A 3–6 GHz Current Reused Noise Canceling Low Noise Amplifier for WLAN and WPAN Applications

A new ultra-wideband common gate low noise amplifier (LNA) for 3–6 GHz WLAN and WPAN applications is presented in which a current reused noise canceling structure utilized in the first stage not only provides a suitable noise performance, but also enhances the linearity characteristics of the LNA in a power efficient manner needed by WLAN/WPAN applications. The overall structure of the proposed LNA, consisting of three stages, namely input matching common gate stage with noise canceling, gain stage, and buffer one, is designed, laid out, and analyzed in 0.18 µm RF CMOS process. The LNA has a noise figure of 3.5–3.6 dB, a high and flat power gain of 20.27 ± 0.13 dB, and input and output losses of better than −11 and −14 dB, respectively, over the entire frequency band of 3–5 GHz, while these parameters are 3.5 dB, 20.75 ± 0.25 dB, −15 and −9 dB for the frequency band of 5–6 GHz, respectively. IIP2 and IIP3 of the proposed topology are equal to 25.9 and −1.85 dBm, respectively, at 4 GHz frequency. The proposed LNA has 15.3 mW power dissipation from a 1.8 V supply.