Research And Design Of UWB LNA And Mixer

With the advantages of high data rate, low cost and low power, UWB wirelesscommunication technology has great application potential and becomes the mostcompetitive one of the wireless communication technology recently. UWB low noiseamplifier and mixer are the key modules of an UWB RF receiver. The research anddesign on UWB LNA and mixer are of great importance to the popularity andapplication of UWB communication technology.This paper briefly introduces the UWB wireless communication technology, andanalyzes the domestic and international research status of UWB LNA and mixer.Meanwhile, the advantages and disadvantages of various circuit structures aresummarized. Then a new highly linear low-voltage UWB LNA and a low-voltage lowpower UWB mixer are proposed, based on the reading of literature and analyzing oftheory. The main achievements of this work consist of the following aspects:(1) A highly linear low-voltage UWB LNA working at2.1~7GHz is presented. Acommon-gate input structure is employed for UWB impedance matching. In order toimprove the linearity of the proposed LNA, a common-source post-distortiontechnique is adopted. Simulation results show that the proposed LNA exhibits inputand output reflection coefficient of less than-10.7dB, a max power gain of14.5dB, anoise figure of3.1~3.9dB and an input third order intercept point of21dBm, whileconsuming7.3mW from a0.8V power supply.(2) A low-voltage low power UWB mixer working at3~10.6GHz is presented.The proposed UWB mixer is based on double balance Gilbert mixer. Due to utilizingthe substrate bias and low-voltage current bleeding techniques, the supply voltage andpower dissipation of the proposed mixer are effectively reduced. Simulation resultsshow that the proposed mixer achieves a conversion gain of12.1~18.8dB, a singlesideband noise figure of7.1~11.4dB, an1dB compression point of-10dBm and aninput third order intercept point of-1.8dBm, while consuming1.9mW from a0.8Vpower supply.The proposed circuits are simulated in0.18μm RF CMOS technology by ADSand Cadence software. Compared with the similar circuits which were reported recentyears, the proposed LNA has certain advantages of linearity and supply voltage, andthe proposed mixer has more superior performance of power dissipation, supply voltage and noise.