Optimal Partially Superimposed Pilot Pattern for OTFS Communication

This paper tackles the intricate challenge of channel estimation (CE) and symbol detection in high-mobility scenarios for orthogonal time frequency space (OTFS) systems. We introduce a novel partially superimposed pilots (PSP) pattern, strategically balancing computational complexity and CE accuracy by partially superimposing pilots and data symbols in the delay-Doppler (DD) domain. Additionally, we propose a CE and symbol detection (CESD) algorithm, employing an iterative approach that combines low complexity minimum mean squared error (LMMSE) for CE and simplicity-based detection for data symbols. Key contributions encompass optimal pilot pattern determination, a comprehensive iterative algorithm, and a thorough performance evaluation. Comparative analyses with state-of-the-art methods underscore the superior trade-off achieved by CESD in terms of normalized mean square error for CE, bit error rate, spectral efficiency, and computational complexity.