| 摘要 |
PURPOSE:To correct automatically a fixed type amplitude equalizer by checking the converging state of an MODEM, changing the amount of correction of the amplitude equalizer when the state is kept diffusive and also requesting the retraining to the transmission side. CONSTITUTION:A discrimination circuit 15 checks the output state of a reception signal quality discriminating circuit 11-1 and when the MODEM is in the non- converging state, the circuit 15 increases the amount of equalization of an amplitude equalizer 10-1 by one step and also allows a retraining control circuit to transmit a retraining transmission request signal to a transmission station 20. When an output is transmitted from a timer 14 to the discriminating circuit 15 further, the discrimination circuit 15 discriminates again an output of the quality discrimination circuit 11-1 and when the MODEM still keeps the non-converging state, the circuit 15 increases further the amount of equalization by one step to allow the circuit 16 to transmit the retraining transmission request signal again. This action is repeated until the MODEM is brought to the converging state thereby attaining a proper correcting amount. |
