Body Area Network (BAN)

Introduction

Presently, networking media has penetrated various global domains like healthcare and computer networks. One prominent development is the Body Area Network (BAN), aimed at detecting chronic diseases within the human body. Also known as Body Sensor Network (BSN), a BAN encompasses diverse networks monitoring and detecting the human body's system. This article explores BAN's role in global and cost-effective healthcare. In this article, we will look into the concepts of Body area network (BAN). It presents the applications, benefits, and challenges faced.

A brief history of BAN

BAN technology has a relatively short history as it emerged from the fusion of sensor networks and biomedical engineering. Professor Guang-Zhong Yang coined the term "body sensor network" (BSN) in 2006, defining the foundation of BAN technology. BSNs represent the baseline for power and bandwidth in BAN scenarios, yet the adaptability of BANs provides diverse applications beyond BSNs.

What is BAN?

The BAN, or Wireless Body Area Network (WBAN), involves wearable computing devices either implanted or surface-mounted on the body. With the surge in wearable tech like glasses and watches, the focus on wireless networking has escalated. BAN, a term coined for wireless technology paired with wearables, primarily aims to transmit wearable-generated data to WLANs or the Internet, sometimes allowing direct data exchange among wearables.

In the scientific realm, researchers continue integrating novel technologies for simplified monitoring, such as networks and sensors used in traffic and health monitoring. As a result, innovations like BANs or sensors enable the monitoring of internal activities like chronic diseases.

The BAN field holds promise for affordable, continuous health monitoring via the Internet. Wearable WBANs incorporating intelligent physiological sensors could detect medical conditions by implanting minute biosensors within the body. These sensors collect physiological variations to monitor the patient's health status.

Wirelessly transmitted data from BAN devices reach external processing units, allowing global access for doctors. In emergencies, immediate updates on the patient's health status are relayed to doctors worldwide.

Components essential for a BAN include active signal monitoring sensors, motion detectors to pinpoint the wearer's location, and communication tools for data transmission to caregivers or medical professionals. Typical BAN kits comprise sensors, batteries, transceivers, and processors. Physiological sensors like SpO2, ECG, BP, PDA, and EEG sensors are in developmental stages.

However, BAN faces challenges. Complex sensor manufacturing, safety concerns compared to other medical devices, and potential data transmission interruptions are among the obstacles.

Despite challenges, BAN finds applications in various fields, particularly in healthcare for disease monitoring, detecting chronic illnesses like heart attacks and asthma, in security, sports, and communication. The future foresees BAN technology permeating multiple sectors, revolutionizing monitoring, detection, and networking. Ultimately, BAN holds immense potential in reshaping technology. Understanding its components, challenges, and applications offers a glimpse into its transformative capabilities.

Standards: The most recent global standard governing Body Area Networks (BANs) is the IEEE 802.15.6 standard.

Components of BAN

A typical BAN or BSN requires sensors for vital sign monitoring, motion detection (usually through accelerometers) for identifying the monitored individual's location, and a means of communication to transmit vital signs and motion readings to medical practitioners or caregivers. A standard body area network kit comprises sensors, a Processor, a transceiver, and a battery. Several physiological sensors like ECG and SpO2 sensors have been developed, while others, such as a blood pressure sensor, EEG sensor, and a BSN interface Personal Digital Assistant (PDA) are still in development.

The Federal Communications Commission (FCC) has given the go-ahead for allocating a 40 MHz frequency bandwidth, ranging from 2360-2400 MHz, dedicated to low-power, wide-area radio communication within medical BANs. This decision aims to alleviate congestion within the conventional Wi-Fi spectrum by moving MBAN (Medical BAN) communication to this standardized band.

Challenges Associated with BAN

• Security: Securing WBAN transmissions for accuracy requires each patient's data to be isolated within their specific WBAN system. Despite its importance, WBAN security has received little attention, as limited processing power, memory, and processing capabilities present unique constraints to security solutions.
• Interoperability: Ensuring easy data transfer across diverse standards like Bluetooth and ZigBee is crucial for improved information exchange and device interaction within WBAN systems. Scalability and uninterrupted connectivity are additional objectives.
• WBAN Sensor Requirements: WBAN sensors need simplicity, lightweight build, energy efficiency, and user-friendliness. Correspondingly, storage systems should provide remote Internet access to patient data and external processing tools.
• Privacy Concerns: The more extensive acknowledgment of WBAN innovation beyond secure medical settings is extremely important in forestalling potential security breaks.
• Sensor Approval: Ensuring exact sensor readings and limiting deceptions are central in the medical services domain.
• Data Consistency: Effectively managing scattered patient data across multiple devices and ensuring seamless collection and analysis are vital.
• Interference Management: For large-scale WBAN deployment, reducing interference and enhancing compatibility with other network devices is critical.
• Data Handling: Efficiently managing and preserving the vast data generated by BANs is crucial for seamless operation and analysis.
• Human-Centric Challenges: Addressing aspects like cost-effectiveness, varying monitoring needs, unobtrusive implementation, consistent performance, and energy efficiency is crucial for practical BAN development. These factors significantly influence meeting consumer preferences and successful BAN implementation.
• BAN technology faces technical challenges beyond ethical concerns like privacy. Signal propagation in and around the human body and the usability of such technology remain significant hurdles.
• Signal & Path Performance: Signal and path loss within the human body, distinct from open space rules, present challenges. Researchers have modeled signal loss throughout the body and explored using the body as a transmission medium. Factors like frequency range, distance, body composition, and joint presence affect signal attenuation.
• Usability: The close proximity of BANs to users demands high usability. Advanced designs, like Zheng et al.'s wearable shirts, address previous usability issues by seamlessly integrating monitoring into everyday wear. Usability flaws, such as the EPI-MEDICS system's passive emergency detection, highlight the need for proactive emergency sensing.

WBAN Requirements

• Low power usage
• Interoperability
• Self-recovery capability
• Security
• Minimal delay.

WBAN Architecture

The structure consists of four segments:

• WBAN Part:

A network consisting of a number of cheap weak sensors for continual measurements of key signs like heartbeat, ECG, and blood pressure. Such wireless nodes permit free movement and continuous surveillance, which is a common feature of many medical applications such as patient monitoring.

• CCU (Central Control Unit):

Data is collected by all sensor nodes and transmitted to a central coordination node in the case of CCU. Nodes send signals that the system picks up and further transmits to the next section for checking the body's condition.

• WBAN Communication:

It is a doorway that receives information from the CCU and then transmits it to its destination. A case in point is a mobile node that functions as an entry point for messaging on GSM/3G/4G cellular networks for the remote station.

• Control Centre:

Used to hold user details to be used in future queries/modifications and tracking. For example, end-node devices include mobiles (for texting), computer systems (for monitoring), and servers (database storage).

WBAN Applications

1. Medical Applications:

• Remote healthcare monitoring: Sensing measures pulse, blood level, and an electrocardiogram of a patient's torso.
• Telemedicine: Use of tele-IT and telecommunications to deliver health care services at a distance.

2. Non-medical Applications:

• Sports: These include sensors for measuring navigation parameters, timers, distance, pulse rate, and body temperature.
• Military: Informs their base commander about tactical moves they have made and communicates with other soldiers.
• Lifestyle and entertainment: Playing music wirelessly and video call support.

Note: Being legal, affordable, and easy for everyday use, the WBAN technology will contribute greatly to society.

Benefits of WBAN

• Improved Health Care: WBAN helps in ongoing monitoring of patients to detect irregularities and notifies medical personnel about impending health threat situations.
• Greater Mobility: Thus, WBAN enhances patients' quality of life as they can mobilize without the need to carry medical devices.
• Improved Comfort: WBAN are of small sizes, lightweight, and less conspicuous, hence assuring high wear comfort for a longer time.
• Cost-effectiveness: There is a prospect that WBAN devices can reduce healthcare costs as their price is less than that of other medical equipment.
• Individualized Care: WBAN devices will enable customized healthcare services for different patients.

Constraints of WBAN

• Privacy and security concerns: Far-off correspondence might think twice about the security of delicate clinical information.
• Interference: WBAN gadgets could confront interruptions from other remote gadgets, prompting information misfortune or sign twisting.
• Restricted Inclusion: WBAN signs could have confined reach and battle to enter walls or impediments in specific conditions.
• Battery Reliance: WBAN devices rely on batteries, which must be recharged or replaced frequently depending on usage.
• Issues with Standardization: The absence of normalization among WBAN gadgets could cause similarity issues, restricting their interoperability.

Applications of BAN

Some prevalent BAN applications include:

• Body Sensor Networks (BSN)
• Sports and Fitness Monitoring
• Wireless Audio
• Integration with Mobile Devices

Let us delve deeper into a few applications of BAN.

• Personal Video Devices:

Each application comes with specific needs in terms of bandwidth, latency, power efficiency, and signal range. The IEEE 802.15 working group focuses on Wireless Personal Area Networks (WPAN), recognizing the necessity for standards applicable to devices in close proximity to the human body. Task Group #6 within IEEE 802.15 was formed to establish standards for BAN, aiming to offer a broad spectrum of potential devices through a drafted standard.

The BAN task group's standardization approach allows application and device developers to decide the trade-off between data rate and power. Figure 1 illustrates the ideal position of BAN devices on the spectrum of power versus data rate.

The variability among BAN devices in bandwidth and power consumption is evident. To ensure consistent behavior across devices while accommodating a wide range of functionalities, the BAN draft requirements establish a common set of standards for all devices.

• Healthcare Applications

BANs, an evolution of BSNs, hold their strongest applications in the healthcare field. Stefan Drude, a Philips researcher, summarized the potential uses of very low BSN devices. These devices, confined to a smaller range (< 0.01 - 2.00 m), tap into various aspects of the human body. Leveraging the body as a channel for short-range communication eliminates the need for traditional antennas, slashing BSN device power consumption to 0.1 - 1.0 mW. At this level, the human body can produce surplus energy for the devices to harvest directly, sidestepping reliance on conventional power sources like batteries [IEEE-BAN-SUMMARY]. This application isn't unique to Drude's group; Microsoft's patent, "Method and apparatus for transmitting power and data using the human body," has outlined a similar scenario.

Advanced Functionalities of BAN

In the subsequent sections, we delve into systems using BSN technology for advanced functionalities.

• Managed Body Sensor Networks (MBSN)

MBSNs involve a third party making decisions based on data collected from one or multiple BSNs. MobiHealth and CodeBlue represent two managed BSN approaches.

The MobiHealth approach, introduced by researchers at the University of Twente in 2003, catered to the rising demand for out-patient monitoring. This BSN, equipped with EBAN connectivity to 2.5/3G networks, facilitated remote monitoring of patient's vital signs, enabling multiple patients' data to be monitored collectively [Konstantas03].

Harvard University's CodeBlue, still in trial stages, offers a middleware-based approach. Unlike MobiHealth's packaged solution, CodeBlue provides flexibility at runtime, catering to different requirements like an emergency response or monitoring limb movement in stroke patient rehabilitation [CodeBlue06].

• Autonomous Body Sensor Networks (ABSN)

ABSNs, sharing goals with MBSNs, take a proactive approach by integrating actuators and intelligent sensors. Human++, a Belgian project, aims to mainstream ABSNs. Its design enables any node in the mesh network to communicate with a designated central node for EBAN communication and service access.

Let us consider a case study of cardiac monitoring for further information:

Case Study: Cardiac Monitoring

A case study by Zheng et al. in 2007 highlighted a MobiHealth-based cardiac monitoring system. Integrating GPS for precise patient location tracking, the system aimed for continuous vital sign monitoring for cardiovascular patients. Using a wearable smart fabric, "Wearable Shirt," the system allowed wireless sensor communication while being durable for everyday use. The system also incorporated online diagnosis and varying levels of local alarms, integrating ABSN features for selective event notifications.

Future Work

Future work in the body area network stream could be an important part of improving WBAN, focusing on how signals travel and how radio wires work close to the body. This helps determine how long it takes for signals to travel and by how much they are weakened between different focuses in the body.

Conclusion

In summary, this topic provides an overview of the development of BAN technology, applications in healthcare, case studies and challenges, emphasizing the growing importance of BANs in revolutionizing healthcare.