Designing a New Link Quality Estimator for Sensor Nodes by Combining Available Estimators

The efficiency and reliability of wireless network mainly depends upon the delivery power of its links. So it is important to measure which link is more reliable and can deliver data effectively over a long period of time. We study the quality of a link based on the available estimators mainly the Packet Reception Rate (PRR), the Received Signal Strength Indicator (RSSI), the Signal to Noise Ratio (SNR) of the CC2420 radio in a purely software based environment. Each one of them has some shortcomings. The result also is not very obvious as different estimators show different links to be better than others. This leads us to design a new LQ metric which would not only come up with better result but also reflect the sudden changes of the quality of the links.