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Another
approach, based on previous work made on wireless ATM*, led to a new
WLAN standard: HiperLAN/2*,
promoted by ETSI/BRAN* (MMAC* has issued a sister standard in Japan:
HiSWANa*). HiperLAN/2
embeds QoS* features that enable it to go beyond the limitations of
other wireless systems and to widen the application field of WLANs.
These mechanisms include:
Dynamic Link Adaptation: modulation scheme is dynamically selected among a set of 7 different modes depending on the radio link conditions Power
Control: radio transmission power level can be dynamically adapted
to the radio link conditions
Packet transmission scheduling:
resource is allocated to applications in a fair manner according
to their needs
Flexible
and efficient error control:
Low latency
automatic retransmission: lost data are quickly and
efficiently retransmitted
Forward Error Control scheme for very low delay demanding applications HiperLAN/2 also includes a set of Convergence Layers that makes it an efficient access technology to various networks: IEEE 1394, Ethernet, ATM, UMTS, IP. Taking advantage of these characteristics, HiperLAN/2 is able to support QoS demanding applications such as high quality video streaming (DVD-like) and interactive multimedia services (videoconferencing, voice calls) in a wide range of environments.
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