In this paper, an equalization technique for OFDM and MC-CDMA systems in a time-varying multipath fading environment is described. A loss of subchannel orthogonality due to time-variation of multipath channels leads to interchannel interference (ICI) which increases the error oor in proportion to Doppler frequency. A simple frequency domain equalizer which can compensate the e ect of time-varia...

This paper represents an end-to-end baseband model of the physical layer of a WiMAX network according to the IEEE® 802.16 standard. The model supports all mandatory and optional data rates 27 Mb/s. The model also illustrates adaptive modulation and coding over a flat-fading and dispersive multipath fading channel, whereby the simulation varies the data rate dynamically The channel estimation te...

A continuous adaptive modulation multitone system for multipath fading channels is shown. To obtain a target BER and maximum aggregated rate, each subcarrier bit rate is modified independently to adjust the transmitted signal to the spectral channel shape and to track the channel variations dynamically. Spectral efficiency and the required feedback channel capacity are obtained through simulati...

An adaptive multipath decorrelating multiuser receiver is considered for application in Rayleigh fading multipath channels with significant Doppler spread. Coherent diversity combining is performed using adaptively obtained channel estimates in a manner that minimizes the impact of estimation errors on data detection. The bit-error rate of the receiver is evaluated analytically, showing depende...

The constrained MMSE (CMMSE) receiver, which has been developed for flat fading channels [6], is applied to each finger of a RAKE receiver in multipath fading environment. The optimal filter coefficients of the CMMSE receiver in steady state are derived. The results indicate that the performance of CMMSE receivers can be degraded by interpath interference (IPI) when the channel fade rate is slo...

In recent years chaotic secure communication and chaos synchronization have received ever increasing attention. Unfortunately, despite the advantages of chaotic systems, Such as, noise-like correlation, easy hardware implementation, multitude of chaotic modes, flexible control of their dynamics, chaotic self-synchronization phenomena and potential communication confidence due to the very dynami...

In this paper, we propose a multiuser detection (MUD) scheme for space-time block coded orthogonal frequency division multiplexing (STBC-OFDM) systems. We derive the optimum weight matrix used to decouple simultaneously signals from active multiple access users using the minimum mean square error (MMSE) multiuser detection method. The proposed scheme provides good performance over different mod...

An analytical model is developed for the performance of a microcellular radio network in the presence of co-channel interference and additive white Gaussian noise. The modulation schemes considered are BPSK, BFSK, and QPSK. The multiple-access channel is statistically modeled by one Rician-distributed desired signal and several uncorrelated Rayleigh plus log-normally shadowed interfering signal...

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Zhong Zheng Name of the doctoral dissertation Statistical Analysis of Cascaded Multipath Fading Channels Publisher School of Electrical Engineering Unit Department of Communications and Networking Series Aalto University publication series DOCTORAL DISSERTATIONS 209/2015 Field of research Communications Engineering Manuscript ...