System-level analysis and evaluation of SF-DC transmit mode in HSPA+ system

Cooperated multi-point technique in HSPA⁺ system has not been paid attention until the Single Frequency Dual Cell (SF-DC) mode, where one user equipment (UE) may be served by dual NodeBs simultaneously in the single carrier frequency network, is proposed recently. In the previous research, the system-level performance with SF-DC operation had not been studied comprehensively. The main contribution of this paper is to exploit SF-DC transmit mode in the perspective of the system level and evaluate the system-level performance of SF-DC in HSPA⁺ system with different simulation scenes. The impact of SF-DC on legacy UEs and the load balancing capability of SF-DC in asymmetric loading case are investigated properly in different channel conditions. System-level simulation results show that SF-DC transmit mode performs better compared with single point transmission and the influence of SF-DC mode on legacy UEs is negligible. It also reflects that SF-DC has the ability to balance load in asymmetric loading case.