A Multi-Beam XL-MIMO Testbed Based on Hybrid CPU-FPGA Architecture

To support more users and higher data rates in future communication networks, the extremely large-scale massive multiple-input multiple-output (XL-MIMO) is considered a promising technique. The booming research on XL-MIMO necessitates a reconfigurable XL-MIMO testbed that can be used to validate new research ideas in real wireless environments and collect data for XL-MIMO channel characteristics analysis. To provide such a reliable and convenient testbed, we designed a multi-beam XL-MIMO testbed based on the hybrid CPU-FPGA architecture and channel calibration schemes. The ability to customize modules makes our testbed a convenient verification platform for future communication systems. Moreover, numerous trial measurement results in the indoor near-field scenario with moderate user equipment (UE) mobility are presented, and the excellent performance indicates that our testbed is an ideal platform for the evaluation of XL-MIMO-related algorithms.