Low Loss, High Q Saw Resonators, And Low Phase Noise Saw Oscillators,

Surface acoustic wave is a elasticity wave on the solid substrate.Its velocity has 105 lower than light's. Early on century 19,the theory of surface acoustic wave has been exist,but it was been experiment that used the figure of metal interdigital transducer in order to activing and detecting surface acoustic wave. To utilize property of SAWs propagating,it can be made including delay lines,passband filters, oscillators and pitch filters.Surface transverse wave(STW) was used the configurature of reflective metal- strip grating between the two interdigital transducers,and made the shear horizotal (SH) wave on the surface of the piezoelectric substrate,but not to deep in. Surface transverse wave has the 1.6 high frequency than Rayleigh type surface acoustic wave (Using the same technology the frequency of devices of STW has about 1.6 high frequency than Rayleigh type surface acoustic wave).The paper introduces the theory,design parament,technology and result expeiment of surface acoustic wave(includes Rayleigh surface acoustic wave and surface transverse wave,simple STW) with low insertion loss,high Q and researches the high frequency,low phase noise oscillator with 1GHz STW resonator as frequency element. And describes measurement method and finally experimantal result of the low phase noise surface acoustic wave oscillator.At present the manufacture of surface acoustic wave use the technology of the final submicron.A series of the devices of low insertion loss,high Q SAW Rayleigh surface acoustic wave resonators or STWs that insertion loss has less than 5dB,load quality factor(QL) is more than 1000 on the quartz piezoelectric with zero of first temperature factor in the research.These difference frequencies are 60MHz, 280MHz, 739MHz and 1GHz of normal frequency and at also surface acoustic wave.Using 1.25dB noise factor amplifier, careful design curcuit,good setting printed curcuit board,and using the 1GHz surface transverse wave resonator as frequency element, researching the low phase noise surface acoustic wave with sideband phase noise near–120dBc/Hz deviating 1KHz on carrier,spurious suppress with 80dB.