Acoustic Wave Delay Line Oscillator Research Articles

Radio frequency response of GaN-based SAW oscillator to UV illumination by the Sun and man-made source

A new solar-blind UV detector based on a GaN surface acoustic wave delay line oscillator is reported. The illumination by an artificial UV source in the presence of sunlight increased the RF spectral line width of the oscillator by almost an order of magnitude, which we attribute to the different noise spectra of these light sources. The output of this detector is a radio signal, which makes it especially attractive for remote sensing applications.

Frequency stability enhancement from carrier-envelope resonance in a surface acoustic wave delay line oscillator

We have built a new injection-locking set-up which allows the study of low frequency noise in an oscillator. The interaction between a driving 100 MHz signal and a surface acoustic wave delay line oscillator undergoing a nonlinear modulational instability is investigated. Driving amplitude is used to control the synchronization range and therefore the frequency stability of a newly discovered carrier-envelope resonance process. In the soliton-locked regime, fundamental and subharmonic steps attached to a Lorentzian shape frequency-amplitude characteristic are found. They are explained thanks to a driven nonlinear Schrödinger model and the joined synchronization map.

Piezoelectric Characteristics of PbZrO3-Based Ceramics around Ferroelectric Phase Transition Temperature

The ferroelectric-ferroelectric transition characteristics of rhombohedral xPbZrO3–yPb(Zn1/3Nb2/3)O3–zPbTiO3 ceramics are described. The temperature dependence of oscillation frequency of a surface acoustic wave delay line oscillator shows an abrupt change of about 2000 ppm/°C and thermal hysteresis around the transition temperature. The ceramics are highly sensitive to temperature variation and electric field. The composition exhibiting a desired transition in the temperature range of -10∼100 °C is possible. These piezoelectric characteristics are useful from the viewpoint of sensor technology.

Surface Acoustic Wave Delay Line Oscillator

This paper describes the use of a SAW delay line as a frequency stabilizing element in an oscillator. An ST cut, X propagating quartz substrate has been used for fabricating a delay line. To overcome the photo-lithographic constraints, double electrode IDTs have been used. This delay line has been incorporated, as a feedback element in an amplifier. The fixed time delay of this delay line, operating in third harmonic mode, is utilized to provide single frequency generation at about 130 MHz, The short term stability is found to be better than 1 in 108.