# US 12,224,783 B2 · Broadband active coupling method and device > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,224,783 B2 - Document ID: US12224783B2 - Status: Granted - Kind: B2 - Application number: 17/586,906 - Filed: 2022-01-28 - Published: 2023-08-03 - Granted: 2025-02-11 - Earliest claimed: 2022-01-28 - Assignees: Ciena Corporation - Applicants: Ciena Corporation - Inventors: Yuriy Greshishchev; Aravinthan Vigneswaran - Web page: https://patentgrep.com/patent/US12224783B2 ## CPC - H04B 1/0483: {Transmitters with multiple parallel paths} - H03F 1/26: Modifications of amplifiers to reduce influence of noise generated by amplifying elements - H03F 1/56: Modifications of input or output impedances, not otherwise provided for - H03F 3/195: in integrated circuits - H03F 3/245: {with semiconductor devices only} - H03F 3/45188: {Non-folded cascode stages} - 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) - H03F 2200/294: the amplifier being a low noise amplifier [LNA] - H03F 2200/451: the amplifier being a radio frequency amplifier - H04B 2001/0491: {with frequency synthesizers, frequency converters or modulators} - H04B: TRANSMISSION - H03F: AMPLIFIERS ## Abstract Described are broadband active coupling circuits and methods. A broadband active coupling circuit includes a high-pass circuit configured to provide a high frequency response for a broadband signal and a low-pass circuit connected in parallel with the high-pass circuit. The low-pass circuit is configured to provide a low frequency response for the broadband signal, where the low-pass circuit includes an active circuit configured to minimally impact the high frequency response provided by the high-pass circuit. ## Claims ### Claim 1 A broadband active coupling circuit comprising: a high-pass circuit configured to provide a high frequency response for a broadband signal; and a low-pass circuit connected in parallel with the high-pass circuit, the low-pass circuit configured to provide a low frequency response for the broadband signal, wherein the low-pass circuit includes an active circuit configured to not impact the high frequency response provided by the high-pass circuit. ### Claim 2 (depends on 1) The broadband active coupling circuit of claim 1, wherein the high-pass circuit further comprising a capacitor selected to match a given integrated circuit (IC) technology to provide the high frequency response. ### Claim 3 (depends on 1) The broadband active coupling circuit of claim 1, wherein the low frequency response can range from a first frequency which is at or near a frequency of the high frequency response to a second frequency, where the second frequency is less than the first frequency. ### Claim 4 (depends on 3) The broadband active coupling circuit of claim 3, wherein the second frequency is at or near zero hertz. ### Claim 5 (depends on 1) The broadband active coupling circuit of claim 1, wherein the low-pass circuit further comprising a resistor-capacitor circuit coupled to the active circuit, the resistor-capacitor circuit configured to receive the broadband signal, wherein the active circuit and the resistor-capacitor circuit are configured to control the low frequency response frequency and phase response and broadband active coupler transfer function. ### Claim 6 (depends on 1) The broadband active coupling circuit of claim 1, wherein the broadband active coupling circuit is a single-ended broadband active coupling circuit. ### Claim 7 (depends on 1) The broadband active coupling circuit of claim 1, wherein the active circuit is a voltage-to-current circuit. ### Claim 8 (depends on 1) The broadband active coupling circuit of claim 1, wherein the active circuit further comprising a low pass gain control circuit and an isolation circuit configured to provide minimum distortion with respect to the high frequency response and limit amplitude and phase variation in a transition frequency region between the low frequency response and the high frequency response. ### Claim 9 (depends on 1) The broadband active coupling circuit of claim 1, wherein the broadband active coupling circuit is a differential broadband active coupling circuit. ### Claim 10 (depends on 9) The broadband active coupling circuit of claim 9, wherein the differential broadband active coupling circuit is a direct current coupled differential circuit. ### Claim 11 A method for broadband active coupling, the method comprising: passing, from a transmitter to a receiver via a high-pass channel, upper band frequencies of a broadband signal, the upper band frequencies starting from a first high-pass corner frequency up to higher frequencies; and passing, from the transmitter to the receiver via a low-pass channel provided in parallel to the high-pass channel, lower band frequencies of the broadband signal, the lower band frequencies starting at or near the first high-pass corner frequency down to a second high-pass corner frequency, wherein the low-pass channel includes active components configured to isolate processing by the low-pass channel on the high-pass channel. ### Claim 12 (depends on 11) The method of claim 11, further comprising selecting capacitor values for the high-pass channel to accommodate integrated circuit technologies used for the transmitter and the receiver. ### Claim 13 (depends on 11) The method of claim 11, wherein the second high-pass corner frequency is at or near zero hertz. ### Claim 14 (depends on 11) The method of claim 11, further comprising generating from the broadband signal a differential input pair; and outputting by the low-pass channel a differential output pair. ### Claim 15 (depends on 11) The method of claim 11, further comprising controlling, by the active components, an amplitude and phase variation in the low-pass channel and in a transition frequency region between the high-pass channel and the low-pass channel. ### Claim 16 A system comprising: a transmitter circuit configured to transmit a broadband signal; a receiver circuit configured to receive the broadband signal via a transmission line; and a two-channel coupling circuit configured to interface between the transmitter circuit and the receiver circuit, the two-channel coupling circuit comprising an upper band channel configured to pass frequencies from the broadband signal starting from an upper band corner frequency up to higher frequencies; and a lower band channel connected in parallel to the upper band channel, the lower band channel configured to pass frequencies starting at or near the upper band corner frequency down to a lower band corner frequency, wherein the lower band channel includes active circuitry configured to mitigate impact on passing of the frequencies by the upper band channel. ### Claim 17 (depends on 16) The system of claim 16, wherein the upper band channel includes a capacitor selected to match a given integrated circuit. ### Claim 18 (depends on 16) The system of claim 16, wherein the lower band corner frequency is at or near zero hertz. ### Claim 19 (depends on 16) The system of claim 16, wherein the two-channel coupling circuit is a differential two-channel coupling circuit. ### Claim 20 (depends on 16) The system of claim 16, wherein the two-channel coupling circuit is a direct current coupled differential two-channel coupling circuit.