Abstract – A novel hybrid multiuser detection scheme that jointly uses linear and nonlinear interference suppression techniques is developed for high-speed direct-sequence code-division multiple-access (DS/CDMA) communications in multipath frequency-selective fading channels. The detector detects signals in a symbol-by-symbol style. Conventional decorrelating detectors suffer from the noise enh...

Noise removal techniques play a vital role in the performance of electrocardiographic (ECG) signal processing systems. ECG signals can be corrupted by various kinds of noise such as baseline wander noise, electromyographic interference, and powerline interference. One of the significant challenges in ECG signal processing is the degradation caused by additive 50 or 60 Hz powerline interference....

We consider interference suppression for direct-sequence spread-spectrum code-division multiple-access (CDMA) systems using the minimum mean squared error (MMSE) performance criterion. The conventional matched filter receiver suffers from the near-far problem, and requires strict power control (typically involving feedback from receiver to transmitter) for acceptable performance. Multiuser dete...

The Fractional Fourier Transform (FrFT) performs better interference suppression than the fast Fourier Transform (FFT) when the signal-of-interest (SOI) or interference is nonstationary. Minimum mean-square error (MMSE) based filtering in the FrFT domain provides additional benefit in interference suppression in non-stationary environments. However, MMSE filtering requires computational covaria...

In this paper, an adaptive co-channel interference suppression technique for multi-user MIMO MC DS/CDMA system is envisaged. MC DS/CDMA offers many advantages like flexibility, robustness, low PAPR and spectral efficiency. In spite of these advantages, performance of MC DS/CDMA system is greatly impaired by interference. Common interferences, which degrade the performance of the system, are MAI...

This paper proposes a hybrid multiband (MB) ultra wideband (UWB) system with direct sequence (DS) spreading. The theoretical error analysis for the DS-MB-UWB multiple access system with Rake receiver in the presence of multipath and narrowband interference is developed. The developed theoretical framework models the multiple access interference (MAI), multipath interference (MI) and narrowband ...

The phenomenon of the polarization suppression of X-ray Umweg multiple waves in Renninger scans [Renninger (1937). Z. Kristallogr. 97, 107-121] of crystals, showing intensity decrease due to properly chosen wavelength and polarization of incident radiation, is observed. That is, one of the participating wave components in the multiple-wave interference is reduced considerably so that the intens...

GPS signals are very susceptible to interference due to weak satellite signal power. Multiple antenna receivers have been considered to be effective tools for interference suppression in GPS. In open loop nulling and localization schemes, we proceed with accurate interference directionof-arrival (DOA) estimates which enable a follow-on effective interference suppression using available spatial ...

RNAi (RNA interference) refers to the suppression of expression of a target gene (mainly at the post-transcriptional or translational level) induced by small (21-23 nucleotides) RNA molecules, including siRNA (small interfering RNA). Suppression of gene expression by RNAi represents an important part of the regulation of gene expression. Interestingly, recent advancements in RNAi research suppo...

BACKGROUND A specific problem using the public access defibrillators (PADs) arises at the railway stations. Some countries as Germany, Austria, Switzerland, Norway and Sweden are using AC railroad net power-supply system with rated 16.7 Hz frequency modulated from 15.69 Hz to 17.36 Hz. The power supply frequency contaminates the electrocardiogram (ECG). It is difficult to be suppressed or elimi...