| 摘要 |
<p>In a digital communication system for use in a local area network, messages are conveyed over a cable, which may be an electrical cable or an optical fibre cable, using code division multiple access spread spectrum techniques. In such a system the message is modulated on to a quasi- random bit stream whose characteristics form an address for the terminal to which the message is directed. Such a system is known in specialised radio systems, but is not normally considered suitable for line communication because of inefficient use of the bandwidth. However, in a short-range local area network this disadvantage largely disappears.</p> |
