High-frequency Low-noise Surface Transverse Wave Oscillator

The application of surface acoustic wave resonator is extensively wide, as high stability of the fixed frequency oscillators, narrow band modulation oscillators, narrow band voltage control oscillators ,low phase noise resources,and so on. Surface acoustic wave resonator on quartz has a series of advantages, a good range of operation temperature, good temperature-frequency characteristic, small size, good reliability, especially the advantage of low vibration of surface transverse resonator oscillator, which is very important for its applying in motile communication, radar, satellite system and remote control remote test.The research of the dissertation puts emphasis on creating and analyzing the modal of fundamental structure of STW devices and the designing of STWO circuit, employs the formulation of theory analysis together with manufacture of actual devices. Firstly, creating resonator modal basing surface transverse wave transmission fundamental theory,compiling the program of design STWR, solving the grating reflection coefficient with the period of grating,simulating the insert loss with the parameters of resonator structure,accomplishing the mask. Secondly, analyzing the source of phase noise,exploring the method of reducing phase noise,constructing the oscillator circuit. Thirdly, studying the influence of the sputtering parameter on the Al film character, completing lithography and etching of the 3-4μm line width.The phase noise feature of the finished STWO is very good with low insert loss STW resonators which have quality of 700. The center frequency and the insertion loss of SAW device are 316.7 MHz and 9.8 dB. The output power of oscillator using STW device is 3.16 dBM@314.8 MHz while its phase noise is -80 dBc/Hz@1KHz.. With the development of design of resonator and oscillator circuit, we believe the STWO can achieve higher features.