DUPLEX MODEM Russian patent published in 2000 - IPC

FIELD: telecommunications, in particular, data transmission systems that provide duplex communication through two-wire telephone lines. SUBSTANCE: device has encoder, modulator, output unit of transmitter, differential circuit, input unit, test signal generator, control unit, echo compensation unit, harmonic frequency detector, automatic signal corrector, demodulator, decoder, switch, delay line, subtraction unit, carrier evaluation unit, two mean calculation units, units for calculation of channel amplitude- frequency response, channel complex frequency response, channel group delay, matched and correction filters, input unit of receiver. EFFECT: increased reliability and increased speed of establishing connection. 6 dwg