Detecting method and detecting circuit thereof

Application Number: 00108953
Application Date: 2000.05.23
Publication Number: 1274999
Publication Date: 2000.11.29
Priority Information: 1999/5/24 JP 144024/99
International: H04B1/707;H04J13/04
Applicant(s) Name: Ricoh Co., Ltd.
Inventor(s) Name: Takahashi Soichi;Michikichi Kei
Patent Agency Code: 11105
Patent Agent: yang wu
Abstract To improve the demodulation characteristic over that of a simple pilot symbol detection system by estimating up to a fluctuation component of a transfer function. A pilot symbol generating circuit 10 and a multiplier 11 calculate a transfer function (h) of a received signal for a time period when the received signal is a pilot symbol. Application of this calculation to an optional number of or all of pilot symbols within a time period of the pilot symbols obtains a plurality of transfer functions h1-hn. An approximate curve estimate circuit 13 estimates a parameter of an approximate curve on the basis of a plurality of the transfer functions obtained as above to acquire an estimate value of the transfer function, a fluctuation speed of the transfer function and a fluctuation acceleration of the transfer function. Thus, the estimation of the transfer functions can include the effect of the fluctuation speed and the fluctuation acceleration of the transfer functions.