Research And Design Of Planar Slot Antennas

With its favorable characteristics of low side-lobe radiation and compact structure, the planar array antenna has already become a focus of antenna research. At microwave frequency band, the slot antenna has attracted much attention, because it is convenient to feed and easy to produce.In this thesis, the radiation principle and the structure of slot antenna are studied and the impacts on its performance of every structure parameter in a slot antenna design are analyzed. On this foundation, a design plan of planar slot array antennas is proposed. The design has some structural feature as follows: (1) with different dielectric layers and microstrip line structure to guide the electromagnetic wave effectively;(2) the feeding network formed of microstrip line can match with the radiating slots expediently;(3) in order to increase the bandwidth of the antenna, the wider slot and branched feeding microstrip line are adopted to form a double resonance. A large number of simulative experiments have been made to verify the design, and satisfactory numerical results have been obtained. Some experimental antennas have been made actually and the main parameters have been provided, such as radiation pattern, VSWR and input impedance ,etc.The experimental results indicate that this type of antenna with planar structure is thin, small and simple, the antenna has nice input characteristic and radiation characteristic and can be used to compose slot array antennas conveniently to form a narrow beam with low side-lobe and can utilize the signal power fully and reduce the electromagnetic pollution effectively.If its structure parameter can be adjusted slightly, the antenna can be used in other communication systems with different frequency bands, especially in the microwave communication system, which can reflect its structural advantage even more.