Using the electromagnetic spectrum

We consider the problem of estimating the power and position of an unknown transmitter using only observations on the received power for several sensors, without any directional information. We describe several existing propagation models, and we compute the Fisher in- formation for the free-space loss model. For more complex model, we present some results using a Markov Chain Monte Carlo method, and we describe the application of a particle filter to estimate posterior distributions for the transmitter and channel characteristics.