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MRF volume 2 issue 6 Cover and Back matter
Noise properties of balanced amplifier configurations
This paper analyzes the noise properties of balanced amplifier configurations in terms of noise waves and discusses the effect of various amplifier configurations on the noise and signal parameters. It shows how the noise generated in the load on the input coupler of a balanced amplifier deteriorates the amplifiers noise resistance parameter with respect to that of its component amplifiers. The pr
A voltage-mode class-S power amplifier for the 450 MHz band
This paper reports on a novel voltage-mode class-S power amplifier for the 450 MHz band, based on GaN?HEMT monolithic microwave integrated circuits (MMICs). It achieves a peak output power of 3.4 W for a single tone at 400 MHz, encoded in standard band-pass delta-sigma modulation with 1.6 Gbps sampling frequency. The corresponding efficiency is 38%, peaking at 52% for 0.5 W output power. In order
Low-cost analog fiber optic links for in-house distribution of millimeter-wave signals
In this article, analog fiber optic links (radio-over-fiber, RoF, links) are presented as a flexible, low-cost solution for in-house distribution of millimeter-wave (mmw) signals. Mode-locked laser diodes (MLLD) serve as inexpensive mmw sources for the downlink distribution of mmw signals across an optical fiber link. We compare the robustness of direct and external RF modulation for such MLLD-bas
Semi-physical nonlinear circuit model with device/physical parameters for HEMTs
A nonlinear circuit model (NCM) with physical parameters is proposed for direct simulation of the RF characteristics of GaN high-electron-mobility transistors (GaN HEMTs) on the basis of device structure. The physical equations are used for the construction of the model in order to connect strongly the model parameters with the device/physical parameters. Hyperbolic tangent functions are used as t
Design of a very low-power, low-cost 60 GHz receiver front-end implemented in 65 nm CMOS technology
The research on the design of receiver front-ends for very high data-rate communication in the 60 GHz band in nanoscale Complementary Metal Oxide Semiconductor (CMOS) technologies is going on for some time now. Although a multitude of 60 GHz front-ends have been published in recent years, they are not consequently optimized for low power consumption. Thus, these front-ends dissipate too much power
A dual wideband Sierpinski carpet fractal-shaped planar monopole antenna with CPW feed
A dual wideband design of Sierpinski carpet fractal-shaped planar monopole antenna with a coplanar waveguide (CPW) feed is proposed in this letter. Wide impedance bandwidth of 22% at lower resonance from 4.88 to 6.08 GHz and 41.7% at higher one, which ranges from 9.5 to 14.5 GHz, is obtained. Measured realized antenna gain is around 5 dBi at the lower band centered around 5.5 GHz and are around 4.
Polymer-based micromachined rectangular coaxial filters for millimeter-wave applications
In this paper, micromachined devices for millimeter-wave applications at U- and V-bands are presented. These structures are designed using a rectangular coaxial line built of gold-coated SU-8 photoresist layers, where the coaxial center conductor is suspended in air by stubs. The designs include a stepped coplanar waveguide (CPW)-to-coaxial transition at 63 GHz, with an insertion loss of 0.39 dB a
Physical layer design, link budget analysis, and digital baseband implementation for 60 GHz short-range applications
The large bandwidth of the 60 GHz frequency band enables wireless short-range applications with data rates of several Gbit/s. The German project EASY-A has focused on early prototype implementations for selected applications, although no generally accepted 60 GHz standard has been available at the time. The implementations are based on application-oriented physical layer designs and link-budget in
60 GHz short-range communications: channel measurements, analysis, and modeling
This article presents measurement and analysis results for 60 GHz short-range wideband radio channels. We consider two scenarios, referred to as ?very-high-rate extended-range? (VHR-E) and ?ultra-high-rate cordless? (UHR-C). The VHR-E measurements aimed at 60 GHz fixed networks for an Airbus A340 cabin both under static and dynamic (shadowing due to passenger movement) channel conditions. We descr