Application of an electroabsorption modulator in radio-over-fiber networks [Invited]

A 60⁢ GHz radio-over-fiber (RoF) network using an electroabsorption modulator (EAM) is presented. A photonic frequency upconversion technique that utilizes the wavelength conversion process in the EAM is adopted for seamless integration of optical and wireless networks. The transmission characteristics of the quadrature amplitude modulation (QAM) coded data signal over the 60⁢ GHz photonic-wireless link, which comprises the 50⁢ km optical fiber transmission between the central station and the base station (BS) and the aerial transmission between the BS and the customer unit using horn antennas, are investigated by measuring the error vector magnitude (EVM) and its dependence on the EAM bias voltage. Optimized EVM values of 3.8% and 3.9% are obtained for 64-QAM and 16-QAM at an EAM bias of −0.8 V, respectively.