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Distributed video coding is a new paradigm for video compression based on the Slepian-Wolf and Wyner-Ziv theorems. Wyner-Ziv video coding, a lossy compression with receiver side information, enables low-complexity video encoding at the expense of a complex decoder. Most of the existing distributed video coding techniques require a feedback channel to determine the number of parity bits for decoding...
All modern communication systems use some form of forward error correction coding. Generally, coding gain is improved when soft decision decoding is used instead of hard decision decoding. While soft decision decoding is a mature technology for convolutional codes, practical soft decision decoding for the commonly used Reed-Solomon (RS) non-binary block code has only recently been developed. Most...
Diversity techniques are very effective tools to increase signal reception quality in Rayleigh fading channels. A novel space-time block coding method for cooperative relay networks is proposed which guarantees full diversity for any number of mobile relays with minimal delay, provided that few bits of feedback from the destination to the source and the relays are available. As in the case of orthogonal...
A zero forcing (ZF) decoder using the pseudo inverse of a channel matrix is generally used for detection of quasi-orthogonal space time block coding (QO-STBC). This ZF detection for QO-STBC should sacrifice not only the decoding complexity but also the diversity gain compared to a simple linear detection for orthogonal STBC schemes. This disadvantage of QO-STBC schemes are mainly result from the interference...
Four protection schemes based on RS and Raptor code as well as FEC and hybrid FEC-ARQ are analyzed and compared for erasure channels in this paper. RS code is a classic block channel code while Raptor code is a new kind of rateless code, which can produce a potentially infinite stream of packets. FEC and hybrid FEC-ARQ schemes based on RS and Raptor code are described and compared in detail. Then...
This paper proposes a joint JPEG-block coding system (JJBC) based on BCJR decoding with expurgating trellis that maintains an acceptable image quality over AWGN and wireless channels. The joint design of JPEG compression and block codes in the transmitter has the advantage of avoiding error propagation and of low decoding complexity over the conventional tandem system with separate optimization of...
With the developing of internet and wireless networks, H.264 video communication is applied more and more widely in embedded system. But, there is a troublesome problem of the decoding speed in embedded applications. In order to solve the problem, knowing which part is the most time-consuming in the decoder is important. In this paper, a method of time assessment for H.264 decoder is proposed, and...
In this paper, we investigate the performance of iterative decoding for concatenated Turbo coded and Space-time block coded (STBC) system. In our proposed system the soft parity bit needs to be estimated, which differs from traditional Turbo decoding, as the receiver adopts iterative decoding not only to Turbo codes but the entire system. In this case a simplified and effective method of parity bit...
In this paper, we present an efficient turbo-coded space time block coding (STBC) schemes in block fading channels. It has been reported that proper utilization of soft decision information is one of the important factors affecting the performance of turbo codes. If a STBC scheme is used with turbo codes, the output of the STBC decoder must be fed into a turbo code decoder in the form of soft decision...
This paper presents a novel low-complexity iterative reliability-based decoding algorithm for LDPC codes over q-ary finite fields. This proposed algorithm has low complexity and hence provides an effective trade-off between error performance and decoding complexity compared to q-ary sum product algorithm. This decoding algorithm is devised based on simple orthogonal concept of one-step majority-logic...
This paper presents the outage analysis of multiple-input multiple-output (MIMO) block-fading channels with nearest neighbour decoding and mismatched channel state information at the receiver (CSIR). Based on mismatched decoding arguments, we demonstrate the achievability of the generalised outage probability, the probability that the generalised mutual information (GMI) is less than the target data...
Multiple-input double-output (MIDO) codes are important in future wireless communications, where the portable end-user device is physically small and will typically contain maximum two receive antennas. Especially tempting is the 4×2 channel, where the four transmitters can either be all at one station, or separated between two different stations. Such channels optimally employ rate-two space-time...
In this paper, we introduce discrete memoryless Interference Channel (IFC) with two relays as two interfering transmitter-receiver pairs that are aided by two relays. We propose two different coding strategies for this channel. In the first strategy, we assume that each relay tries to mainly help one of the transmitter-receiver pairs through signal relaying and interference cancellation, while in...
There are few analytical formulas that can be used for calculating the block error rate (BLER) in block fading channels. Thus, an estimate of the BLER is often obtained using numerical methods. One such method is the threshold method which assigns 0 or 1 to the instantaneous BLER given the signal to noise ratio (SNR) level. It has been shown that utilizing such a method results in an accurate approximation...
In this paper, we describe a novel turbo encoding and iterative decoding scheme based on the concept of switched interleaving and transmission of side information. The proposed system consists of an innovative structure for turbo encoding that allows the refinement of the code words produced with the use of a codebook with different and appropriately designed interleavers. We also develop two search...
Construction of new codes by modifying (extending, puncturing, etc) a known code is a practice common when dealing with classical codes. We have shown in this paper that good codes can be obtained with these techniques, apparently not effective for fountain codes. Lengthened Luby Transform Codes have being demonstrated, trough simulation, to perform better when compared to the mother codes, under...
Geometry-adaptive block partitioning (GEO) can greatly enhance video coding efficiency but at the expense of significantly increased computational complexity. Instead of proposing fast searching algorithm for encoding only, this paper proposes to reduce the size of partitions for both the encoder and the decoder. The proposed scheme only searches partitions recognized as most valuable partitions,...
TRIDENT project was launched a few years ago by GESMA (Groupe d'Etudes Sous-Marines de l'Atlantique) in collaboration with TELECOM Bretagne. First objectives were to develop a multiple rate underwater acoustic link for images, speech signal, text and data transmission. This link was designed to provide a wireless communication to AUVs. Recently the platform was extended to low bit rate speech transmission...
Combining coding, modulation, transmit and receive diversity, and validly increases the anti-noise performance in fading channels, OSTBC (orthogonal space-time block codes) is a new channel coding technology accompanying with the extensive application of wireless communication. Based on typical channel model of the OSTBC in MIMO (multiple-in, multiple-out) wireless communication channels, a general...
Most research on distributed space-time block coding (D-STBC) has assumed that cooperative relay nodes are perfectly synchronized, for the delay destroys the required spacetime signal structure. However, in most practical distributed scenario, perfect synchronization is hard to achieve. To deal with it, this paper applies front end prefilter (FEP) as a delay synchronization scheme which accomplishes...
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