|Title of Invention||
THREE LEAD ECG MONITOR USING MOBILE PHONE WITH EMBEDDED ELECTRODES
|Abstract||The invention is used for measurement,transmission,monitoring and diagnosis of Electrocardiogram through mobile phones.The ECG pickup ranges up to ten microvolt.Thr ECG singals also possess artifacts due to muscle movements.In the present device two electrodes are placed on the body of mobile phone and third electrode as a retractable arm.ECG signals are transmitted either in the MMS from or in the Audio from or as streaming video data form to another mobile phone or any other receiver from.ECG signal is transmitted through the mobile telephone network.ECG signal is received from three electrodes or Infra-red or Bluetooth or USB interface.ECG signals are display on calibrated screen.ECG signal is transmitted to the physician by automatic dialing number and sends the ECG when kept on the chest while experiencing cardiac discomfort.ECG signal is can be transmitted using Wireless LAN network to the desired destination.|
|Full Text||FORM 2
THE PATENT ACT 1970
(39 of 1970)
The Patents Rules, 2003
(See section 10 and rule 13)
1. TITLE OF THE INVENTION
Method and Device for Measurement and Transmission of Three Lead Electrocardiogram (ECG) through Mobile Phones.
2. APPLICANT (S)
1. Buch Kaushal Dipak
Nationality: An Indian
Address: B/7, Shefali Apartments,
Behind L. D. Engineering College Hostels, Ahmedabad-380 015.
1. PREMABLE TO THE DESCRIPTION
The following specification particularly describes the invention and the manner in which it is to be performed.
The present invention relates to the Method and Device for Measurement and Transmission of Three Lead Electrocardiogram (ECG) through Mobile Phones. The present invention is used for measurement, transmission, monitoring and diagnosis of Electrocardiogram through mobile phones.
Mobile phones have become an inevitable part of human life. The invention is to utilize this availability of the mobile phones for measurement and transmission of ECG signals. Major focus is on the modification of the existing mobile phones for pick up and transmission of ECG signal to the physician's mobile or hospital in emergency situations. The ECG pickup is carried out using three electrodes and various processing and transmission options. The equipment would be extremely beneficial and life saving due to instant diagnosis and medication. Also with this technology necessary cardiac monitoring can be done to explore causes of cardiac malfunctioning. The ability to provide probable diagnosis to the patient can help in instant medication. The processing of the signals can be done with the three electrode inputs and also various other external cardiac monitors can communicate with the hardware through Bluetooth, USB or infra-red medium, thus making it a very versatile device.
Electrocardiography and continuous monitoring of the cardiac activity are mandatory to derive the exact cause of cardiac malfunctioning. The diagnosis of heart is difficult without an ECG. At the time of
emergency, there is need for the physician to know the cardiac activity
to investigate the cause. Thus there is a need to transmit the ECG data
in times of emergency. Thus mobile phones, which have become an inevitable part of human life, are used to bridge this gap by transmitting the measured ECG through the mobile network to the physician mobile or to any other hospital for analysis and immediate treatment. Also implementation of electrodes and processing hardware within the mobile has helped in this single piece mobile phone with ECG enhancement. The diagnosis of the patient can only be done remotely with the availability of the cardiac data in term of ECG. The accessibility of the mobile network and handling emergency situations in remote areas is a feature which can utilized for transmission of such data in exigency.
In the existing method, the transmission is done using trans-telephonic ECG or using different methods of communication like FM etc. The shortcoming of this system is that when a real need arises a person may or may not be near to the location where such instruments are available. Moreover, these equipments are not handy and cannot be carried wherever one goes. Secondly, there is no possibility of displaying the ECG output on physician's mobile and hence there is still a chance of physician not being able to view the ECG signal, if not available in the hospital. Continuous monitoring systems also are not so advanced to communicate the malfunctioning of the heart directly to the physician on need basis. There is no provision of diagnosis and instant medication advice by the instrument itself in any
of the remote cardiac monitoring devices. In the present invention which occur due to reduced number of leads and also due to the reduced inter-electrode distance. This leads to rough ECG pattern which to an extent can be corrected while processing the signal applying several algorithms. Hence the processing overhead increases.
There can be slight change in the configuration of the ECG signal pattern which is due to improper contact or reduced electrode distance. But all these can be tolerated in times of exigency, when even this signal can be used to interpret the cardiac activity correctly.
To overcome such limitations the present invention relates to Method and apparatus for Measurement and Transmission of three lead Electrocardiogram (ECG) through Mobile Phones is invented.
The present invention is described with greater specific and clarity with reference to following drawings:
Fig. 1 represents the placement of Electrodes for ECG pickup on the rear side of the mobile phone.
Fig.2 represents the block diagram for processing of ECG signals by the mobile phone.
Fig.3 represent the block diagram for processing of ECG signals by the mobile phone using Freescale Digital Signal DSP 56803
Fig.4 represents the general block diagram of mobile hardware working as ECG measurement, Transmission, monitoring and diagnosis device.
Fig.5 represents the different modes of pickup of ECG signals and transmission of the same via mobile phone
Figure 1 shows placement of metal electrodes on the rear side of the
mobile phone which can be used for ECG pick-up when placed on the chest. These leads can be placed at a distance so as to suite the best configuration. In order to span more distance on the chest, so as to get a proper ECG configuration, one or more electrodes can be placed on the retractable arm as shown in the figure no. 1. Thus in any mobile, the shape of ECG pick up electrodes will depend on the best achievable configuration using the adjustment of the distance between fixed and retractable electrodes.
The ECG pickup ranges from one to ten microvolt. The ECG signals also possess artifacts (noise) due to muscle movements. Thus the primary requirement is to amplify this signal using high-gain low noise amplifier (preferably an operational amplifier) to boost its Signal to Noise Ratio.
Thereafter it is filtered for the artifact removal. This can be done using some analog filters (like Chebyshev, Butterworth, Equiripple etc.) of a desired order. The signal can be filtered using an adaptive signal processing approach . The signal has to be digitized then as it is required to be processed by a digital processor (chip) available on the mobile phone.
After these blocks there can be two different options. They are as shown in figure 2 and 3.
Option 1: Multimedia Messaging Service (MMS): The data is processed by processor SoC and then through the mobile phones' operating system (application layer) running on this chip, it can be sent to the pre-stored or dialed number through MMS (Multi-Media messaging service). Then the destined user can view the ECG on his screen and diagnose the cardiac malfunctioning.
Option 2: Audio Signals: The data is processed by the processor SoC and sent as an audio signal to the receiver's phone. This requires a lesser change in existing chips as it can be tied as a microphone input. The only disadvantage is the conversion of this signal back into the waveforms for display on the screen at the receiver side. This makes the receiver side more complicated. This is almost similar to trans-telephonic ECG transmission.
Option 3: DSP (Reference DSP Freescale 56803): If the processing needs to be complicated and includes compression or heavy decoding then Freescale's DSP 56803 can be used. The complexity of implementation in the existing chip is reduced. The software for programming the DSP has to take care of the smooth running of the DSP hardware. The block diagram of the DSP application is as shown in figure 3.
As shown in figure 4, the mobile processing can be made versatile to
include inputs from various external cardiac monitoring devices through different modes. Here inputs are through various mediums.
There are four fundamental methods suggested - USB port, which is normally available in mobile phones for data downloading and
uploading can be used as an interface to send the digitized ECG signals to the mobile phone for transmitting it to the desired destination.
The other three methods are based on wireless communication -Bluetooth which is a short distance wireless link can be used in between external monitoring device and mobile phone. For this both monitoring device and mobile phone need to be Bluetooth enabled.
Another method using Infra-red port (IRDA) can be used. This will be a high speed wireless data transfer option. Frequency modulation can also be considered for transmission of signals from external device to mobile phone.
Thus, the concept of telemedicine can be achieved using these methods of transmission of data using mobile phones.
Three lead ECG: The arrangement as shown earlier in Figure 1 possesses three electrodes on the body of the mobile phone on the rear side. The inter-electrode distance can be increased with the help of
one electrode placed on retractable arm, which is attached to the mobile body. Here the processing can be done using the pick-up taken from the three electrodes and is then given to the processing chip.
Bluetooth to Chip interface: Bluetooth technology which is a short distance wireless link can be used to provide input to this mobile phone's ECG processing hardware. Thus an external cardiac monitor having a Bluetooth interface can communicate with this mobile using Bluetooth and can be used for event or continuous monitoring. This block converts the Bluetooth received data into the interface format of the ECG chip.
USB to Chip interface: USB port used for data transfer between external cardiac device and mobile can be used. This can be used in continuous monitoring and event monitoring of cardiac signals. This requires signal conversion in to the ECG chip interface format which is done by this block.
Infra-red to Chip Interface: Infrared (IRDA) port can also be used for data transfer between an external monitoring device and mobile phone. The data format conversion from the externally received cardiac signal through the infra-red port can be done using this block.
ECG Processing Chip: The chip's basic functionality is to process the input ECG signal through multiple channels. It has inputs from all the formats as shown in figure 4. It compresses the signals, if required
and provides it to the memory for storage. It also interfaces with the mobile processor chip for data transfer and other control operations. The chip is configurable and can be operated in several modes. The chip provides filter, analog to digital converter and other processing circuits. This hardware can also be a part of the mobile processing chip. The diagnosis process can also be done by this chip, by comparing the received ECG with the standard ECG patterns available in the memory.
Mobile Processing Chip: This is the central controlling unit can is governed by on-chip operating system which may in turn be controlled by user interface. This controls all the functions of the mobile phone and also controls the ECG processing system. It has an interface with RF (Radio Frequency) module.
Memory: This is the basic storage device. This can be within the mobile phone hardware or an expandable memory which can be plugged in the mobile phone. Normally Flash based or SD cards can be used for storage. This is very useful for continuous monitoring and storage of ECG data. Also it can be used in diagnosis for storing standard ECG data for comparison with the input data.
RF Interface: The RF interface interacts with the radio channel of the mobile network. This interface also communicates with the mobile processing chip for transmission of data and processing of received data.
Maximum frequency of ECG signal is around 50 Hz. But this
may go upto 175 Hz in certain cases. Generally ECG signals are
sampled at around 500 Hz of ADC sampling frequency. It can be quantized using to either 10/12 bit depending on hardware and signal quality tradeoffs.
The artifact removal filter can be any analog filter of a definite order. The order and filter window depends on the signal to noise ratio (SNR) and system requirements. The filter can be adaptive or non-adaptive .
The pre-amplifier is a low noise differential amplifier with high gain. The bandwidth required is not very large due as it needs to amplify only upto 500 Hz. The range of amplification would be from several microvolts to few milli volts.
Successive Approximation or Flash type ADCs are suited and their choice depends on system design and speed. DC Baseline Compensation is optional - depends on the actual noise floor and stability of the filter.
Compression of ECG signals is optional. It depends on period of monitoring and bandwidth requirements or support of advanced functions. There are many algorithms available for ECG signal compression - the one suggested is the Piecewise Linear Approximation.
The final stage is to either packetize the signal or give it to application layer from System on Chip (SoC) for sending MMS. The application has to implement an algorithm to convert the data into waveform by plotting it to the scale and also sending MMS viewable exactly of the same size on the physician's (receiver's) screen (To the scale). Pre-compensation has to be made if it is required to combat the effect of noise present in the communication channel (Additive White Gaussian Noise), Raleigh Fading, Flicker, Frequency Selective Fading etc.
Similar thing holds true if the option for selection of audio signals is made for transmission of ECG signals. The chip can directly join the processing paths for microphone and the pre-processed ECG pickup signal. The decoding at receiver end would require conversion from acoustic signal to waveform on the display screen. This would require a very strong hardware and good application interface. The acoustical format of transmission would be advisable because it has already been proven in many trans-telephonic ECG machines .
Depending on the existing chip architectures available on the mobile phone, the level of complexity (features) required for hardware restructuring and implementation varies. The hardware implementation is quite feasible due to already available high performance DSP (Digital Signal Processing) / System on Chip (SoC) on mobile phones. Due to the advent of the multimedia application on
the mobile phones, the application software is strong enough to handle the ECG data for display.
Pickup of ECG can be taken using instruments like Holter Recorders or any other such device as shown in Fig. 5. These devices can be kept on the chest for a longer time or for specific event monitoring. Mobile phone can serve as communication equipment in case the data needs to be transferred from the device to distant monitoring terminal or to physician. This is extremely useful in emergency conditions or for better monitoring and storage.
Wireless LAN (IEEE Std. 802.11) for transmission of ECG data
As suggested earlier, in the methods of transmission of ECG picked-up through mobile phone or taken as an input to the mobile phone through external monitoring device, can be transmitted through the wireless LAN network to the desired destination. For this purpose, the mobile phone must have WLAN connectivity. This will be speedier mode of data transfer, if it is required to send the signals across the LAN or internet for diagnosis and treatment. Also it can be kept connected for longer duration and monitoring would be easier through this mode of communication. Hence, the wireless LAN (WLAN) can also be used as a medium for ECG Data transmission through mobile phones.
The present invention is novel and it directs to the new applications of
the mobile phones. The present invention proves to be "life-saving equipment". The implementation will not require drastic change in
hardware but will surely prove to be an efficient and an effective tool for people suffering from cardiac malfunctioning.
1. Three lead ECG monitor using mobile phone with embedded
electrodes consists of high-gain low noise amplifier, artifact removal filter such as chebyshev, butterworth or equiripple, digital signal processing chip, extra memory, RF interface, ECG
processing chip and three electrodes wherein two electrodes (1 and 2) are placed on the body of mobile phone and the third electrode as a retractable arm (3);
Wherein further the length and width of the retractable arm can be varied as per the requirement of measurement and the pick up in varying topologies of chest is done by the said retractable arm.
2. Three lead ECG monitor using mobile phone with embedded electrodes as claimed in claim 1 wherein ECG signals are transmitted either in the MMS form or in SMS form where only three lead axis information and heart rate are sent or in Audio form or as streaming video data form to another mobile phone or any other receiver form.
3. Three lead ECG monitor using mobile phone with embedded electrodes as claimed in claim 1 wherein data is converted into waveform by plotting it to the scale to fit to the size of receiver's screen with the indication of time verses voltage scale.
4. Three lead ECG monitor using mobile phone with embedded electrodes as claimed in claim 1 wherein ECG signal is transmitted to the physician either by packetizing the raw signal or giving the processed data from the System on Chip (SoC) to the application layer, specially developed for packetization of ECG data.
5. Three lead ECG monitor using mobile phone with embedded electrodes substantially as herein described with reference to the foregoing description and the accompanying drawings.
|Indian Patent Application Number||144/MUM/2007|
|PG Journal Number||36/2010|
|Date of Filing||24-Jan-2007|
|Name of Patentee||Buch Kaushal Dipak|
|Applicant Address||B/7,Shefali Apartments, Behind L.D.Engineering College Hostels, Ahmedabad-380 015.|
|PCT International Classification Number||G08B21/04, A61B5/0404|
|PCT International Application Number||N/A|
|PCT International Filing date|