Cordless telecommunications in the UK

There is a growing demand for portable telephones in the UK. In addition to the excellent but expensive service provided by the cellular telephone networks, there is a large demand for low - cost products which can provide limited coverage around a house or factory premises. The devlopment of suitable systems to make best use of any available spectrum presents interesting technical and commercial challenges. The first generation of cordless telephones in the UK are similar to their US counterparts, using 8 channels in the 1.6 and 47 MHz bands, but must be approved to a specification which includes a requirement to provide security of acess to the telephone line. They must also give similar speech performance to that of a wired telephone. The specification, first published in 1982, has recently been extended to include a requirement for continuous security handshaking, and to allow attatchment to leaky feeder antennas. Advanced cordless telecommunications systems are now under study. These will use digital modulation, which will provide higher traffic capacity and allow the possibility of speech privacy. The specification for these second - generation CTs is now well advanced and it is expected that they will be commercially available in three years or so. Propagation in and around buildings has been extensively measured, at 900MHz and 60GHz, including an investigations of diversity and the use of leaky feeders. The 175 - 220 MHz band has been re-allotted for mobile systems in the UK, athough it will continue to be used for television broadcasting in neighbouring countries. Five bands each of 1 MHz bandwidth have been allocated for business cordless applications. The specifications for these are now under discussion.