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On the Minimum Differential Feedback for Time-Correlated MIMO Rayleigh Block-Fading Channels  [PDF]
L. Zhang,Lingyang Song,M. Ma,B. Jiao
Mathematics , 2011,
Abstract: In this paper, we consider a general multiple input multiple output (MIMO) system with channel state information (CSI) feedback over time-correlated Rayleigh block-fading channels. Specifically, we first derive the closed-form expression of the minimum differential feedback rate to achieve the maximum erdodic capacity in the presence of channel estimation errors and quantization distortion at the receiver. With the feedback-channel transmission rate constraint, in the periodic feedback system, we further investigate the relationship of the ergodic capacity and the differential feedback interval, and we find by theoretical analysis that there exists an optimal differential feedback interval to maximize ergodic capacity. Finally, analytical results are verified through simulations in a practical periodic differential feedback system using Lloyd's quantization algorithm.
Probability of Error of Linearly Modulated Signals with Gaussian Cochannel Interference in Maximally Correlated Rayleigh Fading Channels  [cached]
Rugini Luca,Banelli Paolo
EURASIP Journal on Wireless Communications and Networking , 2010,
Abstract: We evaluate the probability of error of linearly modulated signals, such as phase-shift keying (PSK) and quadrature amplitude modulation (QAM), in the presence of Gaussian cochannel interference (CCI) and Rayleigh fading channels. Specifically, we assume that the fading channel of the CCI is maximally correlated with the fading channel of the signal of interest (SOI). In practical applications, the maximal correlation of the CCI channel with the SOI channel occurs when the CCI is generated at the transmitter, such as the multiuser interference in downlink systems, or when a transparent repeater relays some thermal noise together with the SOI. We analytically evaluate the error probability by using a series expansion of generalized hypergeometric functions. A convenient truncation criterion is also discussed. The proposed theoretical approach favorably compares with alternative approaches, such as numerical integration and Monte Carlo estimation. Among the various applications of the proposed analysis, we illustrate the effect of nonlinear amplifiers in orthogonal frequency-division multiplexing (OFDM) systems, the downlink reception of code-division multiple-access (CDMA) signals, and the outdoor-to-indoor relaying of Global Positioning System (GPS) signals.
A Unified Approach to BER Analysis of Synchronous Downlink CDMA Systems with Random Signature Sequences in Fading Channels with Known Channel Phase  [cached]
M. Moinuddin,A. U. H. Sheikh,A. Zerguine,M. Deriche
EURASIP Journal on Advances in Signal Processing , 2008, DOI: 10.1155/2008/346465
Abstract: A detailed analysis of the multiple access interference (MAI) for synchronous downlink CDMA systems is carried out for BPSK signals with random signature sequences in Nakagami-m fading environment with known channel phase. This analysis presents a unified approach as Nakagami-m fading is a general fading distribution that includes the Rayleigh, the one-sided Gaussian, the Nakagami-q, and the Rice distributions as special cases. Consequently, new explicit closed-form expressions for the probability density function (pdf ) of MAI and MAI plus noise are derived for Nakagami-m, Rayleigh, one-sided Gaussian, Nakagami-q, and Rician fading. Moreover, optimum coherent reception using maximum likelihood (ML) criterion is investigated based on the derived statistics of MAI plus noise and expressions for probability of bit error are obtained for these fading environments. Furthermore, a standard Gaussian approximation (SGA) is also developed for these fading environments to compare the performance of optimum receivers. Finally, extensive simulation work is carried out and shows that the theoretical predictions are very well substantiated.
Lattice Code Design for the Rayleigh Fading Wiretap Channel  [PDF]
Jean-Claude Belfiore,Frederique Oggier
Mathematics , 2010,
Abstract: It has been shown recently that coding for the Gaussian Wiretap Channel can be done with nested lattices. A fine lattice intended to the legitimate user must be designed as a usual lattice code for the Gaussian Channel, while a coarse lattice is added to introduce confusion at the eavesdropper, whose theta series must be minimized. We present a design criterion for both the fine and coarse lattice to obtain wiretap lattice codes for the Rayleigh fading Wiretap Channel.
Interference rejection in DS-CDMA multiuser systems based on fash optimization of the despreading filter
基于快速解扩滤波器优化的DS-CDMA多用户干扰抑制

Li Pingan,Hu Bing,Zhang Hong,Yang Xiaopeng,
李平安
,胡兵,章红,杨霄鹏

电子与信息学报 , 2002,
Abstract: In this paper, a new technique for DS-CDMA signal detection is proposed. By using the orthogonally-anchored generalized sidelobe canceller structure and training sequence, last/uonadaptive optimization is achieved based on the minimum-output-energy criterion. The output signal to interference plus noise ratio of the code matched filter is effectively applied to suppress the effect of mismatch on optimization of the despreading filter, which results in robust multi-user access interference cancellation. Furthermore, the RAKE combining technique is used to improve the performance of the receiver in Rayleigh fading channels.
An Implementation of Nonlinear Multiuser Detection in Rayleigh Fading Channel
Wai Yie Leong,John Homer,Danilo P. Mandic
EURASIP Journal on Wireless Communications and Networking , 2006,
Abstract: A blind nonlinear interference cancellation receiver for code-division multiple-access- (CDMA-) based communication systems operating over Rayleigh flat-fading channels is proposed. The receiver which assumes knowledge of the signature waveforms of all the users is implemented in an asynchronous CDMA environment. Unlike the conventional MMSE receiver, the proposed blind ICA multiuser detector is shown to be robust without training sequences and with only knowledge of the signature waveforms. It has achieved nearly the same performance of the conventional training-based MMSE receiver. Several comparisons and experiments are performed based on examining BER performance in AWGN and Rayleigh fading in order to verify the validity of the proposed blind ICA multiuser detector.
An Implementation of Nonlinear Multiuser Detection in Rayleigh Fading Channel  [cached]
Leong WaiYie,Homer John,Mandic Danilo P
EURASIP Journal on Wireless Communications and Networking , 2006,
Abstract: A blind nonlinear interference cancellation receiver for code-division multiple-access- (CDMA-) based communication systems operating over Rayleigh flat-fading channels is proposed. The receiver which assumes knowledge of the signature waveforms of all the users is implemented in an asynchronous CDMA environment. Unlike the conventional MMSE receiver, the proposed blind ICA multiuser detector is shown to be robust without training sequences and with only knowledge of the signature waveforms. It has achieved nearly the same performance of the conventional training-based MMSE receiver. Several comparisons and experiments are performed based on examining BER performance in AWGN and Rayleigh fading in order to verify the validity of the proposed blind ICA multiuser detector.
Stochastic Geometry-Based Performance Bounds for Non-Fading and Rayleigh Fading Ad Hoc Networks  [PDF]
Hieu Duy Nguyen,Sumei Sun
Mathematics , 2015,
Abstract: In this paper, we study the performance of non-fading and Rayleigh fading ad hoc networks. We first characterize the distribution of the signal-to-interference-plus-noise ratio (SINR) through the Laplace transform of the inverted SINR for non-fading channels. Since most communication systems are interference-limited, we also consider the case of negligible noise power, and derive the upper and lower bounds for the signal-to-interference ratio (SIR) distribution under both non-fading and fading cases. These bounds are of closed forms and thus more convenient for theoretical analysis. Based on these derivations, we obtain closed-form bounds for both the average Shannon and outage rates. We also leverage the above results to study partial fading ad-hoc systems. These results are useful for investigating and comparing fifth-generation communication systems, for example massive multi-antenna and small-cell networks as in our illustrative example.
Simulation Based Performance Analysis of MCCDMA and CDMA over Rayleigh Fading Channel  [PDF]
Mohammed Faisal,Jia Uddin,Iqbal Hasan Haider
International Journal on Internet and Distributed Computing Systems , 2012,
Abstract: Multicarrier Code Division Multiple Access Schemes (MC-CDMA) have been recently introduced in existing CDMA based systems to improve security, data transmission rate and to minimize Inter Symbol Interference (ISI). CDMA experiences severe multipath fading which badly affects its performance. By transmitting identical narrowband Direct- Sequence (DS) waveforms using frequency diversity, in parallel with a number of subchannels, multipath fading could be minimized. Implementation of this multicarrier modulation technique in CDMA system is known as multicarrier CDMA. We have shown that in Rayleigh Fading Channel, due to multicarrier modulation, when one subcarrier goes deep fade, another subcarrier remains safe. Therefore MC-CDMA can combat multipath fading better than CDMA and signal can be received in low bit error rate (BER).
Performance of Optimum Combining in a Poisson Field of Interferers and Rayleigh Fading Channels  [PDF]
Olfa Ben Sik Ali,Christian Cardinal,Francois Gagnon
Mathematics , 2010,
Abstract: This paper studies the performance of antenna array processing in distributed multiple access networks without power control. The interference is represented as a Poisson point process. Desired and interfering signals are subject to both path-loss fading (with an exponent greater than 2) and to independent Rayleigh fading. Using these assumptions, we derive the exact closed form expression for the cumulative distribution function of the output signal-to-interference-plus-noise ratio when optimum combining is applied. This results in a pertinent measure of the network performance in terms of the outage probability, which in turn provides insights into the network capacity gain that could be achieved with antenna array processing. We present and discuss examples of applications, as well as some numerical results.
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