Title :
A Common Gate mixer with transconductance nonlinearity cancellation
Author_Institution :
Sch. of Electron. & Electr. Eng., Yonsei Univ., Seoul, South Korea
Abstract :
A highly linear common gate (CG) mixer is designed using transconductance linearization technique combined with elimination of harmonic feedback effect. One of the major contributors of third order nonlinearity in the mixer is the second derivative of transconductor (gm"). The Multiple Gated Transistor (MGTR) technique is employed in the transconductor of CG mixer to linearize the mixer. Also, an RF current source is used to remove harmonic feedback components which limit IIP3 enhancement. With CG MGTR transconductor, a LC folded cascode current commutating mixer is proposed. The proposed CG mixer for 900 MHz CDMA application is designed with 0.13 ¿m CMOS technology. Simulation result shows that conversion gain of 7 dB NF of 15 dB and IIP3 of 20 dBm while consuming 5.4 mA at 1.2 V supply. Compared with conventional design, the proposed one shows 10 dB IIP3 improvement.
Keywords :
circuit simulation; code division multiple access; insulated gate bipolar transistors; mixers (circuits); saturable core reactors; CDMA application; CMOS technology; RF current source; cascode current commutating mixer; current 5.4 mA; frequency 900 MHz; harmonic feedback effect; highly linear common gate mixer; multiple gated transistor; noise figure 7 dB to 15 dB; size 0.13 mum; transconductance linearization technique; transconductance nonlinearity cancellation; voltage 1.2 V; CMOS technology; Character generation; Feedback; Gain; Linearization techniques; Multiaccess communication; Noise measurement; Radio frequency; Transconductance; Transconductors; CMOS; Common Gate mixer; Linearity; Mixer;
Conference_Titel :
ASIC, 2009. ASICON '09. IEEE 8th International Conference on
Conference_Location :
Changsha, Hunan
Print_ISBN :
978-1-4244-3868-6
Electronic_ISBN :
978-1-4244-3870-9
DOI :
10.1109/ASICON.2009.5351319
