Title:
FREQUENCY OFFSET ESTIMATOR
Document Type and Number:
Japanese Patent JP3846546
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To estimate a frequency offset even when the ratio of receiving carrier power to noise power is low.
SOLUTION: A complex symbol series 13, i.e., the product of conjugate complexes of a complex demodulation symbol sequence 1 detected through quadrature lection and a known symbol series 2, is provided to phase rotation sections 4a, 4b and 4c, where the phase of the complex symbol series 13 is varied based on frequency offsets fa, fb and fc. N symbol adding sections 5a, 5b and 5c add the values which are inputted from the phase rotating sections 4a, 4b and 4c for N symbols, M power adding sections 6a, 6b and 6c calculate the power of values inputted from the N symbol adding sections 5a, 5b and 5c M number of times. A frequency offset control section 7 controls the frequency offsets being fed to the phase rotation sections 4a, 4b and 4c, based on three power sums inputted from the M power-adding sections 6a, 6b and 6c and outputs an estimated frequency offset value 8.
Inventors:
Takahiro Hisamura
Application Number:
JP2000259029A
Publication Date:
November 15, 2006
Filing Date:
August 29, 2000
Export Citation:
Assignee:
NEC
International Classes:
H04L27/38; H04B1/707; H04B1/7087; H04B3/06; H04L27/00; H04L27/22; H04L27/227; (IPC1-7): H04L27/38; H04B3/06; H04B1/707; H04L27/227; H04L27/22
Domestic Patent References:
| JP9200081A | ||||
| JP8213933A |
Other References:
棚田ほか,広い周波数引き込み範囲を有する1/2シンボル遅延検波型AFCの特性,信学技法,日本,電子情報通信学会,1996年 6月,RCS96-25,1-6
林ほか,時間分散の大きいフェージング伝送路における周波数オフセット推定方式,信学技法,日本,電子情報通信学会,1998年 9月,RCS98-81,13-18
林ほか,時間分散の大きいフェージング伝送路における周波数オフセット推定方式,信学技法,日本,電子情報通信学会,1998年 9月,RCS98-81,13-18
Attorney, Agent or Firm:
Akio Miyazaki
Masaaki Ogata
Ishibashi Masayuki
Masaaki Ogata
Ishibashi Masayuki
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