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Abstract: We proposed and simulatedly demonstrated a novel full-duplex radio-over-fiber system using an external modulator and an optical interleaver to generate dual quadrupling-frequency optical millimeter waves for carrying two base station downstream data and wavelength reuse for uplink connection. The simulation results reveal that the power penalties for the downstream and upstream signals of both base stations are less than 0.8dB. In this new scheme, the configuration of the both base stations is simplified further because there is no additional laser at two base stations. The frequency of local oscillator signal is reduced due to frequency quadrupling. The cost of the new system is largely reduced. [Copyright &y& Elsevier]

Abstract: All-optical broadband variable optical attenuators (VOAs) and switches based on plasmonic teeth shaped waveguides have been proposed and numerically investigated. The Finite Difference Time Domain (FDTD) simulation results reveal that VOAs based on three teeth structure filled with CdSe-doped PMMA can continuously attenuate the power of a light beam from 3.7dB to 39dB within a broad forbidden band by an external control light. For wavelengths within the forbidden band, the structure can also operate as a switch with presence or absence of pumping light corresponding to on or off state. For a modulation depth of 27dB, a relatively small variation in the absorption coefficient of CdSe QD-PMMA in side cavity (from κ= 0 to κ= 0.15) is enough. [Copyright &y& Elsevier]

Abstract: We propose a novel radio-over-fiber system based on double-sideband (DSB) modulation and frequency quadrupling to reduce the system cost both at central office (CO) and base station (BS). In this system, by properly biasing the intensity modulator, the repetitive frequency of the optical millimeter-wave (mm-wave) is four times frequency of the local oscillator (LO) signal. Additionally, due to the single-sideband of the mm-wave carrying base data signal, our theoretical simulation shows that the generated mm-wave can be immunized the fading effect and the walk-off of signals. [Copyright &y& Elsevier]