Appeal No. 97-1167 Page 4
Application No. 08/475,062
head, and a decoder for decoding, by a maximum
likelihood decoding method, an equalized reproduced
signal obtained from said equalizer;
said apparatus further comprising:
a distortion detector for measuring a second
harmonic distortion of the reproduced signal;
a decision circuit for making a decision as to
whether or not the second harmonic distortion is -25
dB or lower;
a measuring circuit for measuring a signal-to-
noise ratio of the reproduced signal, and
a bias current control circuit supplied with the
results of both said decision circuit and said
measuring circuit, and controlling the bias current
in said reproducing head in such a manner that the
signal-to-noise ratio becomes highest in a range
where the second harmonic distortion of the
reproduced signal is -25 dB or lower.
The references relied on by the patent examiner in
rejecting the claims follow:
Tin 4,280,153 Jul. 21,
1981
Shimotashiro et al. (Shimotashiro) 5,124,861 Jun.
23, 1992
Ottesen et al. (Ottesen) 5,301,080 Apr.
5, 1994
(filed Dec. 31,
1992).
Claims 3, 11, 13, and 15 stand rejected under 35 U.S.C.
§ 103 as obvious over admitted prior art (Admission) in view
of Ottesen and Shimotashiro. (Final Rejection at 5.) Claims
6, 12, and 14 stand rejected under § 103 as obvious over
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