OPTICAL FIBRE NETWORK FOR RADIO FREQUENCY AND MICROWAVE SIGNAL DISTRIBUTION

摘要

Apparatus for the distribution of communications signals of radio or microwave frequency to a plurality of receiving units (10). The apparatus comprises a first optical modulator (2) configured to receive an electrical communications signal of radio or microwave frequency and to generate a downstream optical signal modulated by the communications signal. A plurality of receiving units (10) are configured to receive and demodulate the downstream optical signal to generate an electrical signal corresponding to the communications signal. An optical distribution network (3, 4, 5) is arranged to distribute the downstream optical signal from the first optical modulator (2) to the receiving units (10). Each receiving unit comprises a second optical modulator (18) arranged to modulate light received from the optical network with a data signal to generate an upstream optical signal and to return the upstream optical signal to the optical distribution network for onward communication. The apparatus has the advantage that it provides a return communication path from the receiving units (10) that use the same optical network as the downstream optical signal without requiring a separate laser source at each receiving unit (10).