In this paper we study differential detection of binary differential phase shift keyed (DPSK) signals with several impairments typical in satellite communication systems. In pariicjlar; the bit error rate is determined for bit timing error and frequency offset error at the receiver. The effect of a hard-limiting, band-limited repeater is also considered. The differential detector performance is...

A lot of improvements were introduced lately in order to increase the verification performance of biometric user authentication systems. One method, besides many others, is the selection of specific features for each user during the verification process. In this paper we present a security analysis of a user specific bit mask vector, which was originally introduced to improve verification perfo...

A class of formulas for the numerical evaluation of multiple integrals is described, which combines features of the Monte-Carlo and the classical methods. For certain classes of functions—defined by smoothness conditions—these formulas provide the fastest possible rate of convergence to the integral. Asymptotic error estimates are derived, and a method is described for obtaining good a posterio...

The main purpose of this paper is to show that once the video source coding is dependent on the channel characteristics, better performance can be achieved in terms of reconstructed video quality. Our study considers a fixed overall bit rate transmission of 64 kbit/s over error prone memoryless binary channels and the source coder is the ITU-T H.263 video standard. The variable H.263 source cod...

In Handwritten signatures analyzed for forgery have to undergo feature extraction process, due to varied samples in size rotation and intra-domain changes, invariance has to be achieved during feature extraction process; circular Hidden Markov Model with discrete radon transform approach of feature extraction provides invariance. On other hand Scale Invariant Feature Transform (SIFT) has inhere...

Generally speaking, spoken term detection system will degrade significantly because of mismatch between acoustic model and spontaneous speech. This paper presents an improved spoken term detection strategy, which integrated with a novel phoneme confusion matrix and an improved word-level minimum classification error MCE training method. The first technique is presented to improve spoken term de...

In this paper, we compare the performance of using binaural audio features in place of single channel features for sound event detection. Three different binaural features are studied and evaluated on the publicly available TUT Sound Events 2017 dataset of length 70 minutes. Sound event detection is performed separately with single channel and binaural features using stacked convolutional and r...

Conventional Boosting algorithms for acoustic modeling have two notable weaknesses. (1) The objective function aims to minimize utterance error rate, though the goal for most speech recognition systems is to reduce word error rate. (2) During Boosting training, an utterance is treated as a unit for resampling and each frame within the same utterance is assigned equal weight. Intuitively, the fr...

The Enhanced Variable Rate Codec (EVRC) is a standard for the “Speech Service Option 3 for Wideband Spread Spectrum Digital System,” which has been employed in both IS-95 cellular systems and ANSI J-STC-008 PCS (Personal Communications Systems). This paper investigates the combination of turbo codes with Unequal Error Protection (UEP) and 16-QAM modulation for EVRC codec of Rate 1 to get power ...

The subject of this paper is robust voice activity detection (VAD) in noisy environments, especially in car environments. We present a comparison between several frame based VAD feature extraction algorithms in combination with different classifiers. Experiments are carried out under equal test conditions using clean speech, clean speech with added car noise and speech recorded in car environme...