Robustness to noise and low-bit rate coding distortion is one of the main problems faced by automatic speech recognition (ASR) and speaker verification (SV) systems in real applications. Usually, ASR and SV models are trained with speech signals recorded in conditions that are different from testing environments. This mismatch between training and testing can lead to unacceptable error rates. N...

Signal quantization in the presence of independent, identically distributed, large amplitude threshold noise is examined. It has previously been shown that when all quantization thresholds are set to the same value, this situation exhibits a form of stochastic resonance known as suprathreshold stochastic resonance. This means the optimal quantizer performance occurs for a small input signal-to-...

Heme Groups, Albumin, ^-Thalassemia, Electron Spin Resonance Homozygous beta thalassemic sera show an electron spin resonance (ESR) signal at g ~ 6 which is not present in normal and heterozygous sera. The signal arises from high spin heme groups exhibiting a departure from tetragonal symmetry toward rhombic. Binding by a serum protein is very likely responsible for such a distortion. In contra...

Using a theoretical approach based on random processes, signal processing, and information theory, we study the performance of digital watermarks subjected to an attack consisting of linear shift-invariant "ltering and additive colored Gaussian noise. Watermarking is viewed as communication over a hostile channel, where the attack takes place. The attacker attempts to minimize the channel capac...

A well-known drawback of orthogonal frequency-division multiplexing (OFDM) is its signal with high peak-to-average power ratio (PAPR). Among a number PAPR reduction techniques, clipping and filtering (CAF) the simplest approach, which effectively reduces band-limited OFDM signals at cost increasing in-band distortion. In order to mitigate performance degradation caused by distortion, several it...

Many analog-to-digital converter applications require low distortion for a very wide dynamic range of signals. Unfortunately, the distortion caused by digitizing an analog signal increases as the signal amplitude decreases, and is especially severe when the signal amplitude is of the same order as the quantizing step. In digital audio applications, for example, low-level signals occur often, so...

This paper shows how intermodulation distortion, IMD, sweet spots can be used as a practically meaningful technology to design highly linear microwave power amplifiers. It starts by reviewing the physical origins of these points of large signal to nonlinear distortion ratio, distinguishing the ones uniquely determined by the active device’s quiescent point – small-signal IMD sweet spots – from ...

In this paper, we investigate methods to optimise the bias point of an LED benefit from increasing bandwidth at higher driving current while minimising resulting signal distortion. The approaches are based on allowing for some nonlinear distortion or reduce swing/signal-to-noise ratio benefiting currents. A framework is presented estimate attainable capacity under both conditions. We also exper...