SDR processing delay estimation applying correlation detection for structure health monitoring using multi-subcarrier multiple access

Wireless and battery-less structural health monitoring (SHM) that detect structural damage at low cost are required. To achieve this, the use of multi-subcarrier multiple access (MSMA) communication method is being considered. In MSMA, time synchronization of sensing data is shifted owing to software defined radio (SDR) processing. Therefore, when an SHM monitoring method requiring time synchronization of sensing data is used, time synchronization taking SDR processing delay into account is necessary. In this study, we propose a system that estimates SDR processing delay by correlation detection and acquires time synchronization of sensing data. We measured SDR delay estimation with time accuracy by installing this system on an experimental object. Results showed that the error of the allowable processing delay estimation was different, and time synchronization can be achieved by performing sensing once by the SDR processing delay estimation method using correlation detection.