Based On The Mutual Coupling Effects Of Broadband Phased Array Technology Research

With the rapid development of modern wireless electronic technology, phased arrays are widely used in radar and communication systems. Broadband or even ultra-wideband antennas are usually required in phased arrays. Thus, broadband phased arrays have special values in terms of both the academic study and practical applications. The traditional broadband phased arrays are based on the concept of designing an element with desired bandwidth in isolation first and then making up a broadband phased array. Due to the mutual coupling effects between elements, the bandwidth enhancement of the phased array is usually limited. This thesis presents some studies on a novel broadband phased array based on the mutual coupling effect, which has been proposed in recent years. The thesis mainly contains the following several parts:Firstly, the importance and research status of broadband phased arrays are introduced. Some basic theories for the analysis of the broadband arrays based on mutual coupling are presented in detail.Secondly,in order to perform the optimal design of the array elements for the broadband phased array based on mutual coupling, an optimization approach based on the combination of commercial electromagnetic simulation software and Differential Evolution algorithm is proposed in the thesis. The form of the elements making up the broadband phased array based on mutual coupling is optimized using this approach. A broadband linear phased array with a large scan angle and a bandwidth of more than 4:1 is achieved.Thirdly, in respect of designing feed structure of linear broadband phased array, this thesis proposed a staggered structure of tapered microstrip balun array, which improves the transmission and enables the connection to SMA connectors. Moreover, a simple broadband feeding network for the 1×16 linear phased array is proposed designed.Finally, preliminary experiments are presented for theoretical verifications. Measured results show that the designed 1×16 linear phased array can be used to obtain broadband properties.