​ *Corresponding author's address: Equipe Acoustique Instrumentale, IRCAM, 1 place Igor Stravinsky, Paris, 75004, Paris, France, [email protected] Active control is widely used in industry. However, there have been relatively few applications to musical instruments, particularly wind instruments. The aim of this study is to attempt to control the sound quality and playability of wind in...

This paper discusses the measurement of the acoustical properties of tubular systems using pulse reflectometry. The technique involves the injection of a sound pulse into the object under investigation and the recording of the resultant reflections. Analysis of the reflections gives information about the bore profile and input impedance of the object. The effect of small leaks on both of these ...

Frequency-swept input-impedance measurements to determine Q factors and field strengths for an electrically small tuned transmitting loop antenna in its operating environment have recently been made. These observational results are compared with numerical modeling by the computational electromagnetic code NEC-4D, since the validity of this code to simulate the performance of electrically small ...

Thévenin’s theorem is used to represent a part of a network by a voltage source Vt and a series impedance Zt , as shown in Fig. D.1. Figure D.1(a) shows a network divided into two parts, A and B. In Fig. D.1(b), part A of the network has been replaced by its Thévenin equivalent: a voltage source Vt and a series impedance Zt . Figure D.1(c) illustrates how Vt is to be determined: Simply open-cir...

A novel load pull methodology to characterize the performance of class-E outphasing power amplifiers is presented. The traditional analysis of the outphasing topology cannot be applied when classE amplifiers are used because these amplifiers do not behave as an ideal current or voltage source. Unlike most other amplifier classes, class-E amplifiers require a phase modulated input signal with co...

Maximum power transfer tracking (MPTT) is meant to track the maximum power point during the system operation of wireless power transfer (WPT) systems. Traditionally, MPTT is achieved by impedance matching at the secondary side when the load resistance is varied. However, due to a loosely coupling characteristic, the variation of coupling coefficient will certainly affect the performance of impe...

A full wave spectral domain method of moment along with reciprocity theorem analysis of finite phased array of aperture coupled circular microstrip patch antennas is presented. Both the electric surface currents on the patches and the equivalent magnetic current on the apertures are considered. Results of reflection coefficient magnitude, active input impedance, active element gain, efficiency ...

This study proposes a concurrent dual-band filter that consists of two single-band filters using quarter-wavelength resonators. The two single-band filters, having different feeding structures, can be designed separately. The lower-band filter has tapped feeding structure and the higher-band filter has coupling feeding structure where the input/output line and the lower-band resonator constitut...

The CARIOCA front-end is an amplifier discriminator chip, using 0.25Pm CMOS technology, developed with a very fast and low noise preamplifier. This prototype was designed to have input impedance below 10:. Measurements showed a peaking time of 14ns and noise of 450e at zero input capacitance, with a noise slope of 37.4 e/pF. The sensitivity of 8mV/fC remains almost unchanged up to a detector ca...

Previously reported wideband CMOS low-noise amplifiers (LNAs) have difficulty in achieving both wideband input impedance matching and low noise performance at low power consumption and low supply voltage. We present a transformer noise-canceling wideband CMOS LNA based on a common-gate topology. The transformer, composed of the input and shunt-peaking inductors, partly cancels the noise origina...