# US 5,710,648 A · Optical communication system and remote sensor interrogation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,710,648 A - Document ID: US5710648A - Status: Granted - Kind: A - Application number: 08/579,986 - Filed: 1995-12-29 - Granted: 1998-01-20 - Earliest claimed: 1995-12-29 - Assignees: Lucent Technologies Inc. - Inventors: Nicholas J. Frigo - Web page: https://patentgrep.com/patent/US5710648A ## CPC - H04B 10/2587: using a single light source for multiple stations - H04B: TRANSMISSION ## Abstract A sensing system including an optical receiver for receiving downstream optical signals and for converting the downstream optical signals to downstream electrical signals. An optical transducer impresses information in an upstream data signal onto upstream optical signals. At least one sensor responsive to an external stimulus provides sensor information signals. A processor receives the downstream electrical signals and establishes communication channels to at least one communication terminal providing communication information signals, and to the at least one sensor. The at least one terminal and the at least one sensor provide the communication and sensor information signals, respectively, to the processor which forwards the information signals to the optical transducer as the upstream data signal. ## Claims ### Claim 1 A sensing and communication system comprising: an optical receiver for receiving downstream optical signals and for converting the downstream optical signals to downstream electrical signals; an optical transducer for impressing information in an upstream data signal onto upstream optical signals; at least one sensor responsive to an external stimulus for providing sensor information signals, said external stimulus being unrelated to functional operation of the system; and a processor for receiving the downstream electrical signals and for establishing communication channels to at least one communication terminal providing communication information signals, and to the at least one sensor, wherein the at least one terminal and the at least one sensor provide the communication information signals and the sensor information signals, respectively, to the processor which forwards the information signals to the optical transducer as the upstream data signal. ### Claim 2 (depends on 1) A sensing and communication system as recited in claim 1, wherein the optical transducer is a source for converting electrical signals into optical signals. ### Claim 3 (depends on 2) A sensing and communication system as recited in claim 2, wherein the source is a LASER. ### Claim 4 (depends on 2) A sensing and communication system as recited in claim 2, wherein the source is a broadband optical source. ### Claim 5 (depends on 1) A sensing and communication system as recited in claim 1, wherein the downstream optical signal is coupled to the upstream optical signal. ### Claim 6 (depends on 5) A sensing and communication system as recited in claim 5, wherein the upstream optical signal is amplified by the optical transducer. ### Claim 7 (depends on 5) A sensing and communication system as recited in claim 5, wherein the optical transducer modulates the upstream optical signals. ### Claim 8 (depends on 1) A sensing and communication system as recited in claim 1, wherein the at least one sensor is polled by the processor to provide the sensor information signals. ### Claim 9 (depends on 8) A sensing and communication system as recited in claim 8, wherein the at least one sensor is polled in response to a downstream optical signal. ### Claim 10 (depends on 8) A sensing and communication system as recited in claim 8, wherein the processor determines when to poll the at least one sensor. ### Claim 11 (depends on 1) A sensing and communication system as recited in claim 1, wherein the sensor interrupts the processor in response to an external stimulus. ### Claim 12 (depends on 1) A sensing and communication system as recited in claim 1, wherein the processor provides upstream data signals that correspond to a predetermined number in response to a predetermined set of sensor information signals. ### Claim 13 (depends on 1) A sensing and communication system as recited in claim 1, wherein the processor causes an emergency alert signal to be sent as the upstream data signal in response to a predetermined set of sensor information signals. ### Claim 14 (depends on 1) A sensing and communication system as recited in claim 1, wherein the upstream optical signal includes identification information. ### Claim 15 (depends on 1) A sensing and communication system as recited in claim 1, wherein the upstream optical signal causes instructions to be sent on the downstream electrical signal. ### Claim 16 (depends on 1) The sensing and communication system of claim 1, wherein said sensor is selected from the group consisting of an environmental sensor and a security-type sensor. ### Claim 17 (depends on 16) The sensing and communication system of claim 16, wherein said environmental sensor is one of a temperature sensor, a chemical residue sensor, a smoke sensor, a sound sensor, a pressure sensor, a carbon monoxide sensor or a humidity sensor. ### Claim 18 (depends on 16) The sensing and communication system of claim 16 wherein said security-type sensor is one of a motion sensor, a sound sensor or an intrusion sensor. ### Claim 19 A sensing system comprising: an optical coupler for receiving at least a portion of a downstream optical signal and for providing a downstream optical sensor interrogation signal and a downstream communication information signal; a communication device for receiving the downstream communication information signal and for providing an upstream communication information signal; at least one sensor responsive to an external stimulus for providing sensor information signals; an optical signal modification device for receiving the downstream optical sensor interrogation signal and for modifying at least a portion of it to provide an upstream sensed signal in response to the sensor information signals; and an upstream optical coupler for combining the upstream communication information signal and the upstream sensed signal into a composite upstream optical signal. ### Claim 20 (depends on 19) A sensing system as recited in claim 19, wherein the optical coupler comprises a WDM device. ### Claim 21 (depends on 19) A sensing system as recited in claim 19, wherein the at least one sensor is polled by the optical signal modification device in response to the sensor interrogation signal. ### Claim 22 (depends on 19) A sensing system as recited in claim 19, wherein the at least one sensor provides an electrical signal to the optical signal modification device in response to the external stimulus. ### Claim 23 (depends on 19) A sensing system as recited in claim 19, wherein the at least one sensor provides an optical signal to the optical signal modification device in response to the external stimulus. ### Claim 24 (depends on 19) A sensing system as recited in claim 19, wherein the at least one sensor provides an electromagnetic signal to the optical signal modification device in response to the external stimulus. ### Claim 25 (depends on 19) The sensor system of claim 19, wherein said external stimulus is unrelated to functional operation of said system. ### Claim 26 (depends on 25) The sensor system of claim 25, wherein said at least one sensor is selected from the group consisting of an environmental sensor and a security-type sensor. ### Claim 27 A sensing system comprising: an optical coupler for receiving at least a portion of a downstream optical signal and for providing a downstream optical sensor interrogation signal and a downstream communication information signal; a communication device for receiving the downstream communication information signal and for providing an upstream communication information signal; an optical signal modification device for receiving the downstream optical sensor interrogation signal and for modifying at least a portion of it to provide an upstream sensed signal in response to an external stimulus; and an upstream optical coupler for combining the upstream communication information signal and the upstream sensed signal to form a composite upstream optical signal. ### Claim 28 (depends on 27) A sensing system as recited in claim 27, wherein the optical signal modification device attenuates the downstream optical sensor interrogation signal in response to the external stimulus. ### Claim 29 (depends on 28) A sensing system as recited in claim 28, wherein the optical signal modification device blocks the downstream optical sensor interrogation signal in response to an external stimulus. ### Claim 30 (depends on 27) A sensing system as recited in claim 27, wherein the optical signal modification device includes a material in which a polarization of the downstream optical sensor interrogation signal passing through the material changes in response to an external stimulus. ### Claim 31 (depends on 27) A sensing system as recited in claim 27, wherein the optical signal modification device exhibits a state change and becomes responsive to the external stimulus in response to the downstream optical sensor interrogation signal. ### Claim 32 (depends on 27) The sensor system of claim 27, wherein said external stimulus is unrelated to functional operation of said system. ### Claim 33 (depends on 32) The sensor system of claim 32, wherein said at least one sensor is selected from the group consisting of an environmental sensor and a security-type sensor. ### Claim 34 An optical reporting technique comprising the steps of: receiving downstream optical signals and converting them to downstream electrical signals; providing sensor information signals from a sensor responsive to an external stimulus; receiving the downstream electrical signals and establishing communication channels to at least one communication terminal that provides communication information signals, and establishing a communication channel with the sensor; and providing the communication information signals and the sensor information signals as an upstream data signal to be impressed onto an upstream optical signal. ### Claim 35 An optical reporting technique comprising the steps of: receiving at least a portion of a downstream optical signal and providing a downstream optical sensor interrogation signal and downstream communication information signal; receiving the downstream communication information signal and providing an upstream communication information signal; providing a sensor information signal in response to an external stimulus; modifying the downstream optical sensor interrogation signal in response to the sensor information signal to provide an upstream sensed signal; and combining the upstream communication information signal and the upstream sensed signal. ### Claim 36 An optical reporting technique comprising the steps of: receiving at least a portion of a downstream optical signal and providing a downstream optical sensor interrogation signal and a downstream communication information signal; receiving the downstream communication information and providing an upstream communication information signal; receiving the downstream optical sensor interrogation signal and modifying at least a portion of it to provide an upstream sensed signal in response to an external stimulus; and combining the communication information signal and the upstream sensed signal.