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arXiv · 1104.1155

Modulation Diversity in Fading Channels with Quantized Receiver

Saif Khan Mohammed·Emanuele Viterbo·Yi Hong·Ananthanarayanan Chockalingam
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Abstract

In this paper, we address the design of codes which achieve modulation diversity in block fading single-input single-output (SISO) channels with signal quantization at receiver and low-complexity decoding. With an unquantized receiver, coding based on algebraic rotations is known to achieve modulation coding diversity. On the other hand, with a quantized receiver, algebraic rotations may not guarantee diversity. Through analysis, we propose specific rotations which result in the codewords having equidistant component-wise projections. We show that the proposed coding scheme achieves maximum modulation diversity with a low-complexity minimum distance decoder and perfect channel knowledge. Relaxing the perfect channel knowledge assumption we propose a novel training/estimation and receiver control technique to estimate the channel. We show that our coding/training/estimation scheme and minimum distance decoding achieve an error probability performance similar to that achieved with perfect channel knowledge.

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Saif Khan Mohammed, Emanuele Viterbo, Yi Hong, Ananthanarayanan Chockalingam. 2011-04-06. Modulation Diversity in Fading Channels with Quantized Receiver. https://arxiv.org/abs/1104.1155

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