Microstrip Antenna Array Cell Design And The Mutual Coupling

As the main means of personal communication, the wireless mobile communication technology is developed very fast after entering the 21-century. The development of 3G system needs higher technology to increase the correspondence capacity and quantity. The International Telecommunications Union (ITU) has mentioned to use the IMT-2000/FPLMTS as 3G system. Smart antenna has the capability to process the signal with space and time, which makes the system design more freely and has enormous potential to increase the communication capacity. This article is to design the smart antenna array , which is the key technique of 3G system. Because microstrip antenna array is well known for its highly desirable characteristics such as small volume, light weight, and ease of linear polarization, it is one of the best choices which satisfy the needs above. The research emphasizes the wideband, high gain and analysis of the mutual coupling of microstrip antenna elements.The first part of the article includes analysis, design and experimentation of array elements. Chapter one is preface, introducing research background. The characteristics of smart antenna and the style of the arrays and the means to achieve wideband are discussed in research background. In chapter two, rectangular microstrip antenna has been analyzed by transmission-line and modal-expansion cavity models. We have discussed kinds of factors that affect the antenna's characteristics and manufactured both single rectangular microstrip antenna and double elements successfully. The measured results are compared with the simulation results of Ansoft HFSS, and we have got some engineering experiences of the thick substrate microstrip antenna in chapter three. The second part of the article completes analysis and calculation of mutual coupling between elements. A dyadic Green's function is developed for a grounded dielectric slab, which can be used to calculate the mutualcoupling between elements. Compared with Method of Moment, we have discussed the problems of singular points and convergence, and got the calculated results by C++ programming. The calculated results are compared with the measured ones, most of which are shown to be in good agreement.