Evolution of Monolithic Technology for Wireless Communications: GaN MMIC Power Amplifiers For Microwave Radios

This paper presents the progress of monolithic technology for microwave application, focusing on gallium nitride technology advances in the realization of integrated power amplifiers. Three design examples, developed for microwave backhaul radios, are shown. The first design is a 7 GHz Doherty developed with a research foundry, while the second and the third are a 7 GHz Doherty and a 7–15 GHz dual-band combined power amplifiers, both based on a commercial foundry process. The employed architectures, the main design steps and the pros and cons of using gallium nitride technology are highlighted. The measured performance demonstrates the potentialities of the employed technology, and the progress in the accuracy, reliability and performance of the process.