Modulation in an optical network

A method of providing communications services, the method comprising:

• receiving a modulated optical signal modulated at a radio frequency and comprising a carrier wavelength and first data;
• splitting the modulated optical signal into a first portion and a second portion;
• converting the second portion of the modulated optical signal into an electrical signal;
• transmitting the electrical signal using a radio frequency transceiver without frequency conversion;
• substantially erasing the first data from the optical signal by performing an inversion operation on the converted second portion of the modulated optical signal;
• receiving second data;
• and
• modulating the carrier wavelength with the second data for onward transmission of the second data, the inversion operation comprising applying a signal comprising an inverse of the first data to the first portion of the modulated optical signal.

A communications network including an apparatus arranged to receive a modulated optical signal modulated at a radio frequency and comprising a carrier wavelength and first data, the apparatus arranged to substantially erase the first data from the optical signal by performing an inversion operation on the modulated optical signal, the apparatus comprising:

• an optical splitter to split the modulated optical signal into a first portion and a second portion,
• a photo detector to convert the second portion of the modulation optical signal into an electrical signal,
• a radio transceiver arranged to transmit the electrical signal without frequency conversion,
• the apparatus further arranged to receive second data and to modulate the carrier wavelength with the second data for onward transmission of the second data, wherein the inversion operation comprises applying a signal comprising an inverse of the first data to the first portion of the modulated optical signal.