Research on Deeply Converged Communication System Based on Photonic-RF Wave via High Order Frequency-Beating

A novel architecture of communication system is proposed based on a deep integration of wireless and optical fiber system using high-frequency microwave generated by the photonic radio-frequency (RF) processing. It is theoretically demonstrated that only the odd spectral side-bands carry the modulation information, but the even ones do not, and that there is no second order spectral side-band in the output of the spectral side-bands. After the modulated optical signals are transmitted to the base station (BS), the central spectral side-band is used as the laser source of the downlink transmission, the lower one of the fourth spectral side-bands is used as the laser source of the uplink transmission, and the photonic RF wave is generated by the frequency-beating between the upper one and lower one of the third spectral side-bands. The clear eye-diagram and the low bit error rate (BER) are obtained respectively via the professional simulation software under the condition that the signals are transmitted over the standard single mode fiber (SSMF) with 25 km. In the system architecture, there is no laser source in the BS, so the complexity of the BS is reduced greatly. Moreover, owing to the high-frequency microwave produced by photonic-RF wave directly via high order frequency-beating, the RF processing unit is enormously simplified.