Microwave Modules Research Articles

Low-Loss and Wideband Package Transitions for Microwave and Millimeter-Wave MCMs

This paper presents high-performance flip-chip, through-substrate via and board-level BGA transition designs applicable in microwave and millimeter-wave multichip module (MCM) assemblies. Full-wave electromagnetic analysis was performed to achieve optimized transition structures. Interconnection test structures were fabricated in ceramic substrates and their performance was validated using on-wafer scattering parameter measurements. Both the flip-chip transition and the through-substrate via transition with a height of 800 mum exhibited return losses better than 25 dB and 20 dB, respectively, with low transmission losses up to 50 GHz. Furthermore, the wideband board-level BGA transition with a standoff height of 500 showed low insertion loss (< 0.5 dB) over a wide frequency range, from direct current (dc) up to 32.5 GHz.

Dual-Polarized Broadband Array Antenna With BOR-Elements, Mechanical Design and Measurements

A dual polarized broadband phased array antenna designed for the frequency range 6-18 GHz, a 45deg conical grating lobe free scan volume and equipped with BOR-elements developed by Saab is presented. The aim with this array element is to bring about a dual polarized broadband array antenna that is easy to assemble, disassemble and connect to active microwave modules. Disassembling may be important for maintenance and upgrade reasons. Mechanical design and electromagnetic performance in the form of active reflection coefficient, calculated from measured mutual coupling coefficients, and measured active gain element pattern for a central and an edge element is presented. Edge effects in the array, which may be severe in small broadband arrays, are considered in this paper

A transmission-line microwave interferometer for plasma electron density measurement

We present both the theoretical analysis and proof-of-principle experimental results of a novel transmission-line microwave interferometer for measurements of plasma electron density. The principle of this technique is the same as conventional microwave interferometers except that the sensing microwave propagates along a transmission-line structure. For this study, the transmission-line is a circular coaxial dielectric waveguide operated at 2.4 GHz. A microwave module consisting of a microwave source and a phase detector has also been developed for detecting the phase of the microwave propagating through the transmission-line. Good agreement of phase measurements between the microwave module and a microwave network analyser has been demonstrated. The electron density measured by the interferometer is also consistent with the results from a Langmuir probe.

Polyharmonic distortion modeling

For more than a quarter of a century, microwave engineers have had the benefit of a foundation of mutually interacting components of measurement, modeling, and simulation to design and test linear components and systems. S-parameters are perhaps the most successful behavioral models ever. They have the powerful property that the S-parameters of individual components are sufficient to determine the S-parameters of any combination of those components. S-parameters of a component are sufficient to predict its response to any signal, provided only that the signal is of sufficiently small amplitude. We have presented the PHD modeling approach. It is a black-box frequency-domain model that provides a foundation for measurement, modeling, and simulation of driven nonlinear systems. The PHD model is very accurate for a wide variety of nonlinear characteristics, including compression, AM-PM, harmonics, load-pull, and time-domain waveforms. The PHD model faithfully represents driven nonlinear systems with mismatches at both the fundamental and harmonics. This enables the accurate simulation of distortion through cascaded chains of nonlinear components, thus providing key new design verification capabilities for RF and microwave modules and subsystems

High performance cryogenic packaging for microwave applications of high temperature superconductors

For microwave applications employing high temperature superconductor (HTS) technology to be commercially viable, a high performance cryogenic package is essential. Design considerations to minimise the heat leaks from ambient through conduction along the electrical interconnects and through radiation from the package walls, to reduce the size and mass and to reconcile the physical characteristics of the wide range of materials used within the microwave module and cryogenic package are discussed. Fabrication, process and assembly techniques, which play an important role in determining the long-term reliability of any HTS system, are described. Two examples of the design of cryogenic packages, for commercial and military applications, with inherent mechanical and thermal integrity, high reliability and which do not require a regular maintenance regime are presented to illustrate the design techniques being developed.

Generating and evaluating designs and plans for microwave modules

This paper describes the process planning techniques we developed for use in an Integrated Product and Process Design (IPPD) tool for the design and manufacture of microwave transmit/receive modules. Given a collection of data about the design of a microwave module, the IPPD tool uses a combination of AI planning and OR trade-off analysis to produce a collection of alternative designs and alternative process plans that have Pareto optimal values for manufacturing and purchasing lead time, process yield, cost, and number of suppliers. The IPPD tool provides facilities to enable the user to generate and examine these Pareto optimal alternatives in real time, in order to provide immediate feedback on how to modify the design to improve its cost and productivity.

Higher yields and reliability with automated assembly of microwave modules

Microwave modules and hybrid circuits have some unique requirements that demand extremely precise dispensing and placement, delicate handling and well controlled curing (or reflow). Assembly of these products can be challenging and defects may result in labor‐intensive manual assembly methods. A better way is to apply automated manufacturing techniques to the assembly of microwave modules and hybrid circuits and thereby eliminate many of the variables that may narrow the process window.

A generative approach for concurrent manufacturability evaluation and subcontractor selection

Abstract This paper describes a general approach for performing manufacturability evaluation and subcontractor selection concurrently. The approach evaluates the manufacturability of a proposed design with respect to the capabilities of candidate partners and allows a product development team to select those partners that best fit the design's manufacturing requirements. Integrating manufacturability evaluation and partner selection provides vital design feedback at a point when modifications to improve the fit between the design and the partners are less costly and less disruptive. The paper describes the application of this approach to a class of flat mechanical products and microwave modules.

Manufacturability analysis a useful subset of systems engineering

The application of manufacturability analysis to the design of mechanical parts in electronic systems improves quality, performance and reliability. Typical interest areas include equipment enclosures, transducers and high-tech microwave modules. New performance levels are feasible due to improved surface quality, stability, reduction of seam widths or the use of sophisticated materials. The stepwise procedure points out attractive solutions for challenging airborne, maritime or space sensor platform environments. A thorough understanding of manufacturability judgement and knowledge about current milling, welding and coating processes is essential as well as the earliest application of the formulated principle.

Integrated product and process designenvironment tool for manufacturing T/R modules

We present a decision-making assistant tool for an integrated product and process design environment for manufacturing applications. Specifically, we target microwave modules that use electro-mechanical components and require optimal solutions to reduce cost, improve quality, and gain leverage in time to market the product. This tool will assist the product and process designer to improve their productivity and enable them to cooperate and coordinate their designs through a common design interface. We consider a multiobjective optimization model that determines components and processes for a given conceptual design for microwave modules. This model outputs a set of solutions that the Pareto optimal concerning cost, quality, and other metrics. In addition, we identify system integration issues for manufacturing applications, and propose an architecture that will serve as a building block to our continuing research in virtual manufacturing applications.

A slab-shaped electron cyclotron resonance ion beam source for in-line running target treatments

The possibility of industrial surface treatments of broad metallic rolls by appropriate ion beams has motivated our study of an immersed electron cyclotron resonance slab-shaped ion source composed of a number of elementary microwave modules fed in parallel through a linear power divider. We describe the performances of a single module implemented by a 45-mm-height ionization chamber of 80×15 mm cross section surrounded by a set of permanent magnets in a multipole configuration. A current density of 5 mA/cm2, uniform to within 10% over a 60 mm width, has been obtained for argon as well as for oxygen and nitrogen under a 500 W input power and a gas pressure of 5–8×10−3 mbar in the ionization chamber. Moreover, we have investigated the case of the non-normal incidence of the ion beam onto the running target. For 30° and 60° incidence angles with respect to the normal, the current density loss is 15% and 25%, respectively.

A new instrument and technique for diagnosing electromagnetic design problems in microwave module housings and component packages

A method of measuring the frequencies at which resonances occur and the distribution of the associated electric field intensity at the inside face of the housing or package lid has been developed and tested. The method does not require modification of the connections to the microwave assembly within the housing. It is only necessary that the housing or package have a flat lid and that it be left off so that the item under test can be mounted on an equivalent flat plate on the test instrument. The microwave assembly in the housing or package may be operated normally while resonant field distributions are being measured. The prototype instrument yields results that demonstrate the practical application of this measurement assembly as a diagnostic and design development tool for microwave housings and packages of rectangular metal box basic shape. Resonances in the 8-12 GHz range have been accurately measured and indicate that by scaling dimensions an assembly for use at millimeter wavelengths is feasible.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Computer‐aided manufacturing of advanced microwave modules

AbstractThe application of computer‐aided manufacturing (CAM) techniques to the assembly and test of a low‐cost, high‐volume X‐band Radar T/R module will be investigated by highlighting the differences between low frequency and microwave CAM methods, focusing on the difficulties of automated testing, evaluation, and circuit tuning. The problems encountered when implementing high‐precision automated assembly and test methods, which include wire‐bonding, soldering, piece‐part placement, thin wafer GaAs probing, and a novel implementation of a microwave circuit laser‐tuning technique will also be discussed. These CAM techniques, combined with integrated MMIC technology, are then used to illustrate a manufacturing philosophy targeted toward high‐volume microwave module production.

Automated Test Equipment for Phased-Array Modules

A computer-controlled production test system for air-borne phased-array microwave modules is described. In the transmit mode accurate measurements of module output power and phase as a function of input power and frequency are made automatically on a pulse basis, and with 4:1 frequency translation from module input to output. Module receiver gain, IF output phase, and noise figure are measured as a function of frequency and local oscillator input power in the receive mode. Other measurements under computer control include dc levels, input and output VSWRS, gain compression, output pulse characteristics, spurious levels, and spectral purity. All test parameters are automatically compared to unit-specification limits as well as reference-standard (unit-to-unit) limits. The system errors are measured periodically through use of calibration standards, stored in memory, and applied as corrections to the measured data on the module under test. Input power, derived from a coherent microwave synthesizer, is automatically adjusted to the required level prior to each test. All test data are recorded on magnetic tape and available to the operator by means of a line printer when desired. The module test fixture incorporates precision (APC)-7 to module adapters, dc connections, an array simulator, and temperature control.

Ferrimagnetic Parts for Microwave Integrated Circuits

Tremendous technological strides have been made in recent years in the development of miniaturized microwave components and modules using microstrip transmission lines in combination with both semiconductor and ferrite technology. This technology growth has been spurred by rapidly increasing microwave systems complexity and diversity and the need for lower cost, more reliable, and smaller microwave assemblies. This paper describes the design and performance of various ferrimagnetic components as functional blocks for use in microwave integrated modules. The design and performance of the following components are described as well as their utilization in various multifunction modules: junction circulators both fixed bias and latching including their use as isolators, duplexers, switches, modulators, and other signal processing circuits; ferrimagnetic planar phase shifters; various combinations of these circuit elements where both all ferrimagnetic and composite ferrimagnetic/dielectric substrates are utilized.

Integrated microwave modules—a prospectus : W. M. Webster, IEEE Trans.ED-15, July (1968), p. 446

Integrated microwave modules—a prospectus : W. M. Webster, IEEE Trans.ED-15, July (1968), p. 446