Hiroshima University, National Institute of Information and Communications Technology, and Panasonic Corporation announced the development of a terahertz (THz) transmitter capable of transmitting digital data at a rate exceeding 100 gigabits (= 0.1 terabit) per second over a single channel using the 300-GHz band. This technology enables data rates 10 times or more faster than that offered by the fifth-generation mobile networks (5G) expected to appear around 2020.
Details of the technology will be presented at the International Solid-State Circuits Conference (ISSCC) 2017 to be held from February 5 to February 9 in San Francisco, California.
The THz band is a vast new frequency resource expected to be used for future ultra-high-speed wireless communications. The research group has developed a transmitter that achieves a communication speed of 105 gigabits per second using the frequency range from 290 GHz to 315 GHz. This range of frequencies is currently unallocated, but fall within the frequency range from 275 GHz to 450 GHz, whose usage is to be discussed at the World Radiocommunication Conference (WRC) 2019. Last year, the group demonstrated that the speed of a wireless link in the 300-GHz band could be greatly enhanced by using quadrature amplitude modulation (QAM). This year, they showed a six times higher per-channel data rate exceeding 100 gigabits per second for the first time as an integrated-circuit-based transmitter. At this data rate, the contents of an entire DVD can be transferred in a fraction of a second.
“This year, we developed a transmitter with 10 times higher transmission power than the previous versions. This made possible a per-channel data rate above 100 Gbit/s at 300 GHz,” said Prof. Minoru Fujishima, Graduate School of Advanced Sciences of Matter, Hiroshima University. “We usually talk about wireless data rates in megabits per second or gigabits per second. But we are now approaching terabits per second using a single communication channel. Fiber optics realized ultra-high-speed wired links, and wireless links have been left far behind. Terahertz could offer ultra-high-speed links to satellites as well, which can only be wireless. That could, in turn, significantly boost in-flight network connection speeds, for example. Other possible applications include fast download from content servers to mobile devices and ultrafast wireless links between base stations,” said Prof. Fujishima.
NICT was established as an Independent Administrative Institution in 2004 when Japan’s Communications Research Laboratory (established 1896) merged with the Telecommunications Advancement Organization. Today NICT’s mission is to carry out research and development in the field of information and communications technology.
It has a range of responsibilities including generating and disseminating Japan’s national frequency and time standards; conducting type approval tests of radio equipment for the Global Maritime Distress Safety System (GMDSS) and marine radar based on Japan’s Radio Law; and providing regular observations of the ionosphere and space weather. It also operates the JJY, a low frequency time signal.
In late August 2015, it was announced that a terahertz radiation scanner developed by the institute would be one of the instruments carried by the ESA’s Jupiter Icy Moons Explorer, currently due for launch in 2022.
Realizing Compact, Low-Cost, High-Speed Radio Communication Systems for the IoT Age
In collaboration with the National Institute of Information and Communications Technology (NICT), Associate Professor Hiroyuki Ito and Professor Kazuya Masu, et al., of the Tokyo Institute of Technology, developed a new algorithm and circuit technology allowing high-frequency piezoelectric resonators to be used for phase locked loops (PLL). It was confirmed that these operate with low noise and have an excellent Figure of Merit (FoM) compared to conventional PLLs.
This technology allows high-frequency piezoelectric resonators to be used in place of crystal oscillators which was a problem for realizing compact and low-cost radio modules. This greatly contributes to the creation of compact, low-cost, high-speed radio communication systems for the IoT age. High-frequency piezoelectric resonators are compact, can be integrated, have an excellent Q value, and oscillators that use these have excellent jitter performance. High-frequency piezoelectric resonators had greater issues with resonance frequency variance and temperature dependability compared to crystal resonators. However, these issues were resolved by the development of a PLL that uses a channel adjustment technique, which is a new algorithm.
A prototype was fabricated by a silicon CMOS process with a minimum line width of 65 nm, and a maximum frequency output of approximately 9 GHz was achieved with a phase fluctuation of only 180 femtoseconds. Power consumption was 12.7 mW. This performance is equivalent to a PLL Figure of Merit (FoM) of -244 dB, and it has the world’s top-class performance as a fractional-N PLL. This can contribute to the realization of compact, low-cost, high-speed radio communication systems.
Hiroshima University, the National Institute of Information and Communications Technology, and Panasonic Corporation announced the development of a terahertz (THz) transmitter capable of signal transmission at a per-channel data rate of over ten gigabits per second over multiple channels at around 300 GHz. The aggregate multi-channel data rate exceeds one hundred gigabits per second. The transmitter was implemented as a silicon CMOS integrated circuit, which would have a great advantage for commercialization and consumer use.
This technology could open a new frontier in wireless communication with data rates ten times higher than current technology allows.
Details of the technology were presented at the “International Solid-State Circuit Conference (ISSCC) 2016,” held from January 31 to February 4 in San Francisco, California.
The THz band is a new and vast frequency resource not currently exploited for wireless communications. Its frequencies are even higher than those used by the millimeter-wave wireless local area network (from 57 GHz to 66 GHz), and the available bandwidths are much wider.
Since the speed of a wireless link is proportional to the bandwidth in use, THz is ideally suited to ultrahigh-speed communications.
Will form the foundation for the future Internet infrastructure
With optical fibre networks gradually approaching their theoretical capacity limits, new types of fibres such as multicore fibres have been at the focus of worldwide research to overcome critical capacity barriers, which threaten the evolution of the Internet. The University of Bristol in collaboration with the National Institute of Information and Communications Technology (NICT) have demonstrated successfully for the first time a multicore fibre-based network, which will form the foundation for the future Internet infrastructure.
The research relies on Space Division Multiplexed (SDM) provided by the multicore fibres and on Software Defined Network (SDN) control, which are considered promising solutions to fulfil and control the ever-increasing demand for data consumption in communication networks.
This collaborative work between the High Performance Networks Group at Bristol and NICT, Japan, represents the first successful demonstration of a fully functional multicore fibre network taking advantage of the flexibility and intelligence that SDN can offer in order to provide services to emerging Internet applications such as global cloud computing.
The Bristol research team developed the SDN control based on extensions of the OpenFlow protocol and provided the novel network node equipment while NICT contributed multicore fibres (MCFs) and new transmission techniques based on self-homodyne detection (SHD).