Title :
A low power fully integrated analog baseband circuit with variable bandwidth for 802.11 a/b/g WLAN
Author :
Liu, Kai-Yin ; Chen, Chun-Hao ; Yang, Yu-Che ; Chen, Hsiao-Chin ; Yu, Shih-An ; Lu, Shey-Shi
Author_Institution :
Graduate Inst. of Electr. Eng., National Taiwan Univ., Taipei, Taiwan
Abstract :
This paper presents experimental results of an analog baseband circuit with variable bandwidth for WLAN direct conversion receiver in UMC 0.18μm CMOS process. A seventh order Chebyshev lowpass filter with triple bandwidth is used in the analog baseband circuit. The bandwidth is selectable from 7.56MHz, 19.5MHz, or 26.5MHz. The circuit adopts the servo loop for dc offset cancellation. It also has a gain range from 20dB to 60 dB with 10 dB steps while only dissipating 22.248mW. In addition, an automatic frequency tuning loop (ATL) is reported to achieve the bandwidth accuracy of the filter.
Keywords :
CMOS analogue integrated circuits; Chebyshev filters; circuit tuning; low-pass filters; low-power electronics; receivers; wireless LAN; 0.18 micron; 19.5 MHz; 20 to 60 dB; 22.248 mW; 26.5 MHz; 7.56 MHz; 802.11 WLAN standard; CMOS process; WLAN direct conversion receiver; automatic frequency tuning loop; dc offset cancellation; low power integrated analog baseband circuit; servo loop; seventh order Chebyshev lowpass filter; variable bandwidth; Automatic frequency control; Bandwidth; Baseband; CMOS process; Chebyshev approximation; Circuit optimization; Filters; Servomechanisms; Tuning; Wireless LAN; WLAN; chebyshev; lowpass filter; tuning;
Conference_Titel :
Microwave Conference Proceedings, 2005. APMC 2005. Asia-Pacific Conference Proceedings
Print_ISBN :
0-7803-9433-X
DOI :
10.1109/APMC.2005.1606465
