Transmission of wired and wireless signals employing a hybrid radio-over-fibre passive-optical-networkbased on dual quadrupling-frequency

A novel full duplex cost-effective hybrid radio-over-fibre passive-optical-network based on external modulation of a distributed feedback laser diode and dual-drive Mach-Zehnder modulator with multi-wavelength output characteristic is proposed and experimentally demonstrated. Baseband non-return-to-zero (BB-NRZ) signals, radio-frequency NRZ (RF-NRZ) signals, as well as RF orthogonal frequency division multiplexing (RF-OFDM) signals are successfully transmitted simultaneously. After transmission over 50-km of a single-mode fibre, low-bit-error rate and clear eye diagram are achieved for BB-NRZ and RF-NRZ transmission system. The power penalties for BB-NRZ, RF-NRZ and RF-OFDM downstream signals are less than 1-dB. The frequency of local oscillator signal is reduced because of frequency quadrupling scheme. Compared with recent schemes, the cost of the proposed system is largely reduced.