A Wireless Body Area Network (WBAN) connects independent nodes (e.g. sensors and actuators) that are located in the clothes, on the body or under the skin of a person. The network typically expands over the whole human body and the nodes are connected through a wireless communication channel. According to the implementation, these nodes are placed in a star or multihop topology.
WBAN is a network of sensor nodes attached to the human body
The term “Wireless Body Area Network” was coined in 2001 by Van Dam. It is basically a network of sensor nodes attached to the human body that are used to measure the biological signals (heart rate, blood pressure, brain signals, etc.) . This network is mostly used in medical applications.
There are two types of communication in body sensor networks:
In-body communication
On-body communication
In-body communication is the communication between sensor nodes implanted inside the human body. MICS (Medical Implant Communication System) communication can only be used for internal communication. Body communication occurs between wearable devices including sensor nodes. The ISM (Industrial Scientific and Medical) band and UWB (Ultra-wide band) communication can only be used for upper body communication.
A WBAN offers many promising new applications in the area of remote health monitoring, home/health care, medicine, multimedia, sports and many other, all of which make advantage of the unconstrained freedom of movement a WBAN offers. In the medical field, for example, a patient can be equipped with a wireless body area network consisting of sensors that constantly measure specific biological functions, such as temperature, blood pressure, heart rate, electrocardiogram (ECG), respiration, etc. The advantage is that the patient doesn't have to stay in bed, but can move freely across the room and even leave the hospital for a while. This improves the quality of life for the patient and reduces hospital costs. In addition, data collected over a longer period and in the natural environment of the patient, offers more useful information, allows for a more accurate and sometimes even faster diagnosis.
An important step in the development of a WBAN is the characterization of the physical layer of the network, including an estimation of the delay spread and the path loss between two nodes on the body. This requires a detailed characterization of the electromagnetic wave propagation and antenna behavior near the human body.
Requirements of the WBAN network
Less power consumption
Interactive abillity
Self-healing
Security
Low latency
WBAN network architecture
The network structure is divided into 4 parts
1. Part WBAN
It contains a number of cheap and low power sensor nodes that can be used to continuously monitor a person's heart rate, ECG, blood pressure, etc. Being wireless in nature, this does not limit human mobility for continuous assessment. Therefore, WBAN is used in healthcare systems for patient monitoring.
2. CCU (Central Control Unit)
All sensor nodes provide output to a central dispatch node contained in the CCU. The CCU receives the signal from the nodes and transmits it to the next part to monitor the human body.
3. WBAN communication
Receives information from the CCU and acts as a gateway to deliver the information to the destination. For example, a mobile node is a gateway to a remote station to send messages to a mobile network using GSM/3G/4G.
4. Control Center
It is responsible for storing user information that can be used in the future or for monitoring purposes. This section includes end-node devices such as mobile phones (for messaging), computer systems (for monitoring) and servers (for storing information in databases).
WBAN applications
Here are the different applications of the WBAN network:
1. Medical Application
Remote Healthcare Monitoring - Sensors are placed on the patient's body to monitor heart rate, blood pressure, and electrocardiogram.
Telemedicine - Providing healthcare services over long distances with the help of IT and communication.
2. Non-medical applications
Sports - The sensor can be used to measure navigation, timer, distance, heart rate and body temperature.
Troops - Can be used to communicate between soldiers and send information about attacking, retreating or running to the commander.
Life and entertainment - Wireless music player and video calling.
WBAN is legal, affordable and user-friendly. This is an emerging technology and is expected to have a major impact on society.
