I. Introduction
Joint target localization and channel estimation has become an essential technology in integrated sensing and communication (ISAC) systems [1], [2], [3]. In particular, channel estimation performance can be improved by leveraging the location parameters of the sensing targets as supplementary spatial information [4], [5], [6], [7]. As one of the representative modulation techniques in ISAC, orthogonal frequency-division multiplexing (OFDM) provides reliable target localization and channel estimation in low-velocity scenarios [8], [9]. However, in high-mobility scenarios such as the Internet of vehicles and unmanned aerial vehicle (UAV) swarms, Doppler spread caused by moving targets disrupts subcarrier orthogonality [10], [11], making it challenging to accurately capture the channel response in OFDM-based ISAC systems.