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The super codes of the first order Reed-Muller code are widely used in the practical wireless communication systems, such as WCDMA and LTE. However, the super codes are usually obtained by exhaustive computer search, which involves huge computational cost. Therefore a systematic algorithm to construct the super codes beyond exhaustive computer search has been expected for long time. In this paper,...
This study discussed the decoding mechanism of block product turbo code (BPTC) (196,96) and analyzed its efficiency, used the Hamming (15,11) and Hamming (13,9) block channel code combinations and block interleaving to construct a BPSK modulation and BPTC (196,96) coding system in the concept of feedback encoding in turbo code. The system is based on the Analog Device DSP platform, the C code is used...
We investigate turbo coded bit interleaved coded modulation (BICM) schemes for multiple-input multiple-output (MIMO) block-fading channels. Both serial and parallel concatenated turbo codes are considered and their performance is compared. A sphere decoder is employed to achieve good performance with reduced computation complexity when the size of the constellation or the number of transmit antenna...
Turbo code and Low Density Parity Check (LDPC) code are both recommended as FEC code in many communication standards owing to their impressive error correcting performance. Aiming at the common architecture which can decode both of the two codes, this paper describes the method of decoding turbo codes with message passing algorithm which is conventionally used for LDPC codes. In this method, turbo...
Flash memory is a non-volatile computer storage device which consists of blocks of cells. While increasing the voltage level of a single cell is fast and simple, reducing the level of a cell requires the erasing of the entire block containing the cell. Since block-erasures are costly, traditional flash coding schemes have been developed to maximize the number of writes before a block-erasure is needed...
It has previously been shown that ensembles of terminated protograph-based low-density parity-check (LDPC) convolutional codes have a typical minimum distance that grows linearly with block length and that they are capable of achieving capacity approaching iterative decoding thresholds on the binary erasure channel (BEC). In this paper, we review a recent result that the dramatic threshold improvement...
A collection of slides from the author's conference presentation is given. The following topics are discussed: low-density parity-check code; iterative decoding; demodulation; optimization; irregular LDPC code; and binary message passing algorithm.
JPEG2000 image compression system consists of two main algorithms namely, discrete wavelet transform (DWT) and embedded block coding with optimized truncation (EBCOT). These algorithms are compute intensive and require efficient VLSI implementation for real time applications. Bit plane coder (BPC) and MQ coder are the two cores of the EBCOT algorithm. All processes to be executed by the MQ coder are...
It is known that the Luby Transform codes provide an efficient scheme to transfer information over erasure channels. These codes are also rate-less and robust against packet losses in a jamming environment. In this paper overcome many weaknesses that this coding technique apprehends. Three weaknesses are observed in three different categories when the equivalent matrix is employed. In fact, such codes...
We present and evaluate a new multiple-description coding extension to the international standard for pulse code modulation speech coding (ITU-T Rec. G.711). This extension is inserted between the G.711 encoder and decoder. It uses speech-polarity decomposition to spread the speech signal across two channels thus increasing robustness to channel losses. When both channels deliver their payloads the...
In this paper, we propose a systematic design of space-time block codes (STBC) which can achieve high rate and full diversity when the partial interference cancellation (PIC) group decoding is used at receivers. The proposed codes can be applied to any number of transmit antennas and admit a low decoding complexity while achieving full diversity. For M transmit antennas, in each codeword real and...
We present a channel-matched coding method for the compensation of dispersion in coarsely quantized coherent optical communication systems. The approach consists in optimizing a subset of equiprobable input symbols for each channel state, which is robust against dispersion and coarse quantization. This codebook optimization is solved efficiently using an iterative algorithm. The performance of the...
For a family/sequence of Space-Time Block Codes (STBCs) C1, C2, ..., with increasing number of transmit antennas Ni, with rates Ri complex symbols per channel use, i = 1, 2,..., the asymptotic normalized rate is defined as limi→∞ Ri/Ni. A family of STBCs is said to be asymptotically-good if the asymptotic normalized rate is non-zero, i.e., when the rate scales as a nonzero fraction of the number of...
In this paper, we present new constructions of quasi-orthogonal space-time block codes for 4 and 6 transmit antennas. The proposed codes possess the following properties: full-rate, full transmit diversity, even power distribution and low decoding complexity, which make these two codes very practical spacetime coding schemes. For the case of 4 transmit antennas, the code can be decoded pair-by-pair,...
We propose two encoding strategies for a two user cooperative Orthogonal Frequency Division Multiple Access (OFDMA) system, based on block Markov superposition encoding. We obtain the expressions for the resulting achievable rate regions for both encoding strategies, and evaluate them through simulations. We show that, by allowing for re-partitioning and re-encoding of the cooperative messages across...
This paper investigates non-binary low-density parity-check (LDPC) erasure correcting codes suitable to guarantee reliable transmission in wireless communications systems. In particular, irregular repeat-accumulate (IRA) codes are considered, characterized by linear-time encoding complexity. The performance of non-binary IRA codes is compared with their binary counterparts on the packet erasure channel...
The two user Gaussian interference channel with a full-duplex relay is studied. By using genie aided approaches, two new upper bounds on the achievable sum-rate in this setup are derived. These upper bounds are shown to be tighter than previously known bounds under some conditions. Moreover, a transmit strategy for this setup is proposed. This strategy utilizes the following elements: Block Markov...
We address the problem of constructing practical coding schemes for Integer-Forcing (IF) equalization. Previously proposed IF schemes suggested the use of nested lattice codes or linear block codes over Zq. While such codes have good properties from a theoretic point of view, their implementation complexity may become significant when q is large. In this work we show that at high transmission rates,...
The block fading channel model is very useful for many systems in urban environments. When striving for high performance implying high rate, full-diversity and excellent coding gain, coded modulations have to be used. When linear precoding is used, error-correcting codes can focus on achieving a high coding gain and are not constrained in coding rate so that no bandwidth is sacrificed. However, optimal...
In this paper, we propose a low-complexity multiple-parallel-concatenated (MPC) coding scheme for magnetic recording systems, where a high-rate quasi-cyclic (QC) low-density parity-check (LDPC) code with column weight 2 based on the Balanced Incomplete Block Design (BIBD) construction is used as the component code. Simulation results show that the proposed scheme improves the error floor performance...
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