Preemption and QoS management algorithms for coordinated and uncoordinated base stations

摘要

This paper addresses the problem of resource allocation and qualityudof service (QoS) management in a downlink communication systemudwhere the users are allowed to be attached to and receive dataudfrom one or several cooperating base stations (BSs) under orthogonaludfrequency division multiple access (OFDMA). Under the assumptionudthat only information regarding the link path loss is availableudat each transmitter, the problem of power and bandwidth allocationudto minimize transmission power subject to minimum rate (i.e., QoS)udconstraints is written as a convex optimization problem. Consideringudthat the transmission power per BS is limited, the Lagrangeudmultipliers of the optimization problem are exploited either to ef-udficiently identify which are the candidates to be preempted wheneverudunaffordable power consumption arises, or to relax the targetudrate constraints for the ongoing connections. In the second case,udthe Lagrange multipliers are used in combination with the NewtonRaphsonudalgorithm to adjust the QoS of the users in the system accordingudto the available BS power.