Promising Low Noise Amplifiers in Various Frequency Bands from 1.8 GHz to 5.8 GHz

Transistors fabricated through TSMC 0.18 micro-meter CMOS process helps design radio frequency amplifiers. Low noise amplifiers (LNA) at various center working frequencies ranged from 1.8GHz to 28 GHz are presented in this paper. All amplifiers at different working frequencies are thus explored with appropriate impedance matching. Noise figures have been watched and linearity is looked up. Both the passive devices, including capacitor and inductor, contribute to generate null S11 and S22 for impedance matching. They are put together to form band pass filter and LC tank, which provides frequency identification of interest and enhances the gain. The linearity and the interference is to be shown. In this paper, the forward gain at 1.8, 2.4, 3.5, 5.0 and 5.8 GHz center working frequency achieves over 20.0 dB just as expected. Its magnitudes of both S 11 and S 22 in the Smith Chart do approach to zero. And its Noise Figure is as low as 1.175. AT 2.4GHz, optimized processes demonstrate that S21 can be improved and so is NFmin.