Quadrature-division multiple access

This article includes a list of general references, but it lacks sufficient corresponding inline citations. Please help to improve this article by introducing more precise citations. (July 2010) (Learn how and when to remove this message)

Quadrature-division multiple access (QDMA) is a radio protocol.^[1] The term combines two standard terms in telecommunications, CDMA and QPSK.

QDMA 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.

This section does not cite any sources. Please help improve this section by adding citations to reliable sources. Unsourced material may be challenged and removed. (July 2010) (Learn how and when to remove this message)

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.

• John G. Proakis, Digital Communications, Third Edition, McGraw-Hill, ISBN 0-07-051726-6
• Ulrich L. Rohde, Jerry Whitaker, T. T. N. Bucher, Communications Receivers, Second Edition, McGraw-Hill, ISBN 0-07-053608-2

This article related to radio is a stub. You can help Wikipedia by expanding it.

• v
• t
• e