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Space-time codes with controllable ML decoding complexity for any number of transmit antennas

Naresh Sharma·Pavan R. Pinnamraju·Constantinos B. Papadias
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Abstract

We construct a class of linear space-time block codes for any number of transmit antennas that have controllable ML decoding complexity with a maximum rate of 1 symbol per channel use. The decoding complexity for $M$ transmit antennas can be varied from ML decoding of $2^{\lceil \log_2M \rceil -1}$ symbols together to single symbol ML decoding. For ML decoding of $2^{\lceil \log_2M \rceil - n}$ ($n=1,2,...$) symbols together, a diversity of $\min(M,2^{\lceil \log_2M \rceil-n+1})$ can be achieved. Numerical results show that the performance of the constructed code when $2^{\lceil \log_2M \rceil-1}$ symbols are decoded together is quite close to the performance of ideal rate-1 orthogonal codes (that are non-existent for more than 2 transmit antennas).

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Naresh Sharma, Pavan R. Pinnamraju, Constantinos B. Papadias. 2007-04-23. Space-time codes with controllable ML decoding complexity for any number of transmit antennas. https://doi.org/10.1109/isit.2007.4557660

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