Rand McNally licensed its BTA mapping data to the FCC for use in defining broadcast coverage areas for various services, including BRS licenses. BTAs are similar in size to the Metropolitan Statistical Area (MSA), a county boundary construct originally developed for census data, which was adopted by the FCC to define the licensed coverage areas for cellular telephone services.

The “Basic Trading Area” is an economic construct that corresponds to regional market interactions and economic interdependencies within an area defined by geopolitical criteria, namely county boundaries. A BTA can be thought of as the market being served by a wireless network.

By licensing in multiple county areas, the FCC was able to efficiently auction the BRS spectrum for the entire United States, and encourage wireless operators to expand broadband services into the less populated areas that are likely to be unserved or underserved. The value of the areas with lower population densities is higher when associated with a major market. The BTA is a more rational coverage area for a low power service, such as BRS, since a cellular network can be configured to serve irregularly shaped areas (defined by county boundaries) by using non-line-of-sight transmissions.

Transmissions from cell towers can be divided into sectors and channels can be reused in non-adjacent cells. These strategies make it possible to serve a larger area with less spectrum. A WiMAX network can serve a community with only two channel groups (8 channels).

In 1996, the FCC conducted an auction for all of the available commercial channels and vacant coverage areas within each BTA. The Protected Service Areas for any previously granted licensees were, of course, excluded from the auction.

Unlike the GSA for EBS spectrum, BTAs eliminate the problem of partitioning the coverage area of overlapping adjacent systems. The winner of the BTA auction takes all of the available BRS spectrum in the entire coverage area, and has a right of first refusal to lease the excess capacity airtime from licensees with Educational Broadband Service channels.

All spectrum within the 2.5 GHz band, including BRS, was initially licensed by the FCC as Geographic Service Areas with a 35-mile radius. BRS channels licensed before 1996 retained their original GSA/PSA boundaries, and continue to remain in force after the BTA auction was concluded. These pre-existing licenses are referred to as “incumbent” licenses.

In the future, the available EBS channels and vacant coverage areas (“white space”) may be auctioned by the FCC, and assigned a licensed coverage area for the BTA. Congress directed the FCC to auction any available spectrum, which was a departure from the exemption from fees for educational institutions and nonprofit organizations. The proceeds of the auctions are used to reduce the federal budget deficits. The FCC will likely allow commercial operators to partner with commercial wireless operators, who will pay the costs for the spectrum.

An alphabetical listing of the BTAs can be found on Wikipedia.org. Follow the link to a webpage for the major city in each area, which includes historical references and background information. The maps on the Wikipedia web pages are only of the major city itself (municipal boundaries) and not the BTA country boundaries. The background information may be useful in developing plans to serve the metropolitan area.

Below you will find BTA tools and materials (including Census data) that have been extracted from the FCC website.