Tom Ahola

Wearable FPGA Based Wireless Sensor Platform

A new wearable sensor platform has been developed. It is based on a Field Programmable Gate Array (FPGA) device. Because of this the hardware is very flexible and gives the platform unique opportunities for research of a wide range of architectures, applications and signal processing algorithms. The platform has been named NWSP, for Nokia Wrist-Attached Sensor Platform. This document describes the hardware, the firmware and applications of the platform.

Pedometer for Running Activity Using Accelerometer Sensors on the Wrist

The Nokia Wrist–Attached Sensor Platform (NWSP) was developed at the Nokia Research Center during the NUADU project to facilitate research and demonstrations of use cases of wearable wireless sensors. A wrist–worn pedometer application was implemented as one of the demonstrations of the capabilities of the platform. In this paper the step counting algorithm is described and the performance is evaluated. The application is targeted for running exercise. However, the detection of steps during walking is also discussed.

Considerations for Synchronization in Body Area Networks for Human Activity Monitoring

In this paper, we highlight considerations for synchronization issues in body area networks. Requirements for the synchronization accuracy in body area networks depend on the application at hand. Synchronization may be needed for power management, sample ordering, calculation of stimulus responses and for sensor fusion. This paper provides a theoretical exercise to help understand the accuracy required for typical human motion sensing. It gives an overview of various synchronisation strategies used and implemented in prototype systems. Lessons learnt from practical implementations using Bluetooth, an IEEE 802.15.4 proprietary network and Nanonet are presented to illustrate the principles involved. The discussion provides some considerations and the requirements for typical WBAN applications.