Circuit Based Optimization of Radiation Characteristics of Single and Multi-Port Antennas

• Main Authors: K. Karlsson, J. Carlsson
• Format: Article
• Language: English
• Published: Spolecnost pro radioelektronicke inzenyrstvi 2009-12-01
• Series: Radioengineering
• Subjects: Embedded element pattern; optimization; multi-port antenna; antenna efficiency; antenna diversity; impedance matching.
• Online Access: http://www.radioeng.cz/fulltexts/2009/09_04_438_444.pdf

A method for analyzing and optimizing multiport antennas is presented and exemplified. The method was first presented in [1]-[3] and uses data from full wave electromagnetic field (EM) solvers in combination with circuit simulations for efficient calculations of radiation properties of multi-port antennas. The main advantage of the proposed method is that only a few full-wave simulations, which usually are time consuming, are needed when e.g. optimizing the matching circuits for a multi-port antenna. Since embedded element patterns are used, all relevant antenna parameters such as radiation efficiency, diversity gain, available MIMO capacity etc. can efficiently be computed for any port excitation and loading configuration. The methodology has been implemented in software called MPA (Multi-Port Antenna evaluator) which imports port response matrices and embedded element patterns from commercial full-wave codes and post processes the data making it possible to e.g. optimize capacity for a MIMO system. The optimization is done by changing the feeding and matching networks in a circuit simulator that is invoked by the MPA. Finally the software is used on two examples which are analyzed and optimized to illustrate the potential of the method.