Multiplex communications – Generalized orthogonal or special mathematical techniques – Particular set of orthogonal functions
Patent
1997-07-25
2000-09-19
Vu, Huy D.
Multiplex communications
Generalized orthogonal or special mathematical techniques
Particular set of orthogonal functions
370206, 370491, H04M 1106, H04B 310
Patent
active
061222461
ABSTRACT:
A multi-point communications system is set forth herein. The communications system comprises a transmitter for transmitting OFDM/DMT symbols over a predetermined number of bins across a transmission medium. The OFDM/DMT symbols are generated using at least one timing signal. At least one of the predetermined number of bins includes a pilot tone sub-symbol having a frequency corresponding to the clock signal. The communications system also includes a receiver for receiving the OFDM/DMT symbols from the transmission medium. The receiver demodulates the received symbols using at least one timing signal. The receiver has a first pilot tone search mode of operation in which the receiver adjusts its timing signal to scan the frequency range of the predetermined number of bins looking for the pilot tone sub-symbol and identifies the bin including the pilot tone sub-symbol. The receiver further has a subsequent second pilot tone acquisition mode in which the receiver adjusts the timing signal to receive the identified bin containing the pilot tone sub-symbol and measures phase differences between successive pilot tone sub-symbols to thereby perform a further adjustment of the timing signal so that the pilot tone sub-symbol is received within a frequency range sufficient for subsequent phase locked loop processing thereof.
REFERENCES:
patent: 5471464 (1995-11-01), Ikeda
patent: 5557612 (1996-09-01), Bingham
patent: 5596582 (1997-01-01), Sato et al.
patent: 5610908 (1997-03-01), Shelswell et al.
patent: 5682376 (1997-10-01), Hayashino et al.
patent: 5774450 (1998-06-01), Harada et al.
patent: 5812523 (1998-09-01), Isaksson et al.
"A Technique for Orthogonal Frequency Division Multiplexing Frequency Offset Correction", IEEE Transactions On Communications, vol. 42, No. 10, Oct. 1994.
Chandran Ravi
Kapoor Samir
Marchok Daniel J.
Phan M.
Tellabs Operations Inc.
Vu Huy D.
LandOfFree
Apparatus and method for clock synchronization in a multi-point 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 method for clock synchronization in a multi-point , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus and method for clock synchronization in a multi-point will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1080345