| 摘要 |
PURPOSE:To prevent an automatic equalizer from excessive correction and system dispersion by compressing the quantity of an error when the change of the mean value of amplitude from one time slot before exceeds a prescribed value and sending the compressed value to a correcting means. CONSTITUTION:Instantaneous amplitude change generated in an output from an averaging circuit 7 by an impulse noise or the like of a transmission line is inputted to a detecting circuit 8. Said change is compared with the mean value of the preceding time slot, and when the change exceeds a previously fixed value, a decision circuit 9 decides the generation of amplitude disturbance and outputs a decision signal of ''1''. A control signal generating circuit 10 generates a control signal of ''0'' for a fixed period and a selecting circuit 11 selects the output of a subtractor 12 during said period. An excessive error from a discriminator 6 is contracted and compressed by a previously fixed compression factor and the compressed value is supplied to a correcting circuit 4. An equivalent correcting value from a register 2 prevents abnormal correction due to the excessive error. |
