868 MHz: A Noiseless Environment, But No Free Lunch for Protocol Design
Lossy links are one of the fundamental characteristics of Wireless Sensor Networks (WSNs). A large amount of work has been performed on characterizing link properties of 802.15.4 radios, in particular in the 2.4GHz band. Unfortunately, the 2.4 GHz band has the apparent disadvantage of a crowded spectrum and considerable external interference, e.g., from WiFi, Bluetooth or even microwave ovens. The authors, therefore, investigate the performance of radios operating on the alternative 868MHz frequency band, which is basically noise-free as determined from extensive experiments on a large-scale indoor testbed featuring more than 100 nodes.