Low Complexity LMMSE Receiver for OTFS

Shashank Tiwari; Suvra Sekhar das; Vivek Rangamgari

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arXiv · 1910.01350

Low Complexity LMMSE Receiver for OTFS

Shashank Tiwari·Suvra Sekhar das·Vivek Rangamgari

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Abstract

Orthogonal time frequency space modulation is a two dimensional (2D) delay-Doppler domain waveform. It uses inverse symplectic Fourier transform (ISFFT) to spread the signal in time-frequency domain. To extract diversity gain from 2D spreaded signal, advanced receivers are required. In this work, we investigate a low complexity linear minimum mean square error receiver which exploits sparsity and quasi-banded structure of matrices involved in the demodulation process which results in a log-linear order of complexity without any performance degradation of BER.

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Shashank Tiwari, Suvra Sekhar das, Vivek Rangamgari. 2019-10-03. Low Complexity LMMSE Receiver for OTFS. https://arxiv.org/abs/1910.01350

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