LOOP-BACK SYSTEM USING MACH-ZEHNDER MODULATOR

摘要

PURPOSE: A loop-back system using a Mach-Zehnder modulator is provided to remove an optical source in a BS(Base Station) by receiving the optical source necessary for the BS from a CO(Central Office), modulating the optical source using the Mach-Zehnder modulator, and transmitting the modulated optical source to the CO. CONSTITUTION: A CO-side optical transmitting and receiving unit(300) modulates a downstream data transmission optical wavelength by an RF(Radio Frequency) provided from a CO-side RF transmitting and receiving unit(100), and transmits the modulated downstream data transmission optical wavelength to a BS side through an optical fiber without modulating an upstream data transmission optical wavelength. A BS-side optical transmitting and receiving unit(400) demodulates the downstream data transmission optical wavelength transmitted from the CO-side optical transmitting and receiving unit(300) to an RF signal, modulates the upstream data transmission optical wavelength using a Mach-Zehnder modulator by an RF signal provided from a BS-side transmitting and receiving unit(200), and transmits the modulated upstream data transmission optical wavelength to a CO side.