Self-Optimization Algorithm for Inter-RAT Configuration Parameters

The increase in demand for wireless data communication has incited mobile operators to deploy new radio access technologies (RATs) overlaying with legacy ones. Flexible usage of multiple RATs and trouble-free inter-RAT operation require the optimization of the configuration parameters of different RATs. One approach to optimize these parameters is to try different default network-wide settings for all cells and apply the best in terms of network performance. Another approach is to manually optimize the parameters of the cells having problems with the aid of drive tests and expert knowledge. The major problem with these two approaches is that they require human intervention and increase operational expenditures. In this paper, a general and decentralized self-optimizing algorithm for the inter-RAT configuration parameters is proposed. The algorithm optimizes the configuration parameters on a cell-pair basis and runs only in the base stations of the newly installed RAT. As a testing use case, the proposed algorithm is applied to optimize the configuration parameters related to inter-RAT mobility handovers. Simulation results have shown that the proposed optimization algorithm outperforms the default network-wide settings and converges to a stable operation point that significantly improves the network performance.