A review on green communication for wearable and implantable wireless body area networks

In the interconnected world, where wearable devices and implantable sensors have become integral to healthcare, Wireless Body Area Networks (WBANs) play a very pivotal role. These networks enable continuous monitoring of vital signs, early detection of health issues, and personalized patient care. However, ensuring the longevity and reliability of WBANs remains a multifaceted challenge. This comprehensive survey addresses this challenge by providing key insights and practical solutions. We investigate the intricacies of indoor communication links within WBANs, characterizing wireless channels thereby revealing factors that influence the quality of the received signal. By understanding multipath propagation, small-scale fading, and interference, we empower engineers to optimize communication protocols for reliable data transmission. In particular, we describe practical path loss models that have been successfully implemented in real-world WBANs. These models account for indoor scenarios, considering floor attenuation, wall partitions, and other environmental factors. Furthermore, we explore diverse energy harvesting (EH) techniques, from converting body movements to electrical energy to harnessing ambient RF signals. By addressing energy efficiency challenges, we extend the lifespan of WBAN devices, benefiting both patients and healthcare providers. We have also demonstrated the feasibility of incorporating EH into WBANs, via three case studies showcasing real-world validation. Finally, as the field evolves, we highlight open research problems, inviting further investigation into efficient wireless communication, seamless integration of EH techniques, and novel protocols for WBANs. In summary, this survey bridges theory and practice, fostering advancements in WBAN technology. By addressing wireless indoor channel modeling, energy efficiency, and their practical implementation in BAN, we contribute to the effectiveness of WBANs in indoor scenarios.