Low-complexity medium access control protocols for QoS support in third-generation radio access networksud

摘要

One approach to maximizing the efficiency ofudmedium access control (MAC) on the uplink in a future widebandudcode-division multiple-access (WCDMA)-based third-generationudradio access network, and hence maximize spectral efficiency,udis to employ a low-complexity distributed scheduling controludapproach. The maximization of spectral efficiency in third-generationudradio access networks is complicated by the need toudprovide bandwidth-on-demand to diverse services characterizedudby diverse quality of service (QoS) requirements in an interferenceudlimited environment. However, the ability to exploit the fulludpotential of resource allocation algorithms in third-generationudradio access networks has been limited by the absence of a metricudthat captures the two-dimensional radio resource requirement,udin terms of power and bandwidth, in the third-generation radioudaccess network environment, where different users may haveuddifferent signal-to-interference ratio requirements. This paperudpresents a novel resource metric as a solution to this fundamentaludproblem. Also, a novel deadline-driven backoff procedure hasudbeen presented as the backoff scheme of the proposed distributedudscheduling MAC protocols to enable the efficient support ofudservices with QoS imposed delay constraints without the needudfor centralized scheduling. The main conclusion is that low-complexityuddistributed scheduling control strategies using overloadudavoidance/overload detection can be designed using the proposedudresource metric to give near optimal performance and thus maintainuda high spectral efficiency in third-generation radio accessudnetworks and that importantly overload detection is superior toudoverload avoidance.