Cognitive Systems Corp.

Christopher Beg

Mohammad Omer

Tajinder Manku

William Halford

Paul Lock

In a general aspect, various fields of a PHY frame are used for motion detection. In some aspects, a first training field and a second, different training field are identified in a PHY frame of each wireless signal transmitted between wireless communication devices in a wireless communication network. A first time-domain channel estimate and a second time-domain channel estimate are generated for each wireless signal. The first time-domain channel estimate is based on a first frequency-domain signal included in the first training field, while the second time-domain channel estimate is based on a second frequency-domain signal included in the second training field. A determination is made whether motion has occurred in a space during the time period based on the first time-domain channel estimates, and a location of the motion within the space is determined based on the second time-domain channel estimates.

Using MIMO training fields for motion detection

In a general aspect, motion is detected in an environment using wireless signals. In one example, a downlink high-efficiency PHY (HE-PHY) frame is received. The downlink HE-PHY frame is transmitted by an access point device to wireless communication devices residing inside an environment. An uplink orthogonal frequency-division multiple access (UL-OFDMA) transmission is subsequently received in response to the downlink HE-PHY frame. The UL-OFDMA transmission is transmitted by the wireless communication devices to the access point device. The UL-OFDMA transmission includes uplink HE-PHY frames simultaneously transmitted on respective resource units by the respective wireless communication devices. A motion data set is generated based on channel responses computed from the uplink HE-PHY frames. Each channel response is computed from a respective one of the uplink HE-PHY frames. Motion within the environment is analyzed based on the motion data set.

Using high-efficiency PHY frames for motion detection

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.

Controlling device participation in wireless sensing systems

A method includes receiving a ground-truth motion indication from a measurement device. The ground-truth motion indication is a time series of locations and a corresponding indication of a motion state at each location of the time series of locations. The method also includes receiving a time series of detected motion states based on wireless signals communicated through a space over a time period by a wireless communication network comprising a plurality of wireless communication devices. The detected motion states for a time interval within the time series are compared to the ground-truth motion indication for the time interval within the time series to generate a time series of consistency scores. The consistency scores are processed to produce an aggregate motion-detection capability score at each location. The method also includes providing, for display as a graphical representation of motion-detection capability within the space, the aggregate motion-detection capability at each location.

Analyzing Wi-Fi motion coverage in an environment

In a general aspect, a rate at which MIMO transmissions are elicited from wireless communication devices is varied. A first wireless communication device may be configured to wirelessly transmit a first set of messages at a first transmission rate to a second wireless communication device. The first wireless communication device may further be configured to receive MIMO transmissions from the second wireless communication device. The first wireless communication device may additionally be configured to generate first channel information based on respective training fields in each of the first MIMO transmissions; determine a rate at which the first channel information is generated; vary the first transmission rate to a second, different transmission rate based on the rate at which the first channel information is generated; and wirelessly transmit a second set of messages at the second transmission rate to the second wireless communication device.

Varying a rate of eliciting MIMO transmissions from wireless communication devices

In a general aspect, a motion sensing topology of a multi-access point (multi-AP) wireless communication network can be controlled. In some aspects, the multi-AP wireless communication network includes a first AP device, a second AP device, and a multi-AP controller. The multi-AP controller identifies a wireless communication topology, which includes identifying that a first client station device is associated with the first AP device. The multi-AP controller defines a motion sensing topology that is different from the wireless communication topology, and the motion sensing topology includes a wireless motion sensing link between the first client station device and the second AP device. The multi-AP controller initiates a motion sensing measurement based on the motion sensing topology, and the motion sensing measurement uses the wireless motion sensing link while the first client station device remains associated with the first AP device.

Controlling motion topology in a standardized wireless communication network

In a general aspect, MIMO transmissions are elicited from wireless communication devices for wireless sensing. A first wireless communication device may be configured to generate network or transport layer messages addressed to a second wireless communication device in a wireless communication network, and wirelessly transmit the network or transport layer messages to the second wireless communication device to elicit MIMO transmissions from the second wireless communication device. The first wireless communication device may further be configured to receive MIMO transmissions from the second wireless communication device, where the MIMO transmissions traverse a space between the first wireless communication device and the second wireless communication device. The first wireless communication device may additionally be configured to identify a training field in each MIMO transmission, generate channel information based on the respective training fields, and detect motion that occurred in the space based on the channel information.

Eliciting MIMO transmissions from wireless communication devices

In a general aspect, motion is passively detected in an environment using wireless signals. In one example, a wireless sensor device that resides outside an environment receives wireless signals transmitted by wireless communication devices that reside inside the environment. One or more sets of motion data are generated, each having a corresponding set of link identifiers. The one or more sets of motion data may be based on beamforming reports in a first subset of the wireless signals and on physical (PHY) frames in a second subset of the wireless signals. The corresponding set of link identifiers may be based on address information in the first and second subsets of the wireless signals. A combined motion data set including the one or more sets of motion data is generated, and motion within the environment is analyzed based on the combined motion data set.

Using over-the-air signals for passive motion detection

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.

Controlling measurement rates in wireless sensing systems

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. The method further includes receiving second motion detection output data representing a degree of motion detected by the wireless sensing system after the characteristic of the first wireless communication link has changed in response to the first control signal.

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Kitchener, Canada

Christopher Beg