Short-Range MIMO Throughput Prediction Based on Spherical Wave Model

The exploration of Internet-of-Things (IoT) has led to widespread short-range multiple-input–multiple-output (MIMO) communications. However, traditional throughput models, limited by the far-field propagation assumptions, often fail to accurately evaluate the spatial multiplexing capability and throughput performance in short-range line-of-sight (LOS) scenarios. Against this backdrop, this letter reveals the limitations of the conventional plane wave model-based throughput model from the perspective of the effective degree of freedom (EDOF) and develops a MIMO throughput model for short-range LOS scenarios using a spherical wave model (SWM). The relationship between EDOF and throughput is analyzed and discussed. Our results show that EDOF can effectively indicate throughput variations across different transceiver layouts in short-range LOS scenarios. Throughput measurements of MIMO devices are conducted to show the superiority of the proposed SWM-based throughput model to the traditional one.