**2.1 System architecture**

The proposed monitoring system architecture is shown as Fig. 1 where the ring-type sensor measures pulse/temperature and transmits the physiological data to the reader using wireless RF, the biosignal recorder collects EEG/ECG/body-acceleration data and sends data to the

MCU data controller, the Bluetooth adaptors connected to the reader and the MCU data controller pass the data to the smart phone, and the smart phone records/displays the physiological data and also transmits data to the remote medical station using GPRS, HSDPA (3.5G), WiFi, or WiMax. The GPS built in the smart phone can provide the position information of the monitored person so that the medical personnel can be dispatched to the right location more promptly in an emergency situation. The proposed system architecture is capable of integrating additional physiological sensors via the MCU data controller. Therefore, it can be used as an e-coach to keep the user having healthy life style. It also can be applied to the baby-caring by detecting baby's pulse and/or ECG to identify whether the baby is being suffocated by pillow or blanket.

### **2.2 Hardware**

22 Health Management – Different Approaches and Solutions

recorder with a smart phone. The ring-type pulse monitoring sensor can measure pulse and temperature, while the biosignal recorder can record electroencephalogram (EEG), electrocardiogram (ECG), and body 3-axis acceleration during daily lives. The smart phone provides mobile "exercise-333" health management mechanisms. The user can monitor his/her own pulse and temperature from the smart phone where the "exercise-333" health management mechanism can help him/her to develop a healthy life style: taking exercise 3 or more times a week, at least 30 minutes per time, raising heart rate to 130 per minute. With the popularity and mobility of smart phones, this system effectively provides the needs for mobile

The proposed monitoring system architecture is shown as Fig. 1 where the ring-type sensor measures pulse/temperature and transmits the physiological data to the reader using wireless RF, the biosignal recorder collects EEG/ECG/body-acceleration data and sends data to the

health management.

**2.1 System architecture** 

Fig. 1. MHMS Architecture

**2. System architecture, hardware, and software** 

The hardware used in MHMS includes RFID pulse/temperature sensor tag (Ring) and RFID reader, Bluetooth RS232 adaptor, biosignal recorder, and smart phone.

### **2.2.1 RFID pulse/temperature sensor**

Although there is a ring-type pulse monitoring sensor in the market, shown as Fig. 2, the measured data are displayed in the LCD and cannot be transmitted out of the ring. In this paper, a RFID wearable ring-type sensor designed by Sinopulsar Technology Inc., Taiwan was adopted, instead. Fig. 3 shows this RFID ring (tag). This ring sensor is non-invasive, portable, and mobile. It can measure pulse and temperature signals which are processed by a built-in microcontroller. It uses optical sensors to detect heart rate and has anti data collision mechanism. Physiological data are then transmitted by RF wireless transmission with FSK modulation using UHF ISM band (up to 50 meters) to a RFID reader shown as Fig. 4. Fig. 5 illustrates the integration of Bluetooth adaptor, RFID ring (tag), and RFID reader.

Fig. 2. A commercial ring-type pulse sensor

A Mobile-Phone-Based Health Management System 25

The biosignal recorder, developed in this system for assessment of sleep depth and physical activities during daily lives, can measure electroencephalogram (EEG), electrocardiogram (ECG) and body acceleration signals. The size of this developed device (45mm *×* 25mm *×*  65mm, 62.5g) is more appropriate for ambulatory recoding than that of the well-known devices such as LifeGuard (Mundt et al., 2005) (129mm *×* 100mm *×* 20mm, 166g), AMON (Anliker et al., 2004) (286g) and Smart Vest (Pandian et al., 2008) (460g). Fig. 7 shows photographs of the developed device. The device consists of an analog part, a digital part

The analog part has five electrodes. Two of them are placed on the forehead and ear lobe for EEG acquisition. Another two electrodes are patched on upper-right and lower-left breast for ECG acquisition. The last electrode is put on back neck for right-leg-driving. The acquired signals are amplified by instrumentation amplifiers (Analog Devices AD627) and operational amplifiers (Texas Instruments TLV2254). The amplification factors are 60dB for EEG and 46dB for ECG. These amplification circuits also have bandpass characteristics with the passband from 0.5Hz to 100Hz. Then the conditioned signals are sent to the digital part. The digital part consists of a mixed-signal microcontroller, an accelerometer and a memory card. The mixed-signal microcontroller (Texas Instruments MSP430F4270) converts the conditioned signals (EEG and ECG) to digital signals with 16-bit resolution at the sampling rate of 256Hz. This microcontroller also collects three-axis acceleration values from the accelerometer (Freescale MMA7456L). This accelerometer provides 10-bit digital values whose range and sampling frequency are *±* 8g and 8Hz, respectively. The microcontroller records these digital data into the memory card. The memory card can store digital data up to 2GBytes, large enough for 2-week recordings. The power supply provides regulated voltage to other parts. The power source is one-cell lithiumion polymer battery (3.7V, 900mAh) and connected to a voltage regulator (Texas Instruments TPS73130) through a diode-OR circuit. This diode-OR circuit enables us to hotswap batteries. The principal parts of the developed device is enclosed in an ABS plastic case (Takachi SW-65S) whose size is 45mm *×* 25mm *×* 65mm. The overall weight of the device is 62.5g. Since the current consumption is 29mA in the steady state, the device can record EEG, ECG and three-axis accelerogram for up to 31 hours with the fully-charged battery. Furthermore, the measurement duration can be prolonged up to 2-weeks when two or more batteries are

Fig. 6. Bluetooth adaptor, RFID ring (tag) & RFID reader

used, swapped and charged alternately once a day.

**2.2.3 Biosignal recorder** 

and a power supply, as in Fig. 8.

Fig. 4. RFID reader
