Some investigations on techniques to suppress surface wave propagation in circularly polarized microstrip patch antenna

Abstract

The microstrip patch antenna is extensively used in wireless communication purposes because of its compact size, planar design and economical aspects. Planar Micro strip antennas finds applications in most of the Microwave and Millimeter wave systems since 1970. They have many advantages such as low profile, light weight, conformal nature, and lower cost of production, robust in nature. Microstrip Antennas are compatible with microwave monolithic integrated circuits (MMIC s) and optoelectronic integrated circuits (OEIC). Due to the merits, they have been utilized in most of the applications of mobile radio, satellite communications, radars, remote sensing, missiles, medical and many others. Besides the obvious advantages they have disadvantages such as low gain, narrow bandwidth and poor radiation efficiency. In spite of providing the designer the above mentioned advantages, the antenna suffers from serious hindrances of surface wave propagation and polarization mismatch. The suppression of surface waves propagation in the dielectric substrate have been focused upon. Extensive Literature review has been done on the techniques to suppress surface wave suppression in microstrip patch antennas. The Electromagnetic bandgap structures designed with the help of artificial dielectrics prove to be most suitable technique to suppress surface wave propagation and power loss. Artificial dielectrics designed using high impedance substrate has been proposed. newline