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Convolutional Space-Time Codes
2006 Canadian Conference on Electrical and Computer Engineering, 2006Space-time codes are usually generated using a generator matrix with 2 columns and mod 4 operations for QPSK modulation with two transmit antennas. A Z4 convolutional code has also been used to represent these space-time codes. Another way of representing them is to use a conventional binary convolutional code of rate 2/4.
David Bernier, François Chan
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Proceedings. International Symposium on Information Theory, 2005. ISIT 2005., 2005
Rateless codes are good codes of infinite length that have the property that prefixes of such codes are themselves good codes. This makes them attractive for applications in which the channel quality is uncertain, where systems transmit as much of a codeword as necessary for decoding to be possible.
Uri Erez +2 more
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Rateless codes are good codes of infinite length that have the property that prefixes of such codes are themselves good codes. This makes them attractive for applications in which the channel quality is uncertain, where systems transmit as much of a codeword as necessary for decoding to be possible.
Uri Erez +2 more
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On the performance of space-time codes
Proceedings of the IEEE Information Theory Workshop, 2003This paper provides an overview of the results in a recent journal submission by the same authors. The first part of that paper studies the pairwise error probability of codewords (PEP) of a space-time code over a quasistatic channel, using an approach that allows both known and unknown channel cases to be considered simultaneously.
Hsiao-feng Lu +3 more
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Concatenated space-time coding
12th IEEE International Symposium on Personal, Indoor and Mobile Radio Communications. PIMRC 2001. Proceedings (Cat. No.01TH8598), 2002The serial concatenation of standard convolutional codes with differential space-time modulation is considered for fast flat fading multiple antenna channels. Decoding is performed iteratively by passing symbol-wise a-posteriori probability information between the decoders of the inner space-time code and the outer convolutional code.
Christian Schlegel, Alex J. Grant
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IEEE Transactions on Information Theory, 2003
Summary: A universal framework is developed for constructing full-rate and full-diversity coherent space-time codes for systems with arbitrary numbers of transmit and receive antennas. The proposed framework combines space-time layering concepts with algebraic component codes optimized for single-input-single-output (SISO) channels. Each component code
Hesham El Gamal, Mohamed Oussama Damen
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Summary: A universal framework is developed for constructing full-rate and full-diversity coherent space-time codes for systems with arbitrary numbers of transmit and receive antennas. The proposed framework combines space-time layering concepts with algebraic component codes optimized for single-input-single-output (SISO) channels. Each component code
Hesham El Gamal, Mohamed Oussama Damen
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Physical Review, 1969
It is known that the entire geometry of many relativistic space-times can be summed up in two concepts, a space-time measure $\ensuremath{\mu}$ and a space-time causal or chronological order relation $C$, defining a causal measure space. On grounds of finiteness, unity, and symmetry, we argue that macroscopic space-time may be the classical-geometrical
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It is known that the entire geometry of many relativistic space-times can be summed up in two concepts, a space-time measure $\ensuremath{\mu}$ and a space-time causal or chronological order relation $C$, defining a causal measure space. On grounds of finiteness, unity, and symmetry, we argue that macroscopic space-time may be the classical-geometrical
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Lattice code decoder for space-time codes
IEEE Communications Letters, 2000We explore the lattice sphere packing representation of a multi-antenna system and the algebraic space-time (ST) codes. We apply the sphere decoding (SD) algorithm to the resulted lattice code. For the uncoded system, SD yields, with small increase in complexity, a huge improvement over the well-known V-BLAST detection algorithm.
Mohamed Oussama Damen +2 more
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Effective Coding Gain for Space-Time Codes
2006 IEEE International Symposium on Information Theory, 2006The performance of space-time codes is evaluated in terms of diversity gain and coding gain, two measures which describe the worst-case pairwise error probability between codewords at high signal-to-noise ratio (SNR). We introduce the concept of effective coding gain to provide an estimate on the bit error rate (BER) at low-to-moderate SNR.
Jimmy Chui, A. Robert Calderbank
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IEEE Transactions on Wireless Communications, 2003
It is shown that the separation between space-time code matrices can be described in terms of a metric of Euclidean type, which is defined via the singular values of difference code matrices, and arises naturally from a minimization of the pairwise error probability.
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It is shown that the separation between space-time code matrices can be described in terms of a metric of Euclidean type, which is defined via the singular values of difference code matrices, and arises naturally from a minimization of the pairwise error probability.
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On orthogonal designs and space-time codes
Proceedings IEEE International Symposium on Information Theory,, 2003Two aspects of orthogonal designs are explored in this paper. The first relates to the existence of restricted-alphabet orthogonal designs. While orthogonal designs yield efficient space-time codes, real orthogonal designs exist only for sizes n=2, 4, 8.
Hsiao-feng Lu +2 more
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