A 1.2 and 2.4 GHz variable gain concurrent dual band low noise amplifier

This paper presents the design and implementation of a dual band low noise amplifier (DBLNA) operating at 1.2 and 2.4 GHz concurrently. The DBLNA employs a second-order matching network designed using frequency mapping and bandpass transformation technique. The DBLNA has two stages and employs cascode topology for high output impedance and better reverse isolation. Modified output load for dual band operation is designed to get optimum passbands and stop-band rejections. The designed DBLNA achieves a very high voltage gain of 43 dB and 26 dB and noise figure of 4.7 dB and 4.4 dB at 1.2 and 2.4 GHz, respectively. The LNA consumes 40 mW power from a 2V supply. The LNA gain can be varied from 5dB to 44dB by varying Vdd between 1.05V to 2.2V. The P1dB performance is -32 dBm and -18 dBm a 1.2 and 2.4 GHz, respectively.