Pulse or digital communications – Receivers – Interference or noise reduction
Reexamination Certificate
2005-01-12
2008-11-18
Ha, Dac V (Department: 2611)
Pulse or digital communications
Receivers
Interference or noise reduction
C375S144000
Reexamination Certificate
active
07453966
ABSTRACT:
In one aspect thereof this invention provides a method to increase data throughput in an Orthogonal Frequency Division Multiplex (OFDM) wireless communications system. The method includes modeling data throughput as a function of received Signal to Noise Ratio (SNR) with a sigmoid function to produce a throughput curve characterized as having a lower knee region and an upper knee region; and performing a gradient ascent search along the throughput curve by varying the power of a plurality of sub-carriers so as to remove power from any sub-carrier having a received SNR to the left of the lower knee region, and to re-allocate the removed power to sub-carriers having a received SNR to the right of the lower knee region.
REFERENCES:
patent: 2004/0141548 (2004-07-01), Shattil
patent: 2005/0032476 (2005-02-01), Chae et al.
“Power Allocation for Multi-band OFDM UWB Communication Networks”, Zhengyuan Xu et al., IEEE 2004, pp. 368-372.
“Multiple Users Adaptive Modulation Schemes for MC-CDMA”, Clive Tang et al., IEEE 2004, pp. 3823-3827.
“Adaptive Turbo Coded Modulation for OFDM Transmissions”, Xiaoming She et al., Proceedings of ICCT 2003, pp. 1491-1495.
“Adaptive Modulatin Techniques for Duplex OFDM Transmission”, Thomas Keller et al., IEEE Transactions On Vehicular Technology, vol. 49, No. 5, Sep. 2000, pp. 1893-1906.
“Network-assisted link-adaptation with power control and channel re-assignment in wireless networks”, Dilip Krishnaswamy, Cellular Communications Division, Intel Corporation, 6 pages, 2002.
“Computationally Efficient Optimal Power Allocation Algorithms for Multicarrier Communication Systems”, Brian S. Krongold, et al., IEEE Transactions On Communications, vol. 48, No. 1, 2000, pp. 23-27.
“Adaptive Bit And Power Allocation With Adaptive Transmit Diversity For Broadband MISO/OFDM Wireless Transmission”, Qiu Yong-hong et al., IEEE Int. Conf. Neural Networks & Signal Processing, Dec. 2003, pp. 1472-1476.
“Constant Rate Adaptive Modulation with Selection Transmit Diversity for Broadband OFDM Systems”, Yonghong Qiu et al., IEEE 2003 International Symposium on Person, Indoor and Mobile Radio Communication Proceedings, pp. 722-726.
“Subcarrier Allocation and Power Control for OFDMA”, Didem Kivanc et al., IEEE 2000, pp. 147-151.
“A Modified Sub-Optimum Adaptive Bit and Power Allocation Algorithm in Wideband OFDM System”, Li Zhen et al., IEEE 2003, pp. 1589-1592.
“Peak-to-Average Power Radio Suppression Schemes in DFT Based OFDM”, Young-Seo Park et al., IEEE 2000, pp. 292-297.
Stolpman Victor J.
Tang Clive K.
Ha Dac V
Harrington & Smith PC
Nokia Corporation
LandOfFree
Gradient based method and apparatus for OFDM sub-carrier... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Gradient based method and apparatus for OFDM sub-carrier..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Gradient based method and apparatus for OFDM sub-carrier... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-4042783