With the ever-increasing demand on wireless spectrum by wide bandwidth applications, such as 3G mobile phones at RF frequencies, Multipoint Video Distribution System (MVDS) and Local Multipoint Distribution System (LMDS) in the millimeter-wave frequency range, there is a growing need to exploit higher and higher frequencies. So, mmwave field is becoming a rapidly emerging area of research. Keyw...

Conventional altimeters include nadir looking colocated 18-37 GHz microwave radiometer to measure wet tropospheric path delay. These have reduced accuracy in coastal zone (within ~50 km from land) and do not provide wet path delay over land. The addition of high frequency channels to Jason-class radiometer will improve retrievals in coastal regions and enable retrievals over land. High-frequenc...

Newly developed multi-layer inductors on GaAs threedimensional MMICs are presented. We analyzed single-, double-, triple-, and quadruple-layer stacked-type inductors in what may be the first report on inductors on a GaAs MMIC with three or more layers. The performance of singleand multi-layer inductors was measured and calculated by electromagnetic field simulation. The multi-layer inductors pr...

A four-device broadband solid-state power amplifier, which is based on radial waveguide power-dividing/combining circuit, has been investigated in this work. The fabricated power amplifier combining four monolithic microwave integrated circuit power amplifiers shows a 12–16.6 dB small-signal gain over a broadband from 6 to 14 GHz. The measured maximum output power at 1 dB compression is 25.6 dB...

Artificial Intelligence (AI) techniques are applied to develop a framework for the design and layout of MMIC circuits. This framework addresses key aspects of the design process, from circuit specification and initial design decisions through to final layout and preparation of the circuit for fabrication. A number of knowledge-based systems are incorporated into the framework to assist in speci...

This paper proposes a broadband asymmetrical monolithic microwave integrated circuit (MMIC) Doherty power amplifier (DPA) using 0.25-μm gallium-nitride process with compact chip size of 2.37 × 1.86 mm2 for 5G communication. It adopts an unequal Wilkinson’s divider ratio 2.5:1, where 71.5% the total is transferred to main higher gain. Different input matching networks are used offset phase diffe...

Most reported spatially combined or quasioptical amplifier arrays exhibit resonant narrowband performance (<10%) and have not addressed thermal management issues. We report a waveguide-based spatial combining scheme using broadband tapered-slot transitions, capable of realizing full waveguide band coverage (40% fractional bandwidth) with good thermal properties. An X-band prototype using eight ...

Mitsubishi Electric Corporation has developed a millimeter-wave radar for automotive application. Monolithic microwave integrated circuits (MMICs), developed specifically for this application by Mitsubishi Electric, are used for the radio-frequency (RF) module to obtain outstanding radar performance. This millimeter-wave radar incorporates a signal-processing unit in the radar head, resulting i...

Quasi-optical (QO) active circuits have originally received interest for power generation by large-scale power combining of solid-state devices at microwave and millimeter-wave frequencies. Here, we present an overview of QO components developed with functionality in mind, with an emphasis on bidirectional amplifier arrays for transmit/receive (T/R) front ends. We discuss possible advantages of...