Almost a decade ago, the commercial sector started looking at the unlicensed frequency band as an area that could be used to bring high-speed data communications to schools, libraries, community groups, hospitals, residents and businesses using a fixed wireless architecture. Several companies, including Apple Computer Inc., Hewlett-Packard Co. and the Wireless Information Networks Forum (WIN-forum) collectively proposed that the Federal Communications Commission allocate 300 MHz of spectrum in the 5-GHz range, comprising the 5150- to 5300-MHz band and the 5725- to 5875-MHz band.
On Jan. 9, 1997, the FCC adopted a Report & Order supporting high-speed digital communications through the creation of new wide-area LANs and facilitating wireless access to the National Information Infrastructure (NII), a widespread, interconnected network of networks, carrying numerous services. The FCC permitted flexibility in the design and operations, fostering the development of new devices and services.
Later, the FCC issued a Memorandum Opinion and Order (MO&O) that permitted fixed point-to-point Unlicensed National Information Infrastructure (U-NII) devices in the 5.725- to 5.825-GHz band to operate with 1 watt maximum transmitter output power and directional antennas of up to 23-dBi gain. In addition, it specified transmit power limits, clarified unwanted emissions limits and clarified regulations governing U-NII devices. The amendment added to the flexible capability of the U-NII operations without causing an increase in interference to incumbent operators sharing the same spectrum. This MO&O became effective Aug. 31, 1998.
U-NII is a broadband fixed wireless architecture using highly directional, high-gain antennas mounted at a fixed location. As compared with mobile, fixed wireless supports higher throughput and uses denser modulation schemes that require high signal-to-noise ratio, enabling data rates to be 10 Mbits/second and higher.