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Optically modulated III?V nitride-based high-power IMPact Avalanche Transit Time oscillator at Millimeter-wave window frequency
Extensive simulation experiments are carried out for the first time, to study the optical modulation of the high- frequency characteristics of III?V GaN-(gallium nitride) based top-mounted and flip-chip IMPact Avalanche Transit Time (IMPATT) oscillators at MM-wave window frequency (140.0 GHz). It is found that the un-illuminated GaN IMPATT is capable of delivering a RF power of 5.6 W with an effic
On-chip spiral inductor in flip-chip technology
Performance comparison is made between on-chip spiral inductor in flip-chip versus wirebond package technology. Full-wave electromagnetic simulation and on-strip measurement techniques were used to study the performance fluctuations of inductor within flip-chip environment. Results show that the performance of a flipped silicon-based spiral inductor is affected by the radio frequency (RF) current
Blocker filtering low-noise amplifier for SAW-less Bluetooth receiver system
A 2.4 GHz CMOS blocker filtering low-noise amplifier (BF-LNA) suitable for Bluetooth? application is presented. The circuit employs a differential amplifier topology with a current mirror active load and a notch filter. Each path amplifies differentially with the common mode input signal, but there is a notch filter rejecting only the wanted signal at one path. By subtracting the two signals from
Optimization of circular antenna arrays of isotropic radiators using simulated annealing
This paper presents the design optimization of circular antenna arrays of isotropic radiators using simulated annealing. The problem has been formulated to achieve a desired value of sidelobe level and a minimum possible value of beamwidth. This is accomplished by jointly optimizing the excitation amplitude and spacing between elements. Simulation examples have been given and comparison has been c
Measurement of the density of magnetized fusion plasma using microwave reflectometry
About 25 years have elapsed since the first measurement by a FW-CW (called fast sweeping) reflectometer of the electronic density in magnetized fusion plasma. Substituting tube sources with solid-state components has resulted in a decrease of the sweeping time from the millisecond to the microsecond range. Based on voltage control oscillators and on active frequency multipliers, four profile refle
A 40 Gbps electro-absorption modulator integrated laser modeling method for optical transmitter in ultra-wide band radio-over-fiber systems
The great interest of optical fiber links in communicating systems especially in ultra-wide band (UWB) communications has grown up in the last decade and requires co-simulation for mixed circuits design exploiting both optical and microwave domains. In this paper, we report an original modeling method of an electro-absorption modulator associated with a distributed-feedback laser to simulate an op
Negative index from asymmetric metallic cut wire pairs metamaterials
Metamaterials made of exclusively metallic cut wire pairs have been experimentally demonstrated to exhibit a negative refractive index at optical frequencies. However, other related works on slightly different wire and plate pairs have not shown a negative index. In this paper, we present the analogy between previously reported S-shaped metamaterials and asymmetric cut wire pairs by a simple unify
SIP antenna on 0.13 µm SiGe technology at 79 GHz for SRR automotive radar
This paper describes the analysis and the design of an integrated antenna on 0.13 µm SiGe BICMOS technology. A non-resonant dipole antenna integrated on SiGe is electromagnetically coupled to a radiating element reported on a printed circuit board (PCB) substrate. This integrated solution, also compatible with system in package (SIP) concept, provides significant improvements with respect to direc
An RF spectrometer for fast wide band measurement
A new type of spectrum analyzer using RF interferometry is presented. The stationary wave integrated Fourier transform spectrometer is dedicated to the measurement of transient wideband signals. The spectrometer is mobile and cheap. It consists of spatial samplers placed along a waveguide ended by a short circuit. The standing wave caused by the short circuit is sampled and the spectrum is obtaine