Microwave imaging is an up coming excellent diagnostic tool to detect tumor tissues in early stages of cancer. Many findings in this direction have been reported till date. But most of the work is directed towards detection of breast cancer and very few literature is available on detection of skin cancer which is most common of all cancer types. This book focuses on development of a cost effective simulation tool for detection of skin cancer. The finite difference time domain (FDTD) method hybridized with various optimization techniques like neural network, bacterial foraging algorithm etc. have been used and proposed in this book that may result in an efficient and accurate CAD tool for skin cancer detection. Radar imaging approach for detection of tumor tissues requires antennas with high gain and small size. Some new antenna structures having high gain, directional radiation pattern and very small size have been designed and simulated. Concept of metamaterial has been applied to achieve antenna miniaturization.