In this letter, we consider the privacy-preserving strategies of the
distributed state estimator over wireless sensor networks. Aiming at an
eavesdropper who can intercept the data transmitted on the communication
channel, we design a simple preserving scheme to encode the transmitted
data by using system dynamics and history estimates. To analyze the
privacy-preserving performance, we use the gap between the values
deciphered by the eavesdropper and decoded by the sensor as the privacy
index to evaluate the degree of robust privacy protection. Finally, we
provide some simulations to illustrate the effectiveness of the proposed
preserving schemes.