Independent Components Analysis nds a linear transformation to variables which are maximally statistically independent. We examine ICA from the point of view of maximising the likelihood of the data. We elucidate how scaling of the unmixing matrix permits a \static" nonlinearity to adapt to various marginal densities and we demonstrate a new algorithm that uses generalised exponentials function...

Multiuser demodulation algorithms for centralized receivers of asynchronous direct-sequence (DS) spread-spectrum code-division multiple-access (CDMA) systems in frequency-selective fading channels are studied. Both DS-CDMA systems with short (one symbol interval) and long (several symbol intervals) spreading sequences are considered. Linear multiuser receivers process ideally the complete recei...

In this paper, we propose and analyze a multiuser receiver using a decorrelating filter and Viterbi decoders for trellis-coded direct-sequence code-division multiple-access (DS/CDMA) systems with biorthogonal signal constellation in asynchronous channels. The biorthogonality is implemented by user signature waveforms and the decorrelating filter. The performance of the proposed system is invest...

Long-code wideband CDMA receivers are for computational reasons usually based on simple matched-filter techniques, and hence suffer from multiaccess interference. To mitigate this problem, we propose computationally efficient decorrelating RAKE and MMSE receivers for the uplink of long-code CDMA systems. The decorrelating matched filter eliminates multiaccess interference by code matrix inversi...

A new puke position modulation code division multiple access (PPM-CDMA) system is proposed for an indoor optical wireless channeL As a signature sequence for CDMA an optical orthogonal code (OOC) is used To reduce multiple access interference, two interference cancellation schemes are employed: decorrelating detection and successive interference cancellation (SIC). The bit error rate of the pro...

The design of single-user decorrelating receivers employing nite-precision sequences for despreading is considered. The problem is formulated as a non-linear bounded integer optimization problem which is shown to be NP-hard. A branch-and-bound algorithm for nding the best nite-precision decorrelating sequence is described. Numerical examples demonstrate that the loss in performance between the ...

The strength of PS SAR interferometry stays with the availability of point-like targets coherent over many years [2]. In a previous work [4] we have investigated the possibility of extending the analysis to targets showing less ideal scattering properties, through the introduction of a covariance matrix estimated from the radar images. However since it is applied to a late phase of the processi...