A dynamic CRE and ABS scheme for enhancing network capacity in LTE-advanced heterogeneous networks

With the ever-growing popularity of wireless multimedia services, wireless network base stations are increasingly likely to overload in high population density areas. An economical means exists for operators to establish more picocells in order to reduce the user traffic load on base stations and increase system capacity; however, inter-cell interference is a challenge in such heterogeneous networks. This study proposes a novel scheme that integrates dynamic cell range expansion (CRE) and dynamic almost blank subframe (ABS) schemes based on 3GPP R10 eICIC. The proposed scheme can automatically adjust the CRE bias value according to the cell traffic load, thereby ensuring that users have access to sufficient resources to transmit data when they are offloaded to a smaller cell. Furthermore, the proposed ABS scheme can determine the ABS ratio that yields the highest system capacity. The proposed CRE scheme ensures that offloaded users always have access to sufficient resources. The proposed CRE and ABS scheme can improve network system capacity by more than 13.9% of 3GPP R10 and 11.7% of the competing algorithm.