Changing transmit and / or receive characteristics to detect events other than human presence

Abstract

A system (1) is configured to: cause a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic, for example, by a lighting device (31-37); detect whether a change in the first set of radio frequency signals is caused by the presence of a human (49); detect whether the change in the first set of radio frequency signals has an additional cause; and upon detecting that the change in the first set of radio frequency signals has an additional cause, cause a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic. The system is further configured to identify the additional cause based on the change in the second set of radio frequency signals and to provide an output that includes or is dependent on the additional cause.

Description

Technical Field

[0001] The present invention relates to a system for detecting human presence based on changes in received radio frequency signals.

[0002] The invention further relates to a method for detecting human presence based on changes in received radio frequency signals.

[0003] The invention also relates to a computer program product enabling a computer system to perform such a method. Background Art

[0004] In smart homes and offices, presence detection is becoming increasingly important for, for example, automatically turning lights on and off and controlling heating and air conditioning. Over the past few years, network-based presence sensing technologies have matured and emerged on the market. A notable example is Ivani's "Network Presence Sensing" technology. Applications for this technology range from detecting motion based on environmental changes to counting and locating people.

[0005] The main idea behind this technology is to measure changes in metrics of wireless messages (e.g., between IoT devices). This is typically achieved using RF communication and is referred to as RF-based sensing. The location and number of people, their weight, direction of movement, and other parameters influence this behavior, allowing detection of a single person or group of people based on changes in signal strength or channel state information (CSI).

[0006] The accuracy and versatility of the system depend on the number of communicating devices and generally get better as more devices are present (the minimum number of devices is two, so that signals can be generated and received to evaluate their behavior). Tiffany M. Phan of the Air Force Institute of Technology describes several techniques for implementing RF-based sensing in her paper titled "RSS-based device-free passive detection and localization using home automation network radio frequencies" (March 2018). For example, baseline comparison is an intuitive method for RSS-based detection, where an object is detected in the area of ​​interest if the RSS decreases significantly from the baseline.

[0007] Currently, RF-based sensing is trained and tuned to detect human presence and discard other events. However, RF-based sensing can also be used to detect other events that cannot be classified as human presence (assuming these events generate detectable changes in wireless message indicators).

[0008] US 2019 / 250265 A1 discloses a system comprising a radio frequency (RF) wireless communication network (network), comprising a plurality of nodes in an area and a computer coupled to the network. Each node comprises a transmitter and a receiver. At a plurality of time instants, each transmitter transmits an RF spectrum signal (signal), and each receiver receives these signals and generates data indicative of signal characteristics of the received signals propagating through the network. When each of the plurality of time instants is a current time instant, the computer obtains the signal indicative data, determines a modification in the current time instant's indicative data from the previous time instant's indicative data (due to movement of occupants in the area), and detects occupancy conditions in the area based on the modifications in the indicative data and parameters configured in the network. Summary of the Invention

[0009] It is a first object of the present invention to provide a system that uses radio frequency based sensing to detect events other than human presence.

[0010] It is a second object of the present invention to provide a method that uses radio frequency based sensing to detect events other than human presence.

[0011] In a first aspect of the present invention, a system for detecting human presence based on changes in received radio frequency signals includes at least one input interface, at least one output interface, and at least one processor, the at least one processor being configured to: cause a first group of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic via the at least one output interface; detect via the at least one input interface whether the change in the first group of radio frequency signals is caused by human presence; detect via the at least one input interface whether the change in the first group of radio frequency signals has another cause; upon detecting that the change in the first group of radio frequency signals has another cause, cause a second group of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic via the at least one output interface, the second transmission characteristic being different from the first transmission characteristic, and the second reception characteristic being different from the first reception characteristic; identify the another cause based on the change in the second group of radio frequency signals; and provide an output including the another cause or depending on the another cause via the at least one output interface.

[0012] RF-based sensing detects changes in RF signals (primarily caused by water or metal). Therefore, it's generally suitable for human presence detection, but other large bodies of water (which absorb RF signals) and large metal objects (which reflect RF signals) can also affect it. Because RF-based sensing works by detecting changes in RF signals, there's a temporal component. For example, other causes of RF signal changes could include a slow increase in water, a sudden change in water, water moving between floors, or a moving or parked car.

[0013] Transmit and receive characteristics optimized for human presence detection are often not optimal for detecting other events. Therefore, it may be necessary to use different transmit and / or receive characteristics to accurately determine the additional cause of the change in the RF signal. The result is a multi-step RF-based sensing process. For example, the first set of one or more RF signals and the second set of one or more RF signals may differ in message rate, transmit frequency, duration, content, and / or transmitting device. For example, the first and second receive characteristics may differ in the number of antennas used to receive the RF signals and / or in the receiving device(s). An example of providing an output (dependent on the additional cause) is controlling a lighting device according to a light setting associated with the additional cause.

[0014] The first and second groups of RF signals may differ in a single transmit or receive characteristic, but they may also differ in multiple transmit characteristics and / or multiple receive characteristics. The difference between the first characteristic and the second characteristic may lie in the type of characteristic used or the value of a particular type of characteristic used. As an example of the former, signal amplitude variation may be used for the second group of RF signals but not for the first group of RF signals. As an example of the latter, the values ​​of the transmit frequencies used may differ.

[0015] The at least one processor may be configured to detect the human presence and / or identify the additional cause by comparing the change in the radio frequency signal to signatures of known causes. This allows events other than human presence to be classified if they have detectable signatures that can be used to infer the event.

[0016] The at least one processor may be configured to transmit a message including the additional reason via the at least one output interface. This enables alerting a user that an event has been detected, for example to allow the user to check whether the event is unusual. The message may also be transmitted to inform the user that an expected event has occurred, for example, "The bathtub is ready."

[0017] The at least one processor may be configured to control the lighting device via the at least one output interface in response to detecting human presence and / or in response to identifying the additional reason. For example, the light source of the lighting device may be automatically activated upon detecting human presence and automatically deactivated when no human presence is detected for a certain period of time. For example, when it rains, the intensity of the light source of the outdoor lighting device may be increased. Alternatively or additionally, the user may be informed of the additional reason with the help of the lighting device (e.g., by flashing a red light if there may be a water leak). The lighting device may be controlled by controlling a smart plug (e.g., a Hue smart plug) coupled to the lighting device. In this case, in response to detecting human presence and / or in response to identifying the additional reason, the lighting device (and thereby its light source) may be turned on or off via the smart plug. In response to detecting human presence and / or in response to identifying the additional reason, a sound may be presented instead of or in addition to presenting light.

[0018] The at least one processor may be configured to determine the change in the RF signal by comparing a signal strength of the RF signal with a signal strength of a previous RF signal received at a previous moment in time. By determining the change between consecutive signal strengths, it is not necessary to determine the signal strength of a reference RF signal at a reference moment in time (e.g., a moment in time when no human is present and no other events are occurring).

[0019] The at least one processor can be configured to determine the change in the RF signal by comparing the signal strength of the RF signal to the signal strength of a reference RF signal received at a reference time. While this requires calibration of the system, in some cases this may make it easier to match the change to a signature of a known cause. For example, the reference time may be a time when no humans are present and no other events are occurring, and the calibration can also be completed automatically without user intervention.

[0020] The at least one processor may be configured to further identify the additional cause based on whether the human presence is detected. The presence of a human may make it easier to identify the additional cause. For example, by detecting the presence of a human, it may be possible to distinguish a person showering from a leak.

[0021] The at least one processor may be configured to identify the further cause further based on data obtained from one or more further sensors.For example, a presence sensor may be used to differentiate whether a detected large body of water is caused by multiple people or by a leak.

[0022] The at least one processor can be configured to detect additional human presence based on the second set of RF signals. Although the transmission characteristics and / or reception characteristics of the second set of RF signals are optimized to identify additional causes, it is also possible to detect human presence based on these signals (e.g., in certain circumstances).

[0023] The at least one processor may be configured to receive user feedback via the at least one input interface and use the user feedback to improve the software for identifying the additional reason. The user feedback may include the user changing the setting immediately after providing the output. The user may be asked to clarify why he changed the setting. The user feedback may be transmitted to an internet server.

[0024] In a second aspect of the present invention, a method for detecting human presence based on changes in received radio frequency signals comprises: causing a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic; detecting whether the change in the first set of radio frequency signals is caused by human presence; detecting whether the change in the first set of radio frequency signals has another cause; upon detecting that the change in the first set of radio frequency signals has another cause, causing a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic, the second transmission characteristic being different from the first transmission characteristic and the second reception characteristic being different from the first reception characteristic; identifying the another cause based on the change in the second set of radio frequency signals; and providing an output including or dependent on the another cause. The method may be performed by software running on a programmable device. The software may be provided as a computer program product.

[0025] Furthermore, a computer program for executing the method described herein and a non-transitory computer-readable storage medium storing the computer program are provided. For example, the computer program can be downloaded from or uploaded to an existing device, or stored when these systems are manufactured.

[0026] A non-transitory computer-readable storage medium stores at least one software code portion that, when executed or processed by a computer, is configured to perform executable operations to detect human presence based on changes in received radio frequency signals.

[0027] The executable operations include: causing a first group of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic; detecting whether a change in the first group of radio frequency signals is caused by human presence; detecting whether the change in the first group of radio frequency signals has another cause; upon detecting that the change in the first group of radio frequency signals has another cause, causing a second group of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic, the second transmission characteristic being different from the first transmission characteristic, and the second reception characteristic being different from the first reception characteristic; identifying the another cause based on the change in the second group of radio frequency signals; and providing an output including the another cause or depending on the another cause.

[0028] As will be appreciated by those skilled in the art, aspects of the present invention may be embodied as devices, methods, or computer program products. Thus, aspects of the present invention may take the form of entirely hardware embodiments, entirely software embodiments (including firmware, resident software, microcode, etc.), or embodiments combining software and hardware aspects (which aspects are generally referred to herein as "circuits," "modules," or "systems"). The functions described in this disclosure may be implemented as algorithms executed by a processor / microprocessor of a computer. Furthermore, aspects of the present invention may take the form of a computer program product embodied in one or more computer-readable media having computer-readable program code embodied (e.g., stored) therein.

[0029] Any combination of one or more computer-readable media may be utilized. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of computer-readable storage media may include, but are not limited to, an electrical connection having one or more conductors, a portable computer disk, a hard disk, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of the present invention, a computer-readable storage medium may be any tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device.

[0030] A computer-readable signal medium may include a propagated data signal having computer-readable program code embodied therein (e.g., in baseband or as part of a carrier wave). Such a propagated signal may take any of a variety of forms, including, but not limited to, electromagnetic, optical, or any suitable combination thereof. A computer-readable signal medium may be any computer-readable medium that is not a computer-readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device.

[0031] Any suitable medium can be used to transmit (being embodied in computer-readable medium) program code, and this medium includes but is not limited to wireless, wired, optical fiber, cable, RF etc., or any suitable combination of the foregoing.The computer program code for carrying out the operation of aspects of the present invention can be written with any combination of one or more programming languages, and these one or more programming languages ​​comprise object-oriented programming languages ​​(such as Java (TM), Smalltalk, C++ etc.) and traditional procedural programming languages ​​(such as " C " programming language or similar programming languages).The program code can be executed completely on the user's computer as an independent software package, partly on the user's computer, partly on the user's computer and partly on a remote computer, or completely on a remote computer or server.In the latter case, the remote computer can be connected to the user's computer through any type of network, and this network comprises local area network (LAN) or wide area network (WAN), or can be connected to an external computer (for example, by using the Internet of an Internet service provider).

[0032] Aspects of the present invention are described below with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the present invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, as well as combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor, particularly a microprocessor or central processing unit (CPU), of a general-purpose computer, a special-purpose computer, or other programmable data processing device to produce a machine, such that the instructions, executed by the processor of the computer, other programmable data processing device, or other device, create a device for implementing the functions / actions specified in the flowchart and / or one or more block diagram blocks.

[0033] These computer program instructions may also be stored in a computer-readable medium, which may direct a computer, other programmable data processing apparatus, or other device to operate in a specific manner so that the instructions stored in the computer-readable medium produce an article of manufacture including instructions (for implementing the functions / actions specified in the flowchart and / or one or more block diagram blocks).

[0034] The computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus, or other devices to produce a computer-implemented process, such that the instructions executed on the computer or other programmable apparatus provide a process for implementing the functions / actions specified in the flowchart and / or one or more block diagram blocks.

[0035] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of devices, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in the flowchart or block diagram may represent a module, code segment, or code portion that includes one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the blocks may not appear in the order noted in the figures. For example, two blocks shown in succession may actually be executed substantially simultaneously, or the blocks may sometimes be executed in the reverse order, depending on the functions involved. It will also be noted that each block in the block diagrams and / or flowchart illustrations, as well as combinations of blocks in the block diagrams and / or flowchart illustrations, may be implemented by a dedicated hardware-based system that performs the specified functions or actions, or a combination of dedicated hardware and computer instructions. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] These and other aspects of the invention will be apparent from and further elucidated, by way of example, with reference to the accompanying drawings, in which:

[0037] Figure 1 is a block diagram of an embodiment of a system;

[0038] Figure 2 Shown is the use of Figure 1 Examples of systems;

[0039] Figure 3 is a flow chart of a first embodiment of the method;

[0040] Figure 4 is a flow chart of a second embodiment of the method;

[0041] Figure 5 is a flowchart of a third embodiment of the method;

[0042] Figure 6 is a flowchart of a fourth embodiment of the method; and

[0043] Figure 7 is a block diagram of an exemplary data processing system for executing the method of the present invention.

[0044] Corresponding elements in the drawings are denoted by the same reference numerals. DETAILED DESCRIPTION

[0045] Figure 1 An embodiment of a system for detecting human presence based on changes in received radio frequency (RF) signals is shown. In this first embodiment, the system is a bridge 1. The bridge 1 includes a receiver 3, a transmitter 4, a processor 5, and a memory 7. The processor 5 is configured to cause a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic via the transmitter 4. Figure 1 In the example of FIG, one or more RF signals are transmitted by one or more of the lighting devices 31-37. The one or more RF signals are received by other lighting devices 31-37. For example, the lighting devices 31-37 may be Hue lights, and the bridge 1 may be a Hue bridge.

[0046] exist Figure 1 In the embodiment, bridge 1 uses transmitter 4 to instruct lighting devices 31-37 which transmission characteristics to use for transmitting RF signals and / or which reception characteristics to use for receiving RF signals, and optionally indicates whether to transmit or receive RF signals. Bridge 1 itself can also participate in presence sensing by transmitting (using transmitter 4) or receiving (using receiver 3) RF signals.

[0047] The processor 5 is further configured to: detect via the receiver 3 whether the change in the first set of radio frequency signals is caused by the presence of a human (or whether it is caused by the presence of a human or an animal), and detect via the receiver 3 whether the change in the first set of radio frequency signals has another cause. Figure 1 In this embodiment, processor 5 uses receiver 3 to receive data from lighting devices that receive RF signals. This data enables these detections. For example, this data may include signal strength or channel state information (CSI), or changes in signal strength or CSI. This data may be transmitted in the RF signal used for RF-based presence sensing, in other RF signals, or in non-RF signals. If bridge 1 itself also participates in presence sensing, it may analyze the strength of the RF signal or CSI received via receiver 3.

[0048] Processor 5 is further configured to, upon detecting that the change in the first set of radio frequency signals has an additional cause, cause a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic via transmitter 4. The second transmission characteristic is different from the first transmission characteristic, and the second reception characteristic is different from the first reception characteristic. Processor 5 is further configured to identify the additional cause based on the change in the second set of radio frequency signals and to provide, via transmitter 4, an output that includes or is dependent on the additional cause.

[0049] exist Figure 1In an embodiment of the invention, the processor 5 is configured to identify a further cause further based on data obtained from the motion sensor 39, which transmits data to the bridge 1. Figure 1 In the example shown, the output is provided to mobile device 19 via wireless LAN access point 17. For example, bridge 1 can be connected to wireless LAN access point 17 via Ethernet or Wi-Fi. Mobile device 17 can also control the settings (e.g., on / off, color, dimming level) of lighting devices 31-37 via wireless LAN access point 17 and bridge 1. Because the output is provided to a device with a display, the output typically includes an additional reason, for example, the output can be a message including the additional reason.

[0050] Alternatively or additionally, processor 5 may be configured to control one or more of lighting devices 31-37 via transmitter 4 in response to detecting human presence and / or in response to identifying another reason. In the former case, the user does not need to manually activate his lighting device(s). In the latter case, the lighting device(s) may be used, for example, to convey information (e.g., to alert the user).

[0051] The first group of one or more radio frequency signals and the second group of one or more radio frequency signals may differ in message rate, transmission frequency, duration and / or transmitting device. For example, the frequency may be increased from 2.4 GHz to 20 GHz to increase the absorption of RF radiation. The message rate indicates how often the radio frequency signals / messages are transmitted. By increasing the message rate of the transmitted RF signal and / or the duration of the RF signal, the detection accuracy is improved, but power consumption is also increased and the wireless network may become congested. The transmitting device and the receiving device may be selected so that the possible cause of the event is located between them. For example, the first and second reception characteristics may differ in the number of antennas used to receive the RF signal and / or in the receiving device(s).

[0052] exist Figure 1 In an embodiment of the present invention, the processor 5 is configured to determine the change in the radio frequency signal by comparing the signal strength of the radio frequency signal with the signal strength of a previous radio frequency signal received at a previous moment. In an alternative embodiment, the processor 5 is configured to determine the change in the radio frequency signal by comparing the signal strength of the radio frequency signal with the signal strength of a reference radio frequency signal received at a reference moment.

[0053] exist Figure 1In an embodiment, the processor 5 is configured to detect human presence and / or identify additional causes by comparing changes in the radio frequency signal with signatures of known causes. These signatures may be stored on an internet server 13 connected to the internet 11, which is similar to a wireless LAN access point 17. For example, additional causes may be a slow increase in a body of water, a sudden change in a body of water, a body of water moving between floors or rooms, a moving car, or a parked car.

[0054] The following use cases are examples of how to detect and identify events other than human presence in a house:

[0055] - Event detection in the bathroom. RF-based sensing can detect slowly increasing or decreasing bodies of water; this could be attributed to a bathtub filling or draining. It can also differentiate between showering, toilet flushing, and sink use based on measured water volume and movement; for example, flushing a toilet will result in rapid water movement. Lighting can then be controlled to provide better background illumination, or connected devices (e.g., HVAC systems, thermostats, music players, smart home systems, voice assistants) can be notified of the identified event.

[0056] Event detection in the living room or other rooms. RF-based sensing can detect, for example, a leak or overflow in a fish tank or aquarium. In this case, the lighting fixture can display a warning light effect (e.g., flashing red), or the alarm event can be provided to a connected system (e.g., a smartphone, smart home controller, or water / utility company server).

[0057] The following use cases are examples of how to detect and recognize events other than human presence outside a house:

[0058] - Event detection in the garden and around the house. Just like detecting a flushed toilet in a house, rain or sprinklers can be detected in the garden. RF-based sensing can also be used to detect passing cars and distinguish whether a car is parked in the driveway (in this use case, the change in signal is not due to absorption by water, but rather reflection by metal). If rain is detected, the outside lights can be brighter to increase visibility on the road, or the inside lights can turn blue to notify the user that they need an umbrella.

[0059] exist Figure 1In the illustrated embodiment of bridge 1, bridge 1 includes a single processor 5. In alternative embodiments, bridge 1 includes multiple processors. Processor 5 of bridge 1 can be a general-purpose processor (e.g., an ARM-based processor) or a specialized processor. For example, processor 5 of bridge 1 can run a Unix-based operating system. Memory 7 can include one or more memory cells. For example, memory 7 can include solid-state memory. For example, memory 7 can be used to store a list of connected lights.

[0060] The receiver 3 and transmitter 4 may use one or more wired or wireless communication technologies, such as Ethernet for communicating with the wireless LAN access point 17 and Zigbee for communicating with the lighting devices 31-37. In alternative embodiments, multiple receivers and / or multiple transmitters are used instead of a single receiver and a single transmitter. Figure 1 In the illustrated embodiment, a separate receiver and a separate transmitter are used. In an alternative embodiment, receiver 3 and transmitter 4 are combined into a transceiver. Bridge 1 may include other components typical of network equipment (such as power connectors). The present invention may be implemented using a computer program running on one or more processors.

[0061] exist Figure 1 In an embodiment, the system of the present invention comprises a bridge. In an alternative embodiment, the system of the present invention is a different device, such as a personal computer or a server computer or a lighting device. Figure 1 In an alternative embodiment, the system of the present invention comprises a plurality of devices.

[0062] Figure 2 Shown is the use of the house 41 Figure 1 1. Lighting device 31 is placed in the hallway on the ground floor of house 41. Lighting devices 32 and 33 are placed in the living room on the ground floor of house 41. Lighting devices 34 and 37 are placed in the bathroom on the second floor of house 41. Lighting device 35 is placed in the hallway on the second floor of house 41. Lighting device 36 is placed in the bedroom on the second floor of house 41. The RF signal transmitted by lighting device 32 and received by lighting devices 34 and 37 can be used, for example, to determine whether bathtub 43 is full or empty, whether bathtub 43 is being filled, whether bathtub 43 is being drained, and / or whether bathtub 43 is overflowing.

[0063] Motion sensor 39 is also placed in the living room on the ground floor of house 41. Motion sensor 39 can be used to help improve human presence detection. For example, if person 49 is in the living room and their presence is detected by RF-based sensing with the help of motion sensor 39, the detected large body of water can be determined to be that person 49, rather than a body of water moving between floors (e.g., a leak).

[0064] Figure 3 A first embodiment for detecting human presence based on changes in received radio frequency signals is shown. Step 101 includes causing a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic. For example, the method may be performed by a controller of a network presence sensing system. The network presence sensing system includes multiple sensing nodes, and the controller may be one of these nodes. For example, a lighting device may serve as a sensing node. Step 101 may include transmitting a message to (other) sensing nodes and / or may include transmitting radio frequency signals with the first transmission characteristic and / or receiving radio frequency signals with the first reception characteristic.

[0065] Step 102 includes determining a change in a first set of radio frequency signals.A network presence sensing system monitors a space by continuously sending RF messages between nodes and measuring any deviations from expected (eg, calibrated) signal strengths.

[0066] Step 103 includes detecting whether the change in the first set of radio frequency signals is caused by the presence of a human (or whether it is caused by the presence of a human or an animal). Figure 3 In the embodiment of the present invention, step 105 is performed only when human presence is detected. If human presence is not determined in step 103, step 101 is repeated.

[0067] Step 105 includes detecting whether the change in the first set of radio frequency signals has another cause. In step 105, it is only determined whether the change has another cause, but it is not yet possible to determine what the other cause is. Figure 3 In an embodiment, if it is determined in step 105 that the change does not have another cause, this means that human presence is the only cause, and step 101 is repeated. If it is determined in step 105 that the change does have another cause, step 107 is performed. In an alternative embodiment, step 105 is omitted, and step 107 is performed immediately after step 103.

[0068] Based on the data collected by the sensing nodes, the likelihood that the detected deviation is caused by a person (the most frequent event) is estimated in step 103. If the event is classified as the movement or presence of a person, a default action (such as turning on a light) is activated. Otherwise, more data is collected to distinguish this event from other events in the set of possible events.

[0069] Step 107 includes causing a second set of one or more radio frequency signals to be transmitted with a second transmit characteristic and / or received with a second receive characteristic. The second transmit characteristic is different from the first transmit characteristic, and the second receive characteristic is different from the first receive characteristic. After step 107, step 102 is performed again, this time to determine a change in the second set of radio frequency signals.

[0070] After detecting the first deviation in the RF signal, the RF signal may be transmitted more frequently and / or for a longer duration, thereby enabling more accurate classification of the event, for example, by detecting whether there is a continuous or sudden change in the deviation (which may provide more information for classification). More frequent messages will allow for faster and more accurate detection of events, but will consume more energy (in the case of battery-powered devices) and may interfere with the normal operation of the network (for example, for a connected lighting system, interfering with the RF messages sent to control the lights).

[0071] Step 109 involves identifying additional causes based on the changes in the second set of RF signals. For example, if the changes in the RF signals cannot be attributed to a person, for example because the detected movement could not be caused by a person (e.g., a body of water moving through a ceiling from one floor to another), the most likely event could be a toilet flushing, a leak, etc. If the body of water is too large to be a person, it could be a bathtub. If the body of water changes gradually (increasing or decreasing), it could be a leak, a bathtub draining, or a bathtub filling. If the body of water appears simultaneously in several locations and remains stable, it could be rain or a sprinkler (e.g., if detected in a garden).

[0072] Information about the location of the sensing nodes (e.g., room type) can be used to better classify events. For example, a bathtub filling is more likely to be detected by an RF device in a bathroom, while rainwater is more likely to be detected by an RF device in a garden.

[0073] Additionally, neighboring areas can also be used to (at least partially) confirm the conclusion about the first room. For example, room A (e.g., Figure 2 The water flow in the second floor bathroom in the middle will cause the RF signal in that room to increase / decrease slowly and almost uniformly throughout the room. However, in room B (e.g. Figure 2 In the living room on the middle ground floor, only the lights close to the wall shared with room A (e.g. Figure 2 32) will see a similar or smaller slow increase / decrease, while lights further away (e.g. Figure 2 While this behavior may not make sense to Room B (since it doesn't really fit any known pattern), it can be seen as confirmation of what may have happened in Room A.

[0074] Additionally, historical information can be used for the same space or adjacent spaces to aid in classification in step 109. For example, other areas can be used to track previous events (e.g., movement) to see if the change can be explained by the movement of a person, or to see if the water volume has increased compared to a previous event / moment.

[0075] Step 110 includes determining whether an additional cause can be identified in step 109. If an additional cause cannot be identified in step 109, step 101 or step 107 is repeated. If it is determined in step 102 that there is no change in the second set of RF signals, or if the change determined in step 102 is caused by human presence, step 101 is repeated. Otherwise, step 107 is repeated with the same or different second transmit characteristics and / or second receive characteristics. If an additional cause can be identified in step 109, step 111 is performed. Step 111 includes providing an output that includes or depends on the additional cause.

[0076] In step 111, depending on the user and / or system, the lighting devices can be controlled according to specific light settings. For example, a specific light scene associated with the detected event (e.g., a relaxing scene in the bathroom if a bathtub is detected filling, or a flashing warning light in the event of a leak). In addition to or instead of lighting, a message can be sent to the user, or the state and / or behavior of other connected systems can be changed.

[0077] Figure 4 A second embodiment of detecting human presence based on changes in received radio frequency signals is shown. Figure 4 In the embodiment, Figure 3 Compared to the embodiment of FIG. 1 , step 105 is performed regardless of whether human presence is detected in step 103. Therefore, even if human presence is not detected, another reason may be detected. Figure 4 In the embodiment, Figure 3 Step 109 is replaced by step 121. Step 121 includes identifying an additional reason based on the change in the second set of radio frequency signals and based on whether human presence is detected in step 103. In an alternative embodiment, Figure 4 Step 121 is Figure 3 Step 109 is replaced.

[0078] Figure 5 A third embodiment for detecting human presence based on changes in received radio frequency signals is shown. Step 101 includes causing one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic. If changes are present in the radio frequency signals, step 102 is performed and includes determining the changes in the radio frequency signals. Step 103 includes detecting whether the changes in the radio frequency signals are caused by human presence. Step 105 includes detecting whether the changes in the radio frequency signals have another cause. If, in step 105, it is determined that the changes do not have another cause, step 101 is repeated.

[0079] If it is determined in step 105 that the changes do have another cause, step 121 is performed. Step 121 includes identifying another cause based on the changes in the radio frequency signal and based on whether human presence was detected in step 103. Step 110 includes determining whether another cause can be identified in step 121.

[0080] If no further cause is identified in step 121, step 107 is performed. Step 107 includes causing one or more radio frequency signals to be transmitted with a second transmit characteristic and / or received with a second receive characteristic. The second transmit characteristic is different from the first transmit characteristic, and the second receive characteristic is different from the first receive characteristic. After step 107, step 102 is repeated, but now for the new one or more radio frequency signals.

[0081] If a further cause can be identified in step 121, step 111 is performed. Step 111 comprises providing an output comprising or dependent upon the further cause. Step 101 is repeated after step 111 to again prioritize human presence detection.

[0082] Therefore, in Figure 5 In an embodiment of the present invention, an attempt is made to identify a further cause based on one or more radio frequency signals transmitted with the first transmission characteristic and / or received with the first reception characteristic, and not only based on one or more radio frequency signals transmitted with the second transmission characteristic and / or received with the second reception characteristic. Figure 5 In an embodiment of the present invention, it is attempted to detect human presence based on one or more radio frequency signals transmitted with the second transmission characteristic and / or received with the first reception characteristic, rather than solely based on one or more radio frequency signals transmitted with the first transmission characteristic and / or received with the second reception characteristic.

[0083] Figure 6 A fourth embodiment for detecting human presence based on changes in received radio frequency signals is shown. This fourth embodiment is an extension of the first embodiment. Step 101 includes causing a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic. Step 102 includes determining changes in the first set of radio frequency signals. Step 103 includes detecting whether the changes in the first set of radio frequency signals are caused by human presence. Figure 6 In the embodiment, similar to Figure 3 In the embodiment of the present invention, step 105 is performed only when human presence is detected. If human presence is not determined in step 103, step 101 is repeated.

[0084] Step 105 includes detecting whether the change in the first set of radio frequency signals has another cause. If it is determined in step 105 that the change does have another cause, steps 131 and 107 are performed. Step 131 includes obtaining data from one or more further sensors.

[0085] Step 107 includes causing a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic. The second transmission characteristic is different from the first transmission characteristic and / or received with the second reception characteristic. After step 107, step 102 is performed again, this time to determine a change in the second set of radio frequency signals.

[0086] Step 133 includes identifying additional causes based on the changes in the second set of radio frequency signals determined in the previous step 102 and the data obtained from one or more additional sensors in the previous step 131. Step 110 includes determining whether additional causes can be identified in step 133. Figure 6 In the embodiment, if no further cause can be identified in step 133, step 101 is repeated. In an alternative embodiment, either step 101 is repeated or steps 131 and 107 are repeated, similar to Figure 3 An embodiment, wherein step 101 or step 107 is repeated after step 110.

[0087] If additional causes can be identified in step 109, step 111 is performed. Step 111 includes providing an output that includes or depends on the additional causes. Next, steps 135 and 137 are performed. Step 135 includes receiving user feedback. Step 137 includes using the user feedback to improve the software that identifies additional causes, i.e., the software that implements step 133. This learning cycle can be used to improve the user's own system, as well as the systems of other users.

[0088] exist Figure 6 In an embodiment, the user feedback received in step 135 includes user behavior, and this behavior is used to determine whether the alternative cause has been correctly identified. More specifically, if the user adjusts the setting immediately after controlling the lighting device using the light setting corresponding to the identified alternative cause, this may indicate that the identification of the alternative cause or the associated light setting is incorrect. This information can be used to improve step 133 or, alternatively, trigger the system to request clarification from the user. In a similar manner, a user can train the system by indicating when they initiate a certain event (e.g., filling a bathtub), and recording the signals following the event so that these signal patterns can be associated with the event.

[0089] exist Figure 6 In the embodiment, Figure 3There are two main changes compared to the embodiment of FIG: a) step 131 is added and step 109 is replaced by step 133; and b) steps 135 and 137 are added. In an alternative embodiment, only one of these changes is performed.

[0090] exist Figures 3 to 6 In alternative embodiments, step 101 is repeated after step 111 or step 137. In these embodiments, human presence detection is prioritized again after an additional cause is identified. In alternative embodiments, step 107 is repeated after step 111 or step 137 until there is no longer a change in the RF signal or the change in the RF signal no longer has a cause other than human presence. In this alternative embodiment, step 111 may include providing an output only if the same additional cause was not previously identified (e.g., if step 111 includes transmitting a message). Alternatively, if step 101 is repeated instead of step 107, a message is transmitted.

[0091] Figure 7 Describes how the instructions can be executed as referenced Figures 3 to 6 A block diagram of an exemplary data processing system for describing the method.

[0092] like Figure 7 As shown, data processing system 300 may include at least one processor 302 coupled to memory element 304 via system bus 306. Thus, the data processing system may store program code within memory element 304. Additionally, processor 302 may execute program code accessed from memory element 304 via system bus 306. In one aspect, the data processing system may be implemented as a computer adapted to store and / or execute program code. However, it should be appreciated that data processing system 300 may be implemented in the form of any system including a processor and memory capable of performing the functions described herein.

[0093] Memory element 304 may include one or more physical memory devices, such as, for example, local memory 308 and one or more mass storage devices 310. Local memory may refer to random access memory or other non-permanent memory devices that are typically used during the actual execution of program code. Mass storage devices may be implemented as hard drives or other permanent data storage devices. Processing system 300 may also include one or more cache memories (not shown) that provide temporary storage of at least some program code in order to reduce the number of times program code must be retrieved from mass storage device 310 during execution. For example, if processing system 300 is part of a cloud computing platform, processing system 300 may also be able to use memory elements of another processing system.

[0094] Input / output (I / O) devices, depicted as input device 312 and output device 314, may optionally be coupled to the data processing system. Examples of input devices may include, but are not limited to, a keyboard, a pointing device such as a mouse, a microphone (e.g., for sound and / or voice recognition), etc. Examples of output devices may include, but are not limited to, a monitor or display, speakers, etc. Input and / or output devices may be coupled to the data processing system directly or through intervening I / O controllers.

[0095] In an embodiment, the input and output devices may be implemented as a combined input / output device (in Figure 7 314). An example of such a combination device is a touch-sensitive display, sometimes referred to as a "touch screen display" or simply a "touch screen." In such an embodiment, input to the device can be provided by moving a physical object (such as, for example, a stylus or finger of a user) across or near the touch screen display.

[0096] Network adapter 316 may also be coupled to the data processing system to enable it to couple to other systems, computer systems, remote network devices, and / or remote storage devices through intervening private or public networks. The network adapter may include a data receiver for receiving data transmitted to data processing system 300 by the system, device, and / or network, and a data transmitter for transmitting data from data processing system 300 to the system, device, and / or network. Modems, cable modems, and Ethernet cards are examples of different types of network adapters that may be used with data processing system 300.

[0097] like Figure 7 As shown, memory element 304 can store applications 318. In various embodiments, applications 318 can be stored in local memory 308, one or more mass storage devices 310, or separate from local memory and mass storage devices. It should be appreciated that data processing system 300 can further execute an operating system ( Figure 7 318. The application 318, implemented in the form of executable program code, may be executed by data processing system 300, for example, by processor 302. In response to executing the application, data processing system 300 may be configured to perform one or more operations or method steps described herein.

[0098] Figure 7Input device 312 and output device 314 are shown as separate from network adapter 316. However, additionally or alternatively, input can be received via network adapter 316, and output can be transmitted via network adapter 316. For example, data processing system 300 can be a cloud server. In this case, the input can be received from a user device acting as a terminal, and the output can be transmitted to the user device acting as a terminal.

[0099] Various embodiments of the present invention can be implemented as a program product for use with a computer system, wherein the program(s) of the program product define the functionality of the embodiments (including the methods described herein). In one embodiment, the program(s) may be embodied on various non-transitory computer-readable storage media, where, as used herein, the term "non-transitory computer-readable storage medium" includes all computer-readable media with the sole exception of transitory propagated signals. In another embodiment, the program(s) may be embodied on various transitory computer-readable storage media. Illustrative computer-readable storage media include, but are not limited to: (i) non-writable storage media on which information is permanently stored (e.g., read-only memory devices within a computer, such as CD-ROM disks readable by a CD-ROM drive, ROM chips, or any type of solid-state non-volatile semiconductor memory); and (ii) writable storage media on which variable information is stored (e.g., flash memory, a floppy disk within a floppy disk drive or hard drive, or any type of solid-state random-access semiconductor memory). The computer program(s) may be executed on the processor 302 described herein.

[0100] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the present invention. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that the terms "include" and / or "comprise," when used in this specification, specify the presence of stated features, parts, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, parts, steps, operations, elements, components, and / or combinations thereof.

[0101] The corresponding structures, materials, acts, and equivalents of all means or step plus function elements in the claims below are intended to include any structure, material, or act for performing the function in combination with other claimed elements as specifically claimed. The description of the embodiments of the present invention is provided for illustrative purposes and is not intended to be exhaustive or limited to the implementation in the form disclosed. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the invention. The embodiments are chosen and described in order to best explain the principles of the invention and some practical applications, and to enable others skilled in the art to understand the invention for various embodiments with various modifications as are suitable for the particular use contemplated.

Claims

1. A lighting system (1) for detecting human presence based on changes in received radio frequency signals, the system (1) comprising: at least one input interface (3); at least one output interface (4); as well as At least one processor (5) configured to: - causing a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic via the at least one output interface (4), - detecting via the at least one input interface (3) whether a change in the first set of radio frequency signals is caused by the presence of a human (49), - detecting via the at least one input interface (3) whether the change in the first set of radio frequency signals has another cause, characterized in that upon detecting that the change in the first group of radio frequency signals has a further cause, causing, via the at least one output interface (4), a second group of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or to be received with a second reception characteristic, the second transmission characteristic being different from the first transmission characteristic and the second reception characteristic being different from the first reception characteristic, and wherein the second transmission characteristic and / or the second reception characteristic of the second group of radio frequency signals are optimized to identify the further cause; - identifying said further cause based on a change in said second set of radio frequency signals, and - providing an output comprising or depending on the further cause via the at least one output interface (4); wherein the at least one processor (5) is configured to detect the presence of the human (49) and / or identify the further cause by comparing the change in the radio frequency signal with signatures of known causes.

2. The lighting system (1) according to claim 1, wherein the at least one processor (5) is configured to transmit a message comprising the further cause via the at least one output interface (4).

3. A lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to: control the lighting device (31-37) via the at least one output interface (4) in response to detecting the presence of the human (49) and / or in response to identifying the further reason.

4. The lighting system (1) according to claim 1 or 2, wherein the first set of one or more radio frequency signals and the second set of one or more radio frequency signals differ in message rate, transmission frequency, duration, content and / or transmission device.

5. The lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to determine the change of the radio frequency signal by comparing the signal strength of the radio frequency signal with the signal strength of a previous radio frequency signal received at a previous moment.

6. The lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to determine the change of the radio frequency signal by comparing the signal strength of the radio frequency signal with the signal strength of a reference radio frequency signal received at a reference time.

7. The lighting system (1) according to claim 1 or 2, wherein the further cause is a slow increase in a body of water, a sudden change in a body of water, a body of water moving between floors, a moving car or a parked car.

8. The lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to identify the further cause further based on data obtained from one or more further sensors (39).

9. The lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to detect the presence of a further human (49) based on the second set of radio frequency signals.

10. The lighting system (1) according to claim 1 or 2, wherein the at least one processor (5) is configured to receive user feedback via the at least one input interface (3) and to use the user feedback to improve the method step of identifying the further cause.

11. A method for detecting human presence based on changes in received radio frequency signals, the method comprising: - causing (101) a first set of one or more radio frequency signals to be transmitted with a first transmission characteristic and / or received with a first reception characteristic; - detecting (103) whether a change in the first set of radio frequency signals is caused by human presence; - detecting (105) whether said change in said first set of radio frequency signals has another cause; - upon detecting that the change in the first set of radio frequency signals has a further cause, causing (107) a second set of one or more radio frequency signals to be transmitted with a second transmission characteristic and / or received with a second reception characteristic, the second transmission characteristic being different from the first transmission characteristic and the second reception characteristic being different from the first reception characteristic, and wherein the second transmission characteristic and / or the second reception characteristic of the second set of radio frequency signals are optimized to identify the further cause; - identifying (109, 121, 133) the further cause based on a change in the second set of radio frequency signals; and - providing (111) an output including or dependent on said further cause; wherein said detecting of the presence of a human (49) and / or said identifying of said further cause is performed by comparing said change in said radio frequency signal with signatures of known causes.

12. A computer program product storing at least one software code portion configured to perform the method of claim 11 when run on a computer system having a processor according to claim 1.

Images