بررسی سیستم مانیتورینگ بیمار از دور برای اندازه گیری پارامترهای فیزیولوژیک چندگانه A survey of remote patient monitoring systems for the measurement of multiple physiological parameters

1 Introduction Nowadays, progress in science and technology gives importance to the development of high performance monitoring systems with low cost, smaller size, high efficiency, high accuracy, etc. Many researches are focused on the design and development of RPMS to improve quality of human life, especially in rural areas. RPMS not only measures the physiological parameters, but also transmits the data in real time to healthcare professionals wirelessly [1]. This system is extremely useful for getting accurate and reliable information about body parameters and providing rapid access to health information. The general architecture of RPMS can be represented as shown in Fig. 1. Wearable RPMS consists of many wearable sensors which measure the physiological parameters namely Blood Pressure, Blood Glucose, Blood Oxygen level (SpO2), Pulse rate, Body Temperatures continuously. All the physiological data are processed using microcontroller and sent to a doctor’s smartphone wirelessly for better health monitoring and analysis [2]. In order to avoid difficulties associated with monitoring parameters using conventional methods, non invasive methods are taken into account. There are many technologies available to measure vital parameters [3]. PhotoPlethysmoGraphy (PPG) based technology is one among these methods which is based on optical techniques. Blood volume changes in the arteries produce a proportional change in the light intensity transmitted or reflected through the very sensitive area of the body, such as finger tip, tongue, ear lobe etc. [4]. A PPG signal is obtained by passing an LED light through the body tissue [4]. Current research is going on the multi parameter monitoring system using Light Emitting Diode (LED) sensors such as Red, Infra Red (IR) Green, etc. and photo diodes. Sensors are fundamental elements of the RPMS which are designed to measure the body parameters accurately and reliably over a long duration. To achieve the benefit of wearable and continuous monitoring, the sensors should be small in size, low weight, low cost and transmission of data through wireless technologies. The battery life of the sensors should be long and low power technologies are preferred for long duration. Many attempts have been made with the development of small, wearable sensors over recent years [2, 3]. All the body parameters can be monitored using these wearable sensors [3].