Q-Band Uplink Solid State Power Amplifier (SSPA)

QuinStar proposes to develop an efficient solid-state power amplifier (SSPA), operating at 44.5 - 45.5 GHz, with an output power of 45 W and a PAE of 35%. This will be accomplished by utilizing the latest state-of-the-art GaN device technology and innovative circuit design techniques. First, for the device technology, we propose to team with the industry leader, Northrop Grumman (NGAS). They have established an industry benchmark producing a PAE level of 80.7% with an associated output power of 7.9 W at 3 GHz. While below our frequency of interest, it indicates the ability of their GaN process to produce high-efficiency power. Secondly, we are proposing to utilize a switching mode of operation (Class-F) to enhance the device efficiency. While this method has demonstrated efficiencies of 80% at 2 GHz, it has never been attempted before at these millimeter-wave frequencies. Computer simulations at 44 GHz indicate that by using this method in conjunction with NGAS’s device technology, we can achieve MMIC PAE levels of > 40%. Finally, we plan to employ a high-efficiency H-tee combining network to combine 8 of these high-efficiency MMIC chips to realize an output power of 45 W.