Study and Design of the Dual-Band Low Noise Amplifier

A dual-band source-inductive-degeneration cascoded low noise amplifier, whose center frequencies are 940 MHz and 2020 MHz respectively, based on common usage of the component independent of the frequency, was investigated and designed in this paper. The interstage mutual coupled inductors provide the required input impedance matching and interstage impedance transformation. The circuit´s reverse isolation for the cascoded LNA is improved. The parallel capacitance between the MOSFET´s gate and source optimize noise factor of the LNA. The matching network design, the noise optimizing were analyzed hereof. The development of LNA and the methods of NF optimization were studied. The designed LNA achieves power gains of 26 dB and 25 dB, and minimum noise figure of 1.1 dB and 2.0 dB, and power of 10.5 mw with 1.5 voltages respectively.