Computer Science – Information Theory
Scientific paper
2007-12-14
Computer Science
Information Theory
Under consideration for possible publication in IEEE Transactions on Information Theory
Scientific paper
It is well known that Space-Time Block Codes (STBCs) from orthogonal designs (ODs) are single-symbol decodable/symbol-by-symbol decodable (SSD) and are obtainable from unitary matrix representations of Clifford algebras. However, SSD codes are obtainable from designs that are not orthogonal also. Recently, two such classes of SSD codes have been studied: (i) Coordinate Interleaved Orthogonal Designs (CIODs) and (ii) Minimum-Decoding-Complexity (MDC) STBCs from Quasi-ODs (QODs). Codes from ODs, CIODs and MDC-QODs are mutually non-intersecting classes of codes. The class of CIODs have {\it non-unitary weight matrices} when written as a Linear Dispersion Code (LDC) proposed by Hassibi and Hochwald, whereas several known SSD codes including CODs have {\it unitary weight matrices}. In this paper, we obtain SSD codes with unitary weight matrices (that are not CODs) called Clifford Unitary Weight SSDs (CUW-SSDs) from matrix representations of Clifford algebras. A main result of this paper is the derivation of an achievable upper bound on the rate of any unitary weight SSD code as $\frac{a}{2^{a-1}}$ for $2^a$ antennas which is larger than that of the CODs which is $\frac{a+1}{2^a}$. It is shown that several known classes of SSD codes are CUW-SSD codes and CUW-SSD codes meet this upper bound. Also, for the codes of this paper conditions on the signal sets which ensure full-diversity and expressions for the coding gain are presented. A large class of SSD codes with non-unitary weight matrices are obtained which include CIODs as a proper subclass.
Karmakar Sanjay
Rajan Sundar B.
No associations
LandOfFree
Maximum-rate, Minimum-Decoding-Complexity STBCs from Clifford Algebras does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Maximum-rate, Minimum-Decoding-Complexity STBCs from Clifford Algebras, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Maximum-rate, Minimum-Decoding-Complexity STBCs from Clifford Algebras will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-662769