Telecommunications – Receiver or analog modulated signal frequency converter – Noise or interference elimination
Reexamination Certificate
2006-01-24
2006-01-24
Vo, Nguyen T. (Department: 2685)
Telecommunications
Receiver or analog modulated signal frequency converter
Noise or interference elimination
C455S333000, C333S195000
Reexamination Certificate
active
06990327
ABSTRACT:
A notch filter with a high Q factor, which is integrated with a first and a second cascoded LNA, is totally contained on an integrated chip. The notch filter, comprising two Q-enhancement circuits, is coupled to the second differential LNA. The two Q-enhancement circuits are combined to generate sufficient negative impedance to compensate for the loss in the on-chip low Q inductors. To improve the image rejection of the notch filter in a wide frequency band, the notch filter uses an automatic current tuning circuit which consists of an analog multiplier and fixed and voltage controlled current sources. Furthermore, by modifying the connection and location of the tunable varactor, another wideband tunable notch filter is implemented. The notch filter can be applied in all current wireless receiver systems.
REFERENCES:
patent: 4327332 (1982-04-01), Malchow
patent: 5625307 (1997-04-01), Scheinberg
patent: 5737035 (1998-04-01), Rotzoll
patent: 6072376 (2000-06-01), Matsuyoshi et al.
patent: 6127962 (2000-10-01), Martinson
patent: 6177964 (2001-01-01), Birleson et al.
patent: 6285865 (2001-09-01), Vorenkamp et al.
patent: 6351502 (2002-02-01), Zargari
patent: 6374094 (2002-04-01), Zappala
patent: 6661301 (2003-12-01), Traub
patent: 2001/0008430 (2001-07-01), Carr et al.
patent: 2002/0173287 (2002-11-01), Rogers et al.
patent: 2003/0030393 (2003-02-01), Morishita et al.
J. Crols et al., CMOS Wireless Transceiver Design, Kluwer Academic Publishers, 1997, pp. 13-19, 63-66.
T.H. Lee, The Design of CMOS Radio—Frequency Integrated Circuits, U.K. : Cambridge Univ. Press, 1998, pp. 550-559.
B. Razavi, RF Microelectronics, NJ: Prentice Hall, 1998, pp. 122-129, 138-143.
J. Crols et al., “A Single-Chip 900 MHz CMOS Receiver Front-End with a High Performance Low-IF Topology”, IEEE Journal of Solid State Circuits, vol. 30, No. 12, pp. 1483-1492, Dec. 1995.
Chunbing Guo et al., “A Monolithic 2-V 950-MHz CMOS Bandpass Amplifier With a Notch Filter for Wireless Receivers,” IEEE Radio Frequency Integrated Circuits Symp., 2001, pp. 79-82.
Yuyu Chang et al., “An Inductorless Active Notch Filter for RF Image Rejection,” Proc. IEEE Int. Symp. on Circuits and Systems, 1999, pp. 166-169.
H. Samavati et al., “A 5-GHz CMOS Wireless LAN Receiver Front End,” IEEE Jrnl. of Solid State Circuits, vol. 35, No. 5, May 2000, pp. 765-772.
M.H. Koroglu et al., “LC Notch Fiter for Image—Reject Applications Using On-Chip Inductors,” Electronics Letters, Mar. 1, 2001, vol. 37, No. 5, pp. 267-268.
J. Macedo et al., “A 2.5 GHz Monolithic Silicon Image Reject Filter,” IEEE 1996 Custom Integrated Circuits Conference, pp. 193-196.
J.W.M. Rogers et al., “A Completely Integrated 1.8 Volt 5 GHz Tunable Image Reject Notch Filter,” IEEE Radio Frequency Integrated Circuits Symp., 2001, pp. 75-78.
Wong Sheng Jau
Xu Yong
Zheng Yuanjin
Ackerman Stephen B.
Agency for Science Technology and Research
Le Nhan T.
Saile George O.
Vo Nguyen T.
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