Description: AlGaN/GaN MMICs on SiC substrates will be utilized to achieve Power Added Efficiencies (PAE) in excess of 60%. 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 J. The power output goal of a single X-band PA module is 50W, and the power output goal of the Ka-band PA module is 10W. In turn, these power modules will be combined using novel combiner topologies including but not limited waveguide and radial power combiners in order to achieve the high power goal of 1kW at X-Band and greater than150W at Ka-band. 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 combiner configurations will be simulated using 2.5D and 3D electromagnetic field solvers. The power combining strategies will be evaluated for overall system efficiency, size, and weight trade-offs.

Benefits: The proposed solution will have a solid market in the digital broadcasting of TV and video as well. Satellite terminal manufacturer ViaSat Inc. has recently announced that its huge ViaSat-1 Ka-band broadband satellite is under budget and on schedule and that the market for Ka-band satellites worldwide is expanding for consumer, mobile and military use. Company Chief Executive Mark Dankberg said demand is rising so quickly that ViaSat would not rule out ordering a second all-Ka-band satellite even before ViaSat-1 is launched in 12 months. The Ka-band community ViaSat hopes to create with Eutelsat, Yahsat and others is also laying claim to mobile-broadband applications for commercial aircraft and maritime customers. It is estimated that over time, 10 to 20 percent of ViaSat-1's revenue is likely to be from military and commercial mobile-broadband customers

One prominent application of the proposed technology is NASA's Deep Space Network, aka DSN, which operates mostly in X-band and Ka-band. The huge antennas of the Deep Space Network are currently tracking different missions including two NASA Mars Exploration Rovers, Spirit and Opportunity. By 2020, the DSN will be required to support twice the number of missions it was supporting in 2005, because the new space probes contain scientific instruments that produce much more data than on earlier missions. The communication link with earth is already a bottleneck that limits the use of certain instruments and it seems that the demanded data rate of payloads will continue to increase. The proposed solution will be the most high-power solid-state Ka-band amplifier ever used for deep space communication, and will lead to future improvements in ground facilities and spacecraft hardware, providing a significant potential increase in data rate in deep space communication.