Using New Hybrid Integrators to Design IIR Fractional-Order Integrators via Impulse Invariance Method

This paper presents a method for designing fullband and non-fullband IIR digital integrators with linear phase that has been used to approximate fractional-order integrators with IIR filters. Several numerical integration rules have been considered in this study, namely, Euler, Simpson, Schneider, bilinear, and F₀₁₂. The main idea in our design is based on interpolating the well-known integration rules (Euler, Bilinear and Simpson) proposed by Al-Alaoui combined with deterministic signal modeling techniques. Numerical examples are presented to illustrate the performance of the proposed integrators. It was found that the Euler–Simpson integrator gives better approximation accuracy than existing integrators.     

Design and measurements of a RF front-end for Bi-band simultaneous reception

In this paper, we explore spectrum field band simultaneous receivers, with a special emphasis on only one aspect of these systems – the radio front-end. We propose, to validate in the lab, a receiver scheme for the simultaneous down-conversion of two signals in different bands. Obviously, the dedicated scheme is intended for practical use in an integrated circuit. In this work, the chosen receiver is implemented with discrete components. A test set is evaluated and compared to simulations; it contains mostly standard lab equipment, processing signals, according to the receiver scheme; this receiver presents merits and it is worth demonstrating in an integrated circuit.In order to give credit to the use of this type of receiver, the EDA model and results have to be validated by measurement. Therefore, based on the receiver architecture dedicated to an 802.11/UMTS simultaneous dual-channel processing, we design and fabricate a prototype. Firstly, we measure the intrinsic metrics of this prototype in terms of noise figure, gain, linearity, phase and gain mismatch between the two branches of the quadrature mounted mixers. In the present work, we demonstrate that, for instance, as NF and IIP3 change with the RF front-end gain with the improvement of the RF front-end performance, the linearity and the noise requirements are well handled. Afterwards, these metrics are injected in the EDA receiver model and simulations are done in order to evaluate the BER evolution.     

Protein sequence comparison based on the wavelet transform approach

A protein's chemical properties, the chain conformation, thefunction of the protein and its species specificity are determinedby the information contained in the amino acid sequence. Proteinsof similar functions have at some level sequential identicalamino acid sequences. The closer the phylogenetic relationship,the more similar are the sequences. To find the similaritiesbetween two or more protein sequences is of great importancefor protein sequence analysis. The differences in the aminoacid sequences permit the construction of a family tree of evolution.In this work, a comparison method was devised that is capableof analysing a protein sequence `hierarchically', i.e. it canexamine a protein sequence at different spatial resolutions.Based on a wavelet decomposition of protein sequences and across-correlation study, a sequence–scale similarity conceptis proposed for generating a similarity vector, which rendersthe comparison of two sequences feasible at different spatialresolutions (scales). This new similarity concept is an expansionof the conventional sequence similarity, which only takes intoaccount the local pairwise amino acid match and ignores theinformation contained in coarser spatial resolutions.