MicroNet Technology SP907NL - Manual (Page 50)

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13. What is Spread Spectrum?
Spread Spectrum technology is a wideband radio frequency technique developed
by the military for use in reliable, secure, mission-critical communication systems.
It is designed to trade off bandwidth efficiency for reliability, integrity, and security.
In other words, more bandwidth is consumed than in the case of narrowband
transmission, but the trade off produces a signal that is, in effect, louder and thus
easier to detect, provided that the receiver knows the parameters of the spread-
spectrum signal being broadcast. If a receiver is not tuned to the right frequency, a
spread-spectrum signal looks like background noise. There are two main
alternatives, Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping
Spread Spectrum (FHSS).
14. What is WMM?
Wi-Fi Multimedia (WMM), a group of features for wireless networks that improve
the user experience for audio, video and voice applications. WMM is based on a
subset of the IEEE 802.11e WLAN QoS draft standard. WMM adds prioritized
capabilities to Wi-Fi networks and optimizes their performance when multiple
concurring applications, each with different latency and throughput requirements,
compete for network resources. By using WMM, end-user satisfaction is
maintained in a wider variety of environments and traffic conditions. WMM makes it
possible for home network users and enterprise network managers to decide which
data streams are most important and assign them a higher traffic priority.
15. What is WMM Power Save?
WMM Power Save is a set of features for Wi-Fi networks that increase the
efficiency and flexibility of data transmission in order to conserve power. WMM
Power Save has been optimized for mobile devices running latency-sensitive
applications such as voice, audio, or video, but can benefit any Wi-Fi device. WMM
Power Save uses mechanisms included in the IEEE 802.11e standard and is an
enhancement of IEEE 802.11 legacy power saves. With WMM Power Save, the
same amount of data can be transmitted in a shorter time while allowing the Wi-Fi
device to remain longer in a low-power “dozing” state.