Optical Transceiver: The core driving force in the field of optical communications

In the modern information society, high-speed and stable data transmission has become an indispensable cornerstone for all walks of life. In this data torrent, the optical transceiver (optical module) has become an important component for building a modern high-speed information network with its unique photoelectric conversion capability. As the core device for realizing the photoelectric conversion and electro-optical conversion functions of optical signal transmission in optical fiber communication equipment, the optical module not only carries the transmission of information, but also is a powerful driving force for the continuous development of communication technology.

The basic function of the optical module is to convert electrical signals into optical signals for transmission, and restore optical signals to electrical signals at the receiving end. This conversion process seems simple, but it contains complex technical principles. The optical transmitter (TOSA) at the transmitting end modulates the electrical signal into an optical signal through a semiconductor laser (LD), and then transmits it over long distances through optical fiber. The optical receiver (ROSA) at the receiving end uses a photodetection diode (PD) to convert the received optical signal into an electrical signal, which is then output after being processed by a preamplifier. In this process, the optical module not only needs to have high photoelectric conversion efficiency, but also needs to ensure the stability and integrity of the signal to cope with the complex and changing communication environment.

The development history of optical modules is full of innovation and change. From the early fixed-line telephone to 2G and 3G wireless communications, the development of communication technology has always revolved around electrical signals. With the increase of transmission distance and the increase of signal frequency, the loss and deformation of electrical signal transmission have become increasingly prominent, limiting the further improvement of communication speed and quality. In order to overcome this bottleneck, optical modules came into being, converting electrical signals into optical signals for transmission, thereby realizing long-distance, high-speed, and low-loss information transmission.

The types and functions of optical modules are also constantly evolving. From the early SFP (Small Form-Factor Pluggable) small package pluggable modules to the later XFP, SFP+ and other high-speed, miniaturized modules, optical modules not only have continuously improved their speed, but also have more flexible and diverse packaging forms. These modules support hot-swap and plug-and-play, which greatly simplifies the maintenance and upgrade process of network equipment. With the continuous development of silicon photonics technology, silicon photonic modules have become an important development direction in the future optical communication field with their advantages of low energy consumption, low cost, large bandwidth and high transmission rate.

Optical modules are increasingly used in data centers, telecommunications networks, access terminals and other fields. Especially in the construction of 5G networks, optical modules, as the basic components of the physical layer, play a vital role. The radio access network (RAN) of 5G networks is re-divided into active antenna units (AAU), distribution units (DU) and centralized units (CU), which puts higher requirements on optical modules. In the base station on the wireless network side, the fronthaul optical module between AAU and DU will be upgraded from 10G to 25G, and the demand for mid-haul optical modules between DU and CU has been newly added. These changes not only promote the continuous upgrading of optical module technology, but also provide strong support for the commercialization of 5G networks.

In the future, optical modules will continue to develop in the direction of high speed, small size, low power consumption, long distance and hot pluggable. With the continuous increase in users' demand for bandwidth of optical communication networks, the optical module industry will accelerate the pace of technological innovation and promote products to develop in the direction of higher speed, higher integration and lower power consumption. At the same time, the emergence of new technologies such as optoelectronic co-packaging (CPO) will further shorten the signal transmission path, improve performance, and bring new possibilities to the field of optical communications.