Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
2003-08-06
2009-06-23
Tse, Young T. (Department: 2611)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
C370S210000
Reexamination Certificate
active
07551677
ABSTRACT:
A pilot phase tracking loop for an OFDM receiver including a phase rotator receiving an incoming signal, a fast Fourier transform coupled to a phase rotator output, and a pilot phase error metric including a discrete Fourier transform portion coupled to the phase rotator output. The pilot phase error metric determines a phase error estimate associated with a received OFDM symbol, e.g., a data symbol, from the phase rotator output. A loop filter is coupled to the pilot phase error metric output and an oscillator is coupled to the loop filter output. The oscillator output is coupled to the phase rotator to adjust the phase of subsequent OFDM symbols of the incoming signal. Phase noise introduced by a radio portion of the OFDM receiver and OFDM transmitter is reduced by the baseband portion of the OFDM receiver improving OFDM signal tracking under poor SNR conditions.
REFERENCES:
patent: 5170415 (1992-12-01), Yoshida et al.
patent: 5577072 (1996-11-01), Moon et al.
patent: 5799047 (1998-08-01), Dobrica
patent: 5930305 (1999-07-01), Leib
patent: 5940450 (1999-08-01), Koslov et al.
patent: 6035003 (2000-03-01), Park et al.
patent: 6181258 (2001-01-01), Summers et al.
patent: 6218896 (2001-04-01), Becker et al.
patent: 6310926 (2001-10-01), Tore
patent: 6370188 (2002-04-01), Wu et al.
patent: 6470030 (2002-10-01), Park et al.
patent: 6549561 (2003-04-01), Crawford
patent: 6549583 (2003-04-01), Crawford
patent: 6891792 (2005-05-01), Cimini et al.
patent: 7061997 (2006-06-01), Eberlein et al.
patent: 2003/0026371 (2003-02-01), Laroia et al.
patent: 0822682 (1998-02-01), None
European Telecommunications Standards Institute 2000 (ETSI); “Broadband Radio Access Networks (BRAN): Hiperlan Type 2; Physical (PHY) Layer”: Technical Specifications; http://www.etsi.org: pp. 1-40; ETSI TS 101 475 V1.1.1 (Apr. 2000).
IEEE Computer Society; “Draft Supplement to Standard [for] Information Technology-Telecommunications and Information Exchange Between Systems-Local and Metropolitan Area Networks-Specific Requirements-Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications: High Speed Physical Layer in the 5 Ghz Band”; IEEE P802 11a/D7.0; Supplement to IEEE Standard 802.Nov. 1999; (1999); pp. 1-90.
Baoguo Yang, et al., “Timing Recovery for OFDM Transmission”. IEEE JOurnal of Selected Areas in Communications, Nov. 2000, pp. 2278-2291, vol. 18, No. 11, IEEE.
Jihoon Choi, et al., “Carrier Frequency Offset Compensation for Uplink of OFDM-FDMA Systems”, IEEE Communications Letters, Dec. 2000, pp. 414-416, vol. 4, No. 12, IEEE.
Dusan Matic, et al., “OFDM Synchronisation Based on the PHase Rotation of Sub-Carriers,” IEEE JOurnal, 2000, pp. 1260-1264, IEEE.
Stefan A. Fechtel, “Performance of OFDM Carrier and Sampling Frequency Synchronization on Stationary and Mobile Channels”, International Conf. on Consumer Electronics 2000, IEEE Journal, Jun. 13-15, 2000, pp. 18-19, IEEE.
Hyoung-Kyu Song, et al., “Frequency-Offset Synchronization and Channel Estimation for OFDM-Based Transmission,” IEEE Communications Letters, Mar. 2000, pp. 95-97, vol. 4, No. 3, IEEE.
Sebastian Simoens, et al. “A New Method for Joint Cancellation of Clock and Carrier Frequency Offsets in OFDM Receivers over Frequency Selective Channels”, Center de Recherche Motorola Paris, Espace Technologique Saint-Aubin 99193, Gif-sur Yvette France, pp. 390-394, IEEE VTC2000, IEEE.
Fred Daneshgaran, et al., “ML Symbol Synchronization for Multichannel Modulation: Analysis and Implementation”, ECE Department, California State University, Los Angeles, pp. 1-5.
Timothy M. Schmidl, et al., “Robust Frequency and Timing Synchronization for OFDM”, IEEE Transactions on Communications, Dec. 1997, pp. 1613-1621, vol. 45, No. 12, IEEE.
Hui Liu, et al., “A High-Efficiency Carrier Estimator for OFDM Communications,” IEEE Communications Letters, Apr. 1998, vol. 2, No. 4, pp. 104-106, IEEE.
Paul H. Moose, “A Technique for Orthogonal Frequency Divisional Multiplexing Frequency Offset Correction,” IEEE Transactions on Communications, Oct. 1994, vol. 42, No. 10, pp. 2908-2914, IEEE.
Paul Koufalas, “State Variable Approach to Carrier Phase Recovery and Fine Automatic Gain Control on Flat Fading Channels,” Aug. 30, 1996, Submitted to the School of Physics and Electronic Systems Engineering of the Faculty of Information Technology of the University of South Australia for the Degree of Master of Electronic Engineering by Research, University of South Australia.
Connolly Bove & Lodge & Hutz LLP
Tse Young T.
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