Enhancing RSSI-based Tracking Accuracy in Wireless Sensor

Networks

Bracha HodBracha HodBased on a joint work with: Based on a joint work with:

Gaddi Blumrosen, Dr. Tal Anker, Gaddi Blumrosen, Dr. Tal Anker, Prof. Danny Dolev and Prof. Boris Prof. Danny Dolev and Prof. Boris

RubinskyRubinsky

Motivation Precise tracking systems in an indoor

environment are important in many fields, such as sports and medicine

Wireless sensor networks can provide motion and location tracking

RSSI-based Tracking RSSI (Received Signal Strength

Indicator) is a measurement of the signal power on a radio link

RSSI-based tracking includes two steps Range estimation between pairs of nodes

based on RSSI measurements Location estimation using geometric or

statistical methods applied on the information from all nodes

Simple and cheap, widely used, low-power consumption, and not suffer from any drift

Contribution Existing RSSI-based tracking systems

provide a tracking accuracy in the scale of a meter Variations in the wireless medium,

reflections, scatterers, multi-paths interference

Our RSSI-based tracking system achieves an accuracy in the order of a few centimeters Close-proximity High transmission rate

Setup The mobile node transmits data

packets The static sensor nodes receive

packets from the mobile node and calculate the RSSI

The computer processes the information and estimates the mobile node’s location

Close-proximity

Spatial-Temporal Correlation

Interpolation Low-pass filter

Spatial-Temporal Correlation

Before post-processing After median filter

After low-pass filter

High Transmission Rate

Error Analysis

Summary We proposed a new RSSI-based

tracking system that achieves a high accuracy Close-proximity High transmission rate

Future work Integration of RSSI measurements

with other motion sensors More extensive experiments

Thank You!