Design of a Corner-Reflector Reactively Controlled Antenna for Maximum Directivity and Multiple Beam Forming at 2.4 GHz

• Published in: IEEE transactions on antennas and propagation Vol. 59; no. 4; pp. 1132 - 1139
• Main Authors: Dimousios, T D, Mitilineos, S A, Panagiotou, S C, Capsalis, C N
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.04.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna radiation patterns; Antennas; Applied sciences; Arrays; Beam steering; Business and industry local networks; Chromium; corner reflector-electronically steerable passive array radiator CR-ESPAR; Directive antennas; Directivity; Exact sciences and technology; Finite element methods; Gain; Gallium; Genetic algorithms; Networks and services in france and abroad; Optimization; radiation pattern oscillation; Radiocommunications; reflector; Reflectors; Systems, networks and services of telecommunications; Telecommunications; Telecommunications and information theory; Teleprocessing networks. Isdn; Transmission and modulation (techniques and equipments); transmit diversity; Wireless communication; Wireless communications; Passive component; Performance evaluation; Wireless LAN; Base station; Wireless telecommunication; transmit diversity; Reflector; Adaptive antenna arrays; Beam forming; Implementation; Optimization; Reflector antenna; Directivity; Beam steering; Resonance frequency; Radiation pattern; Antenna array; Input impedance; Coverage; corner reflector-electronically steerable passive array radiator CR-ESPAR; Case study; Genetic algorithm; Standing wave ratio; radiation pattern oscillation; Steerable antenna
• ISSN: 0018-926X; 1558-2221; 1558-2221
• DOI: 10.1109/TAP.2011.2109348

Electronically steerable passive array radiator (ESPAR) antennas constitute a promising research field and are expected to play important role in future wireless communications. In this paper, a new approach in ESPAR antenna design for base station applications is proposed. A corner-plate reflector is combined with active and passive (reactively loaded) elements in order to implement a corner-reflector ESPAR (CR-ESPAR) configuration. It is shown that when combined with corner reflectors in order to sectorize the coverage area, an ESPAR antenna offers multiple radiation patterns with higher directivity and resolution. A case study of a CR-ESPAR suitable for 2.4 GHz ISM applications is demonstrated, where the performance of the structure is optimized with respect to resonance frequency, input impedance, and multiple switched-beam patterns configuration. The optimization of the array is performed using a Genetic Algorithm (GA) tool as a method of choice, achieving a maximum gain equal to 14 dBi for a 30°3 dB-beamwidth and a gain of 11 dBi for a 45°3 dB-beamwidth, while the VSWR is kept below 1.7 in all cases. Due to its limited physical size, the proposed CR-ESPAR can be used as a portable antenna for deployment in WiFi, WLAN and other applications.