AlGaN/GaN devices on SiC substrates will be utilized to achieve Power Added Efficiencies (PAE) in excess of 85%. These wide band-gap solid-state semiconductors will be used in novel Power Amplifier (PA) topologies such as Current Mode Class D (CMCD) and Class E. The power output goal of a single P-band PA module is greater than 50W, and the power output goal of the L-band PA module is greater than 10W. In turn, these power modules will be combined in push-pull to balance configurations for higher power. Phase I will consist of choosing the devices sizes and topologies for the PA modules, and performing extensive modeling and simulation, especially for the large signal non-linear operation with harmonic terminations required to achieve the high efficiency goals. In addition, various power configurations will be simulated to achieve a 50 Ohm output without extensive impedance matching transformations to improve efficiency and useable bandwidth. The power sizing strategies will be evaluated for overall system efficiency, size, and weight trade-offs.