World's-first compact transceiver for terahertz wireless communication using 300-GHz band

We develop compact transceiver with transmission rate of several-dozen gigabits per second and experimentally demonstrate high-speed data transmission, enabling a service for transferring one DVD's worth of data in a few seconds

http://www.eurekalert.org/pub_releases/2016-06/nioi-wct060916.php

NATIONAL INSTITUTE OF INFORMATION AND COMMUNICATIONS TECHNOLOGY (NICT)

Nippon Telegraph and Telephone Corporation (NTT; head office: Chiyoda-ku, Tokyo; president & CEO: Hiroo Unoura), Fujitsu Limited (Fujitsu; head office: Minato -ku, Tokyo; president & CEO: Tatsuya Tanaka), and the National Institute of Information and Communications Technology (NICT; head office: Koganei city, Tokyo; president: Masao Sakauchi) have cooperatively developed the world's-first compact terahertz wireless transceiver using the 300-GHz band and experimentally demonstrated that it can transmit data at transmission rate of 40 gigabits per second through multiplex transmission using orthogonal polarization. Since the transceiver can assure a broad frequency band, it is expected to be applied for high-speed wireless communication. Moreover, in the present development, under a supposed usage case in which large-capacity contents are downloaded from an information terminal (such as downloading video and music), the transmitter of the developed transceiver was installed in such an information terminal. Moreover, according to the results of a contents-downloading experiment using a compact (i.e., smartphone-sized) terminal fitted with a matching developed receiver, data transmission of two gigabytes per second (namely, downloading at a rate of one DVD's worth of data in about three seconds) was achieved. Through this experiment, it was shown that a compact transceiver using terahertz waves in the 300-GHz band--as well as the accompanying elemental circuit technology--could achieve large-capacity transmission. From now onwards, it is expected that technologies utilizing terahertz waves in the 300-GHz band will make major advances. The developed technology was presented in detail at IMS2016 (2016 IEEE MTT-S International Microwave Symposium) held in San Francisco from May 22nd, 2016. 

1 Background

As broadband networks continue to spread, investigations on high-speed data transmission via wireless communication are progressing across the world. To attain transmission rates at the level of the several-dozen gigabits per second (which will enable uncompressed realtime wireless transmission of ultra-high-definition images and instantaneous transfer of large-capacity data), it is necessary to utilize presently unused frequency bands. In particular, it is necessary to develop a compact wireless device that can handle high-speed data transfer. Terahertz wireless communication is a promising technology for meeting that need, and utilization of the 300-GHz band (which is presently unused by industry) is expected to open up new frequency resources. 

2 Results of experiment

(1) Experiment on high-speed data transmission using a compact transceiver for terahertz wireless communication

In this experiment, an InP-based high-electron-mobility transistor (InP-HEMT) was used as an ultrahigh-speed device and incorporated in a high-frequency transceiver circuit designed as an integrated circuit (IC). In this manner, a compact transceiver for terahertz wireless communication using the 300-GHz band was created. The transmitter enables 20-Gbps data transmission as an integrated architecture connecting (via a waveguide) a metal package housing the IC and an antenna . Moreover, under the assumption that the receiver will be mounted in a smartphone-sized terminal, mounting the IC in the antenna-integrated metal package resulted in an overall size of 1 cc (previously reported). The receiver demodulates a 20-Gbps wireless signal (received via the wireless section) and outputs it as a data signal. In addition, as for radiowave propagation and measurement technology concerning the 300-GHz band, high-speed data transfer was verified by an experiment performed in an anechoic chamber.

In this verification experiment, the transmitter and a signal processor for forward error correction (FEC) etc. (both developed by NTT), the receiver (developed by Fujitsu), and the radiowave propagation and measurement technology (developed by NICT) were brought together in the configuration. With the developed transmitter and receiver set facing each other, 20-Gbps data transfer was achieved. As a result, as for transmission distances exceeding 1 m, the possibility of error-free transmission was confirmed. 

Furthermore, an experiment on polarization-multiplexing transmission using two transceiver sets and a polarized waves perpendicular to each other was performed, and the results of the experiment confirmed that 40-Gbps data transfer is possible. These experiments confirmed sufficient performance as a wireless device transceiver and the utility of the developed technology. 

(2) Verification experiment simulating a data-downloading service

With the developed transmitter installed in an information terminal, and the matching developed receiver installed in a smartphone-sized terminal, a verification experiment simulating a service for downloading data (by touching the smartphone-sized terminal on the information terminal) was performed. In this experiment, video files stored in a PC on the transmission side (i.e., a contents server) were used, and the transfer rate concerning those files was evaluated. As a result, high-speed downloading of data at 2 GB/s (gigabytes per second)--equivalent to downloading at a rate of one DVD's worth of data in about three seconds--was confirmed. Under the aim of providing a high-speed downloading service, although investigations on using millimeter waves are presently progressing, the effectiveness of using terahertz wireless communication to further increase data-transfer rate was confirmed in this experiment.

3 Future developments

From now onwards, while further increasing data-transfer rate and improving efficiency of the communication sequence, in anticipation of studies on frequency utilization, we will continue our vigorous investigations on usage cases in addition to contents downloading

Focus on RIken and NICT Terahertz Database

My Note: Thanks to Piero TeHdeschi,  for posting a link to this THz, database.
http://thzdb.org/
The website provides:
In 2007, two publicly viewable online databases have been developed in Japan; RIKEN THz Database and Terahertz Spectral Database from NICT. The former contains around 200 spectra of pure reagent-grade materials, obtained with specified procedures. Text data are also provided with precise information about the measurement conditions. The later contains also around 200 spectra of materials used in art and art conservation, designed to demonstrate the applicability of terahertz spectroscopy in a certain field. We believe that the establishment of the spectral database is essential for THz spectroscopy or THz technology to be a common tool in industries and academics in various research fields, as we have commercial spectral library in mid-infrared spectroscopy.

The two organisations agreed to merge all data even though the applicable fields and quantitativeness are different. The aim of this project is to collect spectra which are useful in any fields, obtained by any system at any conditions by inviting contribution from organisations. This 'platform' should trigger the activity of accumulating spectral database, and encourage the practical use in various research fields around the globe.

This new keyword searchable database contains approximately 500 spectra, including contributions from Laboratory of Terahertz Bio-engineering of Tohoku University.

Keyword can be a part of material common name (casein, etc.), system (TDS, FTIR), mode (Transmission, Reflection), or organisation which carried out the measurement (NICT, RIKEN etc. )

We request that when you use the data of our Terahertz Database in your publication or presentation, a proper acknowledgement or reference is given as follows: Terahertz Database : http://www.thzdb.org

We are preparing a guideline for participation, including the data format of submission, and will organise a committee for database maintenance. Contributors retain the copyright on their own submitted data. If you are planning to participate to this database project, please do not hesitate to contact us.

NEC Successfully Demonstrates Terahertz Camera For Uses Including Fire Fighting And Rescue

MY NOTE: THE LIST OF APPLICATIONS AND USES FOR THz, GROWS, AND GROWS

http://www.efytimes.com/e1/fullnews.asp?edid=59901&magid=30
NEC Corporation, in cooperation with The University of Tokyo and the National Institute of Information and Communications Technology (NICT), announced today the successful demonstration of terahertz wave (*1) image measurement technologies that deliver superior results at fire scenes to conventional image measurement technologies that use visible light or infrared. 

The demonstration was carried out using NEC and NICT jointly developed high sensitivity real-time uncooled terahertz camera,featuring terahertz wave image measurement technologies that enabled successful imaging through clouds of black smoke at a simulated fire scene. 

These results were realized through Commissioned Research and Development for Advanced Communication and Broadcasting Research and Development, sponsored by the NICT. 

Terahertz waves are electromagnetic waves situated between infrared waves and radio waves. Terahertz waves are helping to drive the advancement of technological research for measurement and communications as they can be transmitted through paper, plastic and smoke. Specifically, terahertz image measurement is attracting attention as a next-generation non-destructive testing technology that is considered to be safer than X-rays. 

There is a constant demand for image technologies that enable rescue workers to penetrate the black smoke that engulfs fire scenes and allows them to visually understand their surroundings. Terahertz wave technologies are believed to meet this need, but their effectiveness in a fire scene has been difficult for conventional technologies to verify due to the terahertz wave tendency to be easily absorbed by the atmosphere. 

In April 2008, NEC developed a high sensitivity bolometer (*2) type uncooled two-dimensional terahertz array sensor (*3). Since then, the company has developed a high sensitivity real-time uncooled terahertz camera and continued activities for improving the sensitivity of the array sensor. 

Looking forward, NEC will continue to promote the development and commercialization of terahertz image measurement devices and to contribute to the fields of nondestructive inspection, medical treatment, drug development and illicit object detection.



NEC will exhibit the new terahertz camera at SECURITY SHOW 2011 at Tokyo Big Sight from March 8-11.