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MRF volume 5 issue 2 Cover and Back matter
MRF volume 5 issue 2 Cover and Front matter
A 2-bit, 3.1 GS/s, band-pass DSM receiver for active antenna systems
This paper presents a radio frequency (RF) continuous-time band-pass delta sigma modulator (CT BP DSM) receiver realized in a 180 nm SiGe BiCMOS technology. It also provides an introduction to active antenna systems (AAS) for cellular infrastructure base stations, which is the target application for this RF integrated circuit (IC). The internal quantizer and feedback digital to analog converter (D
Multi-channel reconfigurable front-end architecture for waveform-agile radar
This paper presents the design of a multi-channel reconfigurable front-end architecture for a waveform-agile radar. At first the purpose of the design is explained following the status of research on software-defined radar at MTSR. A description of the proposed system architecture is given with details on sub-systems implementation. Then some preliminary results obtained on a prototype of the plat
Enhanced tunable performance of high -factor BaSrTiO film bulk acoustic wave resonators
Emerging intrinsically tunable film bulk acoustic wave(BAW) resonators allow the development of new generation reconfigurable and agile microwave circuits. In this paper, we demonstrate the enhancement of tunable performance of the high Q-factor BaSrTiO BAW ? solidly mounted resonators (BAW?SMR) by varying Ba concentration. The BaSrTiO BAW?SMR reveal tunability of series resonance frequency up to
Position estimation of lap joints for seam tracking applications at mm-wave frequencies
In this paper, we present the results of using a frequency-stepped continuous-wave radar system to estimate the position of overlapping and electrically good conductive plates. We especially focus on polarimetric scattering effects caused by the step of a lap joint, which is a common welding-geometry. To model the step's contribution to the overall scattered signal, we use a two-dimensional combin
Miniature single-sideband subharmonically-pumped 60 GHz direct upconverter in a uniplanar GaAs pHEMT technology using inductive and capacitive loading techniques
This paper presents a novel, compact, single-sideband (SSB) subharmonically-pumped (SHP) direct upconverter developed in a uniplanar 0.18 ?m GaAs technology. A total of 100 MHz in-phase and quadrature signals directly modulate the second harmonic of a 30 GHz carrier signal, producing a 60.1 GHz output. Two pairs of antiparallel diodes reduce feed-through of the 30 GHz local oscillator (LO) signal
Toward highly scaled AlN/GaN-on-Silicon devices for millimeter wave applications
In this work, the possibility of achieving GaN-on-Si devices for millimeter wave applications operating at high bias is demonstrated. It is shown that highly scaled AlN/GaN-on-Si double heterostructure enables us to significantly improve electron confinement under high electric field as compared to single heterostructure while delivering high carrier density (>2 × 10 cm). Subsequently, trapping ef
Study of the noise processes in microwave oscillators based on passive optical resonators
Two types of optoelectronic oscillators delivering high spectral purity microwave signals are presented in this paper. These oscillators use the Pound?Drever?Hall laser stabilization technique to lock the laser carrier onto two different types of passive optical resonators featuring high-quality factors: a fiber ring resonator (FRR) and a whispering gallery mode monocrystalline disk-shaped micro-r
Human motion classification using a particle filter approach: multiple model particle filtering applied to the micro-Doppler spectrum
In this article, a novel motion model-based particle filter implementation is proposed to classify human motion and to estimate key state variables, such as motion type, i.e. running or walking, and the subject's height. Micro-Doppler spectrum is used as the observable information. The system and measurement models of human movements are built using three parameters (relative torso velocity, heigh