High linearity 5.2 GHz CMOS up-conversion mixer using derivative superposition method

Abstract

This paper presents a high linearity and low power up-conversion mixer at 5.2 GHz for wireless applications. The design based on Gilbert-cell active double-balanced mixer using derivative superposition method for linearity is proposed in TSMC 0.18-µm CMOS technology. The linearity of the designed mixer is further improved by utilizing source degeneration inductors at transconductors stage. The up-conversion mixer converts an input of 100 MHz intermediate frequency (IF) signal to an output of 5.2 GHz radio frequency (RF) signal with a local oscillator (LO) frequency of 5.1 GHz. The post-layout simulation results indicated that the proposed method shows 5.7-dBm higher input third order intercept point (IIP3) than the conventional mixer. From the simulated results, the mixer achieves an IIP3 of 15.7-dBm, conversion gain of 6-dB, and 2.5-mW power consumption at 1.8-V power supply.