focuses on the improvement of power efficiency in wireless communication systems, especially of mobile devices. Reviewing cutting-edge techniques for conserving power and boosting power efficiency, the book examines various technologies and their impact on consumer devices. It considers each technology, first by introducing the main physical layer components in recent wireless communication systems along with their shortcomings, and then proposing solutions for overcoming these shortcomings. The book covers orthogonal frequency division multiplexing (OFDM) signal generation and formulation and examines the advantages and disadvantages of OFDM systems compared to alternative multiplexing. It introduces one of the main drawbacks of OFDM systems, peak-to-average power ratio (PAPR), and discusses several PAPR techniques. It also explains how to overcome the main drawbacks of real-world OFDM system applications.