In this paper, a two-dimensional multi-wavelet is constructed in terms of Chebyshev polynomials. The constructed multi-wavelet is an orthonormal basis for space. By discretizing two-dimensional Fredholm integral equation reduce to a algebraic system. The obtained system is solved by the Galerkin method in the subspace of by using two-dimensional multi-wavelet bases. Because the bases of subs...

In this review article, a stage-convertible RF power amplifier designed with a 0.18-m RF CMOS process is described. A method to implement a low-power matching network is an essential technology for the stage-convertible power amplifier. Various low-power matching networks with distributed active transformers as an output power combiner are compared in terms of the amounts of undesired coupling...

Recent theoretical work predicts that the quantum-limited noise figure of a x(3)-based fiber-optical parametric amplifier operating as a phase-insensitive in-line amplifier or as a wavelength converter exceeds the standard 3-dB limit at high gain. The degradation of the noise figure is caused by the excess noise added by the unavoidable Raman gain and loss occurring at the signal and the conver...

In this paper, we investigate the parameters affecting Total Harmonic Distortion (THD) and Power Supply Rejection Ratio (PSRR) in PWM Class D Amplifiers (CDAs) on the basis of linear models with feedback. From our mathematical analysis, we show that the THD of a PWM Class D amplifier with feedback can be improved by increasing the gain of the integrator through adding another amplifier at the o...

A power amplifier (PA) is a key part of the RF front-end in transmitters for a local broadband network. Today, commercial PAs are made of III-V HEMT and HBT technology with excellent results. An integrated system-on-chip power amplifier circuit using CMOS technology for cost-effective and spectrum-efficient high-speed wireless communication presents major challenges because power amplifiers hav...

Photograph of a mechanically flexible 2D-DFB laser made from the conjugated polymer MeLPPP. The laser is optically pumped well above the threshold for amplified spontaneous emission. The complex far-field emission pattern (blue-green) results from a large detuning between the resonance wavelength and the gain maximum. • A nearly diffraction limited surface emitting conjugated polymer laser util...

We present the design of Analog front end (AFE) low noise pre-amplifier implemented in a high voltage 0.18-μm CMOS technology for a three dimensional ultrasound bio microscope (3D UBM) application. The fabricated chip has 4X16 pre-amplifiers implemented to interface a 2-D array of high frequency capacitive micro-machined ultrasound transducers (CMUT). Core AFE cell consists of a high-voltage pu...

The two-dimensional Navier-Stokes equations are rewritten as a system of coupled nonlinear ordinary differential equations. These equations describe the evolution of the moments of an expansion of the vorticity with respect to Hermite functions and of the centers of vorticity concentrations. We prove the convergence of this expansion and show that in the zero viscosity and zero core size limit ...

This paper presents a predictable fixed gain instrumentation amplifier using switched capacitor instead of resistor to improve the accuracy of the gain as 10. This instrumentation amplifier builds up by two operational amplifiers which connect by switched capacitor. These switched capacitors are used to stable the whole circuit, fix the gain of total instrumentation amplifier. Using two operati...