At OFC 2025, Keysight Technologies, NTT Innovative Devices, and Lumentum demonstrated a groundbreaking 448 Gbps per-lane optical transmission using 224 GBaud PAM4 technology, setting the stage for future 3.2T optical interfaces optimized for AI and machine learning data centers. The joint effort leverages a combination of ultra-high-speed waveform generation, advanced frequency-domain signal processing, and cutting-edge indium phosphide (InP) laser technology, delivering the bandwidth and efficiency demanded by next-generation infrastructure.
The demonstration showcased the generation and analysis of 224 GBaud PAM4 signals using Keysight’s M8199B Arbitrary Waveform Generator and N1032A DCA-X Sampling Oscilloscope, along with NTT’s frequency-domain interleaver and Lumentum’s InP externally-modulated laser. This platform not only enables 448 Gbps per lane transmission but also demonstrated the successful generation of 240 GBaud PAM4 signals, pushing performance boundaries beyond current standards. The results highlight a pathway toward scalable, energy-efficient interconnects for AI workloads that require ultra-fast, real-time data processing.
This collaborative breakthrough addresses a key challenge for AI and ML applications: scaling bandwidth between compute and network nodes while minimizing power draw and latency. As models grow increasingly complex, high-speed, power-efficient optical links are essential to avoid bottlenecks and reduce operational costs across data center networks. The success of this demo brings the industry closer to commercializing 3.2T optical modules and 400G/lane technologies.
• Demo achieved 448 Gbps data rate per lane using 224 GBaud PAM4 modulation.
• Utilized Keysight M8199B AWG (256 GSa/s, >80 GHz analog bandwidth) and N1032A DCA-X (up to 120 GHz optical bandwidth).
• NTT’s frequency-domain interleaver extended signal generation bandwidth.
• Lumentum’s InP externally modulated laser enabled high-speed optical transmission.
• Demonstration also generated 240 GBaud PAM4, showcasing scalability.
• Designed to support future 3.2T interfaces for AI and ML applications.
• Showcased at OFC 2025, Booth #1301, from April 1–3.
“This collaboration showcases the cutting-edge advancements in high-speed optical communication and highlights the combined strengths of Keysight, NTT Innovative Devices, and Lumentum,” said Dr. Joachim Peerlings, Vice President of Network and Data Center Solutions at Keysight. “This demo is another milestone for Keysight to enable the industry in advancing the AI infrastructure.”
“We are confident that we have prepared the fundamental technologies necessary to realize 400G/lane in a timely manner,” said Dr. Akimasa Kaneko, Executive Vice President, Photonic Component Business Group at NTT Innovative Devices. “We hope that this will help further develop this industry.”
“Achieving 448 Gbps transmission is a significant milestone in advancing optical interconnects for AI-driven cloud infrastructure,” said Dr. Matthew Sysak, CTO of Cloud and Networking Platform at Lumentum. “Our externally modulated lasers will be instrumental in enabling faster, more efficient, and scalable data center networks.”
