Study Of Broad Band And Wide Angle Scanning Phased Array Antenna

The phased array antennas have both huge military and civilian applications, some of which require higher performance of the antennas. The phased array antennas with broadband and wide scanning range features are in great demand. The principle and design method of broadband and wide scanning phased array antennas is studied in this thesis. And the thesis mainly consists of the following three parts:In the first two chapters, the development of the broadband wide-angle scanning antennas and the principle of phased array antennas are introduced. Secondly, fundamental limits of antennas' bandwidth and the theory of wide angle impedance matching are discussed. At the end of this part, the equivalent circuit and the wide band impedance matching method are introduced.In the third chapter, properties of infinite periodic tightly coupled array are discussed, and the equivalent circuit is established by the traditional method. Secondly the new equivalent circuit is proposed by considering the two order resonance effects of the antenna, and the equivalent circuit is used to design a broadband array. Finally, a 13 elements coupled array is analyzed, and the impedance matching method that loading the edge elements is verified.In the fourth chapter, the scanning angle feature of a dipole array is analyzed. Secondly a single frequency wide-angle impedance matching is achieved by using the method of impedance matching. Finally, by analyzing the relationship between the array's scanning angle, frequency and the reflection coefficient, an optimization method is introduced, which enhance the bandwidth and scanning angle of the dipole array.