Understanding the Real Behavior of Mote and 802.11 Ad Hoc Networks: An Experimental Approach

IEEE 802.11 and Mote devices are today two of the most interesting wireless technologies for ad hoc and sensor networks respectively, and many efforts are currently devoted to understanding their potentialities. Unfortunately, few works adopt an experimental approach, though several papers highlight that popular simulation and analytical approximations may lead to very inaccurate results. In this paper we discuss outcomes from an extensive measurement study focused on these technologies. We analyze the dependence of the communication range on several parameters, such as node distance from the ground, transmission data rate, environment humidity. Then, we study the extent of the physical carrier sensing zone around a sending node. On the basis of these elements, we provide a unified wireless link model for both technologies. Finally, by using this model we analyze well-known scenarios (such as the hidden node problem), and we modify the traditional formulations according to our experimental results.