave integrated circuit (MMIC) cascode amplifier has been developed which has 8.0 dB of average gain from 75 to 100 GHz when biased for maximum bandwidth, and more than 12 dB of gain at 80 GHz at the maximum-gain bias point, representing the highest gains reported to date, obtained from MMICs at W band (75-100 GHz). Lattice-matched InGaAs-InAlAs high-electron-mobility-transistors (HEMTs) with 0.1- mu m gates were the active devices. A coplanar waveguide (CPW) was the transmission medium for this MMIC with an overall chip dimension of 600*500 mu m.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

We demonstrate a 94-GHz coplanar waveguide (CPW) to rectangular waveguide transition on high permittivity sapphire substrate. Monolithically fabricated uniplanar transition is composed of the fin-line taper and the open-type CPW to slotline transition that can be fully integrated with the flip-chip bonded monolithic microwave integrated circuits (MMICs) on single rigid sapphire substrate. From an optimized design of a low-loss single-section transition, we fabricate the back-to-back transition for the characterization. The measurements show an insertion loss of ∼1.7 dB at 94 GHz from a single-section transition, and the performance is successfully verified from a 94-GHz mixer module assembled with a flip-chip bonded MMIC mixer. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26121

We have developed V-Band (50–75 GHz) monolithic millimeter-wave integrated circuit (MMIC) low noise amplifiers using NGC's 35 nm InP HEMT technology. The MMIC LNAs exhibit noise temperatures of 150–270K over the full waveguide band. Subharmonic MMIC mixers were also developed using United Monolithic Semiconductor's GaAs Schottky diode process, and cover V-band with 15–21 dB conversion loss. These components form the front end of receivers that could be used for radio astronomy. While much of V-Band is opaque to the atmosphere, a future space probe to map the intensity of carbon monoxide (CO) in V-band would help astronomers understand the early universe.

New types of planar transmission lines employing multilayer structures are proposed for possible applications in microwave and millimeter-wave integrated circuits. Detailed investigations are presented through numerical results calculated using the spectral domain technique. The newly proposed transmission lines have many attractive features such as a large impedance range, flexibility and ability to realize complicated, densely packed integrated circuits, as well as miniaturization through the use of thin dielectric layers. Additionally, they possess all of the inherent advantages of the CPW and microstrip line. Their use in microwave circuits is exemplified through a low-pass filter realized using the new slot-coplanar lines with less than 0.5-dB insertion loss and better than 20-dB return loss. The filter's measured and calculated performances also agree well. >

A mode-matching analysis of lossy planar transmission lines is presented. This method uses a modified mode-matching technique developed for travelling-wave FET analysis. The metallic layers are treated in the same way as the remaining waveguide subregions, with each of them characterized by its complex dielectric constant. This leads to a fully self-consistent description of the conductor losses. In contrast to the usual perturbation methods, it includes metallic loss by a self-consistent description without any skin-effect approximation. The analysis holds for arbitrarily high losses and also for metallization dimensions smaller than the skin depth. The approach is validated by comparison with previous experimental and theoretical work. Monolithic microwave integrated circuit (MMIC) microstrip and coplanar lines are investigated. The variation in propagation characteristics for typical metallization thickness is studied and the consequences with regard to MMIC design are discussed. For the coplanar waveguides (CPWs) significant deviations compared to the conventional assumption of lossless zero-thickness strips are found. >

We report the design and fabrication of compact 2- and 3-stage coplanar (CPW) microwave monolithic integrated circuit (MMIC) amplifiers having high output power at Ka-band. Based on a 0.15-μm gate length GaAs PHEMT process, a two-stage MMIC driver amplifier has demonstrated at 35 GHz, a linear gain of 11 dB, an output power at 1 dB gain compression P/sub -1 dB/ of 350 mW, and a saturated output power P/sub sat/ greater than 500 mW. For the same frequency, the high-power CPW 2-stage amplifier achieved a linear gain of 9.5 dB, with P/sub -1 dB/=725 mW and more than 1 W of saturated output power, Additional thermal management resulted in an increased performance, namely, 10.4 dB linear gain, P/sub -1 dB/=950 mW and P/sub sat/=1.2 W. To our knowledge, these are the highest output powers ever reported at Ka-band for any uniplanar MMIC.

A fully integrated transceiver MIMIC (millimeter wave monolithic integrated circuit) with six antenna port functionality for 55 to 65 GHz wireless applications has been developed. The chip has been realized using 100 nm gatelength metamorphic InAlAs / InGaAs HEMT (high electron mobility transistor) technology on GaAs substrates together with CPW (coplanar waveguide) technology. The novel transceiver topology consists of switches, amplifiers, mixers, a voltage controlled oscillator and a frequency divider. The receiver chain shows noise figure < 2.6 dB on the low noise amplifier level and smaller than 7 dB including the antenna switching network. The medium output power amplifier delivers the saturated power level of + 14 dB m. This is the highest integration level for a 60 GHz compound semiconductor transceiver chip reported to-date.