Spatiotemporal Switching Mode Design for Parallel Channel Sounding and Performance Evaluation

In this paper, a novel radio frequency (RF) switching mode for the multi-channel system based on the features of 5G air interface transmission is proposed. Traditional RF switching mode adopts the single channel to realize the Multiple-input multiple-output (Mimo) technology, hence it fails to acquire the spatial and frequency characteristics of the channel in the scenarios of time-varying. In this method, the STMicroelectronics 32-bit microcontroller single chip microcomputer (STM32 MCU) is used to generate the clock units and trigger signals, which can satisfy the synchronization of the multi-channel and generate logic levels to control RF switches which are connected to the antennas. On this basis, the proposed RF switching mode can be designed for multi-channel system to improve the measurement efficiently. According to the measured results and simulation, performing the space alternating generalized expectation-maximization (SAGE) algorithm to estimate the multipath parameters (i.e., dalay, azimuth, elevation and magnitude) and compare the estimated results with the actual scenario. The observation that the SAGE results are consistent with the characteristics of the actual channel which can demonstrate the feasibility of the switching mode.