In this paper, a fourth-order, 3.5-MHz, low-pass elliptic Gm-C filter employing low-noise, low-voltage transconductance amplifiers is presented. A new technique to enhance the linearity of the Gm-C filter is proposed. Furthermore, the nonlinear behavior of the filter caused by nonlinear behavior of transconductors with determined input amplitude is discussed. HSpice simulation results of the 1.8-V filter in a 0.18 /spl mu/m CMOS process show a THD of less than -44dB for 0.6V/sub pp/ input signal and an input-referred noise of less than 45 nV//spl radic/Hz in worst case. The current consumption of each OTA is 1.5-mA.