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Compact dual-mode rectangular waveguide filters using square ridge resonators
A new class of compact rectangular waveguide filters is proposed in this paper. The key element is a square ridge resonator realized within a rectangular waveguide supporting the fundamental TE mode. The square ridge can support two modes resonating along orthogonal directions in the gap between the ridge and the opposite waveguide wall. This structure enables dual-mode degeneracy without the need
A rugged 100 W high-voltage vertical MOSFET L-band radar device
The silicon vertical MOSFET RF power amplifier described in this paper is the industry?s first to utilize high-voltage vertical technology. Operating under pulse conditions of 200 µs pulse width and 10% duty cycle, it delivers more than 100 W of peak power. Operating in Class AB with only 50 mA of bias current the device achieves more than 20 dB of gain and 47% power added efficiency at P1dB compr
Low-cost TRM technologies for phased array radars
Low-cost enabling technologies for T/R modules (TRMs) in phased array radars are proposed and analyzed in terms of technology, performance, and cost aspects. Phase and amplitude controlling integrated circuits (ICs) realized in a low-cost standard silicon process are demonstrated. The design of several ICs at the S-, C-, on X-band has shown that silicon germanium is a strong contender for gallium
Design and evaluation of 20-GHz power amplifiers in 130-nm CMOS
The use of 130-nm CMOS for power amplifiers at 20 GHz is explored through a set of power amplifiers as well as transistor level measurements. The power amplifiers explore single versus cascode configuration, smaller versus larger transistor sizes, and the combination of two amplifiers using power splitters/combiners. A maximum output power of 63 mW at 20 GHz was achieved. Transistor-level characte
Space-FFT-accelerated marching-on-in-degree methods for finite periodic structures
A fast, yet unconditionally stable, solution of time-domain electric field integral equations (TD EFIE) pertinent to the scattering analysis of uniformly meshed and/or periodic conducting structures is introduced. A one-dimensional discrete fast Fourier transform (FFT)-based algorithm is proffered to expedite the calculation of the recursive spatial convolution products of the Toeplitz?block?Toepl
Tunable microwave devices based on left/right-handed transmission line sections in multilayer implementation
Metamaterial transmission lines can be realized as a combination of right- and left-handed transmission line (TL) sections exhibiting positive and negative dispersion. This approach gives additional degrees of freedom for improving the performance of microwave devices. Artificial right- and left-handed sections, which are based on lumped-element unit cells consisting of inductance and capacitances
Digitally assisted equalization of third-order intermodulation products in wideband direct conversion receivers
An effective linearization technique capable of equalizing IM3 products resulting from an arbitrary out-of-band blocking scenario in a wideband direct conversion receiver is presented. IM3 products are regenerated in the RF analog domain of a low-power mixed-signal feedforward path and are used to cancel analogous signal terms in the original receiver at digital baseband via adaptive equalization.
Design and performance of multi-channel switched sequential amplifiers
This paper presents switched sequential amplifiers (SSAs) using reconfigurable directional couplers as power splitters and combiners. The SSA concept allows matching the efficiency characteristics to the amplitude probability density distribution of the applied modulated signal. Therefore the back-off efficiency can be increased significantly. A three-channel SSA can e.g. theoretically achieve a ?
A subharmonic front-end in SiGe:C technology for 94-GHz imaging arrays
The design of a subharmonic downconverter for 94-GHz imaging arrays in SiGe:C technology is presented. A three-stage differential low-noise amplifier (LNA) with lumped matching networks is used together with a subharmonic mixer driven by a single-pole local-oscillator poly-phase network to form the front-end. The LNA yields 15 dB gain at 94 GHz, while the mixer provides 5 dB conversion gain over a
X-band T/R-module front-end based on GaN MMICs
Amplifiers for the next generation of T/R modules in future active array antennas are realized as monolithically integrated circuits (MMIC) on the basis of novel AlGaN/GaN (is a chemical material description) high electron mobility transistor (HEMT) structures. Both low-noise and power amplifiers are designed for X-band frequencies. The MMICs are designed, simulated, and fabricated using a novel v