WLL systems are designed to provide operators with cost-effective fixed wireless solutions as an alternative to traditional wireline system deployment. Fixed wireless system implementation can provide rapid revenue generation to existing cellular operators in areas with established subscriber bases, to entrepreneurial operators licensed to provide basic telephone service in new areas, and to existing phone companies for areas not yet served.
Some of the scenarios where WLL systems can provide a competitive advantage in the market are:
§ Existing landline operators that need to extend their networks to remote locations
§ New service providers that need to deploy nontraditional wireless solutions to rapidly meet a community's telephone needs
As demand for basic telephone service increases in many areas of the world, alternatives to costly copper wire implementation become increasingly important to operators that are trying to meet subscriber demand. WLL systems can serve not only to supplement overloaded wireline networks in urban areas, but also to provide service to low-density rural areas.
The WLL systems are installed all over the world, but mostly in the developing countries of Asia, Africa, Latin America, and Western Europe, where a wireline infrastructure is either nonexistent or not extensive enough to keep up with the demand for communication services.
In China, for example, the Ministry of Post and Telecommunications specified WLL systems as an essential element of its five-year plan to install up to 14 million lines annually through the year 2000. The move reflects the government's efforts to establish access network standards for the entire country, as well as recognition among the highest levels of government that WLL systems are the only way to offer telecommunications services in a timely manner on such a massive scale.
In the city of Shanghai, with a population of over 12 million, 1300 new requests for telephone service are submitted to the local telecommunications authority every day. In addition, as the city undergoes extensive reconstruction projects, many potential and existing telephone users are being forced to move, which creates a substantial challenge for the telecommunications authority in planning and installing new lines.
CDMA-based WLL systems from Motorola, operating at 1.9 GHz, are being installed in Shanghai (and elsewhere in China) out of the need to reduce the telephone waiting list and to cope with continual large-scale urban changes. These systems are compliant with the European Telecommunications Standards Institute's (ETSI) V5.2 open standard interface, enabling their interconnection with existing PSTN switching platforms.
The V5.2 open interface, approved by the ETSI in 1994 and later approved as an International Telecommunications Union (ITU) standard, is intended to allow operators to mix and match local exchange equipment and local access equipment, irrespective of competing suppliers. Enhancements incorporated into the V5.2 standard allow for wireless extensions into the local telephone loop.
In 1995, Motorola and Fujitsu were among the first vendors to develop and deliver complementary products utilizing the V5.2 digital open interface for fixed wireless phone systems in the international market. The interface is available on Fujitsu's FETEX-150, a full digital switching system with an installed base of almost 30 million lines worldwide. The switch is especially popular in China, where 15 million FETEX-150 lines have been installed as of mid-1997.
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