A Wideband Contactless and Bondwire-Free MMIC to Waveguide Transition

Wideband 5-bit MMIC Digital Attenuator With High Precision

This paper mainly introduces the Wideband 5-bit MMIC digital attenuator with high precision. Firstly, the theories of basic GaAs digital attenuator MMIC’s configurations are searched. Secondly, every possible configuration is contrasted, subsequently, appropriate topology is selected for each stage. This attenuator has been realized by 0.5!m GaAs pHEMT process. Simulation results of the digital...

Topology Optimisation of Wideband Coaxial-to-Waveguide Transitions

To maximize the matching between a coaxial cable and rectangular waveguides, we present a computational topology optimisation approach that decides for each point in a given domain whether to hold a good conductor or a good dielectric. The conductivity is determined by a gradient-based optimisation method that relies on finite-difference time-domain solutions to the 3D Maxwell's equations. Unli...

The Transition From Centralized to a Free Economy Within the Framework of Regional Cooperation

Coplanar Waveguide-fed RectangularSlotAntennafor Ultra-Wideband Application

This study describes a tunable coplanar waveguide fed (CPW) rectangularslot antenna to work within ultra wide band (UWB) for the future communication systems. This slot antenna of area 30*20mm is designed on a FR4 substrate and its operation was tested in terms of return loss and gain. The developed antenna shows VSWR  2 bandwidth of 800MHz in 0.7-1.51GHzband as well as bandwidth of 6.06GHz in...

Rectangular Waveguide to Coax Transition Design

question I am frequently asked is, “Why do the antenna dimensions in the W1GHZ Microwave Antenna Book — Online not include the probe dimensions (for the transition from waveguide to coaxial transmission line)?” The answer is that the transition is part of the transmission line, not the antenna, and does not directly affect the performance of an antenna. The transition may be right at the antenn...