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Wireless ATM has been proposed for next-generation personal
communicationnetworks (PCN) to support the integrated multimedia
communication services.Guaranteed quality of service (QOS) is
required for the Wireless ATM networksto support multimedia
communications. However, emerging standards, such as the IEEE
802.11 Wireless LAN, are designed to provide wireless access in
a conventional way without considering QOS provision. In this
paper, we presentan important system design issue for wireless
ATM networks in general, is thedesign of an advanced medium
access control (MAC) protocol for supporting allATM QoS
requirements for heterogeneous traffic. In the past, the
typical MAC protocols of wireless ATM are based on FDMA,CDMA and
TDMA. Most previous MAC protocols in the area use an adaptive
TDMAscheme, due to its ability to flexibly accommodate a
connection's bit rateneeds by allocating more or fewer time
slots depending on current trafficconditions. There are two main
categories used in the TDMA scheme are"contention" and
"reservation". These contention-based protocols (like IEEE
802.11) attain good performanceunder light traffic, basically
due to the short delays when the number ofcollision is limited.
The reservation-based protocols (like MDR-TDMA) are morecomplex
and introduce some extra delays due to the required reservation
phase.Their performance depends to a large extent on the
scheduling mechanism usedfor the allocation of the available
bandwidth. Thus, we propose a novel guaranteed QOS MAC
protocol with Dynamic WeightedEarliest Deadline First with Save
and Borrow (DWEDF/SB) scheduling mechanismfor wireless ATM
network. The MAC protocol can provide low latency,
fairnessthroughput, low cell loss ratio and efficient channel
utilization for QoSguaranteed.
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