# US 10,441,832 B1 · Systems and methods for building fire detection > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,441,832 B1 - Document ID: US10441832B1 - Status: Granted - Kind: B1 - Application number: 15/999,263 - Filed: 2018-08-17 - Granted: 2019-10-15 - Earliest claimed: 2018-08-17 - Assignees: Johnson Controls Technology Company - Applicants: Johnson Controls Technology Company - Inventors: Craig E. Trivelpiece; Robert C. Hall, Jr.; Timothy C. Gamroth - Web page: https://patentgrep.com/patent/US10441832B1 ## CPC - A62C 37/40: with electric connection between sensor and actuator - A62C 3/00: Fire prevention, containment or extinguishing specially adapted for particular objects or places ({in oil wells E21B29/08, A62C35/00; in mines or tunnels E21F5/00} ; for nuclear reactors G21C9/04) - A62C 3/0214: {for buildings or installations in fire storms} - A62C 99/0072: {using sprayed or atomised water} - G08B 17/06: Electric actuation of the alarm, e.g. using a thermally-operated switch - G08B 17/10: Actuation by presence of smoke or gases {, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means} - G08B 25/007: {Details of data content structure of message packets; data protocols} - G08B 25/10: using wireless transmission systems {(G08B25/009 takes precedence)} - A62C: FIRE-FIGHTING (fire-extinguishing compositions, use of chemical substances in extinguishing fires A62D1/00; spraying, applying liquids or other fluent materials to surfaces in general B05; alarm arrangements G08B, e.g. fire alarms actuated by smoke or gases G08B17/10) - G08B: SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS ## Abstract A fire detection and suppression system includes a wireless mesh network and a controller. The wireless mesh network includes of a plurality of wireless mesh nodes distributed throughout the building. The wireless mesh nodes transmit and receive wireless signals during a baseline time period and record a baseline set of signal characteristics and transmit and receive the wireless signals during a second time period after the baseline time period and record a second set of signal characteristics. The controller is configured to determine that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics as a result of a fire within the building degrading the wireless signals during the second time period. A fire is detected by the controller based on these signals and corrective action is initiated in response to detecting the fire within the building. ## Claims ### Claim 1 A method for detecting and suppressing fires in a building, the method comprising: establishing a wireless mesh network comprising a plurality of wireless mesh nodes distributed throughout the building, each of the plurality of wireless mesh nodes configured to transmit and receive wireless signals; operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during a baseline time period and recording a baseline set of signal characteristics that characterize the wireless signals during the baseline time period; operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during a second time period after the baseline time period and recording a second set of signal characteristics that characterize the wireless signals during the second time period; determining that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics as a result of a fire within the building degrading the wireless signals during the second time period; detecting the fire within the building in response to a determination that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics; and initiating corrective action in response to detecting the fire within the building. ### Claim 2 (depends on 1) The method of claim 1, wherein operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during the baseline time period and the second time period comprises operating the plurality of wireless mesh nodes within a frequency range compliant with 802.11 Wi-Fi communications specifications. ### Claim 3 (depends on 2) The method of claim 2, wherein the frequency range comprises 2.4-2.5 GHz. ### Claim 4 (depends on 1) The method of claim 1, wherein determining that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics comprises determining that the second set of signal characteristics comprise at least one of a degradation in signal strength, a degradation in link quality, or a degradation in bit rate relative to the baseline set of signal characteristics. ### Claim 5 (depends on 1) The method of claim 1, further comprising: observing the baseline set of signal characteristics and the second set of signal characteristics at each of the plurality of wireless mesh nodes; and transmitting the baseline set of signal characteristics and the second set of signal characteristics observed by each of the plurality of wireless mesh nodes to a controller. ### Claim 6 (depends on 5) The method of claim 5, wherein the controller comprises at least one of a BMS controller or a fire system controller. ### Claim 7 (depends on 1) The method of claim 1, wherein initiating the corrective action comprises activating a sprinkler system or sending an alert to emergency services. ### Claim 8 A fire detection and suppression system comprising: a wireless mesh network comprising a plurality of wireless mesh nodes distributed throughout a building, each of the plurality of wireless mesh nodes configured to: transmit and receive wireless signals during a baseline time period and record a baseline set of signal characteristics that characterize the wireless signals during the baseline time period; transmit and receive the wireless signals during a second time period after the baseline time period and record a second set of signal characteristics that characterize the wireless signals during the second time period; a controller configured to: determine that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics as a result of a fire within the building degrading the wireless signals during the second time period; detect the fire within the building in response to a determination that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics; and initiate corrective action in response to detecting the fire within the building. ### Claim 9 (depends on 8) The system of claim 8, wherein each of the plurality of wireless mesh nodes is configured to transmit and receive the wireless signals during the baseline time period and the second time period comprises operating the plurality of wireless mesh nodes within a frequency range compliant with 802.11 Wi-Fi communications specifications. ### Claim 10 (depends on 9) The system of claim 9, wherein each of the plurality of wireless mesh nodes is configured to operate within the frequency range of 2.4-2.5 GHz. ### Claim 11 (depends on 8) The system of claim 8, wherein the controller is configured to determine that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics, wherein the second set of signal characteristics comprise at least one of a degradation in signal strength, a degradation in link quality, or a degradation in bit rate relative to the baseline set of signal characteristics. ### Claim 12 (depends on 8) The system of claim 8, wherein each of the plurality of wireless mesh nodes is configured to: observe the baseline set of signal characteristics and the second set of signal characteristics; and transmit the baseline set of signal characteristics and the second set of signal characteristics to the controller. ### Claim 13 (depends on 8) The system of claim 8, wherein the controller is configured to operate as at least one of a BMS controller or a fire system controller. ### Claim 14 (depends on 8) The system of claim 8, wherein the corrective action comprises activating a sprinkler system or sending an alert to emergency services. ### Claim 15 A method for detecting fires in a building, the method comprising: establishing a wireless mesh network comprising a plurality of wireless mesh nodes distributed throughout the building, each of the plurality of wireless mesh nodes configured to transmit and receive wireless signals; operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during a baseline time period and recording a baseline set of signal characteristics that characterize the wireless signals during the baseline time period; operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during a second time period after the baseline time period and recording a second set of signal characteristics that characterize the wireless signals during the second time period; determining that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics as a result of a fire within the building degrading the wireless signals during the second time period; and detecting the fire within the building in response to a determination that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics. ### Claim 16 (depends on 15) The method of claim 15, wherein operating the plurality of wireless mesh nodes to transmit and receive the wireless signals during the baseline time period and the second time period comprises operating the plurality of wireless mesh nodes within a frequency range compliant with 802.11 Wi-Fi communications specifications. ### Claim 17 (depends on 15) The method of claim 15, wherein determining that the second set of signal characteristics are abnormal relative to the baseline set of signal characteristics comprises determining that the second set of signal characteristics comprise at least one of a degradation in signal strength, a degradation in link quality, or a degradation in bit rate relative to the baseline set of signal characteristics. ### Claim 18 (depends on 15) The method of claim 15, further comprising: observing the baseline set of signal characteristics and the second set of signal characteristics at each of the plurality of wireless mesh nodes; and transmitting the baseline set of signal characteristics and the second set of signal characteristics observed by each of the plurality of wireless mesh nodes to a controller. ### Claim 19 (depends on 18) The method of claim 18, wherein the controller comprises at least one of a BMS controller or a fire system controller. ### Claim 20 (depends on 15) The method of claim 15, further comprising initiating a corrective action in response to detecting the fire within the building, the corrective action comprising activating a sprinkler system or sending an alert to emergency services.