一种扇形结构小型化中频声表面波滤波器

Development of Miniature IF SAW Filter with Sector Structure

该文研究了一种扇形结构的声表面波设计技术并分析了其工作原理及加权方式,为某电台接收机设计并制作了一款中心频率为374 MHz、-3 dB带宽大于17 MHz、插入损耗小于9.5 dB、通带波纹小于1 dB、带外抑制大于40 dB(10~352 MHz)的器件。将该器件封装在表贴SMD3838小型外壳中,其满足性能指标。结果表明,该器件首次突破了扇形结构中频声表面波滤波器在表贴SMD3838封装的研制,表明扇形结构声表面波滤波器产品实现小型化的可行性。

In this paper,the design technology of SAW filter with sector structure is studied and its operating principle and weighting method are also analyzed.A filter for radio receiver has been designed,which has a center frequency of 374 MHz,-3 dB bandwidth of greater than 17 MHz,insertion loss of less than 9.5 dB,passband ripple of less than 1 dB and out of band rejection of greater than 40 dB(10~352 MHz).The device is packaged in the SMD3838 small enclosure and meets the specifications.The results show that the development of IF SAW filter with sector structure in SMD3838 packaging has been broken through for the first time,indicating the feasibility of miniaturization of SAW filter with sector structure.