The rapid growth in cellular communications has proved that wireless communication is viable for voice and data services. Traditional wireless devices are designed to deliver a single communication service using a particular standard. With the steady increase in new wireless services and standard, single purpose devices, dedicated hardware resources can no longer meet the user's needs. It is also expensive to upgrade and maintain a wireless system each time a new standard comes into existence. A feasible solution to make communication systems more flexible and user friendly can be achieved through the Software Defined Radio (SDR) concept. This book, therefore, provide design, simulation, implementation and verification of a proposed SDR system including six bandpass modems (modulation/demodulation) schemes with selectable technique between them. These modems satisfy the WIMAX standard. These modems are BPSK, QPSK, 8QAM, 16QAM, 32QAM and 64QAM.This book should be useful for researchers and manufacturers that work on development of wireless communication systems by using SDR emerging technology that has the advantage of flexibility over conventional radio systems.