Promising 6.0-12 GHz Low Noise Amplifiers by Combining Two Matched Amplifiers

Devices fabricated and modeled through TSMC 0.18 micron CMOS processes are used to design radio frequency amplifiers. Two different mechanisms are applied to produce low noise amplifiers (LNA) and Class-E power amplifiers (PA) at various center working frequencies. Both amplifiers at the same working frequency are thus put together to enhance the gain. The enhancement can be easily done because they are impedance-matched prior to the combination. Noise figures are always suppressed because LNA component is intentionally put ahead of PA component. Both components are integrated into one large component. This integrated component has the features of low noise figure and high power added efficiency. The linearity and the interference is to be shown. In this paper, the forward gain at 6.0 GHz center working frequency achieves 55.148 dB just as expected. Its magnitudes of both S₁₁ and S₂₂ in the Smith Chart do approach to zero. And its noise figure is as low as 1.175. A promising integrated circuit is then to be found. Using the same algorithm, one can also show other optional possibilities at different center working frequencies.