# US 9,437,928 B2 · Feeding matching apparatus of multiband antenna, multiband antenna, and radio communication device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,437,928 B2 - Document ID: US9437928B2 - Status: Granted - Kind: B2 - Application number: 14/143,367 - Filed: 2013-12-30 - Published: 2014-07-17 - Granted: 2016-09-06 - Earliest claimed: 2013-01-16 - Assignees: Huawei Device Co., Ltd. - Applicants: Huawei Device Co., Ltd. - Inventors: Yuanpeng Li; Hanyang Wang; Yafang Yu; Meng Hou - Web page: https://patentgrep.com/patent/US9437928B2 ## CPC - H01Q 5/328: between a radiating element and ground - H01Q 1/241: {used in mobile communications, e.g. GSM (H01Q1/247, H01Q1/248 take precedence)} - H01Q 1/48: Earthing means; Earth screens; Counterpoises - H01Q 5/314: using frequency dependent circuits or components, e.g. trap circuits or capacitors - H01Q 5/335: at the feed, e.g. for impedance matching - H01Q 9/04: Resonant antennas - H01Q 13/08: Radiating ends of two-conductor microwave transmission lines, e.g. of coaxial lines, of microstrip lines - H04B 1/0057: {using diplexing or multiplexing filters for selecting the desired band} - H04B 1/0458: {Arrangements for matching and coupling between power amplifier and antenna or between amplifying stages (matching circuits in general H03H)} - H04B 1/18: Input circuits, e.g. for coupling to an antenna or a transmission line (coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H) - H01P 1/2039: {Galvanic coupling between Input/Output} - H01P 1/2135: {using strip line filters (H01P1/2131 takes precedence)} - H01P 5/12: Coupling devices having more than two ports (H01P5/04 takes precedence) - H01Q: ANTENNAS, i.e. RADIO AERIALS (radiators or antennas for microwave heating H05B6/72) - H04B: TRANSMISSION - H01P: WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE (operating at optical frequencies G02B) ## Abstract The present disclosure relates to the field of antenna technologies and discloses a feeding matching apparatus of a multiband antenna, a multiband antenna, and a radio communication device to improve a bandwidth and efficiency of a lower frequency band. The feeding matching apparatus of a multiband antenna includes: a grounding portion; a feeding portion connected to a signal source, where a signal of the signal source is input into the feeding portion; and two or more ground cable branches with different lengths, where one end of each ground cable branch is electrically connected to the feeding portion, the other end is electrically connected to the grounding portion, at least one ground cable branch is connected in series to a signal filtering component, and the signal filtering component is capable of preventing a signal lower than a frequency point corresponding to the signal filtering component from passing through it. ## Claims ### Claim 1 A multiband antenna, comprising: one or more radiating portions; a grounding portion; a feeding portion coupled to the radiating portions, wherein each radiating portion is configured to transmit a signal to the feeding portion and receive a signal transmitted from the feeding portion; a first ground cable branch, wherein one end of the first ground cable branch is electrically coupled to the feeding portion, the other end of the first ground cable branch is electrically coupled to the grounding portion, wherein the first ground cable branch is coupled in series to a first signal filtering component, the first signal filtering component terminates a transmission of a signal having a frequency lower than a frequency point of the first signal filtering component; and a second ground cable branch, wherein one end of the second ground cable branch is electrically coupled to the feeding portion, the other end of the second ground cable branch is electrically coupled to the grounding portion, wherein the second ground cable branch is coupled in series to a second signal filtering component, the second signal filtering component terminates a transmission of a signal having a frequency lower than a frequency point of the second signal filtering component; wherein a length of the first ground cable branch is shorter than a length of the second ground cable branch, and the frequency point of the first signal filtering component is higher than the frequency point of the second signal filtering component. ### Claim 2 (depends on 1) The multiband antenna according to claim 1, wherein the first signal filtering component is a high-pass filter and the second signal filtering component is a high-pass filter. ### Claim 3 (depends on 2) The multiband antenna according to claim 2, wherein the high-pass filter is an inductor. ### Claim 4 (depends on 2) The multiband antenna according to claim 2, wherein the high-pass filter is a capacitor. ### Claim 5 (depends on 2) The multiband antenna according to claim 2, wherein the high-pass filter is formed by connecting in series a capacitor to an inductor. ### Claim 6 (depends on 2) The multiband antenna according to claim 2, wherein the high-pass filter is formed by connecting in parallel a capacitor to an inductor. ### Claim 7 (depends on 2) The multiband antenna according to claim 2, wherein the high-pass filter is a micro-strip line. ### Claim 8 (depends on 1) The multiband antenna according to claim 1, wherein the radiating portions comprises a first radiating portion and a second radiating portion, wherein a length of the first radiating portion is shorter than a length of the second radiating portion, wherein the first radiating portion matches the first ground cable branch and the second radiating portion matches the second ground cable branch. ### Claim 9 A radio communication device, comprising a multiband antenna, wherein the multiband antenna comprises: one or more radiating portions; a grounding portion; a feeding portion coupled to the radiating portions, wherein each radiating portion is configured to transmit a signal to the feeding portion and receive a signal transmitted from the feeding portion; a first ground cable branch, wherein one end of the first ground cable branch is electrically coupled to the feeding portion, the other end of the first ground cable branch is electrically coupled to the grounding portion, wherein the first ground cable branch is coupled in series to a first signal filtering component, the first signal filtering component terminates a transmission of a signal having a frequency lower than a frequency point of the first signal filtering component; and a second ground cable branch, wherein one end of the second ground cable branch is electrically coupled to the feeding portion, the other end of the second ground cable branch is electrically coupled to the grounding portion, wherein the second ground cable branch is coupled in series to a second signal filtering component, the second signal filtering component terminates a transmission of a signal having a frequency lower than a frequency point of the second signal filtering component; wherein a length of the first ground cable branch is shorter than a length of the second ground cable branch, and the frequency point of the first signal filtering component is higher than the frequency point of the second signal filtering component. ### Claim 10 (depends on 9) The radio communication device according to claim 9, wherein the radiating portions comprises a first radiating portion and a second radiating portion, wherein a length of the first radiating portion is shorter than a length of the second radiating portion, wherein the first radiating portion matches the first ground cable branch and the second radiating portion matches the second ground cable branch. ### Claim 11 (depends on 9) The radio communication device according to claim 9, wherein both the first signal filtering component and the second signal filtering component are high-pass filters. ### Claim 12 (depends on 11) The radio communication device according to claim 11, wherein the high-pass filter is an inductor. ### Claim 13 (depends on 11) The radio communication device according to claim 11, wherein each of the high-pass filters is a capacitor. ### Claim 14 (depends on 11) The radio communication device according to claim 11, wherein each of the high-pass filters is formed by connecting in series a capacitor to an inductor. ### Claim 15 (depends on 11) The radio communication device according to claim 11, wherein each of the high-pass filters is formed by connecting in parallel a capacitor to an inductor. ### Claim 16 (depends on 11) The radio communication device according to claim 11, wherein each of the high-pass filters is a micro-strip line.