Commercial Progress and Future Trends of 800G Optical Transceivers

Posted on Mar 20, 2024 by

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In recent years, the emergence of new services such as VR, IoT, and cloud computing has raised the bar for network bandwidth, concurrency, and real-time performance. As bandwidth demands continue to soar, while 100G, 200G, and 400G optical modules will maintain a significant market share, 800G optical transceivers are also poised to gain traction.

Electrical Interface and Optical Interface Architecture of 800G Optical Transceiver

Research indicates that for electrical interfaces, optimal architecture of optical modules is achieved when the single-channel rate of the electrical interface matches that of the optical interface, offering advantages such as low power consumption and cost-effectiveness. A single-channel 100 Gbit/s electrical interface is ideal for 8x100 Gbit/s optical modules, while a single-channel 200 Gbit/s electrical interface is suitable for 4x200 Gbit/s optical modules. Regarding packaging, 800 Gbit/s optical modules may come in various forms, including dual-density quad-channel small form-factor pluggable (QSFP-DD800) and eight-channel small form-factor pluggable (OSFP). There are three main types of optical interface architectures for 800G optical modules:

8×100G PAM4

The 8×100G PAM4 transceiver operates at 53 Gbd and utilizes 8 pairs of digital-to-analog converters (DACs) and analog-to-digital converters (ADCs), 8 lasers, 8 pairs of optical transceivers, along with 1 pair of 8-channel coarse wavelength division multiplexer (CWDM) or LAN-WDM multiplexer and demultiplexer based on Ethernet channels.

8×100G PAM4

4×200G PAM4

The PAM4 transceiver operates at 106 Gbd and employs 4 pairs of DACs and ADCs, 4 pairs of optical transceivers (including 4 lasers), along with 1 pair of 4-channel CWDM or LAN-WDM multiplexer and demultiplexer.

800G Coherent Optical Module

Operating at 128 Gbd under 16QAM modulation, it utilizes 4 pairs of DACs and ADCs, 1 laser, and 1 pair of optical transceivers. It can employ fixed-wavelength lasers in coherent optical modules within data centers to reduce costs and power consumption. You can also check out the 800G ZR/ZR+ article for more information on 800G coherent modules.

Commercial Progress of 800G Optical Transceiver

Driven by the digital economy and the metaverse, major clients in cloud data centers continue to ramp up capital expenditure, bringing significant attention to the optical module market. Since 2021, major manufacturers have been sequentially completing the development of 800G optical modules and initiating commercialization processes. At OFC 2022, several domestic communication manufacturers showcased their latest products.

HenTong Lockley unveiled the 800G QSFP-DD800 2xFR4 optical module tailored for next-generation data center networks. Additionally, XinYiSheng demonstrated its next-gen 800G optical module, leveraging Thin Film Lithium Niobate (TFLN) modulation technology, promising lower power consumption.

Huawei has even completed research and development and released an 800G adjustable ultra-high-speed optical module in London as early as 2020. Cambridge Technology directly stated that its developed 800G optical module product passed prototype testing last year and won a bid to be listed as a supplier for a major client. It is anticipated to achieve large-scale production by the end of 2022, marking the beginning of widespread commercial use of 800G optical modules.

Outlook on the Development Trends of 800G Optical Transceiver

At present, 800G optical modules are still developing continuously. There are three main directions for future development trends:

Single-mode deployment: Multi-mode fiber has a short transmission distance, making the development of single-mode optical interface schemes an inevitable trend, which will benefit SiPh technology.
Single-wave 200G deployment: The current bandwidth resources at 55 GHz are somewhat insufficient, but the prospects for 200G PAM4 SiPh modulators and silicon-based lithium niobate films are promising.
Coherent deployment: As the transmission rate increases, coherent technology solutions will further expand applications to shorter distances such as 40, 20, and 10 km based on the 80 km transmission distance.

As 5G, edge computing, data center expansion, and computational demands continue to rise, the pursuit of 800G optical modules intensifies in the optical communication industry. With Chinese enterprises significantly investing in core technologies, the rapid deployment of 800G optical modules accelerates, heralding new development opportunities in the Chinese optical module market.