Design and fabrication of microstrip tools for measurement of gain and circularly polarized radiation pattern

Abstract

An antenna is a device that is made to efficiently radiate and receive radiated electromagnetic waves. One type of antennas that fulfills most of the wireless system requirements is relatively a microstrip antennas . A microstrip antenna is a kind of antenna used to radiate ultrahigh frequency signal. The demand of small size electronic systems has been increasing for several decades. The physical size of systems is reduced due to advancements in integrated circuits, with reduction in size of electronic systems, there is also an increasing demand of small and low cost antennas. Conventional microstrip patch antennas , in general, have a conducting patch printed on a grounded substrates, and have the attractive features of low profile, light weight, a narrow impedance bandwidth , low efficiency , low gain, large ohmic loss in large feed network, low polarization purity and they can only be used in low power applications, easy fabrication and supports both linear and circular polarization. Micro strip antenna are widely used in various applications like in wireless communication system, satellite communication , radar systems , global positioning systems , radio frequency identification (RFID), worldwide interoperability for microwave access ( WiMax). The antenna training system that exists in the microwaves and antenna laboratory in the collage of engineering and technology has a great ability for research if further tools could be created , from previous projects in the microstrip field, a great need rose to measure the gain of linearly polarized microstrip antennas as well as the radiation patterns of circularly polarization microstrip antennas in the available 1GHz frequency band.