Broadband high frequency low noise amplifiers for connected phased array feeds

A low noise amplifier (LNA) with 30 K noise temperature over a wide frequency range from 0.9 to 3.5 GHz is presented. The LNA to be described is suitable for high frequency connected arrays such as Phased Array Feeds (PAFs) operating in the 0.5 to 4 GHz frequency range. The LNA is implemented with unpackaged transistors. It combines single ended configurations to form a balanced amplifier with differential signal-and noise-match impedances in the order of 300Ω. Modeled results show a noise temperature of 48 K over the 0.5 to 4.0 GHz band for 150O input impedance.