Block Layering Approach in TAST Codes

Zahoor Ahmed, Jean Pierre Cances, Vahid Meghdadi

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DOI: 10.4236/ijcns.2010.310105                

Abstract

Threaded Algebraic Space Time (TAST) codes developed by Gamal et al. is a powerful class of space time codes in which different layers are combined and separated by appropriate Diophantine number . In this paper we introduce a technique of block layering in TAST codes, in which a series of layers (we call it Block layers) has more than one transmit antenna at the same time instant. As a result we use fewer layers (Diophantine numbers) for the four transmit antennas scheme, which enhances the coding gain of our proposed scheme. In each block layer we incorporate Alamouti’s transmit diversity scheme which decreases the decoding complexity. The proposed code achieves a normalized rate of 2 symbol/s. Simulation result shows that this type of codes outperforms TAST codes in certain scenarios.

Keywords

TAST Code, Block Layer, Space Time Coding

Conflicts of Interest

The authors declare no conflicts of interest.

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