A 0.1-26.5 GHz Wideband Low Noise Amplifier with Single Positive Supply

This paper introduces the design and performance of a GaAs MMIC low noise amplifier (LNA) for microwave measurement equipment. The broadband characteristics are achieved through the use of a distributed topology with cascode unit cells. A seven-stage topology is used to increase the gain of the LNA. The chip has high gain with a typical gain of 18 dB from 0.1 to 26.5 GHz, and the flatness of the gain is less than ±1 dB. Because of low common-base transistor’s capacitance, low collector-current operation, and optimum line-impedance matching, a low noise figure is also achieved in the circuit. Within the entire operating frequency range, the noise figure is less than 4.5 dB, and a typical value of 2.5 dB is found from 0.1 to 17 GHz. The 1 dB compression point of the amplifier is higher than 12 dBm for the output power. There is very good consistency between the experimental results and the simulation results.