Preventing Hostile TOA/TDOA Localization With AF Relay

This letter proposes a relay-assisted transmission scheme to protect the source location privacy (SLP) against hostile localization based on time of arrival (TOA) or time difference of arrival (TDOA) estimation. To avoid being located, the source first transmits with small power, and then the signal is amplified by the relay node. The adversary’s localization error bounds are derived, and the optimization problem to maximize the destination’s received signal-to-noise ratio (SNR) is solved. The numerical results depict the effectiveness of the proposed scheme by showing that it achieves the required SLP with an acceptable loss in communication performance.