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EuMA special issue on 60 GHz communication systems
Design and model studies for solid-state power amplification at 210 GHz
The high millimeter-wave (mmW) frequency range offers new possibilities for high-resolution imaging and sensing as well as for high data rate wireless communication systems. The use of power amplifiers of such systems boosts the performance in terms of operating range and/or data rate. To date, however, the design of solid-state power amplifiers at frequencies about 210 GHz suffers from limited tr
Analysis of a folded reflect-array antenna using particle swarm optimization
In this paper, a method for design and optimization of folded reflect-array antennas is proposed based on particleswarm optimization (PSO). In addition to such a powerful optimization algorithm, two further requirements have to be fulfilled. The first one is a good and fast algorithm for the exact prognosis of the far-field radiation diagram, resulting from a specific element configuration on the
About the beginnings of wireless
Many scientists and engineers contributed ? more or less successfully ? to the development of radio and wireless. This historical survey describes briefly the projects realized more than a century ago by some of them, at the early beginnings of wireless. It is hoped, in this manner, to draw attention to the unknown or forgotten researchers who built up the considerable body of knowledge that led t
Implementation of wideband digital beam forming in the E-band
This paper reports the test results of a small-scale prototype that implements a digitally beam-formed phased antenna array in the E-band. A four-channel dual-conversion receive RF module for 71?76 GHz frequency band has been developed and integrated with a linear end-fire antenna array. Wideband frequency-domain angle-of-arrival estimation and beam-forming algorithms were developed and implemente
Optical two-tone generation and SSB modulation using electro-optic modulator with suppressing redundant spectrum components
Doubled frequency optical two-tone generation and optical single sideband (SSB) modulation by the dual-electrode-type electro-optic (EO) modulator with a single Mach?Zehnder (MZ) interferometer were considered. We theoretically showed that redundant spectrum components in the modulated optical signals, which are caused by the imbalance of light splitting ratio between the two arms of the interfero
Simple method for characterizing linear multi-port microstrip structures
A simple method for the full characterization of passive n-port microwave monolithic integrated circuit (MMIC) structures using standard two-port vector network analyzer (VNA) measurements is presented. Its main advantages are: it does not require to perform measurements from all the ports of the network, no special calibration procedure is needed, the auxiliary terminations required by the proced
Design of a compact quarter wave coaxial cavity resonator for plasma ignition applications
Atmospheric and higher pressure RF and microwave plasma sources have numerous applications including material processing and spectroscopy. More recently, advantages in using such discharges for combustion ignition are being investigated. A particularly simple and compact microwave discharge generating device is the quarter wave coaxial cavity resonator (QWCCR). This paper presents a new, compacted
Compact dual-band axially corrugated profiled horn for prime-focus reflector antenna
This paper reports a new compact dual-band axially corrugated profiled horn feed (DBCPH) for prime-focus reflector antenna at C-band (uplink and downlink frequency bands with bandwidth ratio of 1.6). DBPCH consists of one sinusoid profiled section and two internal axial corrugations (internal short-circuited ring slots), for obtaining a multimode horn feed. Such a blended structure is optimized ov
Automated bench test for UHF RFID tags measurement in operational environment
This paper synthesizes protocol measurements for Ultra High Frequency (UHF) radiofrequency identification (RFID) tags? performance. We introduce the main parameters allowing the evaluation of an inlay tag performances. We characterize all devices implemented on the test bench. We explain the different programs and all methods used for the software automation. Finally, we studied the variation of t