Method for frame and frequency synchronization of an OFDM signal and method for transmitting an OFDM signal

Patent 7339882 Issued on March 4, 2008. Estimated Expiration Date:

March 15, 2022. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.

Abstract Claims Description Full Text

Patent References

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Inventors

Assignee

Robert Bosch GmbH

Application

No. 10473631 filed on 03/15/2002

US Classes:

370/203, GENERALIZED ORTHOGONAL OR SPECIAL MATHEMATICAL TECHNIQUES370/350, Synchronization375/141, End-to-end transmission system370/208, Particular set of orthogonal functions370/342, Combining or distributing information via code word channels using multiple access techniques (e.g., CDMA)375/295, TRANSMITTERS375/267, Diversity375/260, Plural channels for transmission of a single pulse train375/340Particular pulse demodulator or detector

Examiners

Primary: Yao, Kwang Bin
Assistant: Lai, Andrew

Attorney, Agent or Firm

Kenyon & Kenyon LLP

Foreign Patent References

199 17 337 DE 10/01/2000
0 961 448 EP 12/01/1999
2 758 031 FR 07/01/1998
HU 9902101 HU 10/01/1999
HU 0001298 HU 08/01/2000
7099486 JP 04/01/1995
10210000 JP 08/01/1998
WO 96/02991 WO 02/01/1996
WO99/56424 WO 11/01/1999
WO 9956424 WO 11/01/1999
WO02/078280 WO 10/01/2002

International Class

H04J 11/00

Abstract

A method for frame and frequency synchronization of an OFDM signal and a signal for transmitting an OFDM signal is described, the purpose of which is to impress a pilot phase profile that is then used at the receiving end for frame and frequency synchronization on pilots which are already contained in the OFDM signal for channel estimation. This has the advantage that no additional transmission capacity has to be used for the synchronization. The method according to the present invention is initiated by a rough time synchronization unit connected upline, which searches for the beginning of the guard interval in the OFDM signal. The comparison between a stored pilot phase profile and the received subcarrier symbol is performed using a cross-correlation, whose result is then evaluated to determine the frame and frequency synchronization.

Other References

Stefan Fechtel et al., “Fast Frame Synchronization, Frequency Offset Estimation and Channel Acquisition for Spontaneous Transmission Over Unknown Frequency-Selective Radio Channels,” 1993, pp. 229-233 Aachen University of Technology, IS2, Aachen, Germany.
Keller et al., Orthogonal Frequency Division Multiplex Synchronisation Techniques . . . , IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, Oct. 1996, pp. 963-967.
Fechtel et al., Fast Frame Synchronization, . . . , IEEE International Symposium on Personal, Indoor and Mobile Radio Communications, 1993, pp. 229-233.