A line equalizer having a function of selecting a critical region

摘要

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line equalizer applied to a digital data transmission apparatus having a digital data service network, in which a receiving low pass filter, a receiving equalizer, and a double / A signal loss detector 8 connected to receive the input and output signals of the receiving equalizer 6 in a digital data transmission apparatus constituted by a transmitting end in which a unipolar / double polarity encoder, a waveform shaping device and a line driver are sequentially connected,; A path controller (9) connected to receive a user input and an output signal of the signal loss detection (8); A waveform shaping device 20, a transmission amplifier 3 connected between the line driver 4, Two switches SW1 and SW2 connected to the transmission amplifier 3 and the line driver 4 and connected to the waveform shaping device 2 and the line driver 4 and capable of determining the transmission path by on / If a signal having a loss equal to or greater than the critical area can be selected by the user input ADNSEL with respect to the reception signal having a loss equal to or greater than the critical area, So that the equalizing capability can be improved in the subsequent receiver.