A tunable multi-band CMOS LNA for mobile WiMAX

In this paper, we present the design and implementation of a tunable multi-band LNA for the mobile WiMAX (802.16e) standard using 0.13 mum CMOS process. The target frequency bands include 2.5~2.9 GHz, 3.4~3.6 GHz, and 5.2~5.9 GHz. The proposed LNA uses coupling capacitors to select frequency band. This technique leads to an improvement in linearity and frequency dependency of linearity as well as to a reduction in chip area through eliminating additional band tuning inductors. The simulated IIP3 for this LNA is +2.2 dBm, +3.2 dBm and +1.43 dBm at the lower, middle and upper bands respectively. It provides a power gain of 10 dB, a noise figure below 2 dB and S11 of 10.5 dB at all three bands. The proposed tunable multiband LNA dissipates 7.5 mW considering a power supply of 1.2 V.