A Design Technique For Linear Desensitized LNAs
Abstract
A new analytical design procedure utilizing adding
a parallel amplifier for low noise amplifiers (LNA) is presented.
In this method, the linearity and noise figure (NF) of the LNA is
investigated in order to improve the LNA performance. Using the
noise Correlation matrix (CA), the noise parameters of the paral-
lel network is calculated. It is proven that using this method, the
input impedance is less sensitive to noise matching. To evaluate
the proposed approach, two different LNAs using single and two-
parallel paths are designed and the Electromagnetic momentum
(EM) simulation results are compared. EM simulation result for
the designed 9-12 GHz LNA with the 0.1-μm pseudomorphic
GaAs pHEMT model is reported to support proposed theories.
The results represent that using the parallel method the linearity,
input and output impedance matching, NF and gain can improve
with a 30% increase in power consumption.