Planar antennas

A Square Loop Antenna Using Hybrid High Impedance Surface and Four Way Wilkinson Power Divider

A simulation of a planar Square Loop Antenna (SLA) on a Hybrid High Impedance Surface including the feeding part using a 4 way Wilkinson power divider is shown in this article. Placing the planar antenna over a hybrid High Impedance Surface (HIS) can lower the overall antenna profile due to the unique reflection phase of the HIS. The planar SLA produces a semi doughnut radiation pattern which is suitable for vehicular communication. The effect of the feed network and cables on the antenna performance is considered. Read full article..

RFID Reader-Coil, 13.56 MHz

Radio Frequency Identification Systems (RFID) are widely used and allow advanced solutions for a variety of applications in the area of authentication, ticketing, access control, supply management, parking, payment, vending,etc. The example presented here is a RFID Readercoil "P81" from Legic Ident Systems and was modeled and solved using the frequency domain solver of CST MICROWAVE STUDIO® (CST MWS). The sensitivity of the computed complex input impedance with respect to substrate tolerances is computed and was compared to measurement data. Read full article..

Design of Circularly-Polarized Patch Antennas using CST MICROWAVE STUDIO®

An RFID Reader Antenna with the following specifications was designed: - Frequency: 908.5 - 914 MHz (In Korea) - VSWR: less than 2 with 50-ohm impedance - Polarization: circular - Axial ratio: less than 3 dB @ 908.5 - 914MHz - Gain: 6 dBi @ 1W transmitted power - Size and weight: as small as possible This article is published with the permission and courtesy of Prof. Bierng-Chearl Ahn and his colleagues at Chungbuk University, Korea. Read full article..

Analysis of a high efficiency reflector feed array

This article demonstrates the application of CST MICROWAVE STUDIO® (CST MWS) to the analysis of large reflector feed arrays. An array consisting of 19 elements was simulated but a larger array of more than 100 elements may also be simulated since the memory scaling with mesh cells in CST MWS is almost linear. The simultaneous excitation feature in CST MWS was applied to obtain farfield patterns in just a single simulation. A parameter sweep was also carried out to obtain the S-Parameters as a funtion of element feeding postion. Read full article..