Wireless Sensing Privacy Protection via Multi-Carrier Chirp Waveform

Due to the wide applications of wireless sensing technology, sensing privacy is becoming more and more important. In this paper, we propose a sensing privacy protection approach, in which we use multi-carrier chirp (MCC) signal waveform to modulate sensing sequence. This waveform has adjustable parameters and we take them as secret parameters to protect users' sensing privacy. To show the idea more clearly, we consider the case of moving speed sensing in the application of smart home. On the one hand, we demonstrate the shortcomings of the approach adopted in IEEE 802.11az standard in terms of sensing performance and privacy protection performance; On the other hand, we analyze the advantages of using MCC signal waveform. When the waveform parameters are kept secret from the eavesdroppers, they cannot estimate the channel correctly and thus user's privacy of speed information is protected. Simulations show that the approach not only can protect the privacy of speed information, but also has a better sensing performance, which has a lower mean square error (MSE) of speed estimation.