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Transmission environment of mine laneway is non-free, wireless communication reliability is reduced by multi-path fading. MIMO can efficiently overcome multi-path fading, but MIMO channels in mine laneways have strong correlation. In this paper, the performances of space-time code in mine laneway are investigated, and the pair wise error probability (PEP) about mine laneway is analyzed. Following...
We study joint network-coding and channel-coding design to optimize delay performance. In our systems, network codes (network layer) are on top of channel codes (physical layer). Network codes run in a rateless random method, i.e., source and intermediate nodes randomly produce and transmit codewords until transmission succeeds. Thus, the rateless network codes have block-erasure-correction capability...
We propose two classes of efficiently-encodable GLDPC (EE-GLDPC) codes by generalizing the ideas of IRA and EERC codes. These GLDPC codes have performance as good as ordinary GLDPC codes. Moreover, another advantage of these EE-GLDPC codes is that they are naturally suitable for puncturing. Simulation shows that, at code length around 600, the punctured EE-GLDPC codes can outperform optimized irregular...
The instantaneous bit error rate (I-BER) is a direct representation of system performance given a particular channel realization. The I-BER knowledge enables wireless system to combat fading channel impairments by properly adapting transmission parameters. In this paper, we derive the I-BER for a bit-interleaved coded orthogonal frequency division multiplexing (BIC-OFDM) system. In high signal-to-noise...
We consider a time division duplex multiple-input multiple-output (nt × nr MIMO). Using channel state information (CSI) at the transmitter, singular value decomposition (SVD) of the channel matrix is performed. This transforms the MIMO channel into parallel subchannels, but has a low overall diversity order. Hence, we propose X-Codes which achieve a higher diversity order by pairing the subchannels,...
Abstract-In this contribution, we propose an adaptive Turbo Trellis Coded Modulation (TTCM) aided Distributed Space-Time Trellis Coding (STTC) scheme for cooperative communication over quasi-static Rayleigh fading channels. An adaptive TTCM (ATTCM) scheme is employed by the source node during the first transmission period for reliably conveying the source bits to N number of relay nodes by appropriately...
Channel estimation (CE) plays an important role in determining the achievable performance of coherently detected communications systems. In this paper, the impact of imperfect CE on Reed-Solomon coded Hybrid Automatic-Repeat-Request (ReS/H-ARQ) systems is investigated for transmission over correlated Rayleigh fading channels. The proposed scheme invokes Amplify-and-Forward relaying, where the benefits...
Cooperative diversity using distributed space-time codes has been recently proposed to form virtual antennas in order to achieve diversity gain. In this paper, we propose a distributed space-time coding with amplify-and-forward relaying. Motivated by protocol (III) presented in, we propose a distributed space-time code for an arbitrary number of relay nodes. The pairwise error probability (PEP) is...
In this paper, we consider coding schemes designed for two nodes communicating with each other with the aid of a relay node, which receives information from the two nodes in the first time slot. At the relay node we combine a powerful Superposition Coding (SPC) scheme with Iteratively-Decoded Self-Concatenated Convolutional Codes (SECCC-ID), which exchange mutual information between each other. It...
In this paper, parallel turbo phase shift keying - trellis coded modulation (Turbo PSK-TCM) schemes are designed using recursive convolutional encoders over Galois field GF(2N). These encoders are designed using the nonlinear left-circulate (LCIRC) function. The LCIRC function performs a bit left circulation over the representation word. An optimum 1-delay GF(2N) recursive convolutional encoder scheme...
This paper presents the first analysis on the energy efficiency of LT codes with Non-Coherent M-ary Frequency Shift Keying (NC-MFSK), known as green modulation, in a proactive Wireless Sensor Network (WSN) over Rayleigh flat-fading channels with path-loss. The current analysis is based on realistic parameters in the IEEE 802.15.4 standard including the effect of channel bandwidth and active mode duration...
The amplify-and-forward (AF) and the decode-and-forward (DF) cooperative coded diversity is compared with the conventional receiver coded diversity in terms of the bit error rate (BER). The comparison assumes channel coding with non-binary modulations, and fast fading channels with path-loss attenuation proportional to the distance between nodes. Numerical results obtained by extensive computer simulations...
In this paper we propose joint optimisation of soft-bit assisted iterative joint source and channel decoding with the aid of our proposed EXIT chart optimised redundant source mapping (RSM) designed for guaranteed convergence to achieve an infinitesimally low bit error ratio (BER). Data-Partitioned (DP) H.264 source coded video is used to evaluate the performance of our system employing an iterative...
In this paper, we propose a distributed space-time coded cooperative protocol with amplify-and-forward relaying. Motivated by protocol (III) presented in , we propose a distributed space-time coding for an arbitrary number of relay nodes. The pairwise error probability (PEP) is derived and the theory analysis demonstrates that our protocol achieves a diversity of order N +1 where N is the number of...
Modern wireless communication demands reliable data communication at high throughput in severe channel conditions like narrowband interference, frequency selective fading due to multipath and attenuation of high frequencies. Traditional single carrier systems address this set of problems by the use of complex, computationally intensive equalization filters. The Orthogonal Frequency Division Multiplexing...
Based on the channel sate information feedback, the performance of multi-antenna systems with adaptive modulation and space-time coding in Rayleigh fading channels is presented in this paper. The fading gain value is partitioned into a number of regions by which the modulation is adapted in terms of the region the fading gain falls in. The fading gain region boundaries for attaining maximum spectrum...
In this paper, we will investigate the block error rate (BLER) performance in cooperative communication, through combining fountain code with network coding. Contrast to the fixed-rate code, the rate of fountain code is not determined in advance, since that varies according to the instant channel state information. Under the error-free channel condition, network coding can get the maximum possible...
A conventional OFDM system often poses a stringent linearity requirement to the transmitter, especially the radio-frequency power amplifier (RFPA), to maintain its bit error rate (BER). As a result, the output power from a RFPA is often limited, thus, the communication distance is compromised. With the deployment of WiMAX (IEEE 802.16), which is targeting at the mobile market, the communication distance...
The bidirectional broadcast channel denotes a broadcast channel with two receivers where each receiver knows the message intended for the other. Exponentially decreasing upper bounds on the average error probability using maximum likelihood decoders are derived based on Gallager's results for the point-to-point channel. The bounds are coupled by the common input distribution and provide an alternative...
In this paper, a new scheme that combines Orthogonal Frequency Division Multiplexing (OFDM) with parity bit selected block spreading is introduced. In this proposed method, the data symbols in each block is used to select the spreading code. Therefore, frequency diversity in the system is increased as well as improving the symbol detection due to the inherent coding in the spreading technique. Simulation...
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