Main Effects Ensured by Symmetric Circular Slots Etched on the Radiating Patch of a Compact Monopole Antenna on the Impedance Bandwidth and Radiation Patterns

Wireless Personal Communications - Three compact monopole ultrawideband (UWB) antennas with half-wavelength symmetric circular slots etched on the radiating patch and operating in the UWB spectrum...     

Multilayer Substrate Integrated Waveguide Six-Port Circuit

In this paper a new design of a six-port circuit based on multilayer substrate integrated waveguides (SIW) is presented. This design is based on the use of a multilayer structure aimed at reducing the dimension of the circuit while conserving the performances of the component. The designed SIW six-port is composed of two basic elements, a SIW power divider and directional coupler. These two elements are designed, optimized and matched to produce a better performance at the required operating frequency of 11 GHz. The results of simulations show that the new multilayer SIW six-port circuit has good performances including a good return loss and isolation under–20 dB and the transmission magnitude better than–10 dB. This multilayer SIW six-port has the advantage of a small size 160-34.8 mm; its width is about 50% smaller than the planar SIW six-port circuit, which helps to get a higher density of integration in telecommunication systems and allows much smaller devices to be conceived.A microstrip toSIWtransition is used in order to facilitate the integration of this component into other planar circuits. The structures are designed, simulated and optimized using the Ansoft HFSS simulation software.