Keysight Technologies, NTT NInnovative Devices and Lumentum Holdings (“Lumentum”) demonstrated 448 Gbps data transmission using 224 GBaud PAM4 optical technology. the demo took place at the Optical Fiber Communication Conference and Exhibition (OFC) 2025.
This collaboration addresses the escalating bandwidth demands of artificial intelligence (AI) and machine learning (ML) applications, enabling the development of power-efficient 3.2 terabit (Tbps) interfaces for future data centre networks.
Keysight is enabling the industry in the early R&D stage for 448 Gbps. During this early R&D innovation phase, experts explore various modulation schemes, including PAM4, PAM6, and PAM8.
Notably, for 224 Gbps optical transmission, the industry has already embraced PAM4 as the preferred choice, highlighting the industry's commitment to pushing the boundaries of high-speed data transmission and setting new standards for the future.
AI and ML applications require ultra-fast, real-time data processing. The 448 Gbps transmission speed accelerates data movement between compute and network nodes, reducing latency and enhancing AI/ML model efficiency. As these models become increasingly complex, higher data throughput is essential to support scalability without bottlenecks.
Additionally, this breakthrough improves data centre efficiency, lowering operational costs and minimizing environmental impact.
The demonstration utilizes two Keysight M8199B Arbitrary Waveform Generators with NTT’s advanced frequency-domain interleaver to generate 448 Gbps electrical signals with 224 Gbaud PAM4.
This signal is used to drive a Lumentum indium phosphide (InP) externally-modulated laser (EML), showcasing the potential for high-speed, power-efficient optical interconnects. Successful generation of 240 Gbaud PAM4 is also demonstrated using the same hardware.
The demonstration features the latest 224 GBaud and beyond PAM4 technology, which enables 448 Gbps per lane data transmission and paves the way for developing power-efficient 3.2T interfaces for data centre networks (DCN). This achievement represents a significant leap forward in achieving higher data rates and improved signal integrity.
The joint demonstration consists of:
- Keysight’s M8199B arbitrary waveform generator operating at 256 GSa/s with analogue bandwidth exceeding 80 GHz.
- Keysight’s N1032A DCA-X sampling oscilloscope, ideal for analysing high baud rate optical signals with up to 120 GHz optical bandwidth.
- NTT’s frequency-domain interleaver, available as Keysight M8159A, which extends the bandwidth of the M8199B AWG.
- Lumentum’s high-bandwidth InP externally-modulated laser (EML).
The Keysight M8199B Arbitrary Waveform Generator and Keysight N1032A/B DCA-X Sampling Oscilloscopes are part of the Keysight Artificial Intelligence (KAI) architecture, a portfolio of end-to-end solutions designed to help customers scale artificial intelligence (AI) processing capacity in data centres.
