To meet the demand of 5 g carrying light module of low cost, promote the health development of related industries and recommended light module, module manufacturers, end users, equipment manufacturers, research institutes, such as the industry parties to power on the premise of guarantee the quality of light module, from the index comprehensive optimization, the scale and resources reuse, core components through several aspects to improve:

   (1) Evaluate the actual requirements of application scenarios and transmission distances, and comprehensively optimize the light module index requirements. Firstly, the link budget of the fronthaul module is optimized, and the selection ratio of industrial-grade lasers can be improved by properly relaxing the index. Second, some application scenarios, especially the metropolitan area, can relax the OSNR index of the system on the coherent light module (such as 1~2dB) according to the actual demand, can support more commercial DSP chips, and reduce the chip development cost by simplifying the coherent DSP function and algorithm. Thirdly, the output power requirements of the silicon-based coherent optical modules should be relaxed appropriately. For example, if the output optical power is relaxed to -15dbm level, the yield of silicon optical chips will be significantly improved.

   (2) The module scheme should focus as much as possible and make full use of mature technology schemes and industrial resources. First, the fronthaul light module is focused at 25Gb/s Duplex 300m, 25Gb/s BIDI 10/15km, etc. Second, the data center and transmission network are used in the medium and back light transmission module. Third, the 25Gb/s BIDI scheme adopts the mature BOSA packaging technology of 10Gb/s BIDI at the initial stage.