DETECTING SIGNAL MODULATION FOR MOTION DETECTION

In a general aspect, motion is detected based on wireless signals. In some aspects, a modulation type of a first signal is identified at a motion detector device. The first signal is based on a wireless signal transmitted through a space by a transmitter device and received by the motion detector device. A demodulator at the motion detector device generates a second signal from the first signal by demodulating the first signal according to the identified modulation type. A modulator at the motion detector device generates a third signal from the second signal by modulating the second signal according to the identified modulation type. A channel response is generated based on the first signal and the third signal. The channel response is used to detect motion of an object in the space.