# US 2016/0261237 A1 · Distributed amplifier > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2016/0261237 A1 - Document ID: US20160261237A1 - Status: Published application - Kind: A1 - Application number: 15/045,860 - Filed: 2016-02-17 - Published: 2016-09-08 - Earliest claimed: 2015-03-06 - Assignees: Fujitsu Limited - Applicants: Fujitsu Limited - Inventors: Masaru Sato; Naoko Kurahashi - Web page: https://patentgrep.com/patent/US20160261237A1 ## CPC - H03F 1/0205: {in transistor amplifiers} - H03F 1/18: by use of distributed coupling {, i.e. distributed amplifiers (distributed amplifiers using coupling networks with distributed constants H03F3/605)} - H03F 1/42: Modifications of amplifiers to extend the bandwidth - H03F 1/56: Modifications of input or output impedances, not otherwise provided for - H03F 3/193: with field-effect devices (H03F3/195 takes precedence) - H03F 3/195: in integrated circuits - H03F 3/604: {using FET's} - H03F 3/607: {using FET's} - H03F 3/72: Gated amplifiers, i.e. amplifiers which are rendered operative or inoperative by means of a control signal - 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} - H03F 1/07: Doherty-type amplifiers - H03F 2200/27: A biasing circuit node being switched in an amplifier circuit - H03F 2200/315: the loading circuit of an amplifying stage comprising a transmission line - H03F 2200/36: the amplifier comprising means for increasing the bandwidth - H03F 2200/42: the input to the amplifier being made by capacitive coupling means - H03F 2200/423: Amplifier output adaptation especially for transmission line coupling purposes, e.g. impedance adaptation - H03F 2200/451: the amplifier being a radio frequency amplifier - H03F 2200/48: the output of the amplifier being coupled out by a capacitor - H03F 2200/519: the bias or supply voltage or current of the drain side of a FET amplifier being controlled to be on or off by a switch - H03F 2200/555: A voltage generating circuit being realised for biasing different circuit elements - H03F 2200/75: the amplifier stage being a common source configuration MOSFET - H03F 2203/7227: the gated amplifier being switched on or off by a switch in the supply circuit of the amplifier - H03F: AMPLIFIERS ## Abstract A distributed amplifier includes: an input-side transmission line; M amplification circuits; M output-side transmission lines; and a combination circuit configured to combine outputs of the M output-side transmission lines; wherein the input-side transmission line has an input-side serial line formed by connecting in series MxN unit transmission lines each including the same line length, and an input-side terminating resistor, the M amplification circuits each includes N amplifiers and the N amplifiers of the i-th amplification circuit take the input node of the ((k−1) M+i)-th input-side transmission line to be the input, and the output-side transmission line includes an output-side serial line including N transmission lines each being connected in series between the neighboring outputs of the N amplifiers and each having a line width in which the phase of the output of the amplifier in each stage agrees with one another. ## Claims ### Claim 1 A distributed amplifier comprising: an input-side transmission line; M (M: integer not less than 2) amplification circuits; M output-side transmission lines provided in accordance with the M amplification circuits; and a combination circuit configured to combine outputs of the M output-side transmission lines; wherein the input-side transmission line includes an input-side serial line formed by connecting in series M×N (N: integer not less than 2) unit transmission lines each including the same line length, and an input-side terminating resistor, the M amplification circuits each includes N amplifiers and the N amplifiers of the i-th (i: integer not less than 1 and not more than M) amplification circuit take the input node of the ((k−1)M+i)-th (k: integer not less than 1 and not more than N) input-side transmission line to be the input, and the output-side transmission line includes an output-side serial line including N transmission lines each being connected in series between the neighboring outputs of the N amplifiers and each including a line width with which the phase of the output of the amplifier in each stage agrees to one another. ### Claim 2 (depends on 1) The distributed amplifier according to claim 1, wherein each transmission line of the output-side transmission line includes a line length M times the line length of the unit transmission line. ### Claim 3 (depends on 1) The distributed amplifier according to claim 1, wherein the combination circuit includes a phase adjustment unit configured to match the phase of the output of each of the M output-side serial lines with one another. ### Claim 4 (depends on 2) The distributed amplifier according to claim 2, wherein the combination circuit includes a phase adjustment unit configured to match the phase of the output of each of the M output-side serial lines with one another. ### Claim 5 (depends on 1) The distributed amplifier according to claim 1, wherein each of the N transmission lines of the output-side transmission line includes a line width that is wider than the line width in the previous stage. ### Claim 6 (depends on 2) The distributed amplifier according to claim 2, wherein each of the N transmission lines of the output-side transmission line includes a line width that is wider than the line width in the previous stage. ### Claim 7 (depends on 3) The distributed amplifier according to claim 3, wherein each of the N transmission lines of the output-side transmission line includes a line width that is wider than the line width in the previous stage. ### Claim 8 (depends on 4) The distributed amplifier according to claim 4, wherein each of the N transmission lines of the output-side transmission line includes a line width that is wider than the line width in the previous stage. ### Claim 9 (depends on 5) The distributed amplifier according to claim 5, wherein each of the N transmission lines of the output-side transmission line includes a line width twice the line width in the previous stage. ### Claim 10 (depends on 8) The distributed amplifier according to claim 8, wherein each of the N transmission lines of the output-side transmission line includes a line width twice the line width in the previous stage. ### Claim 11 (depends on 1) The distributed amplifier according to claim 1, wherein at least one of the M amplification circuits and the M output-side transmission lines is capable of switching between operating and non-operating by a switch circuit. ### Claim 12 (depends on 10) The distributed amplifier according to claim 10, wherein at least one of the M amplification circuits and the M output-side transmission lines is capable of switching between operating and non-operating by a switch circuit. ### Claim 13 (depends on 11) The distributed amplifier according to claim 11, wherein the switch circuit includes: a bias switch circuit configured to switch bias voltages that are supplied to the transmission line in the initial stage of the output-side transmission line; and a DC-cut capacitance element that is provided between the output in the final stage of the output-side transmission line and the combination circuit. ### Claim 14 (depends on 12) The distributed amplifier according to claim 12, wherein the switch circuit includes: a bias switch circuit configured to switch bias voltages that are supplied to the transmission line in the initial stage of the output-side transmission line; and a DC-cut capacitance element that is provided between the output in the final stage of the output-side transmission line and the combination circuit.