Title :
Determining Bandwidth Estimators and Matching Circuits for Evaluation of Chassis Antennas
Author :
Valkonen, Risto ; Lehtovuori, Anu
Author_Institution :
Univ. of Kiel, Kiel, Germany
Abstract :
This paper presents a procedure for determining the practically achievable bandwidth of a strongly frequency-dependent load impedance when using a simple matching circuit. The main target application is mobile handset antennas, which might be inherently nonresonant and thus the achievable bandwidth is not known from the input impedance. A straightforward and efficient algorithm for determining various bandwidth estimators is presented. A compact dual-band WLAN antenna is then designed, manufactured, and measured as an example application of utilizing the bandwidth estimators. Another example demonstrates how the bandwidth estimators can be used to determine a matching and decoupling circuit for a symmetrical dual-element antenna. The results show that the bandwidth estimators can be used as a supplementary tool in antenna design, transferring a part of the design challenge from electromagnetics to circuit design.
Keywords :
bandwidth allocation; mobile antennas; mobile handsets; multifrequency antennas; wireless LAN; achievable bandwidth; bandwidth estimators; chassis antennas; compact dual-band WLAN antenna; decoupling circuit; electromagnetics; frequency-dependent load impedance; matching circuit; mobile handset antennas; symmetrical dual-element antenna; Bandwidth; Broadband antennas; Frequency estimation; Impedance; RLC circuits; Topology; Circuits; Impedance matching; circuits; decoupling circuits; impedance matching; multifrequency antennas;
Journal_Title :
Antennas and Propagation, IEEE Transactions on
DOI :
10.1109/TAP.2015.2443862