Title :
A Low-Power WCDMA Transmitter With an Integrated Notch Filter
Author :
Mirzaei, Ahmad ; Darabi, Hooman
Author_Institution :
Broadcom Corp., Irvine, CA, USA
Abstract :
A filtering technique to attenuate the receive-band noise enables a 65-nm CMOS WCDMA transmitter to achieve an output noise level of -160 dBc/Hz at 80-MHz offset, while dissipating 65 mW. Using a feedback filtering technique, the circuit introduces a null with an arbitrary width at the receive frequency and eliminates the need for an external SAW filter. A stability analysis is performed to choose the most suitable architecture for the feedback path, which ensures stability over a wide range of loop-gain. Nonideal effects such as quadrature phase and gain errors, LO feedthrough, harmonic downconversion and phase-noise are also analyzed.
Keywords :
CMOS integrated circuits; VHF circuits; code division multiple access; integrated circuit noise; low-power electronics; notch filters; phase noise; radio transmitters; radiofrequency integrated circuits; surface acoustic wave filters; external SAW filter; feedback filtering technique; frequency 80 MHz; integrated notch filter; low-power CMOS WCDMA transmitter; phase-noise; receive-band noise; size 65 nm; stability analysis; Circuit stability; Feedback circuits; Feedback loop; Filtering; Frequency; Multiaccess communication; Noise level; SAW filters; Stability analysis; Transmitters; Feedback; IF frequency translation; SAW filter; WCDMA; local oscillator; mixer; noise; phase-noise; quadrature error; receiver; stability; transmitter;
Journal_Title :
Solid-State Circuits, IEEE Journal of
DOI :
10.1109/JSSC.2008.2005698
