Reduced ML-Decoding Complexity, Full-Rate STBCs for $2^a$ Transmit Antenna Systems

— For an nt transmit, nr receive antenna system (nt × nr system), a full-rate space time block code (STBC) transmits nmin = min(nt, nr) complex symbols per channel use and in general, has an ML-decoding complexity of the order of Mntnmin (considering square designs), where M is the constellation size. In this paper, a scheme to obtain a fullrate STBC for 2a transmit antennas and any nr, with reduced ML-decoding complexity of the order of Mnt(nmin− 3 4 )−0.5 , is presented. The well known Silver code for 2 transmit antennas is a special case of the proposed scheme. Further, it is shown that the codes constructed using the scheme have higher ergodic capacity than the well known punctured Perfect codes for nr < nt. Simulation results of the symbol error rates are shown for 8 × 2 systems, where the comparison of the proposed code is with the punctured Perfect code for 8 transmit antennas. The proposed code matches the punctured Perfect code in error performance, while having red...

• Type: Journal
• Year: 2010
• Where: CORR
• Authors: K. Pavan Srinath, B. Sundar Rajan
• Keywords: Code, CORR 2010, Education, ML-decoding Complexity, Perfect Code