# US 11,998,362 B2 · Acoustic respiratory monitoring sensor having multiple sensing elements > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,998,362 B2 - Document ID: US11998362B2 - Status: Granted - Kind: B2 - Application number: 17/144,770 - Filed: 2021-01-08 - Published: 2021-05-06 - Granted: 2024-06-04 - Earliest claimed: 2009-10-15 - Assignees: Masimo Corporation - Applicants: Masimo Corporation - Inventors: Valery G. Telfort; Dimitar Dimitrov; Phi Trang - Web page: https://patentgrep.com/patent/US11998362B2 ## CPC - A61B 5/7214: {using signal cancellation, e.g. based on input of two identical physiological sensors spaced apart, or based on two signals derived from the same sensor, for different optical wavelengths} - A61B 7/003: {Detecting lung or respiration noise} - A61B 7/008: {Detecting noise of gastric tract, e.g. caused by voiding} - A61B 7/04: Electric stethoscopes - A61B 5/0006: {ECG or EEG signals} - A61B 5/0205: Simultaneously evaluating both cardiovascular conditions and different types of body conditions, e.g. heart and respiratory condition - A61B 5/02438: {with portable devices, e.g. worn by the patient} - A61B 5/02444: {Details of sensor (A61B5/02427 takes precedence)} - A61B 5/08: Measuring devices for evaluating the respiratory organs - A61B 5/0816: {Measuring devices for examining respiratory frequency (measuring frequency of electric signals G01R23/00)} - A61B 5/082: {Evaluation by breath analysis, e.g. determination of the chemical composition of exhaled breath (A61B5/083, A61B5/091 take precedence)} - A61B 5/145: Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value {; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue} (non-radiation detecting or locating of foreign bodies in blood A61B5/06) - A61B 5/4818: {Sleep apnoea} - A61B 5/6822: {Neck} - A61B 5/6833: {Adhesive patches} - A61B 5/721: {using a separate sensor to detect motion or using motion information derived from signals other than the physiological signal to be measured} - A61B 2560/0412: Low-profile patch shaped housings - A61B 2562/0204: Acoustic sensors - A61B 2562/182: Electrical shielding, e.g. using a Faraday cage - A61B 2562/222: Electrical cables or leads therefor, e.g. coaxial cables or ribbon cables - A61B 2562/227: Sensors with electrical connectors - Y10T 29/49005: Acoustic transducer - A61B: DIAGNOSIS; SURGERY; IDENTIFICATION (usefulness limited to only animals A61D) - Y10T: TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION ## Abstract According to certain described aspects, multiple acoustic sensing elements are employed in a variety of beneficial ways to provide improved physiological monitoring, among other advantages. In various embodiments, sensing elements can be advantageously employed in a single sensor package, in multiple sensor packages, and at a variety of other strategic locations in the monitoring environment. According to other aspects, to compensate for skin elasticity and attachment variability, an acoustic sensor support is provided that includes one or more pressure equalization pathways. The pathways can provide an air-flow channel from the cavity defined by the sensing elements and frame to the ambient air pressure. ## Claims ### Claim 1 An acoustic sensor system comprising: a first acoustic sensor comprising at least: a first sensing element; and a first electrode layer; and a second acoustic sensor comprising at least: a second sensing element; and a second electrode layer, wherein the first and second acoustic sensors are arranged in a stack, wherein the first and second sensing elements are positioned between the first and second electrode layers, and wherein the first and second electrode layers are configured to form an electromagnetic noise shielding barrier. ### Claim 2 (depends on 1) The acoustic sensor system of claim 1, wherein the first and second electrode layers comprise electrode coatings on the respective first and second sensing elements. ### Claim 3 (depends on 2) The acoustic sensor system of claim 2, wherein the first and second sensing elements comprise piezoelectric elements. ### Claim 4 (depends on 3) The acoustic sensor system of claim 3, wherein the first and second electrode layers are coupled to a common potential. ### Claim 5 (depends on 4) The acoustic sensor system of claim 4, wherein: the first acoustic sensor further comprises a first inner layer positioned between the first and second sensing elements, the second acoustic sensor further comprises a second inner layer positioned between the first and second sensing elements, the first inner layer covers a first percentage of an inner surface area of the first sensing element, and the first electrode layer covers a second percentage of an outer surface area of the first sensing element, the second percentage greater than the first percentage. ### Claim 6 (depends on 5) The acoustic sensor system of claim 5, wherein the second inner layer covers a third percentage of an inner surface area of the second sensing element, and wherein the second electrode layer covers a fourth percentage of an outer surface area of the second sensing element, the fourth percentage greater than the third percentage. ### Claim 7 (depends on 6) The acoustic sensor system of claim 6, wherein the first acoustic sensor produces a first signal in response to acoustic vibrations and provides the first signal to a noise attenuator, wherein the second acoustic sensor produces a second signal in response to acoustic vibrations and provides the second signal to the noise attenuator, and wherein the noise attenuator is responsive to the first and second signals to produce a reduced noise signal having a higher signal to noise ratio than either of the first or second signals. ### Claim 8 (depends on 7) The acoustic sensor system of claim 7, wherein the first and second electrode layers distribute electromagnetic noise incident on the acoustic sensor system substantially evenly between the first signal and the second signal. ### Claim 9 (depends on 8) The acoustic sensor system of claim 8, wherein the electromagnetic noise in the first signal is substantially in phase with the electromagnetic noise in the second signal. ### Claim 10 (depends on 5) The acoustic sensor system of claim 5, further comprising an intermediate layer positioned between the first and second inner layers, the intermediate layer configured electrically insulate the first and second acoustic sensors from one another. ### Claim 11 (depends on 10) The acoustic sensor system of claim 10, wherein the intermediate layer forms a substantially water resistant seal between the first and second acoustic sensors. ### Claim 12 (depends on 11) The acoustic sensor system of claim 11, wherein the intermediate layer is configured to at least partially bond the first and second sensors together such that mechanically active regions of the first and second sensing elements move together in response to acoustic vibrations. ### Claim 13 (depends on 5) The acoustic sensor system of claim 5 further comprising: a noise attenuator coupled to the first inner layer of the first acoustic sensor and the second inner layer of the second acoustic sensor, the noise attenuator configured to: at least partially constructively combine a physiological signal component of a first signal output by the first acoustic sensing element and a physiological signal component of a second signal output by the second acoustic sensing element; and at least partially destructively combine a noise component of the first signal output by the first acoustic sensing element and a noise component of the second signal output by the second acoustic sensing element. ### Claim 14 (depends on 13) The acoustic sensor system of claim 13, wherein the noise attenuator comprises at least one of: circuitry including an amplifier, a signal processor, or a general-purpose processor. ### Claim 15 (depends on 14) The acoustic sensor system of claim 14, wherein the noise attenuator is further configured to generate a reduced noise signal based on constructively combining the physiological signal components and destructively combining the noise components. ### Claim 16 (depends on 15) The acoustic sensor system of claim 15, wherein the reduced noise signal has a lower noise component than one or more of the first and second signals. ### Claim 17 (depends on 16) The acoustic sensor system of claim 16, wherein the noise attenuator generates the reduced noise signal using common-mode rejection. ### Claim 18 (depends on 1) A method comprising: receiving signals from an acoustic sensor system according to claim 1 that is attachable to a medical patient and configured to provide signals responsive to acoustic vibrations indicative of one or more physiological parameters of the medical patient. ### Claim 19 (depends on 18) The method of claim 18, wherein the acoustic sensor system further includes a coupling bump configured to apply pressure to at least one of the first and second sensing elements to push at least a portion of the one of the first and second sensing elements into a cavity of the acoustic sensor system. ### Claim 20 (depends on 19) The method of claim 19, wherein the coupling bump is configured to transmit acoustic vibrations to the one of the first and second sensing elements through the acoustic coupling bump when the acoustic sensor is attached to the medical patient.