Design and Analysis of UWB Down-Conversion Mixer with Linearization Techniques

Frequency translation which converts the original signal to a much lower baseband frequency signal is a vital role in the RF receiver design. In this work, a high linear down-conversion Gilbert cell mixer at 100MHz is designed using TSMC 0.18μm RF CMOS process. Linearity is an important performance measure in RF circuits particularly in mixer design. In this paper, the two types of linearization techniques called Cross Coupled Post Distortion (CCPD) and Multiple Gated Transistor (MGTR) are performed on wideband CMOS mixer and their performances are analysed. The mixer covers the frequency band of 3.1-9.5 GHz. The mixer with CCPD provides the conversion gain of 7.96dB with a noise figure of 14.66dB at 100MHz IF. The mixer with MGTR provides the conversion gain of 6.12dB with a noise figure of 14dB. The third order intercept point for these techniques is 3.33dBm and -1.365 dBm respectively. From this analysis, CCPD technique gives the high gain and high linearity for this UWB mixer. The circuit operates at the supply voltage of 1.8 V and the power consumption is 6.93mW. Key-Words: CCPD, down-conversion mixer, Linearization techniques, MGTR, UWB mixer.