| 词条 | Quadrature-division multiple access |
| 释义 |
}} Quadrature-division multiple access (QDMA) is a radio protocol.[1] The term combines two standard terms in telecommunications, CDMA and QPSK. ApplicationsQDMA is used for local area networks, usually wireless short-range such as WiMax. CDMA and QDMA are especially suitable for modern communications, for example, the transmission of short messages such as SMS or MMS; communication when in motion (from cars, trains, etc.); the establishment of unplanned links. Benefits over TDMA and FDMA{{Unreferenced section|date=July 2010}}The traditional TDMA and FDMA require a lot of overhead to set a link parameter with a new user, or to detect that a user left and their allocation is free to be allocated to another. In CDMA or QDMA, a new user is simply allocated a new code and is ready to go. It may impose a slight load on the spectrum, but the system is so devised as to absorb a controlled measure of collisions and continue operations at a high level of quality of service. References1. ^{{cite book|last=Held|first=Gilbert|title=Wireless mesh networks|year=2005|publisher=CRC Press|isbn=978-0-8493-2960-9|pages=44|url=https://books.google.com/books?id=FdHevsDK3mEC&pg=PA44}} Further reading
1 : Channel access methods |
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