Wearable Biosensor

Recent advancements in miniature devices have fostered a dramatic growth of interest of wearable technology. Wearable Bio-Sensors (WBS) will permit continuous cardiovascular (CV) monitoring in a number of novel settings. WBS could play an important role in the wireless surveillance of people during hazardous operations (military, firefighting, etc) or such sensors could be dispensed during a mass civilian casualty occurrence. They typically rely on wireless, miniature sensors enclosed in ring or a shirt. They take advantage of handheld units to temporarily store physiological data and then periodically upload that data to a database server via wireless LAN or a cradle that allow Internet connection and used for clinical diagnosis.

 Wearable sensors and systems have evolved to the point that they can be considered ready for clinical application. The use of wearable monitoring devices that allow continuous or intermittent monitoring of physiological signals is critical for the advancement of both the diagnosis as well as treatment of diseases.

Wearable systems are totally non-obtrusive devices that allow physicians to overcome the limitations of ambulatory technology and provide a response to the need for monitoring individuals over weeks or months. They typically rely on wireless miniature sensors enclosed in patches or bandages or in items that can be worn, such as ring or shirt. The data sets recorded using these systems are then processed to detect events predictive of possible worsening of the patient’s clinical situations or they are explored to access the impact of clinical interventions. 


The LEDs and PD are placed on the flanks of the finger either reflective or transmittal type can be used. For avoiding motion disturbances quite stable transmittal method is used. Transmittal type has a powerful LED for transmitting light across the finger. This power consumption problem can be solved with a light modulation technique using high-speed devices. Instead of lighting the skiing continuously, the LED is turned ON only for a short time, say 10-100 ns, and the signal is sampled within this period, high frequency, low duty rate modulation is used for preventing skin-burning problem.

The motion of the finger can be measure with an optical sensor. This motion detector can be used not only for monitoring the presence of motion but also for cencelling the noise. By using PD-B as a noise reference, a noise cencellation filter can be built to eliminate the noise of PD-A that completes with the noise references used. And adaptive noise cancellation method is used.


The ring sensor and smart shirt are an effective and comfortable, and mobile information infrastructure that can be made to the individual’s requirements to take advantage of the advancements in telemedicine and information processing. Just as special-purpose chips and processors can be plugged into a computer motherboard to obtain the required information processing capability, the smart shirt is an information infrastructure into which the wearer can “plug in” the desired sensors and devices, thereby creating a system for monitoring vital signs in an efficient and cost effective manner with the “universal“ interface of clothing.

Advanced technologies such as the smart shirt have at partial to dramatically alter its landscape of healthcare delivery and at practice of medicine as we know them today. By enhancing the quality of life, minimizing “medical” errors, and reducing healthcare costs, the patient-control wearable information infrastructure can play a vital role in realizing the future healthcare system. Just as the spreadsheet pioneered the field of information processing that brought “computing to the masses”. It is anticipated that the smart shirt will bring personalized and affordable healthcare monitoring to the population at large, thus leading to the realization of “Affordable Healthcare, Any place, Anytime, Anyone”.