Multiplex communications – Communication over free space – Combining or distributing information via time channels
Reexamination Certificate
2011-03-15
2011-03-15
Duong, Frank (Department: 2474)
Multiplex communications
Communication over free space
Combining or distributing information via time channels
Reexamination Certificate
active
07907593
ABSTRACT:
To allow a receiving entity to derive a longer channel estimate while limiting overhead, a transmitting entity transmits a pilot on different groups of subbands in different time intervals. N subbands in the system are arranged into M non-overlapping groups. Each group includes P=N/M subbands that are uniformly distributed across the N subbands. The transmitting entity transmits the pilot on a different subband group in each time interval, and selects all M subband groups in M time intervals based on a pilot staggering pattern. The receiving entity derives (1) an initial impulse response estimate with P channel taps based on the pilot received on one subband group and (2) two longer impulse response estimates with different lengths used for data detection and time tracking. Each longer impulse response estimate may be derived by filtering initial impulse response estimates for a sufficient number of subband groups using a time-domain filter.
REFERENCES:
patent: 5303263 (1994-04-01), Shoji et al.
patent: 5488635 (1996-01-01), Chennakeshu et al.
patent: 5732113 (1998-03-01), Schmidl et al.
patent: 6654428 (2003-11-01), Bose et al.
patent: 6654429 (2003-11-01), Li
patent: 6654728 (2003-11-01), Li et al.
patent: 6684173 (2004-01-01), Kessenich et al.
patent: 6954481 (2005-10-01), Laroia et al.
patent: 7012882 (2006-03-01), Wang et al.
patent: 7020226 (2006-03-01), Kirkland
patent: 7049404 (2006-05-01), Mao et al.
patent: 7139331 (2006-11-01), Kolze
patent: 7180965 (2007-02-01), Eilts et al.
patent: 7200190 (2007-04-01), Malette et al.
patent: 7324606 (2008-01-01), Eilts et al.
patent: 7339999 (2008-03-01), Gore et al.
patent: 7352821 (2008-04-01), Kannan et al.
patent: 2005/0063298 (2005-03-01), Ling et al.
patent: 2005/0135308 (2005-06-01), Vijayan et al.
patent: 2005/0135509 (2005-06-01), Mantravadi et al.
patent: 2005/0163258 (2005-07-01), Gore et al.
patent: 0938208 (1999-08-01), None
patent: 1320232 (2003-06-01), None
patent: 2000068975 (2000-03-01), None
patent: 2002009724 (2002-01-01), None
patent: 2003134086 (2003-05-01), None
patent: 2004007353 (2004-01-01), None
patent: WO9800946 (1998-01-01), None
Mostofi, Y, et al.: “Effect of Frame Synchronization Errors on Pilot-Aided Channel Estimation in OFDM: Analysis and Solution” Wireless personal Multimedia Communications, 2002. The 5th International Symposium on Oct. 27-30, 2002, Piscataway, NJ, USA, IEEE.
Sandell, et al: “A Comparative Study of Pilot-Based Channel Estimators for Wireless OFDM” Research Report Tulea, Division of Signal Processing, No. 19, Sep. 1, 1996.
International Search Report—PCT/US05/014259, International Search Authority—European Patent Office, Aug. 1, 2005.
International Preliminary Report on Patentability, PCT/US2005/014259, The International Bureau of WIPO Nov. 7, 2006.
Written Opinion PCT/US2005/014259, International Search Authority Europeoan Patent Office, Apr. 11, 2006.
European Standard (Telecommunications series), “Digital Video Broadcasting (DVB); Framing structure, channel coding and modulation for digital terrestrial television”, ETSI EN 300 744 v1.4.1 (Jan. 2001), section 4.5.3.
Dukhyun Kim et al.: “Residual ISI Cancellation for OFDM with Applications to HDTV Broadcasting,” Oct. 1998; XP002159671.
Hunter et al., “Channel Estimation for Mobile OFDM Systems,” IEEE, Vehicular Technology Conference, 1:305-309 (Sep. 19, 1999).
Ryu et al.: “Comparison of two FFT structures for Fractionally-spaced frequency domain Equalizer,” pp. 1710-1713 May 6, 2002.
Mantravadi Ashok
Mukkavilli Krishna Kiran
Vijayan Rajiv
Braden Stanton
Duong Frank
Qualcomm Incorporated
Zhu Peng
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