Detect presence based on wireless signal analysis

Abstract

In a general aspect, a monitoring system detects the presence of an object in a space, for example, without detecting motion. The motion of the object in the space is detected by analyzing a first signal set based on wireless signals transmitted in a first time period. The absence of motion in the space is detected by analyzing a second signal set based on wireless signals transmitted in a subsequent second time period. The presence of an object in the space during the second time period is detected by analyzing the second signal set.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Application No. 15 / 935,972, filed on March 26, 2018, entitled “Detecting Presence Based on Wireless Signal Analysis,” the contents of which are incorporated herein by reference. Background Art

[0003] The following description relates to detecting the presence of an object in a space based on wireless signals.

[0004] Motion detection systems have been used to detect the movement of objects within a room or outdoor area, for example. In some exemplary motion detection systems, infrared or optical sensors are used to detect the movement of objects within the field of view of the sensor. Motion detection systems have been used in security systems, automated control systems, and other types of systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 is a diagram illustrating an exemplary wireless communication system.

[0006] Figures 2A to 2D is a diagram showing exemplary wireless signals communicated between wireless communication devices in a monitoring system.

[0007] Figure 3A-3B is a diagram illustrating exemplary wireless signals in occupied and unoccupied spaces.

[0008] Figure 4 is a block diagram showing an example of a channel state based on a wireless signal communicated between wireless communication devices.

[0009] Figure 5 is a flow chart illustrating an exemplary process for detecting the presence of an object in a space based on wireless signals.

[0010] Figure 6 is a block diagram illustrating an exemplary wireless communication device. DETAILED DESCRIPTION

[0011] As an overview, the monitoring system is configured to detect movement in the space based on changes in wireless signals sent through the space on a communication channel. For example, a person may enter or walk through the space, and the monitoring system can detect the movement of the person based on changes in the wireless signal. Subsequently, the monitoring system can stop detecting the movement of the person (e.g., detecting that there is no movement), such as when the wireless signal is not changing or is not changing enough to indicate movement. It is also advantageous to have a presence detection aspect of the monitoring system that can determine the presence of an object (e.g., a person) in the space, thereby determining whether the space is occupied, even if the motion detection aspect of the monitoring system cannot detect the movement of the object. It is also advantageous to determine whether the object (e.g., a person) is no longer present in the space. For example, it would be advantageous to let monitoring systems such as alarm systems, motion detection systems, protection systems, personal monitoring systems, etc. determine whether an intruder is in a residence, whether someone has fallen and needs help. In some cases, it may be advantageous to let an enterprise determine the occupancy of a room, building, or other space in other ways (such as power management of a house or property) in certain other situations. For example, light, air conditioning, heat, etc. can be adjusted for unoccupied parts of a building.

[0012] In some instances, aspects of the present invention may provide additional advantages. For example, the presence or absence of an object in a space where no motion is detected may be determined based on wireless signals without requiring line of sight between devices. In some cases, the presence or absence of an object where no motion is detected may be determined using features of existing wireless communication devices and networks. According to aspects of the present invention, the presence or absence of an object where no motion is detected may further improve the operation of monitoring and alarm systems to make them more accurate and useful in assessing the occurrence and accurately determining the condition of a space (e.g., occupied or unoccupied), and may also provide other technical improvements to the operation of monitoring and alarm systems.

[0013] In some aspects described herein, the presence or absence of objects in a space (eg, whether the space is occupied or unoccupied) where no motion is detected can be detected using information from multiple wireless communication devices communicating in the space.

[0014] For example, wireless signals received at each wireless communication device in a wireless communication network can be analyzed to determine the channel information of different communication links in the network (between the corresponding wireless communication device pairs in the network). Channel information can represent the physical medium to which the transfer function is applied to the wireless signal passing through the space. In some instances, the channel information includes channel response information. Channel response information can refer to the known channel characteristics of the communication link, and can describe how the wireless signal propagates from the transmitter to the receiver, thereby representing, for example, the combined effects of scattering, fading, and power attenuation in the space between the transmitter and the receiver. In some instances, the channel information includes beamforming state information. Beamforming (or spatial filtering) can refer to a signal processing technique used in a multi-antenna (multiple input / multiple output (MIMO)) radio system to perform directional signal transmission or reception. Beamforming can be achieved by combining elements in an antenna array in such a way that signals at a specific angle experience constructive interference and other signals experience destructive interference. Beamforming can be used at both the transmitting end and the receiving end to achieve spatial selectivity. In some cases (e.g., the IEEE 802.11ac standard), the transmitter uses a beamforming steering matrix. The beamforming steering matrix may include a mathematical description of how the antenna array should use its individual antenna elements to select a spatial path for transmission.Although certain aspects are described herein with respect to channel response information, beamforming state information or beamforming steering matrix states may also be used in the described aspects.

[0015] The channel information of each communication link may be analyzed (e.g., by a hub device or other device in the network or a remote device communicatively coupled to the network) to detect whether motion has occurred in the space, to determine the relative position of the detected motion, or both. In some aspects, the channel information of each communication link may be analyzed (e.g., when no motion is detected in the space) to detect whether an object is present or absent.

[0016] In some implementations, the wireless communication network may include a wireless mesh network. A wireless mesh network may refer to a decentralized wireless network whose nodes (e.g., wireless communication devices) communicate directly in a point-to-point manner without using a central access point, base station, or network controller. A wireless mesh network may include mesh clients, mesh routers, or mesh gateways. In some instances, the wireless mesh network is based on the IEEE 802.11s standard. In some instances, the wireless mesh network is based on Wi-Fi ad hoc or other standard technologies.

[0017] Figure 1An exemplary wireless communication system 100 is shown. The exemplary wireless communication system 100 includes three wireless communication devices - a first wireless communication device 102A, a second wireless communication device 102B, and a third wireless communication device 102C. The exemplary wireless communication system 100 may include additional wireless communication devices 102 and / or other components (e.g., one or more network servers, network routers, network switches, cables or other communication links, etc.).

[0018] The exemplary wireless communication devices 102A, 102B, 102C may, for example, operate in a wireless network in accordance with a wireless network standard or other type of wireless communication protocol. For example, a wireless network may be configured to operate as a wireless local area network (WLAN), a personal area network (PAN), a metropolitan area network (MAN), or other types of wireless networks. Examples of WLANs include networks configured to operate in accordance with one or more standards in the 802.11 family of standards developed by the IEEE (e.g., Wi-Fi networks), etc. Examples of PANs include networks configured to operate in accordance with short-range communication standards (e.g., A network that operates using near field communication (NFC), ZigBee, and millimeter wave communications.

[0019] In some implementations, the wireless communication devices 102A, 102B, 102C may be configured to communicate in a cellular network, for example, in accordance with a cellular network standard. Examples of cellular networks include networks configured in accordance with 2G standards such as Global System for Mobile (GSM) and Enhanced Data Rates for GSM Evolution (EDGE) or EGPRS; 3G standards such as Code Division Multiple Access (CDMA), Wideband Code Division Multiple Access (WCDMA), Universal Mobile Telecommunications System (UMTS), and Time Division Synchronous Code Division Multiple Access (TD-SCDMA); 4G standards such as Long Term Evolution (LTE) and Advanced LTE (LTE-A); and 5G standards, among others. Figure 1 In the example shown, the wireless communication devices 102A, 102B, 102C may be or may include standard wireless network components. For example, the wireless communication devices 102A, 102B, 102C may be commercially available Wi-Fi devices.

[0020] In some cases, the wireless communication devices 102A, 102B, 102C may be Wi-Fi access points or other types of wireless access points (WAPs). The wireless communication devices 102A, 102B, 102C may be configured to perform one or more operations as described herein as instructions (e.g., software or firmware) embedded on the wireless communication devices. In some cases, the wireless communication devices 102A, 102B, 102C may be nodes of a wireless mesh network such as a commercially available mesh network system (e.g., GOOGLE Wi-Fi). In some cases, other types of standard or conventional Wi-Fi transceiver devices may be used. The wireless communication devices 102A, 102B, 102C may be implemented without a Wi-Fi component; for example, other types of standard or non-standard wireless protocols for wireless communication may be used for motion detection.

[0021] exist Figure 1 In the example shown, a wireless communication device (e.g., 102A, 102B) (e.g., according to a wireless network standard, a motion detection protocol, a presence detection protocol, or other standard or non-standard protocol) sends a wireless signal on a wireless channel. For example, a wireless communication device may generate a motion detection signal for transmission to detect the motion or presence of a space to detect the motion of an object. In some implementations, the motion detection signal may include a standard signaling or communication frame, and the communication frame includes a standard pilot signal used in channel detection (e.g., channel detection for beamforming according to the IEEE802.11ac-2013 standard). In some cases, the motion detection signal includes a reference signal known to all devices in the network. In some instances, one or more wireless communication devices may process a motion detection signal, which is a signal received based on a motion detection signal sent through the space. For example, the motion detection signal may be analyzed to detect the motion of an object in the space, the absence of motion in the space, or the presence or absence of an object in the space when no motion is detected based on changes (or no changes) detected in the communication channel.

[0022] The wireless communication device (e.g., 102A, 102B) that sends the motion detection signal may be referred to as a source device. In some cases, the wireless communication devices 102A, 102B may broadcast a wireless motion detection signal (e.g., as described above). In other cases, the wireless communication devices 102A, 102B may send wireless signals addressed to other wireless communication devices 102C and other devices (e.g., user equipment, client devices, servers, etc.). The wireless communication device 102C and other devices (not shown) may receive the wireless signals sent by the wireless communication devices 102A, 102B. In some cases, the wireless signals sent by the wireless communication devices 102A, 102B may be repeated periodically, for example, according to a wireless communication standard or otherwise.

[0023] In some examples, wireless communication device 102C (which may be referred to as a sensor device) processes wireless signals received from wireless communication devices 102A, 102B to detect movement or lack of movement of objects in the space accessed by the wireless signals. In some examples, other devices or computing systems process wireless signals received by wireless communication device 102C from wireless communication devices 102A, 102B to detect movement or lack of movement of objects in the space accessed by the wireless signals. In some cases, wireless communication device 102C (or other systems or devices) processes wireless signals to detect the presence or absence of objects in the space where no motion is detected. In some instances, wireless communication device 102C (or other systems or devices) may perform the following regarding Figure 4 Or in about Figure 5 One or more operations described in the exemplary processes described, or other types of processing for detecting motion, detecting the absence of motion, or detecting the presence or absence of an object when no motion is detected. In other examples, for example, the wireless communication system 100 can be modified so that the wireless communication device 102C can transmit wireless signals, for example, as a source device, and the wireless communication devices 102A, 102B can process the wireless signals from the wireless communication device 102C, for example, as sensor devices, to detect motion, the absence of motion, or the presence when no motion is detected. That is, in some cases, the wireless communication devices 102A, 102B, 102C can each be configured as a source device, a sensor device, or both.

[0024] Wireless signals used for motion and / or presence detection may include, for example, beacon signals (e.g., Bluetooth beacons, Wi-Fi beacons, other wireless beacon signals), pilot signals (e.g., pilot signals used for channel detection according to the IEEE 802.11ac-2013 standard, such as pilot signals used in beamforming applications), or other standard signals generated for other purposes according to wireless network standards, or non-standard signals generated for motion and / or presence detection or other purposes (e.g., random signals, reference signals, etc.). In some cases, the wireless signals used for motion and / or presence detection are known to all devices in the network.

[0025] In some examples, the wireless signal may propagate through an object (e.g., a wall) before or after interacting with the mobile object, which may enable the detection of movement of the mobile object without an optical line of sight between the mobile object and the transmitting or receiving hardware. In some cases, the wireless signal may indicate the absence of motion in the space when received by the wireless communication device (e.g., 102C), for example, indicating that the object is not moving or no longer moving in the space. In some cases, the wireless signal may indicate the presence of an object in the space when no motion is detected when received by the wireless communication device (e.g., 102C). Conversely, the wireless signal may indicate the absence of an object in the space when no motion is detected. For example, based on the received wireless signal, the third wireless communication device 102C may generate motion data, presence data, or both. In some instances, the third wireless communication device 102C may communicate motion detection and / or presence data to other devices or systems (such as security systems, etc.), wherein the other devices or systems may include a control center for monitoring movement within a space such as a room, a building, an outdoor area, etc.

[0026] In some implementations, the wireless communication devices 102A, 102B may be configured to transmit the motion detection signal (e.g., as described above) on a wireless communication channel (e.g., a frequency channel or a coding channel) that is separate from the wireless network traffic signal. For example, the third wireless communication device 102C may know the modulation applied to the payload of the motion detection signal and the type or data structure of the data in the payload, which may reduce the amount of processing performed by the third wireless communication device 102C for motion and presence detection. The header may include, for example, additional information, such as an indication of whether other devices in the communication system 100 have detected motion or no motion, an indication of whether other devices in the communication system 100 have detected the presence of an object, an indication of the modulation type, identification of the device transmitting the signal, and the like.

[0027] exist Figure 1In the illustrated example, the wireless communication system 100 is shown as a wireless mesh network having wireless communication links between respective wireless communication devices 102. In the illustrated example, the wireless communication link between the third wireless communication device 102C and the first wireless communication device 102A can be used to detect the first motion detection zone 110A, the wireless communication link between the third wireless communication device 102C and the second wireless communication device 102B can be used to detect the second motion detection zone 110B, and the wireless communication link between the first wireless communication device 102A and the second wireless communication device 102B can be used to detect the third motion detection zone 110C. In some instances, each wireless communication device 102 may be configured to detect motion, lack of motion, and / or the presence or absence of an object in each motion detection zone 110 by processing a received signal based on a wireless signal sent by the wireless communication device 102 through the motion detection zone 110 accessed by the device. For example, when Figure 1 As the person 106 shown moves in the first motion detection zone 110A and the third motion detection zone 110C, the wireless communication device 102 may detect motion based on the signals it receives based on the wireless signals transmitted through the corresponding motion detection zones 110. For example, the first wireless communication device 102A may detect motion of the person in both the first motion detection zone 110A and the third motion detection zone 110C, the second wireless communication device 102B may detect motion of the person 106 in the motion detection zone 110C, and the third wireless communication device 102C may detect motion of the person 106 in the motion detection zone 110A. In some cases, in each of the motion detection zones 110A, 110B, 110C, it may be detected that the person does not move, and in other cases, the presence of the person may be detected without detecting movement of the person.

[0028] In some examples, motion detection zone 110 may include, for example, air, solid material, liquid, or other medium through which wireless electromagnetic signals may propagate. Figure 1In the example shown, the first motion detection zone 110A provides a wireless communication channel between the first wireless communication device 102A and the third wireless communication device 102C, the second motion detection zone 110B provides a wireless communication channel between the second wireless communication device 102B and the third wireless communication device 102C, and the third motion detection zone 110C provides a wireless communication channel between the first wireless communication device 102A and the second wireless communication device 102B. In some aspects of operation, wireless signals transmitted on a wireless communication channel (separate from or shared with a wireless communication channel used for network traffic) are used to detect movement or lack of movement of an object in a space, and can be used to detect the presence (or absence) of an object in a space where lack of movement is detected. The object can be any type of static or movable object, and can be animate or inanimate. For example, the object can be a person (e.g., Figure 1 The present invention also includes a person 106 shown in the figure), an animal, an inorganic object, or other device, equipment or assembly, an object used to define all or part of the boundaries of a space (e.g., a wall, door, window, etc.), or other types of objects. In some implementations, the motion information from the wireless communication device can trigger further analysis to determine the presence or absence of the object without detecting the movement of the object.

[0029] In some implementations, the wireless communication system 100 may be or may include a monitoring system. The monitoring system may include one or more wireless communication devices 102A, 102B, 102C and possibly other components. One or more wireless communication devices 102A, 102B, 102C in the monitoring system may be configured for motion detection, presence detection, or both (as described below). The monitoring system may include a database for storing signals. The stored signals may include corresponding measurements or metrics of each received signal (e.g., channel response information, beamforming state information, or other channel information), and the stored signals may be associated with channel states (e.g., motion, no motion, etc.). One of the wireless communication devices 102A, 102B, 102C of the monitoring system may include a central hub or server for processing received signals and other information to detect motion and / or presence. The wireless communication device 102 configured for motion detection may perform processing to detect motion in a space, and may make a request to a presence detector for further analysis of the space. The wireless communication device 102 configured for presence detection may perform processing to detect the presence (or absence) of an object in a space without detecting motion in the space. Storage of data (e.g., in a database) and / or determination of motion, lack of motion (e.g., a steady state), or presence detection may be performed on the wireless communication device 102 configured as a sensor device, a WAP device (e.g., a gateway device), or in some cases, may be performed on the cloud.

[0030] Figure 2A , 2B , 2C and 2D are diagrams showing exemplary wireless signals communicated between wireless communication devices 204A, 204B, 204C. Wireless communication devices 204A, 204B, 204C may be, for example, Figure 1 The wireless communication devices 102A, 102B, 102C shown may be other types of wireless communication devices. Examples of other types of wireless devices are wireless mesh devices, stationary wireless client devices, mobile wireless client devices, etc.

[0031] In some cases, the combination of one or more wireless communication devices 204A, 204B, 204C may form, or may be part of, a dedicated monitoring system. For example, as part of a dedicated monitoring system, one or more wireless communication devices 204A, 204B, 204C may be configured for motion detection, presence detection, or both in a monitoring system. In some cases, the combination of one or more wireless communication devices 204A, 204B, 204C may be, or may be part of, an ad hoc monitoring system.

[0032] Exemplary wireless communication devices 204A, 204B, 204C may transmit and / or receive wireless signals through the space 200. The exemplary space 200 may be completely or partially enclosed or open at one or more boundaries of the space 200. The space 200 may be or may include the interior of a room, a plurality of rooms, a building, an indoor area or an outdoor area, etc. In the example shown, the first wall 202A, the second wall 202B, and the third wall 202C at least partially enclose the space 200.

[0033] exist Figure 2A and 2BIn the example shown, the first wireless communication device 204A, for example, as a source device, is operable to repeatedly (e.g., periodically, intermittently, at predetermined, non-scheduled or random intervals, etc.) send a wireless motion detection signal. The second wireless communication device 204B and the third wireless communication device 204C, for example, as sensor devices, are operable to receive a signal based on the motion detection signal sent by the wireless communication device 204A. The motion detection signal can be formatted as described above. For example, in some implementations, the motion detection signal includes standard signaling or communication frames that include standard pilot signals used in channel detection (e.g., channel detection for beamforming according to the IEEE 802.11ac-2013 standard). The wireless communication devices 204B and 204C each have an interface, modem, processor, or other component configured to process the received motion detection signal to detect the motion or lack of motion of an object in the space 200. In some instances, wireless communication devices 204B, 204C may each have an interface, modem, processor, or other component configured to detect the presence or absence of an object in space 200 (e.g., whether the space is occupied or unoccupied) when no motion is detected.

[0034] As shown in the figure, the object is in Figure 2A The first position 214A at the initial time t=0 in FIG. 1 , and the object has moved to Figure 2B The second position 214B at the subsequent time t=1 in Figure 2A and 2B In the example, the moving object in space 200 is represented as a person, but the moving object can be other types of objects. For example, the moving object can be an animal, an inorganic object (e.g., a system, device, equipment, or assembly), an object used to define all or part of the boundaries of space 200 (e.g., a wall, door, window, etc.), or other types of objects. For this example, the representation of the movement of object 214 only indicates that the position of the object changes within space 200 between time t=0 and time t=1. In addition, Figures 2A to 2D The depiction of object 214 in is not intended to represent changes in position due to movement of object 214 in any particular direction or path that object 214 may have taken to change its position.

[0035] like Figure 2A and 2B2 , multiple exemplary paths of wireless signals transmitted from the first wireless communication device 204A are shown with dashed lines. Along the first signal path 216, the wireless signal is transmitted from the first wireless communication device 204A and is reflected by the first wall 202A toward the second wireless communication device 204B. Along the second signal path 218, the wireless signal is transmitted from the first wireless communication device 204A and is reflected by the second wall 202B and the first wall 202A toward the third wireless communication device 204C. Along the third signal path 220, the wireless signal is transmitted from the first wireless communication device 204A and is reflected by the second wall 202B toward the third wireless communication device 204C. Along the fourth signal path 222, the wireless signal is transmitted from the first wireless communication device 204A and is reflected by the third wall 202C toward the second wireless communication device 204B.

[0036] exist Figure 2A In FIG. 2 , along the fifth signal path 224A, a wireless signal is transmitted from the first wireless communication device 204A and is reflected by an object at the first location 214A toward the third wireless communication device 204C. Figure 2A The time t = 0 and Figure 2B During the time t=1 in FIG. 2 , the surface of the object moves from a first position 214A in the space 200 to a second position 214B (eg, a certain distance away from the first position 214A). Figure 2B In FIG. 2 , along the sixth signal path 224B, the wireless signal is transmitted from the first wireless communication device 204A and is reflected by the object at the second position 214B toward the third wireless communication device 204C. As the object moves from the first position 214A to the second position 214B, Figure 2B The sixth signal path 224B depicted in FIG. Figure 2A The fifth signal path 224A depicted in FIG is longer. In some examples, signal paths may be added, removed, or otherwise modified due to movement of objects in space.

[0037] Figure 2A and 2B The exemplary wireless signals shown may experience attenuation, frequency shift, phase shift or other effects through their respective paths, and may have portions that propagate in other directions, such as through walls 202A, 202B, and 202C. In some examples, the wireless signals are radio frequency (RF) signals. The wireless signals may include other types of signals.

[0038] exist Figure 2A and 2B In the example shown, the first wireless communication device 204A may be configured as a source device and may repeatedly send wireless signals. Figure 2AFIG. 2 shows that a wireless signal is transmitted from the first wireless communication device 204A during the first time t=0. The transmitted signal may be transmitted continuously, periodically, at random moments or intermittent moments, etc., or by a combination thereof. For example, the transmitted signal may be transmitted at times t=0 and t=0. Figure 2B The wireless signal may be transmitted one or more times between the subsequent time t=1 shown or any other subsequent time. The transmitted signal may have multiple frequency components in the frequency bandwidth. The transmitted signal may be transmitted from the first wireless communication device 204A in an omnidirectional manner, in a directional manner, or in other ways. In the example shown, the wireless signal passes through multiple corresponding paths in the space 200, and the signal along each path may become attenuated due to path loss, scattering or reflection, etc., and may have a phase offset or a frequency offset.

[0039] like Figure 2A and 2B As shown, signals from various paths 216, 218, 220, 222, 224A and 224B are combined at the third wireless communication device 204C and the second wireless communication device 204B to form a received signal. Due to the influence of multiple paths in the space 200 on the transmitted signal, the space 200 can be represented as a transfer function (e.g., a filter) that inputs the transmitted signal and outputs the received signal. When an object moves in the space 200, the attenuation or phase shift that affects the signal in the signal path may change, so the transfer function of the space 200 may change. Assuming that the same wireless signal is transmitted from the first wireless communication device 204A, if the transfer function of the space 200 changes, the output of the transfer function (e.g., the received signal) will also change. The change in the received signal can be used to detect the movement of the object. On the contrary, in some cases, if the transfer function of the space does not change, the output of the transfer function (received signal) will not change. The fact that the received signal does not change (e.g., a stable state) can indicate that there is no movement in the space 200. In some cases, when the received signal indicates no movement, the presence of an object may be detected by further analysis, for example, if object 214 is present in space 200 but no motion of the object is detected.

[0040] Mathematically, the transmission signal f(t) transmitted from the first wireless communication device 204A can be described according to equation (1):

[0041]

[0042] Among them, ω n represents the frequency of the nth frequency component of the transmitted signal, c nrepresents the complex coefficient of the nth frequency component, and t represents time. When the transmission signal f(t) is transmitted from the first wireless communication device 204A, the output signal r from the path k can be described according to equation (2): k (t):

[0043]

[0044] Among them, α n,k represents the attenuation factor (or channel response; e.g., due to scattering, reflection, and path loss) for the nth frequency component along path k, and φ n,k represents the phase of the signal for the nth frequency component along path k. Then, the received signal R at the wireless communication device can be described as all the output signals r from all the paths to the wireless communication device k The sum of (t), as shown in formula (3):

[0045]

[0046] Substituting equation (2) into equation (3) yields the following equation (4):

[0047]

[0048] Then, the received signal R at the wireless communication device can be analyzed. The received signal R at the wireless communication device can be transformed into the frequency domain using, for example, a Fast Fourier Transform (FFT) or other type of algorithm. The transformed signal can represent the received signal R as a series of n complex values, where (n frequency ω n The corresponding frequency components of each correspond to a complex value. n The frequency components of the complex value Y n It can be expressed as the following formula (5):

[0049]

[0050] For a given frequency component ω n The complex value of Y n Indicates the frequency component ω n The relative magnitude and phase shift of the received signal at the location. When the object moves in space, the complex value Y n Since the spatial channel response α n,k Therefore, the channel response (and hence the complex value Y n ) can indicate the movement of an object within the communication channel. n) indicates no movement. Thus, in some implementations, the complex value Y for each of the plurality of devices in the wireless mesh network may be analyzed. n To detect whether there is motion or no motion in the space through which the transmitted signal f(t) passes. In some cases, when no motion is detected, the channel response can be further analyzed to determine whether an object exists in the space but is not moving.

[0051] exist Figure 2A and 2B In another aspect of the invention, beamforming can be performed between devices based on some knowledge of the communication channel (e.g., feedback attributes generated by a receiver), where the knowledge can be used to generate one or more steering attributes (e.g., a steering matrix) that are applied by the transmitter device to shape the transmit beam / signal in a particular direction. Thus, as described herein, changes in the steering or feedback attributes used in the beamforming process indicate changes in the space accessed by the wireless communication system that may be caused by a moving object. For example, motion can be detected by significant changes in the communication channel over a period of time (e.g., as indicated by the channel response, or steering or feedback attributes, or any combination thereof).

[0052] For example, in some implementations, a steering matrix can be generated at a transmitter device (beamforming transmitting end) based on a feedback matrix provided by a receiver device (beamforming receiving end) based on channel detection. Since the steering matrix and the feedback matrix are related to the propagation characteristics of the channel, these matrices change as the object moves within the channel. The changes in channel characteristics are reflected accordingly in these matrices, and by analyzing these matrices, motion can be detected and different characteristics of the detected motion can be determined. In some implementations, a spatial mapping can be generated based on one or more beamforming matrices. The spatial mapping can indicate the general direction of an object in space relative to a wireless communication device. In some cases, a "mode" of a beamforming matrix (e.g., a feedback matrix or a steering matrix) can be used to generate a spatial mapping. Spatial mapping can be used to detect the presence of motion in space or to detect the location of a detected motion.

[0053] Figure 2C and 2D 2 is a diagram showing the space 200 at subsequent times t=2 and t=3 ... n (where n represents a further subsequent time). Figure 2C, the movement of object 214C may be detected by the monitoring system based on the detected changes in the channel information (e.g., the channel response) caused by object 214C. For example, analysis of the channel information of the wireless signal transmitted from wireless device 204A on signal path 224C at time t=2 may indicate that object 214C has moved from a previous time period (e.g., Figure 2B In the case of time t = 1, or in some cases, Figure 2A In some cases, the movement (or lack of movement) of object 214C can be detected by changes (or lack of changes) in other types of channel information (e.g., the state of the spatial beamforming transmitter). Figure 2D , object 214D exists in the space at time t=3, and in some cases, still exists after time t=3, but is not detected as moving. For example, object 214 is in the same position at time t=3 as it was at time t=2, and the received signals at 204B and 204C do not change during the same time period. In this example, analysis of channel information based on the wireless signal sent on signal path 224D at a subsequent time t=3 indicates that object 214D has not moved since the previous time t=2. This lack of movement can be detected based on identifying a stable state of the channel information. In this example, although object 214D does not move in space 200, it exists in the space (or occupies the space). In some instances, the channel information can be further analyzed to determine whether the object exists in the space (or occupies the space).

[0054] A wireless communication system configured as or including a monitoring system may be configured to cover a specific area (e.g., a coverage area) within a space. In some cases, one or more wireless communication devices configured for motion detection (e.g., a motion detector) and presence detection (e.g., a presence detector) may be deployed in different areas within a space. A wireless communication device configured for motion detection and / or presence detection may include instructions (e.g., in software or firmware) for performing motion detection and / or presence detection processing according to the embodiments described herein. For example, a wireless communication device 102 configured for presence detection may receive a wireless signal, for example, calculate a channel response (or other channel information) based on a wireless signal sent through its coverage area, and associate certain channel states with measurements. In an example, channel information or other metrics obtained during presence detection may be associated with a channel state indicating that there is no moving or stationary object in the coverage area. The association between the channel metric and the corresponding channel state may be established in various ways. In one instance, user-assisted and / or supervised machine learning may be used to establish an association. For example, a user can remotely provide information indicating that the coverage area is unoccupied to the presence detector via a mobile or web application interface (API), thereby effectively marking the measurements in the coverage area and establishing an association between the measurements and a specific channel state (e.g., unoccupied). In another instance, unsupervised machine learning can be used to establish the association. For example, the presence detection can continuously monitor measurements associated with a stable state (e.g., a stable channel response or a stable spatial beamforming transmitter state) and make statistical assumptions about when its coverage area is occupied or unoccupied. For example, if no changes in channel information are detected for a considerable period of time (e.g., a certain number of minutes or hours) during typical business hours, the presence detector can determine that its coverage area is unoccupied. In some instances, the presence detector establishes an association based on a combination of any or all of the above methods.

[0055] In some cases, the unoccupied environment may change over longer time intervals (e.g., hours, days, weeks, etc.). For example, in a typical residence, a resident may close or open a door or window, move furniture, or make other adjustments to the space sufficient to change the channel information in the coverage area. In one instance, the presence detector may remeasure the steady state within a defined time window and conclude that there is a new metric (e.g., new steady state channel information) indicating that the coverage area is "unoccupied." In this case, the presence detector may establish a new association between the new metric indicating "unoccupied" and the channel state. In some cases, the presence detector may maintain a database of all previously detected channel states corresponding to the "unoccupied" state and their associated metrics, and may add new metrics and their associated channel states to the database.

[0056] In some cases, the presence detector may receive a steady state indication and related metrics from a motion detector. In some cases, the presence detector establishes a reliable metric of unoccupied space. In other cases, the presence detection process may use a previously recorded metric as a metric of unoccupied space. In an example, the presence detector may compare its selected metric indicating unoccupied space with a new steady state metric received from the motion detector. In some cases, the presence detector may determine whether the object is still within the measurement zone based on the comparison.

[0057] Figure 3A and Figure 3B Examples of unoccupied spaces and occupied spaces where no movement is detected are shown. In some cases, the space 300 may be determined to be unoccupied or occupied based on the monitoring system's analysis of the signal. In some cases, one or more Wi-Fi presence detectors may measure received wireless signals and analyze related channel information. Based on this analysis, the monitoring system may determine that Figure 3A There is no object in the space shown, or it is judged as Figure 3B There are one or more objects in the space shown. In some examples, Figure 3A-3B The space 300 shown may be, for example, Figures 2A to 2D Space 200 is shown.

[0058] exist Figure 3A In the example shown, the space is shown as an empty space. In this case, the wireless communication device 304A sends one or more wireless signals through the space 300 on signal paths 310A, 312A and 314. In this case, the wireless signals received on paths 310A, 312A and 314 can have a channel shape 330A indicating that the space is not occupied when analyzed by the wireless communication device 304B in the time domain and / or frequency domain. During training or at other times, channel information or other types of signals corresponding to the channel shape 330A and their related "unoccupied" states can be stored in the database 340. For example, the database 340 can store data as a data vector. In some cases, the database 340 can be implemented with various complexities. For example, in some cases, the database 340 can be implemented as a simple programmable lookup table on a sensor device (e.g., the wireless communication device 304B), or in other cases, the database 340 can be a more complex database arrangement, and in some instances, for example, a full database engine can be included.

[0059] For example, in a typical human motion sequence, a human subject (e.g., object 306) may enter a coverage area (e.g., space 300), thereby causing constant changes to the channel information while moving through the coverage area. At some point in time, the subject may stop while being within the coverage area, resulting in stabilization of the channel information (e.g., the channel information is in a steady state). In this example, the motion detector may conclude that no motion is occurring within the coverage area, e.g., there is no motion. In some instances, the motion detector may provide a new steady state associated with no motion and its associated metrics to the presence detector to further investigate the subject within the coverage area.

[0060] exist Figure 3B In the example shown, the monitoring system can determine that the space 300 is occupied. For example, the object 306 depicted as a human subject exists in the space, but is not moving (e.g., the object is stationary). In some cases, the human subject may move insufficiently to be detected by the motion detector. For example, the change in channel information caused by the slight movement of the object 306 may not be enough for the motion detector to detect the movement of the object, and further, the motion detector may not be able to detect whether the object 306 still exists in the space. In some cases, the presence of the object 306 in the coverage area 300 may cause other minor changes to the environment through breathing activities such as exhalation or small body movements such as light swings. In some cases, the presence detector can analyze these types of changes in channel information (which may not otherwise trigger the detection of the movement of the measurement object) to determine the presence of the object 306 in the space without detecting the movement of the object. In some cases, these changes in channel information can be detected by the presence detector. In some cases, changes in the channel can be detected within a defined margin. In some cases, the presence detector can detect channel changes within a defined margin and determine the presence of the object in the measurement space when the channel changes do not otherwise indicate movement.

[0061] exist Figure 3B In FIG. 3 , wireless communication device 304A transmits one or more wireless signals through space 300 on signal paths 310B, 312B, and 316. In this case, the wireless signals received on paths 310B, 312B, and 316, when analyzed by wireless communication device 304B in the time domain and / or frequency domain, may have a channel shape 330B indicating that the space is occupied, which is different from a channel shape 330A of an unoccupied space. In some cases, during training of the monitoring system, channel information or other types of signals corresponding to channel shape 330B and their associated “occupied” status may be stored in database 340.

[0062] In some cases, when a change in channel information is detected within a defined margin that indicates the presence of a subject, but no motion of the subject, the presence detector may mark or flag the channel information accordingly. For example, the channel information may be marked to indicate "no motion, but presence detection is positive". In some cases, repeated or cyclic deviations from a steady state increase the confidence that the measured object is within the measurement zone.

[0063] In some cases, the presence detector may report its findings to a monitoring system (e.g., a motion detector) and, in some instances, to a user application interface of a user device. In some cases, it is reported that the measured object is not moving, but is still present within the measurement zone. In some cases, the motion detection system may store the findings of the presence detection analysis. In some instances, these findings may be used for further advanced analysis aggregation.

[0064] Figure 4 is shown based on, for example, the above Figures 2A to 2D Block diagram 400 of an example of a channel state of wireless signals communicated between wireless communication devices. The channel state may be used or determined by a monitoring system configured for motion detection and / or presence detection (e.g., one or more wireless communication devices 102 configured as motion detectors and / or presence detectors) to indicate a condition of a measured space for motion or occupancy of the space. In some cases, the channel information may be determined to be in a stable state, for example, as described above with respect to Figure 3A-3B As described, indicating an "unoccupied" 402 state or an "occupied (no motion)" 406 state. In some cases, the channel information may be determined to change over time. The change in the channel information may be caused by movement, such as indicating a "motion detected" 404 state. When in a particular channel state, one or more events that affect the channel information may cause the channel state to transition to another channel state.

[0065] In one example, the channel information indicates that the space is not occupied, such as in the "not occupied" 402 state. Such channel information can be considered a stable state because the channel information (e.g., the channel response or the state of the spatial beam transmitter) is not changing enough to indicate motion or in some cases presence. Figure 3A404 state.

[0066] In some cases, when the channel state is in the "occupied (no motion)" 406 state, further analysis may be performed to determine whether an object is still present in the space even if no motion is detected. For example, a presence detector of the monitoring system may analyze the channel information over time to detect any changes in the channel information that indicate the presence of an object. In some instances, these changes are not sufficient to trigger motion detection. For example, the changes detected by the presence detection aspect may not be sufficient to change the channel state of the space to "motion detected" 404. In one case, the detected changes may be within a defined margin, which indicates presence but no motion. The margin may be predefined by the monitoring system. In one case, the changes that can be detected by the presence detection aspect may be caused by minor changes in the environment (e.g., breathing activity such as exhalation or small body movements such as the swaying of an arm or leg, etc.). The monitoring system may detect these types of channel changes, which are smaller than channel changes that indicate motion and occur more slowly over time than channel changes that indicate motion, and are therefore insufficient to trigger motion detection. In some instances, the monitoring system may consider small changes in channel information to determine presence, particularly where the channel information changes within a defined margin and the channel state is still classified as an "occupied (no motion)" 406 state. In some cases, whenever these types of changes in channel information are detected by the presence detection aspect of the monitoring system, the channel state will indicate an "occupied (no motion)" 406 state. Additionally, measuring and detecting such small cyclic deviations from a known stable state provides increased confidence that an object is present in the space. In some cases, the channel shape (or other channel information) newly identified as corresponding to "occupied (no motion)" 406 is added to, for example, Figure 3B 408. In an example, if the monitoring system does not detect a channel change indicating presence within a certain predefined amount of time, the monitoring system may determine that the space is not occupied 430. In another case, the monitoring system may determine that the space is not occupied based on user feedback indicating that the measured space is not occupied 430. In either of these cases, the monitoring system may determine that a false detection of presence in the space has occurred 408, and determine that the space is not occupied. In this instance, the channel state may change to the "not occupied" 402 state.

[0067] The monitoring system may report its findings regarding the presence or occupancy of the space to another system or process, possibly in the cloud, for storage or further advanced analytical aggregation. These findings may also be reported to a user application interface of a user device. In some cases, these findings may indicate that an object is not moving, but is still present within a space (e.g., a coverage area).

[0068] Figure 5 is a flow chart illustrating an exemplary process 500 for detecting the presence of an object in a space based on channel information. The exemplary process 500 may be performed in a monitoring system (e.g., wireless communication system 100 or other types of wireless systems configured for motion detection and / or presence detection). In some implementations, Figure 5 The processing shown can be done by Figure 1 The exemplary process 500 may include additional or different operations, and these operations may be performed in the order shown or in another order. In some cases, Figure 5 One or more operations in the operations shown are implemented as a process including multiple operations, sub-processes for other types of routines. In some cases, the operations may be combined, performed in other orders, performed in parallel, iterated or otherwise repeated or performed in other ways.

[0069] At 510, motion of an object in a space is detected by analyzing a first signal set for motion in the space. In some cases, such as, for example Figure 2A and Figure 2B As shown, the first signal set is based on wireless signals transmitted by the wireless communication device through the space in the first time period. At 520, the absence of motion in the space is detected by analyzing the second signal set for motion in the space. In some cases, such as for example Figure 2C and Figure 2D As shown, the second signal set is based on wireless signals transmitted through space by the wireless communication device in a subsequent second time period.

[0070] At 530, the presence of an object in the space during the second time period is detected by analyzing the second signal set for presence in the space. In some cases, analyzing the second signal set for presence includes accessing a database of stored signals. In one example, the second signal set can be compared to the stored signals. In some examples, the database associates each stored signal with an occupied state of the space or an unoccupied state of the space. The stored signals can be or they can be based on, for example, channel shape (e.g., Figure 3A , 3B The exemplary channel shapes 330A, 330B shown) or other types of measurements or metrics of the channels.

[0071] In some cases, the process 500 may detect that an object is present in the space during the second time period. For example, in one case, when the second signal set matches a first subset of stored signals associated with an unoccupied state of the space, it is determined that an object is present. In another case, the process 500 may detect that an object is not present in the space during the second time period. For example, when the second signal set does not match a first subset of stored signals associated with an unoccupied state of the space, it is determined that an object is not present. In another case, when the presence of an object is detected, the second signal set may match a second subset of stored signals associated with an occupied state of the space.

[0072] In some cases, the second signal set is analyzed for changes over time. In some instances, these changes have characteristics associated with presence in space. For example, the characteristic may be a change in the channel, which may be depicted as Figure 2A and 2B The channel shape in the time domain or frequency domain illustrated, or the characteristic can be a user tag indicating that the space is occupied or unoccupied. In some cases, the process 500 can determine that the space is unoccupied during the second time period based on the absence of motion for a duration longer than a threshold duration. In some instances, the database can be updated to include new stored signals associated with the unoccupied state of the space based on the second signal set. In some cases, the stored signals can be obtained during a supervised motion detection training time period of the space. In other cases, these signals are obtained during an unsupervised training time period of the space.

[0073] Figure 6 is a block diagram illustrating an exemplary wireless communication device 600. Figure 6 As shown, the exemplary wireless communication device 600 includes a transmission and reception interface 630, a processor 610, a memory 620, and a power supply unit 640. For example, Figure 1Any of the wireless communication devices 102A, 102B, 102C in the wireless communication system 100 shown may include the same, additional, or different components, and the components may be configured as follows: Figure 1 In some implementations, the interface 630, processor 610, memory 620, and power supply unit 640 of the wireless communication device are housed together in a common housing or other assembly. In some implementations, one or more components of the wireless communication device may be housed separately, for example, in separate housings or other assemblies.

[0074] Exemplary interface 630 can communicate (receive, send or both) wireless signals. For example, interface 630 can be configured to communicate radio frequency (RF) signals formatted according to wireless communication standards (e.g., Wi-Fi or Bluetooth). Interface 630 can be implemented as the exemplary wireless interface 630 shown, or can be implemented in other ways (e.g., using other types of components or subsystems). In some cases, exemplary interface 630 can be implemented as a modem. In some implementations, exemplary interface 630 includes a radio subsystem and a baseband subsystem. In some cases, the baseband subsystem and the radio subsystem can be implemented on a common chip or chipset, or they can be implemented in a card or other type of assembly device. The baseband subsystem can be coupled to the radio subsystem, for example, by leads, pins, wiring or other types of connections.

[0075] In some cases, the radio subsystem in the interface 630 may include one or more antennas and a radio frequency circuit. The radio frequency circuit may, for example, include a circuit for filtering, amplifying or otherwise adjusting an analog signal, a circuit for up-converting a baseband signal to an RF signal, a circuit for down-converting an RF signal to a baseband signal, etc. Such circuits may, for example, include filters, amplifiers, mixers, local oscillators, etc. The radio subsystem may be configured to communicate radio frequency wireless signals on a wireless communication channel. As an example, the radio subsystem may include a radio chip, an RF front end, and one or more antennas. The radio subsystem may include additional or different components. In some implementations, the radio subsystem may be or include a radio electronic device (e.g., an RF front end, a radio chip, or similar components) from a traditional modem (e.g., from a Wi-Fi modem, a micro base station modem, etc.). In some implementations, the antenna includes multiple antennas.

[0076] In some cases, the baseband subsystem in interface 630 may, for example, include a digital electronic device configured to process digital baseband data. As an example, the baseband subsystem may include a baseband chip. The baseband subsystem may include additional or different components. In some cases, the baseband subsystem may include a digital signal processor (DSP) device or other types of processor devices. In some cases, the baseband system includes digital processing logic to operate a radio subsystem, communicate wireless network services through the radio subsystem, detect motion based on motion detection signals received by the radio subsystem, or perform other types of processing. For example, the baseband subsystem may include one or more chips, chipsets, or other types of devices, wherein these devices are configured to encode signals and transmit the encoded signals to the radio subsystem for transmission, or (for example, by decoding the signal according to a wireless communication standard, by processing the signal according to motion detection processing, or otherwise) identify and analyze the data encoded in the signal from the radio subsystem.

[0077] In some instances, the radio subsystem in the exemplary interface 630 receives a baseband signal from the baseband subsystem, up-converts the baseband signal to a radio frequency (RF) signal, and wirelessly transmits the RF signal (e.g., via an antenna). In some instances, the radio subsystem in the exemplary interface 630 wirelessly receives the RF signal (e.g., via an antenna), down-converts the RF signal to a baseband signal, and transmits the baseband signal to the baseband subsystem. The signals exchanged between the radio subsystem and the baseband subsystem may be digital signals or analog signals. In some examples, the baseband subsystem includes a conversion circuit (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges analog signals with the radio subsystem. In some examples, the radio subsystem includes a conversion circuit (e.g., a digital-to-analog converter, an analog-to-digital converter) and exchanges digital signals with the baseband subsystem.

[0078] In some cases, the baseband subsystem of the exemplary interface 630 can communicate wireless network services (e.g., data packets) in a wireless communication network through a radio subsystem on one or more network traffic channels. The baseband subsystem of the modem 112 can also send or receive (or both) signals (e.g., motion detection signals) through a radio subsystem on a dedicated wireless communication channel. In some instances, the baseband subsystem, for example, generates a motion detection signal for transmission to detect motion or no motion in the space. In some implementations, the motion detection signal includes a standard signaling or communication frame, and the communication frame includes a standard pilot signal used in channel detection (e.g., channel detection for beamforming according to the IEEE 802.11ac-2013 standard). In some cases, the motion detection signal includes a reference signal known to all devices in the network. In some instances, the baseband subsystem can, for example, process the received signal to detect the motion of an object in the space, the absence of motion in the space, or the presence or absence of an object in the space when no motion is detected. For example, the baseband subsystem may analyze aspects of standard signaling protocols (e.g., channel sounding for beamforming in accordance with the IEEE 802.11ac-2013 standard, such as based on generated steering or other matrices, etc.) to detect channel changes as a result of motion in space.

[0079] The exemplary processor 610 may, for example, execute instructions to generate output data based on data input. The instructions may include programs, codes, scripts, modules, or other types of data stored in the memory 620 (e.g., database 340). Additionally or alternatively, the instructions may be encoded as pre-programmed or reprogrammable logic circuits, logic gates, or other types of hardware or firmware components or modules. The processor 610 may be or include a general-purpose microprocessor as a dedicated coprocessor or other type of data processing device. In some cases, the processor 610 performs high-level operations of the wireless communication device 600. For example, the processor 610 may be configured to execute or interpret software, scripts, programs, functions, executable instructions, or other instructions stored in the memory 620. In some implementations, the processor 610 is included in the interface 630.

[0080] Exemplary memory 620 may include computer-readable storage media, such as volatile memory devices, non-volatile memory devices, or both. Memory 620 may include one or more read-only memory devices, random access memory devices, buffer memory devices, or a combination of these and other types of memory devices. In some instances, one or more components of the memory may be integrated or otherwise associated with other components of wireless communication device 600. Memory 620 may store instructions executable by processor 610. For example, the instructions may include instructions for, for example, Figure 4One or more of the operations depicted or in Figure 5 Instructions for analyzing channel information to detect motion of an object in space, detect the absence of motion in space, and detect the presence or absence of an object without detecting motion are shown in the exemplary process 500. In some examples, the memory 620 may include motion detection instructions 622 for detecting motion and the absence of motion, and presence detection instructions 624 for detecting the presence or absence of an object without detecting motion.

[0081] An exemplary power supply unit 640 provides power to other components of the wireless communication device 600. For example, the other components may operate based on power provided by the power supply unit 640 through a voltage bus or other connection. In some implementations, the power supply unit 640 includes a battery or battery system, such as a rechargeable battery. In some implementations, the power supply unit 640 includes an adapter (e.g., an AC adapter) that receives an external power signal (from an external source) and converts the external power signal into an internal power signal that is conditioned for the components of the wireless communication device 600. The power supply unit 620 may include other components or operate in other ways.

[0082] Some of the themes and operations described in this specification may be implemented in digital electronic circuits, or in computer software, firmware or hardware, including the structures disclosed in this specification and their structural equivalents, or one or more combinations of the structures. Some of the themes described in this specification may be implemented as one or more computer programs (i.e., one or more modules of computer program instructions), encoded on a computer storage medium for execution by a data processing device or for controlling the operation of a data processing device. A computer storage medium may be a computer-readable storage device, a computer-readable storage substrate, a random or serial access memory array or device, or a combination of one or more of them, or may be included therein. In addition, although a computer storage medium is not a propagation signal, a computer storage medium may be a source or destination of computer program instructions encoded in an artificially generated propagation signal. A computer storage medium may also be one or more separate physical components or media (e.g., multiple CDs, disks or other storage devices), or be included therein.

[0083] Some of the operations described in this specification can be implemented as operations performed by a data processing apparatus on data stored on one or more computer-readable storage devices or received from other sources.

[0084] The term "data processing equipment" encompasses all kinds of equipment, devices and machines for processing data, including, for example, a programmable processor, a computer, a system on a chip, or a plurality or combination of the foregoing. The equipment may include special-purpose logic circuits, such as an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit). In addition to hardware, the equipment may also include code that creates an execution environment for the computer program under consideration, such as code for constituting processor firmware, a protocol stack, a database management system (e.g., database 340), an operating system, a cross-platform runtime environment, a virtual machine, or a combination of one or more of them.

[0085] A computer program (also known as a program, software, software application, script or code) can be written in any form of programming language including compiled or interpreted languages, declarative languages ​​or procedural languages, and can be deployed in any form, including being deployed as a standalone program or as a module, component, subroutine, object or other unit suitable for use in a computing environment. A computer program may but need not correspond to a file in a file system. A program may be stored in a portion of a file, where the file stores other programs or data (e.g., one or more scripts stored in a markup language file) in a single file dedicated to the program, or in multiple coordination files (e.g., a file for storing a portion of one or more modules, subroutines or codes). A computer program may be deployed to execute on one computer, or on multiple computers located at one site or distributed across multiple sites and interconnected by a communication network.

[0086] Some of the processes and logic flows described in this specification can be performed using one or more programmable processors that execute one or more computer programs to perform actions by operating on input data and generating output. These processes and logic flows can also be performed by and devices can be implemented as special purpose logic circuits, such as FPGAs (field programmable gate arrays) or ASICs (application-specific integrated circuits).

[0087] For example, processors suitable for executing computer programs include both general-purpose microprocessors and special-purpose microprocessors, and processors in any type of digital computer. Generally, the processor will receive instructions and data from a read-only memory or a random access memory or both. The elements of a computer may include a processor for performing actions according to instructions and one or more memory devices for storing instructions and data. The computer may also include one or more large-capacity storage devices (e.g., magnetic disks, magneto-optical disks, or optical disks) for storing data or may be operably coupled to receive or transmit data relative to the one or more large-capacity storage devices, or both. However, the computer does not need to have such a device. In addition, the computer may be embedded in other devices (e.g., telephones, electrical appliances, mobile audio or video players, game consoles, global positioning system (GPS) receivers, or portable storage devices (e.g., universal serial bus (USB) flash drives)). Devices suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and memory devices, including, for example, semiconductor memory devices (e.g., EPROM, EEPROM, and flash memory devices, etc.), magnetic disks (e.g., internal hard disks and removable disks, etc.), magneto-optical disks, and CD-ROM and DVD-ROM disks. In some cases, the processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

[0088] To provide interaction with a user, operations may be implemented on a computer having a display device (e.g., a monitor or other type of display device) for displaying information to the user, and a keyboard and pointing device (e.g., a mouse, trackball, tablet computer, touch-sensitive screen, or other type of pointing device) through which the user can provide input to the computer. Other types of devices may also be used to provide interaction with a user; for example, feedback provided to the user may be any form of sensory feedback, such as visual feedback, auditory feedback, or tactile feedback; and input from the user may be received in any form, including sound, voice, or tactile input. In addition, a computer may interact with a user by sending and receiving documents relative to a device used by the user (e.g., by sending a web page to a web browser in response to a request received from a web browser on a client device of the user).

[0089] A computer system may include a single computing device, or multiple computers operating close to or generally remote from each other and typically interacting through a communication network. Examples of communication networks include local area networks ("LAN") and wide area networks ("WAN"), Internet (e.g., the Internet), networks including satellite links, and peer-to-peer networks (e.g., ad hoc peer-to-peer networks). The relationship of client and server may arise through computer programs running on the respective computers and having a client-server relationship to each other.

[0090] In the general aspects described herein, a surveillance system detects the presence of an object in a space, for example, without detecting motion.

[0091] In a first example, a monitoring system detects movement of an object in a space by analyzing a first signal set for movement in the space. The first signal set is based on wireless signals sent through the space by a wireless communication device in a first time period. The absence of movement in the space is detected by analyzing a second signal set for movement in the space. The second signal set is based on wireless signals sent through the space by the wireless communication device in a subsequent second time period. Whether an object is in the space during a second time period is detected by analyzing the second signal set for presence in the space.

[0092] Implementations of the first example, the second example, and the third example may include one or more of the following features. A database of stored signals may be accessed. The database associates each stored signal with an occupied state of the space or an unoccupied state of the space. A second signal set is compared with the stored signals. The absence of an object in the space during the second time period is detected by analyzing the second signal set for presence in the space and determining that the second signal set matches one of the first subsets of stored signals; the first subsets of stored signals are each associated with the unoccupied state of the space. The presence of an object in the space during the second time period is detected by analyzing the second signal set for presence in the space and determining that the second signal set does not match any of the first subsets of stored signals; the first subsets of stored signals are each associated with the unoccupied state of the space. The second signal set may be analyzed for presence in the space by determining that the second signal set matches one of the second subsets of stored signals; the second subsets of stored signals are each associated with the occupied state of the space. The second signal set may be analyzed for presence in the space by analyzing the second signal set for changes over time; the changes have characteristics associated with presence in the space. The space may be determined to be unoccupied during the second time period based on feedback from the user device, and the database may be updated to include new stored signals based on the second signal set, wherein the new stored signals are associated with the unoccupied state of the space. The space may be determined to be unoccupied during the second time period based on the absence of motion for a duration longer than a threshold duration, and the database may be updated to include new stored signals based on the second signal set, wherein the new stored signals are associated with the unoccupied state of the space. The stored signals may be obtained during a supervised motion detection training period of the space or during an unsupervised training period of the space.

[0093] In a second example, a computer-readable storage medium stores instructions that, when executed by a data processing device, are operable to perform one or more operations of the first example.

[0094] In a third example, a monitoring system includes: one or more processors; and a memory including instructions that, when executed by the one or more processors, are operable to perform one or more operations of the first example.

[0095] Although this specification contains many details, these details should not be construed as limitations on the scope of what is claimed, but rather as descriptions of features specific to a particular example. Certain features described in this specification or shown in the drawings in the context of separate implementations may also be combined. Conversely, various features described or shown in the context of a single implementation may also be implemented separately or in any suitable subcombination in multiple embodiments.

[0096] Equally, although described operation in specific order in the accompanying drawings, this should not be understood as requiring to carry out these operations or carry out all shown operations to realize desired result in the specific order shown or in sequence order.In some cases, multi-tasking and parallel processing can be advantageous.In addition, the separation of various system components in the above-mentioned implementation should not be understood as requiring this separation in all implementations, and should be understood that described program components and system can be integrated together in a single product or be packaged in multiple products usually.

[0097] A number of embodiments have been described. However, it should be understood that various modifications can be made. Therefore, other embodiments are within the scope of the following claims.

Claims

1. A method for detecting presence, include: detecting motion of an object in the space by analyzing a first signal set for motion in the space, the first signal set being a signal set of wireless signals transmitted through the space over a wireless communication link in a wireless communication network between a first wireless communication device and a second wireless communication device in accordance with a wireless communication protocol during a first time period; detecting the absence of motion in the space by analyzing a second set of signals for motion in the space, the second set of signals being based on a set of signals of wireless signals transmitted through the space over a wireless communication link in the wireless communication network according to the wireless communication protocol between the first wireless communication device and the second wireless communication device during a subsequent second time period; as well as In the event that the object in the space is detected to be stationary or the object in the space is moving insufficiently to be detected, detecting whether an object is present in the space during the second time period by analyzing the second signal set for the presence of the object in the space.

2. The method according to claim 1, in, Analyzing the second set of signals for the presence of an object in the space includes: accessing a database of stored signals, wherein the database associates each stored signal with an occupied state of the space or an unoccupied state of the space; and The second signal set is compared to the stored signals.

3. The method according to claim 2, further comprising: include: detecting that no object is present in the space during the second time period, Wherein, analyzing the second set of signals for the presence of an object in the space includes determining that the second set of signals matches one of the first subsets of stored signals, each of the first subsets of stored signals being associated with an unoccupied state of the space.

4. The method according to claim 2, further comprising: include: detecting that an object is present in the space during the second time period, Wherein, analyzing the second signal set for the presence of objects in the space includes determining that the second signal set does not match any first subset of the stored signals, and the first subsets of the stored signals are each associated with an unoccupied state of the space.

5. The method according to claim 4, in, Analyzing the second set of signals for the presence of an object in the space further includes determining that the second set of signals matches one of a second subset of the stored signals, the second subset of stored signals each being associated with an occupied state of the space.

6. The method according to claim 4, in, Analyzing the second set of signals for presence of an object in the space further comprises analyzing the second set of signals for changes over time, wherein the changes have characteristics associated with the presence of an object in the space.

7. The method according to claim 2, further comprising: include: determining, based on feedback from a user device, that the space is not occupied during the second time period; as well as The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

8. The method according to claim 2, further comprising: include: determining that the space is unoccupied during the second time period based on a lack of movement for a duration longer than a threshold duration; as well as The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

9. The method according to claim 2, in, The stored signal includes one or more of the following: stored signals obtained during a supervised motion detection training period for the space; or The stored signals obtained during the unsupervised training period of the space.

10. The method according to claim 1, in, The first set of signals and the second set of signals are addressed from the first wireless communication device to the second wireless communication device according to the wireless communication protocol.

11. A computer-readable storage medium storing instructions which, when executed by a data processing device, can be executed to perform an operation, the operation include: detecting motion of an object in the space by analyzing a first signal set for motion in the space, the first signal set being a signal set of wireless signals transmitted through the space over a wireless communication link in a wireless communication network between a first wireless communication device and a second wireless communication device in accordance with a wireless communication protocol during a first time period; detecting the absence of motion in the space by analyzing a second set of signals for motion in the space, the second set of signals being based on a set of signals of wireless signals transmitted through the space over a wireless communication link in the wireless communication network according to the wireless communication protocol between the first wireless communication device and the second wireless communication device during a subsequent second time period; as well as In the event that the object in the space is detected to be stationary or the object in the space is moving insufficiently to be detected, detecting whether an object is present in the space during the second time period by analyzing the second signal set for the presence of the object in the space.

12. The computer-readable storage medium according to claim 11, in, Analyzing the second set of signals for the presence of an object in the space includes: accessing a database of stored signals, wherein the database associates each stored signal with an occupied state of the space or an unoccupied state of the space; and The second signal set is compared to the stored signals.

13. The computer-readable storage medium of claim 12, wherein the operation further comprises: include: detecting that no object is present in the space during the second time period, Wherein, analyzing the second set of signals for the presence of an object in the space includes determining that the second set of signals matches one of the first subsets of stored signals, each of the first subsets of stored signals being associated with an unoccupied state of the space.

14. The computer-readable storage medium of claim 12, wherein the operation further comprises: include: detecting that an object is present in the space during the second time period, Wherein, analyzing the second signal set for the presence of objects in the space includes determining that the second signal set does not match any first subset of the stored signals, and the first subsets of the stored signals are each associated with an unoccupied state of the space.

15. The computer-readable storage medium according to claim 14, in, Analyzing the second set of signals for the presence of an object in the space further includes determining that the second set of signals matches one of a second subset of the stored signals, the second subset of stored signals each being associated with an occupied state of the space.

16. The computer-readable storage medium according to claim 14, in, Analyzing the second set of signals for presence of an object in the space further comprises analyzing the second set of signals for changes over time, wherein the changes have characteristics associated with the presence of an object in the space.

17. The computer-readable storage medium of claim 12, wherein the operation further comprises: include: determining, based on feedback from a user device, that the space is not occupied during the second time period; as well as The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

18. The computer-readable storage medium of claim 12, wherein the operation further comprises: include: determining that the space is unoccupied during the second time period based on a lack of movement for a duration longer than a threshold duration; as well as The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

19. The computer-readable storage medium according to claim 12, in, The stored signal includes one or more of the following: stored signals obtained during a supervised motion detection training period for the space; or The stored signals obtained during the unsupervised training period of the space.

20. A monitoring system, include: a wireless communication device configured to transmit a wireless signal through space on a wireless communication link in a wireless communication network according to a wireless communication protocol, the wireless communication device comprising a first wireless communication device and a second wireless communication device; one or more processors; a memory storing instructions that, when executed by the one or more processors, cause the monitoring system to: detecting motion of an object in the space by analyzing a first signal set for motion in the space, the first signal set being a signal set of wireless signals transmitted through the space over a wireless communication link in the wireless communication network according to the wireless communication protocol between the first wireless communication device and the second wireless communication device during a first time period; detecting the absence of motion in the space by analyzing a second set of signals for motion in the space, the second set of signals being based on a set of signals of wireless signals transmitted through the space over a wireless communication link in the wireless communication network according to the wireless communication protocol between the first wireless communication device and the second wireless communication device during a subsequent second time period; as well as In the event that the object in the space is detected to be stationary or the object in the space is moving insufficiently to be detected, detecting whether an object is present in the space during the second time period by analyzing the second signal set for the presence of the object in the space.

21. The monitoring system according to claim 20, further comprising: include: A database comprising stored signals, wherein the database associates each stored signal with an occupied state of the space or an unoccupied state of the space, and analyzing the second set of signals for the presence of objects in the space comprises comparing the second set of signals with the stored signals.

22. The monitoring system according to claim 21, in, The instructions, when executed by the one or more processors, cause the monitoring system to detect that an object is not present in the space during the second time period if the second set of signals matches one of the first subsets of the stored signals, each of which is associated with an unoccupied state of the space.

23. The monitoring system according to claim 21, in, The instructions, when executed by the one or more processors, cause the monitoring system to detect the presence of an object in the space during the second time period if the second set of signals does not match any first subset of the stored signals, each of the first subsets of the stored signals being associated with an unoccupied state of the space.

24. The monitoring system according to claim 23, in, The instructions, when executed by the one or more processors, cause the monitoring system to detect the presence of an object in the space during the second time period if the second set of signals matches any second subset of the stored signals, each of which is associated with an occupied state of the space.

25. The monitoring system according to claim 21, in, The instructions, when executed by the one or more processors, cause the monitoring system to detect the presence of an object in the space during the second time period if analysis of the second set of signals indicates a change having a characteristic associated with the presence of the object in the space.

26. The monitoring system according to claim 21, in, The instructions, when executed by the one or more processors, cause the monitoring system to further: determining, based on feedback from a user device, that the space is not occupied during the second time period; and The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

27. The monitoring system according to claim 21, in, The instructions, when executed by the one or more processors, cause the monitoring system to further: determining that the space is unoccupied during the second time period based on a lack of movement for a duration longer than a threshold duration; and The database is updated to include new stored signals based on the second signal set, wherein the database associates the new stored signals with an unoccupied state of the space.

28. The monitoring system according to claim 21, in, The stored signal includes one or more of the following: stored signals obtained during a supervised motion detection training period for the space; or The stored signals obtained during the unsupervised training period of the space.

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