Testing The Instruments Of Tomorrow

Sept mber 19E8 TESTING THE INSTRUMENTS OF TOMORROW The increasing use of digital technology, rather than the previous generation of ana- logue systems, in both satellite and terrestrial communications, has resulted in a demand for widely differing testing tech- niques. Even though the inte- grated services digital network (ISDN) may largely still be in the future, planning for the necess- ary testing must be carried out in parallel with the planning of the networks themselves. These needs have been exacer- bated by the introduction of fibre optics which allows a single fibre, with its diameter measured in micrometres rather than millimetres, to carry far more traffic than a bunch of coaxial cables, each 10 mm in diameter. In addition, there have been major technical advances in mobile communications. Here, one of the outcomes is cellular radio, which relies for its oper- ation on sophisticated tech- niques originally developed for radio equipment for military and defence purposes....