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The performance of lattice codes in the additive white Gaussian noise (AWGN) channel has attracted much attention lately, however, their performance under ergodic fading channels has been relatively unexplored. We show that lattice coding and decoding achieve the capacity of the ergodic point-to-point and multiple-access channels (MAC). Additionally, a low-complexity scheme is proposed for the ergodic...
A new scheme for error-free transmission is presented which uses optimized combination of adaptive modulation and coding (AMC) and automatic repeat request (ARQ). Using conventional error correction codes with finite length, a limited value of packet error rate (PER) is inevitable. More powerful codes with more extra parity bits results in lower PER, however, at the cost of more transmit power per...
Cooperative transmission is a convenient means of generating spatial diversity without the need of collocating multiple antennas in a single terminal. In this paper, the asymptotic diversity properties of a cooperative transmission system are investigated. The analysis is carried out for an amplify-and-forward multi-relay protocol implementing a distributed randomized space-time block code. According...
Adaptive modulation and coding (AMC) transmission of wireless communications requires accurate channel state information (CSI) to select the suitable transmission mode. However, the accurate CSI is hard to be obtained for high-speed railway (HSR) communications due to the fast time-varying fading channel, which strictly limits the performance of HSR with AMC transmission. Recent studies show that...
The performance of Binary Phase Shift Keying (BPSK) in a Joint fading and Two-path Shadowing (JFTS)environment is analyzed. Closed form expression for the exact Average Bit Error Rate (ABER) of coherent BPSK scheme is presented using the Moment Generating Function (MGF) of the JFTS distribution. Finally the coherent BPSK ABER of a wireless communication system is simulated over JFTS fading / shadowing...
In this paper, we derive the random coding error exponent of amplify-and-forward (AF) relay networks in presence of arbitrary number of independent and identically distributed (i.i.d.) interferers both at the relay and the destination. Multiuser networks are common examples of interference limited networks. We derive the ergodic capacity of the network and present simulation results on the performance...
Asymmetric Distributed Source-Channel coding (DSC) is considered, where a pair of correlated sources are transmitting to a central node. The distributed scheme is based on Turbo Trellis Coded Modulation (TTCM), where the first source will be channel encoded and then compressed before it is sent over Nakagami-m fading channels. The second source signal, however, is assumed to be available flawlessly...
We consider the joint source-channel coding (JSCC) problem where the real valued outputs of two correlated memoryless Gaussian sources are scalar quantized, bit assigned, and transmitted, without applying any error correcting code, over a multiple access channel (MAC) which consists of two orthogonal point-to- point time-correlated Rayleigh fading sub-channels with soft- decision demodulation. At...
In this paper, we consider a fading relay channel where the source uses two layers source coding with successive refinement. The two source layers are transmitted using superposition coding at the source and relay with optimal power allocation, and successive interference cancellation at the receivers (i.e. relay and destination). The power allocation for the two layers at the source and relay is...
This paper presents an accurate approximation of the frame error rate (FER) of coded wireless communication systems with receiver diversity, such as single-input multiple-output (SIMO) systems with maximum ratio combining (MRC) or hybrid automatic repeat request (HARQ) systems with Chase combining. The signals at different diversity branches experience independent but non-identically distributed Rayleigh...
This paper studies the performance of adaptive modulation and coding in a cognitive incremental decode-and-forward relaying network where a secondary source can directly communicate with a secondary destination or via an intermediate relay. To maximize transmission efficiency, a policy which flexibly switches between the relaying and direct transmission is proposed. In particular, the transmission,...
We propose a method for estimating the average packet error rates (PER) of a coded orthogonal frequency division multiplexed (OFDM) system when the signal is subject to interference with a shaped spectral density. Thus the interference has a different impact on each sub-carrier. Typically, the PER is a function of the received signal-to-noise-ratio (SNR) and the packet bits are distributed evenly...
In this paper, we investigate the error exponents of dual-hop amplify-and-forward (AF) system for η-μ fading channel. Channel capacity of a wireless communication system gives only the knowledge of maximum achievable rate. Therefore, it is necessary to analyse the decoding complexity of the code that achieves a certain level of reliable communication. In fact, a measure of reliability called error...
Error correcting coding is a well-known technique for reducing the required signal-to-noise ratio (SNR) needed to attain a given bit error-rate. Nevertheless, this reduction comes at the cost of extra energy consumption introduced by the baseband processing required for encoding and decoding the data. No complete analysis of the trade-off between coding gain and baseband consumption of communications...
Radio Frequency Identification (RFID) is mostly used in harsh environments were deep fades occur. Taking into account a small scale fading channel and the UHF RFID transmission specified by the the EPCglobal protocol a poor communication performance is observed. As the decoding process of the received information is not specified in this protocol, there is a significant potential of increasing the...
Amplify and forward is a classical basic user cooperation scheme. In this paper, we propose a Physical-network-coding-based amplify and forward scheme. In time slot 2, users transmit the combinations of the partner's message and their own message through pseudo physical-layer network coding. This is the greater different from the classical scheme, where the user only transmits the partner's bits in...
We study a cooperation model where the positions of base stations follow a Poisson point process distribution and where Voronoi cells define the planar areas associated with them. For the service of each user, either one or two base stations are involved. If two, these cooperate by exchange of user data and reduced channel information (channel phase, second neighbour interference) with conferencing...
Cooperative communication is a new communication paradigm which generates independent paths between the user and the source by introducing a relay channel. The combination of bit-interleave coded modulation with Space-Time Coding (BI-ST) can provides space and time diversity simultaneously. This paper proposes a novel BI-ST wireless communication scheme (BI-ST-DF) for decode-and-forward (DF) cooperative...
This paper presents a novel algorithm to design Root-LDPC codes based on improved PEG algorithm for block fading channels. The modified Progressive Edge-Growth (MPEG) algorithm is a PEG algorithm with Approximated Cycle Extrinsic Message Degree (ACE) metric, which is used to describe the connectivity of cycles. The approach can maximize the girth of the cycles, improve the connectivity of cycles....
This paper proposes a novel deterministic inter-leaver, called almost linear interleaver (ALI) as the generalization of block and linear interleavers, and discusses its parameter/depth selection for coded orthogonal frequency division multiplexing (COFDM) system over Rayleigh fading channel. The concept of diversity guard is introduced to guarantee the achievable maximum diversity order with a reasonable...
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