In this paper we present a summary of nonlinear system level problems in beamforming. The paper summarizes first the nonideal phenomena in power amplifiers, mixers, and oscillators. In digital predistortion inversion of the nonlinearity is needed. Not all linear and nonlinear systems are invertible or they may have only a preinverse or postinverse. Commutation is needed in indirect learning arc...

duffing harmonic oscillator is a common model for nonlinear phenomena in science and engineering. this paper presents he´s energy balance method (ebm) for solving nonlinear differential equations. two strong nonlinear cases have been studied analytically. analytical results of the ebm are compared with the solutions obtained by using he´s frequency amplitude formulation (faf) and numerical solu...

A fundamental electrokinetic phenomenon is the electro-osmotic flow of a liquid electrolyte (solution of positive and negative ions) past a charged surface in response to a tangential electric field. Electrophoresis is the related phenomenon of motion of a colloidal particle or molecule in a background electric field, propelled by electro-osmotic flow in the opposite direction. The basic physic...

Duffing harmonic oscillator is a common model for nonlinear phenomena in science and engineering. This paper presents He´s Energy Balance Method (EBM) for solving nonlinear differential equations. Two strong nonlinear cases have been studied analytically. Analytical results of the EBM are compared with the solutions obtained by using He´s Frequency Amplitude Formulation (FAF) and numerical solu...

in this study, nonlocal nonlinear instability and the vibration of a double carbon nanotube (cnt) system have been investigated. the visco-pasternak model is used to simulate the elastic medium between nanotubes, on which the effect of the spring, shear and damping of the elastic medium is considered. both of the cnts convey a viscose fluid and a uniform longitudinal magnetic field is applied t...