Truncated Turbo Equalizer with SIC for OTFS

• DOI: 10.48550/arxiv.2305.14966
• Publication Date: 2023-01-01
• Authors: P. S. Sanoopkumar; Stephen McWade; Arman Farhang
• Keywords: Turbo; Turbo equalizer; Benchmark (surveying)

Orthogonal time frequency space (OTFS) is a promising candidate waveform for the next generation wireless communication systems. OTFS places data in delay-Doppler (DD) domain, which simplifies channel estimation highmobility scenarios. However, due to 2-D convolution effect of time-varying DD equalization still challenge OTFS. Existing equalizers are either highly complex or they do not consider intercarrier interference present high-mobility Hence, this paper, we propose novel two-stage detection technique coded Our proposed detector brings orders magnitude computational complexity reduction compared existing methods. At first stage, it truncates by considering only significant coefficients along Doppler dimension and performs turbo equalization. To reduce load equalizer, our method deploys modified LSQR (mLSQR) algorithm. second with two successive cancellation (SIC) iterations, removes residual caused truncation. evaluate performance truncated equalizer SIC (TTE-SIC), set minimum mean squared error (MMSE) without truncation as benchmark. simulation results show that TTE-SIC achieves about same bit rate (BER)