1 research outputs found
A New Family of Low-Complexity Decodable STBCs for Four Transmit Antennas
In this paper we propose a new construction method for rate-1
Fast-Group-Decodable (FGD) Space-Time-Block Codes (STBC)s for 2^a transmit
antennas. We focus on the case of a=2 and we show that the new FGD rate-1 code
has the lowest worst-case decoding complexity among existing comparable STBCs.
The coding gain of the new rate-1 code is then optimized through constellation
stretching and proved to be constant irrespective of the underlying QAM
constellation prior to normalization. In a second step, we propose a new rate-2
STBC that multiplexes two of our rate-1 codes by the means of a unitary matrix.
A compromise between rate and complexity is then obtained through puncturing
our rate-2 code giving rise to a new rate-3/2 code. The proposed codes are
compared to existing codes in the literature and simulation results show that
our rate-3/2 code has a lower average decoding complexity while our rate-2 code
maintains its lower average decoding complexity in the low SNR region at the
expense of a small performance loss.Comment: 5 pages, 4 figures and 1 table. Accepted for publication in IEEE
International Conference on Communications (ICC 2012), 201