In recent years, there has been considerable interest in the use of CDMA in mobile communications. Bit error rate is one of the most important parameters in the evaluation of CDMA systems. In this paper, we develop a technique to find an accurate approximation to the probability of bit error for asynchronous direct–sequence code division multiple–access (DS/CDMA) systems by modeling the multipl...

We consider a game-theoretic power control algorithm for wireless data realistic channels. We study the performance of the algorithm for wireless data in the fast, flat-fading channel mobile users encounter in accessing the cellular system. The game-theoretic power control algorithm depends on an average utility function that assigns a numerical value to the quality of service (QoS) of users. T...

One channel model that characterises multipath fading efiFect of a wireless channel is called Flat Rayleigh Fading channel model. Given the properties of Flat Rayleigh Fading channel, an equation to find the capacity of a Flat Rayleigh fading channel with hard decision decoding is derived. The difference of power requirement to achieve the Additive White Gaussian Noise (AWGN) capacity over a Fl...

Diversity combining techniques play an important role in combating the destructive effects of channel fading in wireless communication systems. In this work we present a blind diversity combining technique for Rayleigh flat fading channels based on Hammerstein type filters. We show that the performance of this technique is very close to ideal MRC system which is accepted as an optimum receiver ...

Abstract— This paper addresses the design and performance evaluation with respect to capacity of M-PSK turbo-coded systems operating in frequency-flat, time-selective Rayleigh fading. The receiver jointly performs channel estimation and turbo decoding, allowing the two processes to benefit from each other. To this end, we introduce a suitable Markov model with a finite number of states, designe...

This paper represents the MIMO channel capacity over Rician fading, Rayleigh fading and Nakagami fading channel. Here Rician fading model employs a zero-mean stochastic sinusoid as the line-of-sight component. This paper offers analyses and simulations to the behavior of MIMO system and its expected capacity for various channel distribution under flat fading. Several types of distributions (Ric...

The ergodic capacity, capacity distribution and outage capacity are investigated for MIMO wireless systems under time-varying and frequency-selective Rayleigh fading channels. Our theoretical results and Monte-Carlo simulations show that: (1) if the frequency-selective Rayleigh fading channel impulse response has no inter-tap correlations, then its ergodic capacity is the same as that of the fr...

In this paper the trade-off between time diversity and the inter-carrier interference (ICI) in an OFDM based MC-CDMA system is discussed. Our approach is to partially shift each spectrum of an OFDM symbol at the transmitter by using different phase shifts in the time domain at different antennas after the OFDM modulation. The summary signal at the receiver has a wider Doppler spectrum as the re...

In this paper we examine the impact of channel fading on the bit error rate of a DS-CDMA communication system. The system employs detectors that incorporate neural networks effecting methods of independent component analysis (ICA), subspace estimation of channel noise, and Hopfield type neural networks. The Rayleigh fading channel model is used. When employed in a Rayleigh fading environment, t...

A numerical method has recently been presented to determine the noise thresholds of low density parity-check (LDPC) codes that employ the message passing decoding algorithm on the additive white Gaussian noise (AWGN) channel. In this paper, we extend this technique to the uncorrelated flat Rayleigh fading channel. Using a nonlinear code optimization technique, we optimized irregular LDPC codes ...