A new pole-zero technique for reducing thermal noise to design a very low noise figure UWB LNA

Abstract

In this paper, a new pole-zero technique for reducing thermal noise is represented. In the proposed new pole-zero method, by extracting the noise and voltage-gain equations of the amplifier, the zeros of the noise transfer function (TF) are managed, so that they are placed near the poles of the gain TF. Therefore, significant noise reduction is achieved in the condition of maximizing the small-signal gain. The proposed pole-zero management technique is investigated by designing a 4 to 9 GHz ultra-wide-band (UWB) low-noise-amplifier (LNA). The linearity and power consumption could also be taken into consideration as additional design criteria. The proposed UWB LNA benefited from complete input/output matching, average power gain of 13.5 dB, and average noise figure of 1.4 dB. Also, 1-dB compression point and IIP3 are -8.8 dBm and +9.2 dBm, respectively at 6.5 GHz. With 130 nm CMOS technology, the circuit consumes 20 mW from supply voltage of 1.2 V. The area of the chip with pads is 0.145 µm 2 .Keywords-low noise amplifier (LNA); pole-zero management method; noise cancellation; ultra-wide-band (UWB).