Apparatus and methods for digital-to-analog conversion

Details Apparatus and methods for digital-to-analog conversion Apparatus and methods for digital-to-analog conversion

2006-04-18

2006-04-18

Kim, Kevin (Department: 2638)

Pulse or digital communications

Pulse code modulation

Differential

C341S134000

Reexamination Certificate

active

07031395

ABSTRACT:
An apparatus for converting a digital input signal to an analog signal for transmission. The input signal can include more than one carrier signal. A plurality of delta-sigma modulation loop circuits are connected in an increasing order of operating frequency so as to reduce a word length of the input signal. A tuning circuit adjusts the signal frequency to a transmitting frequency for conversion to analog by a digital-to-analog converter. A first loop circuit is implemented using CMOS gates, and a second loop circuit and the tuning circuit are implemented using indium phosphide gates. The apparatus allows a high-resolution, wide-band RF multiple-carrier signal to be re-quantized to a lower-resolution signal while an acceptable signal-to-noise ratio is maintained.

REFERENCES:
patent: 6144328 (2000-11-01), Eastty et al.
patent: 6339621 (2002-01-01), Cojocaru et al.
Splett A. et al, “Solutions for highly integrated future generation software radio basestation transceivers”; Proceedings of the IEEE 2001 Custom Integrated Circuits Conference, (CICC 2001), San Diego, CA, May 6-9, 2001, IEEE Custom Integrated Circuits Conference, CICC, New York, NY; IEEE, US, vol. Conf. 23, May 6, 2001, pp. 511-518.
Efstathiou D, “SoftCell TM/: A Multi-Carrier Transceiver Solution for Multi-Mode Base-Stations”, 11thIEEE International Symposium on Personal Indoor and Mobile Radio Communications, PIMRC 2000. Proceedings (Cat. No. 00TH8525), Proceedings of 11thInternational Symposium on Personal, Indoor and Mobile Radio Communication, London, UK, Sep. 18-21, pp. 469-473 vol. 1.
Bindra A, “Wideband DAC Fosters Multicarrier, Multimode Transmission Novel 150-Msample/s, 14-BIT Segmented-current-source DAC boasts 75-DB SFDR over 25 MHZ cellular bandwith” Electronic Design, Pwnron Publishing, Cleveland, OH, vol. 47, No. 12, Jun. 14, 1999, pp. 37-38, 40.
Jensen, J.F. et al, “A 3.2-GHz Second-Order Delta-Sigma Modulator Implemented in InP HBT Technology”, IEEE Journal of Solid-State Circuits, IEEE Inc. New York, vol. 30, No. 10, Oct. 1, 1995, pp. 1119-1127.
Vankka, J. et al, “A Multicarrier QAM Modulator”, IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing, IEEE Inc., New York, NY, vol. 47, No. 1, Jan. 2000, pp. 1-10.
Communication from European counterpart application No. 03 006 234.3.

Affiliated with

Also associated with

Rating

Apparatus and methods for digital-to-analog conversion does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus and methods for digital-to-analog conversion, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and methods for digital-to-analog conversion will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-3525251