Switched Parasitic Smart Antenna: Design and Implementation for Wireless Communication Systems

Abstract

Smart antenna technology in applications such as the next-G wireless communication networks may improve the quality of service (QoS). One category of smart antennas is the switched beam smart antenna (SBA). These antennas can be grouped into plug and play antennas and adaptive internal antennas. Four types of switched beam smart antennas were investigated including a six monopole array on circular ground plane with conducting sleeve, five monopoles on a circular ground plane without a conducting sleeve, a reconfigurable monopole on a cylindrical hollow ground structure, and a reconfigurable adaptive internal antenna. The first two antennas were constructed with a switched parasitic array of elements combined with an RF circuit with microcontroller. Two of the four antenna prototypes were capable for steering the beam pattern automatically based on signal strength (RSSI) or bit error rate (BER) scanning. The two remaining antennas were designed for electronic beamforming and electronic frequency tuning. Both numerical and empirical investigations were undertaken to measure performance and investigate manufacture difficulties. The numerical investigations were undertaken using both the method of moment (MoM)-NEC and the finite element method (FEM)-HFSS modeling. The fabrication and testing in an anechoic chamber were used to explore the actual performance of the designed antennas. The fabrication of the last two types of antennas was not implemented. Further work is required to find the optimal design for all antennas investigated. This study suggests significant promise for these antennas in wireless networks.