We report a multi–dimensional quadrature amplitude modulation with M-ary differential phase shift keying (QAM-MDPSK) for optical access network transmission systems employing Mach–Zehnder modulator (MZM) and (PM) in direct detection system. Even though several problems that occur QAM-DPSK single MZM were solved, inter-signal distortion between two modulations remains when the signal is converte...

In this paper we apply the Weighted Acoustic Modeling (WAM) technique to the recognition of speech coded by the full-rate GSM codec or the FS-1016 CELP codec employing various estimates of instantaneous distortion. In the WAM method, separate hidden Markov models are developed for regions of speech that exhibit low levels of codec-induced distortion and for regions with higher levels of such di...

With the improvement of synthetic aperture radar (SAR) technology, larger areas are being imaged and the resolution of the images has increased. Larger images have to be transmitted and stored. Due to the limited storage and/or downlink capacity on the airplane or satellite, the volume of the data must be reduced. This makes compression of SAR images with minimal loss of information important. ...

A new intelligibility prediction measure, called “Gammachirp Envelope Distortion Index (GEDI)” is proposed for the evaluation of speech enhancement algorithms. This model calculates the signal-to-distortion ratio (SDR) in envelope responses SDRenv derived from the gammachirp filterbank outputs of clean and enhanced speech, and is an extension of the speech based envelope power spectrum model (s...

Data hiding using quantization has revealed as an effective way of taking into account side information at the encoder. When quantizing more than one host signal samples there are two choices: 1) using the Cartesian product of several one-dimensional quantizers, as made in Scalar Costa Scheme (SCS); or 2) performing vectorial quantization. The second option seems better, as rate-distortion theo...

This paper aims to develop a generalized framework to systematically trade off computational complexity with output distortion in linear transforms such as the DCT, in an optimal manner. The problem is important in real-time systems where the computational resources available are time-dependent. Our approach is generic and applies to any linear transform and we use the DCT as a specific example...

In this paper, we present the analysis of the multicarrier transmission based on peak-to-average power ratio reduction techniques based on Signal distortion technique. Multiplexing a serial data symbol stream into a large number of orthogonal sub-channels makes the multicarrier signals spectral bandwidth efficient. The performance of multicarrier modulation system over frequency selective fadin...