Highly Linear Gallium Nitride MMIC LNAs

In this paper, two Low Noise Amplifiers designed in Gallium Nitride HEMT MMIC technology are presented. The focus of the designs is to achieve good linearity at low power consumption and acceptable noise figure. The first design achieves an OIP₃/P_DC of 12 using traditional LNA design techniques. In a second design, the OIP₃ is improved by 2 dB, raising OIP₃/P_DC to 19, among the highest figures reported for GaN LNAs. This is achieved by using both inductive source feedback and drain-gate RC feedback.