In this paper we propose a blind interference cancellation (IC) receiver for asynchronous direct-sequence code-division multiple-access (DSCDMA) systems using a maximum mean energy (MME) optimization criterion. The simulation results show that this scheme offers performance gains over the well known blind receiver that is based on the minimum mean squared error (MMSE) optimization criterion. Ou...

A new method for frequency synchronization based upon Zero-Intermediate Frequency (Zero-IF) receiver and characteristics of the received signal’s power spectrum for MC-DSCDMA-Uplink system is proposed in this paper. In addition to this, employing Zero Correlation Zone (ZCZ) sequences, designed specifically for quasisynchronous uplink transmissions, is proposed to exploit frequency and temporal ...

The problem of estimating propagation delays of orthogonally modulated signals in asynchronous DSCDMA system over time-varing Rayleigh-fading channels is treated in this paper. The Maximum Likelihood (ML) estimator and its unaffordable complexity for implementation are discussed. Some suboptimal solutions, e.g., whitened sliding correlator, MMSE estimator, subspace-based estimator, approximate ...

Orthogonal and quasi-orthogonal codes are integral part of any DSCDMA based cellular systems. Orthogonal codes are ideal for use in perfectly synchronous scenario like downlink cellular communication. Quasi-orthogonal codes are preferred over orthogonal codes in the uplink communication where perfect synchronization cannot be achieved. In this paper, we attempt to compare orthogonal and quasi-o...

One of the promising techniques to allow highspeed data transmission with a limited bandwidth is multiinput multi-output (MIMO) multiplexing. As a signal separation scheme, an iterative frequency-domain interference cancellation (FD-IC) using two-dimensional minimum mean square error (2D-MMSE) frequencydomain equalization (FDE) was recently proposed. There are two types of FD-IC: parallel FD-IC...

| Against the back-cloth of the explosive expansion of the Internet and the continued dramatic increase in demand for high-speed multimedia wireless services, there is an urging demand for exible, broadband transceivers. A versatile broadband multiple access scheme, combining frequency-hopping (FH) with multicarrier DSCDMA (FH/MC DS-CDMA) is proposed and investigated. The FH/MC DS-CDMA scheme i...

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