An Experimental Study on IEEE 802.15.4 Multichannel Transmission to Improve RSSI-Based Service Performance

In Wireless Sensor Networks (WSNs) the majority of the devices provide access to the Received Signal Strength Indicator (RSSI), which has been used as a means to enable different services and applications like localization, geographic routing and link quality estimation. Notwithstanding the popularity of using RSSI for localization, academic research showed that RSSI-based distance estimate is rather unreliable due to the random attenuation experienced by the radio signals, as the multipath fading. In this paper we propose a simple way to improve the RSSI reliability, averaging samples collected at different frequencies by a CC2420 radio, which implements the IEEE 802.15.4 standard, both in real indoor and outdoor scenarios. For this purpose, we introduce a simple communication protocol to coordinate data exchange between nodes, that exploits multichannel transmission in order to mitigate the multipath effect that hampers ranging estimation as well as wireless communication.