Pulse or digital communications – Systems using alternating or pulsating current – Plural channels for transmission of a single pulse train
Reexamination Certificate
2006-06-07
2009-12-08
Fan, Chieh M (Department: 2611)
Pulse or digital communications
Systems using alternating or pulsating current
Plural channels for transmission of a single pulse train
Reexamination Certificate
active
07630450
ABSTRACT:
The channel estimation technique employs a set of pilot tones to determine channel state information. Because some of the pilot tones contained in the OFDM symbols may be missing after transmission, the disclosed technique employs a set of known pilot tones to compute an estimate of the channel impulse response, which may exhibit a level of distortion. Non-zero terms of the estimated channel impulse response that fall outside of a prescribed time window are regarded as artifacts of a set of missing or unknown pilot tones. Information relating to the known pilot tones and the artifacts of the unknown pilot tones are employed for mathematically reconstructing and deriving values of the unknown tones. Then, the values of the known pilot tones and the derived values of the unknown pilot tones are employed to recompute the channel impulse response, thereby obtaining the channel estimate with a reduced level of distortion.
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Jukka Rinne, Ali Hazmi and Markku Renfors, “Impulse Burst Position Detection and Channel Estimation Schemes for OFDM Systems”, Tampere University, Finland and Nokia, Jun. 19, 2003, IEEE.
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Ove Edfors, et al. “OFDM Channel Estimation by Singular Value Decomposition” IEEE Transactions on Communications, IEEE Service Center, Piscataway, NJ; vol. 46, No. 7, July 1998; XP011009204, ISSN:0090-6778, Figure 3.
PCT Search Report Dated Oct. 4, 2006; copy inadvertently not included with IDS/RCE filed Jun. 8, 2009.
Curtis Anthony P.
Fan Chieh M
Fotakis Aristocratis
Motorola Inc.
Pace Lalita W.
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