Spread Spectrum Multiple Access(SSMA) PPT PDF Seminar Report
Code Division Spread Spectrum is one form of CDMA communication technique optimized for the cost conscious, high volume and short cycle consumer electronics market. Its primary application is in digital cordless telephony today. Meanwhile, it is being applied to wireless devices for the last 100-meter connection to the Internet, and in the wireless local loop to provide sub-$20 handset cost, tariff free mobile voice services in some third world countries.
Why is CD/SS technology suitable for consumer electronics? And how does it compare to other long-range wireless transmission techniques such as DSS and Wide band CDMA? This report will introduce the history, theory and practice, and highlight some technical areas for comparison. Consumer electronics are, by heritage, an “Open Architecture” market. All forms of technology finds its niche, which eventually help every other technology. This philosophy drives the Lanwave view of this market, and forms the cornerstone to our business approach from sales to research and engineering.
Spread spectrum multiple access (SSMA) uses signals which have a transmission bandwidth that is several orders of magnitude greater than the minimum required RF bandwidth. A pseudo noise (PN) sequence converts a narrow band signal to a wideband noise like signal before transmission. SSMA also provides immunity to multipath interference and robust multiple access capability. Spread spectrum multiple access is not very bandwidth efficient when used by a single user.
However, since many users can share the same spread spectrum bandwidth without interfering with one another, Spread spectrum systems become bandwidth efficient in multiple user environment. It is exactly this situation which is of interest to wireless system designers.