Wireless local loop

Wireless local loop (WLL), is the use of a wireless communications link as the "last mile / first mile" connection for delivering plain old telephone service (POTS) or Internet access (marketed under the term "broadband") to telecommunications customers. Various types of WLL systems and technologies exist. Other terms for this type of access include broadband wireless access (BWA), radio in the loop (RITL), fixed-radio access (FRA), fixed wireless access (FWA) and metro wireless (MW). Fixed wireless terminal (FWT) units differ from conventional mobile terminal units operating within cellular networks - such as GSM - in that a fixed wireless terminal or desk phone will be limited to an almost permanent location with almost no roaming abilities. WLL and FWT are generic terms for radio-based telecommunications technologies and the respective devices, which can be implemented using a number of different wireless and radio technologies. Wireless local-loop services are segmented into a number of broad market and deployment groups. Services are split between licensed - commonly used by carriers and telcos - and unlicensed services more commonly deployed by home users and wireless ISPs (WISPs). Licensed point-to-point microwave was first deployed by AT&T Long Lines in the 1960s for high-bandwidth, interstate transmission of voice, data and television. AT&T's network covered the entire U.S., carried across hundreds of microwave towers, largely transmitting at 3700–4200 MHz and 5000–6200 MHz. The network was slowly obsoleted, starting in the late 1980's, as fiber optics became the solution of choice for communications backhaul. Following the Breakup of the Bell System on January 8, 1982, licensed point-to-point microwave solutions could be sold to enterprise and government accounts for their own private use. Frequently, the argument was to bypass wired local loops in order to save money or backup weak copper cables. In 1987, Microwave Bypass modified a high-frequency licensed microwave radio (23GHz) and developed the first 802.