Optical line terminal, passive optical network and radio frequency signal transmission method

A passive optical network, comprising an optical line terminal (OLT), an optical distribution network (ODN) and, at least one optical network unit (ONU), configured to implement a method comprising:

• in the downstream direction:
• modulating a downstream radio frequency signal to be transmitted to each optical network unit (ONU) on a downstream optical carrier dedicated for the ONU, combining the modulated downstream optical carrier for the ONU and two upstream optical carriers dedicated for the ONU, multiplexing each combined downstream optical signal for each wavelength division ONU, and transmitting the multiplexed optical signal to the ONU via an optical distribution network (ODN), by an optical line terminal (OLT);
• wherein the two upstream optical carriers dedicated for the ONU carry upstream radio frequency signals of the ONU;
• in the upstream direction:
• receiving the wavelength division multiplexed upstream optical wave of each ONU which is transmitted from an ODN, and demultiplexing the multiplexed upstream optical wavelength division wave, and obtaining the upstream signal from each demultiplexed upstream optical signal, by an OLT.

A radio frequency signal transmission method, comprising:

• in the downstream direction:
• modulating a downstream radio frequency signal to be transmitted to each optical network unit (ONU) on a downstream optical carrier dedicated for the ONU, combining the modulated downstream optical carrier for the ONU and two upstream optical carriers dedicated for the ONU, multiplexing each combined downstream optical signal for each wavelength division ONU, and transmitting the multiplexed optical signal to the ONU via an optical distribution network (ODN), by an optical line terminal (OLT);
• wherein the two upstream optical carriers dedicated for the ONU carry upstream radio frequency signals of the ONU;
• in the upstream direction:
• receiving the wavelength division multiplexed upstream optical wave of each ONU which is transmitted from an ODN, and demultiplexing the multiplexed upstream optical wavelength division wave, and obtaining the upstream signal from each demultiplexed upstream optical signal, by an OLT.