# US 2021/0175853 A1 · Power amplifier > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0175853 A1 - Document ID: US20210175853A1 - Status: Published application - Kind: A1 - Application number: 16/953,890 - Filed: 2020-11-20 - Published: 2021-06-10 - Earliest claimed: 2019-12-10 - Assignees: Murata Manufacturing Co., Ltd. - Applicants: Murata Manufacturing Co., Ltd. - Inventors: Kiichiro TAKENAKA - Web page: https://patentgrep.com/patent/US20210175853A1 ## CPC - H01P 5/185: {Edge coupled lines} - H03F 1/0288: {using a main and one or several auxiliary peaking amplifiers whereby the load is connected to the main amplifier using an impedance inverter, e.g. Doherty amplifiers} - H01P 5/16: Conjugate devices, i.e. devices having at least one port decoupled from one other port - H03F 3/211: {using a combination of several amplifiers (H03F3/60 takes precedence)} - H03F 3/245: {with semiconductor devices only} - H03F 2200/192: A hybrid coupler being used at the input of an amplifier circuit - H03F 2200/198: A hybrid coupler being used as coupling circuit between stages of an amplifier circuit - H03F 2200/204: A hybrid coupler being used at the output of an amplifier circuit - H03F 2200/372: Noise reduction and elimination in amplifier - H03F 2200/451: the amplifier being a radio frequency amplifier - H01P: WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE (operating at optical frequencies G02B) - H03F: AMPLIFIERS ## Abstract A power amplifier includes a 3-dB coupler which splits a first signal into a second signal and a third signal lagging behind the second signal by 90°, a carrier amplifier, a peak amplifier, and a hybrid coupler. The carrier amplifier amplifies the second signal and outputs a fourth signal when the first-signal power level is a first level or higher. The peak amplifier amplifies the third signal and outputs a fifth signal when the first-signal power level is a second level or higher, which is higher than the first level. The hybrid coupler includes a first transmission line receiving the fourth signal at its first terminal, and a second transmission line receiving the fifth signal at its first terminal and being open at its second terminal. The first transmission line outputs, from its second terminal, an amplified first signal obtained by combining the fourth and fifth signals. ## Claims ### Claim 1 A power amplifier comprising: a splitter configured to split a first signal into a second signal and a third signal, the third signal being delayed from the second signal by 90°; a first amplifier configured to amplify the second signal and to output a fourth signal when a power level of the first signal is equal to or greater than a first level; a second amplifier configured to amplify the third signal and to output a fifth signal when the power level of the first signal is equal to or greater than a second level, the second level being greater than the first level; and a hybrid coupler comprising a first transmission line and a second transmission line, wherein the first transmission line is configured to receive the fourth signal at a first terminal of the first transmission line, wherein the second transmission line is configured to receive the fifth signal at a first terminal of the second transmission line, wherein the second transmission line is open at a second terminal of the second transmission line, and wherein the first transmission line is configured to output, from a second terminal of the first transmission line, an amplified first signal, the amplified first signal being a combination of the fourth signal and the fifth signal. ### Claim 2 (depends on 1) The power amplifier according to claim 1, wherein the hybrid coupler further comprises a dielectric between the first transmission line and the second transmission line. ### Claim 3 (depends on 1) The power amplifier according to claim 1, wherein the hybrid coupler, the first amplifier, and the second amplifier are on a same substrate. ### Claim 4 (depends on 2) The power amplifier according to claim 2, wherein the hybrid coupler, the first amplifier, and the second amplifier are on a same substrate. ### Claim 5 A power amplifier comprising: a splitter configured to split a first signal into a second signal and a third signal, the third signal being delayed from the second signal by equal to or greater than 90° and less than 180°; a first amplifier configured to amplify the second signal and to output a fourth signal when a power level of the first signal is equal to or greater than a first level; a second amplifier configured to amplify the third signal and to output a fifth signal when the power level of the first signal is equal to or greater than a second level, the second level being greater than the first level; and a hybrid coupler comprising a first transmission line and a second transmission line, wherein the first transmission line is configured to receive the fourth signal at a first terminal of the first transmission line, wherein the second transmission line is configured to receive the fifth signal at a first terminal of the second transmission line, wherein the second transmission line is open at a second terminal of the second transmission line, and wherein the first transmission line is configured to output, from a second terminal of the first transmission line, an amplified first signal, the amplified first signal being a combination of the fourth signal and the fifth signal. ### Claim 6 (depends on 5) The power amplifier according to claim 5, wherein the third signal is delayed from the second signal by 120°. ### Claim 7 (depends on 5) The power amplifier according to claim 5, wherein the hybrid coupler further comprises a dielectric between the first transmission line and the second transmission line. ### Claim 8 (depends on 6) The power amplifier according to claim 6, wherein the hybrid coupler further comprises a dielectric between the first transmission line and the second transmission line. ### Claim 9 (depends on 5) The power amplifier according to claim 5, wherein the hybrid coupler, the first amplifier, and the second amplifier are on a same substrate. ### Claim 10 (depends on 6) The power amplifier according to claim 6, wherein the hybrid coupler, the first amplifier, and the second amplifier are on a same substrate. ### Claim 11 (depends on 7) The power amplifier according to claim 7, wherein the hybrid coupler, the first amplifier, and the second amplifier are on a same substrate.