The DECT (Digital Enhanced Cordless Telecommunications) standard is the accepted standard in Europe for wireless telephony inside buildings. It enables mobile telephony, with good voice quality and with a range of approximately 50 metres or more around the DECT base station. Outdoor distances of up to 300 metres are theoretically possible.
In Europe, DECT uses the frequency range of 1880-1900 MHz for radio transmission. This range is different from that used by other short-distance wireless technologies such as Wi-Fi and Bluetooth. As a result, these technologies do not interfere with each other and can be operated in parallel. For the transmission of the actual voice audio, the G.726 codec is used, which, depending on the voice connection, requires a bandwidth of 32 kbit/s. Most private households use the solution known as Single Cell DECT. A DECT base station connects to the telephone network and allows up to six DECT cordless handsets to connect to the base station. For larger businesses and buildings in which a greater number of cordless phones are to be supported, the Single Cell DECT solution is no longer sufficient. In this instance, Multi Cell DECT installations are used.
Multi Cell installations like this support numerous base stations and provide a comprehensive DECT radio network, with multiple cells. This makes it possible, depending on the number of supported cells and base stations, to operate hundreds of handsets throughout the premises. As the individual radio cells overlap within the building, connections are automatically transferred when changing from one cell to the other, meaning that calls are continued without interruption. This is known as the so-called “seamless handover”. For those making the calls, this makes it perfectly possible to move freely within the area served by the Multi Cell DECT during a phone call.