Received signal strength (RSS) can be used in sensor networks as a ranging measurement for positioning and\r\nlocalization applications. This contribution studies the realistic situation where neither the emitted power nor the\r\npower law decay exponent be assumed to be known. The application in mind is a rapidly deployed network\r\nconsisting of a number of sensor nodes with low-bandwidth communication, each node measuring RSS of signals\r\ntraveled through air (microphones) and ground (geophones). The first contribution concerns validation of a model\r\nin logarithmic scale, that is, linear in the unknown nuisance parameters (emitted power and power loss constant).\r\nThe parameter variation is studied over time and space. The second contribution is a localization algorithm based\r\non this model, where the separable least squares principle is applied to the non-linear least squares (NLS) cost\r\nfunction, after which a cost function of only the unknown position is obtained. Results from field trials are\r\npresented to illustrate the method, together with fundamental performance bounds. The ambition is to pave the\r\nway for sensor configuration design and more thorough performance evaluations as well as filtering and target\r\ntracking aspects.
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