Systems, devices, and methods for performing active auscultation and detecting acoustic energy measurements

Abstract

Active auscultation can be used to determine the characteristics of a user's organs (e.g., lungs or heart). An acoustic or piezoelectric signal (e.g., pulses, tones, and / or broadband pulses) can be projected onto the body or chest of an animal (typically a human). The signal interacts with the body or lungs and, in some cases, may cause resonance within the body / lungs. The resulting signal can be emitted from the body and analyzed to determine, for example, the resonant frequency of the lungs and / or how the sound is absorbed, reflected, or modified by the body. This information can indicate lung characteristics such as lung capacity, the amount of air trapped in the lungs, and / or the presence of COPD.

Description

[0001] This application is a divisional application of application number 201980028745.X, filing date April 26, 2019, and invention name “System, device and method for performing active auscultation and detecting sound energy measurement”. Technical Field

[0002] This application is a non-provisional application of and claims priority to U.S. Provisional Patent Application No. 62 / 663,262, filed April 27, 2018, entitled “ACTIVE AUSCULTATION DEVICE AND SONIC ENERGY MEASUREMENT SENSOR,” and is a non-provisional application of and claims priority to U.S. Provisional Patent Application No. 62 / 773,002, filed November 29, 2018, entitled “SYSTEMS, DEVICES, AND METHODS FORPERFORMING ACTIVE AUSCULTATION AND SONIC ENERGY MEASUREMENTS,” both of which are incorporated herein by reference in their entireties. Background Art

[0003] Auscultation is used to determine the condition of an animal's internal organs, typically the heart or lungs. A signal is typically introduced by manually tapping the chest or back. This signal interacts with the target organ (usually the lungs) and is detected using a stethoscope. By analyzing the detected signal, the organ's condition can be determined. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] The invention is illustrated by way of example and not limitation in the figures of the accompanying drawings in which:

[0005] Figure 1 An exemplary active auscultation system consistent with some embodiments of the present invention is shown;

[0006] Figure 2A A second exemplary active auscultation system consistent with some embodiments of the present invention is shown;

[0007] Figure 2B A third exemplary active auscultation system consistent with some embodiments of the present invention is shown;

[0008] Figure 3A Provides front and side views of a user wearing an active stethoscope system consistent with some embodiments of the present invention;

[0009] Figure 3B Provides front and side views of a user wearing a transmitter and a receiver located on opposite sides of the user's chest consistent with some embodiments of the present invention;

[0010] Figure 3C provides an illustration of an exemplary active auscultation system, consistent with some embodiments of the present invention, configured as an adhesive patch that can be attached to the epidermis of a user;

[0011] Figure 4 A block diagram of a system for acquiring and processing active auscultation data from multiple communication devices consistent with some embodiments of the present invention is provided;

[0012] Figure 5A providing an image of a scanned lung having a small amount of air trapped therein consistent with some embodiments of the present invention;

[0013] Figure 5B providing an image of a scanned lung affected by COPD including multiple pockets or volumes of trapped air consistent with some embodiments of the present invention;

[0014] Figure 6 An image is provided of an exemplary manner consistent with some embodiments of the present invention in which the left and right lungs of a user may be modeled or estimated;

[0015] Figure 7A shows a three-dimensional graph of a spectrum capture of sound that has passed through a user's lungs and has been received by a receiver, consistent with some embodiments of the present invention;

[0016] Figure 7B A graph illustrating respiratory cycle estimation consistent with some embodiments of the present invention;

[0017] Figure 8 provides a series of graphs of some exemplary sounds that may be continuously transmitted over time by a transmitter into the lungs of a user and received by an active auscultation system consistent with some embodiments of the present invention;

[0018] Figure 9 provides a graph of exemplary lung resonance signature (LRS) data consistent with some embodiments of the present invention;

[0019] Figure 10 provides a flowchart describing a process consistent with some embodiments of the present invention; and

[0020] Figure 11 Components of a computer system consistent with some embodiments of the present invention are depicted in which computer-readable instructions embodying the methods of the present invention may be stored and executed.

[0021] Throughout the drawings, unless otherwise indicated, like reference numerals and characters are used to denote like features, elements, components, or parts of the illustrated embodiments. Furthermore, although the present invention will now be described in detail with reference to the accompanying drawings, it will be described in conjunction with illustrative embodiments. It is intended that changes and modifications may be made to the described embodiments without departing from the true scope and spirit of the invention as defined by the appended claims. Summary of the Invention

[0022] The present invention actively auscultates to determine characteristics of a user's organs (e.g., lungs or heart). Sound or piezoelectric signals (e.g., pulses, tones, and / or broadband pulses) are projected onto the body or chest of an animal (typically a human). The signals interact with the body or lungs, and in some cases may induce resonance within the body / lungs. A resultant signal may be emitted from the body, which may be analyzed to determine, for example, the resonant frequency of the lungs and / or how the sound is absorbed, reflected, or modified by the body. This information may indicate characteristics of the lungs, such as lung capacity and / or the presence of COPD.

[0023] Disclosed herein is an active auscultation method that typically emits acoustic signals into a user's heart and / or lungs, typically toward a target of interest. The acoustic signals can be projected into the user's body in pulses or bursts, either continuously, periodically, and / or lasting approximately 0.1-5 seconds. In some embodiments, the acoustic signals can be broadband signals comprising multiple frequencies ranging from, for example, 2,000 Hz to 30,000 Hz.

[0024] A portion of the acoustic signal may be emitted from the user's body via, for example, backscatter or transmission, and may be received by a receiver, such as a microphone. Characteristics of the received acoustic signal may then be determined. Exemplary characteristics include the intensity, duration, and / or frequency of the received acoustic signal. The characteristics may be provided to the operator.

[0025] In some embodiments, these steps may be repeated multiple times. Features of the received sounds may be compared to one another to determine, for example, changes in the features over time and / or whether the determined features correspond to another factor, such as an improvement in the user's health, an adverse health event, weather factors, environmental factors, etc. This comparison may be provided to an operator.

[0026] Additionally or alternatively, the determined characteristic may be compared to predetermined values for that characteristic to determine, for example, how the user's characteristics compare to other characteristics to derive similarities or patterns that may be used to diagnose the user and / or predict when an adverse event may occur.

[0027] Additionally or alternatively, in some cases, the duration, intensity, and / or frequency included in the signal may be responsively adjusted in response to, for example, determined characteristics of the received acoustic signal and / or a lack of a sufficiently clear received acoustic signal.

[0028] In some cases, this characteristic can be used to determine the amount of air trapped in the user's lungs and / or the user's lung capacity.

[0029] Additionally or alternatively, in some embodiments, active auscultation can be performed by providing a signal excitation to the transmitter by a processor in communication with the transmitter, thereby causing the transmitter to generate acoustic energy at multiple frequencies that is directed to an organ of the user. The acoustic energy response corresponding to the acoustic energy at multiple frequencies directed to the organ can then be received and analyzed to determine the resonant frequency of the organ. In some embodiments, the multiple frequencies directed to the organ can include a set of discrete frequencies, predetermined frequency responses and / or frequency bins. Additionally or alternatively, the signal excitation can cause the transmitter to generate acoustic energy that cycles through the set of discrete frequencies within a predetermined time period. Additionally or alternatively, the signal excitation can cause the transmitter to generate acoustic energy that includes a series of pseudo-randomly generated and / or selected frequencies. Additionally or alternatively, the signal excitation can cause the transmitter to generate acoustic energy to produce a burst of acoustic energy that includes multiple frequencies.

[0030] In some embodiments, the amount of air trapped in the organ can be determined based on the resonant frequency of the target.

[0031] In some embodiments disclosed herein, information about a user can be received and correlated with a resonant frequency of a target and / or organ. Sometimes, the received information relates to one or more of a physiological characteristic of the user, a diagnosis of the user, a size of the organ, a shape of the organ, a type of fluid in the organ, a type of gas in the organ, a location of a transmitter, a location of a receiver, an ambient noise level, and an orientation of the user.

[0032] The exemplary systems disclosed herein may include a processor and / or server configured to provide a signal stimulus to a transmitter (e.g., a speaker) in communication with the processor, causing the transmitter to generate acoustic energy at multiple frequencies. The acoustic energy may be directed to an organ of the user's body. The processor / server may receive an acoustic energy response corresponding to the multiple frequencies of acoustic energy directed to the organ. The processor / server may then generate a comparison between the acoustic energy response and a predetermined threshold value, and then determine one or more resonant frequencies of the organ based on the comparison.

[0033] Additionally or alternatively, active auscultation may be performed by a processor in communication with the transmitter providing a first signal excitation to the transmitter, causing the transmitter to generate acoustic energy of a first plurality of frequencies directed toward the organ, the processor receiving a first acoustic energy response via a receiver in communication with the processor, the first acoustic energy response corresponding to the acoustic energy of the first plurality of frequencies directed toward the organ, the processor providing a second signal excitation to the transmitter, causing the transmitter to generate acoustic energy of a second plurality of frequencies directed toward the organ, the processor receiving a second acoustic energy response via the receiver, the second acoustic energy response corresponding to the acoustic energy of the second plurality of frequencies directed toward the organ, the processor generating a comparison between the first acoustic energy response and the second acoustic energy response, and the processor determining one or more characteristics of the organ based on the generated comparison.

[0034] In some embodiments, a wearable stethoscope sensor as used herein may include: a transmitter configured to project an acoustic signal into a user's body; a receiver configured to receive the acoustic signal emitted from the user's body; and a noise cancellation device configured to reduce ambient noise in the received acoustic signal. The noise cancellation device may be mechanical and / or electronic / acoustic in nature. In some cases, the noise cancellation device may include noise cancellation circuitry specifically designed to cancel unwanted ambient noise of known and / or unknown frequencies. In some embodiments, the noise cancellation device may analyze the ambient noise and add a signal 180 degrees out of phase with the ambient noise to the received signal to filter out the ambient noise from the received signal. DETAILED DESCRIPTION

[0035] Acoustic resonance is defined as a system (e.g., a physical object) that amplifies sound waves at a frequency that matches one or more of the system's natural vibrational frequencies. Once an object is excited with energy at a frequency unrelated to its natural vibrational frequencies, the energy dissipates rapidly. However, when the excitation approaches one of the object's natural vibrational frequencies, the object begins to resonate and vibrate strongly at that frequency. The object's resonant frequency can be excited using a specific frequency, a set of frequencies, a broadband signal (e.g., noise composed of many frequencies), a pseudo-randomly generated frequency or frequency range, a linear frequency modulation signal, and / or a white noise signal.

[0036] Systems, devices, and methods for performing active auscultation and acoustic energy measurement using resonance are described herein. The systems, devices, and methods can use active acoustic sensors, digital signal processing, and machine learning to perform continuous, long-term, and non-invasive lung health monitoring. Exemplary systems and devices include a sound or acoustic energy transducer / transmitter (e.g., a speaker) and an acoustic energy transducer / receiver (e.g., a microphone). Typically, the transmitter can be configured to emit a range of sounds (e.g., 20 Hz to 100 kHz) that will pass through the user's skin and penetrate a part of their body (e.g., chest or thorax), and the receiver can be configured to receive sounds within this range.

[0037] Lung function assessment, as well as COPD diagnosis and monitoring, is typically performed using various functional tests (e.g., spirometry, plethysmography), imaging techniques (e.g., CAT scans, X-rays), and a physician’s observation and examination. These techniques require specialized equipment and must typically be performed in a medical setting and administered by a medical professional. Spirometry and other tests require the user to stop all activity and breathe into the device in a certain manner. This makes continuous lung function monitoring cumbersome, significantly impacting the user’s daily routine and making home care difficult.

[0038] The systems, devices, and methods disclosed herein can be used to measure acoustic resonance in a user's body or a portion thereof (e.g., an organ such as the lungs or heart). The measured resonance characteristics may be affected by, for example, air, fluid, or fat contained within the user's body or the target tissue and / or other physiological characteristics that may respond to acoustic stimulation.

[0039] In one embodiment, the measured resonance can be used to detect and / or determine the severity of air trapped in the user's lungs. Air may be trapped in the user's lungs due to the user's respiratory condition (e.g., chronic obstructive pulmonary disease (COPD) or asthma). Additionally or alternatively, the measured resonance characteristics can be used to monitor changes in air in the lungs during the respiratory cycle (i.e., inhalation and exhalation) and can be used to compare one area of the body to another (e.g., one lung to another).

[0040] In some embodiments, the present invention can be used to track lung function over time, for example, to establish a baseline of lung function and monitor changes from that baseline as a way to monitor lung health. This can be helpful in determining whether a user may be susceptible to an infection or adverse event (e.g., an asthma attack) so that preventative measures and / or treatment can be taken.

[0041] The transmitter and receiver can be housed in the same or separate housings. The housing can facilitate the projection of acoustic energy to a target location within the user's body via the transmitter and / or facilitate the detection of sound emitted from the user's body via the receiver. For example, the shape or features of the housing can direct the acoustic energy toward a target and / or facilitate the detection of sound emitted from the user's body.

[0042] The housing can be configured to be positioned adjacent to the user's skin. Such positioning can reduce the introduction of noise (e.g., ambient noise, crosstalk, etc.) into the signal received by the receiver because, for example, the noise may not be able to enter the receiver through the gap or space between the housing and the user's skin. Additionally or alternatively, the exemplary housing can include one or more mechanical and / or electronic noise reduction mechanisms to prevent the receiver from detecting ambient sounds.

[0043] In some embodiments, the housing can include multiple transmitters and / or receivers. Additionally or alternatively, the system can include multiple transmitters and / or receivers, each within its own housing, which can be configured to be placed at various locations of the user, for example.

[0044] The systems, devices, and methods disclosed herein have the potential to standardize a portion of the auscultation routine by eliminating the need for the user to generate sounds by, for example, coughing, sneezing, or breathing to produce sounds in the lungs.

[0045] Turning now to the accompanying drawings, Figure 1 An exemplary active auscultation system 100 is shown, comprising an exemplary housing 105 for a transmitter 110, a receiver 115, a processor / memory 160 communicatively coupled to the transmitter 110 and the receiver 115, and an optional mechanical noise reduction mechanism 150. In some cases, the active auscultation system 100 may also include a transceiver by which it can communicate with an external electronic device (e.g., a computer or smartphone) (not shown) via, for example, a wireless communication protocol. The transmitter 110 can be any device that transmits and / or is capable of generating sounds, vibrations, waves, and / or pulses. Exemplary transmitters 110 include, but are not limited to, speakers, vibrators, piezoelectric transducers, electromechanical transducers, or any other device capable of converting an electrical signal into an audio waveform by, for example, exciting the surrounding air and / or surrounding medium (e.g., skin, water, and / or subcutaneous fat).

[0046] like Figure 1 As shown, the transmitter 110 and / or receiver 115 can be positioned within the housing 105 so that they can be positioned near the surface of the user's skin 130. In some cases, the transmitter 110 and / or housing 105 can be positioned on the user's body so that sound can be transmitted to the skin layer 130 and directed to a target within the body 135, such as, but not limited to, organs like the lungs or heart. Typically, the housing 110 will be positioned on the user's chest to facilitate transmission of sound energy to the chest cavity.

[0047] In some embodiments, the housing 105 can be configured to allow movement over the user, such as by sliding along a strap or manually moving by an operator (e.g., a physician), to analyze acoustic energy reflected and / or emitted by the user. The mechanical noise reduction mechanism 150 can be any material configured to mechanically prevent ambient noise from reaching the receiver 115, including foam, fiber, or other material that absorbs sound. In some embodiments, the mechanical noise reduction mechanism 150 surrounds the perimeter of the housing 105 and can be positioned to coincide with the user's skin 130. Although in Figure 1105 , but in some embodiments, the mechanical noise reduction mechanism 150 can extend over and cover a portion or all of the housing 105. Additionally or alternatively, the mechanical noise reduction mechanism 150 can extend beneath the housing 105 (not shown) to form a noise reducing interface between the housing 105 and the user's skin 130. Additionally or alternatively, the mechanical noise reduction mechanism 150 can reside within the housing 105 (not shown), for example, as a noise reducing foam or fiber that occupies space within the housing that is not occupied by components of the active stethoscope system 100. Additionally or alternatively, the mechanical noise reduction mechanism can be a lining 155 located on the interior and / or exterior of the housing 105.

[0048] The processor / memory 160 may be configured to execute one or more instructions that may be stored in the memory. For example, the processor / memory 160 may provide a signal stimulus to the transmitter 110 that causes the transmitter to generate acoustic energy of one or more frequencies (also referred to herein as a source signal). The source signal Figure 1 13. The target area of the subject 135 is shown as a first dashed line 120 which passes through the skin layer 130 and into the target area of the subject 135. In some cases, the transmitter 110 may be provided with a broadband signal excitation or other signal utilizing multiple frequencies such that the source signal has multiple frequencies. The source signal may provide these multiple frequencies simultaneously (i.e., the source signal includes multiple frequencies at a time) and / or the source signal may include multiple frequencies in succession, each frequency being projected by the transmitter at a different time. The processor / memory may also store and / or cache received signals for later transmission to a communication device such as the communication device 310, as will be described below with respect to Figures 3A-3C discussed.

[0049] In some embodiments, the processor / memory 160 may adjust the signal excitation based on one or more factors, which may include, but are not limited to, physiological factors of the user (e.g., gender, body mass index, age, etc.), the user's diagnosis, the size and / or shape of the target, the type of fluid or gas that may be present in the body or target 135, the location of the sensor, the level of ambient noise, the orientation of the user (e.g., vertical or horizontal), and the like.

[0050] In some cases, the stimulus may coincide with or be similar to one or more naturally occurring frequencies of the target (e.g., a target organ) that may be caused by, for example, rhythmic movement (e.g., breathing or heartbeat) and / or frequencies occurring in the surrounding environment (e.g., fan noise, equipment noise). In these embodiments, the stimulus may be adjusted so that the target's response to the stimulus can be more easily distinguished from these frequencies.

[0051] In some embodiments, the transmitters 110 can simultaneously generate mutually orthogonal signals (e.g., pseudorandom noise with different keys). When these mutually orthogonal signals are received, they can then be used to decorrelate the strengths of return signals at different frequencies. Additionally or alternatively, the source signal can be transmitted across multiple transmitters 110 located at multiple locations of the user using time division.

[0052] Then, the receiver receives the acoustic energy signal emitted from the user's body by, for example, reflection or resonance. The received acoustic energy signal is Figure 1 125. This received acoustic energy 125 (also referred to herein as a return signal) may be received by a processor / memory 160, which may determine characteristics of the sound, such as frequency and / or intensity, over time. Exemplary characteristics include the intensity level of each frequency, the overall intensity of a frequency or frequency range over time, and / or the intensity distribution within a frequency range over time.

[0053] In some cases, source signal can comprise multiple frequencies, can be referred to as broadband signal and / or white noise signal in this article.In some cases, frequency and / or the white noise included in multiple frequencies can be selected pseudo-randomly.For example, signal excitation can make transmitter 110 transmit broadband or white noise source signal, and this broadband or white noise source signal can be configured to provide return signal, and this return signal can have flat and / or known frequency response on average in some or all frequency bins (bin).Frequency bin is the subset of frequency range within the frequency range of source signal.For example, if the frequency that source signal provides is in the scope of 1-100kHz, then frequency segment can be arranged on the scope within this frequency range with given increment (for example 5,10,15,20,kHz etc.).

[0054] In some embodiments, using white noise in the source signal and / or using white noise as the source signal and / or using different types of white noise (e.g., white noise with different frequency range characteristics) can help estimate the characteristics of the return signal (e.g., strength, propagation time, scattering, etc.). In addition, for embodiments using two transmitters (typically, each transmitter is placed at a different location, such as on the left and right sides of the user's chest so that the sound can be projected to each lung of the user), each transmitter can use a white noise signal with a different set of frequencies (which can be randomly or pseudo-randomly selected), so that when one or more receivers (such as receiver 115) detect and / or receive the first white noise signal, it can be distinguished from the other white noise. Sometimes, analysis of the detected signals may yield information about crosstalk or leakage of the source signal from one location to another.

[0055] In addition or alternatively, by for example increasing and / or reducing the frequency of the source signal in a periodic manner (for example, with a sinusoidal form) over time, the source signal can be set to circulate in a group of frequencies, and / or the source signal can be a group of frequencies that are for example raised or reduced in a periodic, random, pseudo-random or patterned manner. This type of source signal can be referred to as a linear frequency modulation signal. The frequency response of the user and / or target to this linear frequency modulation signal can be estimated by measuring the response signal and integrating this signal over time.

[0056] Additionally or alternatively, a pseudo-randomly generated frequency or frequency range can be used to generate the source signal. This can be a targeted or narrow frequency range or a broadband frequency range. The linear frequency chirp source signal can accurately measure the resonance response of the user's chest and / or lungs. In some cases, multiple measurements of the user can be made using multiple linear frequency chirp source signals to, for example, determine the average minimum and / or maximum amplitude and / or intensity values of the user's response to the linear frequency chirp source signal.

[0057] Additionally or alternatively, the source signal may be a brief but powerful / intense burst of acoustic energy. The return signal may then be analyzed to determine the frequency response to the burst source signal. One advantage of using pulses is that they can be measured quickly.

[0058] Typically, an acoustic pulse (i.e., a source signal of short duration) may be used not only to measure the frequency response of the user and / or target, but also to determine the time to target (echo) for the purpose of localization or positioning of the active auscultation system 100 and / or its components. Additionally or alternatively, the acoustic pulse may help identify and characterize crosstalk or leakage between multiple speaker / microphone sensors located on the user.

[0059] Figure 2A A second exemplary active auscultation system 200 is shown in communication with the user's skin 130, the system including an active or electro-acoustic noise reduction system. The second exemplary active auscultation system 200 includes a housing 205 housing the transmitter 110, a receiver 115, a processor / memory 160, an optional mechanical noise reduction mechanism 150, an optional lining 155, and an active / electro-acoustic noise reduction system 210. The active / electro-acoustic noise reduction system 210 can be, for example, a receiver oriented away from the user and / or transmitter 110 and can be configured to capture ambient noise and / or environmental sounds. The sound receiving active / electro-acoustic noise reduction system 210 can be used, for example, to filter the received acoustic signal 125 to remove sounds that are not emanating from the user and / or target 135 and that may be considered noise. The mechanical noise reduction mechanism 150 can be implemented with the housing 205 in a manner similar to that of the housing 205.

[0060] Figure 2BA third exemplary active auscultation system 201 is shown that communicates with the user's skin and includes multiple receivers and an optional active or electro-acoustic noise reduction system. The third exemplary active auscultation system 201 includes a housing 205 that houses a transmitter 110, a processor / memory 160, an optional mechanical noise reduction mechanism 150, an optional lining 155, an optional active / electro-acoustic noise reduction system 210, and multiple receivers 115A, 115B, and 115C. The multiple receivers 115A, 115B, and 115C can be arranged in an array and can be configured to receive acoustic energy signals 125A, 125B, and / or 125C, respectively. By, for example, the following description of Figures 3A-3C and Figure 4 The discussed processor / memory 160 and / or a processor / computer not residing within the housing, such as the communication device 310 and / or the server 420, may be used to digitally process one of the received acoustic energy signals 125A, 125B, and / or 125C, for example, by beamforming and / or eliminating portions of the signal received from undesirable directions (e.g., a target location not within the user's body) and / or focusing on portions of the received acoustic energy signal 125A, 125B, and / or 125C from a point of interest.

[0061] Figure 3A A front view and a side view of a user wearing the active stethoscope system 100, 200, or 201 are provided. The active stethoscope system 100, 200, or 201 is connected to the user via a mounting device (e.g., a belt or strap) 205 that surrounds the user's torso and body. The active stethoscope system 100, 200, or 201 is maintained in position, typically flush with the user's skin. The mounting device 205 can be configured to maintain the position of the active stethoscope system 100, 200, or 201 over time as the user wears the active stethoscope system 100, 200, or 201. Figure 3A Also shown is an external communication device 310 that communicates with the active auscultation system 100, 200, or 201 via the BLUETOOTH™ wireless communication protocol. The communication device 310 can receive signals and / or send signals to the active auscultation system 100, 200, or 201 and can process those signals according to one or more methods disclosed herein.

[0062] Figure 3B A front view and a side view of a transmitter 110 and a receiver 115 worn by a user are provided, with the transmitter 110 and the receiver 115 located on opposite sides of the user's chest. The receiver 115 and / or the transmitter 110 can communicate with the communication device 310, and in some cases, their respective activities can be controlled and monitored by the communication device 310.

[0063] Figure 3CSchematic diagrams of exemplary active auscultation systems 100, 200, and / or 201 are provided, which are configured as adhesive patches that can be attached to the skin of a user. Figure 3C A side view of the user is also provided, illustrating where the active stethoscope system 100, 200, and / or 201, embodied as an adhesive patch, may be secured to the user's chest. Figure 3C A front view of the user is further shown, with two active auscultation systems 100, 200, and / or 201 located on the left and right sides of the user's chest. The active auscultation systems 100, 200, and / or 201 can communicate with the communication device 310 by wire and / or wireless communication, and in some cases, their respective activities can be controlled and monitored by the communication device 310.

[0064] The housings, transmitters, receivers and / or systems disclosed herein may be configured for single use (eg, may be disposable) or for multiple use.

[0065] Figure 4 A block diagram is provided of a system 400 for acquiring and processing active auscultation data from a plurality of communication devices 310, each in communication with one or more active auscultation systems 100, 200, and / or 201. The system 400 may include a plurality (e.g., 100, 1000, 1,000,000, etc.) of communication devices that communicate with each other. Figure 4 4. The system 400 is depicted as communication devices 310A, 310B, 310C, and 310N. Communication devices 310A, 310B, 310C, and 310N are communicatively coupled to a server 420 via a communication network (e.g., the Internet) and / or a remote server 410A. Server 420 is communicatively coupled to a first database 415 and a second database 430. Optionally, system 400 may include a private access terminal 455 and / or a public access terminal 445, either or both of which may be communicatively coupled to database server 415 and / or database 430 via a communication network (e.g., the Internet) and / or a remote server 410B. In some embodiments, communication network / remote server 410A and communication network / remote server 410B may be the same and / or may be communicatively coupled to each other. Components of system 400 may be communicatively coupled to each other via wired and / or wireless communication links.

[0066] The communication devices 310A-310N can receive raw and / or processed data (e.g., data from which noise has been removed, data from which one or more features have been extracted, etc.) from one or more active auscultation systems, such as the active auscultation system 100, 200, and / or 201 that is being / has been worn by one of a plurality of corresponding users. The data can be received in real time and / or can be buffered on the corresponding active auscultation system until it is within communication range with the communication device 310. In some embodiments, each communication device 310A-310N can add personal identification information and / or an anonymous identifier (e.g., a string of numbers or letters used to anonymously identify the user) to the data it communicates with the server 420 in order to associate the received data with the user and / or the user's anonymous identity.

[0067] In some embodiments, one or more communication devices 310 may store data thereon short-term and / or long-term, for example, for purposes of providing feedback and / or measurement to users of the respective communication devices 310. Additionally or alternatively, one or more communication devices 310 may analyze and / or process the raw data prior to communicating it to the server 420 by, for example, applying filters, noise reduction techniques, amplification techniques, etc.

[0068] Additionally or alternatively, one or more communication devices 310 may tag or associate a flag with data indicating a particular condition, for example, to transmit the particular data to the user, the user's healthcare provider, and / or researchers. Data that may be of particular interest includes data received in connection with the timing of adverse events (e.g., coughing episodes, infection episodes, hospitalizations, etc.) and / or events of interest (e.g., when the user is at rest, while exercising, etc.).

[0069] Additionally or alternatively, data entered by the user and / or other auxiliary data may be provided to the server 420 via one or more communication devices 310A-310N. The user input and / or auxiliary data includes, but is not limited to, the user's heart rate, the user's body temperature, the user's demographic information (e.g., race, gender, age, etc.), an activity performed by the user at the time the data is collected (e.g., light exercise, vigorous exercise, resting), medical diagnosis information, and medical history information. The data may be entered by the user and / or the user's caregiver via a user interface such as a keyboard and / or speech-to-text recognition. In some cases, the auxiliary data may be tagged and / or time-stamped to correlate with the received acoustic signal.

[0070] The server 420 may receive data (e.g., raw, processed, and / or auxiliary) from the plurality of communication devices 310 and prepare user data 435 for storage in the database 415. The user data 435 may include, but is not limited to, received raw and / or processed acoustic signals and auxiliary data of the user and / or correlations between the auxiliary data and the received raw and / or processed acoustic signals, which may be indexed and / or placed in a lookup table stored in the database 420 by the server 420.

[0071] In some embodiments, user data 435 may be anonymized and / or aggregated 425 and stored in database 430. The process of preparing user data 435 may be consistent with any requirements for data privacy imposed by regulatory agencies, users, and / or healthcare institutions or administrators.

[0072] User data 435 and / or anonymized / aggregated data 425 may be used to develop a model 440 that correlates data derived using active auscultation systems 100, 200, and / or 201 (e.g., lung resonance data and / or received acoustic signals) with auxiliary and other data, such as medical laboratory data, imaging data (e.g., CT scan data, MRI scan data), medical history, geographic data, pollution levels corresponding to a geographic location, weather, temperature, humidity, activity measured by sensors (e.g., accelerometers), and / or user-entered advertising library data via text, email, voice commands, etc. In some cases, a model may be developed for a single user, for example, to monitor the user's health status and / or predict changes in the user's health status and / or adverse events for the user. Additionally or alternatively, a model may be developed for a group of users sharing common characteristics (e.g., disease progression level, age, oxygen consumption rate, geographic location, altitude, disease stage, occupation, etc.). Additionally or alternatively, a model may be developed for all users aggregated together.

[0073] Exemplary uses of model 440 include, but are not limited to, event classification, anomaly detection, unexpected event detection, event prediction, determination of appropriate intervention, and the like.

[0074] Those who have access to user data 435 and / or model 440 (e.g., doctors, caregivers, etc.) can do so through communications (e.g., requests and responses to requests) between server 420 and server 420 via communication network / remote server 410B via dedicated access terminal 455. In some embodiments, permissions to use the private access terminal can be limited to those permissions granted by the user and / or healthcare provider associated with the particular user's data stored in database 415.

[0075] A user of the public access terminal 445 may not have permission to view personally identifiable information associated with one or more users and, therefore, may only access anonymous and / or aggregated user data 425 and / or model 440, as may be stored in a database 430, through communications between the public access terminal 445 and the server 420, which may facilitate communications via the communication network / remote server 410B.

[0076] The system 400 can be used to aggregate data from multiple users and / or communication devices 310, and the data can be used, for example, using machine learning or other processes to identify commonalities and / or trends within the data that can be used to diagnose and / or monitor lung conditions and / or the health of the user. Additionally or alternatively, the aggregated data from multiple users can be used to learn trends in air entrapment or other respiratory issues, which can be used to predict adverse events or other complications for the user. Additionally or alternatively, the aggregated data from multiple users can be used to generate and / or use large-scale transaction models that can be used, for example, to monitor other respiratory disorders in users diagnosed with COPD.

[0077] Figure 5A An image 501 of a scanned, relatively healthy lung is provided, with small amounts of air trapped therein, which appear as black spots in the image 501 . Figure 5B An image 502 of a scanned lung affected by COPD is provided, which includes a plurality of pockets or volumes of trapped air, which are shown as a plurality of black dots in the image 502 .

[0078] Figure 6 An image 600 is provided in an exemplary manner in which a user's left lung 605A and right lung 605B may be modeled or approximated with a tube 610 having one or two open ends (which may represent bronchial airways) and a circle 615 (which may represent a spherical or nearly spherical trapped air). Figure 6 The model shown in may be based on images such as images 501 and / or 502 showing pockets of trapped air and / or received acoustic signals.

[0079] Tables 1 and 2 below provide exemplary data that can be used to build a user's lung model with approximate bronchial tubes and trapped air pockets. In some cases, this data can be used to establish one or more relative measurements of trapped air volume and / or a set of measurements / determinations that may be unique (or specific) to a particular user, depending on (for example) the user's lung characteristics (e.g., airway size, lung size, and trapped air volume), which in some cases can be used as a benchmark against which subsequent measurements can be compared. In some cases, these measurements / determinations can be considered a score or lung health score.

[0080] The length and diameter of the lung airways vary from primary to secondary, generally decreasing in size with each branch, as shown in Table 2. The airway shape approximates a tube with one or both ends closed. Although the airways are connected, the change in diameter changes the impedance to sound / acoustic energy and, at many frequencies, behaves like a tube with one end closed. The expected frequency for a tube with one or both ends closed can be determined to obtain a range of diameter estimates. The resonant frequency of each airway can be calculated using Equation 1:

[0081]

[0082] Where v is the speed of sound, L is the length of the tube closed at one end, and d is the diameter of the tube closed at one end (for a tube closed at both ends, d = 0). The speed of sound in air at 20°C is 343 m / s. The speed of sound in air at 37°C (the temperature of a person passing through it) can be estimated using Equation 2:

[0083] v = 331.4 + 0.6Tc Formula 2

[0084] Where Tc is the temperature in Celsius. The speed of sound in air at 37°C is 353.6 m / s.

[0085] In one example, the resonant frequencies of the right aorta (fr) and the left aorta (fl), which have two closed ends, and the left and right lungs, can be determined by entering the following values into Equation 1:

[0086] v=353.6m / s

[0087] Right lung L = 0.025 m

[0088] Left lung L = 0.05 m

[0089] Right lung d = 0.014 m

[0090] Left lung d = 0.010 m

[0091]

[0092] Table 1: Estimated expected resonant frequencies for airways in the left and right bronchi. Following a similar process, all other airways can be calculated, as shown in Table 2.

[0093]

[0094] Table 2: Estimated airway resonance

[0095] The values in Table 2 can model the interaction of the lungs (or lung airways) with sound, thereby approximating, for example, the expected resonant acoustic frequency range of a lung airway in the form of a tube. A closed tube can be a model of a large tube that can be inserted into a smaller tube (e.g., a narrowed airway), where the narrowing behaves like a wall from the perspective of the air. The model in Table 2 can help select an appropriate frequency range to infuse into the lungs and / or narrow the analysis of detected sounds by selectively focusing on frequencies most likely corresponding to a specific user's lung anatomy / airway size.

[0096] Trapped air can be understood as air that is trapped in the lungs after exhalation, and determining how much air is trapped in the user's lungs may be useful for COPD prognosis. The size and distribution of the trapped air volume can be in the range of, for example, 1 to 5 mm in diameter, and the volume can be modeled and / or approximated as a sphere with a small circular opening (ventilated sphere). Sometimes, the contents of this volume / sphere of trapped air may be carbon dioxide that is depleted of oxygen in the air, and the content of carbon dioxide is higher than that of the surrounding air. The speed of sound in carbon dioxide is 259 m / s (lower than the speed of sound in air). In one example, a speed of sound between the air speed and the carbon dioxide speed (e.g., 300 m / s) can be used.

[0097] The resonant frequency of the vented sphere is given by Equation 3:

[0098]

[0099] in:

[0100] v = speed of sound in the gas

[0101] D = diameter of the sphere, and

[0102] d = opening diameter

[0103] The resonant frequencies for different exemplary sizes of trapped air volumes have been calculated using Equation 3, with v = 300 m / s, and are provided in Table 3 below.

[0104] Diameter of sphere (mm) Diameter opening (mm) Resonance frequency (Hz) 10 2.5 25370Hz 20 5.0 12685Hz 30 7.5 8457Hz 40 10 6342Hz 50 12.5 5074Hz

[0105] Table 3: Estimated resonance of trapped air volume

[0106] The values of Table 3 can be used to model the interaction of trapped air with sound by approximating the trapped air volume of a spherical bubble, thus establishing a baseline for the resonant frequencies that can be expected for the model air volume of trapped air.

[0107] The simplified lung models of Tables 1-3 can indicate acoustic resonances in the frequency range of 1.6 KHz to 30 KHz, thereby providing an indication of the frequency range that is most likely to resonate within the lungs, which corresponds to the target frequencies to be projected into the lungs or otherwise tracked to determine the user's lung resonance. For each individual lung or group of lungs, the specific resonance measured will be different depending on its actual lung characteristics (including but not limited to airway size, amount of trapped air, etc.). The resonance measured for each person can be referred to as a lung resonance signal (LRS). The LRS of each user may change over time, and tracking these changes may help monitor or diagnose lung health and / or disease progression. In some embodiments, instantaneous or rapid changes in the LRS help establish a respiratory cycle.

[0108] The values of Table 2 and / or Table 3 can be used to model the expected resonant frequency range in healthy human lungs and / or the lungs of people with COPD. These values can be used to determine a set of frequencies that resonate with the lungs of a specific user. Because the lung anatomy (e.g., the shape, length, diameter, etc. of the bronchi) is highly individual-specific, the resonant frequencies of the lungs of each individual user may vary from one individual to another. Once a user's resonant frequency baseline is established, it can be used to track changes over time. These changes may indicate changes in lung disease, the development of pathology, and / or a worsening of the disease that may indicate an impending serious event (possibly requiring hospitalization).

[0109] In some embodiments, the resonant frequencies of multiple users can be determined and aggregated to find resonant patterns across the lungs and / or trapped air of multiple users. This can be used for monitoring and / or prognostic purposes, such as to diagnose COPD and / or determine the severity of a user's COPD condition.

[0110] Figure 7A A three-dimensional graph 701 of a spectrum capture of sounds that have passed through the user's lungs and have been received by a receiver via an active auscultation system, such as active auscultation systems 100, 200, and / or 201, is shown, with amplitude on the Z axis, time on the X axis, and frequency on the Y axis. The spectrum capture displays the peak amplitudes of the resonant regions at different time periods as points. Figure 7B Also shown is a graph of respiratory period estimate 702, which plots the maximum amplitude from graph 701 as a function of time in seconds.

[0111] Figure 8A series of graphs 800 are provided of some exemplary sounds that may be emitted continuously over time by a transmitter (e.g., transmitter 110), projected onto a user's lungs, and received by an active auscultation system (e.g., active auscultation systems 100, 200, and / or 201) via a receiver (e.g., receiver 115). The original received sound is shown as a waveform on a first graph 810, with its intensity / power in decibels (dB) plotted over time in seconds on the X-axis and in dB on the Y-axis. As shown in graph 810, the intensity of the received sound decreases as the user inhales and increases as the user exhales. Figure 8 The second graph 815 shows the frequency spectrum variation in Hz, which varies over time and corresponds in time to the values of the first graph 810 . Figure 8 Also shown is a third graph 820 that provides the user with the user's respective estimated breathing cycles or total changes in air volume corresponding in time to the values of the first graph 810 and the second graph 815 .

[0112] Figure 9 A graph 900 of exemplary lung resonance signature (LRS) data for a user is provided, showing frequency in Hz as a function of intensity or power in dB. Graph 900 provides a first line 910 illustrating a range of frequencies and intensities for a lung with trapped air and a second line 915 illustrating a range of frequencies and intensities for a lung without trapped air.

[0113] The sounds detected by one or more detectors in communication with a user can be used in a variety of ways to infer the physiological condition of a patient or user. For example, the detected sounds can be analyzed to determine the spectral shape of the sounds, which can be understood as the relative or absolute relationship between the detected frequency ranges. In addition to the spectral shape, the spectral tilt can be determined by analyzing the received sounds to determine whether the energy and / or intensity of the detected frequencies increases and / or decreases with frequency, and / or to determine whether any peaks or valleys occur in the intensity / energy of the detected sounds at specific frequencies or frequency ranges. In some cases, the spectral shape of the detected sounds can include information about how many peaks and / or valleys there are in the intensity / power of the detected sounds across the entire frequency range, as well as any other features, such as the slope of the shape, areas of maximum energy, areas of minimum energy.

[0114] The spectral shape of the detected sound can be measured and / or determined instantaneously, periodically, and / or as needed, and in some cases, multiple spectral shape measurements / determinations can be made over time so that the user's response to the input sound can be monitored, for example, to determine changes and / or rates of change. This may be helpful in tracking rapid or slow improvements or declines in the user's condition.

[0115] In some cases, the detected sound may also be analyzed to determine the spectral centroid (also known as the "center of mass") of the spectrum of the detected / received sound / acoustic energy. In some cases, the spectral centroid may be calculated as a weighted average of the frequencies present in the detected / received sound. In some cases, this calculation may be performed using a Fourier transform, where the magnitude of a particular frequency is shown as follows:

[0116] The weight in formula 4:

[0117]

[0118] in:

[0119] x(n) = weighted frequency value or amplitude of bin number n;

[0120] and

[0121] f(n) = center frequency of the bin.

[0122] The spectral centroid may be tracked over time to monitor, for example, the range of frequencies detected and / or received by an active auscultation system, such as active auscultation systems 100 , 200 , and / or 201 .

[0123] Additionally or alternatively, the harmonics and / or harmonic variations of the detected sound can be analyzed to determine the spectral characteristics of the detected sound. This analysis can reveal portions of the detected signal with higher and / or lower power / intensity (i.e., peaks and / or valleys in the intensity or power of the detected sound, respectively) and / or the relationship between different frequencies within the detected sound. Sometimes, the relationship between these different frequencies may be simple and exhibit regular patterns (e.g., harmonics). Additionally or alternatively, the spacing between bumps, changes in spacing, the relative amplitudes of the detected sound / acoustic energy, etc. can be analyzed and monitored over time to determine changes or patterns that may be diagnostically significant.

[0124] For COPD-specific embodiments, the present invention can be used to monitor a user's lung function and health by measuring or otherwise assessing the amount of air trapped in the user's lungs after complete exhalation (i.e., trapped air volume), which can serve as an indicator of COPD prognosis and lung health for users diagnosed with COPD. In one embodiment, the acoustic resonance of one or more lungs of a user can be measured and / or determined and / or modeled based on one or more parameters described herein.

[0125] In some embodiments, a pair of transmitters and receivers are configured for use with the user's left and right lungs (i.e., one transmitter and one receiver for each lung). This embodiment can be used with a stereo sound card for playback and capture. The signals received by the receivers can be analyzed, for example, by measuring the amount and frequency characteristics of the excitation from one channel to another to detect and / or characterize cross-channel leakage (e.g., sound projected from the left lung is received by the receiver in the right lung). It is contemplated that "orthogonal" excitation can be used for the two channels (i.e., sound is projected into both lungs). This can minimize cross-interference between the channels (e.g., using a varying pseudo-random sequence or time division to measure each channel at a different time).

[0126] In some cases, when using a pair of transmitters and receivers, an excitation can be provided to the first transmitter in the left lung, and the second lung's receiver can be used to determine how much cross-channel leakage is detected. This process can be reversed to see if the sound projected into the second lung at the first lung's receiver indicates cross-channel leakage. If cross-channel leakage is detected, an orthogonal noise-like signal can be created and used as the excitation for one or both transmitters. Cross-channel leakage can then be measured by providing a signal to both lungs and measuring the detected sound using both detectors simultaneously. Knowledge of the pseudo-random sequence used to generate the sound can be used to infer the contribution of each channel received at the detector. This can be used to remove the estimated leakage contribution from the detected signal.

[0127] Figure 10 A flowchart is provided illustrating a process 1000 for determining a correlation between characteristics of an acoustic signal received by an active auscultation system, such as active auscultation systems 100, 200, and / or 201, and auxiliary information of a user from whom the acoustic signal was received. Process 1000 can be performed by any system and / or system component disclosed herein.

[0128] Initially, in step 1005, one or more acoustic signals emitted from a user may be received by a processor, such as processor / memory 160, and / or a server, such as server 420, for example, from a receiver, such as receiver 115, and / or an active auscultation system, such as active auscultation 100, 200, and / or 201. Auxiliary information may then be received in step 1010. Auxiliary information, such as the auxiliary information described above, may be received in step 1010. Exemplary auxiliary information includes, but is not limited to, information received from the user (e.g., medical information, onset of medical complications or emergencies, mental health status information, etc.) through interaction with a communication device, such as communication device 310, and / or information received directly from the communication device. Auxiliary information received directly from the communication device may include geographic information, altitude, local weather information, local air quality information, and the like. Additionally or alternatively, the auxiliary information may include information captured by a software application running on the communication device. Exemplary software applications may collect information related to, for example, the user's activity level, the user's heart rate, and the user's blood oxygen saturation.

[0129] In step 1015, one or more characteristics of the acoustic signal may be determined and / or received. The determined characteristics may include any of the characteristics described herein. In step 1020, one or more correlations between the characteristics of the acoustic signal and the one or more features may be determined. Then, in step 1025, a data structure, such as database 415 and / or 430, may be created and / or updated using the received acoustic signal, the auxiliary information, and the correlations therebetween. In some embodiments, the data structure of step 1025 may be formed via a process similar to that used to develop model 440.

[0130] As should be apparent from the foregoing discussion, aspects of the present invention relate to the use of various computer systems and computer-readable storage media having computer-readable instructions stored thereon. Figure 11An example of system 1100 is provided, which can represent any computing system that can be used to instantiate a respiratory disease model and / or perform a process or portion of a process described herein. Examples of system 1100 can include smartphones, desktop computers, laptop computers, mainframe computers, embedded systems, and the like. It should be noted that not all various computer systems have all the functionality of system 1100. For example, some of the computer systems discussed above may not include a display because the display functionality can be provided by a client computer communicatively coupled to the computer system, or the display functionality may not be necessary. These details are not critical to the present invention. System 1100 or portions thereof can, for example, be an active auscultation system such as active auscultation system 110, 200, and / or 201, a communication device such as communication device 311, a server such as server 420, and / or a computer terminal such as private access terminal 455 and public access terminal 445, and / or components thereof.

[0131] System 1100 includes a bus 1102 or other communication mechanism for communicating information, and a processor 1104 coupled to bus 1102 for processing information. Computer system 1100 also includes a main memory 1106, such as a random access memory (RAM) or other dynamic storage device, coupled to bus 1102 for storing information and instructions to be executed by processor 1104. Main memory 1106 may also be used to store temporary variables or other intermediate information during execution of instructions by processor 1104. Computer system 1100 also includes a read-only memory (ROM) 1108 or other static storage device coupled to bus 1102 for storing static information and instructions for processor 1104. A storage device 1111, such as a hard disk, a flash-based storage medium, or other storage medium readable by processor 1104, is provided and coupled to bus 1102 for storing information and instructions (e.g., an operating system, application programs, etc.).

[0132] Computer system 1100 may be coupled via bus 1102 to a display 1112, such as a flat-panel display, for displaying information to a computer user. An input device 1111, such as a keyboard including alphanumeric and other keys, may be coupled to bus 1102 to communicate information and command selections to processor 1104. Another type of user input device is a cursor control device 1116, such as a mouse, trackpad, or similar input device, for communicating directional information and command selections to processor 1104 and controlling cursor movement on display 1112. Other user interface devices, such as microphones, speakers, etc., are not shown in detail but may be involved in receiving user input and / or presenting output.

[0133] The processes referred to herein may be implemented by processor 1104 executing an appropriate sequence of computer-readable instructions contained in main memory 1106. Such instructions may be read into main memory 1106 from another computer-readable medium, such as storage device 1111, and execution of the sequence of instructions contained in main memory 1106 causes processor 1104 to perform the associated actions. In alternative embodiments, a hard-wired circuit or firmware-controlled processing unit may be used in place of or in combination with processor 1104 and its associated computer software instructions to implement the present invention. Computer-readable instructions may be presented in any computer language.

[0134] In general, all of the above process descriptions are intended to encompass any series of logical steps performed in sequence to achieve a given purpose, which is the hallmark of any computer-executable application. Unless otherwise specifically stated, it should be understood that throughout the description of the present invention, the use of terms such as "processing," "computing," "calculating," "determining," "displaying," "receiving," and "sending" refer to the actions and processes of a suitably programmed computer system, such as computer system 1100 or a similar electronic computing device, that can transform data represented as physical (electronic) quantities in registers and memories into other data similarly represented as physical quantities in memories or registers or other such information storage, transmission, or display devices.

[0135] The computer system 1100 also includes a communication interface 1118 coupled to the bus 1102. The communication interface 1118 can provide a two-way data communication channel with a computer network that provides connectivity with the various computer systems described above. For example, the communication interface 1118 can be a local area network (LAN) card that provides a data communication connection to a compatible LAN that is itself communicatively coupled to the Internet via one or more Internet service provider networks. The precise details of such a communication path are not critical to the present invention. What is important is that the computer system 1100 can send and receive messages and data via the communication interface 1118 and, in this manner, communicate with a host computer accessible via the Internet. It should be noted that the components of the system 1100 can be located in a single device or in multiple physically and / or geographically distributed devices.

Claims

1. A method of performing active auscultation, comprising: providing, via a processor in communication with the transmitter, a set of signal excitations to the transmitter to cause the transmitter to generate a set of acoustic energies directed into the user's body toward the user's lungs; receiving, by the processor from a receiver communicatively coupled to the processor, an acoustic energy response responsive to the set of acoustic energies directed into the body of the user; determining, by a processor, characteristics of an acoustic signal corresponding to the acoustic energy response, the characteristics of the acoustic signal comprising a lung resonance characteristic of the user that varies over time, wherein the lung resonance characteristic is determined by a resonant frequency and an intensity of the resonant frequency; determining, by a processor, a user's respiratory cycle based on instantaneous or rapid changes in the lung resonance characteristics; and The characteristics of the acoustic signal and the respiratory cycle are stored in a database by a processor.

2. The method according to claim 1, further comprising: The user's breathing cycle is provided to an operator via a processor.

3. The method of claim 1 or 2, wherein the set of signal excitations is a first set of signal excitations, the set of acoustic energies directed to the user's lungs is a first set of acoustic energies, the acoustic energy response is a first acoustic energy response, the resonant frequency is a first resonant frequency, and the characteristic of the acoustic signal is a characteristic of the first acoustic signal, the method further comprising: providing, by the processor, a second set of signal excitations to the transmitter to cause the transmitter to generate a second set of acoustic energy directed into the user's body toward the user's lungs; receiving, by a processor, from the receiver a second acoustic energy response responsive to a second set of acoustic energy directed into a body of a user; determining, by a processor, a characteristic of a second acoustic signal corresponding to the second acoustic energy response, the characteristic of the second acoustic signal including a second resonant frequency within the second acoustic energy response; comparing, by a processor, a characteristic of the first acoustic signal and a characteristic of the second acoustic signal; and An indication of a comparison of the characteristic of the first acoustic signal and the characteristic of the second acoustic signal is provided to an operator by a processor.

4. The method according to claim 1 or 2, further comprising: The characteristic of the acoustic signal is compared with a predetermined value by a processor.

5. The method according to claim 1 or 2, further comprising: An adjusted set of signal excitations is generated by the processor in response to a resonant frequency included in the acoustic energy response by adjusting at least one of a duration of a set of signal excitations, an intensity of a set of signal excitations, and a frequency included in the set of signal excitations.

6. The method according to claim 1 or 2, further comprising: determining, by a processor, harmonic frequencies included in the acoustic energy response; determining, by a processor, a spectral signature of a user using the harmonic frequencies; and The frequency spectrum characteristics are stored in a database through a processor.

7. A system for performing active auscultation, comprising: A processor in communication with a memory, the memory storing thereon a set of instructions that, when executed by the processor, cause the processor to: providing a set of signal excitations to the transmitter to cause the transmitter to generate a set of acoustic energy directed into the user's body toward the user's lungs; receiving an acoustic energy response from a receiver communicatively coupled to the processor, the acoustic energy response being responsive to the set of acoustic energies directed into the user's body; determining a characteristic of an acoustic signal corresponding to the acoustic energy response, the characteristic of the acoustic signal comprising a lung resonance characteristic that varies over time, wherein the lung resonance characteristic is determined by a resonant frequency and a magnitude of the resonant frequency; determining, by a processor, a user's respiratory cycle based on instantaneous or rapid changes in the lung resonance characteristics; and The characteristics of the acoustic signal and the breathing cycle are stored in a database.

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