Keysight Helps to Achieve 1Tbps Throughput Using Terahertz Frequencies

Paper presented at Asia-Pacific Microwave Conference with CNRS, Lille University, and Osaka University details accomplishment.  

The demand for more cellular data and higher data throughputs is insatiable. The goal for 6G is to achieve data throughput rates 10-times faster than in 5G, eventually achieving up to 1 terabit per second (Tbps) throughput. This speed will enable use cases such as holographic communications and extended reality experiences that aren't possible with today's data speeds. 

To reach 1 Tbps speeds, several tens or hundreds gigahertz of bandwidth are needed, which makes higher frequencies like sub-terahertz (sub-THz) appealing. Currently there is extensive research into creating early sub-THz communications systems, but components for these frequencies are still under development and very scarce.

In December, Keysight and researchers from France's Centre national de la recherche scientifique (CNRS), Lille University, and Osaka University announced they had broken the 1Tbps barrier. In a paper presented at the Asia-Pacific Microwave Conference, professors Guillaume Ducournau and Tadao Nagatsuma detailed this achievement using a system built with a combination of terahertz photodiodes and an electronics-based receiver covering a range of 500-724 GHz. In this frequency band, they used channel aggregation with 14 carriers and a range of 16 to 64 quadrature amplitude modulation (QAM) to achieve a total data throughput of 1.04 Tbps.  

To measure the performance of their state-of-the-art system, they used a four channel Keysight Infiniium UXR‑series oscilloscope coupled with vector signal analysis (VSA) software. Figure 1 shows the measured performance of the carrier aggregated system in yellow between 500-724 GHz, with 14 total carriers. The measured performance of a single carrier at 632 GHz is shown below in Figure 2. The high performance of the UXR made these measurements possible. The four 70 GHz channels and wide supported voltage range made it possible to receive the full bandwidth of their signals. In addition, the large library of supported waveforms in the VSA allowed the researchers to demodulate their signals with ease to successfully measure the system throughput.  

"The combination of wideband terahertz photodiode, receiver and the unique performance of Keysight's UXR really enabled to succeed in these experiments," said Prof. Ducournau. "Their advanced instruments are really pushing forward our terahertz research." 

Figure 2: Measured throughput of signal carrier signal at 632 GHz with different modulations. 32-QAM / 40 GBaud (0.2 Tbps, left) and 16-QAM / 40 GBaud (160 Gbps, right). 

Photonics is one new technology that is being investigated to enable communications at sub-THz bands. Whether or not photonics will be widely adopted in the future remains to be seen, but Keysight remains committed to providing the tools that researchers need to build the next generation of wireless communications devices.