IEEE Microwave and Guided Wave Letters

We report the development of a V-band monolithic power amplifier based on 0.1 μm gate-length pseudomorphic HEMT's. The two-stage amplifier has demonstrated record performance at 60 GHz on the first design pass: 272 mW output power with 9.4 dB power gain and 24% power-added efficiency. The amplifier was designed for high-reliability communications applications, with passivation, good linear... View full abstract»

Higher-order absorbing boundary conditions are compared to the recently introduced Berenger perfectly matched layer (PML) absorbing boundary conditions (ABC). Reflections caused by the ABC's are examined in both the time and frequency domains for the case of a line source radiating in a finite computational domain. It is shown that the PML ABC significantly reduces reflections from the truncation ... View full abstract»

The relation for intermodulation distortion (IM) levels in cascaded stages is based on the worst-case assumption that intermodulation products at the output of each stage combine in phase. However, because there is no apparent reason why IM products should always combine in phase, efforts are customarily made to discard this assumption. Using Volterra analysis, we show that, in certain cases, the ... View full abstract»

The use of a molecular beam epitaxy engineered InGaAs/GaAs semiconductor structure to quasioptically modulate a millimeter wave Gaussian beam using an optical control signal has been demonstrated. The RF transmission is modulated spatially by the optically generated excess carrier density. Low optical intensities are sufficient due to the long recombination lifetime achieved in the nipi-doped stru... View full abstract»

The paper presents a method of evaluation of cutoff frequencies of a guiding structure consisting of two eccentric circular arcs with edges shorted by conducting planes. Combination of conformal transformation and method of finite difference is used for the analysis. The general formulation is applied to the limiting cases of lunar guide and also the guiding structure of semicircular cross section... View full abstract»

CPW-fed multiple-slot antennas have been developed for active arrays and integrated antennas. This letter describes how the antenna can be engineered for a self-resonant 50-Ω input impedance for various substrate parameters, and the concepts are verified using a three-slot antenna on εr=2.2 substrate and a five-slot antenna on εr=9.8 substrate. These antennas ... View full abstract»

An unexpected nonreciprocal behavior is observed on Magnetostatic Forward Volume Waves (MSFVW) Straight Edge Resonators (SER's) using YIG films. The nonreciprocal effect is theoretically predicted by taking into account the demagnetizing effect of the DC biasing magnetic field when calculating the forward and reverse propagation constants of MSFVW inside the YIG film. Hence, a nonreciprocal scatte... View full abstract»

The contribution presents a new implementation of the absorbing boundary condition for structures where traditional ABC's perform poorly because of high dispersion. The proposed approach consists in the application of time domain diakoptics combined with the expansion of the impulse response into series of Laguerre polynomials. The application of Laguerre polynomials allows fast recursive calculat... View full abstract»

Dependence of performance of a Gunn Doppler self-oscillating mixer on the oscillator loaded quality factor, bias voltage and bias circuit resistance is investigated theoretically and experimentally. The analysis is based on consideration of stability principle and average voltage-current characteristic of a Gunn oscillator. Location of the operating point of the best performance of a Gunn Doppler ... View full abstract»