Research On Multi-dimensional High-efficiency Radio-over-fiber System Based On Multi-core Fiber

With the development of new technology of smart city,virtual reality and augmented reality,the demand of data traffic is increasing.The high CPRI interface rate of wireless fronthaul in C-RAN architecture limits the development of B5G/6G system.Compared with digital transmission technology,analog Radio-over-Fiber(RoF)technology does not need sampling and quantization,which can effectively solve the problem of excessive bandwidth of fronthaul transmission interface.Conventional RoF array architecture has high cost and low capacity,which is not enough to meet the demand of large-scale wireless communication system for large bandwidth and ultra-high capacity.In response to these challenges,this paper studies a new generation of RoF array system architecture based on multi-core fiber(MCF)transmission.The specific research content and innovations of this paper are as follows:This paper adopts domestic 7-core fiber to construct a new generation of fiber-wireless hybrid RoF transmission system based on MCF space division multiplexing(SDM).Through the transmission of multi-standard wireless signals,the communication quality of the system is analyzed from both EVM and dynamic range.Experimental results show that in MCF-only transmission link,when transmitting WLAN wireless signals,the best EVM is 2.33%,and the dynamic range is 10 dB.When transmitting LTE-TDD wireless signals,the best EVM is 2.18%.The dynamic range is 22 dB.When transmitting WLAN/LTE-TDD signals in fiber-wireless hybrid transmission system with different wireless transmission distances,the best EVM ?1.95%,and the dynamic range can achieve 17 dB and 31 dB respectively.This system architecture effectively increases the capacity of the fronthaul network,reduces the cost,and improves the utilization rate of fiber resources.It is a support for capacity expansion of next generation B5G/6G system.In order to further expand the capacity of MCF-based RoF system,this paper construct a fiber-wireless hybrid RoF transmission system based on wavelength division multiplexing(WDM)and SDM technology.By transmitting multi-band and multi-standard wireless signals,the communication quality of the system is analyzed from both EVM and dynamic range.The experimental results show that in the multi-core fiber-only transmission link,when transmitting WLAN wireless signals,the best EVM?1.80%,and the dynamic range can achieve 18 dB.When transmitting LTE-TDD wireless signals,the best EVM ?2.40%,and the dynamic range is 25 dB.When transmitting WLAN/LTE-TDD signals in fiber-wireless hybrid transmission system with different wireless transmission distances,the best EVM ?2.09%,and the dynamic range can achieve 27 dB and 36 dB respectively.This network architecture can make full use of space and wavelength multidimensional resources,reduce costs,improve system capacity and fiber utilization.