The present disclosure relates to an improvement in the quality of a transmitted signal, and more particularly, to an electronic apparatus and a method which are provided with a passive equalizer improving the quality of a transmitted signal when a signal is transmitted/received to/from an external apparatus, and a system for the same. The present disclosure provides a signal transmission system for improving the quality of a transmitted signal. The signal transmission system may include a transmitter that transmits a signal; a receiver that receives the signal from the transmitter; a channel that is formed between the transmitter and the receiver and transmits the signal delivered by the transmitter; and a passive equalizer that is formed between the transmitter and the receiver and controls the signal so as to have a higher impedence than a predetermined impedance at a lower frequency than a predetermined frequency of the signal.