Sensor device with ultrasonic receiving circuit

Abstract

The sensor device may include a signal generator circuit configured to generate a supplemental signal combined with an ultrasonic receive voltage signal generated by the ultrasonic receive element in response to the received ultrasonic waves. The sensor device may include an ultrasonic receive circuit configured to receive a combination of the ultrasonic receive voltage signal and the supplemental signal, and generate a detection signal indicating when a space is occupied. The sensor device may also include a control circuit configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal. The combination of the supplemental signal and the ultrasonic reception voltage signal can ensure that the magnitude of the signal processed by the ultrasonic reception circuit is sufficiently large so that the ultrasonic reception circuit can appropriately generate the detection signal, and the control circuit can detect the occupancy condition.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 339,211 filed on May 6, 2022, the entire disclosure of which is incorporated herein by reference. Background Art

[0003] Occupancy and vacancy sensors are typically used to detect occupancy and / or vacancy conditions within a space to control electrical loads such as lighting loads. Occupancy sensors typically operate to turn on lighting loads when the occupancy sensor detects the presence of a user in the space (e.g., an occupancy condition), and then turn off the lighting loads when the occupancy sensor detects that the user has left the space (e.g., a vacancy condition). Vacancy sensors are typically used to turn off lighting loads when the vacancy sensor detects that the space is vacant. Therefore, when a vacancy sensor is used, the lighting loads must be turned on manually (e.g., in response to manual actuation of a control actuator).

[0004] Occupancy and vacancy sensors have been provided in wall mounted load control devices that are coupled between an alternating current (AC) power source and an electrical load for controlling the amount of electricity delivered to the electrical load. Other occupancy and vacancy sensors have been provided as part of a lighting control system. These sensors can be coupled to a lighting controller (e.g., a central processor) via a wired control link, which then controls the lighting load accordingly. Other sensors can be battery powered and can be operable to transmit wireless signals such as radio frequency (RF) signals to the lighting controller or directly to a load control device such as a dimmer switch. Occupancy and vacancy sensors in a lighting control system can be mounted high on a ceiling or wall. Thus, occupancy and vacancy sensors can be positioned in an optimal location to detect the presence of users in all areas of the space.

[0005] Occupancy and / or vacancy sensors typically include an internal detector, such as a pyroelectric infrared (PIR) detector, and a lens for directing energy to the internal detector to detect the presence of a user in the space. In addition, some occupancy and vacancy sensors also include an ultrasonic receiving circuit for detecting the presence of a user in the space. Such ultrasonic sensors can transmit ultrasonic waves at a predetermined frequency and analyze the received ultrasonic waves to determine whether there are occupants in the space. The received ultrasonic waves generated by reflection from a moving object may have a Doppler shift characteristic relative to the transmitted ultrasonic waves, while the received ultrasonic waves generated by reflection from stationary objects in the room (e.g., walls, ceilings, floors, and other stationary objects) may not have a Doppler shift. Therefore, if there is a Doppler shift between the frequencies of the transmitted and received ultrasonic waves, the ultrasonic sensor is able to determine whether there are occupants in the space. Summary of the invention

[0006] As described herein, a sensor device may include: an ultrasonic receiving element configured to receive ultrasonic waves and generate an ultrasonic receiving voltage signal; and a control circuit configured to control the generation of a supplementary signal combined with the ultrasonic receiving voltage signal. When the space is vacant, the ultrasonic wave may include a non-Doppler shifted ultrasonic wave, and when the space is occupied, the ultrasonic wave may include a combination of a non-Doppler shifted ultrasonic wave and a Doppler shifted wave. The non-Doppler shifted ultrasonic wave may be characterized by an ultrasonic frequency. The supplementary signal may also be characterized by the same ultrasonic frequency. The sensor device may include an ultrasonic receiving circuit configured to receive a combination of an ultrasonic receiving voltage signal and a supplementary signal, and generate a detection signal indicating when the space is occupied. The control circuit may be configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal. The combination of the supplementary signal and the ultrasonic receiving voltage signal can ensure that the magnitude of the signal processed by the ultrasonic receiving circuit is large enough so that the ultrasonic receiving circuit can appropriately generate the detection signal, and the control circuit can detect the occupancy condition in the space.

[0007] In addition, the sensor device may further include a signal generator circuit configured to generate a supplementary signal. The control circuit may be configured to generate a signal generation control signal, which is received by the signal generator circuit to control the generation of the supplementary signal. For example, the control circuit may pulse width modulate the signal generation control signal at an ultrasonic frequency. The control circuit may control the signal generation control signal to enable and disable the signal generator circuit. The control circuit may enable the signal generator circuit to generate a supplementary signal in a first mode (e.g., a large space mode), and disable the signal generator circuit to stop generating a supplementary signal in a second mode (e.g., a small space mode). The control circuit may determine to operate in one of the first mode and the second mode in response to actuation of the actuator and / or in response to a message received via the communication circuit.

[0008] In addition, the control circuit may be configured to automatically determine to operate in one of the first mode and the second mode, for example, in response to a monitoring voltage of the ultrasonic receiving circuit. The monitoring voltage may have a magnitude indicating that the ultrasonic receiving signal (e.g., when the signal generator circuit is disabled) or a combination of the ultrasonic receiving voltage signal and the supplemental signal (e.g., when the signal generator circuit is enabled) may be properly processed by the ultrasonic receiving circuit to generate a detection signal. For example, the control circuit may be configured to receive the monitoring voltage and, when the signal generator circuit is disabled, determine to operate in the large spatial mode when the magnitude of the monitoring voltage indicates that the ultrasonic receiving signal may not be properly processed by the ultrasonic receiving circuit to generate a detection signal.

[0009] The control circuit may also be configured to control the phase of the signal generation control signal to control the phase of the supplementary signal. When the control circuit determines that the supplementary signal is out of phase with the received ultrasonic wave (e.g., the phase difference is about 180 degrees), the control circuit may adjust the phase of the supplementary signal, and adjust the phase of the supplementary signal until the control circuit determines that the supplementary signal is not out of phase with the received ultrasonic wave (e.g., the phase difference is about 180 degrees). The control circuit may receive a monitoring voltage and measure a first magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generation circuit is disabled, measure a second magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generation circuit is enabled, and determine the phase of the adjustment signal generation control signal when the second magnitude of the monitoring voltage is less than the first magnitude of the monitoring voltage. The control circuit may adjust the phase of the supplementary signal until the second magnitude of the monitoring voltage is approximately equal to a magnitude that can be properly processed by the ultrasonic receiving circuit to generate a detection signal (e.g., such as the first magnitude of the monitoring voltage).

[0010] The signal generator circuit may be configured to generate a supplementary signal as a sinusoidal signal at an ultrasonic frequency in response to a signal generation control signal. The control circuit may be configured to adjust the peak-to-peak magnitude of the supplementary signal in response to a noise floor of a detection signal generated by the ultrasonic receiving circuit. The control circuit may be configured to determine the noise floor of the detection signal in response to the magnitude of the detection signal. The control circuit may be configured to automatically adjust the peak-to-peak magnitude of the supplementary signal in response to the noise floor of the detection signal when the space is vacant. The control circuit may be configured to adjust the peak-to-peak magnitude of the supplementary signal to a first magnitude when the magnitude of the noise floor of the detection signal is less than a threshold, and to adjust the peak-to-peak magnitude of the supplementary signal to a second magnitude when the magnitude of the noise floor of the detection signal is greater than a threshold, wherein the second magnitude is less than the first magnitude. The control circuit may be configured to adjust the peak-to-peak magnitude of the supplementary signal according to the magnitude of the noise floor of the detection signal.

[0011] In addition, the sensor device may include a housing for accommodating an ultrasonic receiving element, a signal generator circuit, an ultrasonic receiving circuit, and a control circuit. The housing may include an opening in a front surface of the housing. The ultrasonic receiving element may be configured to receive ultrasonic waves through the opening. The diameter of the opening may be approximately equal to the wavelength of the ultrasonic wave, and the depth between the front surface of the housing and the ultrasonic receiving element may be approximately equal to one-quarter of the wavelength of the ultrasonic wave.

[0012] In some examples, the sensor device may include: a first ultrasonic receiving element and a second ultrasonic receiving element, the first ultrasonic receiving element and the second ultrasonic receiving element being configured to receive ultrasonic waves and generate corresponding first ultrasonic receiving voltage signals and second ultrasonic receiving voltage signals; and a first ultrasonic receiving circuit and a second ultrasonic receiving circuit, the first ultrasonic receiving circuit and the second ultrasonic receiving circuit being configured to receive corresponding first ultrasonic receiving voltage signals and second ultrasonic receiving voltage signals. The first ultrasonic receiving circuit and the second ultrasonic receiving circuit may be configured to generate corresponding first detection signals and second detection signals in response to corresponding first ultrasonic receiving voltage signals and second ultrasonic receiving voltage signals, both of which indicate when the space is occupied. The control circuit may be configured to receive the first detection signal and the second detection signal. The control circuit may be further configured to detect an occupancy condition in the space in response to the first detection signal and the second detection signal, only in response to the first detection signal or only in response to the second detection signal. For example, the control circuit may be configured to determine whether to respond to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal in response to at least one of the actuation of an actuator of the sensor device or a message received by the sensor device. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1A is a diagram of an exemplary load control system having a sensor device with an ultrasonic transmitting element and an ultrasonic receiving element.

[0014] Figure 1B is a schematic diagram of another exemplary load control system having a sensor device with an ultrasonic receiving element and an external ultrasonic transmitting device.

[0015] Figure 1C Such as Figure 1A A perspective view of an exemplary sensor arrangement of a sensor arrangement is shown.

[0016] Figure 2A is a block diagram of an exemplary sensor device.

[0017] Figure 2B is a block diagram of an exemplary sensor device including a signal generating circuit for generating a supplemental signal.

[0018] Figure 3 is a schematic diagram of an exemplary sensor device including a signal generating circuit for generating a supplemental signal.

[0019] Figure 4 is a flow chart of an exemplary process that may be performed by a sensor device for detecting occupancy and / or vacancy conditions in a space.

[0020] Figures 5 to 11is a flow chart of an exemplary process that may be performed to configure a sensor device for detecting occupancy and / or vacancy conditions in a space. DETAILED DESCRIPTION

[0021] Figure 1A 1 is a diagram of an exemplary load control system 100 having a load control device 110 (e.g., a dimmer switch and / or an electronic switch) and a sensor device 120. The load control device 110 can be coupled in series electrical connection between a power source (e.g., an alternating current (AC) power source 102) and an electrical load (e.g., a lighting load 104) for controlling the amount of power delivered to the lighting load 104, thereby controlling the intensity of the lighting load 104. For example, the load control device 110 can be suitable for installation in an electrical wall box, plugged into an electrical outlet, and / or remotely mounted (e.g., mounted to a junction box above a ceiling and / or inside a wall). The load control device 110 can include a panel 112 and a bezel 113 received in an opening of the panel. The load control device 110 can also include a switching actuator 114 (e.g., a button) and an intensity adjustment actuator 116. Continuous actuation of the switching actuator 114 switches (e.g., can turn off and on) the lighting load 104. Actuation of the upper portion 116A or the lower portion 116B of the intensity adjustment actuator 116 can increase or decrease the amount of power delivered to the lighting load 104, respectively, thereby increasing the intensity of the lighting load 104 from a minimum intensity (e.g., about 1%) to a maximum intensity (e.g., about 100%) or decreasing the intensity from the maximum intensity to the minimum intensity. A plurality of visual indicators 118 (e.g., light emitting diodes (LEDs)) can be arranged in a linear array on the left side of the bezel 113. The visual indicators 118 can be illuminated to provide feedback about the intensity of the lighting load 104.

[0022] The sensor device 120 may be mounted, for example, to a ceiling or wall near (e.g., in the surrounding space) a lighting load 104 controlled by the load control device 110, such that the sensor device 120 may be configured to detect an occupancy condition (e.g., the presence of an occupant) and / or a vacancy condition (e.g., the absence of an occupant) near the lighting load. The load control system 100 may include additional sensor devices 120 spaced apart to detect occupancy and / or vacancy conditions in different areas of the space surrounding the lighting load 104. The sensor device 120 may be configured to generate one or more control signals in response to detecting an occupancy condition and / or vacancy condition in the space surrounding the lighting load 104. For example, the sensor device 120 may be configured to generate an analog control signal (e.g., via a contact closure output circuit) that may be in one of two states, depending on the detection of an occupancy condition or a vacancy condition. In addition, the sensor device 120 can be configured to transmit a message (e.g., a digital message) to the load control device 110 wirelessly via a wireless signal such as a radio frequency (RF) signal 106 and / or via a wired communication link (not shown) in response to detecting an occupancy condition and / or a vacancy condition in the space surrounding the lighting load 104. The sensor device 120 can be battery powered and / or can be connected to an external power source, such as an AC power source 102 and / or a direct current (DC) power supply (not shown). The load control device 110 can be configured to turn on the lighting load 104 in response to receiving an indication of an occupancy condition from the sensor device 120, and to turn off the lighting load 104 in response to receiving an indication of a vacancy condition from the sensor device 120.

[0023] The sensor device 120 may include an occupancy detection circuit, such as an ultrasonic detection circuit including an ultrasonic transmitting element and / or an ultrasonic receiving element, which may be housed in a housing 122. The housing 122 may include a first opening 124 and a second opening 126, the first opening being used to allow ultrasonic waves 108 to be transmitted from the sensor device 120 through the ultrasonic transmitting element, and the second opening being used to allow the ultrasonic waves to be received by the ultrasonic receiving element inside the sensor device 120. The sensor device 120 may be configured to determine whether an occupied condition and / or a vacant condition currently occurs in the space in response to the ultrasonic waves 108 received by the ultrasonic receiving element, as will be described in more detail below. For example, the ultrasonic waves 108 may be transmitted by the sensor device 120 at an ultrasonic transmission frequency f US (e.g., approximately 40kHz) transmission.

[0024] The ultrasonic wave 108 emitted by the sensor device 120 may be reflected by an object in the space and returned to the sensor device 120. The emitted ultrasonic wave 108 may be reflected by a stationary object in the space and a moving object in the space. The ultrasonic wave 108 reflected from the stationary object may be an ultrasonic wave at an ultrasonic emission frequency fUS The ultrasonic wave 108 reflected from the moving object may not be at the ultrasonic wave transmission frequency f US is characterized by a frequency shift (e.g., a Doppler shift) that can indicate movement in the space (e.g., can indicate an occupancy condition). For example, ultrasound waves 108 reflected from a moving object can be Doppler shifted by a frequency f DS The sensor device 120 may receive the reflected ultrasonic wave 108, which may be a sum of a Doppler shifted reflected wave (e.g., reflected from a moving object) and a non-Doppler shifted reflected wave (e.g., reflected from a stationary object).

[0025] Although in Figure 1A Although not shown in the drawings, the sensor device 120 may also include a second pair of ultrasonic elements on the opposite side of the sensor device 120 (e.g., another ultrasonic transmitting element and another ultrasonic receiving element with corresponding openings). The additional ultrasonic transmitting elements and ultrasonic receiving elements may allow the sensor device 120 to have additional occupancy and / or vacancy detection coverage. The sensor device 120 may be configured to detect occupancy and / or vacancy conditions (e.g., both ultrasonic detection signals, only the first ultrasonic detection signal, or only the second ultrasonic detection signal) using two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, only the first pair of ultrasonic transmitting elements and ultrasonic receiving elements, or only the second pair of ultrasonic transmitting elements and ultrasonic receiving elements. In addition, the sensor device 120 may include a third or fourth pair of ultrasonic transmitting elements and ultrasonic receiving elements and corresponding openings.

[0026] Since the sensor device 120 can be located closer to an object in the space when the sensor device 120 is installed in a small space, the magnitude of the received ultrasonic wave 108 can be relatively large compared to when the sensor device 120 is installed in a large space. The sensor device 120 can be configured to operate in a small space mode (e.g., a large signal mode) and a large space mode (e.g., a small signal mode). When in the small space mode, the sensor device 120 can be configured to receive and process ultrasonic waves 108 with relatively large magnitudes (e.g., when the sensor device 120 is installed in a small space). When in the large space mode, the sensor device 120 can be configured to receive and process ultrasonic waves 108 with relatively small magnitudes (e.g., when the sensor device 120 is installed in a large space).

[0027] In some examples, the sensor device 120 may also include additional sensing circuits (e.g., additional occupancy detection circuits) for detecting occupancy and / or vacancy conditions in the space. Such sensor devices may be referred to as "dual technology" sensor devices. For example, the sensor device 120 may include an internal passive infrared (PIR) detection circuit with a pyroelectric detector, which may be configured to receive infrared energy from an occupant in the space via a lens 129 located on the housing 122. The sensor device 120 may be configured to detect occupancy and / or vacancy conditions in the space around the lighting load 104 in response to one or both of the ultrasonic detection circuit and the PIR detection circuit. Since the PIR detection circuit can use a different technology from the ultrasonic detection circuit, the dual technology occupancy sensor can provide an enhanced ability to detect the presence of an occupant in the space around the sensor device 120. In addition, the additional sensing circuits of the sensor device 120 may also include, for example, microwave detection circuits, millimeter wave radars, or any suitable detector or combination of detectors. Examples of sensor devices having PIR detection circuits are described in greater detail in U.S. Patent No. 7,940,167, issued May 20, 2011, and entitled “BATTERY-POWERED OCCUPANCY SENSOR,” the entire disclosure of which is hereby incorporated herein by reference.

[0028] For example, the sensor device 120 may perform a configuration process (e.g., a calibration process) to configure the operation of the sensor device 120, for example, in the space in which the sensor device 120 is installed. For example, during the configuration process, the sensor device 120 may be configured to operate in one of the small space mode and the large space mode during the configuration of the sensor device. In addition, the sensor device 120 may be configured to use two pairs of ultrasonic emitting elements and ultrasonic receiving elements during the configuration process, or to use one or the other pair of ultrasonic emitting elements and ultrasonic receiving elements. For example, the sensor device 120 may be configured to perform the configuration process in response to manual input (e.g., in response to the actuation of a button on the sensor device 120) and / or in response to a received message (e.g., transmitted in response to the actuation of a button on a remote control and / or a soft button on a display of a mobile device such as a smart phone or tablet). In addition, the sensor device 120 may be configured to automatically perform the configuration process (e.g., as described in more detail below). For example, the sensor device 120 may be configured to perform a configuration process periodically (e.g., once a month) when the space in which the sensor device is located is vacant (e.g., as determined in response to the ultrasonic detection circuit and / or the PIR detection circuit). The configuration process may be an initial configuration process performed when the objects in the space are in their expected positions after installation and the space is vacant. In addition, the configuration process may be a maintenance (e.g., recalibration) process performed (e.g., periodically) after the initial execution of the configuration process to check for changes in the received ultrasonic waves (e.g., due to changes in the positions of the objects in the space).

[0029] Figure 1B is a diagram of another exemplary load control system 100 ′ having a load control device 110 and a sensor device 120 ′ including only an ultrasonic receiving element. Figure 1A Like the sensor device 120 shown, the sensor device 120' can be mounted to a ceiling or a wall, for example, near (e.g., in the surrounding space) a lighting load 104 controlled by the load control device 110, so that the sensor device 120 can be configured to detect an occupancy condition (e.g., the presence of an occupant) and / or a vacancy condition (e.g., the absence of an occupant) near the lighting load. In response to detecting an occupancy condition and / or a vacancy condition in the space surrounding the lighting load 104, the sensor device 120' can be configured to generate one or more control signals (e.g., analog control signals and / or messages transmitted via a wired or wireless communication link) to which the load control device 110 can respond (e.g., turn on the lighting load 104 in response to receiving an indication of an occupancy condition, and turn off the lighting load 104 in response to receiving an indication of a vacancy condition).

[0030] Figure 1B The load control system 100' shown may also include one or more ultrasonic transmitting devices 130 (e.g., Figure 1B The ultrasonic transmitting device 130 may include an ultrasonic transmitting element (not shown) and a housing 132 having an opening 134 that allows ultrasonic waves 108 to be emitted from the ultrasonic transmitting device 130. The ultrasonic waves 108 may be emitted by the sensor device 120 at an ultrasonic transmitting frequency f US (e.g., about 40 kHz). For example, the ultrasonic transmitting device 130 can be configured to be plugged into an electrical outlet 136 that can have one or more electrical outlets 138. The electrical outlet 136 can be electrically coupled to the AC power source 102 so that the ultrasonic transmitting device 130 can be powered by the electrical outlet 136. Figure 1B Only one ultrasonic emitting device 130 is shown, but the load control system 100' may include additional ultrasonic emitting devices. Examples of load control systems with external ultrasonic emitters are described in more detail in commonly assigned U.S. Patent Application Publication No. 2015 / 0180237, entitled "ULTRASONIC SENSING SYSTEM," published on June 25, 2015, the entire disclosure of which is hereby incorporated herein by reference.

[0031] The sensor device 120' may include occupancy detection circuitry, such as an ultrasonic detection circuit having an ultrasonic receiving element. The sensor device 120' may include a housing 122' having a single opening 126' for allowing ultrasonic waves 108 emitted by a remote ultrasonic transmitter 130 to be received by the ultrasonic receiving element inside the sensor device 120'. The ultrasonic waves 108 emitted by the remote ultrasonic transmitter 130 may be reflected toward the sensor device 120' by objects in the space (e.g., stationary objects and / or moving objects). The ultrasonic waves 108 reflected from the stationary objects may be at an ultrasonic transmission frequency f US (e.g., exhibiting no frequency variation), whereas the ultrasonic wave 108 reflected from the moving object may not be at the ultrasonic wave transmission frequency f US The sensor device 120 may be characterized by a frequency change (e.g., a Doppler shift) that may indicate movement in the space (e.g., may indicate an occupancy condition). The sensor device 120 may be configured to determine whether an occupancy condition and / or a vacancy condition is currently occurring in the space in response to the ultrasonic wave 108 received by the ultrasonic receiving element.

[0032] Although in Figure 1BAlthough not shown, the sensor device 120' may also include another ultrasonic receiving element on the opposite side of the sensor device 120'. The additional ultrasonic receiving element may allow the sensor device 120' to have additional occupancy and / or vacancy detection coverage. The sensor device 120' may be configured to detect occupancy and / or vacancy conditions (e.g., two ultrasonic detection signals, only the first ultrasonic detection signal, or only the second ultrasonic detection signal) using two ultrasonic receiving elements, only the first ultrasonic receiving element, or only the second ultrasonic receiving element. In addition, the sensor device 120' may include a third ultrasonic receiving element or a fourth ultrasonic receiving element and a corresponding opening.

[0033] and Figure 1A Like the sensor device 120 shown, the sensor device 120' can also be configured to operate in a small space mode (e.g., a large signal mode) and a large space mode (e.g., a small signal mode). When in the small space mode, the sensor device 120' can be configured to receive and process ultrasonic waves 108 having a relatively large magnitude (e.g., when the sensor device 120' is installed in a small space). When in the large space mode, the sensor device 120' can be configured to receive and process ultrasonic waves 108 having a relatively small magnitude (e.g., when the sensor device 120' is installed in a large space).

[0034] In some examples, the sensor device 120' may also include additional sensing circuits (e.g., additional occupancy detection circuits) for detecting occupancy and / or vacancy conditions in the space. For example, the sensor device 120' may include an internal PIR detection circuit having a pyroelectric detector, which may be configured to receive infrared energy from an occupant in the space via a lens 129' located on the housing 122'. The sensor device 120' may be configured to detect occupancy and / or vacancy conditions in the space surrounding the lighting load 104 in response to one or both of the ultrasonic detection circuit and the PIR detection. Since the PIR detection circuit may use a different technology from the ultrasonic detection circuit, the dual-technology occupancy sensor may provide an enhanced ability to detect the presence of an occupant in the space surrounding the sensor device 120'. In addition, the additional sensing circuits of the sensor device 120' may also include, for example, a microwave detection circuit, a millimeter wave radar, or any suitable detector or combination of detectors.

[0035] For example, the sensor device 120' may perform a configuration process (e.g., a calibration process) to configure the operation of the sensor device 120', for example, in the space in which the sensor device 120' is installed. For example, during the configuration process, the sensor device 120' may be configured to operate in one of a small space mode and a large space mode during the configuration of the sensor device. In addition, the sensor device 120' may be configured to use two ultrasonic receiving elements or use any one of the ultrasonic receiving elements during the configuration process. For example, the sensor device 120' may be configured to perform the configuration process in response to manual input (e.g., in response to actuation of a button on the sensor device 120') and / or in response to a received message (e.g., transmitted in response to actuation of a button on a remote control and / or a soft button on a display of a mobile device such as a smart phone or tablet). In addition, the sensor device 120' may be configured to automatically perform the configuration process (e.g., as described in more detail below). For example, the sensor device 120' may be configured to perform a configuration process periodically (e.g., once a month) when the space in which the sensor device is located is vacant (e.g., as determined in response to the ultrasonic detection circuit and / or the PIR detection circuit). The configuration process may be an initial configuration process performed when objects in the space are in their expected locations after installation and the space is vacant. In addition, the configuration process may be a maintenance (e.g., recalibration) process performed (e.g., periodically) after the initial execution of the configuration process to check for changes in the received ultrasonic waves (e.g., due to changes in the locations of objects in the space).

[0036] Figure 1C is an exemplary sensing device 150 (e.g., Figure 1A 1 and 1 . A perspective view of a sensor device 120 of a load control 100 is shown. The sensor device 150 may be configured to detect an occupancy condition (e.g., the presence of an occupant) and / or a vacancy condition (e.g., the absence of an occupant) near a lighting load (e.g., lighting load 104). The sensor device 150 may be mounted, for example, to a ceiling or wall near (e.g., the surrounding space) the lighting load, such that the sensor device 150 may be configured to detect an occupancy condition and / or a vacancy condition near the lighting load. The sensor device 150 may be configured to generate one or more control signals in response to detecting an occupancy condition and / or a vacancy condition in the space surrounding the lighting load. For example, the sensor device 150 may be configured to generate an analog control signal and / or transmit a message (e.g., a digital message) (e.g., via a contact closure output circuit) that may be received by a load control device (e.g., load control device 110) for controlling the lighting load in response to the detected occupancy and / or vacancy condition. The sensor device 150 may be battery powered and / or may be connected to an external power source.

[0037] The sensor device 150 may include a housing 152 for housing the circuitry of the sensor device 150. The sensor device 150 may include an occupancy detection circuit (e.g., a first occupancy detection circuit), such as an ultrasonic detection circuit, which includes a pair of ultrasonic elements, such as an ultrasonic transmitting element 153 and / or an ultrasonic receiving element 155, which may be housed in the housing 152. The housing 152 may include a first opening 154 and a second opening 156 in an outer surface 151 of the housing 152. The ultrasonic transmitting element 153 and the ultrasonic receiving element 155 may be positioned behind (e.g., immediately behind) the first opening 154 and the second opening 156, respectively. The first opening 154 may allow ultrasonic waves (e.g., ultrasonic waves 108) to be transmitted from the sensor device 150 through the ultrasonic transmitting element 153, and the second opening 156 may allow ultrasonic waves to be received by the ultrasonic receiving element 155 inside the sensor device 150. The ultrasonic waves may be transmitted by the sensor device 150 at an ultrasonic transmission frequency f US (e.g., approximately 40kHz) transmission.

[0038] The ultrasonic wave emitted by the sensor device 150 may be reflected by an object in the space and returned to the sensor device 150. The emitted ultrasonic wave may be reflected by a stationary object in the space and a moving object in the space. The ultrasonic wave reflected from the stationary object may be reflected by an ultrasonic wave emission frequency f US (e.g., exhibiting no frequency variation). Ultrasonic waves reflected from a moving object may not be transmitted at the ultrasonic frequency f US The sensor device 150 may be characterized by a frequency change (e.g., a Doppler shift) that may indicate movement in the space (e.g., may indicate an occupancy condition). The sensor device 150 may be configured to determine whether an occupancy condition and / or a vacancy condition currently occurs in the space in response to the ultrasonic waves received by the ultrasonic receiving element.

[0039] The size of the first opening 154 can be set and the ultrasonic wave transmitting element 153 can be positioned relative to the first opening 154 to maximize the percentage of ultrasonic waves emitted by the ultrasonic wave transmitting element 153 that leave the housing 152 (e.g., maximize the transmitted power). In addition, the size of the second opening 156 can be set and the ultrasonic wave receiving element 155 can be positioned relative to the second opening 156 to maximize the received power. For example, each of the first opening 154 and the second opening 156 can have a wavelength λ approximately equal to the wavelength of the ultrasonic wave emitted and received by the sensor device 150. USIn addition, each of the first opening 154 and the second opening 156 may have a depth D2 (e.g., between the outer surface 151 of the housing 152 and the ultrasonic transmitting element 153 and the ultrasonic receiving element 155, respectively), which may be equal to the wavelength λ of the ultrasonic wave transmitted and received by the sensor device 150. US The housing 152 of the sensor device 150 may include a respective rib 257 , 258 (eg, a single rib) extending through each of the first opening 154 and the second opening 156 .

[0040] Since the sensor device 150 can be located closer to an object in the space when the sensor device 150 is installed in a small space, the magnitude of the received ultrasonic wave can be relatively large compared to when the sensor device 150 is installed in a large space. When the sensor device 150 is installed in a large space, the magnitude of the received ultrasonic wave may be too small to be processed by the ultrasonic receiving circuit of the sensor device 150. Some existing sensor devices rely on crosstalk between the ultrasonic transmitting element 153 and the ultrasonic receiving element 155 to ensure proper operation in spaces of various sizes. For example, when the ultrasonic wave emitted by the ultrasonic transmitting element 153 is emitted to the ultrasonic receiving element 155 through the housing 152 (e.g., not emitted into the space), crosstalk may occur between the ultrasonic transmitting element 153 and the ultrasonic receiving element 155.

[0041] Since the size of the first opening 154 is set and the ultrasonic emitting element 153 is positioned relative to the first opening 154 to maximize the emission power, the sensor device 150 can be configured to operate in different modes to ensure that the sensor device 150 operates correctly in spaces of various sizes. For example, the sensor device 150 can be configured to operate in a small space mode (e.g., a large signal mode) and a large space mode (e.g., a small signal mode). When in the small space mode, the sensor device 150 can be configured to receive and process ultrasonic waves with relatively large magnitudes (e.g., when the sensor device 150 is installed in a small space). When in the large space mode, the sensor device 150 can be configured to receive and process ultrasonic waves 108 with relatively small magnitudes (e.g., when the sensor device 150 is installed in a large space).

[0042] Although in Figure 1CAlthough not shown, the sensor device 150 may also include a second pair of ultrasonic elements on the opposite side of the sensor device 150 (e.g., another ultrasonic transmitting element and / or ultrasonic receiving element with corresponding openings). The additional ultrasonic transmitting elements and ultrasonic receiving elements may allow the sensor device 150 to have additional occupancy and / or vacancy detection coverage. In addition, for example, when the sensor device 150 is deployed in a load control system having an external ultrasonic transmitter (e.g., with Figure 1B ), the sensor device 150 may include only the ultrasonic receiving element 155 (eg, without the ultrasonic transmitting element 153). In addition, the sensor device 150 may include a third or fourth pair of ultrasonic transmitting elements and ultrasonic receiving elements, and corresponding openings.

[0043] In some examples, the sensor device 150' may also include additional sensing circuits (e.g., additional occupancy detection circuits) for detecting occupancy and / or vacancy conditions in the space. For example, the sensor device 150 may include an internal PIR detection circuit with a pyroelectric detector, which may be configured to receive infrared energy from an occupant in the space via a lens 159 located on the housing 152. The sensor device 150 may be configured to detect occupancy and / or vacancy conditions in the space surrounding the lighting load in response to one or both of the ultrasonic detection circuit and the PIR detection. Since the PIR detection circuit may use a different technology than the ultrasonic detection circuit, the dual-technology occupancy sensor may provide an enhanced ability to detect the presence of an occupant in the space surrounding the sensor device 150. In addition, the additional sensing circuits of the sensor device 150 may also include, for example, microwave detection circuits, millimeter wave radars, or any suitable detector or combination of detectors.

[0044] For example, the sensor device 150' can perform a configuration process (e.g., a calibration process) to configure the operation of the sensor device 150', for example, in the space in which the sensor device 150' is installed. The sensor device 150 may include a cover portion 160 on which a button 162 and a visual indicator 164 may be provided. The sensor device 150 may also include additional buttons (not shown) and additional visual indicators (not shown) that may be accessible when the cover portion 160 is removed from the sensor device 150. During the configuration process, the button 162 and / or the additional buttons under the cover portion 160 may be actuated by a user, and the visual indicator 164 and / or the additional visual indicator under the cover portion 160 may be illuminated by the sensor device 150 to provide feedback. For example, the sensor device 150 may be configured to perform a configuration process in response to actuation of the button 162 and / or the button under the cover portion 160. In addition, the control device 150 can be configured to operate in a small space mode and a large space mode in response to actuation of the button 162 and / or the button under the cover portion 160. In addition, the sensor device 150 can be configured to use two pairs of ultrasonic emitting elements and ultrasonic receiving elements, or one or another pair of ultrasonic emitting elements and ultrasonic receiving elements in response to actuation of the button 162 and / or the button under the cover portion 160. The sensor device 150 can also be configured to perform a configuration process and / or configure the operation of the sensor device 150 in response to one or more messages received from a remote programming device (e.g., a remote control and / or a mobile device). For example, the remote programming device can be configured to transmit a message (e.g., via a radio frequency and / or infrared signal) to the sensor device 150 in response to actuation of one or more buttons of the remote programming device.

[0045] Figure 2A is a block diagram of an exemplary sensor device 200 that may be deployed as Figure 1A The sensor device 120 of the lighting control system 100 shown in FIG. Figure 1B The sensor device 120' and / or Figure 1C The sensor device 150 shown. The sensor device 200 may include an ultrasonic wave transmitting element 202 for transmitting ultrasonic waves (e.g., ultrasonic waves 108) and an ultrasonic wave receiving element 204 for receiving ultrasonic waves. For example, the ultrasonic wave transmitting element 202 may be configured to transmit ultrasonic waves through an opening of a housing of the sensor device 200 (e.g., the first opening 124 of the housing 122), and the ultrasonic wave receiving element 204 may be configured to receive ultrasonic waves through an opening of a housing of the sensor device 200 (e.g., the second opening 126 of the housing 122). For example, both the ultrasonic wave transmitting element 202 and the ultrasonic wave receiving element 204 may include piezoelectric elements.

[0046] The sensor device 200 may include a control circuit 210, which is coupled to the ultrasonic transmitting element 202 via an ultrasonic transmitting circuit 220 to drive the ultrasonic transmitting element 202 to transmit ultrasonic waves. The control circuit 210 may also be coupled to the ultrasonic receiving element 204 via an ultrasonic receiving circuit 230 to receive ultrasonic waves, thereby detecting occupancy and / or vacancy conditions (e.g., the presence and / or absence of an occupant) in the space where the sensor device 200 is installed. For example, the control circuit 210 may include one or more of a processor (e.g., a microprocessor), a microcontroller, a programmable logic device (PLD), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or any suitable controller or processing device.

[0047] The sensor device 200 may include a memory 212 configured to store operating characteristics (e.g., operating settings, control parameters, indications of occupancy and / or vacancy conditions in a space, operating modes of the sensor device, etc.), association information for associating with other devices, and / or instructions for controlling electrical loads. The memory 212 may be implemented as an external integrated circuit (IC) or an internal circuit of the control circuit 210. The memory 212 may include a computer-readable storage medium or a machine-readable storage medium that maintains computer-executable instructions to perform one or more programs and / or functions as described herein. For example, the memory 212 may include computer-executable instructions or machine-readable instructions that, when executed by the control circuit, configure the control circuit to provide one or more parts of the program described herein. The control circuit 210 may access instructions from the memory 212 for execution to cause the control circuit 210 to operate as described herein or to operate one or more other devices as described herein. The memory 212 may include computer-executable instructions for executing configuration software. For example, the operating characteristics and / or associated information stored in memory 212 may be configured during configuration of sensor device 200 .

[0048] The sensor device 200 may include a communication circuit 214 that may allow the control circuit 210 to transmit (e.g., transmit and / or receive) communication signals, such as wired communication signals and / or wireless communication signals (such as radio frequency (RF) signals). The communication circuit 214 may include, for example, an RF transceiver, an RF receiver, an RF transmitter, an infrared (IR) receiver, and / or other suitable wireless communication circuits. For example, the communication circuit 214 may be coupled to an antenna 215 for transmitting and / or receiving RF signals. The sensor device 200 may be configured to communicate messages (e.g., digital messages) with an external control device (e.g., a load control device, such as the load control device 100). For example, the control circuit 210 may be configured to transmit a message to the load control device via the communication circuit 214 when an occupied and / or vacant condition is detected in response to the ultrasonic receiving circuit 230. In addition, the control circuit 210 performs a configuration process and / or adjusts the operating characteristics and / or settings of the sensor device 200 in response to a message received via the communication circuit 214 (e.g., received from a remote control and / or a mobile device).

[0049] Sensor device 200 may include user interface circuitry 216. User interface circuitry 216 may include, for example, one or more actuators (e.g., mechanical tactile switches), which may be buttons (e.g., button 162 and / or Figure 1C The user interface circuit 216 may also include one or more light sources (e.g., light emitting diodes) for illuminating visual indicators (e.g., visual indicators 164 and / or Figure 1C The control circuit 210 may be configured to perform a configuration process and / or adjust an operating characteristic and / or setting of the sensor device 200 in response to actuation of an actuator of the user interface circuit 216, and / or illuminate a visual indicator of the user interface 216 to provide feedback (e.g., during configuration of the sensor device 200).

[0050] The sensor device 200 may include a power supply 218 for generating a power supply voltage V PS , powering the control circuit 210 and other low voltage circuits of the sensor device 200. For example, the power supply 218 may include one or more batteries and / or photovoltaic power sources (e.g., solar cells). In addition, the power supply 218 may include one or more energy storage elements, such as supercapacitors and / or rechargeable batteries. In addition, the power supply 218 may also be configured to receive power from an external power source (such as an external direct current (DC) power source or alternating current (AC) power source). The sensor device 200 may also include a power supply 219, which may be configured to receive a power supply voltage VPS And generate one or more DC power supply voltages. For example, the power supply 219 can be configured to generate a first power supply voltage V CC1 (e.g., about 3.3 volts) for powering the control circuit 210, the memory 212, the communication circuit 214, and / or the user interface circuit 216. In addition, the power supply 219 can be configured to generate a second power supply voltage V CC2 (eg, approximately 10 volts) for powering the ultrasonic transmitting circuit 220 and / or the ultrasonic receiving circuit 230 .

[0051] The ultrasonic transmitting circuit 220 may be configured to drive the ultrasonic transmitting element 202 so that the ultrasonic transmitting element 202 transmits ultrasonic waves that can be transmitted from the sensor device 200. For example, the ultrasonic driving circuit 220 may include a driving circuit for powering the ultrasonic transmitting element 202, such as an H-bridge driving circuit. The control circuit 210 may generate an ultrasonic driving signal V DR The ultrasonic drive signal can be received by the ultrasonic transmitting circuit 220 and used to enable the ultrasonic transmitting circuit 220 to generate an ultrasonic transmitting signal V TX The ultrasonic transmitting circuit 220 can transmit an ultrasonic signal V TX The ultrasonic wave transmitting element 202 is driven to transmit ultrasonic waves. For example, the ultrasonic wave transmitting signal V TX The ultrasonic drive signal V may include a periodic oscillating voltage, such as an alternating current (AC) voltage, a pulse width modulated (PWM) voltage, a square wave voltage, a triangular wave voltage, and / or a sinusoidal voltage. DR Ultrasonic emission frequency f US The ultrasonic transmission signal V is characterized by a frequency of about 40 kHz (eg, about 40 kHz) and a duty cycle of about 50% (eg, or another suitable duty cycle for transmitting ultrasonic waves). TX It can also transmit ultrasonic waves at a frequency of f US The control circuit 210 can control the ultrasonic drive signal V DR The phase Φ DR To control the phase Φ of the transmitted ultrasonic wave TX For example, the control circuit 210 may adjust the phase Φ of the transmitted ultrasonic wave. TX Control is zero.

[0052] The transmitted ultrasonic wave emitted by the ultrasonic wave emitting element 202 may be reflected by objects (eg, stationary objects and moving objects) in the space and returned to the sensor device 200. The ultrasonic wave reflected from the stationary object may be transmitted at the ultrasonic wave emission frequency f US The ultrasonic wave reflected from the moving object may exhibit a frequency change (e.g., a Doppler shift). For example, the ultrasonic wave reflected from the moving object may be Doppler shifted by a frequency fDS (such as about 39.5kHz to 40.0kHz or 40.0kHz to 40.5kHz). The frequency change Δf due to the Doppler shift (for example, Δf=f DS –f US ) may be, for example, about 100 Hz to 500 Hz. The control device 200 receives only non-Doppler shifted reflected waves to indicate a vacant condition in the space, while the control device receives at least some Doppler shifted reflected waves to indicate an occupied condition in the space. Due to the propagation delay of the ultrasonic wave from the reflecting object, both the non-Doppler shifted reflected wave and the Doppler shifted reflected wave may be delayed by a phase of Φ compared to the transmitted ultrasonic wave. PD For example, the phase delay Φ PD It can be the phase Φ of the received ultrasound RX and the phase Φ of the transmitted ultrasonic wave TX The difference between.

[0053] The reflected ultrasonic wave can be received by the ultrasonic wave receiving element 204, and the ultrasonic wave receiving element can generate an ultrasonic wave receiving signal V in response to the received ultrasonic wave. RX (For example, ultrasonic receiving voltage signal). RX It may include a periodic oscillation signal, such as a sinusoidal voltage. The received ultrasonic wave may be the sum of a Doppler shifted reflected wave (e.g., reflected from a moving object) and a non-Doppler shifted reflected wave (e.g., reflected from a stationary object). Therefore, the ultrasonic receiving signal V RX The received signal V without Doppler shift can be NS and Doppler shifted received signal V DS The ultrasonic receiving signal V RX Can be relative to the ultrasonic emission signal V TX With phase delay Φ PD (e.g., between a received ultrasonic wave and a transmitted ultrasonic wave).

[0054] The ultrasonic receiving circuit 230 can receive the ultrasonic receiving signal V RX And generate ultrasonic detection signal V DET For example, the ultrasonic detection signal may indicate the occupied or vacant status of the space where the sensor device 200 is located. The ultrasonic receiving circuit 230 may include an amplifier circuit 240, which may receive and amplify the ultrasonic receiving signal V RX To generate the amplified voltage V AMP The amplifier circuit 240 may be configured to convert the offset voltage V OFF (e.g., DC offset voltage) is added to the ultrasonic receiving signal V RXAmplifier circuit 240 may be characterized by a gain α (eg, about 10). For example, the amplified voltage V AMP It may be a sinusoidal voltage characterized by a DC offset.

[0055] The ultrasonic receiving circuit 230 may further include an envelope detector circuit 250, which may receive the amplified signal V AMP And generate the envelope signal V ENV Envelope detector circuit 250 may include, for example, an amplitude modulation (AM) demodulator circuit. For example, envelope detector circuit 250 may be characterized by a gain β (eg, approximately 2). Envelope signal V ENV The magnitude of the amplified signal V AMP For example, when there is no Doppler shift in the received ultrasound, the envelope signal V ENV The value can be approximately equal to the amplified signal V AMP In addition, when there is a Doppler frequency shift in the received ultrasonic wave, the envelope signal V ENV can be expressed as a frequency f with a DC offset and approximately equal to the frequency change Δf due to the Doppler shift ENV is a characteristic sinusoidal voltage.

[0056] The ultrasonic receiving circuit 230 may further include a filter circuit 260, which may receive the envelope signal V ENV And filter it to generate an ultrasonic detection signal V DET (eg, a filtered signal). Ultrasonic detection signal V DET can be received by the control circuit 210, which can be configured to detect the ultrasonic wave signal V DET The filter circuit 260 may include, for example, a bandpass filter circuit. For example, the filter circuit 260 may be characterized by a bandwidth of approximately 500 Hz. The filter circuit 260 may also operate as an anti-aliasing filter to limit the ultrasonic detection signal V DET The bandwidth of the ultrasonic detection signal V DET The control circuit 210 may appropriately sample the received ultrasonic wave. For example, when there is a Doppler frequency shift in the received ultrasonic wave, the ultrasonic wave detection signal V DET can be expressed as a frequency f approximately equal to the frequency change Δf due to the Doppler shift DET is a characteristic sinusoidal voltage.

[0057] The control circuit 210 may be configured to receive the ultrasonic detection signal V DET , and in response to the ultrasonic detection signal V DETTo detect the occupancy and / or vacancy status of the space in which the sensor device 200 is installed. For example, the control circuit 210 may include an analog-to-digital converter (ADC) for converting the ultrasonic detection signal V DET The control circuit 210 may be configured to: when there is a Doppler frequency shift in the received ultrasonic wave and the ultrasonic wave detection signal V DET The control circuit 210 may be configured to determine that an occupied condition exists when the received ultrasonic wave has no Doppler shift and the ultrasonic wave detection signal V DET When the magnitude of is relatively small (eg, approximately zero volts and / or has only a magnitude due to noise), it is determined that an vacant condition exists. For example, the control circuit 210 may be configured to detect the presence of an ultrasonic detection signal V DET The value is greater than the upper voltage threshold V TH+ (For example, the ultrasonic detection signal V DET about 50% of the maximum value) or less than the lower voltage threshold V TH– (For example, the ultrasonic detection signal V DET The occupancy condition is detected when the ultrasonic detection signal V DET There is a DC offset, so when there is no occupancy in the space, the ultrasonic detection signal V DET The value can be kept at the upper voltage threshold V TH+ and the lower voltage threshold V TH– The upper voltage threshold V TH+ and the lower voltage threshold V TH– It may be a predetermined fixed value and / or may be adjusted by the control circuit 210. In addition, the control circuit 210 may be configured to receive the ultrasonic detection signal V from the filter circuit 270. DET Digital filtering is performed to provide additional filtering before attempting to detect occupied and / or vacant conditions.

[0058] Although in Figure 2A Although not shown in the figure, the sensor device 200 may also include a second pair of ultrasonic elements (e.g., another ultrasonic transmitting element and another ultrasonic receiving element). The control circuit 210 may be configured to generate a second ultrasonic drive signal (e.g., similar to the first ultrasonic drive signal V DR ), the second ultrasonic drive signal may be received by a second ultrasonic transmitting circuit (e.g., may be the same as the ultrasonic transmitting circuit 220) to cause the second ultrasonic transmitting element to transmit ultrasonic waves. For example, the control circuit 210 may be configured to generate (e.g., initially generate) ultrasonic drive signals that are out of phase with each other (e.g., approximately 90° or 180° out of phase with each other). The sensor device 200 may include a second ultrasonic receiving circuit (e.g., may be the same as the ultrasonic transmitting circuit 220) to cause the second ultrasonic transmitting element to transmit ultrasonic waves. Figure 2A The second ultrasonic receiving circuit may be configured to generate a second ultrasonic detection signal (e.g., similar to the first ultrasonic detection signal V generated by the first ultrasonic receiving circuit 230) in response to the ultrasonic wave received by the second ultrasonic receiving element. DET ).

[0059] During the configuration of the sensor device 200, the sensor device 200 may be configured to use two ultrasonic receiving circuits (e.g., both the first ultrasonic receiving circuit 230 and the second ultrasonic receiving circuit) or any one ultrasonic receiving circuit (e.g., the first ultrasonic receiving circuit 230 or the second ultrasonic receiving circuit). When the sensor device 200 is configured to use two ultrasonic receiving circuits, the control circuit 210 may be configured to detect an occupied and / or vacant condition in response to ultrasonic detection signals generated by the two ultrasonic receiving circuits of the sensor device 200. When the sensor device 200 is configured to use the first ultrasonic receiving circuit 230, the control circuit 210 may be configured to stop responding to the second ultrasonic detection signal generated by the second ultrasonic receiving circuit, and respond to the first ultrasonic detection signal V generated by the first ultrasonic receiving circuit 230. DET When the sensor device 200 is configured to use the second ultrasonic receiving circuit, the control circuit 210 may be configured to stop the first ultrasonic detection signal V DET The control circuit is configured to generate two ultrasonic drive signals to cause both ultrasonic transmitting elements to emit ultrasonic waves.

[0060] In some examples, the sensor device 200 may also include additional occupant detection circuits, such as a passive infrared (PIR) detection circuit 290. The PIR detection circuit 290 may include a pyroelectric detector configured to receive infrared energy from an occupant in the space via a lens (e.g., lens 129, 129', 159) of the control device 200. In response to the infrared energy received by the pyroelectric detector, the PIR detection circuit 290 may be configured to generate a PIR detection signal V PIR The PIR detection signal may be received by the control circuit 210 and may indicate an occupied and / or vacant condition in the space. The control circuit 210 may be configured to respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230. DET and the PIR detection signal V generated by the PIR detection circuit 290 PIROne or both of the two can be used to detect occupancy and / or vacancy conditions in a space. Since the PIR detection circuit 290 can use a different technology than the ultrasonic transmission circuit 220 and the ultrasonic reception circuit 230, the dual technology occupancy sensor can provide an enhanced ability to detect the presence of occupants in the space surrounding the sensor device.

[0061] As described above, when the sensor device 200 is installed in a small space, the magnitude of the received ultrasonic wave may be relatively large compared to when the sensor device 200 is installed in a large space. NS The magnitude and / or Doppler shift of the received signal V DS The magnitude of the ultrasonic reception signal V may be greater than the magnitude of those signals when the sensor device 120 is installed in a large space. When the sensor device 200 is installed in a small space, the ultrasonic reception signal V RX The value of the non-Doppler shifted received signal V due to the non-Doppler shifted reflected wave NS and / or the Doppler-shifted received signal V generated by the Doppler-shifted reflected wave DS The combination of the magnitudes of V and V may be large enough so that the circuits of the ultrasonic receiving circuit 230 (e.g., the amplifier circuit 240, the envelope detector circuit 250, and / or the filter circuit 260) can correctly process the ultrasonic receiving signal V RX However, when the sensor device 200 is installed in a large space, the ultrasonic receiving signal V RX The value of may not be large enough, so that the circuit of the ultrasonic receiving circuit 230 cannot correctly process the ultrasonic receiving signal V RX .

[0062] Figure 2B 1 is a block diagram of another exemplary sensor device 200', which can be deployed as the sensor device 120 of the lighting control system 100 shown in FIG. Figure 1B The sensor device 120' and / or Figure 1C The sensor device 150 shown. The sensor device 200' may have Figure 2A The sensor device 200′ may also include a signal generator circuit 270. The signal generator circuit 270 may be configured to generate a supplemental signal V SUP , the supplementary signal may be combined with the ultrasonic receiving signal V before being received by the amplifier circuit 240 RX The supplemental signal V is combined (e.g., added to the ultrasonic receive signal) to ensure that the magnitude of the signal processed by the ultrasonic receive circuit 230 is large enough to be properly processed (e.g., as described in more detail below).SUP The ultrasonic transmission signal V may include a periodic oscillating voltage, such as an AC voltage, a PWM voltage, a square wave voltage, a triangle wave voltage, a sinusoidal voltage and / or a near-sinusoidal signal. TX Ultrasonic detection frequency f US As a feature.

[0063] The control circuit 210' of the sensor device 200' may be configured to generate a signal generating a control signal V CON , the signal generation control signal can be received by the signal generator circuit 270 to control the supplementary signal V SUP For example, the control circuit 210' may be configured to detect the ultrasonic wave at a duty cycle of about 50%. US The signal generates the control signal V CON Pulse width modulation (eg, the signal generator circuit 270 may be configured to receive a signal at an ultrasonic detection frequency f US and a pulse width modulated signal characterized by a duty cycle of approximately 50%). The signal generator circuit 270 may be configured to generate a control signal V in response to the signal CON (eg, a pulse width modulated signal) is generated as a signal at an ultrasonic detection frequency f US A complementary signal V of a characteristic sinusoidal signal (eg, a nearly sinusoidal signal) SUP . Supplementary signal V SUP DC offset and peak-to-peak magnitude V P-P For example, the signal generator circuit 270 may be configured to generate a control signal V for the signal (eg, using a low-pass filter or a band-pass filter). CON Filtering is performed to remove harmonics and generate a complementary signal V as a nearly sinusoidal signal SUP . The supplementary signal V SUP It is added to the ultrasonic reception signal V before being received by the amplifier circuit 240 RX (For example, the input signal V IN It can be the ultrasonic receiving signal V RX and the complementary signal V SUP The sum of the complementary signal V SUP Added to the ultrasonic receiving signal V RX In the case of IN , amplify the signal V AMP and / or envelope signal V ENV ) can be large enough to be processed correctly. SUP The peak-to-peak value V P-P May have a nominal peak-to-peak magnitude of approximately 2 volts.

[0064] The control circuit 210' may be configured to generate a control signal V CON The phase Φ CON The control circuit 210' may be configured to generate a control signal V CON The phase Φ CON With (for example, relative to the ultrasonic drive voltage V DR ) adjusts the supplementary signal V SUP The phase Φ SUP For example, the control circuit 210 may be configured to generate a control signal V for the signal CON Pulse width modulation is performed so that the pulse width modulated signal generated by the control circuit is initially equal to the ultrasonic drive signal V DR In phase (eg, signal generation control signal V CON Can be connected with the ultrasonic drive signal V DR For example, the control circuit 210 can control the ultrasonic drive signal V DR The phase Φ DR The sum signal generates the control signal V CON The phase Φ CON Initially, they are all zero (for example, so that the ultrasonic drive signal V DR The control signal V CON In addition, the control circuit 210' can be configured to be in phase with the ultrasonic drive signal V DR The phase Φ DR Compared with the regulation signal, the control signal V CON The phase Φ CON For example, the control circuit 210' may be configured to convert the supplementary signal V SUP The phase Φ SUP Adjusted to be approximately equal to the phase Φ of the received ultrasonic wave RX (For example, the phase delay Φ PD ).

[0065] The control circuit 210' may be configured to control the signal generator circuit 270 to adjust the supplementary signal V SUP The magnitude, for example, the peak-to-peak magnitude V P-P The control circuit 210' may be configured to generate a magnitude adjustment control signal V MAG-ADJ , the magnitude adjustment control signal can be received by the signal generator circuit 270 to adjust the supplementary signal V SUP The peak-to-peak value V P-P The control circuit 210' may be configured to adjust the value of the control signal V MAG-ADJ The value of (eg, adjusted to about the first power supply voltage V CC1 and / or adjusted to approximately the circuit common terminal) to provide the supplementary signal V SUP The peak-to-peak value VP-P For example, the control circuit 210' can be configured to adjust the supplementary signal V SUP The peak-to-peak value V P-P In some examples, the control circuit 210' can be configured to generate a plurality of magnitude adjustment control signals for adjusting the supplemental signal V SUP The peak-to-peak value V P-P In addition, the control circuit 210' may include a circuit for generating a value adjustment control signal V MAG-ADJ A digital-to-analog converter (DAC) is provided, and may be configured to adjust (eg, continuously adjust) a magnitude adjustment control signal V between two magnitudes (eg, between a nominal peak-to-peak magnitude and approximately zero volts). MAG-ADJ The DC value of.

[0066] and Figure 2A Like the sensor device 200 shown, the sensor device 200' may also include a second pair of ultrasonic elements (e.g., another ultrasonic transmitting element and another ultrasonic receiving element). The sensor device 200' may include a second ultrasonic transmitting circuit for causing the second ultrasonic transmitting element to transmit ultrasonic waves (e.g., the second ultrasonic transmitting circuit may be the same as the ultrasonic transmitting circuit 220), and a second ultrasonic receiving circuit for generating a second ultrasonic detection signal (e.g., the second ultrasonic receiving circuit may be the same as the ultrasonic receiving circuit 230). In addition, the sensor device 200' may include a second signal generating circuit (e.g., the second signal generating circuit may be the same as the signal generator circuit 270) for generating a second supplemental signal, and the second supplemental signal may be added to the second ultrasonic receiving signal (e.g., generated by the second ultrasonic receiving element) before being processed by the second ultrasonic receiving circuit. The control circuit 210 may be configured to generate a second signal generation control signal V CON , used to control the second signal generating circuit to generate a second complementary signal. For example, the second signal generating control signal can be generated by the first signal generating circuit 270 to generate a first signal generating control signal V CON Same, but different phase.

[0067] The control circuit 210' of the sensor device 200' may be configured to perform a configuration process to configure an operating characteristic of the sensor device 210' (e.g., as stored in the memory 212). The control circuit 210' may be configured to configure the same operating characteristic of the sensor device 200' as the control circuit 210 is capable of configuring (e.g., using the configuration process of the sensor device 200 described above). In addition, the control circuit 210 may be configured to configure the operation of the signal generating circuit 270. For example, the control circuit 210' may be configured to perform a configuration process and / or adjust the operation of the signal generating circuit 270 in response to actuation of one or more actuators of the user interface circuit 216 and / or in response to a message received via the communication circuit 214 (e.g., transmitted in response to actuation of a button on a remote control and / or a soft button on a display of a mobile device such as a smart phone or tablet). In addition, the control circuit 210' may be configured to adjust (e.g., automatically adjust) the operation of the signal generating circuit 270 during the configuration process. For example, sensor device 200' may be configured to perform a configuration process periodically (eg, once a month) when the space in which sensor device 200' is located is vacant (eg, as determined in response to ultrasonic receiving circuit 230 and / or PIR detecting circuit 290).

[0068] The control circuit 210' may be configured to adjust the spatial size setting of the sensor device 200' during the configuration process of the sensor device 200'. For example, the sensor device 200' may be configured with one or more spatial size options for the spatial size setting selected during the configuration process of the sensor device 200'. The one or more spatial size options may include, for example, a small spatial option (e.g., a small spatial mode) and a large spatial option (e.g., a large spatial mode). For example, the control circuit 210' may be configured to select one of the spatial size options in response to actuation of one or more actuators of the user interface circuit 216 and / or in response to a message received via the communication circuit 214.

[0069] In addition, the control circuit 210' may be configured to automatically determine to operate in one of the small space mode and the large space mode. For example, the control circuit 210' may be configured to monitor the magnitude of the voltage (e.g., the monitoring voltage) of the ultrasonic receiving circuit 230, which may indicate one or more signals (e.g., the input signal V IN and / or amplify the signal V AMP ) may be at an appropriate value that can be properly processed (eg, to allow the ultrasonic receiving circuit 230 to generate an ultrasonic detection signal V DET ). For example, the envelope signal V ENV The value of the envelope signal V ENVWhen the value of the envelope signal V is large enough, one or more signals of the ultrasonic receiving circuit 230 may be at an appropriate value that can be processed correctly, and when the envelope signal V ENV If the value of is sufficiently small, it may be at a value that may not be processed correctly (e.g., as described in more detail below).

[0070] The control circuit 210′ ​​may respond to the voltage magnitude of the monitoring voltage (eg, in response to the envelope signal V ENV For example, the sensor device 200′ may include a low pass filter (LPF) circuit 292 configured to receive the envelope signal V ENV And generate the filtered envelope signal V ENV-F The low-pass filter circuit 292 may include, for example, a resistor-capacitor (RC) filter circuit. For example, the low-pass filter circuit 292 may be configured to ENV Filtering is performed so that the filtered envelope signal V ENV-F The magnitude of the envelope signal V ENV , and thus also indicates the magnitude of one or more signals (e.g., input signal V IN and / or amplify the signal V AMP ) may be at an appropriate value that can be processed correctly. The control circuit 210′ ​​may include a circuit for controlling the filtered envelope signal V ENV-F In some examples, the control circuit 210' may be configured to receive the envelope signal V ENV And use a digital filter to filter the envelope signal V ENV Filtering is performed (eg, sensor device 200' may not include low pass filter circuit 292).

[0071] The control circuit 210' may be configured to monitor the filtered envelope signal V ENV-F The value of (for example, when the space is vacant) and automatically selects one of the small space mode and the large space mode to operate. For example, when the filtered envelope signal V ENV-F When the value of indicates that one or more signals of the ultrasonic receiving circuit 230 may be at an appropriate value that can be properly processed, the control circuit 210 ′ may determine to operate in the small space mode, and when the filtered envelope signal V ENV-F Operation in the large spatial mode may be determined when the magnitude of indicates that one or more signals of the ultrasonic receiving circuit 230 may not be at an appropriate magnitude to be properly processed.

[0072] When the phase difference between the received ultrasonic wave and the transmitted ultrasonic wave is about 180° (for example, the phase delay between the received ultrasonic wave and the transmitted ultrasonic wave is ΦRD is about 180°) and the ultrasonic receiving signal V RX and the complementary signal V SUP When the values ​​of are approximately equal, the signal V SUP Added to the ultrasonic receiving signal V RX Can cause the input signal V IN The value of V is reduced (eg, about zero volts), so that the ultrasonic receiving circuit 230 may not be able to correctly process the input signal V IN The control circuit 210' may be configured to convert the supplementary signal V SUP The phase Φ SUP Adjust (e.g., automatically adjust) until the ultrasonic receiving circuit can correctly process the input signal V IN For example, the control circuit 210' may be configured to monitor the magnitude of the voltage of the ultrasonic receiving circuit 230 (eg, the envelope signal V ENV and / or the filtered envelope signal V ENV-F ), which indicates that one or more signals of the ultrasonic receiving circuit 230 may be at an appropriate value that can be properly processed. The control circuit 210' may be configured to monitor the filtered envelope signal V ENV-F The value of V (for example, when the space is vacant) and periodically adjusts the supplementary signal V SUP The phase Φ SUP , until the envelope signal V ENV The magnitude of (e.g., as determined by the filtered envelope signal V ENV-F The value of the ultrasonic wave receiving circuit 230 indicates that the signal can be correctly processed to generate the ultrasonic wave detection signal V DET The value of .

[0073] The environmental characteristics of the space where the sensor device 200' is installed may cause the ultrasonic detection signal V DET The value of the noise floor increases. During the configuration process, the control circuit 210' can also be configured to DET The amount of the noise floor is used to adjust (eg, automatically adjust) the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit 210' may be configured to determine the ultrasonic detection signal V DET The magnitude of the noise floor, and in response to the ultrasonic detection signal V DET The noise floor value is used to adjust the supplementary signal V SUP The peak-to-peak value V P-P For example, the detection signal V DET The value of the ultrasonic detection signal V DETThe control circuit 210' may be configured to detect the ultrasonic detection signal V (eg, using an ADC) DET Sampling is performed to determine the ultrasonic detection signal V DET In some examples, the control circuit 210' can detect the ultrasonic signal V DET The samples over time are averaged to determine the ultrasonic detection signal V DET The control circuit 210' may be configured to determine the ultrasonic detection signal V when the space in which the sensor device 200' is installed is vacant (eg, as determined in response to the PIR detection circuit 290). DET The magnitude of the noise floor.

[0074] The control circuit 210' may be configured to respond to the ultrasonic detection signal V DET The value of the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit 210' may be configured to convert the ultrasonic detection signal V DET The value of the noise floor threshold V TH-NF (eg, about 150 mV to 300 mV) for comparison. The control circuit 210' may be configured to DET The value is less than the noise floor threshold V TH-NF The signal V SUP The peak-to-peak value V P-P is set to a first value (eg, a nominal peak-to-peak value), and when the ultrasonic detection signal V DET The magnitude of is greater than (eg, greater than or equal to) the noise floor threshold V TH-NF The signal V SUP The peak-to-peak value V P-P is set to a second magnitude (eg, a reduced peak-to-peak magnitude). In some examples, the control circuit 210' can be configured to set the supplementary signal V SUP The peak-to-peak value V P-P Set to ultrasonic detection signal V DET function of the magnitude of .

[0075] Although the sensor device 200 ′ includes Figure 2B The signal generator circuit 270 shown in FIG. 1 is a circuit diagram of a control circuit 210, but the signal generator circuit 270 may be omitted, and the control circuit 210 may be configured to generate (eg, directly generate) the supplementary signal V SUP For example, the control circuit 210' may include a digital-to-analog converter (DAC) for generating a signal at the ultrasonic detection frequency f USThe control signal V is generated by a characteristic sinusoidal signal CON (For example, the supplementary signal V SUP The control signal V can be generated by the signal generated by the control circuit 210 ′ CON An example of a control circuit that generates a sinusoidal signal using a DAC is described in more detail in commonly assigned U.S. Patent No. 9,155,162, entitled “TWO-WIRE DIMMER WITH IMPROVED ZERO-CROSS DETECTION,” issued on October 6, 2015, the entire disclosure of which is hereby incorporated by reference herein. Those skilled in the art will recognize that other variations are possible.

[0076] Figure 3 is a schematic diagram of an exemplary sensor device 300 (e.g., sensor devices 120, 120', 150, 200, 200'). Sensor device 300 may include an ultrasonic transmitting element 302 (e.g., ultrasonic transmitting element 202) for transmitting ultrasonic waves (e.g., ultrasonic waves 108) and an ultrasonic receiving element 302 (e.g., ultrasonic receiving element 204) for receiving ultrasonic waves. For example, ultrasonic transmitting element 302 and ultrasonic receiving element 304 may each include a piezoelectric element. Ultrasonic transmitting element 302 may respond to an ultrasonic transmitting signal V TX The ultrasonic wave receiving element 304 may generate an ultrasonic wave receiving signal V at the output end 305 in response to the received ultrasonic wave (eg, the reflected ultrasonic wave). RX (eg, a sinusoidal voltage). The output 305 of the ultrasonic receiving element 304 can be coupled to the circuit common terminal via a resistor R306. For example, the ultrasonic receiving signal V RX It can be the non-Doppler shifted received signal V NS (e.g., due to non-Doppler-shifted waves reflected from stationary objects) and Doppler-shifted reflected signals V DS When the sensor device 300 receives Doppler-shifted ultrasonic waves of multiple frequencies, the Doppler-shifted received signal V DS It can be the sum of sinusoidal voltages of multiple frequencies. Ultrasonic receiving signal V RX Can be used with ultrasonic emission signal V TX Compared to the phase delay Φ RX For example, the phase delay Φ PD It can be the phase Φ of the received ultrasound RX The phase Φ of the transmitted ultrasonic wave TX The difference between.

[0077] The sensor device 300 may include a control circuit 310 (eg, the control circuit 210, 210'). The control circuit 310 may generate an ultrasonic drive signal V DR The ultrasonic drive signal can be received by the ultrasonic transmitting circuit 320 (eg, the ultrasonic transmitting circuit 220) so that the ultrasonic transmitting circuit 320 generates an ultrasonic transmitting signal V TX The control circuit 310 may be coupled to the ultrasonic receiving element 304 via the ultrasonic receiving circuit 330 (e.g., the ultrasonic receiving circuit 230) to receive ultrasonic waves, thereby detecting an occupied state and / or a vacant state in the space where the sensor device 300 is installed. For example, the control circuit 310 may include one or more of a processor (e.g., a microprocessor), a microcontroller, a programmable logic device (PLD), a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or any suitable controller or processing device. The control circuit 310 may be powered by a first power supply voltage V CC1 (For example, the first power supply voltage V generated by the power supply 219 CC1 , such as about 3.3 volts). The control circuit 310 may generate an ultrasonic drive signal (eg, Figure 2A and Figure 2B The ultrasonic drive signal V DR ), used to control the ultrasonic transmission signal V received by the ultrasonic transmission element 202 TX Generation of.

[0078] The ultrasonic receiving circuit 330 may include an amplifier circuit 340 (eg, amplifier circuit 240), an envelope detector circuit 350 (eg, envelope detector circuit 250), and a filter circuit 360 (eg, filter circuit 260). The ultrasonic receiving circuit 330 may receive an input signal V IN (For example, the input signal can be combined with the ultrasonic receiving signal V RX Proportional) and generates an ultrasonic detection signal V DET The control circuit 310 can detect the ultrasonic wave signal V DET Sampling is performed to detect occupancy and / or vacancy conditions in response to the received ultrasonic waves.

[0079] The amplifier circuit 340 of the ultrasonic receiving circuit 330 may be configured to receive and amplify the input signal V IN To generate the amplified signal V AMP The amplifier circuit 340 may include an operational amplifier U341 configured to receive an input signal V IN The operational amplifier U341 can be powered by the second power supply voltage V CC2(For example, the second power supply voltage V generated by the power supply 219 CC2 The ultrasonic receiving element 304 may be coupled to the non-inverting input terminal of the operational amplifier U341 of the amplifier circuit 330 via a capacitor C308 (eg, having a capacitance of approximately 470 pF).

[0080] Amplifier circuit 340 may include a first filter circuit including a series combination of a resistor R342 (e.g., having a resistance of about 10 kΩ) and a capacitor C343 (e.g., having a capacitance of about 2.2 nF). The series combination of resistor R342 and capacitor C343 may be coupled between the inverting input of operational amplifier U341 and the circuit common. Amplifier circuit 340 may include a second filter circuit including a parallel combination of a resistor R344 (e.g., having a resistance of about 90.9 kΩ) and a capacitor C345 (e.g., having a capacitance of about 5.6 pF). The parallel combination of resistor R344 and capacitor C345 may be coupled between the inverting input and the output of operational amplifier U341. For example, amplifier circuit 340 is characterized by a gain α of about 10 (e.g., about 20 dB).

[0081] The amplifier circuit 340 can be configured to provide an offset voltage V OFF (e.g., a DC offset voltage) is added to the input voltage V IN The amplifier circuit 340 may include a resistor divider circuit including resistors R346, R347 (eg, each resistor having a resistance of approximately 1 MΩ). The resistor divider circuit may be coupled to the second power supply voltage V CC2 and the circuit common terminal, so that an offset voltage V can be generated at the connection point of resistors R346 and R347 OFF (e.g., having a magnitude of about 5V). Amplifier circuit 340 may include capacitor C348 (e.g., having a capacitance of about 1 μF), which may be coupled between the connection point of resistors R346, R347 and circuit common. OFF The input voltage V IN Can be biased at a bias voltage V OFF For example, the input voltage V IN can be approximately equal to the offset voltage V OFF A DC offset is a characteristic sinusoidal voltage.

[0082] The amplified signal V generated by the amplifier circuit 340 AMP can be equal to the offset voltage VOFF-A The DC offset (e.g., about 5V) is a characteristic sinusoidal voltage. The amplified signal V AMP The value can be high-side voltage V HI and low-side voltage V LO For example, the amplified signal V AMP May have a peak-to-peak magnitude of approximately 2 volts. The amplified signal V AMP High peak voltage V PK-HI The high peak voltage can be a high-side voltage V HI and offset voltage V OFF-A The difference between (for example, V PK-HI =V HI –V OFF-A ). Amplify the signal V AMP Can low peak voltage V PK-LO The low peak voltage can be characterized as an offset voltage V OFF-A and low-side voltage V LO The difference between (for example, V PK-LO =V OFF-A –V LO ). For example, the high peak voltage V PK-HI Can be approximately equal to the low peak voltage V PK-LO .

[0083] The envelope detector circuit 350 may receive the amplified signal V AMP And generate the envelope signal V ENV , the envelope signal can have the characteristics of following the amplified signal V AMP The envelope detector circuit 350 may include, for example, an AM demodulator circuit. For example, the envelope detector circuit 350 may be characterized by a gain β of about 2 (eg, about 6 dB). The envelope signal V ENV The envelope detector circuit 350 may be generated across a parallel combination of a resistor R352 (e.g., having a resistance of approximately 200 kΩ) and a capacitor C354 (e.g., having a capacitance of approximately 2.2 nF). The output of the operational amplifier U341 of the amplifier circuit 330 may be coupled to the parallel combination of the resistor R352 and the capacitor C354 via a series combination of a capacitor C355 (e.g., having a capacitance of approximately 2.2 nF) and a first diode D356. The envelope detector circuit 350 may also include a second diode D358 coupled between the circuit common and a connection point between the capacitor C354 and the first diode D356.

[0084] When the amplified signal V AMP The value is close to the low-end voltage V LO When the capacitor C355 is charged to about the amplified signal V AMP The low peak voltage V PK-LOSubtract the forward voltage drop of the second diode D358. AMP The value is close to the high-end voltage V HI When the voltage at the output of the operational amplifier U341 plus the voltage across the capacitor C355 can be coupled across the parallel combination of the resistor R352 and the capacitor C354. Therefore, the capacitor C354 can be configured to be charged to approximately equal to the high peak voltage V through the first diode D356. PK-HI Plus the low peak voltage V PK-LO Subtract the voltage of the forward voltage drop of the first diode D356 and the second diode D358. PK-HI Can be approximately equal to the low peak voltage V PK-LO , so the envelope signal V ENV The magnitude of (eg, the voltage across the parallel combination of resistor R352 and capacitor C354) may be approximately equal to the high peak voltage V PK-HI In some examples, the envelope detector circuit 340 may not include the capacitor C355 and the second diode D358, and the capacitor C354 may be configured to charge to a high peak voltage V PK-HI The forward voltage drop of the first diode D356 is subtracted (eg, the envelope detector 350 may have a gain of approximately 1).

[0085] When there is no Doppler frequency shift in the received ultrasound, the amplified signal V AMP The high peak voltage V PK-HI and low peak voltage V PK-LO can be substantially constant over time, and the envelope signal V ENV However, when the received ultrasonic wave includes some Doppler-shifted reflected waves (eg, added to the non-Doppler-shifted ultrasonic wave), the amplified signal V AMP The high peak voltage V PK-HI and low peak voltage V PK-LO There will be some low-frequency ripples in the envelope, where the frequency of the low-frequency ripples is approximately equal to the frequency change Δf caused by the Doppler shift. Therefore, the envelope signal V ENV It can be a frequency f that is approximately equal to the frequency change Δf due to Doppler shift (for example, when all Doppler shifted reflections are at a single frequency). ENV When the Doppler shift reflected wave is at multiple frequencies, the envelope signal V ENV It may not be a sinusoidal voltage, but may still be an AC voltage (eg, not a DC voltage).

[0086] The filter circuit 360 can receive and process the envelope signal V ENVFiltering is performed to generate an ultrasonic detection signal V DET (eg, filtering a signal). For example, the filter circuit 360 may include a bandpass filter circuit that may be characterized by a bandwidth of approximately 500 Hz. The filter circuit 360 may also operate as an anti-aliasing filter to limit the ultrasonic detection signal V DET The bandwidth of the ultrasonic detection signal V DET The filter circuit 360 may be configured to convert the ultrasonic detection signal V DET About the reference voltage V REF The reference voltage may be equal to, for example, the first power supply voltage V CC1 about half of (e.g., V REF =V CC1 / 2). For example, when there is a Doppler frequency shift in the received ultrasonic wave, the ultrasonic detection signal V DET The value can be approximately equal to the reference voltage V REF And / or may be characterized by noise (eg, caused by the ultrasonic receiving circuit 330 and / or the control circuit 310). When there is a Doppler frequency shift in the received ultrasonic wave, the ultrasonic detection signal V DET It can be an AC voltage, for example, with a frequency f approximately equal to the frequency change Δf due to the Doppler shift DET is a characteristic sinusoidal voltage.

[0087] When the sensor device 300 is installed in a small space, the received ultrasonic wave may be relatively large, and the ultrasonic wave reception signal V may be relatively large, compared to when the sensor device 300 is installed in a large space. RX The value of can be large enough so that the circuit of the ultrasonic receiving circuit 330 can correctly process the ultrasonic receiving signal V RX For example, the amplified signal V AMP The magnitude (e.g., high peak voltage V PK-HI and / or low peak voltage V PK-LO ) can be greater than the forward voltage drop of diodes D356 and D358, so that an envelope signal V can be generated across capacitor C354. ENV However, when the sensor device 300 is installed in a large space, the amplified signal V AMP The value of may not exceed the forward voltage drop of diodes D356 and D358, so the envelope detector circuit 350 may not be able to generate the envelope signal V ENV .

[0088] The sensor device 300 may include a signal generator circuit 370 (eg, the signal generator circuit 270) that may be configured to generate a signal to be coupled to the ultrasonic receive signal V prior to being received by the amplifier circuit 340. RXCombined with (eg, added to) the complementary signal V SUP . The complementary signal V SUP Added to the ultrasonic receiving signal V RX It can ensure the amplified signal V AMP The magnitude (e.g., high peak voltage V PK-HI and / or low peak voltage V PK-LO ) exceeds the forward voltage drop of diodes D356 and D358, so that the envelope detector circuit 350 can appropriately generate an envelope signal V across capacitor C354. ENV The control circuit 310 may be configured to generate a signal generating a control signal V CON , the signal generation control signal can be received by the signal generator circuit 370 to control the supplementary signal V SUP For example, the control circuit 310 may be configured to detect the ultrasonic wave at a duty cycle of about 50% at the frequency f US Generates control signal V CON The signal generator circuit 370 may include a driver circuit 371 (eg, a level converter circuit including one or more transistors). The driver circuit 371 may receive a signal generation control signal V CON (For example, the value is approximately equal to the first power supply voltage V CC1 The pulse width modulation signal of the magnitude of the second power supply voltage V CC2 The magnitude of the pulse width modulated signal V PWM .

[0089] The pulse width modulated signal V generated by the driving circuit 371 PWM can be received by a two-stage resistor-capacitor (RC) circuit (eg, a filter circuit) for generating a supplementary signal V SUP The signal generator circuit 370 may include a first RC circuit having a resistor R372 (e.g., having a resistance of about 25 kΩ) and a capacitor C373 (e.g., having a capacitance of about 150 pF), and a second RC circuit having a resistor R374 (e.g., having a resistance of about 25 kΩ) and a capacitor C375 (e.g., having a capacitance of about 150 pF). For example, when the drive circuit 361 modulates the pulse width of the signal V PWM The magnitude is towards the second power supply voltage V CC2 When driven high, capacitor C363 can be charged to the second power supply voltage V through resistor R372. CC2 When the driving circuit 371 sends the pulse width modulated signal V PWMWhen the magnitude of is driven low toward circuit common, capacitor C373 can discharge to approximately zero volts through resistor R372. Similarly, capacitor C375 can charge and discharge through resistor R374 in response to the charging and discharging of capacitor C373 to generate a supplementary voltage V across capacitor C375. SUP For example, the complementary signal V SUP It can include ultrasonic detection frequency f US The supplementary signal V is a periodic oscillating voltage characterized by (for example, an AC voltage, a triangular wave voltage and / or an approximately sinusoidal voltage). SUP DC offset and peak-to-peak magnitude V P-P For example, the two-stage RC circuit of the signal generator circuit 370 (eg, including a resistor R372, a capacitor C373, a resistor R374, and a capacitor C375) may be configured to modulate the pulse width of the signal V PWM Filtering is performed to remove harmonics and generate a complementary signal V as a nearly sinusoidal signal SUP .

[0090] Supplementary signal V SUP The non-inverting input terminal of the operational amplifier U341 of the amplifier circuit 340 may be coupled via a series combination of a resistor R376 (e.g., having a resistance of about 175 kΩ) and a capacitor C377 (e.g., having a capacitance of about 470 pF). SUP The ultrasonic receiving signal V can be combined with the ultrasonic receiving signal V before being received by the amplifier circuit 340. RX combined with (eg, added to) the ultrasonic reception signal (eg, the input signal V at the non-inverting input terminal of the operational amplifier U341) IN Can be the ultrasonic receiving signal V RX and the complementary signal V SUP The sum of the complementary signal V SUP Added to the ultrasonic receiving signal V RX In the case of IN , amplify the signal V AMP and / or envelope signal V ENV ) can be large enough to be processed correctly. AMP The high peak voltage V PK-HI and low peak voltage V PK-LO It may be greater than the forward voltage of diodes D356 , D358 of the envelope detector circuit 350 .

[0091] The control circuit 310 may be configured to generate a control signal V CON The phase Φ CONFor example, relative to the ultrasonic drive voltage V DR ) adjusts the supplementary signal V SUP The phase Φ SUP For example, the control circuit 310 may generate (eg, initially generate) a signal generation control signal V CON , so that the pulse width modulated signal V initially generated by the driver circuit 371 of the signal generator circuit 370 PWM With the ultrasonic drive signal V DR For example, the control circuit 310 can generate a control signal V CON The phase Φ CON The control circuit 310 may be configured to be connected to the ultrasonic drive signal V DR Generate (eg, initially generate) the signal generation control signal V in phase CON (For example, the signal generates a control signal V CON The rising and falling edges of the ultrasonic drive signal V DR The rising and falling edges of the signal appear at the same time). When the signal generates the control signal V CON With the ultrasonic drive signal V DR When in phase, the control circuit can make the signal generate the control signal V CON The rising and falling edges of the ultrasonic drive signal V DR In addition, the control circuit 310 can be configured to generate the rising edge and the falling edge of the ultrasonic drive signal V DR The phase Φ DR Compared with the regulation signal, the control signal V CON The phase Φ CON For example, the control circuit 310 may be configured to convert the supplementary signal V SUP The phase Φ SUP Adjusted to be approximately equal to the phase Φ of the received ultrasonic wave RX .

[0092] The control circuit 310 may be configured to control the signal generator circuit 370 to adjust the supplementary signal V SUP The magnitude, for example, the peak-to-peak magnitude V P-P The control circuit 310 may be configured to generate a magnitude adjustment control signal V MAG-ADJ , the magnitude adjustment control signal can be received by the signal generator circuit 370 to adjust the supplementary signal V SUP The peak-to-peak value V P-P For example, the signal generator circuit 370 may include a variable attenuator circuit 380 configured to adjust the impedance in the signal generator circuit 370 to adjust the supplementary signal V SUP The peak-to-peak value V P-PThe variable attenuator circuit 380 may be coupled between a connection point of the first RC circuit and the second RC circuit of the signal generator circuit 370 and a common circuit for adjusting an equivalent impedance of the second RC circuit (eg, as shown in the first RC circuit) to adjust the complementary signal V SUP The peak-to-peak value V P-P . The variable attenuator circuit 380 may include a resistor R382 (e.g., having a resistance of about 4.7 kΩ), a capacitor C384 (e.g., having a capacitance of about 680 pF), and a transistor Q385 (e.g., an NPN bipolar junction transistor). The resistor R382 may be coupled in parallel with the capacitor C384. The parallel combination of the resistor R382 and the capacitor C384 may be coupled in series with the transistor Q385 between a connection point of the first RC circuit and the second RC circuit of the signal generator circuit 370 and a circuit common terminal (e.g., between a connection point of the resistors R372, R374 and the circuit common terminal). The variable attenuator circuit 380 may also include a resistor R386 (e.g., having a resistance of about 20 kΩ) coupled between the base of the transistor Q385 and the control circuit 310, and a resistor R388 (e.g., having a resistance of about 50 kΩ) coupled between the base and the emitter of the transistor Q385.

[0093] The base of transistor Q385 may be configured to receive a magnitude adjustment control signal V from control circuit 310 via resistor R386. MAG-ADJ When the control circuit 310 adjusts the value of the control signal V MAG-ADJ When the magnitude of is driven low (e.g., toward the circuit common terminal), transistor Q385 can be turned off. At this time, the first RC circuit and the second RC circuit of the signal generator circuit 370 (e.g., including resistor R372, capacitor C373, resistor R374 and capacitor C375) can be connected to the pulse width modulated signal V PWM Filtering is performed to generate a complementary signal V SUP (For example, as described above). When the control circuit 310 adjusts the value of the control signal V MAG-ADJ The magnitude (e.g., towards the power supply voltage V CC ) is driven high, transistor Q385 may be turned on, thereby coupling the parallel combination of resistor R382 and capacitor C384 in parallel with capacitor C373 of the first RC circuit of signal generator circuit 370. Resistor R372 of the first RC circuit and resistor R382 of variable attenuator circuit 380 may form a resistor divider circuit, thereby reducing the magnitude of the voltage received by the second RC circuit and also reducing the supplemental signal V SUPCapacitor C384 is operable to maintain substantially the same operation (eg, substantially the same polarity) of signal generator circuit 370 when transistor Q385 is non-conducting and conducting. For example, when transistor Q385 is non-conducting, the supplemental signal V SUP The peak-to-peak value V P-P The peak-to-peak magnitude of the supplementary signal may be about 2 volts, and when the transistor Q385 is turned on, the peak-to-peak magnitude of the supplementary signal may be about 0.7 volts. In some examples, the signal generator circuit 370 may include a plurality of variable attenuator circuits 370, and may be configured to receive a plurality of magnitude adjustment control signals from the control circuit 310 for adjusting the supplementary signal V SUP The peak-to-peak value V P-P Controlled to two or more different values.

[0094] Additionally and / or alternatively, the signal generator circuit 370 may include a circuit for generating a pulse width modulated signal V PWM For example, the integrated circuit may include a timer integrated circuit (e.g., a 555 timer IC), an application specific integrated circuit (IC), a programmable logic device (PLD), a field programmable gate array (FPGA), or a device configured to generate (e.g., continuously generate) a pulse width modulated signal V PWM The control circuit 310 may be configured to generate a signal generating a control signal V CON , used to enable and disable the pulse width modulated signal V PWM The generation of the complementary signal V SUP For example, the control circuit 310 may be configured to generate a control signal V by respectively converting the signal CON The magnitude of the signal driven high and low to enable and disable the supplementary signal V SUP Generation of.

[0095] The sensor device 300 may also include a second pair of ultrasonic elements (e.g., another ultrasonic transmitting element and another ultrasonic receiving element). The sensor device 300 may include a second ultrasonic transmitting circuit (e.g., the second ultrasonic transmitting circuit may be the same as the ultrasonic transmitting circuit 320) for causing the second ultrasonic transmitting element to transmit ultrasonic waves, and a second ultrasonic receiving circuit (e.g., the second ultrasonic receiving circuit may be the same as the ultrasonic receiving circuit 330) for generating a second ultrasonic detection signal. In addition, the sensor device 300 may include a second signal generating circuit (e.g., the second signal generating circuit may be the same as the signal generator circuit 370) for generating a second supplementary signal, which may be added to the second ultrasonic receiving signal (e.g., generated by the second ultrasonic receiving element) before being processed by the second ultrasonic receiving circuit. The control circuit 310 may be configured to generate a second signal generation control signal for controlling the second signal generating circuit to generate the second supplementary signal. For example, the second signal generation control signal may be added to the first signal generation control signal V generated by the first signal generator circuit 370. CON Same, but different phase.

[0096] The control circuit 310 of the sensor device 300 may be configured to perform a configuration process to configure the operating characteristics of the sensor device 310 (e.g., as stored in the memory 212). The control circuit 310 may be configured to configure the operation of the signal generating circuit 370 during the configuration process. For example, the control circuit 310 may be configured to perform the configuration process and / or adjust the operation of the signal generating circuit 370 in response to actuation of one or more of the actuators of the sensor device (e.g., of the user interface circuit 216) and / or in response to a message (e.g., received via the communication circuit 214). In addition, the control circuit 310 may be configured to adjust (e.g., automatically adjust) the operating characteristics of the sensor device 200' during the configuration process. For example, the sensor device 300 may be configured to perform the configuration process periodically (e.g., once a month) when the space where the sensor device 300 is located is vacant (e.g., as determined in response to the ultrasonic receiving circuit 230 and / or the PIR detecting circuit 290).

[0097] The control circuit 310 may be configured to generate the control signal V by, for example, enabling and disabling signals respectively. CON The pulse width modulation and / or regulation signal generates the control signal V CON The magnitude of the signal generating circuit 370 is otherwise enabled and disabled (eg, via an enable pin and / or signal) to enable and disable the signal generating circuit 370 to the complementary signal V SUPFor example, the control circuit 310 may be configured to enable the supplementary signal V when the sensor device 300 is installed in a large space and the received ultrasonic wave may be relatively small (eg, compared to when the sensor device 300 is installed in a small space). SUP The control circuit 310 may also be configured to disable the supplementary signal V when the sensor device 300 is installed in a small space and the received ultrasonic wave may be relatively large (eg, compared to when the sensor device 300 is installed in a large space). SUP For example, the sensor device 300 may be configured with one or more spatial size options, which may be selected during configuration of the sensor device 300 .

[0098] In addition, the control circuit 310 can be configured to automatically determine whether to enable and disable the signal generator circuit 370 for the supplementary signal V SUP For example, the control circuit 310 may be configured to monitor the magnitude of the voltage (eg, monitoring voltage) of the ultrasonic receiving circuit 330, which may indicate one or more signals (eg, input signal V IN and / or amplify the signal V AMP ) may be at an appropriate value that can be properly processed (eg, to allow the ultrasonic receiving circuit 330 to generate an ultrasonic detection signal V DET ). For example, the envelope signal V ENV The value of the envelope signal V ENV When the value of the envelope signal V is large enough, one or more signals of the ultrasonic receiving circuit 330 may be at an appropriate value that can be processed correctly, and when the envelope signal V ENV If the value of is sufficiently small, it may be at a value that may not be processed correctly (e.g., as described in more detail below).

[0099] The control circuit 310 may be configured to respond to the magnitude of the voltage of the monitoring voltage (eg, in response to the envelope signal V ENV The magnitude of the signal generator circuit 370 is used to automatically determine whether to enable or disable the signal generator circuit 370 for the supplementary signal V SUP For example, the control circuit 310 may be configured to receive an envelope signal V ENV A filtered version of the envelope signal V generated by the low pass filter circuit 292 (eg, a filtered envelope signal V generated by the low pass filter circuit 292) ENV-F ), the magnitude of the envelope signal may indicate one or more signals (eg, input signal V IN and / or amplify the signal V AMP ) may be at an appropriate value that can be processed correctly. The control circuit 310 may include an analog-to-digital converter (ADC) for converting the envelope signal V ENVIn some examples, the control circuit 310 may be configured to receive the envelope signal V ENV And use a digital filter to filter the envelope signal V ENV Filtering is performed (eg, sensor device 200' may not include low pass filter circuit 292).

[0100] The control circuit 310 may be configured to detect the envelope signal V generated by the envelope detector circuit 340. ENV The magnitude (e.g., DC magnitude) of the filtered version of the signal is sampled and monitored (e.g., when the space is vacant), and the generation of the supplementary signal V by the signal generator circuit 370 is automatically determined to be enabled or disabled. SUP For example, when the envelope signal V ENV (For example, the envelope signal V ENV When the value of the filtering type) indicates that one or more signals of the ultrasonic receiving circuit 330 may be at an appropriate value that can be properly processed, the control circuit 310 may determine to disable the supplementary signal V SUP The generation of the envelope signal V ENV (For example, the envelope signal V ENV When the value of the filtering type) indicates that one or more signals of the ultrasonic receiving circuit 330 may not be at an appropriate value that can be properly processed, the control circuit may determine to enable the supplementary signal V SUP Generation of.

[0101] When the supplementary signal V SUP is added to the ultrasonic receiving signal V RX The phase difference between the received ultrasonic wave and the transmitted ultrasonic wave is about 180° and the ultrasonic receiving signal V RX and the complementary signal V SUP When the values ​​of are approximately the same, the input signal V IN The value of V may be small (eg, approximately zero volts), so that the ultrasonic receiving circuit 330 may not be able to properly process the input signal V IN The control circuit 310 may be configured to convert the supplementary signal V SUP The phase Φ SUP The ultrasonic receiving circuit 320 is adjusted (eg, automatically adjusted) so that the ultrasonic receiving circuit 320 can correctly process the input signal V IN The control circuit can be configured to determine whether it should respond to the envelope signal V ENV (For example, the envelope signal V ENV The value of the supplementary signal V SUP The phase Φ SUPFor example, the control circuit 310 may include an analog-to-digital converter (ADC) for sampling the envelope detector circuit 350. The control circuit 310 may be configured to measure and store the envelope signal V when the signal generator circuit 370 is disabled. ENV The value of the filtering type (for example, the value may be an indication that the signal of the ultrasonic receiving circuit 330 can be correctly processed to generate the ultrasonic detection signal V DET When the signal generator circuit 370 is enabled, the control circuit 310 can also measure the envelope signal V ENV (For example, the envelope signal V ENV If the envelope signal V when the signal generator circuit 370 is enabled ENV (For example, the envelope signal V ENV The magnitude of the envelope signal V when the signal generator circuit 370 is disabled is approximately equal to ENV (For example, the envelope signal V ENV The control circuit 310 can determine that the phase of the received ultrasonic wave and the transmitted ultrasonic wave is not different by about 180°, and the supplementary signal V SUP The phase Φ SUP .

[0102] If the signal generator circuit 370 is enabled, the envelope signal V ENV The magnitude of the filtered version is less than the envelope signal V when the signal generator circuit 360 is disabled. ENV The control circuit 310 can determine that the phase difference between the received ultrasonic wave and the transmitted ultrasonic wave is about 90°, and can adjust the supplementary signal V SUP The phase Φ SUP For example, the control circuit 310 may periodically adjust (eg, increase and / or decrease) the signal generation control signal V by an adjustment amount ΔΦ. CON The phase Φ CON (For example, thereby adjusting the supplementary signal V SUP The phase Φ SUP ), and then measure the envelope signal V ENV The value of the filtering type is used to determine the envelope signal V ENV Is the magnitude of the new sample of the filtered version of approximately equal to the envelope signal V when the signal generator circuit 370 is disabled? ENV The stored value of the filtered version.

[0103] The control circuit may be configured to respond to the envelope signal V ENV The value of the filtered version determines when to stop regulating the supplementary signal V SUP The phase Φ SUP For example, when the envelope signal VENV The magnitude of the new sample of the filtered version of is approximately equal to the envelope signal V when the signal generator circuit 370 is disabled. ENV When the stored value of the filtered version is reached, the control circuit 310 may stop regulating the signal generation control signal V during normal operation. CON The phase Φ CON , and use the signal to generate the control signal V CON The current phase Φ CON To generate the complementary signal V SUP . Signal generation control signal V CON The final phase Φ CON Can be the envelope signal V ENV The value of the filtered version is in the range indicating that the signal of the ultrasonic receiving circuit 330 can be properly processed to generate the ultrasonic detection signal V DET For example, the control circuit 310 can generate a control signal V CON The final phase Φ CON Stored in memory (e.g., memory 212) for use during normal operation.

[0104] During the configuration process, the control circuit 310 can also be configured to detect the ultrasonic wave according to the signal V DET The amount of the noise floor is used to adjust (eg, automatically adjust) the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit 310 may be configured to determine the ultrasonic detection signal V DET The magnitude of the noise floor, and in response to the ultrasonic detection signal V DET The noise floor value is used to adjust the supplementary signal V SUP The peak-to-peak value V P-P For example, the ultrasonic detection signal V DET The value of the ultrasonic detection signal V DET The control circuit 310 may be configured to detect the ultrasonic detection signal V (eg, using an ADC) DET Sampling is performed to determine the ultrasonic detection signal V DET In some examples, the control circuit 310 can detect the ultrasonic signal V DET The samples over time are averaged to determine the ultrasonic detection signal V DET The control circuit 310 may be configured to determine the ultrasonic detection signal V when the space in which the sensor device 300 is installed is vacant (eg, as determined in response to the PIR detection circuit 290). DET The magnitude of the noise floor.

[0105] The control circuit 310 may be configured to respond to the ultrasonic detection signal V DET The value of the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit 310 may be configured to convert the ultrasonic detection signal V DET The value of the noise floor threshold V TH-NF (eg, about 150 mV to 300 mV) for comparison. The control circuit 310 may be configured to DET The value is less than the noise floor threshold V TH-NF The signal V SUP The peak-to-peak value V P-P is set to a first value (eg, a nominal peak-to-peak value), and when the ultrasonic detection signal V DET The magnitude of is greater than (eg, greater than or equal to) the noise floor threshold V TH-NF The signal V SUP The peak-to-peak value V P-P The control circuit 310 may be configured to adjust the control signal V MAG-ADJ The magnitude of the complementary signal V SUP The peak-to-peak value V P-P The control circuit 310 may be configured to adjust the control signal V by adjusting the magnitude of the control signal V MAG-ADJ The magnitude is towards the first power supply voltage V CC1 is driven high to turn off transistor Q385, thereby compensating the signal V SUP The peak-to-peak value V P-P Controlled to a second magnitude (eg, a reduced peak-to-peak magnitude).

[0106] Figure 4 4 is a flow chart of an exemplary process 400 for detecting occupancy and / or vacancy conditions in a space by installing a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300). For example, process 400 can be performed by a control circuit of the sensor device (e.g., control circuit 210, 210', 310). For example, at 410, the control process can be performed periodically (e.g., approximately once every 2 milliseconds). The control circuit can be configured to receive an ultrasonic detection signal V generated by an ultrasonic receiving circuit (e.g., ultrasonic receiving circuit 230, 330). DET The ultrasonic receiving circuit may be configured to generate an ultrasonic detection signal V in response to ultrasonic waves received by the sensor device. DET, so that the ultrasonic detection signal V DET The occupancy and / or vacancy status in the space may be indicated.

[0107] At 412, the control circuit may be configured to detect the ultrasonic wave signal V DET Sampling is performed to generate a sample S D At 414, the control circuit may be configured to D For example, the control circuit can remove the DC component from the sample S at 414. D Subtract the reference value S from REF For example, the reference value S REF It can be equal to the filter circuit 350 for the ultrasonic detection signal V DET The reference voltage V for biasing REF (For example, approximately equal to the first power supply voltage V CC1 In addition, the control circuit can be configured to measure and store the reference value S, for example during a calibration process of the sensor device. REF At 416, the control circuit may be configured to determine the sample S D The absolute value S ABS (For example, S ABS =|S D |). If at step 416 the absolute value S ABS Greater than or equal to the detection threshold S TH-DET , the control circuit can determine at step 418 that the space is occupied (e.g., detect an occupancy condition), and process 400 can end. ABS Less than the detection threshold S TH-DET , the control circuit can determine that the space is vacant (e.g., a vacant condition is detected) at step 420, and then the process 400 ends.

[0108] Figure 5Flowchart of an exemplary process 500 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 500 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 500 to determine an operating mode of the sensor device. For example, the sensor device may be configured to operate in a small space mode (e.g., a large signal mode) and a large space mode (e.g., a small signal mode). When in the small space mode, the sensor device may be configured to receive and process ultrasonic waves having a relatively large magnitude (e.g., when the sensor device is installed in a small space). When in the large space mode, the sensor device may be configured to receive and process ultrasonic waves having a relatively small magnitude (e.g., when the sensor device is installed in a large space). For example, the control process may be performed periodically in response to detecting actuation of an actuator and / or in response to receiving a message at 510 (e.g., via an RF signal).

[0109] At 512, the control circuit may receive an indication of an operating mode of the sensor device. The control circuit may be configured to determine to operate in one of the small space mode and the large space mode in response to actuation of one or more actuators (e.g., actuators of the user interface circuit 216) and / or in response to a message received by the communication circuit (e.g., the communication circuit 214). When the large space mode is indicated at 514, the control circuit may enable the supplemental signal V in the sensor device at 516 before the process 500 ends. SUP For example, the complementary signal V SUP The ultrasonic receiving signal V generated by the ultrasonic receiving element (e.g., the ultrasonic receiving element 204, 304) may be added to the ultrasonic receiving signal V generated by the ultrasonic receiving element (e.g., the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (e.g., the ultrasonic receiving circuit 230, 330). RX . The complementary signal V SUP Added to the ultrasonic receiving signal V RX It can be ensured that the magnitude of the signal processed by the ultrasonic receiving circuit is large enough to be processed correctly when the sensor device is installed in a large space. The control circuit can be configured to generate a signal generating control signal V CON , the signal generation control signal can be received by the signal generator circuit (eg, signal generator circuit 270, 360) to control the supplementary signal V SUP For example, the control circuit can be configured to generate a control signal V by CON Pulse width modulation is used to enable the complementary signal V SUP When the large space mode is not indicated at 514 (eg, the small space mode is indicated), the control circuit may disable the supplementary signal V at 518.SUP The generation of the control signal V can be stopped, and the process 500 can end. For example, the control circuit can be configured to generate the control signal V CON Pulse width modulation is performed to disable the supplementary signal V SUP Generation of.

[0110] Figure 6 6 is a flow chart of an exemplary process 600 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 600 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 600 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 302) to transmit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUP The supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX Combined with (eg, added to) the ultrasonic reception signal. The control circuit may be configured to generate a signal generating a control signal V CON (For example, pulse width modulation is performed), and the signal generation control signal can be received by the signal generator circuit to control the supplementary signal V SUP The control circuit can perform process 600 to enable and / or disable the supplementary signal V SUP The generation of the ultrasonic receiving circuit can ensure that the ultrasonic receiving signal V RX (For example, the ultrasonic receiving signal V RX and the complementary signal V SUP of ).

[0111] The control circuit may be configured to perform process 600 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 600 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 610 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 600 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit. The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 600 is performed (e.g., for each ultrasonic receiving circuit).

[0112] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 612, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 600 may simply exit. At 614, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 600 is executed at 610, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 600 can exit. WAIT When the space within the length is vacant, the control circuit can continue to 616 to configure the operation of the signal generator circuit.

[0113] At 616, the control circuit may generate an ultrasonic drive signal V DR The ultrasonic drive signal V DR can be received by the ultrasonic transmitting circuit, which can generate an ultrasonic transmitting voltage V TX . Ultrasonic emission voltage V TX The ultrasonic wave transmitting element can receive the ultrasonic wave. For example, the control circuit can be configured to receive the ultrasonic wave driving signal. VDR Pulse width modulation is performed so that the ultrasonic drive signal VDR To transmit ultrasonic frequency fUS (e.g., about 40 kHz) and a PWM voltage characterized by a duty cycle of about 50%. The control circuit can control the ultrasonic drive signal V DR The phase Φ DRTo control the phase Φ of the transmitted ultrasonic wave TX For example, the control circuit can change the phase Φ of the emitted ultrasonic wave TX If the sensor device does not include an ultrasonic transmitting element and an ultrasonic transmitting circuit (for example, the sensor device is used in a load control system with an external ultrasonic transmitter), the ultrasonic drive signal V at 612 in process 600 can be omitted. DR Generation of.

[0114] At 618, the control circuit can be configured to disable the supplemental signal V SUP For example, the control circuit may be configured to generate the control signal V by stopping the signal CON Pulse width modulation and / or drive to generate control signal V CON The magnitude of V is used to otherwise disable the signal generator circuit, disabling the supplemental signal V at 618. SUP At 620, the control circuit may be configured to sample a magnitude (e.g., a DC magnitude) of a voltage (e.g., a monitoring voltage) of the ultrasonic receiving circuit, which may indicate that one or more signals of the ultrasonic receiving circuit may be at an appropriate magnitude that can be properly processed (e.g., to allow the ultrasonic receiving circuit to generate an ultrasonic detection signal V DET ). For example, the monitoring voltage can be the envelope signal V ENV and / or envelope signal V ENV Filtered version (e.g., the filtered envelope signal V ENV-F The control circuit may be configured to monitor the magnitude (eg, DC magnitude) of the voltage (eg, envelope signal V ENV The magnitude and / or envelope of the signal V ENV The filtering type) is sampled and stored to generate samples S MON .

[0115] At 622, the control circuit can be configured to determine the magnitude of the monitoring voltage (eg, from the sample S MON Indicates the envelope signal V ENV The magnitude and / or envelope of the signal V ENV The control circuit may be configured to determine whether the sample S indicates that one or more signals of the ultrasonic receiving circuit have an appropriate magnitude that can be properly processed. MON With threshold S TH-MON For comparison, and when the sample S MON The value exceeds the threshold S TH-MON When the control circuit determines at 622 that the magnitude of the monitoring voltage is at an appropriate level, process 600 may exit (eg, disable the supplemental signal V SUPof generation).

[0116] When the control circuit determines at 622 that the magnitude of the monitoring voltage is not at an appropriate level, the control circuit can be configured to enable the supplemental signal V at 624 before the process 600 exits. SUP For example, the control circuit can be configured to generate a control signal V by CON Pulse width modulation and / or drive to generate control signal V CON The signal generator circuit is enabled by the magnitude of , and the supplementary signal V is enabled at 620 SUP At 624, the control circuit can retrieve a signal generation control signal V from, for example, a memory (eg, memory 212). CON The phase Φ CON When the process 600 is performed for the first time (eg, as part of an initial configuration process of the sensor device), the control circuit may be configured to generate the control signal V CON The phase Φ CON Initialized to zero (eg, so that the signal generates a control signal V CON The phase Φ CON Equal to the ultrasonic drive signal V DR The phase Φ DR When process 600 is subsequently performed (eg, after an initial configuration process of the sensor device), the control circuit may be configured to phase Φ during a previous execution of process 600. CON Without being modified, the signal generates the control signal V CON The phase Φ CON is determined to be zero, or during a previous execution of process 600 the phase Φ CON When the signal generation control signal V is modified, the phase of the signal generation control signal is determined to be another value. CON The phase Φ CON is zero (for example, the signal generates a control signal V CON With the ultrasonic drive signal V DR In phase), the control circuit can make the signal generate a control signal V CON The rising and falling edges of the ultrasonic drive signal V DR The rising and falling edges are generated simultaneously.

[0117] Figure 77 is a flow chart of an exemplary process 700 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 700 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 700 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 302) to emit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUP The supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX Combined with (eg, added to) the ultrasonic reception signal. The control circuit may be configured to generate a signal generating a control signal V CON (For example, pulse width modulation is performed), and the signal generation control signal can be received by the signal generator circuit to control the supplementary signal V SUP For example, the complementary signal V SUP The received ultrasonic wave may be generated in phase with the transmitted ultrasonic wave (eg, initially generated). The received ultrasonic wave may be delayed in phase with the transmitted ultrasonic wave ΦRX When the received ultrasonic wave is out of phase with the transmitted ultrasonic wave (for example, the phase difference is about 180°) and the ultrasonic receiving signal V RX and the complementary signal V SUP has approximately the same magnitude, will complement the signal V SUP Added to the ultrasonic receiving signal V RX The control circuit may perform process 700 to convert the supplementary signal V SUP The phase Φ SUP Adjust until the ultrasonic receiving circuit can process the ultrasonic receiving signal V RX and the complementary signal V SUP The value of the combination.

[0118] The control circuit may be configured to perform process 700 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 700 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 710 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 700 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit. The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 700 is performed (e.g., for each ultrasonic receiving circuit).

[0119] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 712, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 700 may simply exit. At 714, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 700 is executed at 710, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 700 can exit. WAIT When the space within the length is vacant, the control circuit can continue to 716 to configure the operation of the signal generator circuit.

[0120] At 716, the control circuit may generate an ultrasonic drive signal V DR The ultrasonic drive signal V DR can be received by the ultrasonic transmitting circuit, which can generate an ultrasonic transmitting voltage V TX . Ultrasonic emission voltage V TX The ultrasonic wave transmitting element can receive the ultrasonic wave. For example, the control circuit can be configured to receive the ultrasonic wave driving signal. VDR Pulse width modulation is performed so that the ultrasonic drive signal VDR To transmit ultrasonic frequency fUS (e.g., about 40 kHz) and a PWM voltage characterized by a duty cycle of about 50%. The control circuit can control the ultrasonic drive signal V DR The phase Φ DRTo control the phase Φ of the transmitted ultrasonic wave TX For example, the control circuit can change the phase Φ of the emitted ultrasonic wave TX If the sensor device does not include an ultrasonic transmitting element and an ultrasonic transmitting circuit (for example, the sensor device is used in a load control system with an external ultrasonic transmitter), the ultrasonic drive signal V at 712 in process 700 can be omitted. DR Generation of.

[0121] At 718, the control circuit can be configured to enable the supplemental signal V SUP For example, the control circuit can be configured to generate a control signal V by CON Pulse width modulation and / or drive to generate control signal V CON The signal generator circuit is enabled by the magnitude of , and the supplementary signal V is enabled at 718 SUP At 718, the control circuit can retrieve a signal generation control signal V from, for example, a memory (eg, memory 212). CON The phase Φ CON When performing process 700 for the first time (eg, as part of an initial configuration process of the sensor device), the control circuit may be configured to generate a control signal V CON The phase Φ CON Initialized to zero (eg, so that the signal generates a control signal V CON The phase Φ CON Equal to the ultrasonic drive signal V DR The phase Φ DR When process 700 is subsequently performed (eg, after an initial configuration process of the sensor device), the control circuit may be configured to phase Φ during a previous execution of process 700. CON Without being modified, the signal generates the control signal V CON The phase Φ CON is determined to be zero, or during a previous execution of process 700 the phase Φ CON When the signal generation control signal V is modified, the phase of the signal generation control signal is determined to be another value. CON The phase Φ CON is zero (for example, the signal generates a control signal V CON With the ultrasonic drive signal V DR In phase), the control circuit can make the signal generate a control signal V CON The rising and falling edges of the ultrasonic drive signal V DR The rising and falling edges are generated simultaneously.

[0122] At 720, the control circuit may be configured to sample a magnitude (e.g., a DC magnitude) of a voltage (e.g., a monitoring voltage) of the ultrasonic receiving circuit, which may indicate that one or more signals of the ultrasonic receiving circuit may be at an appropriate magnitude that can be properly processed (e.g., to allow the ultrasonic receiving circuit to generate an ultrasonic detection signal V DET ). For example, the monitoring voltage can be the envelope signal V ENV and / or envelope signal V ENV Filtered version (e.g., the filtered envelope signal V ENV-F For example, the control circuit may be configured to monitor the voltage (eg, the envelope signal V ENV and / or envelope signal V ENV The magnitude (e.g., DC magnitude) of the sample (filtered version) is sampled and stored to generate a sample S MON .

[0123] At 722, the control circuit may be configured to determine the magnitude of the monitoring voltage (eg, as determined by the sample S MON The control circuit may be configured to determine whether the sample S indicates that one or more signals of the ultrasonic receiving circuit have an appropriate magnitude that can be properly processed. MON With threshold S TH-MON For comparison, and when the sample S MON The value exceeds the threshold S TH-MON When the value of the monitoring voltage is determined to be at an appropriate level. SUP Added to the ultrasonic receiving signal V RX Does not cause the input signal V IN With a smaller magnitude (eg, monitoring voltage sample S MON Exceeding the threshold S TH-MON ), the control circuit can determine when generating the supplementary signal V SUP The voltage value is monitored to determine whether it is at an appropriate level, and the signal generation control signal V may be stored at 724 before the process 700 ends. CON The phase Φ CON For example, when the process is performed for the first time, sample S MON When the control circuit is at an appropriate level at 724, the control circuit can generate the control signal V CON The phase Φ CON Stored as initial phase.

[0124] When the received ultrasonic wave at 722 is out of phase with the transmitted ultrasonic wave and the supplementary signal V SUP Added to the ultrasonic receiving signal V RX So that the input signal V IN With a smaller magnitude (e.g., sample SMON Less than the threshold S TH-MON ), the control circuit may determine that the magnitude of the monitoring voltage is not at an appropriate level, and may generate a control signal V at 726. CON The phase Φ CON The magnitude of the monitoring voltage is sampled at 720 to generate another sample S MON , and at 722, determine the sample S MON For example, the adjustment amount ΔΦ may be a fixed amount, so that the control circuit generates a control signal V at 726 each time the adjustment signal is generated. CON The phase Φ CON When the signal is adjusted by the same amount, the control signal V CON The phase Φ CON In addition, the adjustment amount ΔΦ may be the amount of adjustment that is generated whenever the control circuit adjusts the signal at 726 to generate the control signal V CON The phase Φ CON For example, the control circuit may use an interval dichotomy method (eg, a binary search method) to adjust the signal generation control signal V CON The phase Φ CON For example, at 726, the first adjustment signal generates a control signal V CON The phase Φ CON When the control circuit can generate the control signal V CON The phase Φ CON Adjust to about 180° (for example, with the ultrasonic drive signal V DR The phase Φ DR Then, at 726, each adjustment signal generates a control signal V CON The phase Φ CON When the signal generates the control signal V CON The phase Φ CON Adjust to approximately equal the phase Φ CON The control circuit may continue to generate the control signal V at 726. CON The phase Φ CON The voltage is adjusted by the adjustment amount ΔΦ, and the value of the monitoring voltage is sampled at 720 until the sample S is at 722. MON At 724, the control circuit may then generate a control signal V before the process 700 ends. CON The phase Φ CON Stored as the phase last set at 726 .

[0125] Figure 88 is a flow chart of an exemplary process 800 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 800 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 800 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 304) to emit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUP The supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX Combined with (eg, added to) the ultrasonic reception signal. The control circuit may be configured to generate a signal generating a control signal V CON (For example, pulse width modulation is performed), and the signal generation control signal can be received by the signal generator circuit to control the supplementary signal V SUP For example, the complementary signal V SUP The received ultrasonic wave may be generated in phase with the transmitted ultrasonic wave (eg, initially generated). The received ultrasonic wave may be delayed in phase with the transmitted ultrasonic wave ΦRX When the received ultrasonic wave is out of phase with the transmitted ultrasonic wave (for example, the phase difference is about 180°) and the ultrasonic receiving signal V RX and the complementary signal V SUP has approximately the same magnitude, will complement the signal V SUP Added to the ultrasonic receiving signal V RX This may result in a signal having a small magnitude (eg, approximately zero volts), which may not be processed by the ultrasonic receiving circuit. The control circuit may perform process 800 to enable and / or disable the supplemental signal V SUP The generation of the complementary signal V SUP The phase Φ SUP Adjust until the ultrasonic receiving circuit can process the ultrasonic receiving signal V RX and the complementary signal V SUP The value of the combination.

[0126] The control circuit may be configured to perform process 800 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 800 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 810 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 800 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit. The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 800 is performed (e.g., for each ultrasonic receiving circuit).

[0127] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 812, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 800 may simply exit. At 814, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 800 is executed at 810, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 800 can exit. WAIT When the space within the length is vacant, the control circuit can continue to 816 to configure the operation of the signal generator circuit.

[0128] At 816, the control circuit may generate an ultrasonic drive signal V DR The ultrasonic drive signal V DR can be received by the ultrasonic transmitting circuit, which can generate an ultrasonic transmitting voltage V TX . Ultrasonic emission voltage V TX The ultrasonic wave transmitting element can receive the ultrasonic wave. For example, the control circuit can be configured to receive the ultrasonic wave driving signal. VDR Pulse width modulation is performed so that the ultrasonic drive signal VDR To transmit ultrasonic frequency fUS (e.g., about 40 kHz) and a PWM voltage characterized by a duty cycle of about 50%. The control circuit can control the ultrasonic drive signal V DR The phase Φ DRTo control the phase Φ of the transmitted ultrasonic wave TX For example, the control circuit can change the phase Φ of the emitted ultrasonic wave TX If the sensor device does not include an ultrasonic transmitting element and an ultrasonic transmitting circuit (for example, the sensor device is used in a load control system with an external ultrasonic transmitter), the ultrasonic drive signal V at 812 in process 800 can be omitted. DR Generation of.

[0129] At 818, the control circuit may be configured to disable the supplemental signal V SUP For example, the control circuit may be configured to generate the control signal V by stopping the signal CON Pulse width modulation and / or drive to generate control signal V CON The magnitude of V is used to otherwise disable the signal generator circuit, disabling the supplemental signal V at 818. SUP At 820, the control circuit may be configured to sample a magnitude (e.g., a DC magnitude) of a voltage (e.g., a monitoring voltage) of the ultrasonic receiving circuit, which may indicate that one or more signals of the ultrasonic receiving circuit may be at an appropriate magnitude that can be properly processed (e.g., to allow the ultrasonic receiving circuit to generate an ultrasonic detection signal V DET ). For example, the monitored voltage can be an envelope signal VENV and / or envelope signal VENV Filtered version (e.g., filtered envelope signal VENV-F The control circuit may be configured to monitor the voltage (eg, the envelope signal V ENV and / or envelope signal V ENV The magnitude (e.g., DC magnitude) of the sample (filtered version) is sampled and stored to generate a sample S MON .

[0130] At 822, the control circuit can be configured to determine the magnitude of the monitoring voltage (eg, as determined by the sample S MON The control circuit may be configured to determine whether the sample S indicates that one or more signals of the ultrasonic receiving circuit have an appropriate magnitude that can be properly processed. MON With threshold S TH-MON For comparison, and when the sample S MON The value exceeds the threshold S TH-MON When the control circuit determines at 822 that the magnitude of the monitoring voltage is at an appropriate level, process 800 may exit (eg, disable the supplemental signal V SUP of generation).

[0131] When the control circuit determines at 822 that the magnitude of the monitoring voltage is not at an appropriate level, the control circuit may be configured to enable the supplemental signal V at 824. SUP For example, the control circuit can be configured to generate a control signal V by CON Pulse width modulation and / or drive to generate control signal V CON The signal generator circuit is enabled by the magnitude of , and the supplementary signal V is enabled at 820 SUP At 824, the control circuit may retrieve a signal generation control signal V from, for example, a memory (eg, memory 212). CON The phase Φ CON When the process 800 is performed for the first time (eg, as part of an initial configuration process of the sensor device), the control circuit may be configured to generate the control signal V CON The phase Φ CON Initialized to zero (eg, so that the signal generates a control signal V CON The phase Φ CON Equal to the ultrasonic drive signal V DR The phase Φ DR When process 800 is subsequently performed (eg, after an initial configuration process of the sensor device), the control circuit may be configured to phase Φ during a previous execution of process 800. CON Without being modified, the signal generates the control signal V CON The phase Φ CON is determined to be zero, or during a previous execution of process 800 the phase Φ CON When the signal generation control signal V is modified, the phase of the signal generation control signal is determined to be another value. CON The phase Φ CON is zero (for example, the signal generates a control signal V CON With the ultrasonic drive signal V DR In phase), the control circuit can make the signal generate a control signal V CON The rising and falling edges of the ultrasonic drive signal V DR The rising and falling edges are generated simultaneously.

[0132] At 826, the control circuit may be configured to sample the magnitude of the voltage of the ultrasonic receiving circuit (e.g., the magnitude of the monitoring voltage indicating that one or more signals of the ultrasonic receiving circuit may be at a magnitude that can be properly processed) to enable the supplemental signal V SUP Generate sample S in the case of generation MON At 828, the control circuit can be configured to determine the magnitude of the monitoring voltage (eg, as a sample S MON indicates whether the supplementary signal VSUP When the sample S is generated, one or more signals of the ultrasonic receiving circuit are at an appropriate value that can be processed correctly. For example, the control circuit can be configured to MON With threshold S TH-MON When the sample value exceeds the threshold S TH-MON When the value of the monitoring voltage is determined to be at an appropriate level. SUP Added to the ultrasonic receiving signal V RX Does not cause the input signal V IN With a smaller magnitude (eg, monitoring voltage sample S MON Exceeding the threshold S TH-MON ), the control circuit can determine when generating the supplementary signal V SUP The voltage value is monitored to determine whether it is at an appropriate level, and the signal generation control signal V may be stored at 830 before the process 800 ends. CON The phase Φ CON For example, when the process is performed for the first time, sample S MON When the signal at 828 is at an appropriate level, the control circuit can generate the control signal V CON The phase Φ CON Stored as initial phase.

[0133] When the received ultrasonic wave at 828 is out of phase with the transmitted ultrasonic wave and the supplementary signal V SUP Added to the ultrasonic receiving signal V RX So that the input signal V IN With a smaller magnitude (e.g., sample S MON Less than the threshold S TH-MON ), the control circuit may determine that the magnitude of the monitoring voltage is not at an appropriate level, and may generate a control signal V at 830. CON The phase Φ CON The magnitude of the monitored voltage is sampled at 826 to generate another sample S MON , and at 828, determine the sample S MON For example, the adjustment amount ΔΦ may be a fixed amount, so that at 830 the control circuit generates a control signal V each time the adjustment signal is CON The phase Φ CON When the signal is adjusted by the same amount, the control signal V CON The phase Φ CON In addition, the adjustment amount ΔΦ may be the amount of adjustment that is generated whenever the control circuit adjusts the signal at 830 to generate the control signal V CON The phase Φ CONFor example, the control circuit may use an interval dichotomy method (eg, a binary search method) to adjust the signal generation control signal V CON The phase Φ CON For example, at 830, the first adjustment signal generates a control signal V CON The phase Φ CON When the control circuit can generate the control signal V CON The phase Φ CON Adjust to about 180° (for example, with the ultrasonic drive signal V DR The phase Φ DR Then, at 830, each adjustment signal generates a control signal V CON The phase Φ CON When the signal generates the control signal V CON The phase Φ CON Adjust to approximately equal the phase Φ CON The control circuit may continue to generate the control signal V at 830. CON The phase Φ CON The voltage is adjusted by the adjustment amount ΔΦ, and the magnitude of the monitoring voltage is sampled at 826 until the sample S at 828 MON At 832, the control circuit may then generate a control signal V before the process 800 ends. CON The phase Φ CON Stored as the phase last set at 830 .

[0134] Fig. 9 900 is a flow chart of an exemplary process 900 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 900 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 900 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 302) to transmit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUPThe supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX The control circuit may be configured to generate a magnitude adjustment control signal V MAG-ADJ The magnitude adjustment control signal can be received by the signal generator circuit to adjust the supplementary signal V SUP The peak-to-peak value V P-P The control circuit may execute process 900 to respond to an ultrasonic detection signal V received from an ultrasonic receiving circuit. DET The noise floor value is used to adjust the supplementary signal V SUP The peak-to-peak value V P-P .

[0135] The control circuit may be configured to perform process 900 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 900 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 910 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 900 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit (e.g., for independently adjusting the complementary signal V of the two ultrasonic receiving circuits). SUP The peak-to-peak value V P-P ). The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 900 is executed (eg, for each ultrasonic receiving circuit).

[0136] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 912, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 900 may simply exit. At 914, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 900 is executed at 910, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 900 can end.WAIT When the space within the length of is vacant, the control circuit can determine whether to enable the supplementary signal V at 916. SUP If the supplementary signal V is not enabled at 916 SUP If the generation of the supplementary signal V is enabled at 916, the process 900 can end. SUP If a signal is generated, the control circuit can continue to 918 to configure the operation of the signal generator circuit.

[0137] At 918, the control circuit can determine the ultrasonic detection signal V DET For example, when the space is vacant, the ultrasonic detection signal V DET The value of the ultrasonic detection signal V DET The control circuit can be configured to detect the ultrasonic detection signal V at 918. DET Sampling is performed to generate sample S NF (For example, it can indicate that the ultrasonic detection signal V DET The magnitude of the noise floor).

[0138] At 920, before the process 900 ends, the control circuit may detect the ultrasonic wave based on the signal V DET Sample S NF To adjust the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit can be configured to convert the ultrasonic detection signal V DET Sample S NF With threshold S TH-NF For comparison, and when the sample S NF Less than the threshold S TH-NF The signal V SUP The peak-to-peak value V P-P is set to a first magnitude (eg, a nominal peak-to-peak magnitude), and when the sample S NF Greater than (eg, greater than or equal to) a threshold value S TH-NF The peak-to-peak magnitude of the supplemental signal is set to a second magnitude (eg, a reduced peak-to-peak magnitude) when the control circuit is configured to adjust the magnitude control signal V MAG-ADJ The magnitude of the signal is driven low toward the circuit common terminal to compensating the signal V SUP The peak-to-peak value V P-P to a first magnitude (eg, a nominal peak-to-peak magnitude), and the magnitude adjustment control signal V MAG-ADJ The magnitude is towards the first power supply voltage V CC1 Drive high to complement the signal V SUP The peak-to-peak value V P-PIn some examples, the control circuit can be configured to generate a plurality of magnitude adjustment control signals at 920 for adjusting the supplemental signal V SUP The peak-to-peak value V P-P Additionally or alternatively, the control circuit may be configured to adjust the ultrasonic detection signal V DET Sample S NF To adjust the supplementary signal V SUP The peak-to-peak value V P-P For example, the control circuit may include a circuit for generating a magnitude adjustment control signal V MAG-ADJ A digital-to-analog converter (DAC) is provided, and may be configured to adjust (eg, continuously adjust) a magnitude adjustment control signal V between two magnitudes (eg, between a nominal peak-to-peak magnitude and approximately zero volts). MAG-ADJ For example, the control circuit may be configured to adjust the control signal V according to the magnitude (eg, DC magnitude). MAG-ADJ The value and ultrasonic detection signal V DET The linear relationship between the values ​​of the ultrasonic detection signal V DET Sample S NF To adjust the value of the control signal V MAG-ADJ The value of .

[0139] Fig.10 1 is a flow chart of an exemplary process 1000 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 1000 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 1000 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 302) to transmit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUP The supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX The control circuit may be configured to generate a magnitude adjustment control signal VMAG-ADJ The magnitude adjustment control signal can be received by the signal generator circuit to adjust the supplementary signal V SUP The peak-to-peak value V P-P The control circuit can execute process 1000 to convert the supplementary signal V SUP The peak-to-peak value V P-P Adjust to a first magnitude (eg, a nominal peak-to-peak magnitude) or a second magnitude (eg, a reduced peak-to-peak magnitude).

[0140] The control circuit may be configured to perform process 1000 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 1000 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 1010 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 1000 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit (e.g., for independently adjusting the complementary signal V of the two ultrasonic receiving circuits). SUP The peak-to-peak value V P-P ). The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 1000 is executed (eg, for each ultrasonic receiving circuit).

[0141] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 1012, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 1000 may simply exit. At 1014, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 1000 is executed at 1010, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 1000 can end. WAIT When the space within the length of is vacant, the control circuit can determine whether to enable the supplementary signal V at 1016. SUP If the supplementary signal V is not enabled at 1016 SUP If the complementary signal V is enabled at 1016, the process 1000 may end. SUPIf a signal is generated, the control circuit can continue to 1018 to configure the operation of the signal generator circuit.

[0142] At 1018, the control circuit can detect the ultrasonic signal V DET Sampling is performed to generate sample S NF To determine the ultrasonic detection signal V DET For example, when the space is vacant, the ultrasonic detection signal V DET The value of the ultrasonic detection signal V DET The magnitude of the noise floor (e.g., such a sample S NF Can indicate ultrasonic detection signal V DET The magnitude of the noise floor).

[0143] At 1020, the control circuit can determine the ultrasonic detection signal V DET Sample S NF Is it greater than or equal to the threshold S? TH-NF For example, at 1020, the control circuit may DET Sample S NF With threshold S TH-NF When the ultrasonic detection signal V at 1020 DET Sample S NF Less than the threshold S TH-NF , before the process 1000 ends, the control circuit may at 1022 set the supplementary signal V SUP The peak-to-peak value V P-P is set to a first magnitude (eg, a nominal peak-to-peak magnitude). For example, the control circuit may be configured to adjust the magnitude of the control signal V MAG-ADJ The magnitude of is driven low toward the circuit common terminal to make the complementary signal V SUP The peak-to-peak value V P-P When the ultrasonic detection signal V at 1020 DET Sample S NF Greater than or equal to the threshold S TH-NF , before the process 1000 ends, the control circuit may at 1024 set the supplementary signal V SUP The peak-to-peak value V P-P is set to a second magnitude (eg, a reduced peak-to-peak magnitude). For example, the control circuit may be configured to adjust the magnitude of the control signal V MAG-ADJ The magnitude is towards the first power supply voltage V CC1 Drive high to add the complementary signal V at 1024 SUP The peak-to-peak value V P-P Adjust to the second value.

[0144] Fig.11 1 is a flow chart of an exemplary process 1100 for configuring a sensor device (e.g., sensor device 120, 120', 150, 200, 200', 300) to enable detection of occupancy and / or vacancy conditions in a space. For example, process 1100 may be performed by a control circuit (e.g., control circuit 210', 310) of the sensor device. The control circuit may perform process 800 to calibrate the operation of the sensor device. The control circuit may be configured to cause the sensor device to emit ultrasonic waves and detect occupancy and / or vacancy conditions in the space in response to the ultrasonic waves reflected from objects in the space and received by the sensor device. The sensor device may control an ultrasonic wave transmitting circuit (e.g., ultrasonic wave transmitting circuit 220, 320) to cause an ultrasonic wave transmitting element (e.g., ultrasonic wave transmitting element 202, 302) to emit ultrasonic waves. The sensor device may include a signal generator circuit (e.g., signal generator circuit 270, 370), which may be configured to generate a supplemental signal V SUP The supplementary signal is combined with the ultrasonic receiving signal V generated by the ultrasonic receiving element (for example, the ultrasonic receiving element 204, 304) before being processed by the ultrasonic receiving circuit (for example, the ultrasonic receiving circuit 230, 330). RX Combined with (eg, added to) the ultrasonic reception signal. The control circuit may be configured to generate a signal generating a control signal V CON (For example, pulse width modulation is performed), and the signal generation control signal can be received by the signal generator circuit to control the supplementary signal V SUP For example, the complementary signal V SUP The received ultrasonic wave may be generated in phase with the transmitted ultrasonic wave (eg, initially generated). The received ultrasonic wave may be delayed in phase with the transmitted ultrasonic wave ΦRX When the received ultrasonic wave is out of phase with the transmitted ultrasonic wave (for example, the phase difference is about 180°) and the ultrasonic receiving signal V RX and the complementary signal V SUP has approximately the same magnitude, will complement the signal V SUP Added to the ultrasonic receiving signal V RX This may result in a signal having a small magnitude (eg, approximately zero volts), which may not be processed by the ultrasonic receiving circuit. The control circuit may perform process 1100 to enable and / or disable the supplemental signal V SUP The generation of the complementary signal V SUP The phase Φ SUP Adjust until the ultrasonic receiving circuit can process the ultrasonic receiving signal V RX and the complementary signal V SUP The control circuit can be configured to generate a magnitude adjustment control signal VMAG-ADJ The magnitude adjustment control signal can be received by the signal generator circuit to adjust the supplementary signal V SUP The peak-to-peak value V P-P The control circuit can also perform process 1100 to convert the supplementary signal V SUP The peak-to-peak value V P-P Adjust to a first magnitude (eg, a nominal peak-to-peak magnitude) or a second magnitude (eg, a reduced peak-to-peak magnitude).

[0145] The control circuit may be configured to perform process 1100 during an initial configuration process of the sensor device and / or during one or more maintenance configuration processes (e.g., after the initial configuration process). For example, the control process 1100 may be performed periodically (e.g., once a month) in response to detecting actuation of the actuator and / or in response to receiving a message at 1110 (e.g., via an RF signal). For example, when the sensor device has two pairs of ultrasonic transmitting elements and ultrasonic receiving elements, the control circuit may perform the control process 1100 separately for each of the corresponding ultrasonic receiving circuit and the corresponding signal generator circuit. The control circuit may control the ultrasonic transmitting circuit so that the two ultrasonic transmitting elements transmit ultrasonic waves each time the control process 1100 is performed (e.g., for each ultrasonic receiving circuit).

[0146] The control circuit may be configured to calibrate the operation of the sensor device when the space is vacant. At 1112, the control circuit may be configured to, for example, respond to the ultrasonic detection signal V generated by the ultrasonic receiving circuit 230, 330. DET and / or the PIR detection signal V generated by the PIR detection circuit 290 PIR To determine whether the space is vacant. If the space is not vacant (eg, occupied), process 1100 may simply exit. At 1114, the control circuit may determine a wait time T WAIT (e.g., about 15 minutes) has expired. For example, when the process 1100 is executed at 1110, the waiting time T WAIT You can start. If you wait for time T WAIT If there is no empty space within the length of , process 800 can exit. WAIT When the space within the length is vacant, the control circuit can continue to 1116 to configure the operation of the signal generator circuit.

[0147] At 1116, the control circuit may generate an ultrasonic drive signal V DR The ultrasonic drive signal V DR can be received by the ultrasonic transmitting circuit, which can generate an ultrasonic transmitting voltage V TX. Ultrasonic emission voltage V TX The ultrasonic wave transmitting element can receive the ultrasonic wave. For example, the control circuit can be configured to receive the ultrasonic wave driving signal. VDR Pulse width modulation is performed so that the ultrasonic drive signal VDR To transmit ultrasonic frequency fUS (e.g., about 40 kHz) and a PWM voltage characterized by a duty cycle of about 50%. The control circuit can control the ultrasonic drive signal V DR The phase Φ DR To control the phase Φ of the transmitted ultrasonic wave TX For example, the control circuit can change the phase Φ of the emitted ultrasonic wave TX If the sensor device does not include an ultrasonic transmitting element and an ultrasonic transmitting circuit (for example, the sensor device is used in a load control system with an external ultrasonic transmitter), the ultrasonic drive signal V at 1112 in process 1100 can be omitted. DR Generation of.

[0148] At 1118, the control circuit can be configured to disable the supplemental signal V SUP For example, the control circuit may be configured to generate the control signal V by stopping the signal CON Pulse width modulation and / or drive to generate control signal V CON The magnitude of the signal generator circuit is otherwise disabled, and the supplemental signal V is disabled at 118. SUP At 1120, the control circuit may be configured to sample a magnitude (e.g., a DC magnitude) of a voltage (e.g., a monitoring voltage) of the ultrasonic receiving circuit, which may indicate that one or more signals of the ultrasonic receiving circuit may be at an appropriate magnitude to be properly processed (e.g., to allow the ultrasonic receiving circuit to generate an ultrasonic detection signal V DET ). For example, the monitored voltage can be an envelope signal VENV and / or envelope signal VENV Filtered version (e.g., filtered envelope signal VENV-F The control circuit may be configured to monitor the voltage (eg, the envelope signal V ENV and / or envelope signal V ENV The magnitude (e.g., DC magnitude) of the sample (filtered version) is sampled and stored to generate a sample S MON .

[0149] At 1122, the control circuit can be configured to determine the magnitude of the monitoring voltage (eg, as determined by the sample S MONThe control circuit may be configured to determine whether the sample S indicates that one or more signals of the ultrasonic receiving circuit have an appropriate magnitude to be properly processed. MON With threshold S TH-MON For comparison, and when the sample S MON The value exceeds the threshold S TH-MON When the control circuit determines at 1122 that the magnitude of the monitoring voltage is at an appropriate level, process 1100 may exit (eg, disable the supplemental signal V SUP of generation).

[0150] When the control circuit determines at 1122 that the magnitude of the monitoring voltage is not at an appropriate level, the control circuit may be configured to enable the supplemental signal V at 1124. SUP For example, the control circuit can be configured to generate a control signal V by CON Pulse width modulation and / or drive to generate control signal V CON The signal generator circuit is enabled by the magnitude of , and the supplementary signal V is enabled at 1120 SUP At 1124, the control circuit can retrieve a signal generation control signal V from, for example, a memory (eg, memory 212). CON The phase Φ CON When the process 1100 is performed for the first time (eg, as part of an initial configuration process of the sensor device), the control circuit may be configured to generate the control signal V CON The phase Φ CON Initialized to zero (eg, so that the signal generates a control signal V CON The phase Φ CON Equal to the ultrasonic drive signal V DR The phase Φ DR When process 1100 is subsequently performed (eg, after an initial configuration process of the sensor device), the control circuit may be configured to phase Φ during a previous execution of process 800. CON Without being modified, the signal generates the control signal V CON The phase Φ CON is determined to be zero, or during a previous execution of process 800 the phase Φ CON When the signal generation control signal V is modified, the phase of the signal generation control signal is determined to be another value. CON The phase Φ CON is zero (for example, the signal generates a control signal V CON With the ultrasonic drive signal V DR In phase), the control circuit can make the signal generate a control signal V CON The rising and falling edges of the ultrasonic drive signal VDR The rising and falling edges are generated simultaneously.

[0151] At 1126, the control circuit may be configured to sample the magnitude of the voltage of the ultrasonic receiving circuit (e.g., the magnitude of the monitoring voltage indicating that one or more signals of the ultrasonic receiving circuit may be at a magnitude to be properly processed) to enable the supplemental signal V SUP Generate sample S in the case of generation MON At 1128, the control circuit can be configured to determine the magnitude of the monitoring voltage (eg, as a sample S MON indicates whether the supplementary signal V SUP When the sample S is generated, one or more signals of the ultrasonic receiving circuit are at an appropriate value to be properly processed. For example, the control circuit can be configured to MON With threshold S TH-MON When the sample value exceeds the threshold S TH-MON When the value of the monitoring voltage is determined to be at an appropriate level. SUP Added to the ultrasonic receiving signal V RX Does not cause the input signal V IN With a smaller magnitude (for example, the envelope signal S MON Sample S MON Exceeding the threshold S TH-MON ), the control circuit can determine when generating the supplementary signal V SUP The voltage value is monitored to determine whether it is at an appropriate level, and the signal generation control signal V may be stored at 1130 before the process 1100 ends. CON The phase Φ CON For example, when the process is performed for the first time, sample S MON When the signal at 1128 is at an appropriate level, the control circuit can generate the control signal V CON The phase Φ CON Stored as initial phase.

[0152] When the received ultrasonic wave at 828 is out of phase with the transmitted ultrasonic wave and the supplementary signal V SUP Added to the ultrasonic receiving signal V RX So that the input signal V IN With a smaller magnitude (e.g., sample S MON Less than the threshold S TH-MON ), the control circuit may determine that the magnitude of the monitoring voltage is not at an appropriate level, and may generate a control signal V at 1130 CON The phase Φ CONThe magnitude of the monitored voltage is sampled at 1126 to generate another sample S MON , and at 1128, determine the sample S MON For example, the adjustment amount ΔΦ may be a fixed amount, so that at 1130 the control circuit generates a control signal V each time the adjustment signal CON The phase Φ CON When the signal is adjusted by the same amount, the control signal V CON The phase Φ CON In addition, the adjustment amount ΔΦ may be the amount of adjustment that is generated whenever the control circuit adjusts the signal at 1130 to generate the control signal V CON The phase Φ CON For example, the control circuit may use an interval dichotomy method (eg, a binary search method) to adjust the signal generation control signal V CON The phase Φ CON For example, at 1130, the first adjustment signal generates a control signal V CON The phase Φ CON When the control circuit can generate the control signal V CON The phase Φ CON Adjust to about 180° (for example, with the ultrasonic drive signal V DR The phase Φ DR Then at 1130, each time the adjustment signal generates a control signal V CON The phase Φ CON When the signal generates the control signal V CON The phase Φ CON Adjust to approximately equal the phase Φ CON The control circuit may continue to generate the control signal V at 1130. CON The phase Φ CON The voltage is adjusted by the adjustment amount ΔΦ, and the magnitude of the monitoring voltage is sampled at 1126 until the sample S at 1128 MON At 1132, the control circuit may then generate a control signal V before the process 1100 ends. CON The phase Φ CON Stored as the phase last set at 1130 .

[0153] At 1134, the control circuit can detect the ultrasonic signal V DET Sampling is performed to generate sample S NF To determine the ultrasonic detection signal V DET For example, when the space is vacant, the ultrasonic detection signal VDET It can have an ultrasonic detection signal V DET The magnitude of the noise floor of the sample S NF Can indicate ultrasonic detection signal V DET At 1136, the control circuit can determine the ultrasonic detection signal V DET Sample S NF Is it greater than or equal to the threshold S? TH-NF For example, at 1136, the control circuit may DET Sample S NF With threshold S TH-NF When the ultrasonic detection signal V at 1136 is DET Sample S NF Less than the threshold S TH-NF , before the process 1100 ends, the control circuit may at 1138 set the supplementary signal V SUP The peak-to-peak value V P-P is set to a first magnitude (eg, a nominal peak-to-peak magnitude). For example, the control circuit may be configured to adjust the magnitude of the control signal V MAG-ADJ The magnitude of is driven low toward the circuit common terminal to drive the complementary signal V SUP The peak-to-peak value V P-P When the ultrasonic detection signal V at 1136 is DET Sample S NF Greater than or equal to the threshold S TH-NF , before the process 1100 ends, the control circuit may at 1140 set the supplementary signal V SUP The peak-to-peak value V P-P is set to a second magnitude (eg, a reduced peak-to-peak magnitude). For example, the control circuit may be configured to adjust the magnitude of the control signal V MAG-ADJ The magnitude is towards the first power supply voltage V CC1 Driven high to complement the signal V at 1140 SUP The peak-to-peak value V P-P Adjust to the second value.

Claims

1. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; a control circuit configured to control generation of a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; an ultrasonic receiving circuit configured to receive a combination of the ultrasonic receiving voltage signal and the supplemental signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied; as well as A control circuit is configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal.

2. The sensor device according to claim 1, further comprising: a signal generator circuit configured to generate the supplemental signal; The control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplementary signal. 3 . The sensor device of claim 2 , wherein the control circuit is configured to control the signal generation control signal to enable and disable the signal generator circuit.

4. The sensor device of claim 3, wherein the control circuit is configured to: pulse width modulating the signal generation control signal at the ultrasonic frequency when the signal generator circuit is enabled; and receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

5. The sensor device of claim 4 , wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled, and determine to adjust a phase of the signal generating control signal when the magnitude of the monitoring voltage is less than a threshold value. 6 . The sensor device of claim 5 , wherein the control circuit is configured to adjust the phase of the supplemental signal until the magnitude of the monitored voltage is greater than the threshold value.

7. The sensor device of claim 4 , wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and the control circuit is further configured to enable the signal generating circuit when the magnitude of the monitoring voltage is less than a threshold value, and to disable the signal generating circuit when the magnitude of the monitoring voltage is greater than the threshold value.

8. The sensor device of claim 4 , wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

9. The sensor device according to claim 4, wherein the ultrasonic receiving circuit comprises: an amplifier circuit configured to amplify the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; an envelope detector circuit configured to receive the amplified signal and generate an envelope signal; as well as a filter circuit configured to filter the envelope signal to generate the detection signal; Wherein the monitoring voltage is a filtered version of the envelope signal.

10. The sensor device of claim 2, wherein the signal generator circuit is configured to generate the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal, and the control circuit is configured to adjust a peak-to-peak magnitude of the supplemental signal in response to a noise floor of the detection signal generated by the ultrasonic receiving circuit.

11. A sensor device as described in claim 10, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplementary signal to a first magnitude when the magnitude of the noise floor of the detection signal is less than a threshold value, and to adjust the peak-to-peak magnitude of the supplementary signal to a second magnitude when the magnitude of the noise floor of the detection signal is greater than the threshold value, wherein the second magnitude is less than the first magnitude. 12 . The sensor device of claim 10 , wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal based on a magnitude of the noise floor of the detection signal.

13. The sensor device of claim 10, wherein the control circuit is configured to automatically adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

14. The sensor device of claim 10, wherein the control circuit is configured to determine the noise floor of the detection signal in response to a magnitude of the detection signal.

15. The sensor device according to claim 1, wherein the ultrasonic wave receiving element comprises a first ultrasonic wave receiving element configured to generate a first ultrasonic wave receiving voltage signal, the signal generator circuit comprises a first signal generator circuit, and the ultrasonic wave receiving circuit comprises a first ultrasonic wave receiving circuit configured to generate a first detection signal; and The sensor device further comprises: a second ultrasonic wave receiving element configured to receive an ultrasonic wave characterized by the ultrasonic wave frequency and generate a second ultrasonic wave receiving voltage signal; a second signal generator circuit configured to generate a second supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; as well as a second ultrasonic receiving circuit configured to receive a combination of the second ultrasonic receiving voltage signal and the second supplemental signal, the second ultrasonic receiving circuit configured to generate a second detection signal indicating when the space is occupied; The control circuit is further configured to receive the second detection signal, and detect an occupancy condition in the space in response to both the first detection signal and the second detection signal, in response to only the first detection signal, or in response to only the second detection signal.

16. A sensor device as described in claim 15, wherein the control circuit is configured to determine whether to respond to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal in response to at least one of actuation of an actuator of the sensor device or a message received by the sensor device.

17. The sensor device of claim 1, wherein the control circuit is configured to automatically configure operation of the signal generating circuit when the space is vacant.

18. The sensor device of claim 17, further comprising: passive infrared detection circuitry including a pyroelectric detector configured to receive infrared energy from an occupant in the space; Wherein the control circuit is configured to automatically configure the operation of the signal generation circuit when the control circuit has determined, in response to the passive infrared detection circuit, that the space is vacant.

19. The sensor device of claim 1, further comprising: A housing, the housing being used to accommodate the ultrasonic receiving element, the signal generator circuit, the ultrasonic receiving circuit and the control circuit; The housing includes an opening in a front surface of the housing, the ultrasonic wave receiving element is configured to receive the ultrasonic wave through the opening, a diameter of the opening is approximately equal to a wavelength of the ultrasonic wave, and a depth between the front surface of the housing and the ultrasonic wave receiving element is approximately equal to one quarter of the wavelength of the ultrasonic wave.

20. The sensor device of claim 1, wherein the control circuit is configured to directly generate the supplemental signal.

21. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; a signal generator circuit configured to generate a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; an ultrasonic receiving circuit configured to receive a combination of the ultrasonic receiving voltage signal and the supplemental signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied; as well as A control circuit is configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal.

22. The sensor device of claim 21, wherein the control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplemental signal.

23. The sensor device of claim 22, wherein the control circuit is configured to control the signal generation control signal to enable and disable the signal generator circuit.

24. The sensor device of claim 23, further comprising: an ultrasonic wave transmitting element, wherein the ultrasonic wave transmitting element is configured to transmit ultrasonic waves; as well as an ultrasonic wave transmitting circuit, wherein the ultrasonic wave transmitting circuit is configured to drive the ultrasonic wave transmitting element so that the ultrasonic wave transmitting element transmits the ultrasonic wave; The control circuit is configured to generate an ultrasonic wave driving signal, and the ultrasonic wave driving signal is received by the ultrasonic wave transmitting circuit to control the ultrasonic wave transmitting element to transmit the ultrasonic wave.

25. The sensor device of claim 24, wherein the ultrasonic wave received by the ultrasonic wave receiving element is characterized by a phase delay compared to the ultrasonic wave transmitted by the ultrasonic wave transmitting element.

26. The sensor device of claim 25, wherein the control circuit is configured to pulse width modulate the signal generation control signal at the ultrasonic frequency and adjust the phase of the signal generation control signal compared to the ultrasonic drive signal to adjust the phase of the supplemental signal.

27. The sensor device of claim 26, wherein the control circuit is configured to receive a monitoring voltage from the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

28. The sensor device of claim 27, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

29. The sensor device of claim 28, wherein the control circuit is configured to periodically perform a configuration process to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

30. The sensor device of claim 28, wherein the control circuit is configured to control the ultrasonic wave transmitting circuit to cause the ultrasonic wave transmitting element to transmit the ultrasonic wave, and at the same time configure an operation of the signal generating circuit in response to the monitoring voltage.

31. The sensor device of claim 27, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to enable the signal generating circuit when the magnitude of the monitoring voltage is less than a threshold value.

32. The sensor device of claim 27, wherein the control circuit is configured to: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled; determining to adjust the phase of the signal generation control signal when the magnitude of the monitored voltage is less than a threshold; as well as The phase of the supplemental signal is adjusted until the magnitude of the monitored voltage is greater than the threshold.

33. The sensor device of claim 23, wherein the control circuit is configured to pulse width modulate the signal generation control signal at the ultrasonic frequency.

34. The sensor device of claim 33, wherein the control circuit is configured to receive a monitoring voltage from the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

35. The sensor device of claim 34, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

36. The sensor device of claim 35, wherein the control circuit is configured to periodically perform a configuration process to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

37. The sensor device of claim 34, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to enable the signal generating circuit when the magnitude of the monitoring voltage is less than a threshold value.

38. The sensor device of claim 37, wherein the control circuit is configured to disable the signal generating circuit when the magnitude of the monitoring voltage is greater than the threshold.

39. The sensor device of claim 34, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled, and to determine to adjust a phase of the signal generating control signal when the magnitude of the monitoring voltage is less than a threshold value.

40. The sensor device of claim 39, wherein the control circuit is configured to adjust the phase of the supplemental signal until the magnitude of the monitored voltage is greater than the threshold.

41. The sensor device of claim 33, wherein the control circuit is configured to adjust the phase of the supplemental signal when the control circuit determines that the supplemental signal is out of phase with the received ultrasonic wave.

42. The sensor device of claim 41, wherein the control circuit is configured to adjust the phase of the supplemental signal until the control circuit determines that the supplemental signal is not out of phase with the received ultrasonic wave.

43. The sensor device of claim 23, wherein the control circuit is configured to enable the signal generator circuit to generate the supplemental signal in a first mode and disable the signal generator circuit to stop generating the supplemental signal in a second mode.

44. The sensor device of claim 43, wherein the control circuit is configured to automatically determine to operate in one of the first mode and the second mode.

45. The sensor device of claim 44, wherein the control circuit is configured to: receiving a monitoring voltage of the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal; and Operating in one of the first mode and the second mode is automatically determined based on the monitored voltage.

46. ​​The sensor device of claim 43, further comprising: at least one actuator for receiving user input; Wherein the control circuit is configured to determine to operate in one of the first mode and the second mode in response to actuation of the at least one actuator.

47. The sensor device of claim 43, further comprising: a communication circuit configured to receive a message; Wherein the control circuit is configured to determine to operate in one of the first mode and the second mode in response to the message received via the communication circuit.

48. The sensor device of claim 21, wherein the signal generation control circuit is configured to generate the supplemental signal as a sinusoidal signal characterized by the ultrasonic frequency.

49. The sensor device of claim 48, wherein the control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplemental signal.

50. The sensor device of claim 49, wherein the signal generator circuit is configured to generate the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal.

51. The sensor device of claim 50, wherein the control circuit is configured to generate a magnitude adjustment control signal, the magnitude adjustment control signal being received by the signal generator circuit for adjusting a peak-to-peak magnitude of the supplemental signal.

52. The sensor device of claim 51, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal in response to a noise floor of the detection signal generated by the ultrasonic receiving circuit.

53. A sensor device as described in claim 52, wherein the control circuit is configured to adjust the peak-to-peak value of the supplementary signal to a first value when the value of the noise floor of the detection signal is less than a threshold value, and to adjust the peak-to-peak value of the supplementary signal to a second value when the value of the noise floor of the detection signal is greater than the threshold value, wherein the second value is less than the first value.

54. The sensor device of claim 53, wherein the signal generator circuit comprises a two-stage filter circuit comprising a first resistor-capacitor circuit configured to receive the signal generation control signal and a second resistor-capacitor circuit configured to generate the supplemental signal; and The signal generator circuit further includes a variable attenuator circuit coupled between a connection point of the first resistor-capacitor circuit and the second resistor-capacitor circuit and a circuit common terminal, wherein the variable attenuator circuit is configured to adjust an equivalent impedance of the second resistor-capacitor circuit to adjust the peak-to-peak magnitude of the supplementary signal.

55. A sensor device as described in claim 54, wherein the variable attenuator circuit includes a parallel combination of a resistor and a capacitor coupled in series with a transistor, and the control circuit is configured to render the transistor non-conductive to adjust the peak-to-peak magnitude of the supplemental signal to the first magnitude, and to render the transistor conductive to adjust the peak-to-peak magnitude of the supplemental signal to the second magnitude.

56. The sensor device of claim 52, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal based on the magnitude of the noise floor of the detection signal.

57. A sensor device as described in claim 56, wherein the control circuit includes a digital-to-analog converter for adjusting the DC value of the value adjustment control signal, and the signal generator circuit is configured to adjust the peak-to-peak value in response to the DC value of the value adjustment control signal.

58. The sensor device of claim 52, wherein the control circuit is configured to automatically adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

59. The sensor device of claim 52, wherein the control circuit is configured to determine the noise floor of the detection signal in response to a magnitude of the detection signal.

60. The sensor device of claim 59, wherein the control circuit is configured to pulse width modulate the signal generation control signal at the ultrasonic frequency, and the signal generator circuit is configured to filter the signal generation control signal to generate the supplemental signal.

61. The sensor device of claim 59, wherein the signal generator circuit comprises an integrated circuit configured to generate a pulse width modulated signal at the ultrasonic frequency and a filter circuit configured to receive the pulse width modulated signal and generate the supplemental signal.

62. The sensor device of claim 21, wherein the ultrasonic receiving circuit comprises: an amplifier circuit configured to amplify the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; an envelope detector circuit configured to receive the amplified signal and generate an envelope signal; as well as A filter circuit is configured to filter the envelope signal to generate the detection signal.

63. A sensor device as described in claim 62, wherein the envelope detector circuit includes a capacitor, which is configured to be charged from the amplified voltage through a diode to generate the envelope signal across the capacitor, and wherein the peak magnitude of the supplemental signal and the gain of the amplifier circuit are sized to ensure that the peak magnitude of the amplified signal exceeds the forward voltage drop of the diode of the envelope detector circuit.

64. A sensor device as described in claim 62, wherein the control circuit is configured to enable the signal generator circuit to generate the supplemental signal in a first mode and disable the signal generator circuit to stop generating the supplemental signal in a second mode, and the control circuit is further configured to receive a filtered version of the envelope signal and determine to operate in one of the first mode and the second mode in response to the magnitude of the filtered version of the envelope signal.

65. The sensor device of claim 62, wherein the control circuit is configured to receive a filtered version of the envelope signal and to adjust a phase of the supplemental signal in response to a magnitude of the filtered version of the envelope signal.

66. The sensor device of claim 21, wherein the ultrasonic receiving element comprises a first ultrasonic receiving element, the signal generator circuit comprises a first signal generator circuit, and the ultrasonic receiving circuit comprises a first ultrasonic receiving circuit configured to generate a first detection signal; and The sensor device further comprises: a second ultrasonic wave receiving element configured to receive an ultrasonic wave characterized by the ultrasonic wave frequency and generate a second ultrasonic wave receiving voltage signal; a second signal generator circuit configured to generate a second supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; and a second ultrasonic receiving circuit configured to receive a combination of the second ultrasonic receiving voltage signal and the second supplemental signal, the second ultrasonic receiving circuit configured to generate a second detection signal indicating when the space is occupied; Wherein the control circuit is further configured to receive the second detection signal and detect an occupancy condition in the space in response to the second detection signal.

67. The sensor device of claim 66, wherein the control circuit is configured to detect an occupancy condition in the space in response to both the first detection signal and the second detection signal, in response to only the first detection signal, or in response to only the second detection signal.

68. The sensor device of claim 67, further comprising: at least one actuator for receiving user input; Wherein the control circuit is configured to determine, in response to actuation of the at least one actuator, whether to be responsive to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal.

69. The sensor device of claim 67, further comprising: a communication circuit configured to receive a message; Wherein the control circuit is configured to determine, in response to the message received via the communication circuit, whether to respond to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal.

70. The sensor device of claim 21, wherein the control circuit is configured to automatically configure operation of the signal generating circuit when the space is vacant.

71. The sensor device of claim 70, further comprising: passive infrared detection circuitry including a pyroelectric detector configured to receive infrared energy from an occupant in the space; Wherein the control circuit is configured to automatically configure the operation of the signal generation circuit when the control circuit has determined, in response to the passive infrared detection circuit, that the space is vacant.

72. The sensor device of claim 21, further comprising: A housing, the housing being used to accommodate the ultrasonic receiving element, the signal generator circuit, the ultrasonic receiving circuit and the control circuit; The housing includes an opening in a front surface of the housing, the ultrasonic wave receiving element is configured to receive the ultrasonic wave through the opening, a diameter of the opening is approximately equal to a wavelength of the ultrasonic wave, and a depth between the front surface of the housing and the ultrasonic wave receiving element is approximately equal to one quarter of the wavelength of the ultrasonic wave.

73. A method for detecting occupancy conditions in a space, the method comprising: receiving an ultrasonic wave by an ultrasonic wave receiving element, wherein the ultrasonic wave comprises a non-Doppler frequency shifted ultrasonic wave when the space is vacant and comprises a combination of a non-Doppler frequency shifted ultrasonic wave and a Doppler frequency shifted wave when the space is occupied, the non-Doppler frequency shifted ultrasonic wave being characterized by an ultrasonic frequency; generating an ultrasonic wave reception voltage signal in response to the ultrasonic wave received by the ultrasonic wave receiving element; generating a supplemental signal characterized by the ultrasonic frequency; combining the supplementary signal with the ultrasonic reception voltage signal; generating, by an ultrasonic receiving circuit, a detection signal indicating when the space is occupied in response to a combination of the ultrasonic receiving voltage signal and the supplemental signal; and The occupancy condition in the space is detected in response to the detection signal.

74. The method of claim 73, further comprising: A signal generation control signal for controlling generation of the supplemental signal is generated.

75. The method of claim 74, wherein generating a signal generation control signal further comprises controlling the signal generation control signal to enable and disable generation of the supplemental signal.

76. The method of claim 75, further comprising: driving the ultrasonic emitting element so that the ultrasonic emitting element emits ultrasonic waves; An ultrasonic wave driving signal is generated for controlling the emission of the ultrasonic wave.

77. The method of claim 76, wherein the ultrasonic wave received by the ultrasonic wave receiving element is characterized by a phase delay compared to the ultrasonic wave transmitted by the ultrasonic wave transmitting element, and wherein generating a signal generation control signal further comprises pulse width modulating the signal generation control signal at the ultrasonic wave frequency.

78. The method of claim 77, further comprising: The phase of the signal generation control signal is adjusted compared to the ultrasonic drive signal so as to adjust the phase of the supplemental signal.

79. The method of claim 78, further comprising: receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

80. The method of claim 79, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is disabled; as well as Generation of the supplemental signal is automatically configured in response to the monitoring voltage when the space is vacant.

81. The method of claim 80, further comprising: A configuration process is periodically performed to automatically configure generation of the supplemental signal in response to the monitored voltage when the space is vacant.

82. The method of claim 80, further comprising: The ultrasonic wave transmitting element is controlled to transmit the ultrasonic wave, while the generation of the supplementary signal is configured in response to the monitoring voltage.

83. The method of claim 79, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is disabled; as well as Generation of the supplemental signal is enabled when the magnitude of the monitored voltage is less than a threshold.

84. The method of claim 79, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is enabled; determining to adjust the phase of the signal generation control signal when the magnitude of the monitored voltage is less than a threshold; as well as The phase of the supplemental signal is adjusted until the magnitude of the monitored voltage is greater than the threshold.

85. The method of claim 76, wherein generating a signal generation control signal further comprises pulse width modulating the signal generation control signal at the ultrasonic frequency.

86. The method of claim 85, further comprising: receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

87. The method of claim 87, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is disabled; as well as Generation of the supplemental signal is automatically configured in response to the monitoring voltage when the space is vacant.

88. The method of claim 88, further comprising: A configuration process is periodically performed to automatically configure generation of the supplemental signal in response to the monitored voltage when the space is vacant.

89. The method of claim 87, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is disabled; as well as Generation of the supplemental signal is enabled when the magnitude of the monitored voltage is less than a threshold.

90. The method of claim 90, further comprising: Generation of the supplemental signal is disabled when the magnitude of the monitored voltage is greater than the threshold.

91. The method of claim 87, further comprising: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when generation of the supplemental signal is enabled; as well as The phase of the signal generation control signal is adjusted when the magnitude of the monitored voltage is less than a threshold value.

92. The method of claim 92, further comprising: The phase of the supplemental signal is adjusted until the magnitude of the monitored voltage is greater than the threshold.

93. The method of claim 86, further comprising: The phase of the supplemental signal is adjusted when the control circuit determines that the supplemental signal is out of phase with the received ultrasonic wave.

94. The method of claim 94, further comprising: The phase of the supplemental signal is adjusted until the supplemental signal is not out of phase with the received ultrasonic wave.

95. The method of claim 76, further comprising: enabling generation of the supplemental signal in a first mode; as well as In the second mode the generation of the supplementary signal is disabled.

96. The method of claim 96, further comprising: Automatically determine to operate in one of the first mode and the second mode.

97. The method of claim 99, further comprising: receiving a monitoring voltage of the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal; as well as Operating in one of the first mode and the second mode is automatically determined based on the monitored voltage.

98. The method of claim 96, further comprising: detecting actuation of the actuator; as well as Operating in one of the first mode and the second mode is determined in response to detecting the actuation of the actuator.

99. The method of claim 96, further comprising: Receive messages; as well as A determination is made to operate in one of the first mode and the second mode in response to receiving the message.

100. The method of claim 74, wherein generating a supplemental signal further comprises generating the supplemental signal as a sinusoidal signal characterized by the ultrasonic frequency.

101. The method of claim 101, further comprising: A signal generation control signal for controlling generation of the supplemental signal is generated.

102. The method of claim 102, wherein generating a supplemental signal further comprises generating the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal.

103. The method of claim 103, further comprising: A peak-to-peak magnitude of the supplemental signal is adjusted in response to a noise floor of the detection signal generated by the ultrasonic receive circuit.

104. A method as claimed in claim 104, wherein adjusting the peak-to-peak magnitude of the supplementary signal further includes adjusting the peak-to-peak magnitude of the supplementary signal to a first magnitude when the magnitude of the noise floor of the detection signal is less than a threshold value, and adjusting the peak-to-peak magnitude of the supplementary signal to a second magnitude when the magnitude of the noise floor of the detection signal is greater than the threshold value, wherein the second magnitude is less than the first magnitude.

105. The method of claim 104, wherein adjusting the peak-to-peak magnitude of the supplemental signal further comprises adjusting the peak-to-peak magnitude of the supplemental signal based on a magnitude of the noise floor of the detection signal.

106. The method of claim 104, wherein adjusting the peak-to-peak magnitude of the supplemental signal further comprises automatically adjusting the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

107. The method of claim 104, further comprising: The noise floor of the detection signal is determined responsive to a magnitude of the detection signal.

108. The method of claim 102, wherein generating a signal generation control signal further comprises pulse width modulating the signal generation control signal at the ultrasonic frequency and filtering the signal generation control signal to generate the supplemental signal.

109. The method of claim 1, wherein generating a detection signal indicating when the space is occupied further comprises: amplifying the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; generating an envelope signal from the amplified signal; as well as The envelope signal is filtered to generate the detection signal.

110. The method of claim 110, further comprising: enabling generation of the supplemental signal in a first mode; as well as disabling generation of the supplemental signal in a second mode; receiving a filtered version of the envelope signal; as well as Operating in one of the first mode and the second mode is determined responsive to a magnitude of the filtered version of the envelope signal.

111. The method of claim 110, further comprising: receiving a filtered version of the envelope signal; as well as The phase of the supplemental signal is adjusted responsive to a magnitude of the filtered version of the envelope signal.

112. The method of claim 74, further comprising: determining that the space is vacant; as well as The generation of the supplemental signal is automatically configured in response to determining that the space is vacant.

113. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; a control circuit configured to control generation of a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; an ultrasonic receiving circuit configured to receive a combination of the ultrasonic receiving voltage signal and the supplemental signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied; and The control circuit is configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal, and the control circuit is further configured to enable generation of the supplementary signal to ensure that the combination of the ultrasonic receiving voltage signal and the supplementary signal can be correctly processed by the ultrasonic receiving circuit to generate the detection signal.

114. The sensor device of claim 114, further comprising: a signal generator circuit configured to generate a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; The control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplementary signal.

115. The sensor device of claim 115, wherein the control circuit is configured to: The signal generation control signal is pulse width modulated at the ultrasonic frequency when the signal generator circuit is enabled.

116. The sensor device of claim 116, wherein the control circuit is configured to: receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

117. A sensor device as described in claim 117, wherein the control circuit is configured to measure the magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled, and determine to adjust the phase of the signal generating control signal when the magnitude of the monitoring voltage is less than a threshold value.

118. The sensor device of claim 118, wherein the control circuit is configured to adjust a phase of the supplemental signal until the magnitude of the monitored voltage is greater than the threshold.

119. A sensor device as described in claim 117, wherein the control circuit is configured to measure the magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and the control circuit is further configured to enable the signal generating circuit when the magnitude of the monitoring voltage is less than a threshold value, and disable the signal generating circuit when the magnitude of the monitoring voltage is greater than the threshold value.

120. The sensor device of claim 117, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and to automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

121. The sensor device of claim 117, wherein the ultrasonic receiving circuit comprises: an amplifier circuit configured to amplify the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; an envelope detector circuit configured to receive the amplified signal and generate an envelope signal; as well as a filter circuit configured to filter the envelope signal to generate the detection signal; Wherein the monitoring voltage is a filtered version of the envelope signal.

122. A sensor device as described in claim 115, wherein the signal generator circuit is configured to generate the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal, and the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal generated by the ultrasonic receiving circuit.

123. A sensor device as described in claim 123, wherein the control circuit is configured to adjust the peak-to-peak value of the supplementary signal to a first value when the value of the noise floor of the detection signal is less than a threshold value, and to adjust the peak-to-peak value of the supplementary signal to a second value when the value of the noise floor of the detection signal is greater than the threshold value, wherein the second value is less than the first value.

124. The sensor device of claim 123, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal based on the magnitude of the noise floor of the detection signal.

125. The sensor device of claim 123, wherein the control circuit is configured to automatically adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

126. The sensor device of claim 123, wherein the control circuit is configured to determine the noise floor of the detection signal in response to a magnitude of the detection signal.

127. The sensor device of claim 115, wherein the control circuit is configured to enable the signal generator circuit to generate the supplemental signal in a first mode and disable the signal generator circuit to stop generating the supplemental signal in a second mode.

128. The sensor device of claim 128, wherein the control circuit is configured to automatically determine to operate in one of the first mode and the second mode.

129. The sensor device of claim 129, wherein the control circuit is configured to: receiving a monitoring voltage of the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal; and Operating in one of the first mode and the second mode is automatically determined based on the monitored voltage.

130. The sensor device of claim 128, further comprising: at least one actuator for receiving user input; Wherein the control circuit is configured to determine to operate in one of the first mode and the second mode in response to actuation of the at least one actuator.

131. The sensor device of claim 128, further comprising: a communication circuit configured to receive a message; Wherein the control circuit is configured to determine to operate in one of the first mode and the second mode in response to the message received via the communication circuit.

132. The sensor device of claim 115, wherein the control circuit is configured to adjust a phase of the supplemental signal when the control circuit determines that the supplemental signal is out of phase with the received ultrasonic wave.

133. The sensor device of claim 133, wherein the control circuit is configured to adjust the phase of the supplemental signal until the control circuit determines that the supplemental signal is not out of phase with the received ultrasonic wave.

134. The sensor device of claim 134, wherein the control circuit is configured to automatically enable and disable generation of the supplemental signal when the space is vacant.

135. The sensor device of claim 134, wherein the control circuit is configured to directly generate the supplemental signal.

136. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; a control circuit configured to control generation of a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; an ultrasonic receiving circuit configured to receive a combination of the ultrasonic receiving voltage signal and the supplemental signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied; and The control circuit is configured to adjust the phase of the signal generation control signal when the magnitude of the monitoring voltage is less than a threshold value to ensure that the combination of the ultrasonic receiving voltage signal and the supplementary signal can be correctly processed by the ultrasonic receiving circuit to generate the detection signal.

137. The sensor device of claim 138, further comprising: a signal generator circuit configured to generate a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; The control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplementary signal.

138. The sensor device of claim 139, wherein the control circuit is configured to: The signal generation control signal is pulse width modulated at the ultrasonic frequency.

139. The sensor device of claim 140, wherein the control circuit is configured to: receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

140. The sensor device of claim 141, wherein the control circuit is configured to measure a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the supplemental signal is generated, and to determine to adjust a phase of the signal generation control signal when the magnitude of the monitoring voltage is less than a threshold.

141. The sensor device of claim 142, wherein the control circuit is configured to adjust a phase of the supplemental signal until the magnitude of the monitored voltage is greater than the threshold.

142. The sensor device of claim 141, wherein the control circuit is configured to control the signal generation control to enable and disable the signal generator circuit.

143. A sensor device as described in claim 144, wherein the control circuit is configured to measure the value of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and the control circuit is further configured to enable the signal generating circuit when the value of the monitoring voltage is less than a threshold value, and disable the signal generating circuit when the value of the monitoring voltage is greater than the threshold value.

144. A sensor device as described in claim 141, wherein the control circuit is configured to measure the magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

145. The sensor device of claim 141, wherein the ultrasonic receiving circuit comprises: an amplifier circuit configured to amplify the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; an envelope detector circuit configured to receive the amplified signal and generate an envelope signal; as well as a filter circuit configured to filter the envelope signal to generate the detection signal; Wherein the monitoring voltage is a filtered version of the envelope signal.

146. The sensor device of claim 140, wherein the control circuit is configured to adjust the phase of the supplemental signal when the control circuit determines that the supplemental signal is out of phase with the received ultrasonic wave.

147. The sensor device of claim 148, wherein the control circuit is configured to adjust the phase of the supplemental signal until the control circuit determines that the supplemental signal is not out of phase with the received ultrasonic wave.

148. A sensor device as described in claim 139, wherein the signal generator circuit is configured to generate the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal, and the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal generated by the ultrasonic receiving circuit.

149. A sensor device as described in claim 150, wherein the control circuit is configured to adjust the peak-to-peak value of the supplementary signal to a first value when the value of the noise floor of the detection signal is less than a threshold value, and to adjust the peak-to-peak value of the supplementary signal to a second value when the value of the noise floor of the detection signal is greater than the threshold value, wherein the second value is less than the first value.

150. The sensor device of claim 150, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal based on the magnitude of the noise floor of the detection signal.

151. The sensor device of claim 150, wherein the control circuit is configured to automatically adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

152. The sensor device of claim 150, wherein the control circuit is configured to determine the noise floor of the detection signal in response to a magnitude of the detection signal.

153. The sensor device of claim 139, further comprising: An ultrasonic transmitting unit, wherein the ultrasonic transmitting unit is configured to transmit ultrasonic waves; as well as an ultrasonic wave transmitting circuit, wherein the ultrasonic wave transmitting circuit is configured to drive the ultrasonic wave transmitting element so that the ultrasonic wave transmitting element transmits the ultrasonic wave; The control circuit is configured to generate an ultrasonic wave driving signal, and the ultrasonic wave driving signal is received by the ultrasonic wave transmitting circuit to control the ultrasonic wave transmitting element to transmit the ultrasonic wave.

154. The sensor device of claim 155, wherein the ultrasonic wave received by the ultrasonic wave receiving element is characterized by a phase delay compared to the ultrasonic wave transmitted by the ultrasonic wave transmitting element; and The control circuit is configured to pulse width modulate the signal generation control signal at the ultrasonic frequency and adjust the phase of the signal generation control signal compared to the ultrasonic drive signal so as to adjust the phase of the supplemental signal.

155. The sensor device of claim 139, wherein the control circuit is configured to: receiving a monitoring voltage of the ultrasonic receiving circuit, wherein the monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal; measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled; determining to adjust the phase of the signal generation control signal when the magnitude of the monitored voltage is less than a threshold; as well as The phase of the supplemental signal is adjusted until the magnitude of the monitored voltage is greater than the threshold.

156. The sensor device of claim 138, wherein the control circuit is configured to automatically enable and disable generation of the supplemental signal when the space is vacant.

157. The sensor device of claim 138, wherein the control circuit is configured to directly generate the supplemental signal.

158. The sensor device of claim 138, wherein the control circuit is configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal.

159. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; a control circuit configured to control generation of a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; an ultrasonic receiving circuit configured to receive a combination of the ultrasonic receiving voltage signal and the supplemental signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied; and Wherein the control circuit is configured to adjust a peak-to-peak magnitude of the supplemental signal in response to a noise floor of the detection signal generated by the ultrasonic receiving circuit.

160. The sensor device of claim 161, further comprising: a signal generator circuit configured to generate a supplemental signal characterized by the ultrasonic frequency and combined with the ultrasonic receive voltage signal; The control circuit is configured to generate a signal generation control signal, which is received by the signal generator circuit for controlling the generation of the supplementary signal.

161. The sensor device of claim 162, wherein the signal generator circuit is configured to generate the supplemental signal as a sinusoidal signal at the ultrasonic frequency in response to the signal generation control signal.

162. A sensor device as described in claim 163, wherein the control circuit is configured to adjust the peak-to-peak value of the supplementary signal to a first value when the value of the noise floor of the detection signal is less than a threshold value, and to adjust the peak-to-peak value of the supplementary signal to a second value when the value of the noise floor of the detection signal is greater than the threshold value, wherein the second value is less than the first value.

163. The sensor device of claim 163, wherein the control circuit is configured to adjust the peak-to-peak magnitude of the supplemental signal based on the magnitude of the noise floor of the detection signal.

164. The sensor device of claim 163, wherein the control circuit is configured to automatically adjust the peak-to-peak magnitude of the supplemental signal in response to the noise floor of the detection signal when the space is vacant.

165. The sensor device of claim 163, wherein the control circuit is configured to determine the noise floor of the detection signal in response to a magnitude of the detection signal.

166. The sensor device of claim 162, wherein the control circuit is configured to: pulse width modulating the signal generation control signal at the ultrasonic frequency when the signal generator circuit is enabled; and receiving a monitoring voltage of the ultrasonic receiving circuit; The monitoring voltage has a magnitude indicating that the combination of the ultrasonic receiving voltage signal and the supplemental signal can be properly processed by the ultrasonic receiving circuit to generate the detection signal.

167. The sensor device of claim 168, wherein the control circuit is configured to: measuring a magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is enabled; determining to adjust the phase of the signal generation control signal when the magnitude of the monitored voltage is less than a threshold; as well as The phase of the supplemental signal is adjusted until the magnitude of the monitored voltage is greater than the threshold.

168. A sensor device as described in claim 168, wherein the control circuit is configured to measure the value of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and the control circuit is further configured to enable the signal generating circuit when the value of the monitoring voltage is less than a threshold value, and disable the signal generating circuit when the value of the monitoring voltage is greater than the threshold value.

169. A sensor device as described in claim 168, wherein the control circuit is configured to measure the magnitude of the monitoring voltage of the ultrasonic receiving circuit when the signal generating circuit is disabled, and automatically configure the operation of the signal generating circuit in response to the monitoring voltage when the space is vacant.

170. The sensor device of claim 168, wherein the ultrasonic receiving circuit comprises: an amplifier circuit configured to amplify the combination of the ultrasonic reception voltage signal and the supplemental signal to generate an amplified signal; an envelope detector circuit configured to receive the amplified signal and generate an envelope signal; as well as a filter circuit configured to filter the envelope signal to generate the detection signal; Wherein the monitoring voltage is a filtered version of the envelope signal.

171. The sensor device of claim 161, wherein the control circuit is configured to automatically enable and disable generation of the supplemental signal when the space is vacant.

172. The sensor device of claim 161, wherein the control circuit is configured to directly generate the supplemental signal.

173. The sensor device of claim 161, wherein the control circuit is configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal.

174. A sensor device configured to be installed in a space, the sensor device comprising: a first ultrasonic wave receiving element configured to receive ultrasonic waves and generate a first ultrasonic wave receiving voltage signal; a first ultrasonic receiving circuit configured to receive the first ultrasonic receiving voltage signal, the first ultrasonic receiving circuit configured to generate a first detection signal indicating when the space is occupied in response to the first ultrasonic receiving voltage; a second ultrasonic wave receiving element configured to receive ultrasonic waves and generate a second ultrasonic wave receiving voltage signal; a second ultrasonic receiving circuit configured to receive the second ultrasonic receiving voltage signal, the second ultrasonic receiving circuit configured to generate a second detection signal indicating when the space is occupied in response to the first ultrasonic receiving voltage signal; as well as A control circuit is configured to receive the first detection signal and the second detection signal, and the control circuit is further configured to detect an occupancy condition in the space in response to both the first detection signal and the second detection signal, in response to only the first detection signal, or in response to only the second detection signal.

175. The sensor device of claim 176, wherein the ultrasonic wave comprises a non-Doppler shifted ultrasonic wave when the space is vacant and comprises a combination of a non-Doppler shifted ultrasonic wave and a Doppler shifted wave when the space is occupied, the non-Doppler shifted ultrasonic wave being characterized by an ultrasonic frequency.

176. The sensor device of claim 177, wherein the control circuit is configured to control generation of a first supplemental signal and a second supplemental signal each characterized by the ultrasonic frequency; wherein the first ultrasonic receiving circuit is configured to receive a combination of the first ultrasonic receiving voltage signal and the first supplementary signal, and the first ultrasonic receiving circuit is configured to generate the first detection signal; and The second ultrasonic receiving circuit is configured to receive a combination of the second ultrasonic receiving voltage signal and the second supplementary signal, and the second ultrasonic receiving circuit is configured to generate the second detection signal.

177. The sensor device of claim 178, further comprising: a first signal generator circuit configured to generate the first supplemental signal combined with the first ultrasonic reception voltage signal; as well as A second signal generator circuit is configured to generate the second supplemental signal combined with the second ultrasonic reception voltage signal.

178. The sensor device of claim 176, further comprising: at least one actuator for receiving user input; Wherein the control circuit is configured to determine, in response to actuation of the at least one actuator, whether to be responsive to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal.

179. The sensor device of claim 176, further comprising: a communication circuit configured to receive a message; Wherein the control circuit is configured to determine, in response to the message received via the communication circuit, whether to respond to both the first detection signal and the second detection signal, only the first detection signal, or only the second detection signal.

180. A sensor device configured to be installed in a space, the sensor device comprising: an ultrasonic wave receiving element configured to receive ultrasonic waves and generate ultrasonic wave receiving voltage signals, wherein the ultrasonic waves include non-Doppler frequency shifted ultrasonic waves when the space is vacant and include a combination of non-Doppler frequency shifted ultrasonic waves and Doppler frequency shifted waves when the space is occupied, the non-Doppler frequency shifted ultrasonic waves being characterized by ultrasonic frequency; an ultrasonic receiving circuit configured to receive the ultrasonic receiving voltage signal, the ultrasonic receiving circuit configured to generate a detection signal indicating when the space is occupied in response to the ultrasonic receiving voltage; a control circuit configured to receive the detection signal and detect an occupancy condition in the space in response to the detection signal; as well as A housing, the housing being used to accommodate the ultrasonic receiving element, the signal generator circuit, the ultrasonic receiving circuit and the control circuit; The housing includes an opening in a front surface of the housing, the ultrasonic wave receiving element is configured to receive the ultrasonic wave through the opening, a diameter of the opening is approximately equal to a wavelength of the ultrasonic wave, and a depth between the front surface of the housing and the ultrasonic wave receiving element is approximately equal to one quarter of the wavelength of the ultrasonic wave.

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