Title :
A 3 V 1.9 GHz CMOS low-distortion direct-conversion quadrature modulator with a RF amplifier
Author :
Wu, Chung-Yu ; Kao, Hong-Sing
Author_Institution :
Dept. of Electron. Eng., Nat. Chiao Tung Univ., Hsinchu, Taiwan
Abstract :
A 3 V 1.9 GHz CMOS low-distortion direct-conversion quadrature modulator with an RF amplifier is described. The circuit is implemented using 0.5 μm DPDM CMOS technology and dissipates only 95 mW (including power dissipation of RF amplifier) under 3 V power supply voltage. The unwanted lower sideband is below -80 dBc when the 0 dB normalized desired upper sideband is set at 1.9 GHz, corresponding to a small signal path mismatch. Moreover, the LO feedthrough and the second-order intermodulation are less than -80 dB. The third-order intermodulation of -60 dB is obtained. A current reuse technique is employed to save the power dissipation of RF amplifier such that the current in the negative resistor is reused in the gain stage. The gain of RF amplifier is 23 dB at 1.9 GHz center frequency. The power dissipation of RF amplifier is only 9 mW and smaller than in recent work
Keywords :
CMOS analogue integrated circuits; UHF amplifiers; UHF integrated circuits; electric distortion; intermodulation; modulators; 0.5 micron; 1.9 GHz; 23 dB; 3 V; 9 mW; 95 mW; CMOS low-distortion modulator; DPDM CMOS technology; LO feedthrough; UHF amplifier; current reuse technique; direct-conversion quadrature modulator; second-order intermodulation; third-order intermodulation; CMOS technology; Equations; Frequency modulation; Laboratories; Power dissipation; RF signals; Radio frequency; Radiofrequency amplifiers; Radiofrequency integrated circuits; Voltage;
Conference_Titel :
Electronics, Circuits and Systems, 1999. Proceedings of ICECS '99. The 6th IEEE International Conference on
Conference_Location :
Pafos
Print_ISBN :
0-7803-5682-9
DOI :
10.1109/ICECS.1999.813224
