Non-linear performance in power amplifiers and LNA at 900 MHz and 1900 MHz by using low-level voltage supply

This work is related to different high-linear low noise amplifiers (LNA) and high-efficiency power amplifiers (PA) performance at 1900 MHz and 900 MHz, respectively, concerning electromagnetic compatibility for being used in personal communication systems. A class A and E PAs and a common-emitter degenerated by inductance (CEDI) and an active feedback common-emitter (AFCE) LNAs were designed, simulated and compared in relation to their intermodulation product performance. The nonlinear and efficiency characteristics of a low-voltage supplied high-efficient class E PA for ISM band systems are reported. Concerning low-level voltage supplied LNAs, a very low nonlinear behavior was obtained, considering the 1 dB compression point, the intermodulation products and the third-order interception point in a wide frequency range. Such structures were polarized with 2.4 V and by using SiGe HBT as active elements.