Abstract: In a general aspect, motion is detected using wireless signals. In an example, a method includes receiving, at a wireless communication device, requests for the wireless communication device to transmit wireless signals, the requests initiated by a wireless sensing system. The method further includes transmitting a series of wireless signals from the wireless communication device in response to the requests, and detecting, at the wireless communication device, a trigger event after transmitting the series of wireless signals. The method additionally includes updating, by the wireless communication device, a state of the wireless communication device based on the trigger event, the updated state indicating that the wireless communication device is not enabled to transmit wireless signals in response to the requests from the wireless sensing system. The method also includes communicating, by the wireless communication device, the updated state of the wireless communication device to the wireless sensing system.

Abstract: In a general aspect of the examples described, motion is detected based on bi-directional channel sounding. In an example, a first set of channel information is obtained from a first device. The first set of channel information is based on a first set of wireless signals transmitted from a second device through a space at a first time in a timeframe. A second set of channel information is obtained from the second device. The second set of channel information is based on a second set of wireless signals transmitted from the first device through the space at a second time in the timeframe. The first and second sets of channel information are analyzed to detect a category of motion or a location of detected motion in the space during the timeframe.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, a method includes receiving, at a wireless communication device, requests for the wireless communication device to transmit wireless signals, the requests initiated by a wireless sensing system. The method further includes transmitting a series of wireless signals from the wireless communication device in response to the requests, and detecting, at the wireless communication device, a trigger event after transmitting the series of wireless signals. The method additionally includes updating, by the wireless communication device, a state of the wireless communication device based on the trigger event, the updated state indicating that the wireless communication device is not enabled to transmit wireless signals in response to the requests from the wireless sensing system. The method also includes communicating, by the wireless communication device, the updated state of the wireless communication device to the wireless sensing system.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, a method includes receiving, at a wireless communication device, requests for the wireless communication device to transmit wireless signals, the requests initiated by a wireless sensing system. The method further includes transmitting a series of wireless signals from the wireless communication device in response to the requests, and detecting, at the wireless communication device, a trigger event after transmitting the series of wireless signals. The method additionally includes updating, by the wireless communication device, a state of the wireless communication device based on the trigger event, the updated state indicating that the wireless communication device is not enabled to transmit wireless signals in response to the requests from the wireless sensing system. The method also includes communicating, by the wireless communication device, the updated state of the wireless communication device to the wireless sensing system.

Abstract: In a general aspect of the examples described, motion is detected based on bi-directional channel sounding. In an example, a first set of channel information is obtained from a first device. The first set of channel information is based on a first set of wireless signals transmitted from a second device through a space at a first time in a timeframe. A second set of channel information is obtained from the second device. The second set of channel information is based on a second set of wireless signals transmitted from the first device through the space at a second time in the timeframe. The first and second sets of channel information are analyzed to detect a category of motion or a location of detected motion in the space during the timeframe.

Abstract: In a general aspect of the examples described, motion is detected based on bi-directional channel sounding. In an example, a first set of channel information is obtained from a first device. The first set of channel information is based on a first set of wireless signals transmitted from a second device through a space at a first time in a timeframe. A second set of channel information is obtained from the second device. The second set of channel information is based on a second set of wireless signals transmitted from the first device through the space at a second time in the timeframe. The first and second sets of channel information are analyzed to detect a category of motion or a location of detected motion in the space during the timeframe.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, in response to a first series of sampling instructions asserted at a first sampling rate in a wireless sensing system, a first series of requests is sent for a wireless communication device to transmit a first series of wireless signals. The first series of wireless signals is received and motion detection output data is obtained based on the first series of wireless signals. A rate at which sampling instructions are asserted is changed from the first sampling rate to a second, different sampling rate based on the motion detection output data. In response to a second series of sampling instructions asserted at the second sampling rate in the wireless sensing system, a second series of requests is sent for the wireless communication device to transmit a second series of wireless signals.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, a method includes receiving, at a wireless communication device, requests for the wireless communication device to transmit wireless signals, the requests initiated by a wireless sensing system. The method further includes transmitting a series of wireless signals from the wireless communication device in response to the requests, and detecting, at the wireless communication device, a trigger event after transmitting the series of wireless signals. The method additionally includes updating, by the wireless communication device, a state of the wireless communication device based on the trigger event, the updated state indicating that the wireless communication device is not enabled to transmit wireless signals in response to the requests from the wireless sensing system. The method also includes communicating, by the wireless communication device, the updated state of the wireless communication device to the wireless sensing system.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, in response to a first series of sampling instructions asserted at a first sampling rate in a wireless sensing system, a first series of requests is sent for a wireless communication device to transmit a first series of wireless signals. The first series of wireless signals is received and motion detection output data is obtained based on the first series of wireless signals. A rate at which sampling instructions are asserted is changed from the first sampling rate to a second, different sampling rate based on the motion detection output data. In response to a second series of sampling instructions asserted at the second sampling rate in the wireless sensing system, a second series of requests is sent for the wireless communication device to transmit a second series of wireless signals.

Abstract: In a general aspect, motion is detected using wireless signals. In an example, a method includes receiving first motion detection output data representing a degree of motion detected by a wireless sensing system based on wireless signals exchanged in a wireless communication network. The wireless communication network includes a first access point device and a first client device communicatively coupled by a first wireless communication link. The method also includes receiving network information indicative of a network topology of the wireless communication network, and generating a first control signal configured to change a characteristic of the first wireless communication link based on the first motion detection output data and network information.

Abstract: In a general aspect, motion is detected using wireless signals. In one example, a wireless signal transmitted through a space from a first wireless communication device is received at a second wireless communication device. Dynamic beamforming information is based on the wireless signal. The second wireless communication device uses the dynamic beamforming information to detect motion in the space, or transmits the dynamic beamforming information to the first wireless communication device for use in detecting motion in the space.

Abstract: In a general aspect, motion is detected using wireless signals. In one example, a wireless standard protocol message is transmitted by a wireless communication device through a space to one or more neighbor devices. A corresponding wireless standard protocol response including beamforming information feedback is received from each of the one or more neighbor devices in response to the wireless standard protocol message. Motion of an object in the space is detected based on the beamforming information feedback from each of the neighbor devices.

Abstract: In a general aspect, a sensitivity setting is adjusted in a motion detection system. In some aspects, a user interface is provided by a motion detection system, and user input data is obtained through the user interface. A wireless communication link is identified based on the user input data; the wireless communication link is provided by a first wireless communication device and a second wireless communication device. Based on the user input data, a value is assigned to a sensitivity setting associated with the wireless communication link in the motion detection system. The motion detection system obtains data for motion detection based on wireless signals communicated through a space on the wireless communication link. Motion of an object in the space is detected based on the data and the value of the sensitivity setting.

Abstract: A transmission apparatus for a wireless device, comprising: an antenna for receiving an original signal and for backscattering a modulated signal containing information from the wireless device; a variable impedance coupled to the antenna, the variable impedance having an impedance value; a delta-sigma modulator coupled to the variable impedance for modulating the impedance value, and thereby a backscattering coefficient for the antenna, in accordance with the information to generate the modulated signal; and, a decoder coupled to the delta-sigma modulator for generating the impedance value from the information.

Abstract: In a general aspect of the examples described, motion is detected based on bi-directional channel sounding. In an example, a first set of channel information is obtained from a first device. The first set of channel information is based on a first set of wireless signals transmitted from a second device through a space at a first time in a timeframe. A second set of channel information is obtained from the second device. The second set of channel information is based on a second set of wireless signals transmitted from the first device through the space at a second time in the timeframe. The first and second sets of channel information are analyzed to detect a category of motion or a location of detected motion in the space during the timeframe.

Abstract: In a general aspect, motion is detected using wireless signals. In one example, a wireless standard protocol message is transmitted by a wireless communication device through a space to one or more neighbor devices. A corresponding wireless standard protocol response including beamforming information feedback is received from each of the one or more neighbor devices in response to the wireless standard protocol message. Motion of an object in the space is detected based on the beamforming information feedback from each of the neighbor devices.

Abstract: In a general aspect, motion is detected using wireless signals. In one example, a wireless signal transmitted through a space from a first wireless communication device is received at a second wireless communication device. Dynamic beamforming information is based on the wireless signal. The second wireless communication device uses the dynamic beamforming information to detect motion in the space, or transmits the dynamic beamforming information to the first wireless communication device for use in detecting motion in the space.

Abstract: In a general aspect of the examples described, motion is detected based on received wireless signals in a mesh network. In an example, transfer function components for each pair of devices are obtained. A time series of transfer function matrices is generated, with each of the transfer function matrices comprising a respective subset of the transfer function components. Motion of an object in the space is detected based on the time series of transfer function matrices.

Abstract: A transmission apparatus for a wireless device, comprising: an antenna for receiving an original signal and for backscattering a modulated signal containing information from the wireless device; a variable impedance coupled to the antenna, the variable impedance having an impedance value; a delta-sigma modulator coupled to the variable impedance for modulating the impedance value, and thereby a backscattering coefficient for the antenna, in accordance with the information to generate the modulated signal; and, a decoder coupled to the delta-sigma modulator for generating the impedance value from the information.

Abstract: In a general aspect, a motion detection channel is operated in a wireless communication network. In some aspects, a first wireless network device communicates wireless network traffic on a first subset of wireless communication channels in a wireless communication network. The first wireless network device receives motion detection signals transmitted through a space by a second wireless network device. The motion detection signals are received on a second subset of wireless communication channels. The motion detection signals are processed to detect motion of an object in the space.