Research and Study

During my stay at UEC I am conducting my research within the Electromagnetic Compatibility laboratory, headed by Professor Kami. My research consists of theoretical modelling and experimental analysis of switched beam parabolic dish antennas. This research may hopefully be useful in microwave point to point communications and may have satellite antenna applications. I am currently in the 3rd year of a Ph.D programme in the School of Microelectronic Engineering at Griffith University.

Most Antenna design requires the solution of electromagnetic field problems which are computationally intensive. In recent years with the advent of the personal computer many design topics have been revisited in an effort to provide a exacting solution. This has led to a range of numerical techniques such as Finite Element Method (FEM), Finite Diference Time Domain (FDTD) and Method of Moments (MoM) becoming widely available. In addition to this, iterative calculations which require a large number of repititions are now easily performed.

This last point is highlighted by the area of my study. Focal point studies have been well documented, in particular by Y.T Lo in 'Antenna Design'. However, not all feed arrangements have been explored to take advantage of lateral offsetting. There have been a plethora of phased array designs and offset feed designs and the method of achieving beam switching has a common theme, that is to excite elements displaced from the feed. However, a design can be achieved that is suitable for some stiuations where RF power is not directly fed to elements in the feed system.

By using these parasitic elements it is possible to achieve the desired result in addition to keeping the structure simple and with very low cost. Ideal parastic positioning is determined by using Physical Optics Modelling as well as experiemental testing. Optimization techniques can be used in conjunction with the above to achieve a desired outcome.