Cramér rao lower bound for underwater range estimation with noisy sound speed profile
نویسندگان
چکیده
In this paper, the Cramér Rao bound (CRB) for range estimate between two underwater nodes is calculated. The nodes are equipped with Conductivity-Temperature-Density (CTD) sensors to measure their depths, and the sound speed at different depths, and an acoustic modem to measure their mutual time of flight. The measurement noise is assumed to be Gaussian distributed. We show how much the CRB gets affected by each measurement noise. For long distances, the effect of sound speed measurement noise is dominant, and its impact depends on the actual sound speed profile, the depths at which the sound speed samples are gathered, and the number of samples.
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