Global Standard Sought on TV White Spaces Databases

A new working group of the Internet Engineering Task Force (IETF) wants to develop a global standard to determine what TV white spaces spectrum is available to non-licensed users. A global standard would make it possible to use spectrum that has been freed in many countries, vendors said.

Work has already progressed in the U.S. under the National Broadband Plan, said Neustar engineer Jonathan Rosen. “In the U.S., nine companies are building the databases” that will provide information about available spectrum, he said. “We're going to have to go beyond what we have done in the U.S. so far,” Rosen said, saying the goal is to get a nation- and frequency band-independent mechanism.

The key issue is how to query white space databases in different countries in order to quickly receive answers on which spectrum a device can use in a special location at a given time. The so-called white spaces are frequencies that are not fully used at the moment by the primary licensed user. TV channels for example don’t use their frequencies in every area or at every time, said Nokia engineer Basavaraj Patil during the IETF meeting. “Many governments are looking at ways to make more spectrum available,” Patil said. The opened-up frequencies would be an add-on to Wi-Fi and could be used for a variety of services, he said.

In the EU, the British regulatory body Ofcom is highly active, Patil said. The Electronic Communications Committee within the European Conference of Postal and Telecommunications Administrations in January published requirements for the possible operation of cognitive radio systems in the white spaces. For Europe, it’s still unclear if there will be one database, as favored by industry, or national ones.

Rosen said databases will be nation-specific to some extent, to include the local regulatory requirements. Lars Eggert, principal scientist at Nokia Research Center in Helsinki, said databases also must be standardized to a certain level in order to allow standard query formats. Experts believe one fixed requirement for the developers is the protection of existing primary, licensed spectrum users from any interference by the new, unlicensed users. Rosen said the standard envisaged would protect a polygon for each protected entity -- transmitters or receivers of primary licensed users: “If the whites space device is inside the polygon you cannot use this spectrum."

Other FCC requirements include security mechanisms with a registration mechanism, said U.S. officials. The working group, which is expected to be fully chartered by the IETF peers soon, also addressed privacy. “Since the location of a user device is involved, privacy implications arise and the protocol will have to have robust security mechanisms,” the proposed charter reads.