OPTICAL SIGNAL QUALITY EVALUATION METHOD AND OPTICAL SIGNAL QUALITY EVALUATION DEVICE AND RECORDING MEDIA

Japanese Patent JP3504902

B2

PROBLEM TO BE SOLVED: To improve quality evaluation accuracy with a single circuit, regardless of bit rate of measured signal, signal form or modulation form.
SOLUTION: A signal process unit 1503 has a strength distribution estimation part 1505, which estimates axial symmetric points group (a-2) about threshold A from points group (a-1) with a strength higher than the strength threshold A and each (a-1), (a-2) points group makes to level '1', and also estimates axial symmetric points group (b-2) about threshold B fun points group (b-1) with a strength lower than the strength threshold B which is decided separate by, then each (b-1), (b-2) points group makes to level '0' among sampling points in signal strength distribution obtained with a sampling oscilloscope 1502 and It also has a light signal quality evaluation part 1506 for evaluating a signal to noise ration coefficient obtained as the ration of the difference between the average strengths of level '1' and level '0' obtained from the strength distribution in a certain averaging time and the sum of the standard deviation values of level '1' and level '0' in the averaging time.

Shake Ippei
Hidehiko Kora
Yoshiaki Yamabayashi
Kouichi Fujisaki

JP2000012240A

March 08, 2004

January 20, 2000

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Nippon Telegraph and Telephone Corporation
NTT Electronics Corporation

G01R13/40; G01J11/00; H04B10/07; H04B10/079; H04B10/29; H04B10/524; H04B10/564; H04B10/58; H04J3/00; H04L25/02; (IPC1-7): G01J11/00; G01R13/40; H04B10/08; H04J3/00; H04L25/02

JP2001194267A

Ｉ．Ｓｈａｋｅ 他３名，Ｏｐｔｉｃａｌ ｓｉｇｎａｌ ｑｕａｌｉｔｙ ｍｏｎｉｔｏｒｉｎｇ ｍｅｔｈｏｄ ｂａｓｅｄ ｏｎ ｏｐｔｉｃａｌ ｓａｍｐｌｉｎｇ，ＥＬＥＣＴＲＯＮＩＣＳ ＬＥＴＴＥＲＳ，１９９８年１０月２９日，Ｖｏｌ．３， Ｎｏ．２２，ｐｐ．２１５２−２１５４

Yoshikazu Tani (1 person outside)

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