Efficient carrier selection schemes for dual-carrier HSDPA system

Dual-carrier High Speed Packet Access (DC-HSPA) system has been developed as an alternative method to double data rate using more bandwidth, without use of MIMO. Since it utilizes two carriers at a time, scheduling is more important feature than a single-carrier HSPA (SC-HSPA) system. From the nature of the DC-HSPA, both carriers can be allocated to one user when the user has the highest priority on both carriers. However, if a single carrier is enough to empty the queue, one of carriers has to be selected to transmit own data, while the other carrier is assigned to the other user. Available resource on each carrier varies accordingly to the selected carrier, therefore, efficient carrier selection schemes for DC-HSPA system are proposed based on relative scheduling metric difference between users on each carrier. Simulation results show that proper carrier selection increases throughput as well as average user rate in DC-HSDPA system.