Time-Modulated Arrays in Scanning Mode Using Wideband Signals for Range-Doppler Estimation With Time-Frequency Filtering and Fusion

Time-modulated array (TMA) has garnered significant interest in recent years as an alternative to phased arrays for certain applications. The TMA offer advantages such as simplicity and high accuracy when employed in scanning mode. However, a significant limitation of TMA is the constrained signal bandwidth, which must be lower than the modulation frequency to avoid aliasing. This constraint can impede progress in wideband range-Doppler (RD) estimation. To address this problem, this article proposes a TMA structure and signal processing method that integrates time, frequency, and time–frequency (TF) domains to extract information for RD estimation. The proposed methods effectively overcome the bandwidth limitation by utilizing TF filtering and data fusion techniques, thereby enhancing the performance of RD estimation in TMA. The simulation results validate the effectiveness of the proposed strategies.