Mitigation of crosslink interference for MIMO TDD dynamic systems in 5G+ networks

Tibhirt, Amel

Dynamic Time Division Duplexing (DynTDD) is instrumental in 5th generation (5G) networks, dynamically allocating time slots for Uplink (UL) and Downlink (DL) transmissions based on traffic demand and channel conditions. This approach enhances Spectral Efficiency (SE) and supports massive connectivity, low latency, and Quality-of-Service (QoS) requirements. However, DynTDD faces a significant challenge known as cross-link interference (CLI) when UL and DL transmissions share the same frequency bands.

The thesis aims to address CLI challenges in DynTDD through rigorous analysis and innovative methodologies. The research not only advances DynTDD technology but also pioneers solutions applicable to various communication contexts, driving interference alignment strategies across diverse scenarios.

The study explores interference alignment conditions in both centralized and distributed scenarios in Multiple-Input Multiple-Output (MIMO) systems. It addresses real-world complexities, establishing achievable Degrees of Freedom (DoF), representing the number of data streams. It focuses on optimization techniques, specifically beamforming, introduces Zero Forcing (ZF) beamforming for both DL and UL User Equipment (UE)s to align CLI in DynTDD systems. Emphasis is placed on the impact of UE-to-UE interference and improvements brought by the Weighted Minimum Mean Square Error (WMMSE) algorithms. The exploration extends to power allocation optimization using the water-filling algorithm, enhancing the overall performance and reliability of DynTDD.

Systèmes de Communication
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