A Hybrid Approach of Time-Frequency Domain Interference Coordination for QoS Guarantee in Macro-Femto Co-Channel Deployment

Femto is introduced to enhance the indoor coverage and the system capacity in LTE-Advanced system. Some methods, such as time domain interference coordination (TDIC) and frequency domain interference coordination (FDIC), have been discussed to deal with the interference between macro and femto cell when they are deployed in co- channel manner. However, TDIC operates well even though the system load is heavy but it cannot offer enough throughput in certain scenarios. On the contrary, FDIC could offer high throughput under light-load conditions at the cost of much more bandwidth. Combined the advantages of TDIC and FDIC, an approach of hybrid domain interference coordination (HDIC) is proposed and a greedy algorithm is designed in this paper. Moreover, different to the pure TDIC, TDIC used in HDIC is enhanced by allowing the user hopping to a better carrier to cooperate, namely carrier selective TDIC (CS-TDIC). Simulations show that HDIC could improve the average throughput of system in the case of light load and enable more users to meet their QoS demand of services when the load is heavy.