Minimising distance ambiguity through thresholding RSS measurements in wireless sensor networks

Making distance measurements with RSS can be challenging in indoor environments. The effect of multipath and shadowing introduces ambiguity into the readings, leading to a range of distances that can be inferred from a single measurement. This contribution highlights the frequency dependancy of these effects. Lower and upper bounding constraints are introduced to achieve an practical operational range and mitigate the possibility of ambiguous RSS measurements. In the results section we verify our theoretical limits with practical based experimental results. We also highlight the gains in RMSE when our thresholding approach is transferred to a localisation scheme.