We use the cutoff rate to analyze reliable rates over the firstorder Guass-Markov fading channel when an optimized pilot-symbol assisted modulation (PSAM) scheme is used to provide partial CSI to the receiver. The transmitter uses BPSK modulation, and has knowledge of the SNR at the receiver and the normalized doppler spread only. Under an average energy constraint, closed form expressions are ...

The performance of burst-by-burst adaptive modulation is studied in conjunction with reduced complexity turbo equalization over a wideband multi-path Rayleigh fading channel. By employing the reduced complexity turbo equalizer, higher-order modulation modes such as 64-level Quadrature Amplitude Modulation (64-QAM) can be invoked, than upon using the conventional turbo equalizer. The structure o...

Opportunistic spectrum access is based on channel state information and can lead to important performance improvements for the underlying communication systems. On the other hand adaptive modulation is also based on channel state information and can achieve increased transmission rates in fading channels. In this work we propose the combination of adaptive modulation with opportunistic spectrum...

Different order modulations combined with different coding schemes, allow sending more bits per symbol, thus achieving higher throughputs and better spectral efficiencies. However, it must also be noted that when using a modulation technique such as 64-QAM with less overhead bits, better signal-to-noise ratios (SNRs) are needed to overcome any Intersymbol Interference (ISI) and maintain a certa...

This paper provides guidelines for Wireless ATM (WATM) link dimensioning and coding parameters optimisation subject to meeting specified Quality of Service (QoS) requirements. It takes into consideration a comprehensive set of coding as well as teletraffic issues: (1) effects of retransmissions of erroneous packets using Automatic Repeat Request (ARQ) protocols, (2) modulation efficiency (3) Fo...

Department of Electrical Power and Machines Faculty of Engineering Cairo University Giza, Egypt Abstract The quality of the current waveform generated by a current controlled, voltage source shunt active power filter depends basically on three factors: (i) The reference signal being generated; (ii) the modulation method used and (iii) the switching frequency of the PWM modulator. A new adaptiv...

In this paper, we employ normalized modulation spectral analysis for voice pathology detection. Such normalization is important when there is a mismatch between training and testing conditions, or in other words, employing the detection system in real (testing) conditions. Modulation spectra usually produce a high-dimensionality space. For classification purposes, the size of the original space...

We investigate the impact of self-interference on the performance of joint partial RAKE (PRAKE) receiver and adaptive modulation over both independent and identically distributed and independent but non-identically distributed Rayleigh fading channels in the presence of self-interference in terms of the average spectral efficiency as performance measures. Some selected results show the performa...

In this paper, an adaptive relay scheme based on post SNR in cooperative communication system is proposed. conventional cooperative scheme has used the same modulation at a relay. The proposed scheme uses hierarchical modulation at the source and adaptive transmission based on the post signal to noise ratio (SNR) at a relay. Accordingly, the symbol error rate (SER) and throughput performances a...

In this paper, we consider the problem of embedded image transmission with feedback of channel state information (CSI) and retransmission request. Adaptive modulation is employed to improve the spectral efficiency. Constrained retransmission is employed to provide reliable packet transmission with limited delay. Performance analysis and numerical results over Nakagami blockfading channels are p...