background and aim: as the most perceived and articulated errors of hearing aid users occur in high frequency speech phonemes, this study aimed to find a way to amplify and reconstruct the errors. thus, the study first prepared a recorded form of two persian fricative consonants as stimulus; then, the rate of the prescribed gain of the two methods of national acoustic laboratories-nonlinear 2 (...

Frequency hopping (FH) sequences play a key role in frequency hopping spread spectrum communication systems. It is important to find FH sequences which have simultaneously good Hamming correlation,large family size and large period. In this paper, a new set of FH sequences with large period is proposed, and the Hamming correlation distribution of the new set is investigated. The construction of...

We propose a new approach to broadband Stimulated Raman Scattering (SRS) spectroscopy and microscopy based on time-domain Fourier transform (FT) detection of the stimulated Raman gain (SRG) spectrum. We generate two phase-locked replicas of the Stokes pulse after the sample using a passive birefringent interferometer and measure by the FT technique both the Stokes and the SRG spectra. Our appro...

Abstract This paper proposes a fractional-order reset element whose architecture allows for the suppression of nonlinear effects range frequencies. Suppressing desired frequency while maintaining it rest is beneficial, especially when used in framework “Constant gain, Lead phase” (CgLp) filter. CgLp newly introduced filter, bound to circumvent well-known linear control limitation—the waterbed e...

For frequencies >10 Hz, the vestibuloocular reflex (VOR) has been primarily investigated during passive rotations of the head on the body in humans. These prior studies suggest that eye movements lag head movements, as predicted by a 7-ms delay in the VOR reflex pathways. However, Minor and colleagues recently applied whole-body rotations of frequencies < or =15 Hz in monkeys and found that eye...

Frequency hopping spread spectrum and direct sequence spread spectrum are two main spread coding technologies. Frequency hopping sequences are needed in FH-CDMA systems. In this paper, a construction of optimal sets of frequency hopping sequences is presented via cyclotomy. The construction is based on the set-theoretic characterization of an optimal set of FH sequences. As a consequence, new o...

Design and simulation of 7 GHz CMOS wideband amplifier(CMOSWA) using a modified cascode circuit realized in 90-nm technology is presented here. The proposed system consists two stages, namely folded an inductively degenerated common source amplifier. experimented with without feedback network. This work discusses the performance variation as function reactive components, initial stage results 2...

High-quality GaAs/AlGaAs quantum well and modulation-doped heterostructures have been grown by low-pressure organometallic vapor phase epitaxy (OMVPE) using trimethylamine alane (TMAA) as a new aluminum source. TMAA is an alternative to the conventional organometallic precursors and offers the advantage of substantially reduced oxygen and carbon incorporation in AlGaAs. Intense photoluminescenc...

Active filters play important role in communication systems. They can be obtained and constructed by different methods. Recently, there is a tendency of designing current-mode circuits using unity-gain active elements such as, CFOAs, CCIIs, etc. instead of classical infinite gain operational amplifiers in active filter design. This paper presents transresistance multifunction filter realization...

AlGaN/GaN high-electron-mobility transistors (HEMT) have been grown by radio frequency molecular beam epitaxy (RF-MBE) on 3” Si substrates. A record low contact resistance Rc ~ 0.11 .mm has been achieved for GaN HEMTs on Si by using non alloyed ohmic contacts regrown by MBE. Owing to the low contact resistance a 75-nm gate length unpassivated HEMT shows intrinsic current gain cut-off frequency ...