Bounds on Distributed TDOA-Based Localization of OFDM Sources

摘要

One main drawback of using Time Difference of Arrival (TDOA) methods for source localization and navigation is that they require centralization of multiple copies of a signal. This paper considers blindly estimating the location of a Cyclic Prefix (CP) in an Orthogonal Frequency Division Multiplexing (OFDM) signal, enabling distributed TDOA computation up to an integer ambiguity. This ambiguity can be resolved using integer least-squares methods, if enough TDOAs are available. The contributions of this paper are derivation of the Cramer-Rao Lower Bound (CRLB) on locating the CP, and hence on the underlying source localization problem.