Design Of Cost-Effective Broadband Analog Optical Transceiver And Radio Over Fiber System Application

Radio over Fiber system has combined the high bandwidth and low loss of optical fiber communication with the flexibility of wireless communication, will be an effective broadband wireless access solution in the future. The performance and cost of RoF system were determined by the optical transceivers; therefore the design of cost-effective broadband analog optical transceiver was very significant in the application of radio over fiber systems.In this paper, we completed the design and evaluation of a cost-effective broadband analog optical transceiver based on the commercial off the shelf1310nm lOGbps transmitter optical subassembly and receiver optical subassembly with operating bandwidth up to11GHz, and finished the design and evaluation of a multi-wavelength optical transmitter which aimed at wavelength division multiplexing RoF system application at the same time.Finally, we worked out the demonstration and analysis of multi-service radio over fiber transmission based on the transceivers designed above.This design of transceiver mainly included the design of the laser driver and Bias-Tee circuit, the broadband impedance matching network for the laser modulation and detection, the broadband low-noise, high linearity RF amplifier for link gain compensation and the printed circuit board design. The main indicator of RoF system about gain, bandwidth, noise figure and spurious-free dynamic range were used to evaluate the performance of this optical transceiver. The bandwidth of this transceiver was measured greater than6GHz, link conversion loss less than-40dB, noise figure less than20dB, spurious-free dynamic range greater than85dB/Hz3/2. The design of multi-wavelength optical transmitter mainly consisted of channel independence design and consistency design; adjacent channel crosstalk can be used to evaluate the performance of design. At last, the transmission and analysis of the54Mbps64quadrature amplitude modulation vector signal with orthogonal frequency division modulation were worked out above this system respectively with subcarrier multiplexing and wavelength division multiplexing method.