This technology could open a new frontier in wireless communication with data rates ten times higher than current technology allows. The group’s transmitter is claimed to cover the frequency range from 275 to 305GHz. This frequency range is currently unallocated and is due to be discussed at the World Radiocommunication Conference (WRC) 2019.
The THz band’s frequencies are higher than those used by the millimetre-wave wireless local area network (from 57 to 66GHz), and the available bandwidths are wider. Since the speed of a wireless link is proportional to the bandwidth in use, THz is said to be suited to ultrahigh-speed communications.
Today, most wireless communication technologies use frequencies of 5GHz or below, with high-order digital modulation schemes, such as the quadrature amplitude modulation (QAM), to enhance data rates within limited bandwidths available. The research group says that QAM is feasible at 300GHz with CMOS and that THz wireless technology could offer a boost in wireless communication speed.
Minoru Fujishima, professor at Hiroshima University, said: “Today, we usually talk about wireless data-rates in Mbit/s or Gbit/s. But I foresee we’ll soon be talking about Tbit/s. That’s what THz wireless technology offers. Such extreme speeds are currently confined in optical fibres. I want to bring fibre-optic speeds out into the air.”
Prof Fujishima added that the research group plans to further develop 300GHz ultrahigh-speed wireless circuits.