The National Institute of Information and Communications Technology (NICT, President: Dr. Masao Sakauchi) has successfully deployed the mobile broadband communications systems at more than 40 Mbps throughput, and has successfully established a 3.7km link between two locations within the framework of the TV White Spaces Pilot organized by Ofcom, the communications regulator of the UK.
The trials of NICT systems have been deployed in central London, a big city which has many incumbents to be protected, for example TV broadcasters and active wireless microphone users. NICT has also successfully developed a white space database which passed the qualification tests to be included in the Ofcom's databases list. This database provides protection from interference to the incumbents by calculating and providing information about available channels and maximum transmission power in each channel to the white space systems. NICT's trials which deploys TV white space mobile broadband communications based on database information in a crowded city is the first of its kind. The experiences obtained during the trials are expected to contribute to the development of TV white spaces regulations in the UK as well as other countries in the world.
Using TV white spaces is being considered as one of the potential solutions to the high demands on multi-user support and high speed to broadband wireless communications systems. The Ofcom, an independent regulator and competition authority for the UK communications industries has started the TV White Spaces Pilot which provides an opportunity for the stakeholders to conduct tests with their systems and to provide feedbacks to the development of white space communications regulation. In order to join the pilot, the devices have to conform to a set of specifications determined by ETSI which make sure that they will not interfere to the incumbents in the TV bands, while the databases have to conform to a set of specifications determined by Ofcom which requires them to provide operational parameters to the devices. NICT joined the Ofcom's pilot as both device developer and database developer. Because of the intensive and dynamic use of the spectrum in a large city, it is a challenge that the database uses the most updated incumbents' information to calculate the operational parameters for the devices in real-time, and the devices regularly communicates with the database to exchange operational parameters.
The antenna deployed at the roof of a building in Denmark Hill for the 3.7 km link establishment.
NICT has successfully established the 3.7 km wireless link between two locations, and has successfully achieved more than 40 Mbps throughput for broadband mobile systems in the TV bands. Both trials have been deployed in central London, a crowded city where the white space systems have to avoid interference to a large number of incumbents e.g. broadcasting users and PMSE (wireless microphone, in-ear monitor etc.) users. Using operational parameters provided by a database and successfully deploying mobile broadband communications system in a large city is the first trial of its kind. The details are as follows:
- NICT has developed IEEE 802.11af-based system and established wireless connection between two locations separated by 3.7 km in central London. NICT has developed an LTE-based system and provided high throughput at more than 40 Mbps between a base station and a mobile terminal in central London. Both of the systems developed by NICT conform with the ETSI specifications which defines a strict level of unnecessary power emissions in neighboring channels.
- NICT has implemented a TV white space database according to Ofcom's specifications. The database calculates and provides operational parameters to the white space systems by taking into account the dynamically changed information about spectrum usage of the incumbents such as TV broadcastings and wireless microphones. The operational parameters include locations, occupied channels, transmission power and transmission.
Based on the experiences and the results obtained from the trials, NICT plans to improve the performance of the devices and the database. NICT also expects to contribute these experiences to the development of white space relevant regulations in other countries, as well as to transfer their white space technologies to the stakeholders.
The detailed information is on the web page http://www.nict.go.jp/en/press/2014/07/24-1.html
Ha Nguyen Tran and Kentaro Ishizu
Smart Wireless Laboratory
Wireless Network Research Institute
E-mail: [email protected]
Public Relations Department
E-mail: [email protected]