现用于4G基站的介质腔体滤波器都采用TE01δ模介质谐振腔，虽然其品质因数Q值很高，但体积较大。为了小型化介质腔体滤波器，创新性地使用了TM010模介质谐振腔，虽然其Q值比较低，但同样能满足高带外抑制的要求。对TM010模介质谐振腔的端口耦合和两腔之间的磁耦合、电耦合进行分析研究，创新性地使用了介质窗的形式产生电耦合，避免了使用飞杆，易于加工，降低制造成本。最后设计了一个8腔TM010模准椭圆函数介质腔体带通滤波器，在通带(TD-LTE频带，2570~2620 MHz)两端分别设计两个传输零点以提高带外抑制。调试结果表明，TM010模介质腔体滤波器不仅能满足低插损、高带外抑制的要求，而且其体积大幅度缩小。

The dielectric cavity filter used for 4G base station usually adopts TE01δ mode dielectric resonators. Its quality factor Q value is very high, but its size is relatively large. In order to miniaturize the dielectric cavity filter, TM010 mode dielectric resonator is innovatively used. Although its Q value is relatively low, it can also meet the requirements of high band rejections. In this paper, the port coupling, magnetic coupling and electric coupling between two resonators are analyzed. Dielectric openings are innovatively used to create electric couplings, which are easy to machine and reduce manufacturing costs. Besides, an 8-pole quasi-elliptic function filter with two pairs of transmission zeros that can improve the close-to-band rejection slopes is designed and its passband is 2570 MHz to 2620 MHz, TD-LTE band. The debugging results show that the TM010 mode dielectric cavity filter can not only meet the requirements of low insertion loss and high band rejections, but also reduce its size greatly.