Load Balancing with Reduced Unnecessary Handoff in Hierarchical Macro/Femto-cell WiMAX Networks

The hierarchical macro/femto cell WiMAX networks are observed to be quite promising for mobile operators as it improves their network coverage and capacity at the outskirt of the macro cell. However, this new technology introduces increased number of macro/femto handoff which inturn may affect the system performance. Users moving with high velocity or undergoing real-time transmission suffers degraded performace due to huge number of unnecessary macro/femto handoff. Our proposed handoff decision algorithm eliminates the unnecessary handoff while balancing the load of the macro and femto cells. The performance of the proposed algorithm is analyzed using Continuous Time Markov Chain (CTMC) Model. In addition, we have also contributed a method to determine the balanced threshold level of the received signal strength (RSS) from macro base station (BS). The balanced threshold level provides equal load distribution to the macro and femto BSs. The balanced threshold level is evaluated based on the distant location of the femto cells for small scaled networks. Numerical analysis shows that threshold level above the balanced threhold results in higher load distribution to the femto BSs.