Backscatter communication is expected to help in revitalizing the domain of healthcare through its myriad applications. From on-body sensors to in-body implants and miniature embeddable devices, there are many potential use cases that can leverage the miniature and low-powered nature of backscatter devices. However, the existing literature lacks a comprehensive study that provides a distilled review of the latest studies on backscatter communications from the healthcare perspective. Thus, with the objective to promote the utility of backscatter communication in healthcare, this paper aims to identify specific applications of backscatter systems. A detailed taxonomy of recent studies and gap analysis for future research directions are provided in this work. Finally, we conduct measurements at 590 MHz in different propagation environments with the in-house designed backscatter device. The link budget results show the promise of backscatter devices to communicate over large distances for indoor environments which demonstrates its potential in the healthcare system.
Index TermsBackscatter communication, Healthcare, In-body implants, Link budget, On-body sensors
I. INTRODUCTIONThe medical industry today is seeking new solutions for in-body and on-body devices that transfer the data over a wireless channel [1], [2]. This includes pacemakers for generating electric pulses, micro-scale robots that operate in the bloodstream, and smart pills for identifying abnormalities in the gastrointestinal tract. However, the modern deep tissue systems consume a significant amount of energy by generating their own radio signals. For instance, wireless capsules for endoscopy consume up to 10 times more power than the sensors [1]. Due to these reasons, the large battery of the capsule consumes 40-50% of the total space of the capsule [2]. Reduction in this form-factor (i.e., the size, shape, and other physical specifications of electronic components) of these capsules can not only improve the likelihood of completion of endoscopy but also make them easy to swallow and excrete. Similar challenges are faced in the case of on-body sensors. The premise of on-body sensor networks is to build a network of devices capable of operating in a battery-free manner by means of smart networking, and power management at the granularity of individual bits and instructions. This is challenging to achieve through conventional networking approaches due to the need for active radio circuits, large form-factors, and their energy constraint nature. Thus, we expect that it is important to divorce the healthcare from conventional wireless solutions and move towards innovative systems for seamlessly connecting the in-body and on-body wireless devices.Backscatter communication is an emerging paradigm and a key enabler for pervasive connectivity of low-powered wireless devices [3]. It is primarily beneficial in situations where computing and connectivity capabilities expand to sensors and miniature devices that exchange data on a low power budget. Due to this in...