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CASTEL Wireless Broadband Network, Guangdong, China

Key Data

A number of international companies are taking advantage of the opportunities available in one of the biggest markets for fixed wireless broadband - China. The Adaptive Broadband Corporation has signed a contract with Casil Telecommunications Holdings Limited (CASTEL), which is based in China, that will make CASTEL a manufacturing and market access partner for fixed broadband wireless equipment in China. If all of the phases of the agreement are achieved, the contract has a potential value of more than $500 million during its 42-month term.

CASTEL is the telecommunications subsidiary of the China Aerospace Industry Corporation. CASTEL announced that carriers will initially deploy AB-Access (Adaptive Broadband's wireless broadband technology) in China's Guangdong province. The Guangdong province is the most affluent and technologically advanced province in China and it is leading the pace of internet access. That access is increasing at a tremendous rate, the Strategis Group suggests that the global wireless market could generate $10 billion by 2003.

CASTEL has already received commitments for field trials with Guangdong Telecom and several other provincial subsidiaries of China Telecom. Guangdong Telecom is the largest telecommunications operator in China. This represents the first use of AB-Access outside the USA and the first deployment of any kind of fixed broadband wireless technology in China. CASTEL's equipment manufacturing subsidiary, China Southern Telecom (CST), will assemble, manufacture and test the product. Adaptive Broadband will transfer the product's manufacturing technology to CASTEL, with the exception of its chip set, which will be supplied as a manufactured component.

Adaptive Broadband will retain all of the other intellectual property rights for AB-Access. CASTEL will market the equipment to carriers in China, under a private labeling agreement with Adaptive Broadband.


AB-Access is a point-to-multipoint broadband wireless technology that spans frequency ranges from 2 to 42GHz, providing data rates at speeds of up to 25mbps (megabits per second), over 400 times faster than is possible with a 56kbps modem and dial-up connection. Deployment in China is planned to occur in the 5.8GHz frequency, pending certification by the country's Ministry of Information Industry (MII). This frequency is designated in the USA as the Unlicensed National Information Infrastructure (U-NII) band. Since introducing AB-Access, Adaptive Broadband has developed additional versions for deployment in other frequencies, helping to extend the technology's global reach. A version for the multi-channel multipoint distribution service (MMDS) band between 2.5 and 2.7GHz was successfully tested in late 1999 and a third version, for the 3.5GHz frequency in Europe, was introduced in 2000.


AB-Access enables service providers to build point-to-multipoint cellular data networks in business and residential areas, with the ability to package and tariff the service in a variety of ways. An AB-Access network consists of subscriber units at the customer premises which provide either ATM or standard IP over Ethernet. Cell sites enable communication between the subscriber units and the wide area network via a number of sectors, each containing a transceiver (or access point) and a network manager to centrally manage the network via a graphical user interface.


The AB-Access subscriber unit provides the service subscriber, whether business or residential, with a standard IP over Ethernet or ATM connection for a single PC, or a network of PCs via a hub. The subscriber unit consists of a rooftop transceiver to communicate with the cell site, an internal wall junction box with a RJ45 socket to provide an Ethernet connection connected to the transceiver via an external data cable, a PC-based installation and a configuration application.


Each AB-Access cell site enables communication between a number of subscriber units and the wide area network. A cell site consists of an access point transceiver per sector, an ATM switch to interconnect the access points, the control server and the wide area network, and a control server to manage the cell site. The cell site has been designed as an integrated unit for ease of installation.


A single element manager, located on a workstation at an appropriate point in the network, is responsible for managing the elements of the AB-Access network. The key functions of the element manager are: maintaining and providing access to a database of subscriber and configuration information; managing system performance, statistics and maintenance via an element management application; and providing network statistics and configuration capabilities via a graphical user interface management client.