A Framework for Evaluating Mobile-to-Mobile Inter-System Interference with Hotspot Considerations for WiMAX TDD Coexistence

This paper proposes a framework for evaluating mobile-to-mobile inter-system interference which occurs between two time division duplex (TDD) WiMAX systems deployed in adjacent frequency blocks and the same geographical area. The need for a new framework arises from inability of the traditional approaches to capture several important factors, such as power control and non-uniform user distribution because of high user density areas (hotspots). Accounting for these aspects becomes essential for accurately quantifying the effect of mobile-to-mobile interference for the purpose of spectrum engineering and system deployment. Based on the proposed framework, the quantitative per user performance degradation was obtained and we are also able to analyze the impact of guard band, frequency coordination between systems and partial synchronization on mobile-to-mobile interference.