# US 11,909,438 B2 · Digital beacon for free-space optical communication > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,909,438 B2 - Document ID: US11909438B2 - Status: Granted - Kind: B2 - Application number: 17/708,768 - Filed: 2022-03-30 - Published: 2023-04-13 - Granted: 2024-02-20 - Earliest claimed: 2021-10-07 - Assignees: Lumentum Operations LLC - Applicants: Lumentum Operations LLC - Inventors: Ali Salehiomran - Web page: https://patentgrep.com/patent/US11909438B2 ## CPC - H04B 10/11: Arrangements specific to free-space transmission, i.e. transmission through air or vacuum - H04B 10/118: specially adapted for satellite communication - H04B: TRANSMISSION ## Abstract A transmitter may include a digital signal processor (DSP) to generate an electrical signal associated with a beacon and a data signal. The transmitter may include an electro-optical component to convert the electrical signal to an optical signal to be transmitted by the transmitter. The beacon and the data signal may be on a common wavelength in the optical signal. A power of the beacon within the optical signal may be based on a value of an amplitude modulation factor applied to the beacon by the DSP in association with generating the electrical signal. ## Claims ### Claim 1 A transmitter, comprising: a digital signal processor (DSP) to generate an electrical signal associated with a beacon and a data signal; and an electro-optical component to convert the electrical signal to an optical signal to be transmitted by the transmitter, wherein the beacon and the data signal are on a common wavelength in the optical signal, wherein a power of the beacon within the optical signal is based on a value of an amplitude modulation factor applied to the beacon by the DSP in association with generating the electrical signal, and wherein the DSP is configured to at least one of: increase the value of the amplitude modulation factor to increase the power of the beacon within the optical signal, or decrease the value of the amplitude modulation factor to decrease the power of the beacon within the optical signal. ### Claim 2 (depends on 1) The transmitter of claim 1, wherein the beacon includes at least two tones, each tone associated with a respective amplitude modulation factor and a respective frequency factor, wherein the respective frequency factors of the at least two tones are different. ### Claim 3 (depends on 1) The transmitter of claim 1, wherein the data signal and the beacon are communicated via a single connection between the DSP and the electro-optical component. ### Claim 4 (depends on 1) The transmitter of claim 1, wherein the transmitter is included in a free-space optical communication system. ### Claim 5 (depends on 1) The transmitter of claim 1, wherein the transmitter includes a single light source associated with transmitting the optical signal on the common wavelength. ### Claim 6 (depends on 1) The transmitter of claim 1, wherein, in association with performing pointing, acquisition, and tracking (PAT), the DSP is configured to increase the value of the amplitude modulation factor to increase the power of the beacon within the optical signal during a first PAT phase. ### Claim 7 (depends on 6) The transmitter of claim 6, wherein the DSP is further to hold a value of the data signal at a constant value during the first PAT phase. ### Claim 8 (depends on 6) The transmitter of claim 6, wherein the DSP is configured to decrease the value of the amplitude modulation factor to decrease the power of the beacon within the optical signal during a second PAT phase. ### Claim 9 (depends on 8) The transmitter of claim 8, wherein the DSP is further to vary a value of the data signal to represent data to be transmitted in the optical signal during the second PAT phase. ### Claim 10 (depends on 8) The transmitter of claim 8, wherein the DSP is further to: hold a value of the data signal at a constant value during the first PAT phase, and vary a value of the data signal to represent data to be transmitted in the optical signal during the second PAT phase. ### Claim 11 A method, comprising: generating, by a digital signal processor (DSP) of a transmitter, an electrical signal associated with a beacon and a data signal; converting, by an electro-optical component of the transmitter, the electrical signal to an optical signal, wherein the optical signal includes the beacon and the data signal on a common wavelength; transmitting, by the transmitter, the optical signal, wherein a power of the beacon within the optical signal is based on a value of an amplitude modulation factor applied to the beacon by the DSP in association with generating the electrical signal; and in association with performing pointing, acquisition, and tracking (PAT), at least one of: increasing the value of the amplitude modulation factor to increase the power of the beacon within the optical signal, or decreasing the value of the amplitude modulation factor to decrease the power of the beacon within the optical signal. ### Claim 12 (depends on 11) The method of claim 11, wherein the beacon includes at least two tones, each tone associated with a respective amplitude modulation factor and a respective frequency factor, wherein the respective frequency factors of the at least two tones are different. ### Claim 13 (depends on 11) The method of claim 11, wherein increasing the value of the amplitude modulation factor to increase the power of the beacon in the optical signal is performed during a first PAT phase. ### Claim 14 (depends on 13) The method of claim 13, further comprising holding a value of the data signal at a constant value during the first PAT phase. ### Claim 15 (depends on 13) The method of claim 13, wherein decreasing the value of the amplitude modulation factor to decrease the power of the beacon in the optical signal is performed during a second PAT phase. ### Claim 16 (depends on 15) The method of claim 15, further comprising varying a value of the data signal to represent data to be transmitted in the optical signal during the second PAT phase. ### Claim 17 (depends on 15) The method of claim 15, further comprising: holding a value of the data signal at a constant value during the first PAT phase; and varying a value of the data signal to represent data to be transmitted in the optical signal during the second PAT phase. ### Claim 18 A transmitter, comprising: a digital signal processor (DSP) to generate an electrical signal associated with a beacon and a data signal; and an electro-optical component to convert the electrical signal to an optical signal to be transmitted by the transmitter, wherein the beacon and the data signal are communicated via a single connection between the DSP and the electro-optical component, wherein a power of the beacon within the optical signal is based on a value of an amplitude modulation factor applied to the beacon by the DSP in association with generating the electrical signal, and wherein, in association with performing pointing, acquisition, and tracking (PAT), the DSP is configured to at least one of: increase the value of the amplitude modulation factor to increase the power of the beacon within the optical signal, or decrease the value of the amplitude modulation factor to decrease the power of the beacon within the optical signal. ### Claim 19 (depends on 18) The transmitter of claim 18, wherein the beacon includes at least two tones, each tone associated with a respective amplitude modulation factor and a respective frequency factor, wherein the respective frequency factors of the at least two tones are different. ### Claim 20 (depends on 18) The transmitter of claim 18, wherein the transmitter includes a single light source associated with transmitting the optical signal on a common wavelength.