US 11,909,086 B2
Dielectric filter, duplexer, and communications device
Dan Liang, Shanghai (CN); Xiaofeng Zhang, Kista (SE); and Zheng Cui, Dongguan (CN)
Assigned to Huawei Technologies Co., Ltd., Shenzhen (CN)
Filed by Huawei Technologies Co., Ltd., Shenzhen (CN)
Filed on Jun. 25, 2021, as Appl. No. 17/359,166.
Application 17/359,166 is a continuation of application No. PCT/CN2018/124006, filed on Dec. 26, 2018.
Prior Publication US 2021/0328315 A1, Oct. 21, 2021
Int. Cl. H01P 1/20 (2006.01); H01P 1/212 (2006.01); H01P 5/12 (2006.01); H04B 1/40 (2015.01)
CPC H01P 1/2002 (2013.01) [H01P 1/212 (2013.01); H01P 5/12 (2013.01); H04B 1/40 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A dielectric filter comprising:
a dielectric body, wherein a surface of the dielectric body is covered with a conductive layer;
a wideband filtering structure comprising a groove and at least one first resonator, wherein:
the groove is disposed on a first surface of the dielectric body and is configured to adjust a frequency position of the passband of the wideband filtering structure;
the first resonator comprises a through hole and an open loop, the through hole penetrates the bottom of the groove and a second surface of the dielectric body, and a hole wall of the through hole is covered with the conductive layer;
the open loop is located on a bottom surface of the groove and is disposed around an opening of the through hole; and
a side surface of the groove and a part, other than the open loop, of the bottom surface of the groove are covered with the conductive layer;
a narrowband filtering structure comprising at least one second resonator, which comprises a blind hole disposed on the first surface or the second surface of the dielectric body, wherein a hole wall and a bottom surface of the blind hole are covered with the conductive layer; and the first surface and the second surface of the dielectric body are disposed oppositely;
wherein both the wideband filtering structure and the narrowband filtering structure are disposed in the dielectric body; a passband of the narrowband filtering structure is located within a passband of the wideband filter structure.