With the advent of the 5G era, the demand for wireless optical modules will increase significantly in the next few years, and the growth points will be mainly concentrated on 25G, 50G and 100G optical modules. According to research institute Light-Counting data, 10G optical modules are mainstream applications in the 3G and 4G eras, and in the 5G era, 25GGrey, 2*25GDSFP and 100Ggrey have become mainstream.


Figure Wireless optical device demand trend forecast

In the 5G era, the entire network architecture will change, what opportunities will the optical module encounter? What new requirements are proposed for the bearer network optical module in the 5G era? In a 5G communication technology forum, Jiang Bo, manager of the marketing department of Guangxun Technology, and Xie Yaohui, senior network architecture planner of Huawei, elaborated on the above issues.

Optical module market demand increases
Optical modules, also known as optical transceivers, are usually composed of light-emitting components (including lasers), light-receiving components (including photodetectors), drive circuits, and optical and electrical interfaces. Its role is to achieve the conversion of electro-optic and photoelectric signals.

At the transmitting end, a certain rate of electrical signals is processed by the driving chip to drive a laser (LD) to emit a modulated optical signal of a corresponding rate, and an optical power stable control circuit outputs an optical signal with stable power. At the receiving end, a certain rate of optical signal input module is converted into an electrical signal by a photodetector (PD), and an electrical signal of a corresponding rate is outputted through the preamplifier.

If the entire network is viewed as a highway of information, then the highway is ultimately implemented by optical modules. Huawei's senior network architecture planner Xie Yaohui said that the commercial value of optical modules is reflected in the large-bandwidth high-speed interconnection, covering tens of meters to thousands of kilometers.


Figure Optical module is the basic component of network high-speed interconnection

In the 5G era, the entire network architecture will also change. Compared with the 3G and 4G eras, the 5G network architecture has more than one pass, and the emergence of the middle pass will increase the use of optical modules. This is the 5G era for optical modules. Market opportunities brought. At the same time, changes in the network architecture have also placed new demands on optical modules.


Figure 5G Architecture evolution of the radio bearer network

4 new requirements for optical modules
According to the White Paper on 5G Optical Modules Released by the IMT-2020 (5G) Promotion Group, the 5G bearer network is generally divided into the metro access layer, the metro aggregation layer, the metro core layer/province trunk line, and realize the pre-transmission of 5G services. And the medium backhaul function, in which the devices at each layer mainly rely on optical modules for interconnection.

Therefore, in the 5G bearer network, the optical module is the basic building block of the network physical layer, and is widely used in wireless and transmission equipment. The cost of the optical module is increasing in the system equipment, and even more than 50-70% in some devices. The key elements of 5G low cost and wide coverage.

In the 5G era, the requirements for optical modules are also different from before. Jiang Bo, manager of the marketing department of Guangxun Technology, summarized four points, which are more heat-resistant, more optical, cheaper and faster.


Figure Requirements for carrying a network optical module

First, the entire network architecture evolves from CPRI to eCPRI. More is the BBU to do some migration to the RRU. This inevitably brings more power to the RRU. Therefore, the optical module is more resistant to heat. .

Second, there is a migration of the front-end architecture, and DRAN becomes CRAN, which brings a shortage of optical cable resources. Therefore, optical modules need to be able to provide some solutions that can save fiber.

Third, the entire 5G frequency band is higher than before, and its coverage becomes smaller. Therefore, more base stations are needed, and more optical modules are needed. From the perspective of the operator, the optical module needs to be cheaper.

Fourth, the entire 5G regardless of the operating low-frequency band or millimeter wave, if you use millimeter wave, the start is hundreds of megabytes, the bandwidth of the whole process will be higher and higher, so you need a higher speed optical module.