Twelve-lead electrocardiogram using three-electrode device

Abstract

To provide a twelve-lead electrocardiogram using a three-electrode device.SOLUTION: There is provided an apparatus includes an electrocardiograph device comprising a first electrode, a second electrode, and a third electrode which are adapted to measure first, second, and third electrical signals, respectively. The apparatus further includes a processing device configured to: determine a lead I from the first and second electric signals (S3103); determine a lead II from the second and third electric signals (S3105); generate a lead III using (lead III=lead II-lead I) (S3107); determine leads aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6, using a machine learning model trained using measured twelve-lead ECG data, on the basis of the lead I, lead II and lead III, (S3109); and provide these leads, for displaying the same on a client device (S3111).SELECTED DRAWING: Figure 31

Description

Technical Field

[0001] Cross - Reference to Related Applications This application claims the benefit of U.S. Provisional Application No. 62 / 946,331, filed Dec. 10, 2019, and U.S. Non - Provisional Application No. 17 / 116,905, filed Dec. 9, 2020, the entire contents of which are incorporated herein by reference.

[0002] This disclosure relates to consumer and medical devices, systems, and methods. Specifically, this disclosure relates to devices and related systems and methods for observing a person's physiological state, and more specifically, to such devices, systems, and methods for using computing devices such as personal computers, laptop computers, tablet computers, smartphones, wearable computing devices, etc. to observe electrocardiograms (ECGs), heart rates, and arrhythmias.

Background Art

[0003] Cardiovascular diseases are a major cause of death worldwide. It can be said that 30% of the world's deaths in 2008 were due to cardiovascular diseases. It is also estimated that by 2030, more than 23 million people will die annually from cardiovascular diseases. Cardiovascular diseases are equally observed in people in high - income countries and people in low - income countries.

[0004] An arrhythmia is a condition of the heart where the electrical activity of the heart is irregular, or faster (tachycardia) or slower (bradycardia) than normal. Many arrhythmias are not life - threatening, but some can cause cardiac arrest and even sudden cardiac death. In fact, arrhythmia is one of the most common causes of death during transportation to the hospital.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

[0006] The novel features of the present disclosure are particularly set forth in the appended claims. A further understanding of the features and advantages of the present disclosure can be obtained by reference to the following detailed description that describes embodiments for explaining the principles of the present invention and the accompanying drawings of the embodiments. [Brief Description of the Drawings]

[0007]

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[0008] Devices, systems, and methods are disclosed for measuring and observing biometric or physiological parameters in a user-friendly and convenient manner.

[0009] It should be understood that the applications of the present disclosure are not limited to the configurations, experiments, exemplary data, and / or details of component arrangements described in the following description. The inventions of the present disclosure can have other embodiments or can be practiced or carried out in various ways. Also, it should be understood that the terms employed herein are for the purpose of description and should not be regarded as limiting.

[0010] In the following detailed description of embodiments of the present disclosure, numerous specific details are set forth in order to provide a more thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the concepts within the present disclosure can be practiced without these specific details. In other instances, well-known features are not described in detail to avoid unnecessarily complicating the description.

[0011] Atrial fibrillation (A-fib) is the most common arrhythmia. In A-fib, the electrical conduction through the ventricles is irregular and disrupted. A-fib may not cause symptoms, but it is often associated with palpitations, shortness of breath, fainting, chest pain, or congestive heart failure, and also increases the risk of stroke. Usually, A-fib is diagnosed by taking an electrocardiogram (ECG) of the subject. To treat A-fib, patients may take medications to slow the heart rate or regulate the rhythm of the heart. Patients may also take anticoagulants to prevent strokes or undergo surgical procedures, including heart ablation, to treat A-fib.

[0012] Often, patients suffering from arrhythmias or A-fib are observed for long periods to manage the disease. For example, a patient may be provided with a Holter monitor or other wearable electrocardiogram recording device to continuously observe the electrical activity of the cardiovascular system for at least 24 hours.

[0013] Electrocardiogram recording methods are used to examine the electrical activity of the heart and can be used for both diagnosis and treatment. Electrocardiograms (ECGs) can be recorded or taken using electrodes placed at multiple positions on a patient's skin. The electrical signals recorded between electrode pairs are called leads. A variable number of leads can be used to take an ECG, and different combinations of electrodes can be used to form various leads. Examples of the number of leads used to take an ECG are one, three, five, and twelve leads. In a 12-lead ECG, ten electrodes may be used, six on the patient's chest and one each on the arms and legs.

[0014] There are various "standard" configurations of electrode placement that can be used to attach electrodes to a patient. For example, the arm and leg electrodes can be placed closer to the chest or closer to the ends of the arms / legs. The various placements of electrodes on the arms and legs can affect the ECG and make it more difficult to compare to a standard ECG.

[0015] Standard or conventional 12-lead ECG configurations use ten electrodes. FIG. 1 shows a pictorial representation of ten electrodes, with six electrodes on the patient's chest and one electrode each on the patient's arms and legs. The electrode placed on the right arm may be called RA. The electrode placed on the left arm may be called LA. The RA electrode and the LA electrode are preferably placed near the wrist at the same position for the left and right arms. The leg electrodes may be called RL for the right leg and LL for the left leg. The RL electrode and the LL electrode are preferably placed near the ankle at the same position for the left and right legs.

[0016] In another embodiment, a 12-lead ECG can be generated using three electrodes (e.g., by a device including three electrodes). For example, in one embodiment, a device having three electrodes as described herein can be used to simultaneously determine Lead I (e.g., the voltage between the left and right arms) and Lead II (e.g., the voltage between the left leg and the right arm), and to simultaneously determine Lead I and another one of the chest leads such as Lead V2 or V5. In other embodiments, any other combination of leads is possible. The processing logic can then align two sets of recordings using Lead I or another lead that is common in the measurement in time, so that the two sets of measurement results can be compared over the same simulated period.

[0017] The processing logic can further transform the two sets of leads to generate a complete 12-lead ECG. In one embodiment, the processing logic can perform such a transformation using a machine learning model (e.g., a neural network, deep learning techniques, etc.). The machine learning model can be trained using 12-lead ECG data corresponding to a population of individuals. The data can be preprocessed to filter the data in a manner suitable for the application before being input into the machine learning model. For example, the data may be classified according to height, gender, weight, nationality, etc. before being used to train one or more machine learning models, whereby the resulting one or more models are fine-tuned according to a particular type of individual. In a further embodiment, the machine learning model can be further trained based on the user's unique ECG data to fine-tune and personalize the model and further reduce any remaining synthetic error.

[0018] In one embodiment, using the machine learning techniques described herein, a complete 12-lead ECG can be generated using only three electrodes of a single form factor. As described herein, the three electrodes may be arranged on the device in any suitable manner, which includes an arrangement of two electrodes on the front of the device and one electrode on the back.

[0019] Figures 7 and 8 show the placement of six electrodes labeled V1, V2, V3, V4, V5, and V6 on the chest. V1 is placed, for example, in the fourth intercostal space between ribs 4 and 5, just to the right of the sternum. V2 is placed, for example, in the fourth intercostal space between ribs 4 and 5, just to the left of the sternum. V3 is placed between electrodes V2 and V4. V4 is placed in the fifth intercostal space between ribs 5 and 6 on the midclavicular line. V5 is placed at the same height as V4 on the left axillary line. V6 is placed at the same height as V4 and V5 on the midclavicular line.

[0020] Lead I is typically the voltage between the left arm (LA) and the right arm (RA), for example, I = LA - RA. Lead II is typically the voltage between the left leg (LL) and the right arm (RA), for example, II = LL - RA. Lead III is typically the voltage between the left leg (LL) and the left arm (LA), for example, III = LL - LA. Wilson's central terminal (WCT or VW) can be calculated by (RA + LA + LL) / 3. Assuming that both Lead I and II are recorded with RA as the reference so that the voltage of RA can be regarded as 0, WCT (VW) can be calculated as Lead I + Lead II / 3.

[0021] Augmented limb leads can also be determined from RA, RL, LL, and LA. Augmented vector right (aVR) is equal to RA - (LA + LL) / 2 or -(I + II) / 2. Augmented vector left (aVL) is equal to LA - (RA + LL) / 2 or I - II / 2. Augmented vector foot (aVF) is equal to LL - (RA + LA) / 2 or II - I / 2.

[0022] I, II, III, aVR, aVL, and aVF can all be represented in the hexaxial system. Errors or displacements in the electrode placement may change the results of the ECG in the hexaxial system.

[0023] However, current ambulatory electrocardiogram recording devices such as Holter monitors are usually bulky and difficult for a subject to attach without the assistance of a medical professional. For example, use of a Holter monitor requires the patient to wear a large device on the chest and accurately place multiple electrodes in precise locations on the chest. These requirements can interfere with the subject's activities, including natural movement, bathing, and showering. When a full-disclosure ECG is generated, the ECG is transmitted to the patient's physician, who then analyzes the ECG and makes a diagnosis and other recommendations. Currently, this process often must be carried out through hospital administrators and health management organizations, and many patients do not receive feedback in a convenient manner.

[0024] There are several handheld ECG measurement devices known that include a device that can adapt an existing mobile remote communication device (e.g., a smartphone) to be used for recording an ECG. However, such devices either require the use of external (e.g., plug-in) electrodes or include electrodes within the housing that are difficult to properly hold and attach to the body.

[0025] Wearable monitors for detecting one or more biometric parameters (including the subject's movement, heart rate, body temperature, ECG, etc.) typically must communicate wirelessly to an observation, analysis, or recording station (an "observation station"). Usually, the transmission of information is carried out by short-wavelength wireless transmission (e.g., "Bluetooth"). In particular, although some embodiments are described with respect to ultrasonic communication, Bluetooth communication is considered at least equally applicable to the technology described, and ultrasonic is proposed only as a non-limiting example of any number of other suitable communication technologies. Those skilled in the art will be so recognized.

[0026] In some situations where it is desirable for the device to be lightweight so that it can be comfortably worn during normal daily activities or exercise, many manufacturers have chosen to record data rather than transmit it and to periodically download the data via a direct connection to an observation station. It would be advantageous to provide an observation device (e.g., a wristlet) that can be worn on the wrist by a subject, or an observation device that can be worn on other body areas where reliable low-energy wireless transmission of data is possible.

[0027] For example, heart observation devices such as those described in U.S. Patent Nos. 4,221,223, 4,295,472, and 4,230,127 describe a wristwatch-sized wearable monitor that can detect ECG signals from a patient wearing the device. These signals can be displayed on the device. These signals are not transmitted. Other similar devices are described in U.S. Patent No. 4,938,228. U.S. Patent Nos. 5,351,695 (all in Mils), 5,333,616, 5,317,269, and 5,289,824 describe improvements to this device, which includes an integrated hearing-aid type speaker that uses audible sound (e.g., between 1 kHz and 3 kHz), uses sound on the voice channel of a telephone, and transmits the ECG signal via a telephone line. The ECG signal is typically digitized and frequency modulated (e.g., as a frequency shift keyed signal). Unfortunately, such devices are literally noisy, generate audible signals, require a large amount of power to generate and transmit, and are not capable of two-way communication, particularly with mobile remote communication devices.

[0028] The following patent documents, namely U.S. Patent Nos. 5,735,285, 6,264,614, 6,685,633, 6,790,178, 8,301,232, 8,509,882, and 8,615,290, as well as U.S. Patent Application Publication No. 2011 / 0015496, may also be relevant.

[0029] Ultrasonic transmission shares many similarities with electrical transmission, but there are also significant differences, including differences that were previously considered drawbacks. Furthermore, techniques such as frequency shift keying for digitizing information are known, but implementing such techniques on a timescale that makes them practical for use in medical (e.g., ECG) monitoring has been difficult and unrealistic. In particular, the transmission of ultrasonic data has, until now, had somewhat limited information content. For example, the digital encoding of information by ultrasound has had limited amounts and content of information being transmitted. There are also no standards for the transmission or encoding of ultrasonic transmission. Furthermore, such ultrasonic signals are not typically encrypted.

[0030] Accordingly, it would be advantageous to provide systems, devices, and methods for encoding or organizing the information transmitted by ultrasonic transmission. In particular, it would be advantageous to encode information in a way that circumvents the limitations of ultrasonic transmission (as opposed to electromagnetic or audible). Additionally, it would be useful to provide methods, devices, and systems for securely transmitting (e.g., encrypting and / or decrypting) ultrasonic transmission. For example, it would be useful to dynamically pair one or more receiving devices with a device (e.g., a wristlet) that transmits ECG information via ultrasound.

[0031] Methods, devices, and systems are described herein for receiving and transmitting information (including but not limited to digital health information) that is encoded by an application device into an ultrasonic signal that can be listened to by a remote communication device and then stored, transmitted, and / or analyzed by the remote communication device, using one or more widely available remote communication devices (including mobile remote communication devices) such as smartphones, tablet computers, portable computers, or desktop computers (or adapted for use therewith). In particular, methods, devices, and systems are described herein for encoding information such that only an authorized remote communication device can interpret the information. The systems, devices, and methods (including executable logic) can include techniques for facilitating the provision of an authorization in a manner different from ultrasonic transmission (e.g., optically).

[0032] U.S. Patent Application No. 12 / 796,188, filed Jun. 8, 2010, now U.S. Patent No. 8,509,882, entitled "HEART MONITORING SYSTEM USABLE WITH A SMART PHONE OR COMPUTER"; and U.S. Patent Application No. 13 / 108,738, filed May 16, 2011, now U.S. Patent Application Publication No. US / 2011 / 0301439-A1, entitled "WIRELESS, ULTRASONIC PERSONAL HEALTH MONITORING SYSTEM", describe an ECG monitor that converts ECG data into an ultrasonic signal that can be received by a remote communication device such as a smartphone and then stored, analyzed, and / or displayed. This application extends and adapts this teaching and can be used with any of the systems, methods, and devices described herein.

[0033] Accordingly, there is a need for improved heart disease and / or arrhythmia management and monitoring devices, systems, and methods for addressing one or more of the above problems.

[0034] Devices, systems, and methods are disclosed for measuring and observing biometric or physiological parameters in a user-friendly and convenient manner. In particular, while a user is operating a computing device, or other manual or handheld device in a normal manner, relevant physiological parameters of the user can be measured. For example, the system of the present disclosure can enable one or more physiological parameters of a user to be measured while the user is operating a computing device, such as a laptop, a tablet computer, or a smartphone, in a normal manner. The one or more physiological parameters can be measured using an accessory of a computing device, such as a laptop case, a tablet computer case, or a smartphone case. Normal use of the computing device can include web browsing, reading and writing emails or text messages, playing games, or using other common applications, such as books or text readers. The physiological parameter observation and measurement application of the present disclosure can operate in the background while the computing device is in normal use.

[0035] Aspects of the present disclosure provide a system for measuring a user's cardiac parameters. The system can include a device configured to couple to a computing device and a first application loaded onto the computing device. The device can include a sensor for measuring cardiac parameters. The first application can be configured to receive the cardiac parameters measured by the sensor. The sensor may measure the cardiac parameters, and the first application may receive the measured cardiac parameters simultaneously with the second application being loaded onto the computing device and operated by the user.

[0036] The cardiac parameter(s) may include one or more of heart rate, heart rate variability, blood pressure, blood pressure variability, arrhythmia, seismocardiogram (SCG), SCG parameter, electrocardiogram (ECG), or ECG parameter. In many embodiments, the cardiac parameter(s) include electrocardiogram (ECG) or ECG parameter(s).

[0037] The computing device may include one or more of a personal computer, laptop computer, tablet computer, personal digital assistant (PDA), smartphone, or wearable computing device. In many embodiments, the computing device includes a tablet computer or smartphone. The device may be configured to removably couple to the computing device and may include a cover for covering the computing device, such as a tablet computer case or smartphone case or cover.

[0038] A sensor for measuring cardiac parameters may comprise first and second electrodes configured to generate a signal comprising cardiac parameters when in contact with a user. For example, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left arm to generate a Lead I ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left leg to generate a Lead II ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's left arm, and the second electrode may be configured to contact the user's left leg to generate a Lead III ECG. The sensor may further comprise a third electrode for contact configured to generate a signal comprising cardiac parameters when in contact with the user. The first, second, and third electrodes may be used simultaneously, for example, to generate one or more of Lead I, Lead II, or Lead III ECG. The first electrode may be configured to contact the user's right arm, the second electrode may be configured to contact the user's left arm, and the third electrode may be configured to contact the user's left leg.

[0039] The first application may further be configured to display the measured heart parameters, for example, on a display of a computing device. The heart parameters may be displayed in real time. The first application may further be configured to store the measured heart parameters in a memory of the computing device. The first application may further be configured to transmit the measured heart parameters to a remote computing device, such as a remote server. The remote computing device may store heart or other physiological parameter data and may enable access to such data by medical professionals and other experts for analysis, interpretation, and / or diagnosis of the data. The analysis and diagnosis may be returned to the user through the remote computing device and the user's computing device or through other channels such as email, text messaging, or other electronic alerts. Alternatively, or in combination, one or more of the first application loaded on the computing device, another application loaded on the remote server, or another application used by a medical professional or expert may automatically generate such analysis, interpretation, and / or diagnosis of the data.

[0040] The operations of the second application can include one or more of typing on the keyboard of the second application, scrolling on the second application, zooming in or out in the second application, entering data into the second application in other ways, etc. By enabling the user to operate a second application loaded on the computing device while the first application measures and observes the user's heart parameters and other health parameters, embodiments of the present disclosure enable user-friendly, convenient, less invasive and less bothersome measurements and observations of heart parameters and other health parameters. For example, while the first application and the cover of the computing device measure and / or observe the user's ECG or other heart parameters and physiological parameters in the background, the user can hold the computing device and operate it normally to check emails, browse the web, or operate a mobile application.

[0041] Aspects of the present disclosure also provide a method for measuring a user's heart parameters. An apparatus comprising a sensor for heart parameters can be coupled to a computing device. The user's heart parameters can be measured using the sensor. The measured heart parameters can be transmitted to a first application loaded on the computing device using the apparatus. The heart parameters may be measured while the user operates a second application loaded on the computing device, and the first application may receive the transmitted measured heart parameters.

[0042] The heart parameters can include one or more of heart rate, heart rate variability, blood pressure, blood pressure variability, arrhythmia, seismocardiogram (SCG), SCG parameters, electrocardiogram (ECG), or ECG parameters. In many embodiments, the heart parameters include an electrocardiogram (ECG) or ECG parameters.

[0043] The computing device may comprise one or more of a personal computer, a laptop computer, a tablet computer, a personal digital assistant (PDA), a smartphone, or a wearable computing device. In many embodiments, the computing device comprises a tablet computer or a smartphone. The device may be coupled to the computing device by removably attaching the device to the computing device. For example, the device may comprise a cover for covering the computing device, such as a tablet computer case or a smartphone cover. Also, the method may comprise at least partially surrounding a computing device, such as a tablet computer or a smartphone, with a case or a cover.

[0044] The cardiac parameter can be measured using a sensor by measuring the cardiac parameter at the first and second electrodes of the sensor. The first and second electrodes can be configured to generate a signal comprising the cardiac parameter when contacting the user. For example, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left arm to generate a Lead I ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left leg to generate a Lead II ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's left arm, and the second electrode may be configured to contact the user's left leg to generate a Lead III ECG. The cardiac parameter may also be measured using a third electrode of the sensor, and the third electrode is configured to generate a signal comprising the cardiac parameter when contacting the user. The first, second, and third electrodes can be used simultaneously, for example, to generate one or more of Lead I, Lead II, or Lead III ECG. The first electrode may be configured to contact the user's right arm, the second electrode may be configured to contact the user's left arm, and the third electrode may be configured to contact the user's left leg.

[0045] Furthermore, the received and measured heart parameters can be displayed on the display of the computing device. The heart parameters can be displayed in real time. Also, the measured heart parameters can be stored in the memory of the computing device. The measured heart parameters can also be transmitted to a remote computing device such as a remote server. The remote computing device can store the heart parameter data or other physiological parameter data and enable access to such data by medical experts and other professionals for analysis, interpretation, and / or diagnosis of the data. The analysis and diagnosis can be returned to the user through the remote computing device and the user's computing device, or through other channels such as email, text messaging, or other electronic alerts. Alternatively, or in combination, one or more of a first application loaded on the computing device, another application loaded on the remote server, or another application used by a medical expert or professional can automatically generate such analysis, interpretation, and / or diagnosis of the data.

[0046] The operations of the second application may include one or more of typing on the keyboard of the second application, scrolling on the second application, zooming in or out in the second application, entering data into the second application in other ways, etc. By enabling the user to operate the second application loaded on the computing device while the first application measures and observes the user's heart parameters and other health parameters, embodiments of the present disclosure enable user-friendly, convenient, less invasive and less annoying measurements and observations of heart parameters and other health parameters. For example, while the first application and the cover of the computing device measure and / or observe the user's ECG or other heart parameters and physiological parameters in the background, the user can hold the computing device and operate it normally to check emails, browse the web, or operate a mobile application. In some embodiments, the first application may cause the computing device to warn the user if the health parameter sensor is mispositioned and thus unable to make or should not be able to make appropriate measurements (i.e., a pop-up may appear in the second application).

[0047] Aspects of the present disclosure also provide a system for measuring a user's cardiac parameters. The system may include a cover configured to be removably attached to a portable computing device. The portable computing device may include a front face, a back face, and an edge between the front and back faces. The cover may include a plurality of sensor electrodes configured to measure cardiac parameters and disposed on the edge of the portable computing device when the cover is attached to the portable computing device. In many embodiments, the plurality of sensor electrodes are disposed only on the edge of the portable computing device. The portable computing device may include a laptop computer, a tablet computer, a personal digital assistant (PDA), or a smartphone.

[0048] The cardiac parameters may include one or more of heart rate, heart rate variability, blood pressure, blood pressure variability, arrhythmia, systolic cardiac graph (SCG), SCG parameters, electrocardiogram (ECG), or ECG parameters. In many embodiments, the cardiac parameters include an electrocardiogram (ECG) or ECG parameters.

[0049] The plurality of sensor electrodes may include a first sensor electrode and a second sensor electrode. The first sensor electrode and the second sensor electrode may be configured to generate a signal with cardiac parameters when they contact the user's first limb and second limb, respectively. For example, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left arm to generate Lead I ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's right arm, and the second electrode may be configured to contact the user's left leg to generate Lead II ECG. Alternatively, or in combination, the first electrode may be configured to contact the user's left arm, and the second electrode may be configured to contact the user's left leg to generate Lead III ECG. The plurality of sensor electrodes may further include a third sensor electrode configured to generate a signal with cardiac parameters when it contacts the user's third limb. The cardiac parameters may also be measured using the third electrode of the sensor, and the third electrode is configured to generate a signal with cardiac parameters when it contacts the user. The first, second, and third electrodes may be used simultaneously, for example, to generate one or more of Lead I, Lead II, or Lead III ECG.

[0050] The system may further comprise a first application loaded onto the portable computing device. The first application may be configured to receive cardiac parameters measured from a plurality of sensor electrodes. The first application may receive the measured cardiac parameters at the same time that a second application is loaded onto the portable computing device and operated by the user. The operation of the second application may include one or more of typing on the keyboard of the second application, scrolling on the second application, zooming in or out in the second application, and entering data into the second application in other ways. By enabling the user to operate a second application loaded onto the computing device while the first application measures and observes the user's cardiac parameters and other health parameters, embodiments of the present disclosure enable user-friendly, convenient, less invasive and less bothersome measurement and observation of cardiac parameters and other health parameters. For example, while the first application and the cover of the computing device measure and / or observe the user's ECG or other cardiac parameters and physiological parameters in the background, the user can hold and normally operate the computing device to check emails, browse the web, or operate a mobile application.

[0051] The first application may be configured to display on a display of a portable computing device the received heart parameters. The received heart parameters may be displayed in real time. The first application may further be configured to store in a memory of the portable computing device the measured heart parameters. The first application may further be configured to transmit to a remote computing device, such as a remote server, the measured heart parameters. The remote computing device may store the heart parameter data or other physiological parameter data and may enable access to such data by medical professionals and other experts for analysis, interpretation, and / or diagnosis of the data. The analysis and diagnosis may be returned to the user through the remote computing device and the user's computing device or through other channels such as email, text messaging, or other electronic alerts. Alternatively, or in combination, one or more of the first application loaded on the computing device, another application loaded on the remote server, or another application used by a medical professional or expert may automatically generate such analysis, interpretation, and / or diagnosis of such data.

[0052] Aspects of the present disclosure also provide a method for measuring a user's heart parameters. A cover may be removably attached to a portable computing device. The portable computing device may comprise a front face, a back face, and an edge between the front and back faces. The first and second electrodes of the cover may each contact the user's first and second extremities to generate a signal comprising the heart parameters. The first and second electrodes of the cover may be disposed on the edge of the portable computing device. In many embodiments, the plurality of sensor electrodes may be disposed only on the edge of the portable computing device. The portable computing device may comprise a laptop computer, a tablet computer, a personal digital assistant (PDA), or a smartphone.

[0053] The cardiac parameter(s) may comprise one or more of heart rate, heart rate variability, blood pressure, blood pressure variability, arrhythmia, vibration cardiogram (SCG), SCG parameter, electrocardiogram (ECG), or ECG parameter. In many embodiments, the cardiac parameter comprises an electrocardiogram (ECG) or an ECG parameter.

[0054] To generate a signal comprising a cardiac parameter, a third electrode may contact a third limb of the user. The first limb may comprise the right arm, the second limb may comprise the left arm, and the third limb may comprise the left foot. These three limbs may contact the first, second, and third electrodes, respectively, simultaneously to generate lead I ECG, lead II ECG, and lead III ECG simultaneously. Alternatively, the first and second electrodes may be used to generate lead I ECG, lead II ECG, and lead III ECG. For example, the first electrode may be configured to contact the right arm of the user, and the second electrode may be configured to contact the left arm of the user to generate lead I ECG. Alternatively, or in combination, the first electrode may be configured to contact the right arm of the user, and the second electrode may be configured to contact the left foot of the user to generate lead II ECG. Alternatively, or in combination, the first electrode may be configured to contact the left arm of the user, and the second electrode may be configured to contact the left foot of the user to generate lead III ECG. Alternatively, or in combination,

[0055] The first application can be loaded onto a tablet computer or a smartphone. The first application can be configured to receive heart parameters measured from a plurality of sensor electrodes. The first application can receive the measured heart parameters at the same time as the second application is loaded onto the computing device and operated by the user. The operation of the second application can include one or more of typing on the keyboard of the second application, scrolling on the second application, zooming in or out in the second application, entering data into the second application in another manner, etc. By enabling the user to operate the second application loaded onto the computing device while the first application measures and observes the user's heart parameters and other health parameters, embodiments of the present disclosure enable user-friendly, convenient, less invasive and less annoying measurements and observations of heart parameters and other health parameters. For example, while the cover of the first application and the computing device measures and / or observes the user's ECG or other heart parameters and physiological parameters in the background, the user can hold the computing device and operate it normally to check emails, browse the web, or operate a mobile application.

[0056] The received heart parameters can be displayed on the display of a tablet computer or a smartphone using a first application. The received heart parameters can be displayed in real time. The measured heart parameters can be stored in the memory of a computing device. The measured heart parameters can be transmitted to a remote computing device such as a remote server. The remote computing device can store heart or other physiological parameter data and enable access to such data by medical experts and other professionals for analysis, interpretation, and / or diagnosis of the data. The analysis and diagnosis can be returned to the user through the remote computing device and the user's computing device, or through other channels such as email, text messaging, or other electronic alerts. Alternatively, or in combination, one or more of a first application loaded on a computing device, another application loaded on a remote server, or another application used by a medical expert or professional can automatically generate such analysis, interpretation, and / or diagnosis of such data.

[0057] Aspects of the present disclosure also provide a system for measuring a user's cardiac parameters. The system may include a sensor device and an application. The device may be configured to couple to a keyboard of a computing device, a steering wheel of a motor-driven vehicle, or a handlebar, seat, chair, glasses, clothing, etc. of an exercise machine such as a bicycle, bike, treadmill, elliptical machine, or weightlifting machine. The device may include a sensor for measuring cardiac parameters. The device may be configured to receive cardiac parameters measured from the sensor when a keyboard of a computing device, a steering wheel of a motor-driven vehicle, or a handlebar of a bicycle, bike, or exercise machine is touched, held, or manipulated. Further methods and systems are contemplated for conveniently, non-invasively, and unobtrusively measuring and observing cardiac parameters and other physiological parameters while a user ordinarily operates a computing device or other device in contact with the user's body.

[0058] The present disclosure also describes a system, software, and apparatus including a device for taking electrocardiogram (ECG) information from a subject using an interface compatible with a mobile remote communication device having three electrodes, as well as methods (including methods for using these devices). Devices for detecting an ECG that can address problems including, but not limited to, those identified above using currently available ECG detection systems are described herein.

[0059] Generally, the devices (including devices and systems) and methods described herein are for use in detecting biological signals such as electrocardiograms (ECGs). In particular, devices for use with mobile remote communication devices are described herein so that the mobile remote communication devices can receive biological signals measured directly from a patient. The device typically includes three or more electrodes (or just three electrodes) for receiving signals such as voltage or current from the patient's body. The device may also include a housing. A housing such as a "case" may be configured to hold the mobile remote communication device or connect directly to the mobile remote communication device. One or more electrodes may be disposed directly on the outer surface of the housing. The device may also include one or more transmitters for the detected communication signal including a modified / processed version of the detected signal from the electrodes to the mobile remote communication device. The mobile remote communication device may be connected to the housing and may be within or near, for example, a case formed by the housing. In some variations, the device may include one or more processing devices for processing the signal detected by the electrodes.

[0060] Any suitable transmitter including a wireless transmitter may be used. In some variations, the wireless transmitter may be an ultrasonic transmitter that uses non-audible ultrasonic waves (e.g., >10 kHz, >12 kHz, 15 >kHz, >18 kHz, >19 kHz) that can be received, transmitted, and / or further processed by a microphone of the mobile remote communication device. Examples of such systems are described in U.S. Patent No. 8,301,232, U.S. Patent Application Publication Nos. 2011 / 0301435 and 2011 / 0301439, and International Publication No. 2013 / 023370, each of which is incorporated herein by reference in its entirety.

[0061] The devices described herein can be configured to be held by a patient against a patient's leg (e.g., left or right leg) using both hands to measure six of the "leads" from the patient (Leads I - III, and augmented leads aVR, aVL, aVF). In some variations, the device can be configured such that the patient holds the device (surrounding a mobile remote communication device) against a leg (right or left) with both hands and can easily view the screen of the mobile remote communication device while recording signals independently from each of the right arm, left arm, and right or left leg. Thereby, the patient can receive immediate visual feedback from the device, including providing guidance (using the screen or audio output of the mobile remote communication device) to adjust or correct electrode contact or placement and / or to display one or more ECG signals as the measurements are taken. Thus, the device can be easily held to enable electrically separate measurements from each arm (right, left) and leg (left or right), yet be configured as described herein such that a subject holding the device can observe the screen of the mobile remote communication device coupled to the device.

[0062] Generally, the patient (as used herein) can be a human patient or, without limitation, a non - human patient including an animal (such as a dog, cat, horse, etc.). Thus, any of the devices or methods described herein may be used for veterinary applications or configured as veterinary products.

[0063] Generally, a mobile remote communication device can include any mobile remote communication device such as, but not limited to, a mobile (e.g., cellular) phone or the like, including an iPhone (registered trademark), Droid (trademark), etc. The mobile remote communication device can include a processing device or other computing module / device that can surround software, hardware, etc., and that is typically configured to operate the device to receive and / or transmit information from the devices described herein. Such code can be provided with, or separately from, the devices described. The mobile remote communication device can be referred to as (and include) a cell phone or cellular phone or cell telephone or cellular telephone, mobile phone or mobile telephone, smartphone, handheld computer, tablet, wearable computer, etc. The code can be referred to as software, or application software (“app” or “application”), and can be downloaded to the mobile remote communication device from a remote location.

[0064] For example, an electrocardiogram (ECG) detection device for use with a wireless remote communication device is described herein. In some variations, the device includes a case configured to fit over the remote communication device, the case having an outer back, at least two outer sides perpendicular to the back, and a front region through which a screen of the remote communication device held within the case can be viewed; a first electrode on or adjacent to one of the at least two outer sides; a second electrode on the outer back, the second electrode having an outer contact surface; and a third electrode on the outer back, the third electrode having an outer contact surface, wherein the outer contact surfaces of the second and third electrodes are recessed relative to at least a portion of the outer back such that when the case is placed on a table surface with the outer back facing the table surface, the outer contact surfaces of the second and third electrodes do not contact the table surface, and further, the second and third electrodes are arranged such that a patient can touch the outer contact surface of the second electrode with only the left hand and the outer contact surface of the third electrode with only the right hand, and can view the screen of the remote communication device held within the case while holding the first electrode against a leg.

[0065] When the device is configured as a case, the case can be configured to hold the mobile remote communication device within a cavity or otherwise to cover and apply to the mobile remote communication device. Thus, the case may include an inner surface or a surface for holding the mobile remote communication device and may have a front region through which the screen and / or any controls of the mobile remote communication device can be viewed and / or operated. For example, the case may include a cutout region or a transparent cover through which the mobile remote communication device can be viewed. Electrodes can be mounted on the case. The case may also include one or more other openings for accessing the control, input, output, or connection regions (e.g., jacks, plug-in receptacles, etc.) of the mobile remote communication device. Generally, the electrodes are arranged on the case such that (1) the electrodes are protected from contact with surfaces, particularly metal surfaces, when the device is not in use, and (2) a patient holding the device against a leg can contact the electrodes while easily viewing the screen for simultaneous recording from both arms (through the hands) and the leg. The case may also house additional components such as a transmitter, a power source (e.g., a battery, a solar cell, etc.), and / or a processing device or other circuitry for conditioning, amplifying, filtering, or otherwise modifying the signals received by the electrodes. In some variations, the device can be configured such that one of the electrodes (e.g., a second or third electrode) can function as a reference electrode with respect to the other two (or possibly more) electrodes.

[0066] In a variation where the case may include one or more attachment areas for one or more of the electrodes. For example, it may include an opening on the back for interfacing with an electrode unit that may be used with cases having various configurations (e.g., for fitting mobile remote communication devices of various sizes). All three electrodes may be part of the same electrode unit, or multiple electrode units may be used. The electrode unit may include additional hardware such as the processing device mentioned, and may also include a power source or other electronic components.

[0067] The second and third electrodes are typically each configured to be easily contacted by the patient's hand. For example, the position and size of the second electrode can be determined such that the patient can touch the second electrode with the left hand while also touching the third electrode of appropriate shape and size with the right hand. For example, in some variations, the second and third electrodes are entirely on the outer back. The second electrode may be in the upper / left half of the back of the case (relative to the mobile remote communication device), while the third electrode is disposed in the lower / right half of the back of the case. The second and third electrodes can be separated by a gap in size and / or shape that prevents overlap of contact with the left hand and the right hand. Generally, the patient should only touch each electrode with one hand.

[0068] The second and third electrodes may be formed of any suitable conductive material (including metals, alloys, etc.) and may be sized to be easily contacted by one or more fingers (or the palm) of the patient holding the device. In some variations, the second and third electrodes are symmetrically disposed relative to each other from the center of the outer back.

[0069] The first electrode can be configured to be easily held against a patient's leg while holding the case and touching the second and third electrodes with the left and right hands respectively. Thus, in some variations, the first electrode is disposed entirely laterally to the case (e.g., on one of at least two outer sides). Alternatively, the first electrode is on the back of the case such that the first electrode can be held against the leg when the edge of the case is held against the leg, but may extend along the edge. Thus, the first electrode may be on the back, but may abut or be adjacent to a side (one of at least two outer sides). In some variations, the first electrode extends laterally from the back of the case to cover the edge of the case, for example, bent along the edge of the case. Thus, the first electrode may extend to cover the edge between the outer back and one of the outer sides. Any of these configurations can allow the case of the mobile remote communication device to be held at an angle to the patient's leg such that the patient can hold the case with both hands, touch the second and third electrodes, and make good contact with the leg while viewing the screen of the mobile remote communication device.

[0070] Thus, generally, the first electrode may extend over the entire length or a part (e.g., more than half) of one side of the case. If the first electrode is on or near the edge of the case and extends over all or a significant portion (e.g., between about 100% and about 50%, between about 90% and about 60%, about 75%) of the edge of the case, it may be easier to hold and contact the case against the leg as described and shown herein. For example, the outer side of the case may generally be rectangular. The first electrode may be centered between the two short sides of one of the outer sides and have a major axis extending in the direction of the long side of one of the outer sides. As mentioned, the first electrode may extend over more than half of the length of the outer side, over or near the outer side.

[0071] In some variations, the device has only three electrodes (e.g., the first, second, and third electrodes) on the outer surface of the case.

[0072] Generally, the device can be configured such that when the device is placed on a table with the electrodes (first and / or second and third) facing the table, the electrodes do not contact the table surface. This allows the device to be placed on a metal surface, as is common in a hospital or other medical environment, without creating a conductive path between the electrodes and thus without the possibility of discharge (and / or leakage of power from the device). In some variations, the electrodes are recessed relative to the outer back surface. For example, the electrodes may be embedded within the material forming the case. Alternatively, or in addition, the case may include one or more protrusions that can support the case when placed with the back side down, preventing one or more electrodes from contacting the surface. For example, the outer back surface of the case may include one or more spacers configured to extend a portion of the outer back surface relative to the outer contact surfaces of the first and second surfaces such that the outer contact surface is recessed relative to the outer surface of one or more "spacers". Generally, a spacer can refer to a protrusion from the back surface having a height greater than the height of the electrode relative to the back surface of the device. For example, the spacer can be a bump, island, bar, piece, tab, etc. that extends from the back surface and in some variations is around the electrode (e.g., completely or partially surrounding the electrode).

[0073] Generally, the electrodes can have a sufficient surface area for easy and reliable contact with the patient's hand and / or leg. The first (leg) electrode can be of a different shape or size than the second and third electrodes. In some variations, the surface areas of the three electrodes are approximately the same. In some variations, the surface area of the second or third (reference) electrode is wider than the other electrodes.

[0074] As noted, any of the devices described herein may include a transmitter for communicating with a wireless remote communication device. The transmitter may generally be wireless, or the transmitter may be directly connected (plugged in) to the wireless remote communication device. An electromagnetic transmitter (including near-field transmitter, radio frequency (RF) transmission, etc.), an optical transmitter, or any other type of transmitter may be used. In particular, an ultrasonic transmitter that may be integrated into the device is described herein.

[0075] For example, an electromagnetic (ECG) detection device for use with a wireless remote communication device is described herein, the device comprising a case configured to conform over the remote communication device, the case having an outer back surface, at least two outer side surfaces perpendicular to the back surface, and a front region through which the screen of the remote communication device held within the case can be viewed, a first electrode on or adjacent to one of the at least two outer side surfaces, a second electrode on the outer back surface, the second electrode having an outer contact surface, a third electrode on the outer back surface, the third electrode having an outer contact surface, and an ultrasonic transmitter configured to transmit signals detected from the first, second, and third electrodes to the wireless remote communication device by ultrasound, the outer contact surfaces of the second and third electrodes being recessed with respect to at least a portion of the outer back surface such that the outer contact surfaces of the second and third electrodes do not contact the table surface when the case is placed on the table surface with the outer back surface facing the table surface.

[0076] Methods of using any of the described devices are also described herein. For example, a method of generating an electrocardiogram (ECG) from a patient using a handheld wireless remote communication device case having three electrodes on an outer surface of the case is described herein. The method includes instructing the patient to hold the first electrode along the side of the case against the leg while simultaneously touching the second electrode behind the case with the right hand and the third electrode behind the case with the left hand such that the patient does not touch more than three electrodes on the case, detecting a first lead signal (lead I) of the ECG between the third electrode and the second electrode, detecting a second lead signal (lead II) of the ECG between the second electrode and the first electrode, and detecting a third lead signal (lead III) of the ECG between the first electrode and the third electrode.

[0077] A method of generating an electrocardiogram (ECG) from a patient using a handheld wireless remote communication device case having three electrodes on an outer surface of the case is also described herein. The method includes instructing the patient to hold the first electrode of the case against the leg while simultaneously touching the second electrode with the right hand and the third electrode with the left hand such that the patient does not touch more than three electrodes on the case, detecting a first lead signal (lead I) of the ECG between the third electrode and the second electrode, detecting a second lead signal (lead II) of the ECG between the second electrode and the first electrode, detecting a third lead signal (lead III) of the ECG between the first electrode and the third electrode, and transmitting the lead signals from the case to the remote communication device by ultrasound.

[0078] Aspects of the present disclosure also provide an electrocardiogram (ECG) detection device for use with a wireless remote communication device. The device may comprise a case configured to fit over and conform to the remote communication device. The case may have an outer back surface, at least two outer side surfaces perpendicular to the back surface, and a front region through which the screen of the remote communication device held within the case can be viewed. The device may further comprise a first electrode on or adjacent to one of the at least two outer side surfaces, a second electrode on the outer back surface having an outer contact surface, and a third electrode on the outer back surface having an outer contact surface. The outer contact surfaces of the second and third electrodes may be recessed with respect to at least a portion of the outer back surface such that when the case is placed on a table surface with the outer back surface facing the table surface, the outer contact surfaces of the second and third electrodes do not contact the table surface. Further, the second and third electrodes may be arranged such that a patient can touch the outer contact surface of the second electrode with only the left hand and the outer contact surface of the third electrode with only the right hand, and can view the screen of the remote communication device held within the case while holding the first electrode against a leg.

[0079] The second and third electrodes may be entirely on the outer back surface. The first electrode may be entirely disposed on one of the at least two outer side surfaces. The first electrode may be on the outer back surface immediately adjacent to one of the at least two outer side surfaces. The first electrode may extend over the edge between the outer back surface and one of the outer side surfaces. Each of the outer side surfaces may be rectangular, and the first electrode may be centered between the two short sides of one of the outer side surfaces and may have a major axis extending in the direction of the long side of one of the outer side surfaces. The first electrode may extend over or near the length of one of the outer side surfaces for more than half of the length of the outer side surface. The second and third electrodes may be symmetrically arranged with respect to each other from the center of the outer back surface. The second and third electrodes may be part of an electrode unit that fits within an opening in the outer back surface of the case. The first electrode may have a surface area approximately the same as the surface area of the second or third electrode.

[0080] The device may comprise only three electrodes on the outer surface of the case. The outer back of the case may comprise one or more spacers configured to extend a portion of the outer back relative to the outer contact surfaces of the first and second surfaces such that the outer contact surface is recessed relative to the outer surface of the one or more spacers.

[0081] The device may further comprise an ultrasonic transmitter configured to transmit the signals detected from the first, second, and third electrodes to a wireless remote communication device by ultrasound.

[0082] Aspects of the present disclosure also provide an electrocardiogram (ECG) detection device for use with a wireless remote communication device. The device may comprise a case configured to fit over and conform to the remote communication device. The case may have an outer back, at least two outer sides perpendicular to the back, and a front region through which the screen of the remote communication device held within the case can be viewed. The device may further comprise a first electrode on or adjacent to one of the at least two outer sides, a second electrode on the outer back having an outer contact surface, a third electrode on the outer back having an outer contact surface, and an ultrasonic transmitter configured to wirelessly (e.g., by ultrasound) transmit the signals detected from the first, second, and third electrodes to the wireless remote communication device. The outer contact surfaces of the second and third electrodes may be recessed relative to at least a portion of the outer back such that the outer contact surfaces of the second and third electrodes do not contact the table surface when the case is placed on the table surface with the outer back facing the table surface.

[0083] Aspects of the present disclosure also provide a method for generating an electrocardiogram (ECG) from a patient using a handheld wireless remote communication device case having three electrodes on an outer surface of the case. The patient may be instructed to hold a first electrode extending along a side of the case against a leg while simultaneously touching a second electrode on a back of the case with a right hand and a third electrode on the back of the case with a left hand so as not to contact more than three electrodes on the case. A first lead signal (Lead I) of the ECG may be detected between the third electrode and the second electrode. A second lead signal (Lead II) of the ECG may be detected between the second electrode and the first electrode. A third lead signal (Lead III) of the ECG may be detected between the first electrode and the third electrode.

[0084] Aspects of the present disclosure also provide a method for generating an electrocardiogram (ECG) from a patient using a handheld wireless remote communication device case having three electrodes on an outer surface of the case. The patient may be instructed to hold the first electrode of the case against a leg while simultaneously touching the second electrode with a right hand and the third electrode with a left hand so as not to contact more than three electrodes on the case. A first lead signal (Lead I) of the ECG may be detected between the third electrode and the second electrode. A second lead signal (Lead II) of the ECG may be detected between the second electrode and the first electrode. A third lead signal (Lead III) of the ECG may be detected between the first electrode and the third electrode. The lead signals may be wirelessly (e.g., by ultrasonic) transmitted from the case to a remote communication device.

[0085] Also described herein is a wearable wristlet device that can reliably and conveniently transmit information (e.g., ECG information) recorded from a user using ultrasonic waves. Also described is an observation station including control logic for configuring and operating a mobile computing / remote communication device as an observation station capable of securely and reliably receiving such ultrasonic data.

[0086] Generally, devices, systems, and methods are described herein for ultrasonically transmitting digital and / or analog data from (and optionally to) a wearable (e.g., a wristlet) device having one or more sensors, a microprocessor, and a transducer capable of delivering ultrasonic frequencies (i.e., a piezoelectric speaker). The digitally transmitted data may be received by a receiving device having a microphone, such as a remote communication device (e.g., a telephone such as a personal remote communication device, iPhone®, DROID, or other smartphone, iPad® or other personal computer, PDA, etc.), where the microphone is capable of receiving audio in an ultrasonic frequency range (e.g., higher than 17 kHz, higher than 18 kHz, between about 16 kHz and about 22 kHz, between about 17 kHz and about 30 kHz, between about 18 kHz and 32 kHz, between about 17 kHz and 42 kHz, etc.). The digital information to be transmitted may be encoded and / or encrypted as described in more detail below. Additionally, the information may be compressed (data compression) prior to encryption.

[0087] Both unidirectional communication (e.g., from the wristlet to the device) and bidirectional communication are contemplated, including various methods for performing simple bidirectional communication between the wearable device and an observation station (e.g., a smartphone).

[0088] Also described herein are an ultrasonic digital modem and the protocol and logic of the digital modem for securely transmitting digital information ultrasonically from a wearable device, such as a wristlet, to a remote communication device configured as a receiver.

[0089] A wristlet device including one or more sensors for detecting activity information and / or health information about a wearer, including a microcontroller configured as an ultrasonic modem, is described herein. In some variations, the microcontroller includes logic (e.g., hardware, software, firmware, or some combination thereof) that enables the device to drive ultrasonic transmission of data from a speaker (e.g., a piezoelectric speaker element). Also described is a method of configuring or adapting the microcontroller to operate as an ultrasonic modem. For example, in some variations, the microcontroller can be programmed to operate as an ultrasonic modem. The ultrasonic modem can be configured to format the information to be transmitted as a hybrid digital and analog format. In some variations, the ultrasonic modem can be an ultrasonic modem component that encrypts information using an encryption key.

[0090] A receiver configured to receive ultrasonic digital data acoustically transmitted by an ultrasonic digital modem is also described herein. Generally, a remote communication device (e.g., a smartphone) can be configured to operate as a receiver for receiving ultrasonic digital data. Thus, the remote communication device can include hardware, software, and / or firmware configured to receive, decrypt, interpret, display, analyze, store, and / or transmit data transmitted by ultrasonic transmission from a digital ultrasonic modem. In some variations, logic (e.g., client software and / or firmware, an application, etc.) can be executed on the remote communication device such that the remote communication device can operate as a receiver for digital ultrasonic data. Thus, a device including executable logic for receiving and interpreting (e.g., decrypting) data transmitted by a digital ultrasonic modem and executable logic for receiving and interpreting (e.g., decrypting) data transmitted by a digital ultrasonic modem executable logic is described herein.

[0091] Specific devices and systems configured to include a digital ultrasonic modem are further described herein. Any of these devices may include a source of digital information (e.g., a medical sensor or device (e.g., a thermometer, a pulse oximeter, etc.), an audio transducer (e.g., a speaker capable of emitting ultrasonic signals), and a controller (e.g., a microcontroller) configured to encode digital information from the source of digital information as an ultrasonic signal to be transmitted by the audio transducer). In some variations, the audio transducer is configured to emit both audible (e.g., lower than ultrasonic) sounds (e.g., for emitting a buzzer sound or a beep sound within the normal human audible range) as well as ultrasonic frequencies (e.g., higher than 17 kHz).

[0092] In one example, it is described herein that the Texas Instruments AFE4110 digital thermometer is modified as described to encode body temperature data and transmit it via ultrasound to a remote communication device (e.g., a smartphone) located at a distance from the thermometer. The device's microcontroller (a Texas Instruments MSP430 type controller) is configured to include an ultrasonic modem for transmitting ultrasonic digital data by encoding the data signal (via a microprocessor) for transmission with a connected piezoelectric speaker. The speaker may be the same speaker built into the thermometer and may be used to inform the user (e.g., within the normal human audible range) of a stable body temperature with a sound. Thus, the thermometer can be modified to include a very low-cost digital ultrasonic modem by executing the control logic in the microcontroller to process data from the thermometer and transmit a signal encoded with the piezoelectric speaker in the ultrasonic frequency range (e.g., >17 kHz). The thermometer may include a security key (e.g., a barcode, QR code (registered trademark), etc.) printed on the outside of the device that can be read by a receiving remote communication device (e.g., a smartphone).

[0093] For example, in some variations, a system is described herein that includes a medical sensing device and a device that uses ultrasound to digitally transmit biological parameters received by the medical sensing device to one or more remote communication devices (e.g., a smartphone) where further processing and / or transmission of the information can occur. The executable logic can also be referred to as an adapter for adapting the medical sensing device so that the medical sensing device can transmit biological parameter information to the remote communication device via ultrasound for further processing. Systems and / or subsystems for use with the remote communication device are also described so that the remote communication device can receive and convert an ultrasonic-encoded health metrics information signal. These subsystems can include client software (e.g., an application) that is to be executed on the remote communication device (e.g., a phone) to convert the ultrasonic health information (or biological parameter) signal into a digital signal that can be uploaded, stored, and / or analyzed by the remote communication device.

[0094] A medical sensing device can be any device for receiving biological parameters such as a patient's vital signs. Biological parameters may also be referred to as biometric data. For example, a medical sensing device can be a thermometer, a blood pressure transducer, a glucose monitor, a pulse oximeter, a heart rate meter, a pedometer, an activity monitor, a hydration monitor, etc. The medical sensing devices or systems referred to herein are usually digital systems since they can display a numerical (e.g., digital) representation of biological parameters. For example, a device can convert an analog biological parameter (e.g., body temperature, blood glucose, blood pressure, or any other health metrics information) into a digital signal that can be displayed to a user or otherwise presented. For example, a medical sensing system can include a digital thermometer for measuring a subject's body temperature, a cuff for presenting a patient's blood pressure, a glucose (blood sugar) monitor, a pulse oximeter, etc., including combinations of these devices. Of particular interest are home medical sensing systems or devices, especially those having sensors for observing or collecting biological parameters from a patient and presenting the information on a display.

[0095] As will be described in more detail below, in some variations, the devices and systems format and / or encode information such that the information includes a hybrid of both digital (e.g., extracted and / or alphanumeric) information and analog (e.g., graphical) information. As used herein, the term "analog" refers to information that can be graphically displayed to show changes or trends arranged in sequence. Analog information can refer to a variable physical level that is quantified (e.g., a variable that changes over time). The actual information can be digital (e.g., by converting from continuous values to discrete values), but it may still be referred to herein as "analog" because it represents the change, distance, or some other variation of one or more parameters over time.

[0096] Any information transmitted as an ultrasonic signal (e.g., analog, digital, hybrid digital / analog, etc.) can be encrypted. For example, the information can be encrypted using an encryption key. The encryption key can be displayed on the device that transmits the ultrasonic signal, or alternatively, made available on or by the device. Generally, the encryption key may be input into a certain remote communication device, whereby that particular device may then be paired with a device including an ultrasonic modem and receive and decrypt the information. Encryption of the data can enable protection of information that requires care in handling by the patient. Encryption can also reduce system noise as it can limit the signals received to those that are properly encoded.

[0097] As used herein, biological parameters or information can include any patient information processed, sensed, and / or calculated by a medical sensing system, particularly digitally encoded biological parameters. For example, biological parameters can include body temperature, blood pressure, blood glucose level, pH, oxygen saturation, heart rate, respiratory rate, or any other biological measurement, particularly those related to cases including diagnosis and health monitoring.

[0098] As used herein, a remote communication device includes a smartphone (e.g., iPhone (registered trademark), droid (registered trademark), or other personal communication device), a tablet computer (e.g., iPad (registered trademark), tablet PC, etc.), and / or a desktop computer that includes (or can be adapted to include) a microphone capable of receiving ultrasonic sound. The remote communication device can include logic for converting an ultrasonic sound into a digital signal that can be displayed, uploaded / transmitted, stored, and / or analyzed.

[0099] Accordingly, in some variations, a medical sensing device for transmitting digital biological parameters via ultrasound is described herein. In some variations, the device can include a sensor for detecting biological parameters from a patient, a processing device for encoding a digital representation of the biological parameters as an ultrasonic audio signal, and an ultrasonic transducer for transmitting the ultrasonic audio signal from the processing device.

[0100] For example, the sensor can be a transducer (such as a body temperature sensor, a pressure sensor, etc.) for converting biological parameters. The device can also include a controller (such as a microcontroller) for processing signals from the sensor. The processing device may include a signal generator for generating a signal from the detected and / or processed patient biological parameter information, and the signal may be encoded for transmission. The signal may be encoded as digital packets (such as words, bytes, etc.). For example, the signal may include a start bit, a stop bit, information bits (such as a packet identifier) for identifying the type or source of the biological parameter, a digital representation of the biological parameter, and in some variations, a cyclic redundancy check (CRC) portion. In some variations, the signal (including the biometric measurement or data portion) may have a timestamp and / or a date stamp.

[0101] As mentioned, in some variations, the system can be configured to encrypt information and transmit only the encrypted information. The remote communication device can be configured to directly receive an encryption key (such as by capturing and / or analyzing a number that describes the encryption key).

[0102] In some variations, the system or device may be configured such that measurements are taken at time x, stored in a device (e.g., a thermometer, a blood glucose meter, etc.), and later transmitted via ultrasound to a remote communication device (e.g., a smartphone or tablet) and ultimately uploaded (e.g., to the cloud). In some variations, some timestamp / date-stamped measurement results may be recorded in the device and transmitted in a burst together to the remote communication device. As will be described in more detail below, the device may in some variations be primarily unidirectional (e.g., sending data from a biometric device to a remote communication device), and the device may be configured to receive at least an acknowledgement signal and / or indicator that it is near the remote communication device. In some variations, the ultrasound transducer may also be configured to receive an acknowledgement signal from the remote communication device. The acknowledgement may indicate that the remote communication device has received the transmitted message (data), or that the remote communication device is ready to receive data transmitted to it, or both.

[0103] The ultrasound transducer can be any suitable transducer including a piezoelectric crystal transducer.

[0104] In some variations, a system for transmitting digital biological parameters via ultrasound includes a medical sensing device having a sensor for detecting a biological parameter, a processing device for encoding a digital representation of the biological parameter as an ultrasonic audio signal, and an ultrasound transducer for transmitting the ultrasonic audio signal, and client control logic executed by a remote communication device and configured to receive the ultrasonic audio signal and convert it back to a digital representation of the biological parameter.

[0105] The processing device may convert some or all of the digital biological parameter signal (typically numerical) into an ultrasonic signal by use of any suitable signal processing technique including, but not limited to, frequency shift keying.

[0106] The client control logic, which can be software, hardware, firmware, etc., can also be referred to as software or a client application. The client control logic can be executed on a remote communication device. The client control logic can also include components for passing a digital representation of biological parameters to other devices, for example, uploading it to, for example, a website or a server. In some variations, the client control logic can be configured to locally display or otherwise present information on the remote communication device.

[0107] A system for transmitting digital health parameters is also described herein. The system includes an ultrasonic transducer capable of transmitting signals in an outdoor environment at a frequency higher than about 17 kHz (for example, centered around 19 kHz or 20 kHz), and a signal generator configured to generate an ultrasonic signal corresponding to a digital representation of biological parameters. The identifier is associated with at least one frequency higher than about 17 kHz (for example, centered around 19 kHz or 20 kHz).

[0108] As an example, a digital thermometer for ultrasonically transmitting digital temperature information to a remote communication device for further processing and transmission is described herein. The digital thermometer can include a temperature sensor for detecting a patient's body temperature, a signal generator for generating a signal corresponding to the digital representation of the patient's body temperature, and an ultrasonic transducer for transmitting the digital representation of the patient's body temperature as an ultrasonic signal having one or more frequencies higher than 19 kHz. The thermometer can include a cryptographic key on the outside of the thermometer that can be photographed and / or viewed by a remote communication device configured to receive the ultrasonic signal.

[0109] In general, a digital ultrasonic modem device for securely transmitting digital data via ultrasonic waves is described herein. Such a device may include a microprocessor, an ultrasonic transducer, an encryption key located on the device, and ultrasonic transmission logic that constructs digital data for acoustic transmission by the ultrasonic transducer at a frequency of 17 kHz or higher, and the ultrasonic transmission logic is further configured to encrypt the digital data according to the encryption key.

[0110] Any suitable ultrasonic transducer may be used. For example, the ultrasonic transducer may be a piezoelectric speaker. As mentioned, the encryption key may be visibly marked on the device and may be configured as an alphanumeric code, symbol, etc. For example, the encryption key may be configured as a barcode, a QR code (registered trademark), etc.

[0111] Any of the systems described herein may be configured as a system for secure ultrasonic transmission of data, including an ultrasonic communication device with an ultrasonic transducer, an encryption key located on the ultrasonic communication device, and an ultrasonic communication device with ultrasonic transmission logic that constructs digital data for acoustic transmission by the ultrasonic transducer at a frequency of 17 kHz or higher, wherein the ultrasonic transmission logic is further configured to encrypt the digital data according to the encryption key, and may include a remote communication device with decryption logic executable thereon, the remote communication device comprising a receiver for receiving ultrasonic signals from the ultrasonic communication device, and the decryption logic being configured to receive the encryption key and apply the encryption key to decrypt the ultrasonic signal.

[0112] In general, the encryption key may be visible on the ultrasonic communication device, the packaging of the device, etc.

[0113] In any of these variations described herein, the remote communication device may include an input for entering an encryption key, which may provide the information to the decryption logic. For example, the input may be a camera for taking an image of an encryption key (e.g., a barcode, a QR code (registered trademark), etc.), and the encryption key may be determined from the image. In some variations, the input comprises a manual input (e.g., a keypad, a touch screen, etc.) for manually entering the encryption key.

[0114] Methods for securely transmitting information using ultrasonic waves are also described herein. For example, in some variations, the method includes receiving an encryption key present on the outer surface of an ultrasonic communication device, receiving an encrypted ultrasonic signal from the ultrasonic communication device, and decrypting the ultrasonic signal with the encryption key.

[0115] In some variations, the step of receiving the encryption key comprises obtaining the encryption key from the outer surface of the ultrasonic communication device. The step of decrypting the ultrasonic signal may include decrypting the ultrasonic signal at a remote communication device. As mentioned, the step of receiving the encryption key may comprise taking an image of the encryption key using a camera of the remote communication device.

[0116] Generally, any of the systems described herein may use hybrid digital and analog encoding. For example, a device for transmitting both digital and analog ultrasonic data (hybrid digital and analog data) may include a microprocessor, an ultrasonic transducer, and hybrid transmission logic configured to generate a signal comprising digital data added to analog data for acoustic transmission by the ultrasonic transducer at a frequency of 17 kHz or higher.

[0117] As mentioned above, the information can be encoded using frequency shift keying (FSK). FSK digital data can be added to analog data that is not encoded by FSK but is frequency modulated to form a hybrid digital / analog signal.

[0118] In any of these variations, the device can include a sensor for detecting biological parameters from a patient and / or a microprocessor configured to extract digital data from analog data. In some variations, the digital data comprises calibration data for the analog data (e.g., minimum value, maximum value, variable interval (e.g., time interval), scale, etc.). The analog data can comprise any suitable signal typically measured from a device sensor such as an EEG, a subject's body temperature over time, a subject's glucose level over time, a subject's blood pressure over time, a subject's oxygen level over time, or a subject's physical activity over time.

[0119] A method of transmitting hybrid digital and analog signals using ultrasound is also described herein. For example, the method can include generating an ultrasonic signal comprising digital data encoded using frequency shift keying (FSK) that is added to an analog signal comprising a frequency modulated signal modulated at a frequency higher than 17 kHz, and acoustically transmitting the signal using an ultrasonic transducer.

[0120] The method can also include detecting biological parameters from a patient, where the analog signal comprises the biological parameters. The method can also include extracting digital data from the analog signal. The analog signal can comprise an EEG, a subject's body temperature over time, a subject's glucose level over time, a subject's blood pressure over time, a subject's oxygen level over time, or a subject's physical activity over time.

[0121] In some variations, the method also includes receiving an ultrasonic signal on a remote communication device having an ultrasonic audio pickup.

[0122] In any of the variations described herein, the ultrasonic signal can be stored prior to transmission. Any of the variations described herein can be encoded using an error correction code. The method may also include the step of retransmitting the ultrasonic signal, the signal may be retransmitted a fixed number of times, or the signal may be retransmitted continuously. In some variations, two-way communication can be used between an ultrasonic communication device and a remote communication device including executable logic for receiving and / or decoding ultrasonic signals. Thus, in some variations, the remote communication device can be configured to return a signal to the ultrasonic communication device. The ultrasonic communication device may include a receiver, or may be adapted to receive a signal with a transmitter (e.g., a piezoelectric element).

[0123] An ECG detection wristlet configured to transmit ECG information to a mobile remote communication device or multiple devices is also described herein.

[0124] For example, a wireless wearable wristlet device for acquiring an electrocardiogram (ECG) signal from a subject wearing such a device and transmitting this information ultrasonically to a mobile remote communication device is described herein. The wristlet device can include a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, an ultrasonic transducer, and a processing device coupled to the ultrasonic transducer and configured to receive an ECG signal from the two or more electrodes and encode the signal to be transmitted as an ultrasonic signal for transmission by the ultrasonic transducer at a frequency higher than about 17 kHz.

[0125] The wristlet body can be configured as a strap (e.g., a strap of any type of watch), a band, a bracelet, etc. In some variations, the wristlet includes a "front" region that can be worn on the subject's wrist in an upward-facing orientation. The wristlet can include a pair of electrodes (or more than two electrodes). For example, in some variations, the wristlet includes an inner electrode that faces the wearer's wrist when the wristlet is worn, so the inner electrode can reliably contact the wearer's skin when worn. The second electrode can be disposed on the front or side of the wristlet. This second electrode can be configured to allow the wearer to touch the wristlet with the opposite hand / arm. In some variations, a third electrode can be disposed on the wristlet. For example, the third electrode can be on the side of the wristlet and can be configured to allow the subject to touch the third electrode with another part of the body (e.g., the chest, leg, etc.).

[0126] The processing device can be configured to encode a signal to be transmitted as an ultrasonic signal for transmission by an ultrasonic transducer at a frequency between about 17 kHz and about 30 kHz (or any of the other ranges defined herein, including higher than 16 kHz, higher than 17 kHz, higher than 18 kHz, etc.). Generally, the processing device can be configured to encode a signal to be transmitted as a hybrid signal comprising digital information added to an analog signal.

[0127] The device may also be configured to receive a signal (e.g., an ultrasonic signal) including an ultrasonic signal from a mobile remote communication device. In some variations, the device further comprises an ultrasonic receiver configured to receive an ultrasonic signal from the mobile remote communication device. This may also create a pairing of information (e.g., for synchronization, confirmation of information transmission, etc.) between the devices. Separate receiving ultrasonic transducers may be used, or the same ultrasonic transducer may be configured to perform both transmission and reception. For example, the ultrasonic transducer may be configured to transmit a signal from the processing device as an ultrasonic signal and receive an ultrasonic signal (e.g., from a mobile remote communication device).

[0128] In some variations, the devices (listers) described herein may be configured to operate at extremely low power. As mentioned above, the device may include a battery having a voltage of less than 1.8V.

[0129] Generally, the devices described herein may generally be configured to operate in real time. Specifically, ECG information may be received and transmitted in real time. The mobile remote communication device may display (and / or retransmit) in real time. For example, the processing device may be configured to transmit an encoded ECG signal in real time.

[0130] Generally, any of the lister devices may be configured without a display or output, or with only an audible output (e.g., beep, tone), or with only an LED (e.g., simple indicator light). Instead, the device may rely on communication with a base station such as a mobile remote communication device to display and, in some cases, analyze the signal. For example, the device may include an indicator indicating when it is communicating with the mobile remote communication device. Thus, a lister device without a display for displaying ECG information may make the device smaller, lighter, and less expensive to manufacture and operate.

[0131] Furthermore, in some variations, the device may be configured to store most of the data, such as ECG data, and transmit it when a receiver, such as a mobile phone, is ready to receive it. Thus, any of these variations may add additional information, such as a timestamp / date stamp, user input data, etc. Thus, in some variations, the device further comprises a memory coupled to the processing device and configured to store the signals encoded for later transmission.

[0132] In some variations, as discussed above, the processing device is configured to encode the signals to be transmitted as digital signals.

[0133] Generally, the device (e.g., the processing device) may also be configured to determine when a mobile remote communication device receives the encoded signals from the device.

[0134] The wristlet device described herein may also be configured as a watch and may include a watch face, etc.

[0135] Also described herein is a wireless wearable wristlet device for detecting an electrocardiogram (ECG) signal from a subject wearing the device and transmitting this information to a mobile remote communication device via ultrasound. The wristlet device comprises a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, an ultrasonic transducer, and a processing device coupled to the ultrasonic transducer and configured to receive the ECG signal from the two or more electrodes and encode the signal to be transmitted as a hybrid ultrasonic signal comprising digital information added to an analog representation of the ECG signal for transmission by the ultrasonic transducer at a frequency above about 17 kHz.

[0136] As described herein, a hybrid ultrasonic signal can be configured to encode digital information using frequency shift keying (FSK) and add the FSK digital signal to an analog signal that is not encoded by FSK but is frequency modulated. For example, a processing device can be configured to extract digital information from an ECG signal. In some variations, the digital information comprises calibration data for the analog signal. The processing device can be configured to encode a signal to be transmitted as an ultrasonic signal for transmission by an ultrasonic transducer at any suitable ultrasonic frequency (e.g., a frequency above the normal audible range), such as those described herein, e.g., a frequency between about 17 kHz and about 30 kHz.

[0137] In any of these device variations, the device can be configured to perform both transmission and reception of the ultrasonic signal. For example, the device can include an ultrasonic receiver configured to receive an ultrasonic signal from a mobile remote communication device. In some variations, the same transducer used to transmit an ultrasonic signal (e.g., an ECG signal) can also be configured to receive the ultrasonic signal (e.g., be ready to receive requests for transmission, confirmations of transmission, requests for retransmission, etc.). The ultrasonic transducer can be configured to transmit a signal from the processing device as an ultrasonic signal and receive an ultrasonic signal from the mobile remote communication device.

[0138] A wireless wearable wristlet device for detecting an electrocardiogram (ECG) signal from a subject wearing the device and transmitting this information to a mobile remote communication device by ultrasonic waves is also described herein. The wristlet device includes a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, an ultrasonic transducer configured to transmit and receive ultrasonic signals, and a processing device coupled to the ultrasonic transducer and configured to receive the ECG signal from the two or more electrodes and encode a signal to be transmitted as an ultrasonic signal for transmission by the ultrasonic transducer at a frequency above about 17 kHz. Further, the processing device is configured to receive an ultrasonic signal from the mobile remote communication device.

[0139] Aspects of the present disclosure also provide a wireless wearable wristlet device for detecting an electrocardiogram (ECG) signal from a subject wearing the device and wirelessly (e.g., by ultrasonic waves) transmitting this information to a mobile remote communication device. The wristlet device can include a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, a wireless (e.g., ultrasonic) transducer, and a processing device. The processing device may be coupled to the wireless transducer and may be configured to receive the ECG signal from the two or more electrodes and encode a signal to be transmitted as a wireless signal (e.g., an ultrasonic signal for transmission by the ultrasonic transducer at a frequency above about 17 kHz).

[0140] The processing device can be configured to encode a signal to be transmitted as an ultrasonic signal for transmission by an ultrasonic transducer at a frequency between about 17 kHz and about 30 kHz. The processing device can be configured to encode a signal to be transmitted as a hybrid signal comprising digital information added to an analog signal. The device can further comprise an ultrasonic receiver configured to receive an ultrasonic signal from a mobile remote communication device. The ultrasonic transducer can be configured to transmit a signal from the processing device as an ultrasonic signal and to receive an ultrasonic signal from a mobile remote communication device.

[0141] The device can further comprise a battery having a voltage less than 1.8. The processing device can be configured to transmit an encoded ECG signal in real time. The device can further comprise a memory coupled to the processing device and configured to store an encoded signal for later transmission. The processing device can be configured to encode a signal to be transmitted as a digital signal. The device can further comprise an indicator indicating when the device is communicating with a mobile remote communication device. The processing device can further be configured to determine when the mobile remote communication device has received an encoded signal from the device. The device can be configured as a clock.

[0142] Aspects of the present disclosure also provide a wireless wearable wristlet device for detecting an electrocardiogram (ECG) signal from a subject wearing the device and wirelessly (e.g., via ultrasound) transmitting this information to a mobile remote communication device. The wristlet device includes a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, a wireless (ultrasound) transducer, and a processing device. The processing device is coupled to the wireless (e.g., ultrasound) transducer and is configured to receive the ECG signal from the two or more electrodes and encode a signal to be transmitted as a hybrid wireless (e.g., ultrasound) signal that includes digital information added to an analog representation of the ECG signal for transmission. The ultrasound transducer may transmit signals at frequencies above about 17 kHz.

[0143] The hybrid ultrasound signal may be configured to encode digital information using frequency shift keying (FSK) and add the FSK digital signal to an analog signal that is frequency modulated but not encoded by FSK. The processing device may be configured to extract digital information from the ECG signal. The digital information may include calibration data for the analog signal. The processing device may be configured to encode a signal to be transmitted as an ultrasound signal for transmission by the ultrasound transducer at a frequency between about 17 kHz and about 30 kHz. The ultrasound receiver may be configured to receive an ultrasound signal from the mobile remote communication device. The ultrasound transducer may be configured to transmit a signal from the processing device as an ultrasound signal and receive an ultrasound signal from the mobile remote communication device.

[0144] The device may further comprise a battery having a voltage of less than 1.8V. The processing device may be configured to transmit the encoded signal in real time. The device may further comprise a memory coupled to the processing device and configured to store the encoded signal for later transmission. The processing device may be configured to encode a signal to be transmitted as a digital signal. The device may further comprise an indicator indicating when the device is communicating with a mobile remote communication device. The processing device may further be configured to determine when the mobile remote communication device has received the encoded signal from the device. The device may be configured as a clock.

[0145] Aspects of the present disclosure also provide a wireless wearable wristlet device for detecting an electrocardiogram (ECG) signal from a subject wearing the device and wirelessly (e.g., via ultrasound) transmitting this information to a mobile remote communication device. The wristlet device may comprise a wristlet body configured to fit around the wrist, two or more electrodes for detecting an ECG signal from the subject, a wireless (e.g., ultrasound) transducer configured to transmit and receive ultrasound signals, and a processing device coupled to the wireless (e.g., ultrasound) transducer and configured to receive the ECG signal from the two or more electrodes and encode a signal to be transmitted as a wireless (e.g., ultrasound) signal for wireless (e.g., ultrasound) transmission. The ultrasound transducer may transmit signals at a frequency above about 17 kHz. The processing device may be configured to receive an ultrasound signal from the mobile remote communication device.

[0146] The wearable computing device may also be in the form of a wristlet or an armband. Aspects of the present disclosure also provide an external housing or cover for a computing device worn on the wrist or arm. The external housing or cover may include two or more electrodes for detecting an ECG signal from a subject and a wireless transmitter for transmitting the ECG signal to a computing device worn on the wrist or arm.

[0147] FIG. 1 shows a schematic diagram of a system 1000 for measuring and observing one or more biometric parameters or physiological parameters of a user US. The system 1000 may include a computing device 1100 and an external sensor device 1200 configured to be coupled to or removably attached to the computing device 1100. The computing device 1100 may include one or more of a personal computer, a laptop computer, a tablet computer (such as an Apple iPad®, an Apple iPod®, a Google Nexus tablet, a Samsung Galaxy tablet, a Microsoft Surface, etc.), a personal digital assistant (PDA), a smartphone (such as an Apple iPhone®, a Google Nexus phone, a Samsung Galaxy smartphone, etc.), or a wearable computing device (such as Google Glass, a Samsung Galaxy Gear Smart Watch, etc.). In many embodiments, the computing device includes a tablet computer or a smartphone. The external sensor device 1200 may be configured to be removably coupled to the computing device 1100 and may include a cover for covering the computing device, such as a tablet computer case or a smartphone case or cover. In this way, when the user US replaces or upgrades their computing device 1100, it may not be necessary to replace the external sensor device 1200. That is, the user may use the same external sensor device 1200 with various computing devices 1100 that the user may own.

[0148] The computing device 1100 may include a processing device 1110, a memory unit 1120 such as a RAM module, a data storage unit 1130 (e.g., a flash memory module, a hard drive, a ROM, etc.), a network interface 1140 configured to connect to a cellular data network (e.g., using GSM, GSM plus EDGE, CDMA, quadband, or other cellular protocols), or a WiFi (e.g., 802.11 protocol) network, a local interface 1150, an operating system 1160 stored in the data storage unit 1130, loaded into the memory unit 1120, and executable by the processing device 1110, a first application 1170 such as a first mobile software application (a "mobile app") downloaded from an online application distribution platform, a second application 1180 such as a second mobile software application (a "mobile app") downloaded from an online application distribution platform, and a user interface 1190. For example, the online application distribution platform may be the Apple App Store, Google Play, Windows Phone Store, BlackBerry App World, etc. The operating system 1160 may include instructions for operating the computing device 1100. The user interface 1190 may include a display 1195 for displaying one or more components of the operating system 1160, the first application 1170, or the second application 1180. For example, the display 1195 may be a touch screen display for operating and controlling the operating system 1160, the first application 1170, or the second application 1180. One or more of these elements may be combined or omitted.The computing device 1100 may further include other components such as a motion detection component, one or more cameras, additional displays, a power supply, a fan, and various I / O ports.

[0149] The external device 1200 may include a sensor 1210, a processing device 1220, and a local interface 1230. The sensor 1210 is configured to couple with the user US through a connection 1215, physical contact, for example, to detect or sense one or more physiological parameters of the user US. Generally, the one or more physiological parameters include cardiac parameters such as the user's heart rate, heart rate variability, blood pressure, blood pressure variability, arrhythmia, vibrocardiogram (SCG), SCG parameters, electrocardiogram (ECG), or ECG parameters. Other physiological parameters are contemplated. For example, the sensor 1210 may include an activity sensor, a blood glucose sensor, a blood oxygen concentration sensor, a thermometer, a respiration sensor, a metabolism sensor, an odor detector, etc. The processing device 1220 may receive the detected physiological parameter and process it into a signal for the local interface 1230 to be transmitted to the local interface 1150 of the computing device 1100 through a connection 1235. The connection 1235 may include a wired connection such as a USB connection, a Firewire connection, a Lightning connection, etc. Alternatively, or in combination, the connection 1235 may include a wireless connection such as a WiFi connection, a Bluetooth connection, a low power Bluetooth connection, an NFC (near field communication) connection, a near field ultrasonic communication connection, etc., as described in U.S. Patent Nos. 8,301,232 and 8,509,882.

[0150] The first application 1170 may be stored in the storage 1130 of the computing device 1100, loaded into the memory 1120 of the computing device 1100, and executed using the processing device 1110 and the operating system 1160. The processing device 1110 may be coupled to the local interface 1150 of the computing device 1100 to receive detected physiological parameters under the instructions from the first application 1170. Further, the processing device 1110 may store the received physiological parameters in one or more of the memory 1120 or the storage 1130 of the computing device under the instructions from the first application 1170. The stored physiological parameters may be time-stamped and tagged with user identification information for later access and analysis. The processing device 1100 may also cause the physiological parameters to be displayed on the display 1195 of the user interface under the instructions from the first application 1170. For example, the physiological parameters may be displayed in real time as they are measured. The first application 1170 may also include an algorithm executed by the processing device 1100 to analyze the physiological data and may present the interpretation and analysis to the user US. For example, if an arrhythmia is detected, the processing device 1100 may issue a warning to the user US or, via the network interface 1140, to a remote healthcare provider such as a physician, nurse, or hospital under the instructions from the first application 1170. Further, the processing device may be configured to automatically transmit the physiological data via the network interface 1140 to a remote computing device, a remote server, or a remote healthcare provider such as a physician, nurse, or hospital under the instructions from the first application 1170.

[0151] In some embodiments, the processing device 1110 may use the measured physiological parameters to identify or authenticate the user and perform operations based on the user's identification information under the instructions from the first application 1170 or other applications. For example, the user may be authenticated based on the characteristics of the user's heartbeat. The duration of a particular portion of the user's heart rhythm, the relative sizes of the peaks of the user's electrocardiogram (ECG), or other related amplitudes or amplitude ratios may be processed and compared with a profile stored for authenticating the user. The processing device 1100 may be used to generate a reference profile under the instructions from the first application 1170 or other applications. In some embodiments, the processing device 1100 may use the measured physiological parameters to determine the user's mood and provide related data under the instructions from the first application 1170 or other applications.

[0152] For example, the electrical activity of the heart of user US can be detected and analyzed. A typical heartbeat may include several potential variations that can be classified into waves and complexes, including P waves, QRS complexes, T waves, and possibly U waves as known in the art. The shape and duration of the P wave may be related to the size of the user's atria (e.g., indicating atrial enlargement) and may be a first source of information about the user's unique heartbeat characteristics.

[0153] The QRS complex may correspond to ventricular depolarization and can be separated into three distinct waves: the Q wave, the R wave, and the S wave. Since the ventricles contain more muscle than the atria, the QRS complex is larger than the P wave. Also, due to the heart's His / Purkinje system, which can increase the conduction velocity to coordinate ventricular depolarization, the QRS complex may appear "spiky" rather than rounded. The duration of the QRS complex in a healthy heart can range from 60 ms to 100 ms, but it can vary due to conduction abnormalities. The duration of the QRS complex can serve as another source of information about the user's unique heartbeat characteristics.

[0154] The duration, amplitude, and morphology of each of the Q wave, R wave, and S wave may vary from person to person, and specifically may vary greatly in users with heart disease or heart abnormalities. For example, a Q wave greater than one-third the height of the R wave, or a Q wave with a duration longer than 40 ms, may indicate a myocardial infarction and may provide characteristics unique to the user's heart. Similarly, other healthy ratios of the Q wave to the R wave can be used to distinguish the heartbeats of different users.

[0155] The electrical activity of the heart of user US may also include one or more characteristic durations or intervals that can be used to distinguish different users. For example, the electrical activity of the heart may include a PR interval and an ST segment as known in the art. The PR interval from the start of the P wave to the start of the QRS complex can be measured. The PR interval typically can last from 120 ms to 200 ms. A PR interval with a different duration may indicate one or more heart defects of the heart, such as a first-degree atrioventricular block (e.g., the PR interval lasts longer than 200 ms), pre-excitation syndrome via an accessory conduction pathway leading to early ventricular activity (e.g., the PR interval lasts less than 120 ms), or another type of atrioventricular block (e.g., variable PR interval). For example, the ST segment from the QRS complex to the T wave, starting at the intersection of the QRS complex and the ST segment and ending at the start of the T wave, can be measured. The ST segment typically may last from 80 ms to 120 ms and is usually slightly convex downward. The length of the ST segment and the combination of depressions or elevations of the ST segment can also be used to generate characteristic information unique to each user's heartbeat.

[0156] The T wave may represent ventricular repolarization or recovery. The interval from the start of the QRS complex to the peak of the T wave can be called the absolute refractory period. The last half of the T wave can be called the relative refractory period or vulnerable period. The amplitude of the T wave and the durations of the absolute refractory period and the relative refractory period can also be used to define the characteristics of the user's heart rate.

[0157] The QT interval, which can represent the total time required for the ventricles to depolarize and then repolarize from the beginning of the QRS complex to the end of the T wave, can be measured. The QT interval usually may last from 300 ms to 450 ms and may vary based on the user's heart rate conditions. Several correction factors have been developed to correct the QT interval of the heartbeat 222. Both the measured QT interval value and the corrected QT interval value can be used to define the unique characteristics of the user's heartbeat.

[0158] Since the heartbeat or heart rate of user US may vary slightly based on the activity or mood of user US, each approved user US can first provide the device with their basic or standard heart rate, heartbeat, or electrical activity before first use. The first application 1170 can be executed by the processing device 1110 to record this reference measurement value. For example, an external device or sensor 1200 can sample several heartbeats or electrical activities at several different times to detect variations in the electrical activity of user US's heart. This data can be sent to the computing device 1100. The processing device 1110 can then process the detected signal under the instructions from the first application 1170 to determine some unique characteristics of the activity of user US's heart and identify the appropriate range of characteristic values for each of the processed characteristics. Based on the characteristic values and the associated ranges, the processing device 1110 can select one, all, or a subset of the characteristics to define the unique heart activity profile of the approved user US. The specific combination of characteristics and the associated ranges may be selected to minimize overlap with other approved users, or may be based on characteristic values and ranges that are outside the range of a certain average value and average range (e.g., not using the characteristic values and ranges that an average user of the device would have).

[0159] System 1000 can be used to authenticate user US based on the measured electrical activity of user US's heart when compared with a generated profile. If the measured electrical activity matches the generated profile, processing device 1110 can authenticate user US under the instructions of operating system 1160, first application 1170, or other applications. Processing device 1110 can also be instructed to perform any appropriate actions in response to identifying and authenticating user US. In some embodiments, processing device 1110 can be instructed to provide access to restricted applications, such as applications that only a specific user has a license for, or applications that only a specific user has purchased. In some embodiments, processing device 1110 can be instructed to provide access to specific data or application settings associated with authorized user US. For example, processing device 1110 can be instructed to provide access to the contact list of identified user US, or the email account of identified user US, or the call history. As another example, processing device 1110 can be instructed to enable user US to access a private banking application or perform financial transactions (such as transferring funds to different accounts or purchasing goods) using an electronic device. In some embodiments, computing device 1100 can load the settings and profiles of user US to provide customized markings to the user. For example, computing device 1100 can display icons or options in a manner set by the user, or perform the display using a color scheme, font, or other customizable display attributes associated with the identified user.

[0160] In some embodiments, system 1000 can determine the mood of user US using the detected heart rate or heart rate characteristics. Specifically, since the acceptable determined characteristics associated with each user US can include a range of values, processing device 1110 can be instructed to determine the distribution of the detected characteristics within the acceptable characteristic range. Using the determined distribution, processing device 1110 can establish the mood of the user and provide to the electronic device an action or data (e.g., media) associated with the estimated mood.

[0161] In some embodiments, computing device 1100 can perform media playback based on the detected mood of user US or the heart signal. For example, computing device 1100 can identify media having a beats per minute or other characteristic associated with or related to the heart signal or heart rate of user US and play the identified media. As another example, the media provided can have a beats per minute faster or slower than the user's current heart rate to instruct the user to move more vigorously (e.g., during exercise), or to cool down or calm down (e.g., at the end of exercise).

[0162] Aspects of the present disclosure may also include a process for performing operations of a computing device based on signals of the heart of user US. In a first step, system 1000 may detect signals of the heart of user US. For example, the heart rate or heart beats of user US may be detected using sensor 1210 of external device 1200. External device 1200 may transmit the detected signals to computing device 1100 through connection 1235. Computing device 1100 may process the received signals using any suitable technique including determining the unique characteristics of the signals. Such characteristics may include, for example, the time duration between peaks of an EKG signal, the peak value or ratio between peaks of the EKG signal, or any other suitable characteristics as described herein. In a further step, computing device 1100 may be able to determine whether the previously detected user US is an approved user. For example, computing device 1100 may compare a library of signals associated with known approved users with the determined characteristics of the detected heart signals. If computing device 1100 determines that user US is not approved (e.g., the characteristics of the detected heart signals do not match the characteristics of the heart signals stored in memory), computing device 1100 may, in a further step, prevent access to the operations of restricted electronic devices. For example, computing device 1100 may prevent the user from accessing personal or private information associated with other users. As another example, computing device 1100 may prevent user US from accessing applications or operations associated with a particular user (e.g., applications purchased by a particular user). As yet another example, computing device 1100 may prevent user US from accessing the operations of any electronic device (e.g., operations other than emergency reporting).

[0163] Alternatively, if the computing device determines that the user US is approved, the process can proceed to a fourth step, where the computing device 1100 determines restricted operations associated with the user US. For example, the computing device 1100 can determine specific private data associated with the approved user (e.g., email accounts, contact lists, and banking information). As another example, the computing device 1100 can determine specific operations or applications associated with the approved user US (e.g., applications purchased by the user US using an app store, or system control operations associated with an administrator account). In a fifth step, the computing device 1100 can provide access to the determined restricted operations of the user US. For example, the computing device 1100 can load the determined data. As another example, the computing device 1100 can provide a link to launch the determined personal or private application.

[0164] While a second application 1180 is in front of the display 1195 and being actively operated by the user US, the first application 1170 can also be executed in the background of the operating system 1160 and perform one or more of receiving, storing, and analyzing physiological data. For example, the second application 1180 can include an email application, a web browser, a music player, or a game that the user US operates while the first application 1170 and the external sensor device 1200 are measuring the user's physiological parameters in the background.

[0165] The external sensor device 1200 can have many form factors, depending on, for example, the form factor of the computing device 1100 and the convenience of the user US.

[0166] Figures 2A through 2K illustrate a biometric or physiological parameter measurement and observation system 2000 that includes a smartphone 2100 and a smartphone protective case 2200. FIG. 2A shows a perspective view of the system 2200 with the smartphone 2100 and the smartphone protective case 2200 separated. The protective case 2200 has a recess 2200C for receiving the smartphone 2100. FIGS. 2B and 2C show rear views of the system 2000. FIG. 2D shows a perspective view of the system 2000 with the smartphone 2100 and the smartphone protective case 2200 coupled or removably attached to each other. The smartphone 2100 can include, for example, an Apple iPhone (registered trademark), a Google Android smartphone, a Google Nexus, a Samsung Galaxy phone, an HTC smartphone, a Nokia Windows smartphone, a Blackberry smartphone, and the like.

[0167] The smartphone 2100 may include a front face 2110, an edge 2120, a back face 2130, and a display 2140 on the front face 2110. The smartphone protective case 2200 may include a plurality of electrodes for detecting physiological parameters such as an electrocardiogram (ECG). The plurality of electrodes may include a first electrode 2210 and a second electrode 2220. The smartphone 2100 and the protective case 2200 are coupled together, and at least some of the plurality of electrodes are disposed to cover the edge 2120 of the smartphone 2100. In this way, for example, for user convenience, the thin and narrow profile of the smartphone 2100 can be maintained. As shown in FIG. 2B, the first electrode 2210 and the second electrode 2220 may be disposed opposite each other at the upper and lower edges (i.e., short sides) of the protective case 2200, respectively. As shown in FIG. 2C, the first electrode 2210 and the second electrode 2200 may be disposed opposite each other at the left and right edges (i.e., long sides) of the protective case 2200, respectively. FIGS. 2B and 2C show the back side 2200B of the protective case 2200. Each electrode is generally electrically insulated from each other to prevent short circuits or interference. Each electrode also generally protrudes slightly from the body of the protective case 2200. For example, each electrode may be polished, roughened, or otherwise finished to match the outer surface of the protective case 2200.

[0168] The sensor electrodes described herein may be constructed from any suitable material. The electrodes may be constructed from a particular material selected, for example, for its particular conductive properties that enable more effective transmission of electrical signals reflecting the activity of the user's heart. The electrodes may be constructed from a silver-based compound, which can provide superior conductivity compared to other metal compounds (e.g., steel or aluminum). The size and location of the electrodes may also be selected to ensure sufficient contact occurs between the user (e.g., the user's hand or finger) and the electrodes. For example, each electrode may include a pad or an extended area disposed on the outer surface of the body of the external sensor device 1200.

[0169] When in use, the user holds the system 200 by hand, touches the first electrode 2210 with the user's right arm RA, and touches the second electrode 2220 with the user's left arm LA, so as to measure one or more physiological parameters such as heart rate or ECG as shown in FIGS. 2E and 2F. As shown in FIG. 2E, the first application 1170 may be active on the system 2000 and display the measured parameters in real time. As shown in FIG. 2F, the second application 1180, such as an email application, may be active on the system 2000 and may be operated by the user US while the first application 1170 receives physiological parameter data in the background. By touching a plurality of electrodes with the right arm RA and the left arm LA, Lead I ECG can be measured. The user US may also touch the first electrode 2210 with the right arm RA and the left leg LL to measure Lead II ECG. The user US may also touch the first electrode 2210 with the right arm RA and the left leg LL to measure Lead III ECG.

[0170] Other arrangements of the plurality of electrodes are also contemplated. As shown in FIG. 2G, the first electrode 2210 and the second electrode 2220 may be disposed at the corners of the protective case 2200. Further, the plurality of electrodes may include a third electrode 2230. As shown in FIG. 2H, the first electrode 2210 and the second electrode 2220 may be disposed on the upper and lower edges (i.e., short sides) of the protective case 2200, while the third electrode 2230 may be on the lateral edge or long side of the protective case 2220. As shown in FIG. 2I, the first electrode 2210 and the second electrode 2220 may be disposed at opposite corners of the protective case 2220, while the third electrode 2230 may be on the lateral edge or long side of the protective case 2200. As shown in FIG. 2J, the first electrode 2210 and the second electrode 2220 may be disposed on the left and right edges (i.e., long sides), while the third electrode 2230 may be on the lateral edge or long side of the protective case 2200. In some embodiments, the first electrode 2210 and the second electrode 2220 may be disposed on the edge of the protective case 2200, and the third electrode 2230 may be disposed on the back surface 2200B of the protective case 2200.

[0171] When in use, the user holds the system 2000 by hand, touches the first electrode 2210 with the user's right arm RA, touches the second electrode 2220 with the user's left arm, and touches the third electrode 2230 with the user's left leg LL, so as to measure one or more physiological parameters such as heart rate or ECG as shown in FIG. 2K. As shown in FIG. 2K, the second application 1180, for example, an email application, may be active on the system 2000, and the first application 1170 may be operated by the user US while receiving physiological parameter data in the background. By contacting a plurality of electrodes with the right arm RA, left arm LA, and left leg LL, lead I ECG, lead II ECG, and lead III ECG can be measured. Lead I ECG, lead II ECG, and lead III ECG can also be measured simultaneously. The wireless ECG device having three electrodes is further described in the co-owned US Provisional Patent Application No. 61 / 845,254 filed on July 11, 2013 under the title of "Three-Electrode Wireless ECG Apparatus", the content of which is incorporated herein by reference.

[0172] FIGS. 3A-3F show a biometric or physiological parameter measurement and observation system 3300 including a tablet computer 3100 and a tablet computer protection case 3200. The system 3000 may be similar to the system 2000 in many respects. The system 2000 is adapted to be used with the smartphone 2100, while the system 3000 is adapted to be used with the tablet computer 3100. The tablet computer 3100 may include an Apple iPad (registered trademark), a Google Nexus tablet computer, a Samsung Galaxy tablet computer, a Microsoft Surface tablet computer, etc.

[0173] FIG. 3A shows a perspective view of a system 3000 in which a recess 3200C for accommodating a tablet computer 3100 is provided in a protective case 3200. The tablet computer 3100 has a front surface 3110, an edge 3120, a back surface 3130, and a display 3140. FIG. 3B shows the tablet computer 3100 coupled to or removably attached to the protective case 3200.

[0174] FIG. 3B also shows that a tablet computer protective case 3200 may include a plurality of sensor electrodes including a first electrode 3210 and a second electrode 3220. As shown in FIGS. 3B and 3C, the first electrode 3210 and the second electrode 3220 may be disposed facing each other covering the edge 3120 of the tablet computer 3100. Other alternative arrangements are also contemplated. For example, FIG. 3D shows the first electrode 3210 and the second electrode 3220 disposed on the back surface 3130 of the protective case 3200. Also, the plurality of electrodes may further include a third electrode 3230 disposed on the back surface 3130 of the protective case 3200 as shown by FIG. 3E.

[0175] The system 3000 can be used in a manner similar to the system 2000 described above for measuring physiological signals. For example, a plurality of electrodes of the system 3000 can contact a user US to measure one or more of Lead I ECG, Lead II ECG, or Lead III ECG. As shown in FIG. 3F, while the first electrode 3210 contacts the user's right arm RA, the second electrode 3220 contacts the user's left arm LA, and a third electrode 3230 (not shown) contacts the user's left foot, the user US can normally operate the system 3000 and the tablet computer 3100. FIG. 3F shows that a first application 1170 for managing the detected physiological parameters is active on the tablet computer 3100. Alternatively, it is also contemplated that while the first application 1170 and the protective case 3200 detect and sense physiological parameters, a second application 1180 is active and operated by the user US.

[0176] While the computing device is in normal use, other computing device accessories are contemplated for simultaneously measuring various physiological parameters of user US.

[0177] Figures 4A - 4C show a biometric or physiological parameter measurement and observation system 4000 comprising a keyboard 4100 of a computing device 1100 and a keyboard accessory 4200 that may include a keyboard wrist rest. The keyboard 4100 may be removably coupled to the keyboard accessory 4100 (compare Figures 4A and 4B). The keyboard accessory 4200 includes physiological parameter sensors such as a plurality of electrodes such as a first electrode 4210 and a second electrode 4220. As shown in Figure 4C, while user US is normally operating the computing device 1100 through the keyboard 4100, the first electrode 4210 may be in contact with the user's right arm RA and the second electrode 4220 may be in contact with the user's left arm LA to detect Lead I ECG.

[0178] Figures 5A - 5C show a biometric or physiological parameter measurement and observation system 5000 comprising a laptop or palmtop computer 5100 and a sensor accessory 5200. The computer 5100 may be removably coupled to the sensor accessory 5100 (compare Figure 5A and 5B). The sensor accessory 5200 includes physiological parameter sensors such as a plurality of electrodes such as a first electrode 5210 and a second electrode 5220. As shown in Figure 5C, while user US is normally operating the computer 5100, the first electrode 5210 may be in contact with the user's right arm RA and the second electrode 5220 may be in contact with the user's left arm LA to detect Lead I ECG.

[0179] Additional sensor accessories for coupling with devices for daily use are also contemplated. For example, embodiments of the present disclosure may provide sensor accessories for handlebars, seats, chairs, glasses, clothing, etc. of exercise machines such as bicycles, bikes, treadmills or elliptical machines or weightlifting machines. As another example, the sensor system described herein may be in the form of a watch, a wristlet, a wristband, or an accessory for such a device. ECG sensing watches and wristlets are described in the co-owned U.S. Provisional Patent Application No. 61 / 872,555, entitled "Ultrasonic Transmission of Signals from an ECG Sensing Wristlet", filed on Aug. 30, 2013. The sensor accessory may detect and measure one or more physiological parameters and communicate the measurement results to a computing device associated with a device for daily use or another computing device.

[0180] Figure 6 shows a method 6000 for the measurement and observation of biometric or physiological parameters. At step 6050, a computing device such as the computing device 1100 described herein may be provided. At step 6100, an external device or a shell of a computing device, such as the external device 1200 described herein, may be provided. At step 6150, the external device or shell may be coupled to the computing device. For example, see the system 2000 (Figs. 2A - 2D), the system 3000 (Figs. 3A - 3B), the system 4000 (Figs. 4A - 4C), and the system 5000 (Figs. 5A - 5C) described herein. At step 6200, a physiological signal or parameter measurement and observation application may be downloaded to the computing device. The application may comprise the first application 1170 described above and may be downloaded from an application delivery platform via the Internet as described herein. At step 6250, the application may be executed on the computing device. At step 6300, an external device or shell coupled to the computing device may contact the user to measure physiological parameters. At step 6350, a physiological signal or parameter may be measured. At step 6400, the physiological signal or parameter may be stored, displayed, or otherwise processed. At step 6450, the physiological signal or parameter measurement and observation application may be placed in the background of the computing device. At step 6500, while the physiological signal or parameter measurement and observation application is running in the background, a second application may be executed on the computing device.

[0181] The above steps illustrate a method 6000 for biometric or physiological parameter measurement and observation, but those skilled in the art will recognize many variations based on the teachings described herein. The steps may be completed in a different order. The steps may be added or omitted. Some of the steps may comprise sub-steps. Many of the steps may be repeated frequently to a beneficial extent.

[0182] One or more of the steps of method 6000 may be performed with one or more of the circuits as described herein, such as a processing device or logic circuit of a computing device, or their accessories. The processing device or logic circuit may be programmed to provide one or more of the steps of method 6000, and the program may comprise program instructions stored in a computer-readable memory of the logic circuit or in the programmed steps.

[0183] Generally, an apparatus and method for generating an electrocardiogram (ECG) from a patient are described herein, including a handheld wireless remote communication device case having three electrodes on an outer surface of the case, and methods of using the same. These apparatus and methods may enable a user to pick up up to six leads (e.g., lead I, lead II, lead III, aVR, aVL, and aVF) with a single handheld device, and these leads may be more easily held by the patient against the patient's legs while simultaneously observing the device's display. Specifically, the device may be used in conjunction with a mobile remote communication device (e.g., a smartphone). In another embodiment, the device may operate as a stand-alone device with appropriate circuitry for functioning independently or communicating with a separate remote communication device.

[0184] In general, the devices (including devices and systems) described herein may include three electrodes and are configured for use with a wireless remote communication device. The wireless remote communication device can be any suitable remote communication device, including smartphones (e.g., iPhone (registered trademark), Android (trademark), etc.), tablets (e.g., iPad (registered trademark), etc.), laptops, PDAs, and the like. The device can be configured as a case and / or attachment for a mobile remote communication device. The device can communicate information wirelessly to the mobile remote communication device. In some variations, the systems described herein transmit information to a mobile remote communication device that is configured to receive and analyze information from the device (e.g., by operating a program, application (“app”), etc.).

[0185] Thus, in general, the devices described herein may include a housing configured as a case or otherwise. The housing generally includes an outer surface on which three (or possibly more) electrodes are arranged. In variations where the housing is configured as a case for holding a mobile remote communication device, the case can have an outer back, at least two outer sides perpendicular to the back, and a front region through which the screen of the remote communication device held within the case can be viewed.

[0186] For example, FIGS. 9A through 9D show one variation of a housing configured as a case for a smartphone. In this example, case 300 is shown with a mobile remote communication device (smartphone) 301 housed within the case. Case 300 includes a back (shown in FIG. 9C) and sides (shown in FIGS. 9B and 9D). On the front of case 300 in this example, there is an opening 301 through which the front (including the screen) of the smartphone can be viewed and / or touched. The case can also include openings on the side (e.g., 9B) for the operating means of the phone.

[0187] Generally, the housing also includes at least (and in some variations exactly) three electrodes, one of each for contact with the subject's right hand, left hand, and leg. For example, the first electrode can be configured to be held against the patient's leg. The second and third electrodes can also be configured and arranged on the housing such that the patient can touch the second electrode with the right hand and the third electrode with the left hand while holding the first electrode against their leg. The placement, shape, and / or size of the electrodes can be configured such that when measuring an ECG, the patient's hand does not contact more than one electrode and the patient's leg also does not contact more than one electrode of the housing. For example, the first electrode may be disposed on the side or lateral edge (the back lateral edge) of the housing or both, but the second and third electrodes are disposed on the back, and all the electrodes are spaced far enough apart from each other to avoid the leg or hand contacting more than one electrode. Thus, the left hand can contact a single electrode, the right hand can contact a different electrode, and the leg can contact the first (leg) electrode, and all these electrodes are on the same housing.

[0188] In FIG. 9A, the electrodes are arranged such that the first electrode 309 is on one of the outer side surfaces of the case. By disposing the first electrode laterally on the case, it can be made possible for the first electrode to be easily held against the subject's leg while the patient holds the case, such that the patient's first hand (e.g., the left hand) contacts the second electrode and the other hand (e.g., the right hand) contacts the second electrode.

[0189] Generally, in any of the devices described herein, the electrodes can be on the outer surface of the housing. In some variations, the housing can be configured (or can include additional elements) to protect one or more electrodes from touching the surface when the device is placed on a surface such as a table. If the device is placed on a conductive surface (e.g., a metal table), the housing or additional features can prevent the outer surface of the electrodes from touching the surface. For example, the electrodes on the outer surface of the housing can be recessed with respect to at least a portion of the outer back such that when the case is placed on the table surface with the outer back facing the table surface, the outer contact surfaces of the first, second, and / or third electrodes do not contact the table surface.

[0190] As previously mentioned, placing the first electrode on the side can enable the use of the device to make measurements from the legs while viewing the surface (e.g., the screen) of a remote communication device within the case.

[0191] In FIGS. 9A - 9D, the case includes only three electrodes 309, 311, and 313, and the first (leg) electrode is disposed on the outer side surface of the housing. The horizontal (first) electrode is configured to extend along most of the horizontal length of the housing. The second electrode 311 and the third electrode 313 are disposed closer to the center of the outer back of the housing. As is apparent in the side views of FIGS. 9B and 9D, the housing protects the second and third electrodes since the height of the electrodes is lower than the rest of the outer surface of the case.

[0192] FIGS. 10A - 10D show another variation of a case having three electrodes. However, in this example, the first (leg) electrode 413 does not have an outer surface lower than the outer surface of the case, and instead, as shown in FIG. 10D, the third electrode protrudes from the outer surface. The case shown is similar in other respects to the variation shown in FIGS. 9A - 9D, but these figures are shown without a mobile remote communication device (e.g., a smartphone) within the case.

[0193] In some variations, as shown in FIGS. 11A - 11C, the leg electrode (electrode 1) 509 extends from the side surface to the back surface where the other electrodes 511, 513 are located.

[0194] Alternatively, in some variations, as shown in FIG. 12C, the leg electrode is disposed near the edge of the case (e.g., near the horizontal edge). Generally, the leg electrode may be adjacent to one of the side surfaces. The electrode may be immediately adjacent to the side surface or may be in contact with the edge. FIGS. 12A - 12C show a case configured such that the first electrode 613 is adjacent to the side surface of the case and the second electrode 609 and the third electrode 611 can be displaced from the first electrode and from the leg electrode (or other electrodes) to prevent inadvertent contact by the subject's hand.

[0195] FIGS. 7A - 7C show another variation of a case having a first electrode 709 that extends from the back surface through the horizontal edge to the side surface as shown. In this example, the second and third electrodes are recessed with respect to the outer surface on the back of the case, while the first electrode extends from the outer surface. This can make it easier to hold the case at an angle by contacting the leg.

[0196] In some variations, the housing may be configured to hold an electrode unit that fits into an opening on the outer back surface of the case, the electrode unit including the second and third (and optionally the first) electrodes and may also include circuitry for controlling / receiving ECG recordings. For example, FIGS. 14A - 14C show an apparatus configured as a case that holds an electrode unit 805 including a second electrode 811 and a third electrode 813 to be touched by the patient's right and left hands and a separate first electrode 809 on the side of the case. The electrode unit may protrude from the case and may include an outer (non - electrode) surface that extends longer from the outer surface of the case than the second and third electrodes to prevent the second and third electrodes from touching the table surface when the device is placed on the table.

[0197] Figs. 15A - 15C show another variation of the three - electrode housing, as shown in Fig. 15, where all three electrodes (the first electrode 909, the second electrode 911, and the third electrode 913) are arranged side - by - side on the back of the case.

[0198] Many of the variations described herein have all three electrodes integrated into the outer surface of the case, but in some variations, one or more of the electrodes may be configured to extend from the surface of the case. For example, in Figs. 16A and 16B, an example of a device having a first electrode 1009 that can be extended from the housing over a wire is shown. When not in use, the wire may be housed within the case and the electrode 1009 may be coupled to the case, and when in use, the electrode may be pulled out from the case and may contact the patient's leg so that the patient can hold the case and the smartphone and view them. In any of these variations, the smartphone may provide visual feedback to the patient before or during the recording. For example, indicating that good electrical contact is being made and / or showing the ECG trace taken by the system.

[0199] For example, Fig. 17 shows a method of operating a device 400 having electrodes for both hands (right hand, left hand) and electrodes for the legs. In this example, the subject SU is sitting on a chair CH and holds the device 400 configured as a smartphone case that holds a smartphone with both hands such that each hand touches only one of the electrodes on the back of the case. The case is held against the subject's legs such that the leg electrodes are pressed against the legs. Then, the case and the smartphone may be used to record leads I, II, and III, and as discussed above, at least three additional leads may be determined from them. Specifically, the augmented leads aVR, aVL, and aVF may be determined.

[0200] As described herein, a 12-lead ECG can be generated using three electrodes (e.g., by any of the devices described herein). For example, in one embodiment, as described herein, a device having three electrodes can be used to simultaneously determine Lead I (e.g., the voltage between the left and right arms) and Lead II (e.g., the voltage between the left leg and the right arm), and to simultaneously determine Lead I and Lead V2. In other embodiments, any other combination of leads is possible. Then, processing logic can align the times of the two sets of recordings so that the two sets of measurements can be compared over the same simulated period.

[0201] The processing logic can further transform two sets of leads to generate a complete 12-lead ECG. In one embodiment, the processing logic can perform such a transformation using a machine learning model (e.g., a neural network, deep learning technique, etc.). The machine learning model can be trained using 12-lead ECG data corresponding to a population of individuals. The data can be preprocessed to filter the data in a manner suitable for the application before being input into the machine learning model. For example, the data may be classified according to height, gender, weight, nationality, etc. before being used to train one or more machine learning models, thereby enabling the resulting one or more models to be fine-tuned for a particular type of individual. In further embodiments, the machine learning model can be further trained based on the user's unique ECG data to further fine-tune the model.

[0202] In one embodiment, using the machine learning techniques described herein, a complete 12-lead ECG can be generated using only three electrodes of a single device. As described herein, the three electrodes can be arranged on the device in any suitable manner, including two on the front and one on the back of the device.

[0203] Generally, devices and systems are also described herein for ultrasonic transmission by an ultrasonic transmission device of information (e.g., biological parameter information) from a wearable (e.g., a wristlet) detection device to a remote communication device that can then process and / or transmit the biological parameter information. Specifically, the biological parameter can include an ECG signal. The wearable device typically includes an ultrasonic transducer, which can be part of an ultrasonic modem module / subsystem for encoding and transmitting the information as an acoustic ultrasonic signal. In many of the variations described herein, these devices are configured as a wristlet worn by a subject.

[0204] As described in more detail below, in some variations, the ultrasonic signal (e.g., encoding the ECG) can be securely transmitted using an encryption key. Systems, methods, and devices are also described herein for easily pairing an ultrasonic transmission device to a remote communication device using an encryption key. For example, in some variations, the remote communication device can read (e.g., take an image of) the encryption key displayed on the ultrasonic transmission device. This technique can be readily implemented by taking an image of a mark (e.g., a barcode, a QR code (registered trademark), etc.) containing the encryption key with the remote communication device and determining the encryption key based on that image. Executable logic (e.g., decryption logic) executed on the remote communication device can be configured to interpret and apply this encryption key.

[0205] For example, a system capable of transmitting digital biological parameter information by ultrasound may include a sensor for detecting biological parameters (e.g., vital signs), a processing device for constructing a representation of the biological parameters as a "digital" ultrasound signal, an analog signal, or a hybrid digital / analog signal, and a transducer for converting the ultrasound signal so that it can be transmitted through open space to a remote communication-capable device. The processing device may be part of a controller (e.g., a microcontroller), may be controlled thereby, or may communicate therewith. The remote communication-capable device (remote communication device) may include a receiver (audio receiver) capable of receiving an audio signal in the ultrasound range and a processing device for converting the ultrasound signal back into an electrical signal for further processing or transmission.

[0206] It is often said that the human audible range is from 20 Hz to 20 kHz, but under ideal laboratory conditions, the maximum auditory range of children is actually up to about 12 Hz and rarely extends to about 20 kHz. Further, as shown in FIG. 18, the threshold frequency, i.e., the lowest intensity detectable, rises rapidly to the pain threshold between 10 kHz and 20 kHz. Thus, sounds above about 16 kHz must be of fairly high intensity to be heard. From shortly after birth, the threshold sound levels for these high frequencies increase. As shown in FIG. 19, the average 20-year-old has lost about 10 dB in the range of 8 kHz, and by age 90, the average person has lost over 100 dB at this frequency.

[0207] An exemplary product that uses very high frequency sound is a mosquito alarm, a controversial device that is used to intentionally emit an annoying 17.4 kHz alarm to keep young people from loitering. Since adults lose their hearing at this frequency, this sound is typically only audible to people under the age of 25. Similarly, students take advantage of adult hearing loss by using a "mosquito" ringtone on their cell phones in school that is in the 15 - 17 kHz range. The "mosquito" ringtone is audible to the students but not to the adult teachers. The term "ultrasonic" typically means beyond the range of human perception. However, as shown, the upper limit of the generally audible frequency range varies depending on the individual and age. Due to this difference in the upper limit, the term "ultrasonic" as defined in this specification and the appended claims may refer to sound frequencies of 16 kHz and above (e.g., higher than about 17 kHz, higher than 18 kHz, etc.).

[0208] However, interestingly, there is very little ambient sound or noise above about 10 kHz. Referring to FIG. 20, most everyday sounds occur at frequencies below about 4 kHz. Thus, the use of signals in the ultrasonic range not only results in quietness for people in the vicinity, but also a very desirable signal-to-noise ratio (SNR).

[0209] Audio engineers have reassuringly assumed that frequencies above about 20 kHz do not affect the perceived sound and can filter out all sounds above this range. Sounds below 20 kHz but in the ultrasonic range are mostly not a problem, and accordingly standard sampling procedures have been established. It is generally understood that sampling an analog signal, whether it is a wireless signal or an audible voice signal, requires a sampling frequency fs such that fs / 2 > f, where f is the frequency of the sine wave. For this reason, audio systems are designed to sample sound at a now-standard sample rate of 44.1 kHz, which is set somewhat higher than the calculated Nyquist-Shannon sampling rate of 40 kHz for the upper limit of 20 kHz sound. The actual demodulation of FM narrowband signals in the ultrasonic range, using existing demodulation procedures, computers, telephones, mobile phones, stereo audio systems, etc., reproduces the original signal very poorly. This is unfortunate because, as discussed above, carrier signals in the ultrasonic range have a very low signal-to-noise ratio due to the fact that there is little natural "noise" at these high frequencies.

[0210] Devices, methods, and systems for measuring physiological signals (e.g., biological parameters) and wirelessly transmitting digital information about those measurements silently use ultrasonic signals that have a much improved signal-to-noise ratio compared to conventional telephone transmission methods. Methods and algorithms are also provided for receiving and demodulating ultrasonic signals with great accuracy using existing computer and smartphone technology.

[0211] Figure 21A shows a schematic diagram of a system including a data input 0433 (providing any type of information, including for example digital and / or analog information) and a microcontroller 0405. In some variations, the microcontroller includes or is coupled with a processing device for encoding a digital representation of a biological parameter, and this encoded signal can be converted into an ultrasonic signal as will be described in more detail below. For example, the encoded signal can be transmitted ultrasonically by an ultrasonic transducer 0407. In some variations, the microprocessor and the transducer may be coupled together or formed as part of the same component 0405', or alternatively, the microprocessor may include a piezoelectric / speaker element. This ultrasonic signal 0420 can then be received by a remote communication device 0425 including an audio pickup (receiver) 0429. The remote communication device 0425 can execute client control logic 0427 that prepares the remote communication device to receive the ultrasonic signal and convert it so that it can be processed, for example convert it back into an electrical signal, and interpret what type of signal it is (e.g., heart rate, body temperature, etc.).

[0212] Figure 21B shows a schematic diagram of a system including a medical sensing device 0401 (such as a thermometer, a blood glucose monitor, etc.) having a sensor 0403 for detecting biological parameters (such as body temperature, heart rate, blood glucose, etc.) from a patient and a microcontroller 0405. The microcontroller may include or be coupled to a processing device for encoding a digital representation of the biological parameter, and this encoded signal may be converted into an ultrasonic signal as will be described in more detail below. For example, the encoded signal may be transmitted ultrasonically by an ultrasonic transducer 0407. This ultrasonic signal 0420 may then be received by a remote communication device 0425 including an audio pickup (receiver) 0429. The remote communication device 0425 may execute client control logic 0427 that prepares the remote communication device to receive the ultrasonic signal and convert it for processing, for example, to convert it back into an electrical signal and interpret what type of signal it is (such as heart rate, body temperature, etc.).

[0213] Accordingly, the medical sensing device 0401 in this example includes a sensor (or sensor assembly) configured to detect one or more physiological signals such as body temperature, heart rate, pressure (such as blood pressure). The sensor can generate an electrical signal representing the detected physiological signal, and these signals can be converted into one or more digital signals that are input to a microcontroller or other relevant components. This digital signal may typically be displayed on the device (not shown), or may alternatively be electrically encoded as part of a digital signal that can then be encoded ultrasonically (such as by a technique like frequency shift keying) and emitted from the device as an ultrasonic sound. The encoding of the signal can be performed by any suitable circuitry including a microcontroller (such as an MSP430) (such as the AFE4110 from Texas Instruments).

[0214] (Although not limited), a center frequency can be selected from any suitable ultrasonic frequency including 20 kHz. In some variations, since the medical sensing devices described herein are configured to only transmit, data is transmitted (but not received from) to a remote communication device. In some variations, the medical sensing device is configured to perform both transmission and reception of ultrasonic (acoustic) frequency information (see, for example, FIGS. 21C and 27). Further, in some variations, multiple channels (frequency channels) can be used.

[0215] In FIG. 21C, a schematic diagram of a medical sensing device (for example, a wristlet configured as an “ECG watch” to detect an ECG signal and transmit it to a remote communication device) is shown. In this example, the device (for example, the wristlet) includes a sensor 0403. In some variations, the sensor can include two or more electrodes for detecting an ECG signal. The ultrasonic transducer can be configured as both an ultrasonic transmitter and an ultrasonic receiver. In some variations, the same transducer element (for example, a piezoelectric element) can be used for both. The remote communication device 0425 can be configured to perform both receiving (via an audio pickup 0429) and transmitting (via an ultrasonic receiver 0433) ultrasonic waves such as those transmitted by the medical sensing device 0401.

[0216] In one embodiment, the ultrasonic signal has a center frequency in the range of about 17 kHz to about 32 kHz. In another embodiment, the frequency modulated ultrasonic signal has a center frequency in the range of about 18 kHz to about 24 kHz, or about 20 kHz to about 24 kHz.

[0217] Figure 22 shows one variation of a digital signal encoded using offset modulation. In this variation, the ultrasonic signal is modulated at two different frequencies, one indicating high ("1") and one indicating low ("0"). For example, the frequencies for 0 and 1 can be selected around approximately 20 kHz (e.g., 19.5 kHz and 20.5 kHz).

[0218] In some variations, as mentioned above, the sensor encodes the ECG signal, but generally, the sensor can include any suitable sensor operable to detect a physiological signal that the user desires to observe. Multiple sensors may be included. Non-limiting examples of such physiological signals include, but are not limited to, respiration, heartbeat, heart rate, pulse oximetry, photoplethysmogram (PPG), body temperature, etc. A respiration detector can be used. Heartbeat and heart rate can also be detected. For example, the oxygenation of a person's hemoglobin can be indirectly observed non-invasively using a pulse oximetry sensor rather than directly measuring from a blood sample. The sensor is placed on a thin part of the person's body such as a fingertip or earlobe, and light including both red and infrared wavelengths is passed from one side to the other. The change in the absorption rate of each of the two wavelengths is measured, and the difference is used to estimate the change in the oxygen saturation of the person's blood and the amount of blood in the skin. Then, a photoplethysmogram (PPG) can be obtained using a pulse oximeter sensor or an optical sensor using a single light source. The PPG can be used to measure blood flow and heart rate. Then, as described herein, the digital representation of this data can be used and transmitted. In some variations (described below with reference to FIGS. 26A and 26B), analog information can also be encoded and / or added to the digital information to form a hybrid of analog and digital information transmitted by the ultrasonic transmission device.

[0219] In some variations, the transducer assembly converts a biologically - parameter - electrically - encoded (e.g., digital, analog, etc.) signal into an ultrasonic signal that can be transmitted. In the embodiment shown in FIG. 21A, the transducer assembly 0405' includes an ultrasonic transducer 0407 for outputting an ultrasonic signal. Non - limiting examples of suitable ultrasonic transmitters (including transducers) include, but are not limited to, miniature speakers, piezoelectric buzzers, etc.

[0220] Within the remote communication device 0425, the ultrasonic signal can be received by a microphone 0429 of a device such as a smartphone, a personal digital assistant (PDA), a tablet personal computer, a pocket personal computer, a notebook computer, a desktop computer, a server computer, etc.

[0221] To conserve power, the volume of the signal may remain low, but a louder volume is also possible since the sound is inaudible. For example, at ultrasonic frequencies, the volume of the signal can be further increased without concern for the presence of a "listener" since it is inaudible. Additionally, the signal can be encoded to prevent other devices (not paired with the ultrasonic transmitting device) from receiving and understanding the signal.

[0222] As mentioned above, the remote communication device may include a processing device configured by client logic (e.g., software) for receiving and processing ultrasonic signals. For example, software on a smartphone can decode ultrasonic signals. The processing of the data may provide additional information related to the user, including the type of information (e.g., the nature of the biological parameter). For example, the signal may be encoded to include (after the start identifier) 8 pulses indicating ECG data, 10 pulses indicating a thermometer measurement (e.g., 4 digits with the last digit after the decimal point), 12 pulses indicating a blood pressure measurement (e.g., 3 digits for systolic blood pressure, 3 digits for diastolic blood pressure, and 3 digits for heart rate), 14 pulses indicating pulse oximeter data (e.g., 3 digits for oxygen saturation and 3 digits for heart rate), 16 pulses indicating glucometer data (e.g., 3 digits for blood glucose level), etc. There may be a "separator" between the digits and the EOM (end of message) indicator. In practice, the signal may be transmitted several times so that a comparison between the received data can be performed for verification.

[0223] In one variation, the signal may be encoded such as a number of AAs or 55s to enable synchronization (assuming 8-bit bytes and start and stop bits), a byte indicating the version number, the remainder of the 1-byte packet, a 1-byte packet identifier (0x01 for blood pressure, 0x02 for pulse oximetry, 0x03 for glucose, etc.), the data, and an 8-bit CRC.

[0224] In some variations, the signal may also include analog data having a spread (e.g., a signal over time, a signal over distance) for transmission together with digital information that formats or is extracted from the analog data (e.g., scaling the analog data). For example, a signal for ultrasonic transmission from an ultrasonic transmission device may include one or more digital portions and one or more analog portions. The digital portion may include information extracted from the analog signal, such as scaling (e.g., maximum and / or minimum values), time duration, average, etc. The analog signal, digital signal, and analog - and - digital (hybrid) signals may be encoded, including being encrypted, and / or may include error - correcting codes.

[0225] As mentioned, the signal may have a timestamp and / or a date - stamp. In some variations, a device or system may be configured to take multiple measurements and transmit them as a batch or burst to a remote communication device. For example, the measurements may be taken at times t1, t2, etc., stored in a device (e.g., a thermometer, a blood - glucose meter, etc.), and later (at tn) transmitted to a remote communication device (e.g., a smartphone, a tablet, etc.) via ultrasound. The data may be processed by the remote communication device and / or uploaded to an external server (e.g., the cloud).

[0226] The baud rate of the ultrasonic data transmitted may be selected to enable high - speed transmission. For example, when a baud rate of about 300 baud is used, transmission may take less than 1 second even for batch - processed signals. In some variations, the baud rate is around 400.

[0227] As mentioned, the raw signals and derived information from the sensors can be displayed on the smartphone, stored locally, and transmitted to a web server via an Internet connection. The software on the web server may provide a web browser interface for real-time display of the signals and information received from the smartphone or display of past signals and information, including further analysis and reporting.

[0228] As used herein, ultrasonic signaling generally refers to using ultrasonic signals to transmit information such as the magnitude of a biological parameter along with the origin of the biological parameter measurement result. As mentioned, these ultrasonic signals can be encoded to enable transmission and processing. The encoded signal can then be converted into the ultrasonic range by any suitable method. For example, one or more frequencies corresponding to various signal values, such as DTMF or DTMF frequency-shifted to ultrasonic frequencies, may be used. Another example of converting the signal is using amplitude shift keying. Another example is using frequency shift keying. Another example is using phase shift keying. In some embodiments, multi-carrier signaling, such as spread spectrum communication or multi-carrier carrier signaling, may be used. An example of multi-carrier carrier signaling is a predetermined set of frequencies (e.g., between 20 kHz and 22 kHz, or between 20 kHz and 24 kHz, or generally between a lower limit between 19 kHz and 20 kHz and an upper limit equal to or slightly lower than the Nyquist frequency of the intended receiver's sampling rate), spaced apart by an interval such as an interval between 40 Hz and 100 Hz, such as about 65 Hz. For each such frequency, a bit "1" is encoded to indicate the presence of a carrier signal, such as a sine wave at that frequency, and a bit "0" is encoded to indicate the absence of such a signal. A receiver of such a multi-carrier signal then performs a fast Fourier transform or a related technique known in the art to determine whether a carrier is available at each relevant frequency, thereby inferring a set of bits encoding a number. In some embodiments of multi-carrier carrier signaling, for example, when the signal clarity is insufficient, multiple samples can be taken over time and averaged, and the average signal can be processed as described above. In some embodiments of multi-carrier carrier signaling, for example, when the frequencies are close enough to cause interference, a Viterbi decoder can be used to decode the bit pattern. Generally, techniques known to those skilled in the art in the field of communication, particularly with regard to modulation and demodulation (e.g., modems), can be utilized.Examples of such techniques include various modem standards designated as V.x (where x is an integer) published by the Telecommunication Standardization Sector of the International Telecommunication Union, which are hereby incorporated by reference in their entirety for all purposes.

[0229] In some embodiments, rather than (or in addition to) on the remote communication device, a server may perform signal analysis to determine the encoded data. In some embodiments, the signals may be stored at the server and provided to personnel for improving transmission and / or reception techniques.

[0230] As mentioned above, signaling can be performed by a transmitter. The transmitter can include a hardware system incorporating a signal generator, such as a digital signal processor connected to a processing device, a microprocessor, a microcontroller, or a memory (e.g., DRAM or SRAM, which may be integrated with the processing device in some embodiments) containing program instructions executable by the processing device and / or data used by the program. The transmitter can also incorporate a persistent memory, such as a flash memory, coupled to and / or incorporated within the processing device. The signal generator can generate the ultrasonic signals to be transmitted as described above. In some embodiments, the waveform for transmission can be stored in the persistent memory. In some embodiments, the transmitter includes a power source and / or battery, or uses a power source used to power other components of the medical sensing device. As mentioned, the transmitter can include a transducer, such as a piezoelectric transducer that converts an electrical impulse into ultrasonic vibrations. The transmitter can include an amplifier coupled to the processing device (e.g., directly or indirectly via, for example, an audio digital-to-analog converter (DAC), which may be integrated with the processing device in some embodiments), and the processing device provides an electrical impulse to the transducer through its output. In some embodiments, the transmitter can include a receiver for receiving a real-time clock and / or a broadcast time signal. In some embodiments, the transmitter can include an encryptor, which may be, for example, program instructions executed on the processing device or a separate integrated circuit. In some embodiments, the transmitter can include an error correction code generator and / or an error detection code generator, which may be, for example, software instructions executed on the processing device or separate integrated circuits. The techniques described herein regarding the transmission and reception of acoustic signaling can be performed in the transmitters described herein in a manner that will be readily understood by those of ordinary skill in the art.

[0231] In some variations, the transmission from the medical sensing device to the remote communication device is unidirectional, typically resulting in a simpler design, lower cost, less power consumption, etc. These advantages can be particularly useful when compared to systems where the medical sensing device includes additional receivers (such as a microphone for receiving acoustic signals or an antenna). However, in some configurations, the medical sensing device can be adapted to receive a simple indicator signal from the remote communication device without adding a receiver such as an antenna or a microphone. For example, in some variations, an ultrasonic transducer (such as a piezoelectric speaker) can be used as a 20 kHz sensor so that an acknowledgement (ACK) of the reply can be implemented. For example, a remote communication device (such as a phone) can generate a short 20 kHz burst after receiving, decrypting, and verifying a cyclic redundancy check (CRC) to signal to the sensor that the CRC was received correctly and that no retransmission is required. In other variations, a signal from the remote communication device can indicate that the biometric device is ready to receive transmissions. Pairs or multiple pairs of time-separated signals / acknowledgements can also be used.

[0232] In one example, the device or system is configured such that the data transmitted ultrasonically includes forward error correction (FEC), enabling the receiver to correct N bit errors. This can be particularly useful when the system is configured such that the biometric device (medical sensing device) is transmission-only (e.g., unidirectional). FEC can help ensure that the data is received correctly.

[0233] In some embodiments, the data transmitted by ultrasonic signaling can be processed to include error correction codes such as BCH codes, constant weight codes, convolutional codes, group codes, Golay codes such as Binary Golay codes, Goppa codes, Hadamard codes, Hagelbarger codes, Hamming codes, Latin Square-based codes, Lexicographic codes, sparse graph codes such as low-density parity-check codes, LT or "Fountain" codes, Online codes, Raptor codes, Reed-Solomon codes, Reed-Muller codes, repeat-accumulate codes, iterative codes such as triple redundant codes, Tornado codes, Turbo codes, or other error correction codes known to those skilled in the art. In various embodiments, such codes may be applied in a single dimension or multiple dimensions, combined, or combined with error detection codes such as parity and cyclic redundancy checks. The error correction codes can be decoded and applied to correct transmission and / or reception errors at the receiver or at a server that receives the communication from the receiver according to their respective techniques.

[0234] Example 1: Digital Thermometer In one example, a digital thermometer can be configured to include a digital ultrasonic modem. In this example, a digital thermometer based on the Texas Instrument MSP430 digital thermometer is adapted to include firmware so that the measured body temperature (digital data) can be transmitted ultrasonically to a mobile remote communication device (e.g., iPhone (registered trademark)). This example is specific to the APE 4110 microprocessor (a variant of Texas Instruments' MSP 430 microprocessor), but other microprocessors may be used and adapted in a similar manner with firmware, software, and / or hardware to function.

[0235] Generally, a device may take data (e.g., a thermometer's body temperature measurement) and encode them for ultrasonic transmission. The encoded signal may include error checking (e.g., CRC encoding, Hamming codes, etc.) and may be encrypted. For example, the data may be data encrypted using, for example, the Advanced Encryption Standard (AES). Both U.S. Patent Nos. 5,481,255 and 5,452,356 describe data encryption methods and techniques that may be used with the data described herein.

[0236] For example, data received from a thermometer may be encoded and / or encrypted into one or more data packets for transmission. A microprocessor may encode the data and then transmit the packets by driving a piezoelectric speaker. As mentioned above, frequency shift keying (FSK) may be used, in which two distinct ultrasonic frequencies (e.g., 18817 Hz and 19672 Hz) are used to transmit Boolean 0 and 1, respectively. Control logic (data ultrasonic modem logic) may perform both constructing, encoding, and encrypting the data and controlling the driving of the prepared packets of the encoded / encrypted data for transmission by a speaker (e.g., a piezoelectric transducer). The control logic may also control the timing of the delivery so that there is an appropriate interval between each data bit. In addition, the control logic may also repeat the transmission and determine the time to start the transmission.

[0237] For example, in one variation, the thermometer normally measures body temperature, and when the body temperature stabilizes at a certain value, the thermometer emits an audible beep to inform the user that the value can be read. This thermometer (in its original unmodified configuration) includes a microcontroller (e.g., AFE4110) and a piezoelectric speaker, and the microcontroller drives the speaker to emit the beep. By modifying / configuring the microcontroller described herein to include control logic for a digital ultrasonic modem, the thermometer can be adapted to "wirelessly" transmit (via ultrasound) thermometer data to a device configured to receive and decode / decrypt signals, such as a smartphone that executes digital ultrasonic modem receiver logic.

[0238] In this example, the microprocessor may include the following (exemplary) code to enable the functions described above. FIGS. 23 and 24A - 24E show flowcharts illustrating methods for transmitting data. These examples are not limited to digital thermometers and may be used with any of the devices described herein, including ECG transmission.

[0239] The steps above illustrate the methods of FIGS. 23 and 24A - 24E for transmitting data, but those skilled in the art will recognize many variations based on the teachings described herein. The steps may be completed in a different order. Steps may be added or omitted. Some of the steps may include sub - steps. Many of the steps may be repeated frequently to a beneficial extent.

[0240] One or more of the steps of the method of FIGS. 23 and 24A-24E may be performed with one or more circuits as described herein, such as a processing device or logic circuit of a computing device, or an accessory thereof. The processing device or logic circuit may be programmed to provide one or more of the steps of the method, and the program may comprise program instructions stored in a computer-readable memory or programmed steps of the logic circuit.

[0241] In any of the systems, devices, or methods described herein, data (including digital data, analog data, and / or hybrid digital / analog data) may be compressed before being encrypted. Any suitable data compression technique may be used. For example, data compression may be performed using lossy and / or lossless techniques. Known types of lossy data compression and lossless data compression may be used. For example, Lempel-Ziv (LZ) compression and other statistical redundancy techniques may be used for lossless compression. Similarly, lossy data compression techniques may also be applied. A receiver that executes control logic may decompress the data.

[0242] As mentioned above, a receiver (digital ultrasonic modem receiver) may be used to receive the transmitted ultrasonic signal. The receiver may be a dedicated device that includes a microphone capable of receiving the ultrasonic signal and a processing device (e.g., a microprocessor) capable of analyzing the signal, or a device that has a microprocessor and a microphone adapted to receive the ultrasonic signal when executing control logic (e.g., digital ultrasonic modem receiver logic).

[0243] For example, FIG. 25 shows one variation of a flowchart showing a method for receiving, demodulating, and detecting a digital ultrasonic signal. In this example, the application (reception control logic) receives binary FSK-encoded data via a microphone input. For example, the input can be from the microphone of a smartphone. As discussed above, binary FSK encoding uses two frequencies: a "mark" frequency Fr to represent the binary value 1 and a "space" frequency F s to represent the binary value 0. In this implementation, a carrier wave is not used.

[0244] The application consists of two generally independent components: a demodulator that extracts the mark and space frequency components from the raw audio data, and a packet decoder that observes the demodulated signals for packet transmission and decodes them. These are shown in FIG. 25. The demodulator receives audio samples from the microphone hardware at a sample rate S such that S > 2*max(F m9 F8). The audio samples are processed by two frequency detectors that calculate (respectively) the intensities of the mark and space frequency components of the received signal. The Goertzel algorithm is used for frequency detection in this implementation. To achieve sufficient frequency resolution between the mark and space frequencies, the Goertzel algorithm is applied to a sliding window of G samples, where G = S / abs(F m -F).

[0245] The outputs of the Goertzel algorithm for the mark and space frequencies are passed through independent low-pass filters with a passband equal to the baud rate. Then, the filtered output of the space frequency signal is subtracted from the filtered output of the mark frequency signal. This produces a waveform that is approximately 0 when no transmission is taking place, rises to a positive value when the "mark" frequency is valid, and drops to a negative value when the "space" frequency is valid.

[0246] This demodulated waveform is then passed to a packet decoder. For each raw audio sample received from the microphone hardware, the demodulator produces a single demodulated sample of the demodulated waveform. The packet decoder receives the demodulated samples from the demodulator. The decoder maintains a buffer of the last N samples received, where N is equal to the length of the synchronization sequence. For each new sample, the decoder evaluates the past N samples in the buffer to determine if they contain the synchronization sequence. A two-step test is used: a computationally simple evaluation to remove most false positives due to random noise, followed by a more computationally expensive evaluation to remove the rest.

[0247] When a valid synchronization sequence is received, the decoder stores the characteristics of the received signal (e.g., maximum mark / space amplitude, etc.). These equalization parameters are used to calibrate the decoder thresholds used to read the rest of the packet. And now the decoder in this example reads each encoded byte. The decoder uses the stored equalization parameters to determine the minimum amplitude threshold for the start bit of each byte. When a valid start bit is received for a given byte, the subsequent bits are evaluated based on the sign of the demodulated waveform without a minimum threshold for decoding.

[0248] If a valid start bit is not received, the decoder aborts reading the packet and waits for silence or a fixed length of time to elapse before resuming listening for new packets. Each logical byte in the packet is actually transmitted as two encoded bytes: a first encoded byte containing the Hamming-encoded lower nibble of the logical byte, and a second encoded byte containing the Hamming-encoded upper nibble.

[0249] The first logical byte read is the packet version, which is verified against the supported version numbers. Next, the length of the packet is read, which specifies the number of subsequent data bytes. If the length of the packet exceeds the maximum length for the specified packet version, the packet is rejected. Subsequently, each logical data byte is read.

[0250] After the data bytes are read, two logical checksum bytes are read and the received checksum value is compared to the value calculated for the received data bytes. If these two checksum values match, the packet is considered valid and made available to the rest of the application. If they do not match, the packet is rejected. The two logical checksum bytes mark the end of the packet. After receiving a packet, the decoder resumes listening for new packets.

[0251] When data is received (and in some variations decoded), it is processed and further, and / or stored, and / or displayed, and / or transmitted using any of the communication capabilities of the remote communication device. For example, the data may be displayed on a smartphone and / or uploaded to a medical database for storage and / or later review.

[0252] The steps above illustrate the method of FIG. 25 for transmitting data, but one of ordinary skill in the art will recognize many variations based on the teachings described herein. The steps may be completed in a different order. Steps may be added or omitted. Some of the steps may comprise sub-steps. Many of the steps may be repeated frequently to a beneficial degree.

[0253] One or more of the steps of the method of FIG. 25 may be performed with one or more of the circuits as described herein, such as a processing device or logic circuit of a computing device, or an accessory thereof. The processing device or logic circuit may be programmed to provide one or more of the steps of the method, and the program may comprise computer-readable memory of the logic circuit or program instructions stored in the programmed steps.

[0254] The above example describes a system configured to transmit digital information, but the techniques, devices, and systems described herein may be configured to transmit analog signals as well as and / or analog and digital hybrid signals. In general, the techniques described include the use of a timer (e.g., in a microcontroller) that sends to a piezoelectric element to generate an ultrasonic signal. Alternatively, in some variations, the system uses a D / A converter to drive a speaker for non-digital output. Further, in some variations of the system, the output is a more conventional speaker (although in the ultrasonic range) rather than a piezoelectric element. Additional digital-to-analog (D / A) conversion may be performed during transmission.

[0255] For example, FIGS. 26A and 26B show one variation of a hybrid digital / analog format that may be used with an ultrasonic transmitter. In general, the signal may include a digital component that is modulated or configured for ultrasonic modem transmission. For example, the digital signal may be encoded as an FSK signal, and data (e.g., analog data such as biometric data such as ECG, blood oxygen / pulse oximetry, etc.) may be encoded as a frequency-modulated waveform added to the digital information.

[0256] For example, in some variations, the ultrasonic transmission device is configured as a pulse oximetry measurement / observation device. In this example, the information obtained from pulse oximetry may be scrutinized to extract information such as minimum value, maximum value, and time duration of the analog signal, and may be digitally encoded and stored in a buffer (using one or more encryption and / or error correction codes) and / or transmitted by ultrasound. The analog signal may be combined with a digital signal (or extracted signal) that is transmitted to a transmission element and received by a remote communication device. In an example of a device configured as a pulse oximetry device (e.g., a plethysmograph), the pulse oximetry device prepares a hybrid data / analog signal by determining, from an analog signal (e.g., a time-varying pulse oximetry signal), the peak, minimum value, time duration, time interval, etc. of the analog signal. Thus, the hybrid signal may include the extracted digital information or tagged digital information, as well as the waveform (or waveforms) obtained from the device.

[0257] In some variations, the signal can be ECG data. The ECG header information can include digital information about the analog waveform that is added to digital information such as time duration, heart rate, and information about the ECG waveform such as interval data (if pre-analyzed).

[0258] The signal can be encrypted and transmitted by a device or user-specific identification code. Generally, any of the devices described herein can encode data, and an encryption key can be provided so that a remote communication device on the receiving side (e.g., a phone, tablet, pad, etc.) can read and understand the data.

[0259] There are many potential advantages to transmitting hybrid analog / digital signals that can be read and understood by a remote communication device. For example, when the hybrid signal includes a series of values (e.g., minimum / maximum values) and waveforms (e.g., ECG, heart rate, etc.). This type of hybrid digital / analog system may enable more efficient communication than FSK value data alone.

[0260] For example, the variations of the ultrasonic transmission device may include a pedometer, an activity monitor, a heart rate monitor, etc. In some variations, the signal is formatted such that there are a finite number of points in the analog portion. The ultrasonic transmission device can then transmit a series of data points (including any data points including calibration points). In one example, a graph of heart rate may include 1000 points in 2 seconds (transmission time) representing a graph of biometric data over time. The signal may include digital values (e.g., encoded as FSK) and analog (e.g., graphic) data. Such a hybrid signal may include the best characteristics of both digital-only signals and analog-only signals.

[0261] In one example, as mentioned previously above, the ultrasonic transmission device is a thermometer that includes the ultrasonic modem element described above. The ultrasonic thermometer device is configured to include a temperature range of about 95°F to 106.7°F for the actual usage range. Thus, the body temperature can be transmitted such that it typically has a resolution of 0.1 (for example, all of what may require 8 bits since there are 120 values). In a device configured to encode byte metric data with a hybrid signal, the digital component of the signal may be added first, or may include information about the analog signal after a digital-only signal, but the analog signal may be added to or embedded in the rest of the signal, and the digital information may be extracted from the digital signal that should be included therewith. An example of a hybrid signal may include a thermometer device as mentioned above, which displays body temperature as a function of time, measured value, and / or recorded value, transmits the highest / lowest body temperature, measured time, etc., and ultimately, the signal may also include a body temperature waveform indicating changes over time. Other devices and / or signals (hybrid signals) may include a glucose monitor signal (for example, configuring the ultrasonic transmission device as a glucose meter, etc.), which may transmit a blood glucose signal (a digital signal including maximum value, minimum value, etc.) and one or more graphs showing the waveform of blood glucose values over time.

[0262] Preparing and transmitting a signal to include both analog and digital information may also enable the system to transmit more data in a compressed form as a waveform, which can be very efficient. For example, a prototype ultrasonic transmission device applies a specific sampling rate (for example, 300 or 500 samples / second, each value being a 16-bit binary value). More data can be efficiently transmitted in a compressed form as a waveform. By including information extracted from the digital part of the signal (such as the minimum and maximum values of the analog signal), calibration of the axis for the analog part of the signal can be performed, for example, for display.

[0263] As noted, FIG. 26A shows one variation of a hybrid digital / analog format that can be used as described herein. In this example, the signal includes an initial digital component 0901 that is encoded for ultrasonic transmission using a technique such as FSK (or any of the other techniques known in the art). The digital information can be appropriately decomposed into bits, bytes, words, etc. The size and arrangement of the digital information may be predetermined. Error correction codes (e.g., Hamming code, etc.) may be included. In FIG. 26A, the signal includes a start bit or byte 0905, a sequence of calibration data 0907 (e.g., maximum / minimum values) extracted from an analog signal, additional data 0909 for the analog signal (e.g., type, timing, date stamp / time stamp, etc.). Any other digital information may be included. Thereafter, the signal may include an analog component 0903. In FIG. 26A, the analog signal is somewhat free and may continue for a fixed or non-fixed length of time. In some variations, the entire signal can be repeated for reception by a remote communication device. FIG. 26B shows a similar variation of the hybrid signal format where the digital component 0901 is added to the analog component 0903 and an additional digital component 0911 (“end” signal) may be added last. In some variations, multiple analog components may be combined with multiple analog components. As described below, the entire signal may be encrypted before transmission.

[0264] In some variations, a hybrid digital / analog format can be used to encode stored data held by a device (ultrasonic transmission device) for a period of time. For example, stored data such as one hour of data, one day of data, or one week of data (e.g., biometric data such as pedometer data) can be prepared as an analog signal (graph over time) described / calibrated by a digital data component and transmitted to a remote communication device.

[0265] In any of the devices, systems, and methods described herein, the ultrasonic signals transmitted by the device can be encrypted. Any suitable encryption method can be used, including encryption methods that use keys, such as the Data Encryption Standard (DES), the Advanced Encryption Standard (AES), and the like.

[0266] Generally, for a particular device (e.g., an ultrasonic transmission device), the encryption key may be presented on the device (or on the associated package, housing, etc.) such that it is readily available to the user of the receiving remote communication device. The encryption key may be provided in a machine-readable format such as a barcode or other format (e.g., a QR code (registered trademark)), particularly a readable format that can be read using a receiving remote communication device of a modality different from ultrasonic transmission. As used herein, reference to presenting or displaying the encryption key on the ultrasonic transmission device is intended to include displaying an expression (and particularly a machine-readable expression) provided on the ultrasonic transmission device, its packaging, or an associated structure (e.g., a housing, etc.). In some variations, the encryption key is provided as a barcode or QR code (registered trademark) such that it can be photographed or scanned by the remote communication device and is printed on the outside of the ultrasonic transmission device. Machine-executable logic (e.g., client logic, software, firmware, etc.) on the remote communication device can then determine the encryption key and apply it to decrypt the ultrasonic signals received from the ultrasonic communication device.

[0267] In this way, the ultrasonic transmission device can be uniquely paired with a secret encryption key that can only be read by the remote communication device that owns and applies the encryption key. The encryption key is easily displayed and readily determined by the remote communication device. Thus, in some variations, each ultrasonic transmission device may have a unique ID printed on the device and provide a code that must match the remote communication device. By scanning the printed encryption key, the remote communication device can decrypt the data.

[0268] Figure 27 schematically shows one variation of a system that includes an ultrasonic transmission device (the "source device" 01031) with a visible cryptographic key 01051 on the body of the device that can be read and applied by the remote communication device 01025 to decode the transmitted ultrasonic transmission. Figure 27 also shows one variation of a device and system where the ultrasonic transmission device (the "source device" 01031) is communicating bidirectionally (or limitedly bidirectionally) with the remote communication device.

[0269] As mentioned above, it can be useful to have communication between a remote communication device (e.g., a smartphone or computer) and an ultrasonic transmission device, such as a health management / fitness sensing device, a home automation and security device (door and window sensors, remote lighting switches, etc.), a potted plant water level detector, etc. For example, it would be useful to implement a half-duplex protocol so that the remote communication device (e.g., a smartphone / computer) can provide an acknowledgement (ACK) of successful reception of data (using the correct CRC) to the sensing device (source device or ultrasonic transmission device), and stop the retransmission of that data. Another use of this half-duplex protocol is to configure the remote device by transmitting parameters or information such as calibration data, personal information, etc. from the remote communication device.

[0270] For a simple positive response, the piezoelectric element / speaker used by a device (ultrasonic transmitting device) to send data can be used as a frequency-tuned sensor. Generally, a piezoelectric element for voice transmission can also be configured as a receiver. Using the piezoelectric element as a receiving sensor requires a relatively "noisy" signal (even if it cannot be heard), so the signal must be at the resonant frequency of the piezoelectric element where its sensitivity is highest. The duration and coding of such "frequency bursts" can be configured to be easily recognized by the low-power electronics of a health management / fitness sensing device. For example, a positive response pulse can be filtered and detected as simply the presence of a certain ultrasonic frequency for a predetermined duration.

[0271] In some variations, by simply changing the carrier frequency into the ultrasonic range, well-established telephone modem techniques can be used to achieve symmetric bidirectional communication. For example, telephone modem modulation techniques based on FSK (Frequency Shift Keying), QAM (Quadrature Amplitude Modulation), and PSK (Phase Shift Keying). These telephone modem techniques assume that only two devices are attempting to communicate. A radio frequency protocol can be used to enhance the modem protocol to allow multiple devices to communicate simultaneously without errors.

[0272] Implementations of such bidirectional communication techniques may include in the device additional processing power sufficient to perform the signal processing necessary to demodulate and decode the received audio. This processing power may require additional battery power and physical space in the device. A partial list of existing modem communication standards that may be adapted for ultrasonic communication may include ITU V.21 (300 bps, FSK) and ITU V.22 (1200 bps, PSK (phase shift keying)). See, for example, web pages such as ftp: / / kermit.columbia.edu / kermit / cu / protocol.html, http: / / www.LSU.edu / OCS / its / unix / tutorial / Modem Tutorial / ModemTutorial.html, http: / / www.dtic.mil / cgi-bin / GetTRDoc?AD-ADA499556, http: / / alumni.media.mit.edu / ~wiz / ultracom.html, http: / / nesl.ee.ucla.edu / fw / torres / home / Dropbx / good_paper_mico_controller.pdf, http: / / edocs.nps.edu / npspubs / scholarly / theses / 2010 / Sep / 10Sep_Jenkinds.pdf.

[0273] With respect to FIG. 27, the source device may include an additional transducer / microphone for receiving ultrasonic signals from the remote communication device and for supporting the processing (e.g., microprocessor / microcontroller logic) to control it, interpret the communication (which may be encoded and / or encrypted), and perform any command functions. Similarly, the remote communication device may include a speaker (piezoelectric element) configured to emit ultrasonic signals.

[0274] From the foregoing description, it is clear that the inventive concepts disclosed and claimed herein are well adapted to perform the objectives and obtain the benefits as referred to herein and as inherent in the inventive concepts disclosed and claimed herein. The presented embodiments are described for purposes of the present disclosure, but it will be understood by those skilled in the art that numerous changes can be made which are readily apparent and which are achieved within the scope of the spirit of the inventive concepts disclosed and claimed herein.

[0275] Example 2: Heart rate monitor using an audio tone for transmission of heart rate Any of the devices, systems, and methods described herein can be configured as a wireless (ultrasonic) heart rate monitor adapted for use with a mobile remote communication (computing) device such as a smartphone. See also Example 3 below, which describes a wearable ECG monitor that can also provide heart rate information (e.g., by extracting the heart rate from a detected ECG signal). A wearable component for detecting heart rate (e.g., a wearable monitor) may be configured as a wristlet, anklet, armband, chest strap, belt (collectively "strap"), etc., and may wirelessly transmit information via any of the ultrasonic methods described above, including the use of receiving-side control logic (e.g., software, hardware, etc.) for receiving, storing, and / or analyzing the detected (biometric) information.

[0276] Most heart rate monitors consist of a chest strap that incorporates an ECG amplifier, an R-wave detector, and circuitry to output an electromagnetic pulse typically 50 ms wide at 5 kHz when an R-wave is detected. This electromagnetic pulse is detected by a watch or other receiver, which then measures the interval between pulses and calculates and displays the heart rate. This configuration requires a special receiver that may not be present in a cell phone or computer, so without additional equipment, they cannot receive heart rate information. Since this configuration typically uses short-range electromagnetic transmission, the range is also limited to about 1 meter.

[0277] In one variation of the devices and systems described herein, the heart rate monitor may include a strap (e.g., a chest strap, a wristlet, etc.) that incorporates an ECG amplifier, an R-wave detector, and circuitry to output an audio tone (signal) typically 5 ms wide (e.g., within the ultrasonic frequency range from about 17 kHz to 30 kHz) when an R-wave is detected. This audio tone may be detected by a device such as a smartphone or other mobile computing device that uses the built-in microphone of the smartphone device, which can then measure the interval between tones and calculate and display the heart rate. The mobile computing device (e.g., a phone) may include software, firmware, or hardware (but typically software including an application or "app" that can be downloaded from a remote server) to control the mobile device to receive and analyze the audio (e.g., ultrasonic) tone, calculate the heart rate, store the heart rate, upload it, and / or display it.

[0278] One advantage of this system is that since the microphone circuitry already exists in a smartphone or other mobile computing device, no additional equipment is required to receive heart rate information, and the range can be made longer, up to 5 m or more if desired depending on the magnitude of the audio tone.

[0279] When audio tones in the range of 16 kHz to 32 kHz are used (e.g., ultrasonic, 17 kHz to 30 kHz, 17 kHz to 22 kHz, etc.), they are inaudible to most people, do not interfere with music or conversation, and are less susceptible to audio interference.

[0280] In some variations, the devices, methods, and systems can be configured so that multiple heart rate monitors can be used in close proximity, or so that one receiving device can receive heart rate information from multiple users simultaneously. It may be desirable for the heart rate information from each heart rate monitor to be uniquely distinguishable so as not to interfere with each other.

[0281] For example, the audio tones from each heart monitor can be uniquely coded for each monitor by using a range of tone durations, multiple tones of the same frequency with a specific time separation, different audio frequencies, or combinations thereof.

[0282] A first embodiment is one in which each heart monitor uses different audio frequencies that are sufficiently separated to allow for Doppler shift when the heart rate monitor is moving rapidly relative to the receiver and to allow for frequency discrimination with a high signal-to-noise ratio.

[0283] Thus, each heart monitor does not have to be set to a specific tone frequency, and the frequency may be determined by a pseudo-random sequence when the R-wave heart signal is first detected after the heart monitor is initially attached. And the audio tone is fixed until the heart monitor is removed. Thus, it may not be necessary to code each monitor uniquely in this way.

[0284] When the heart rate monitor emits an audio tone in the range of 18 kHz to 22 kHz, a separation of 500 Hz can be used. This makes nine audio operating frequencies available for each monitor.

[0285] The pseudo-random allocation of the frequencies to be used can be achieved by providing a counter that increments with time since the heart monitor was first attached to the body, so that the counter value when the first R-wave is detected determines the audio frequency to be used. The audio frequency can be changed by removing the monitor from the body and reattaching it.

[0286] In the above example, two heart monitors are using the same frequency and are close together, so in the rare situation where there may be some interference, the frequency of one monitor can be changed by removing and reattaching that monitor. The receiving device can also detect such interference and advise the user to remove and reattach the monitor if necessary.

[0287] The receiving device can determine the audio tone frequency of a particular ultrasonic transmitting device (in this example, the heart monitor) by performing a spectral analysis of the received audio. Once the audio tone frequency is known, a narrow audio filter is used to separate the tones from each heart monitor. The audio tone can then be detected, and the heart rate is calculated by measuring the interval between the audio tones. Since the time duration of each audio tone is fixed, this information can be used to exclude interference from other audio sources within the frequency band.

[0288] The second embodiment is an embodiment in which a plurality of devices (for example, a heart rate monitor) use audio tones that have the same frequency but different durations. The duration of each tone can be measured by the receiving device. To calculate the heart rate for a particular heart rate monitor, only the tones of a particular duration are used. If two heart rate monitors are close together such that the receiving device picks up the audio tones from both monitors simultaneously, the receiving device can distinguish them based on the tone duration. Since the tone duration is short compared to the interval between tones (the interval between heartbeats), the likelihood that the audio tones will arrive simultaneously is low, but if they do arrive simultaneously, the receiving device can recognize this and adjust the calculation of the heart rate to compensate.

[0289] In some variations, the audio signal emitted when a heartbeat is detected may be digitally encoded (for example, including a burst of a plurality of pulses at a high frequency), and the encoding (burst pattern) may be unique as mentioned above, or may be pre-selected (which may be random), and may be reset by the user (for example, by removing and reattaching the device).

[0290] Any of the examples discussed above may be included as part of a method, device, or system (including software). Thus, a system for measuring heart rate may include a monitor (such as a heart rate sensor) that includes a transducer for creating an audio signal (for example, one or more pulses) whose timing is determined in accordance with the patient's heart rate. Thus, the monitor operates as an audio repeater. The audio signal may be in the ultrasonic range. The system may also include control logic for controlling a mobile device such as a smartphone or tablet to receive and analyze an audio signal whose timing is determined in accordance with the user's heart rate. In some cases, instead of or in addition to a smartphone that executes the control logic, a dedicated receiver may be used.

[0291] In certain examples, the system may include an application for use on a mobile device, such as a smartphone, that uses an internal audio pickup (microphone) to receive an audio signal emitted by a sensor and controls the smartphone to calculate a heart rate from this audio (e.g., ultrasonic) pulse signal.

[0292] Example 3: A wristlet for detecting motion and / or ECG signals Figures 28A and 28B show another variation of a wearable device that can detect health parameters and transmit the health parameters ultrasonically to an observation station (e.g., a smartphone) controlled by control logic to receive information from and / or cause reception by the wearable device ultrasonically.

[0293] Figure 28A shows an external view of one variation of the device configured as a wristlet. The device may include one or more sensors for detecting biological parameters, such as a motion / vibration sensor, and one or more electrodes. In Figure 28A, the outer surface of the device is schematically shown. A first conductive (e.g., metal) window 01151 is visible on the outer surface of the wristlet, and a second conductive (e.g., metal) window 01153 is visible on the inner surface of the wristlet. These electrodes may enable the user to press the electrodes and the wristlet downward to make electrical contact with the skin. The inner electrodes may be in contact always or periodically during normal use. The conductive windows may also be thermally conductive and may be connected to a body temperature sensing module.

[0294] Since the wristlet can be flexible, it can be wrapped around the wearer's wrist and fixed. Since the wristlet can be bendable, when it is bent around the wearer's wrist, it stays in that position. In some variations, the wristlet is open. In some variations, the wristlet may be closed (forming a closed loop around the subject's wrist). The outer surface of the wristlet may be sealed from the inner surface to prevent damage and to make the wristlet sweatproof and waterproof during wear.

[0295] As shown above for the conductive window area, the outer portion of the wristlet can be adapted to send energy from the module within the wristlet through the outer protective housing. For example, the conductive window area shown above. The area of the wristlet covering the ultrasonic transducer 01184 can also be adapted to allow the passage of ultrasonic signals. In some variations, the ends of the wristlet are adapted to allow the passage of ultrasonic signals by including relatively hard end caps that can easily convert ultrasonic energy. In some variations, the outer (e.g., polymeric) covering is made of a material known in the art to be relatively ultrasonic-transmissive. In some variations, the end region (or the opposite end region) can also be adapted to enable recharging of the device's battery.

[0296] Figure 28B shows an exemplary internal schematic diagram of a wristlet showing the internal module (structure). As mentioned, any suitable sensors may be included, including any of those mentioned above. In this example, the wristlet includes a motion sensor 01186, which may be a high-precision motion sensor for tracking body movement. Other sensors in this example include a first electrode 01191 and a second electrode 01192 that may be electrically connected to the conductive windows 01151, 01153 on the outer surface. In some variations, the outer surface is the electrode. In other variations, a conductive surface extends around the lengthwise perimeter of the inner surface of the wristlet (e.g., towards the lower electrode), such that it is likely to contact at least a portion of the bare skin of the wrist whenever the device is worn. Similarly, the conductive surface outside the upper electrode may extend entirely around the outer (outward-facing) surface of the wristlet. Additional sensors may be included or omitted. For example, in one variation, the wristlet includes only the motion sensor and no electrodes.

[0297] In some variations, the wristlet also includes a tactile feedback element, a vibration motor 01194. This vibration motor may generate an oscillation frequency to provide feedback from the device to the user. In some variations, the wristlet also may include a button or contact area that enables the user to manually trigger one or more functions of the wristlet and / or the observation station, such as the transmission of data by ultrasound. The button may be pressed or activated through an outer cover that protects the wristlet, and the outer cover may indicate where the button can be pressed, by a pattern, color, etc.

[0298] The wristlet may also include one or more sensors, as well as a processing device 01183 for receiving and / or encoding information from the ultrasonic transducer 01184. As discussed above, the transducer may receive encoded / encrypted information from the processing device for transmission via ultrasound. When multiple sensors are included, the information may be encoded to indicate what data is included.

[0299] One or more memory modules (not shown) for storing the recorded information may also be included. The memory may be integrated with the processing device. In some variations, a separate ultrasonic detector 01194 may also be used, or the ultrasonic transducer 01184 may be capable of both transmitting and receiving ultrasonic signals. Thus, bidirectional ultrasonic communication may be possible between the device and an observation station (e.g., a smartphone executing cybernetics).

[0300] The wristlet may also include a power management system that includes a battery 01182, which is typically rechargeable. The battery may be relatively low power (e.g., a low voltage such as 1.5V) and sufficient to power the electronic device and the ultrasonic transducer. The processing device may manage the power, including charging the battery. The system may indicate (e.g., by vibrating a warning vibration pattern) that the battery level is low and charging is required.

[0301] During operation, the wristlet may be worn and used to observe a subject (e.g., physical activity), and the detected values of the subject may be recorded and / or transmitted wirelessly. For example, motion sensor data may be detected and transmitted via ultrasound to a mobile computing device (e.g., smartphone 01130). As discussed above, the detected data may be encoded and encrypted (e.g., as both analog and digital information), which may prevent interference between other devices (e.g., enable specific modulation between devices) and also enable error correction.

[0302] For example, a wristlet device (e.g., an activity monitor) can be worn by a subject. When worn, the device can record the wearer's movement (activity). The device can also include additional sensors such as a pair of electrodes. These electrodes can be used to measure an ECG across a patient (e.g., between the patient's wrists) when the subject presses on the outer surface of electrode 1. In some variations, pressing can cause the device to record a potential during this period. The recorded electrical signal may contain information about the heartbeat and the ECG, which may be passed directly or may be passed after first being analyzed by a processing device (including passing any analyzed information).

[0303] The device may be configured to transmit data continuously (e.g., via ultrasonic broadcast) and / or repeatedly, or may be configured to handshake with a smartphone (or other receiving station). For example, the wristlet device may be configured to standby until an ultrasonic trigger ("ready") is received by an ultrasonic transducer / detector (01184 / 01194). The wristlet may then communicate with the receiving station to transmit the collected data by means of the encoded / encrypted ultrasonic waves as described above. The system may be configured to transmit periodically or to attempt transmission when sufficient data has been collected.

[0304] In general, any of the techniques, components, and / or subsystems described above may be used with or combined with any of the other examples. For example, any of the ECG wristlet devices described herein may include any of the features mentioned above.

[0305] Example 3: ECG Detection Wristwatch Another variation of the ECG measurement device, configured to detect an ECG signal and transmit an ultrasonic signal that encodes the ECG data, is shown in FIGS. 29 and 30. In this example, the watch has been modified to include two electrodes. The first electrode (not visible in FIGS. 29 and 30) is placed on the back of the watch (the "wristlet") and contacts the wrist of the person wearing the device. The second electrode 01203 is placed on the "face" of the watch 01201, as shown in FIG. 29. Thus, the watch can operate as a single-lead ECG sensor and record Lead I (left arm / right arm). In some variations, the watch may include an additional electrode 01207, for example, beside the watch or in the strap area, which can be held against the subject's leg (right or left foot) to produce additional / alternative leads (e.g., Lead II, Lead III, etc.).

[0306] The watch may also include one or more controls and / or indicators. For example, the watch can also be configured as a clock (indicating time, etc.). The watch may include buttons, dials, etc. for selecting functions (e.g., on / off of ECG measurement, start of transmission of ECG information, etc.).

[0307] FIG. 30 shows a variation of the ECG device 01203 shown in FIG. 29 that transmits to a mobile remote communication device 01205. In this example, the mobile remote communication device is a smartphone (iPhone (registered trademark)) that operates as a receiving station for the ECG watch and is configured to receive the ultrasonic transmission of ECG information. Thus, the smartphone executes application software such that the processing device of the smartphone "listens" for the ultrasonic signal with an audio receiver (microphone) that senses the ultrasonic waves. The receiving device (the smartphone) then processes the signal and can display it in real time as the ECG signal is recorded, as shown in FIG. 30. In this example, the smartphone continuously receives, displays, and records the signal.

[0308] As mentioned, the signal can be processed before being displayed and / or stored and / or transmitted. For example, the signal can be filtered to remove artifacts and / or to smooth it. The signal can also be analyzed to automatically detect cardiac events (e.g., arrhythmias). The processing can be performed by the watch before ultrasonic transmission, by a receiving device (e.g., a smartphone) after transmission to the receiving device, or divided between them.

[0309] In some variations, as discussed above, the watch may determine / confirm that the receiving device (e.g., a smartphone) is ready to receive information. In some variations, half-duplex or full-duplex can be used. The watch may continuously broadcast the ECG data or transmit only when it is indicated that the receiver is ready to receive. In such variations, the device may store the detected ECG data for later transmission.

[0310] In the examples shown in FIGS. 29 and 30, the system also determines the heart rate from the ECG information. Additional information can also be extracted from the signal. As mentioned above, the signal can be transmitted by a device (e.g., a wristlet) as a digital ultrasonic signal, an analog ultrasonic signal, or a hybrid digital / analog ultrasonic signal. Further, the signal may be encoded. In some variations, as discussed above, the device includes a key that can be scanned by a smartphone to provide decoding / pairing between the smartphone (receiver) and the device.

[0311] Many of the exemplary devices described herein are wearable devices (e.g., wristlets, chest bands, pendants, jewelry, etc.), but the principles, modules, subsystems, and elements described herein can be used for other devices, particularly biological sensor devices. For example, a case or holder for a mobile remote communication device (e.g., a smartphone) can incorporate any of these aspects, such as encoding of ultrasonic signals, encoding as a hybrid digital / analog ultrasonic signal. Thus, in addition to wearable medical sensors, any stand-alone medical sensor can include any of these features.

[0312] When a feature or element is referred to herein as being "in contact with" another feature or element, it may be in direct contact with the other feature or element, or intervening features and / or elements may be present. In contrast, when a feature or element is referred to as being "in direct contact with" another feature or element, there are no intervening features or elements. When a feature or element is referred to as being "connected to", "attached to", or "coupled to" another feature or element, it will be understood that it may be directly connected, attached, or coupled to the other feature or element, or intervening features or elements may be present. In contrast, when a feature or element is referred to as being "directly connected to", "directly attached to", or "directly coupled to" another feature or element, there are no intervening features or elements. Features and elements described with respect to one embodiment, or shown as such, may apply to other embodiments. It will also be understood by those skilled in the art that a reference to a structure or feature disposed "adjacent to" another feature may have portions that overlap with, or underlie, the adjacent feature.

[0313] The terms used in this specification are for the purpose of describing particular embodiments only and are not intended to limit the invention. For example, as used herein, the singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The terms "comprising" and / or "comprises" as used herein, when stating the presence of the stated features, steps, operations, elements, and / or components, are further understood not to preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items and may sometimes be abbreviated as " / ".

[0314] To describe the relationship of one element or feature to another element or feature shown in the figures, spatially relative terms such as "under", "below", "lower", "over", "upper", etc. may be used herein for simplicity of explanation. It will be understood that spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation shown in the figures. For example, if the device in the figure is turned over, an element described as being "under" or "beneath" another element or feature will be oriented "above" the other element or feature. Thus, the exemplary term "under" can encompass both an orientation of above and below. The device may be otherwise oriented (rotated 90 degrees or other orientations), and the spatially relative descriptors used herein are to be interpreted accordingly. Similarly, terms such as "upwardly", "downwardly", "vertical", "horizontal", etc. are used herein for purposes of explanation only, unless clearly indicated otherwise.

[0315] The terms "first" and "second" may be used in this specification to describe various features / elements, but unless the context indicates otherwise, these features / elements should not be limited by these terms. These terms may be used to distinguish one feature / element from another. Thus, without departing from the teachings of the present invention, the first feature / element discussed below may be referred to as the second feature / element, and similarly, the second feature / element discussed below may be referred to as the first feature / element.

[0316] As used in this specification and the claims, including when used in the examples, unless otherwise specifically specified, all numbers may be read as if the words "about" or "approximately" preceded them, even if those words are not explicitly present. The phrases "about" or "approximately" may be used when describing magnitudes and / or positions to indicate that the value and / or position being described is within a range of values and / or positions that are reasonably expected. For example, a numerical value may have a value of + / - 0.1% of the stated value (or range of values), + / - 1% of the stated value (or range of values), + / - 2% of the stated value (or range of values), + / - 5% of the stated value (or range of values), + / - 10% of the stated value (or range of values), etc. Any numerical range described herein is intended to include all sub-ranges subsumed therein.

[0317] Preferred embodiments of the present disclosure have been shown and described herein, but it will be apparent to those skilled in the art that such embodiments are given by way of example only. Without departing from the present invention, those skilled in the art will now envision numerous variations, modifications, and substitutions. It should be understood that various alternative forms of the embodiments of the present invention described herein may be utilized in practicing the present invention. The following claims define the scope of the present invention, and it is intended that methods and structures within the scope of these claims and their equivalents be covered by the claims.

[0318] FIG. 31 is a flowchart of a method 3101 for performing a 12-lead ECG with a three-electrode device, according to some embodiments of the present disclosure. Method 3101 may be performed by processing logic that comprises hardware (e.g., circuitry, dedicated logic, programmable logic, microcode, etc.), software (e.g., instructions executed on a processing device to perform hardware simulation), or a combination thereof. In one embodiment, processing logic corresponding to one or more components or methods of FIGS. 1-30 may perform one or more of the following operations. For example, in one embodiment, the processing logic of processing device 1110 performs the following operations with respect to the individual components of FIGS. 1-30. In another embodiment, any other suitable processing device may perform the operations described.

[0319] Referring to FIG. 31, in block 3103, the processing logic may determine a Lead I (value) from the first electrical signal of the first electrode and the second electrical signal of the second electrode. The Lead I may be calculated according to any of the methods described herein. For example, the Lead I may be calculated based on electrical signals from a first electrode that contacts the user's first upper limb and a second electrode that contacts the user's second upper limb. In block 3105, the processing logic may determine a Lead II from the second electrical signal and a third electrical signal from a third electrode. In one embodiment, the Lead II may be calculated according to any of the methods described herein. For example, the Lead II may be calculated based on electrical signals from a second electrode that contacts the user's second upper limb and a third electrode that contacts the user's first lower limb. In one embodiment, the Lead I and the Lead II are measured in sequence (e.g., the user first places the electrodes for Lead I, obtains the measurement result, then places the electrodes for Lead II, and obtains the corresponding measurement result). In such a case, the processing logic may further align the Lead I and the Lead II in time. In another embodiment, the Lead I and the Lead II are measured simultaneously (e.g., the user places the electrodes for Lead I and Lead II and obtains both measurement results contemporaneously, concurrently, or substantially simultaneously).

[0320] In block 3107, the processing logic may generate Lead III (e.g., using (Lead III = Lead II - Lead I)). In another embodiment, Lead III may be generated directly from the electrical signals of the electrodes that contact the user. In block 3109, the processing logic may determine Leads aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 based on Leads I, II, and III by the processing device using a machine learning model trained using the measured 12-lead ECG data. In one embodiment, only the data of Leads I, II, and III are provided to the machine learning model, and the machine learning model provides a 12-lead output using only the data of Leads I, II, and III. In another embodiment, additional data may be used by the model as described below with respect to FIG. 32.

[0321] In another embodiment, the processing logic may determine Leads aVR, aVL, and aVF from Leads I and II using non-machine learning-based techniques. In yet another embodiment, the processing logic may further determine the V leads from a fourth electrical signal. For example, the processing logic may determine V2 or V5 or any other V lead based on the fourth electrical signal. The processing logic may then determine the leads and the remaining V leads based on Leads I, II, III, and the V leads by the processing device using a machine learning model trained using the measured 12-lead ECG data.

[0322] In block 3111, the processing logic may provide the leads of Leads I, II, III, aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 for display on the client device. In another embodiment, a subset of the 12 leads may be provided (or none of them may be provided).

[0323] In one embodiment, the machine learning model is constructed based on a deep convolutional structure. The input layer treats the multi-lead ECG as a spatial image with one dimension for the time axis and another dimension for a plurality of channels. The ECG channels may have the normal order of lead I, II, III, AVR, AVL, V1-V6. Alternatively, the ECG channels may have a more physiologically meaningful order called the "Cabrera format", in which the anterior leads are in the order of lead aVL, I, -aVR, II, aVF, III, V1-V6. In another input format, only the limb leads of the Cabrera format and the actually measured precordial leads are used to form the input ECG image.

[0324] The 2D convolutional layer can be used to process the input ECG image instead of the 1D convolutional model as used by most other ECG training models. The training model may include 4×10 blocks of convolutional / residual layers, followed by a 2×4 fully connected layer. The output layer is a multi-classification layer where more than one class, such as "myocardial infarction" and "left atrial hypertrophy", or "right bundle branch block" and "inferior wall ischemia", may be identified.

[0325] In one embodiment, the model is trained using a large labeled training set with many epochs. Random connection exclusion and batch normalization can be used to prevent overfitting and enhance generality. The data is split into a training set, a validation set, and a test set. The validation set is used to prevent overfitting and training during the training process. The test set is used for final performance verification. The dataset is first formed using an existing 12-lead diagnostic ECG database. Then, a second dataset is formed using the actually sampled ECG from the target device described herein. Transfer learning can be used to adjust only a few layers of the deep learning model for the second dataset.

[0326] FIG. 32 is a flowchart of a method 3201 for machine learning training of a 12-lead ECG with a three-electrode device, according to some embodiments of the present disclosure. Method 3201 may be executed by processing logic comprising hardware (e.g., circuitry, dedicated logic, programmable logic, microcode, etc.), software (e.g., instructions executed on a processing device to perform hardware simulation), or a combination thereof. In one embodiment, the processing logic corresponding to one or more components or methods of FIGS. 1-30 may perform one or more of the following operations. For example, in one embodiment, the processing logic of processing device 1110 performs the following operations with respect to the individual components of FIGS. 1-30. In another embodiment, any other suitable processing device may perform the described operations.

[0327] Referring to FIG. 32, at block 3207, the processing logic may train a machine learning model using 12-lead ECG data corresponding to a population of individuals. In another embodiment, the model may be trained using data from a single individual (e.g., the user whose ECG is to be determined). In one example, the machine learning model may be trained to correlate measured data from leads I, II, and III with the measured 12-lead data. Once trained, the machine learning model may accurately predict each lead of the 12-lead ECG using only the data from leads I, II, and III.

[0328] Optionally, in block 3203, the processing logic may preprocess the 12-lead ECG data and classify the data based on at least one of height, gender, weight, or nationality before it is used to train the machine learning model. By preprocessing in this way, the model can be trained more efficiently and provide more accurate results specific to the user for whom the 12-lead ECG is to be determined. For example, the processing logic may classify the 12-lead ECG data based on the characteristics of the individual (3205). In one embodiment, if an individual is identified as male, the 12-lead ECG data may be preprocessed to include only data corresponding to male subjects. In another embodiment, if an individual is identified as having a particular nationality, the data may be preprocessed to include only that particular nationality. Training the model using such preprocessed data may enable faster training of the model and provide more accurate results than were previously possible without such preprocessing.

[0329] In one embodiment, for example, by performing one or more machine learning operations, the features of the 12-lead data may be selected, extracted, and labeled for predicting the 12-lead ECG in real time from three leads. Such operations may be selected from the operations of ranking features, classifying features, labeling features, predicting features, and aggregating features. Alternatively, or in combination, the extracted features may be labeled and stored for offline training of a machine learning algorithm or a set of machine learning operations. For example, the operations may be selected from any of the above operations. Any number of machine learning algorithms or methods may be trained to predict the 12-lead ECG from three leads. These may include the use of decision tree learning such as random forest, correlation rule learning, artificial neural network, inductive logic programming, support vector machine, clustering, Bayesian network, reinforcement learning, representation learning, similarity and distance learning, sparse dictionary learning, etc.

[0330] A machine learning-based algorithm or operation for predicting a 12-lead ECG from three leads may be provided as a service from a remote server that can interact or communicate with a client program, such as a mobile app, provided on a user's computing device. The interaction or communication may be through an application programming interface (API). The API may provide access to machine learning operations for, for example, ranking, clustering, classifying, and predicting a 12-lead ECG from three leads.

[0331] A machine learning-based algorithm or operation provided through a remote server and / or on a local application on a local computing device may act on, learn from, and make analytical predictions from, for example, 12-lead data and / or 3-lead data from a population of users.

[0332] The comparisons and analyses described herein can be used to lead to conclusions and insights about a patient's health state, which can include health problems a patient may experience at the time of measurement or in the future. The conclusions and decisions can be those that predict a future health state or diagnose a state a patient already has. The conclusions and decisions can also include insights about the effectiveness or risks associated with drugs or therapeutics that a patient may be taking, may have taken, or may consider taking in the future. Additionally, the comparisons and analyses can be used to determine actions and activities that can reduce or increase the risk of adverse events. Based on the comparisons and analyses described herein, ECG data can be classified according to the level of risk of the presence of an adverse event. For example, the ECG data can be classified as normal, low risk, medium risk, high risk, and / or abnormal. The designations of normal and abnormal may require the evaluation, diagnosis, and / or confirmation of a health care professional.

[0333] Diagnoses and decisions by physicians and other healthcare professionals of abnormalities, adverse events, or disease states can be transmitted to a server and database, tagged with and associated with corresponding ECG data. The diagnoses and decisions may be based on the analysis of the ECG data or may be determined using other tests or investigative procedures. The expert diagnoses and decisions may be extracted from a patient's electronic health record, entered into the system by the patient, or entered into the system by a medical professional. The conclusions and decisions of the system can be compared to the actual diagnoses and decisions by medical professionals to confirm and / or improve the validity of the machine learning algorithms used by the system. The time and duration of the occurrence of an abnormality, adverse event, or disease state can also be included in the database so that the ECG data corresponding to that occurrence, and / or the ECG data before and / or after the abnormality, adverse event, or disease state can be analyzed in association together. The length of time before or after an abnormality may be pre-determined and may be up to 1 day to 30 days, or longer than 1 month to 12 months. Analysis of the time before an abnormality, adverse event, or disease state can enable the system to identify patterns or correlations of various ECG characteristics preceding the occurrence of the abnormality, adverse event, or disease state, thereby allowing for the pre-detection or warning of the abnormality, adverse event, or disease state. Analysis of the time after an abnormality, adverse event, or disease state can provide information regarding the effectiveness of treatment and / or provide information to the patient or physician regarding the progression of the disease, such as whether the patient's condition is improving, worsening, or remaining the same. The diagnoses and decisions can also be used for indexing, for example, by including them in metadata associated with the corresponding ECG data.

[0334] As described herein, various parameters may be included in a database along with the ECG data. These may include the patient's age, gender, weight, blood pressure, medications, activities, habits, exercise, food consumption, beverage consumption, drugs, medical history, and other factors that may affect the patient's ECG signal. Additional parameters may or may not be used in comparing changes in the ECG signal over time and circumstances.

[0335] Conclusions, decisions, and / or insights regarding the patient's health generated by the system may be communicated to the patient directly or via the patient's caregiver (physician or other healthcare professional). For example, the patient may be sent an email or text message automatically generated by the system. The email or text message may be a notification instructing the patient to log on to a secure site to retrieve the full conclusion, decision, or insight, or the email or text message may include the conclusion, decision, or insight. Alternatively or additionally, the email or text message may be sent to the patient's caregiver. The notification may also be provided via an application on a smartphone, tablet, laptop, desktop, or other computing device.

[0336] As described herein, the system can identify behaviors, habits, activities, foods, beverages, therapeutic agents, drugs, etc. associated with abnormal ECG measurements of a patient. In addition to informing the patient of these associations, the system can provide instructions or advice to the patient to avoid these behaviors, habits, activities, foods, beverages, therapeutic agents, drugs, etc. associated with the patient's abnormal ECG measurements. Similarly, the system can identify behaviors, habits, activities, foods, beverages, therapeutic agents, drugs, etc. associated with normal or improving ECG measurements and can instruct or advise the patient to perform these behaviors, habits, and activities and / or consume these foods, beverages, therapeutic agents, and drugs. The patient can avoid future health problems by changing behaviors, habits as directed or advised by the system, or by adopting any activity guidelines, including but not limited to taking therapeutic agents, drugs, or following a diet or exercise program, which may be predetermined activity guidelines recommended by the system regardless of any analysis of the ECG data and / or may be derived from insights learned through this system and method as described herein. Additionally, the insights of the system may relate to general fitness and / or mental well-being.

[0337] ECG data, associated metadata, and other related data as described herein may be stored in a central database, a cloud database, or a combination of the two. The data may be indexed, searched, and / or classified according to any of the features, parameters, or criteria described herein. The system can analyze the ECG data of a single patient, and the system can also analyze the ECG data of a group of patients, where the group of patients can be selected according to any of the features, parameters, or criteria described herein. When analyzing data from a single patient, a comparison between one set of ECG data taken at a particular time and another set of ECG data taken at a different time is used to reveal differences due to changes in the patient's health state rather than changes in the type of ECG recording device used, changes in the placement of leads and electrodes, changes in the state of the skin (i.e., dry, sweating, conductive gel applied, or not applied), etc. It may be desirable to reduce and / or correct the variability within the individual's ECG data. As described above, a consistent lead and electrode placement can help reduce the variability of ECG measurements. The system can also retrieve the ECG data of patients taken under similar circumstances and analyze this subset of the ECG data.

Description of Symbols

[0338] 300 cases 301 Mobile remote communication device 309 Electrodes 311 Electrodes 313 Electrodes 400 Device 509 Electrodes 511 Electrodes 513 Electrodes 609 Electrodes 611 Electrodes 613 Electrodes 709 Electrodes 805 Electrode unit 809 Electrodes 811 Electrode 813 Electrode 909 Electrode 911 Electrode 913 Electrode 0401 Medical Sensing Device 0403 Sensor 0405 Microcontroller 0407 Ultrasonic Transducer 0420 Ultrasonic Signal 0425 Remote Communication Device 0427 Client Control Logic 0429 Audio Pickup 0431 Source Device 0433 Data Input 01005 Microcontroller 01007 Ultrasonic Transducer 01025 Remote Communication Device 01027 Client Control Logic 01029 Audio Pickup 01031 Source Device 01033 Input 01033 Ultrasonic Transducer 01051 Encryption Key 01053 Encryption Key Input 01130 Smartphone 01165 User Button 01182 Battery 01183 Processor 01184 Ultrasonic Transducer 01186 Sensor 01190 Vibration Motor 01192 Electrode 01194 Ultrasonic Detector 01201 Watch 01203 Electrode 01205 Mobile Remote Communication Device 01207 Electrode 1009 Electrode 1100 Computing Device 1110 Processor 1120 Memory 1130 Storage 1140 Network Interface 1150 Local Interface 1160 Operating System 1170 Application 1 1180 Application 2 1190 User Interface 1195 Display 1200 External Device 1210 Sensor 1215 Connection 1220 Processor 1230 Local Interface 1235 Connection 2100 Smartphone 2110 Front 2120 Edge 2130 Back 2140 Display 2200 Smartphone Protective Case 2210 Electrode 2220 Electrode 2230 Electrode 3100 Tablet Computer 3110 Front 3120 Edge 3130 Back 3140 Display 3200 Tablet Computer Protective Case 3210 Electrode 3220 Electrode 4100 Keyboard 4200 Keyboard Accessory 4210 Electrode 4220 Electrode 5100 Laptop Computer 5200 Sensor Accessory 5210 Electrode 5220 Electrode

Claims

1. an electrocardiogram device having a first electrode assembly, a second electrode assembly, and a third electrode assembly with a first electrode, a second electrode, and a third electrode adapted to measure a first electrical signal, a second electrical signal, and a third electrical signal, respectively, of an individual; determining a lead I from the first electrical signal and the second electrical signal; determining a lead II from the second electrical signal and the third electrical signal; Generate lead III using (lead III = lead II - lead I), determining leads aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 based on lead I, lead II, and lead III using a machine learning model that is trained using the measured 12-lead ECG data; Provides leads named Lead I, Lead II, Lead III, aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 for display on the client device and a processing device for:

2. The apparatus of claim 1 , wherein Lead II is determined sequentially with Lead I.

3. The apparatus of claim 2 , wherein the processing device is further for temporally aligning Lead I and Lead II.

4. The apparatus of claim 1 , wherein Lead II is determined simultaneously with Lead I.

5. 2. The apparatus of claim 1, wherein the processing device is further for training the machine learning model using the 12-lead ECG data corresponding to a population of individuals.

6. 6. The apparatus of claim 5, wherein the processing device is further for pre-processing the 12-lead ECG data to classify the data based on at least one of height, sex, weight, or nationality before the data is used to train the machine learning model.

7. The apparatus of claim 6 , wherein the processing device is further for characterizing the 12-lead ECG data based on characteristics of the individual.

8. 2. The apparatus of claim 1, wherein the processing device is further for training the machine learning model using only the 12-lead ECG data corresponding to the individual.

9. 1. A method for generating a 12-lead electrocardiogram, comprising: determining a lead I from the first electrical signal of the first electrode and the second electrical signal of the second electrode; determining Lead II from the second electrical signal and a third electrical signal from a third electrode; generating a Lead III using (Lead III=Lead II-Lead I); determining leads aVR, aVL, and aVF from leads I and II; determining leads V1, V2, V3, V4, V5, and V6 by the processing device using a machine learning model trained using the measured 12-lead ECG data based on Lead I, Lead II, and Lead III; and providing leads Lead I, Lead II, Lead III, aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 for display on a client device.

10. The method of claim 9, wherein the lead II is determined sequentially with the lead I.

11. The method of claim 10, further comprising the step of temporally aligning Lead I and Lead II.

12. The method of claim 9, wherein Lead II is determined simultaneously with Lead I.

13. 10. The method of claim 9, further comprising training the machine learning model using the 12-lead ECG data corresponding to a population of individuals.

14. 14. The method of claim 13, further comprising pre-processing the 12-lead ECG data to classify the data based on at least one of height, sex, weight, or nationality before it is used to train the machine learning model.

15. 15. The method of claim 14, further comprising classifying the 12-lead ECG data based on characteristics of the individual.

16. 10. The method of claim 9, further comprising training the machine learning model using only the 12-lead ECG data corresponding to an individual.

17. A non-transitory computer-readable storage medium storing instructions that, when executed by a processing device, cause the processing device to: determining a lead I from the first electrical signal of the first electrode and the second electrical signal of the second electrode; determining Lead II from the second electrical signal and a third electrical signal from a third electrode; The V lead is determined from the fourth electrical signal; Determine leads aVR, aVL, and aVF from leads I and II; (Lead III = Lead II - Lead I) was used to generate Lead III, determining, by the processing device, a lead and a remaining V lead based on lead I, lead II, lead III, and V lead using a machine learning model trained using the measured 12-lead ECG data; A non-transitory computer-readable storage medium that provides leads Lead I, Lead II, Lead III, aVR, aVL, aVF, V1, V2, V3, V4, V5, and V6 for display on a client device.

18. 20. The non-transitory computer-readable storage medium of claim 17, wherein Lead II is determined simultaneously with Lead I.

19. 20. The non-transitory computer-readable storage medium of claim 17, wherein the processing device is further for training the machine learning model using the 12-lead ECG data corresponding to a population of individuals.

20. 20. The non-transitory computer-readable storage medium of claim 19, wherein the V lead is at least one of leads V2 or V5.

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