Printed monopole antennas are indispensable candidates for WLAN, UWB, and RFID applications. Along with the small size, the antenna should preferably be low cost, light weight, less fragile and low profile. The main aim of this book is design, simulation, fabrication, and measurement of wide band antenna array. The derived transmission line model was found for a slot antenna by two methods. First, a simple and accurate model of the offset fed transverse slot radiator is introduced. The second method is equating the delivered power to a lossy transmission line and the radiated power by a slot. Next, the input impedance and performance of printed monopole antenna array are discussed. The mutual coupling between the array elements is reduced using Electromagnetic Band Gap (EBG) structures. The EBG structures are divided to: Defected ground structure (DGS), mushroom-like EBG, and uni-planar EBG. All the three types are discussed.