It is proposed to study artificially soft and hard surfaces for practical applications. Artificially soft and hard surfaces can be realized by a reactive and anisotropic loading of a conducting material, This loading can, for example, be done by using the well-known corrugations or using a cheaper method of etching conducting strips on a grounded dielectric slab. To perform this study, it is necessary to modify some existing numerical codes to adopt modeling these surfaces and develop analytical solutions of some canonical problems for verification purposes. The numerical tools will be general witch can be employed to easily model any detailed structure of antennas and scatterers. Two numerical techniques will be adopted, the finite difference time domain technique (FDTD) the method of moments techniques. The two methods will be used to complement each other and model many complicated structures. The graduate student will be trained to learn these techniques and to be able to do the modifications to the codes. Then, the process of designing new antennas and scatterers will begin. Some of the interesting problems are reducing the coupling between microstrip array elements to eliminate the blind effect with lower scanning elevation angles, reducing leakage of electromagnetic waves from microwave ovens, reducing the heat consumption in high power applications to increase device efficiency and reducing the cost of the cooling system. Smart antennas used in base stations require a decrease of the support structure effect on the radiation patterns and many other applications. Base stations requires the study of the radiation from antennas such as dipoles, slots, and microstrip antennas in the presence of infinite cylinders with arbitrary cross-section of composite materials. Many of these applications will be constructed and tested and verified with the numerical results. To analyze strips loaded surfaces and corrugated surfaces in an efficient way, new asymptotic boundary conditions are developed and will be implemented in the numerical codes. These asymptotic boundary conditions are referred to as asymptotic strip boundary conditions (ASBC) for strips loaded surfaces and asymptotic corrugation boundary conditions (ACBC) for corrugated surfaces. These boundary conditions will facilitate the study of arbitrary and finite surfaces that have periodic strip loading or corrugations. The new boundary condition will simplify the numerical modeling of these surfaces and Facilitate using them in practical applications. Therefore, these new asymptotic boundary conditions will be implemented in the method of moment codes and FDTD code. In some applications, the impedance boundary condition (EBC) can also be used efficiently whenever it is possible to accurately obtain the equivalent surface impedance. Therefore, the EBC will be also considered. We have presented a few examples to show that these boundary conditions can be successfully implemented and used with practical applications. This study also may develop novel ideas to obtain the desired radiation characteristics of antennas by simple implementation of the soft and hard surfaces. This may be used to improve the performance of the wireless communication devices, and microwave ovens, and simultaneously reduce the danger of the electromagnetic waves and their biomedical effects on human bodies. The findings of this work will be published in the literature, and introduced to the class room, and a comprehensive study may be published in a book.
