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arXiv · 2506.04861

Design of OTFS Signals with Pulse Shaping and Window Function for OTFS-Based Radar

Liangchen Sun·Yutaka Jitsumatsu
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Abstract

We propose a pulse radar system that employs a generalized window function derived from the root raised cosine (RRC), which relaxes the conventional constraint that the window values are within the range [0, 1]. The proposed window allows both negative values and values exceeding 1, enabling greater flexibility in signal design. The system transmits orthogonal time frequency space (OTFS) signals intermittently, establishing a flexible input-output relationship that captures both fractional delays and Doppler shifts. By combining the generalized RRC window with a rectangular pulse, the resulting pilot signal achieves a sharp concentration in the ambiguity function over both the delay and Doppler domains. To enhance the estimation accuracy of fractional parameters, we apply frequency-domain interpolation based on the autocorrelation of the RRC window, which outperforms conventional linear interpolation by preserving the signal structure more effectively.

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Liangchen Sun, Yutaka Jitsumatsu. 2025-06-05. Design of OTFS Signals with Pulse Shaping and Window Function for OTFS-Based Radar. https://arxiv.org/abs/2506.04861

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