介绍了一种可满足第二代北斗客户端用B3波段载频滤波的声表面波(SAW)射频滤波器。该滤波器采用“5换能器纵向耦合结构＋谐振器”的混合型设计方案, 在充分考虑了SMD3030A封装及键合引线寄生影响后, 成功研制出-1 dB带宽35 MHz、插入损耗2.2 dB、矩形系数1.9的滤波器产品。结果表明, 仿真与实测吻合性较好, 证明了该设计方案的可行性。

In this article, a type of RF SAW filter that can meet the requirements of the B3 band carrier frequency filtering of the second generation Beidou end-users is introduced. A hybrid design scheme of 5-transducer longitudinal coupling structure plus resonator structure is adopted in the filter. The filter with -1 dB bandwidth of 35 MHz, insertion loss of 2.2 dB and shape factor of 1.9 has been developed after comprehensively considering the parasitic effects of the SMD3030A package and the bonding wires. The comparison shows that the simulation and measurement results are in good agreement, which proves the proposed design scheme is practicable.