Evaluation of TDM-based Integrated Access and Backhaul Schemes for 5G and Beyond at mmWave Band

Integrated access and backhaul (IAB) has been introduced in 3GPP Release 16 as a promising enabling technology for densely deployed 5G small cell networks at millimeter wave (mmWave) band. In this paper, we study MIMO-IAB systems adopting TDM operation in the mmWave band for both single and multi-user scenarios. Throughput expressions of the MIMO-IAB system under different antenna array configurations are derived. Practical modeling of a single-panel antenna array is discussed and the model is used in the performance evaluation of the MIMO- IAB system. Simulation results demonstrate that the TDM-based MIMO-IAB systems outperform the existing non-IAB architecture in terms of throughput when proper time allocation and power allocation coefficients are selected. It is further observed that the performance of the IAB technology largely depends on how well the inter-beam interference is managed.