Circularly polarized mimo array antenna for 5.8 Ghz point-to-point communication

Abstract

Three different design of circularly polarized multiple input multiple output (CPMIMO) antenna for point-to-point communication is proposed in this thesis. All design involves with combination of three type of technique which are MIMO, CP and array in single antenna. The first design is constructed from four truncated patch etched on Taconic TLY-5 substrate with 2.2 and 1.575 mm of dielectric constant and thickness respectively. Meanwhile, second and third design is based on circular shape radiating element and fabricate on FR4 with 4.7 dielectric constant and 1.6 substrate thickness. Rectangular truncated circular polarized antenna (RTCPA) was designed using a simple technique to produce CP capability 2.24 dB axial ratio, while 90° phased shifted dual and tripled coupled CP-MIMO used 90° phased shifting element to produce 1.9 dB and 1.94 dB axial ratio. Convergence of CP capability within the MIMO array antenna is successfully realized by two arrays of four circular-segmented patch array radiating element. Apart from that, the antenna resonant frequency of 5.8 GHz is suitable for point-to-point backbone communication system. All anechoic chamber's and reflection coefficient measurements agrees well with the simulation result. The combination of MIMO array antenna with circular polarization characteristics will multiply the gain of transmitter to achieve a last mile performance while simultaneously avoiding significant attenuated signals under adverse atmospheric conditions. The combination of two-port array antenna will enhance the gain of transmitter to achieve a last mile performance while simultaneously avoiding significant attenuated signals under adverse atmospheric conditions (bad weather). This thesis focuses more on MIMO system that are used in 5.8 GHz point-to-point communication.