  Device-free wireless sensing attracts enormous attentions since it senses the
environment without additional devices. While cellular signals are good
opportunistic radio sources, the influence of inter-cell interference (ICI) on
wireless sensing has not been adequately addressed. In this letter, we first
investigate the cause of ICI and its impact on wireless sensing. Then we
propose an ICI-free channel estimation method by reconstructing the broadcast
signals of adjacent cells and solving simultaneous equations. Wireless gesture
recognition can be greatly benefited by ICI mitigation. Finally, we build a
prototype system to receive the commercial 4G-LTE signals, and demonstrate the
accuracies of wireless gesture recognition under various conditions.
