Research Progress in Analog Links in Few Mode Fiber

Optical fibercan be seen as an idealmedium for analog signal links due to the following characteristics: very high bandwidth, low loss,light weight, small cross section, low cost, and high flexibility. Analog link over fiber has been applied in distributedantenna system, picocellularnetwork, and remote areas. Moreover, few mode fiber (FMF) is able to support higher-order and orbitalangular momentum (OAM) modes and further improve transmission capacity, having attracted increasing interest. Hence, a laudable goal would be tostudy the analog signal transmission performance in an FMF using high-order LP modes and OAM modes.

Jian Wang’s groupat Wuhan National Laboratory for Optoelectronics (WNLO), Multi-Dimensional Photonics Laboratory (MDPL), has been devoted to the research of analog links over FMF. Directed by Prof.JianWang, PhD candidate Jing Du experimentally investigates analog links using LP₀₁, LP_11a, LP_11b, OAM₊₁, and OAM_-1modes in a 5-km FMF, utilizing spurious free dynamic range (SFDR) of the second-orderharmonic distortion (SHD) to evaluate the analog link performance. The obtained results indicate that the analog link performance through FMF is mainly affected by mode relative loss. Mode features, such as average differential mode delays, have less influence on the link performance. The work has been published on Optics Express (Vol. 25, PP. 3613-3620, 2017) with title “Demonstration of analog links using spatial modes in km-scale few mode fiber”.

Figure 1 Experiment results of analog links using LP and OAM modes in FMF.

These works arepartiallysupported by the National Basic Research Program of China (973Program) (2014CB340004),the NationalNatural Science Foundation of China (NSFC) (11274131,11574001,61222502),the Program for New Century ExcellentTalents in University (NCET-11-0182),and theWuhan Science andTechnology Plan Project (2014070404010201).

Links of the published papers:

Jing Du, Dequan Xie, Chen Yang, and Jian Wang, "Demonstration of analog links using spatial modes in km-scale few mode fiber," Opt. Express 25, 3613-3620 (2017).

https://www.osapublishing.org/oe/abstract.cfm?uri=oe-25-4-3613&origin=search