| 摘要 |
PURPOSE:To provide the equalizer which sufficiently follows up the quick variance of a transmission line by inserting a tap coefficient variation estimating circuit between an amplifier and an accumulator and estimating the variation of the tap coefficient. CONSTITUTION:Signals on taps taken out from plural delay elements connected in series to a transversal filter are inputted to an input terminal 101, and the difference between the output of the transversal filter and a reference signal like the output of a symbol discriminator is inputted to a second input terminal 102. A multiplier 103 multiplies the input signal from taps and the difference signal, and the output of the multiplier 103 is amplified mu1 times by an amplifier 104. The output is amplified mu2 times by an amplifier 106 and is accumulated in an accumulator 107 to obtain the accumulated value of the signal before a time jT. This accumulated value and the signal from the amplifier 104 are added by an adder 110, and the difference between the present signal and the past signal, namely, the variation is inputted to an accumulator 111. The accumulator 111 corrects the tap coefficient estimated value by this variation and outputs the obtained value as the next tap coefficient estimated value. |
