Marc DeVincentis

Arbitrary dual-band components using composite right/left-handed transmission lines

Arbitrary dual-band microstrip components using composite right/left-handed (CRLH) transmission lines (TLs) are presented. Theory, synthesis procedure, and implementation of the dual-band quarter-wave (/spl lambda//4) CRLH TL are presented. Arbitrary dual-band operation is achieved by the frequency offset and the phase slope of the CRLH TL. The frequency ratio of the two operating frequencies can be a noninteger. The dual-band /spl lambda//4 open/short-circuit stub, dual-band branch-line coupler (BLC), and dual-band rat-race coupler (RRC) are also demonstrated. The performances of these dual-band components are demonstrated by both simulated and measured results. Insertion loss is larger than 23 dB for the shunt /spl lambda//4 CRLH TL open-circuit stub and less than 0.25 dB for the shunt /spl lambda//4 CRLH TL short-circuit stub at each passband. The dual-band BLC exhibits S/sub 21/ and S/sub 31/ larger than -4.034 dB, return losses larger than 17 dB, isolations larger than 13 dB, phase differences 90/spl deg//spl plusmn/1.5/spl deg/, and gain imbalance less than 0.5 dB at each passband. The dual-band RRC exhibits S/sub 21/ and S/sub 31/ larger than -4.126 dB, return losses larger than 12 dB, isolations larger than 30 dB, phase difference 180/spl deg//spl plusmn/4/spl deg/, and gain imbalance less than 0.2 dB at each passband.

Unoxidized porous Si as an isolation material for mixed-signal integrated circuit applications

An isolation technology for radio frequency (rf) applications based on unoxidized porous Si (PS) is demonstrated. This study examines all the important issues pertinent to incorporating PS with Si very-large-scale integration (VLSI) technology, where PS is used as a semi-insulating material. Specifically, the issues on rf isolation performance of PS as a function of porosity [from coplanar waveguide (CPW) line measurements] and PS thickness (from on-chip inductors) and the stress generated from incorporating PS regions by anodization are discussed in detail. CPW line measurements show that the relative dielectric constant of PS films decreases from 9 to 3 with increasing porosity from 24% to 78%. PS is a very low loss material with loss tangent <0.001 at 20 GHz when its porosity is above 51%. rf crosstalk through a Si substrate can be reduced to that through air by inserting a PS trench between noise generating circuit and noise sensing circuit. On-chip spiral inductors fabricated on top of PS regions of ...

A porous Si based novel isolation technology for mixed-signal integrated circuits

A novel isolation technology for RF applications based on semi-insulating porous Si (PS) is demonstrated. RF cross-talk isolation of 70 dB at 2 GHz and -45 dB at 8 GHz has been demonstrated using PS trenches that provide complete isolation between neighboring regions of a p/sup +/ Si chip. On-chip spiral inductors of 6 nH fabricated over the PS regions have been demonstrated with Q/sub max/ /spl sim/29 at 7 GHz and a resonant frequency of over 20 GHz.

Operation of the LiFi Light Emitting Plasma in Resonant Cavity

The LiFi lamp utilizes a microwave technology which directly delivers high-frequency power to a light-emitting plasma without the need for electrodes. A dielectric waveguide generates electromagnetic field modes within a resonator which efficiently couple the power to the high-temperature high-density plasma.

Longitudinally mounted light emitting plasma in a dielectric resonator

Methods for coupling power from a dielectric resonator to a light-emitting plasma have been previously described (Gilliard et al IEEE Trans. Plasma Sci. at press). Inevitably, regardless of the efficiency of power transfer, much of the emitted light is absorbed in the resonator itself which physically surrounds much if not all of the radiating material. An investigation into a method is presented here for efficiently coupling power to a longitudinally mounted plasma vessel which is mounted on the surface of the dielectric material of the resonator, thereby eliminating significant absorption of light within the resonator structure. The topology of the resonator and its physical properties as well as those of the metal halide plasma are presented. Results of basic models of the field configuration and plasma are shown as well as a configuration suitable as a practical light source.

A 40 GHz communication link with IF-assisted self-heterodyne direct down conversion

A 40 GHz communication link was demonstrated using a combination of super-heterodyne mixing and self-heterodyne direct down conversion. The broadcast carrier and modulated signals inherent in self-heterodyne transmission were first mixed down from 40 GHz to an IF of 1.5 GHz using a 10.375 GHz LO and a novel, low LO power 4/sup th/ harmonic diode mixer. These IF signals passed through an amplifier chain with a total gain of G=75 dB and noise figure of NF=1.21 dB prior to direct down conversion with a self-mixer. It was shown analytically and experimentally that the phase noise cancellation inherent in self-heterodyne detection is preserved independent of the phase noise of the additional LO signal. The input and output IF signals had the same phase noise up to 100 kHz carrier offset for a transmission distance of 2 meters.

Increased collection efficiency of LIFI high intensity electrodeless light source

Recently, RF driven electrodeless high intensity light sources have been implemented successfully in the projection display systems for HDTV and videowall applications. This paper presents advances made in the RF waveguide and electric field concentrator structures with the purpose of reducing effective arc size and increasing light collection. In addition, new optical designs are described that further improve system efficiency. The results of this work demonstrate that projection system light throughput is increased relative to previous implementations and performance is optimized for home theater and other front projector applications that maintain multi-year lifetime without re-lamping, complete spectral range, fast start times and high levels of dynamic contrast due to dimming flexibility in the light source system.

Combining electromagnetics with solid state devices

Professor Hartwig Thim has led a distinguished career in the field of high-frequency solid state devices. In this paper we present a tribute to his work by highlighting the philosophy of analysis shared by Professor Thim, and by all great researchers.ZusammenfassungProfessor Hartwig Thim hat eine bemerkenswerte Karriere auf dem Gebiet der Hochfrequenz-Festkörperelemente hinter sich. In diesem Artikel zollen die Autoren seiner Arbeit Tribut, indem sie die Philosophie der Analyse, die von Professor Thim und von allen großen Forschern geteilt wird, hervorheben.

A compact bandpass filter using a 1-D periodic slow wave structure

A compact, dual-mode bandpass filter based on a stripline ring resonator is presented. This 2-pole filter was implemented using a one-dimensional periodic structure, such that the physical length of the ring resonator was decreased due to the slow wave effect. At a center frequency of 2 GHz, the length of the ring was reduced by 41.8%, and the overall footprint of the filter was reduced by 51.9%. With the periodic structure, this filter achieved 0.6 dB of loss centered in a 310 MHz bandwidth, compared to 1 dB of loss centered in a 230 MHz bandwidth achieved without the slow wave structure.

A Multilayer Integration Technique for Low-loss, Low-crosstalk Interconnects and Circuits for RF Silicon MMICs

This paper reports our latest progress in developing the Silicon/Metal/Polyimide (SIMPOL) architecture for high-performance RF interconnects. This 3D MMIC process utilizes polyimide for an interlayer dielectric on low-resistivity CMOS-grade silicon substrates. The SIMPOL structure exhibits low noise-crosstalk (<¿80dB up to 18GHz and <¿40dB up to 50GHz) along with excellent insertion loss (<¿0.25dB/mm up to 45GHz). A branch line coupler was implemented and a bandpass filter was designed at 37 GHz using the SIMPOL process. The results demonstrate the multilayer capability, superior performance, and applicability of SIMPOL to advanced millimeter-wave wireless communication systems.