Low-cost EHF power amplifiers

The authors investigate the lowest-level building block of the EHF amplifier chain, a 1.5-W amplifier module that can be combined for higher power. Based on pseudomorphic high electron mobility transistor (HEMT) technology, this amplifier incorporates 900-μm gate-width devices that demonstrate a 0.5-W output power and up to 34% power-added efficiency. Four of these are to be combined in the output state to generate 1.5 W of power. An integrated product development approach for the device and modules is being used to focus on reproducibility and manufacturing issues earlier in the development cycle to ultimately lower the overall terminal costs. By designing a common yet flexible amplifier building block, a limited, cost-effective set of subassemblies will meet the requirements for all the various EHF programs, effectively maximizing their application across a broader market