Bluetooth Low Energy, Zigbee, and cognitive 3D-ICs add muscle to telehealth

With one seventh of the world's population overweight and an elderly population expected to double to 1.2 billion by 2025, healthcare expenditures in developed countries are exploding. This situation, compounded by the scarcity of qualified medical personnel (general practitioners, nurses, etc.), and an at-stake tax base as the first baby boomers are about to retire, are fueling an increased demand for telehealth solutions. Through the remote collection and regular transfer of physiological parameters, telehealth can be seen as a tool of increased productivity and quality of care since it has the potential to help improve physical fitness, reduce the cost of chronic disease management, and allow elderly people to remain living in their own home.

The Continua Health Alliance, an industry consortium promoting telehealth and guaranteeing end-to-end interoperability from sensors to health record databases, has defined in its version 1.5 design guidelines, a dual interface for communication with physiological and residential sensors (See Figure 1) showing a Personal Area Network (PAN) interface based on the recently approved Bluetooth Low Energy (BLE) standard and its health device profiles, and a Local Area Network (LAN) interface, based on the Zigbee Health Care application profile. Both standards are relatively similar in terms of complexity but BLE, as it name implies, tends to have a longer battery life primarily due to the use of short packet overhead and faster data rates, reduced number of packet exchanges for a short discovery/connect time, and skipped communication events, while Zigbee benefits from a longer range and better reliability with the use of a robust modulation scheme (Direct Sequence Spread Spectrum with orthogonal coding [32,4]) and a mesh-like clustered star networking technology.

Figure 1:  Continua Health Alliance PAN and LAN interfaces (v1.5)

Both interfaces are well adapted to their respective usage context, from on-the-move on one hand to home use or assisted care facilities on the other, but the flip side to that coin is that the Continua dual interface concept is likely to cause user frustration given the lack of interoperability between the two specifications, which negatively impacts the wide adoption of telehealth systems. There are also many end-user scenarios that could benefit from the support of both standards with the end-goal of either enhancing user experience or improving health risk detection. For example,