"The creation of this map marked the beginning of a process to measure utilization of the Instructional Television Fixed Service frequency band at 2.5 - 2.69 GHz. Selectively polling publicly-available data from the FCC's Universal License System database, each point on the map represents a 12-mile radius of coverage around one or more transmission antennas located at various geographic locations (6,607 as of 07/23/2003). In April of 2003, the U.S. Federal Communications Commission released a Notice of Proposed Rulemaking (WT Docket No. 03-66) in response to a proposal by the Wireless Communication Association, National ITFS Association, and Catholic Television Network regarding the potential for restructuring the ITFS band.

Data Visualization: FCC ITFS Antenna Map (2003), Max Vilimpoc

Adoption of a Technology Neutral Band Plan

Beginning in 1996 and continuing to 2004, the Federal Communications Commission (FCC) amended its regulations several times to authorize digital, two-way, low power, and mobile uses. As a result of the rulemaking process, the 2.5 GHz spectrum was approved for transmitting high-capacity broadband data or Internet access services via low-power, cellular networks or high-power high site single antenna systems. The most important change in this process was the adoption of a new band plan that reassigned the interleaved ITFS channels to provide for contiguous spectrum.

In 2003, the FCC adopted a new band plan for the 2.5 GHz spectrum by reassigning each ITFS/MDS channel group to a new set of frequencies. An ITFS or MDS channel group was comprised of four 6 Megahertz (MHz) channels (for a total of 24 MHz). The 2.5 GHz was rearranged so that each new EBS or BRS channel group was composed of three contiguous 5.5 MHz channels and one 6 EBS/BRS channel in the high power mid-band, for a total of 22.5 MHz. Each licensee also received space in one of the two newly created guard bands.

Even though it provided a little less spectrum, each EBS and BRS channel group was far more valuable as it contained contiguous spectrum that could be divided by the wireless operator as need for the efficient operation of data networks. (The low power channels are not contiguous with the single high power channel.)

The EBS and BRS channel group assignments were positioned with 3 channels in a low power sub-band for cellular data networks, and one channel in a high power sub-band for high power transmissions available for television programming or data network backhaul.

One of the objectives of the FCC for the new EBS/BRS band plan was to reduce the likelihood of harmful electronic interference from adjacent systems. This was one of the rationales for rearranging the spectrum into contiguous channel blocks and grouping high and low-power users into separate parts of the band.

These regulatory actions removing usage restrictions had the combined effect of converting the ITFS band from a television specific configuration into the technology neutral design of EBS spectrum. Now EBS and BRS channels can be used for any type of service: analog or digital, one-way or two-way, high power or low power, or in a cellular network or from a single high site antenna. The FCC pursued this “technology neutral” approach, in order to let the market decide what services would be offered on the 2.5 GHz band.

BRS-EBS Band Plans. Source: Federal Communications Commission

These changes in the regulatory environment for 2.5 GHz spectrum took place gradually. The full impact of this evolution was not realized until 2004, when the FCC adopted flexible rules for the EBS and BRS services to facilitate the deployment of innovative wireless technologies and services, especially fixed and mobile wireless broadband services that use low power transmissions. 2.5 GHz spectrum is available to provide faster high-capacity wireless Internet access.

Wireless operators of low power data networks can now use the existing cell phone infrastructure for a rapid and less expensive deployment. The upload and download antennae for broadband data networks can be mounted on the cell towers originally built for (and that continue to serve) mobile phone services.

There are also important economic advantages for the community. The new Rules, taken together, promote competition between wireless and wireline broadband technologies. Competing “wireline” networks include Internet service from cable television services and the Digital Subscriber Line (DSL) provided over existing telephone lines.

The FCC policies are designed to encourage the deployment of three alternative “pipes” in each community. By promoting competition between technology and delivery systems, the agency is providing a means of allowing market forces to drive the prices for service to lower levels.

The technology neutral band plan was adopted by the FCC to support the introduction of “next-generation” wireless broadband services, some of which have yet to be designed. WiMAX is a fourth generation technology that combines voice and data on a single Internet protocol network.

The nonrestrictive usage rules for the new EBS/BRS band plan make it immune to technological obsolescence, available for rapid and less expensive deployment with minimal infrastructure, and capable of accelerating the adoption of new innovative services.

The FCC adopted procedures for the EBS and BRS licensees to “transition” their services and channels to the new band plan. This process is nearly completed.

A student enjoying the benefits of a connected notebook computer
using a Mobile WiMAX PC Card. Courtesy: Clearwire Corporation (Image Gallery).

Mobile WiMAX Networks

These regulatory changes have coincided with the development of a 4th Generation standard for mobile wireless broadband, called WiMAX, which is Intel’s successor to WiFi. According to the WiMAX Forum, the 2.5 Gigahertz band, where the EBS and BRS channels lie, is the available spectrum that is best suited for broadband wireless access services.

“Signal propagation in [the 2.5 GHz] band enables the deployment of mobile services in a cost-effective way. Higher frequencies (3.4-3.6 GHz or 5.7-5.8 GHz) are at present well suited for fixed and nomadic services.... The propagation properties in higher bands are less favorable to mobile access, with the exception of areas with high demand, as they reduce base station range and thus increase the deployment costs. In the 3.4 - 3.6 GHz band, nomadicity and limited mobility can be supported in areas where demand is high (e.g. in urban areas) and a high density of base stations is required to meet the capacity requirements.”

White Paper: Empowering Mobile Broadband, WiMAX Forum, 2007, page 12.

4G services integrate data and voice by using a single Internet Protocol network. This is a revolutionary, not merely evolutionary, change. Mobile WiMAX networks provide users with integrated access to voice, high-speed data, video-on-demand, and interactive delivery services from a variety of wireless devices.

Up until now, each wireless device required its own contract for services. Now, multiple devices, including GPS, Personal Digital Assistants, MP3 players, even cameras, and, of course, “netbook,” notebook, and laptop computers, can all be part of the same network. Add to that the mobility gained by wireless connectivity, and it becomes obvious that this new platform is indeed “revolutionary.”

Below you will find additional information from the FCC and the National Technology and Information Administration (part of the Department of Commerce) about the 2.5 GHz band and the government’s process for allocating broadcast frequency for a wide variety of uses.