AirLive WN-300USB - Manual (Page 63)

WN-300USB v3 User’s Manual 56
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 save. 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.
16. What is GI?
GI stands for Guard Interval. It’s a measure to protect wireless devices from cross-
interference. If there are two wireless devices using the same or near channel, and they are
close enough, radio interference will occur and reduce the radio resource usability.
17. What is STBC?
STBC stands for Space-Time Block Coding, which is a technique used to transfer multiple
copies of data by multiple antenna, to improve data transfer performance. By using multiple
antennas, not only data transfer rate is improved, but also the wireless stability.
18. What is WPS?
WPS stands for Wi-Fi Protected Setup. It provides a simple way to establish unencrypted or
encrypted connections between wireless clients and access point automatically. User can
press a software or hardware button to activate WPS function, and WPS-compatible wireless
clients and access point will establish connection by themselves. There are two types of WPS
:
PBC (Push-Button Configuration) and PIN code.