Occupant detection system for a vehicle comprising a multiband transceiver

Abstract

An occupant detection system for the interior compartment area of ​​a vehicle includes: one or more signal conversion devices including conversion circuitry; and a wireless control module including a multi-band transceiver having two or more transceivers. The wireless control module executes instructions to continuously transmit signals in a first frequency band via a first transceiver. The wireless control module executes instructions to receive signals in a second frequency band from the signal conversion devices via a second transceiver. The wireless control module compares raw training symbols from the signals in the first frequency band with training symbols from the signals in the second frequency band to determine changes in the values ​​of one or more Channel State Information (CSI) parameters, and determines the presence of one or more occupants in the interior compartment area of ​​the vehicle based on the changes in the one or more CSI parameters.

Description

Technical Field

[0001] This disclosure relates to an occupant detection system that detects the presence of one or more occupants within an interior compartment area of ​​a vehicle based on channel state information (CSI) estimation. The occupant detection system includes a wireless control module having a multi-band transceiver that wirelessly communicates with one or more signal conversion devices. Background Technology

[0002] Occupant detection systems can be used to detect the presence of individuals within the interior compartments of a vehicle. Various technologies exist for detecting the presence of individuals within the interior compartments of a vehicle. For example, one type of occupant detection system may include weight sensors placed within the vehicle's seats to detect the presence of an individual. However, weight sensors can be expensive and are primarily used only in high-end or luxury vehicles. Camera-based systems also exist for detecting occupants in the interior compartments; however, cameras may introduce privacy-related issues. Small-scale radio frequency (RF) sensors, such as radar sensors, can also be used; however, these sensors are also relatively expensive.

[0003] Wireless sensing technology can be used to detect events or changes in the surrounding environment based on CSI estimation. Wireless sensing technology reuses existing infrastructure already used for wireless communication and is therefore cost-effective and relatively easy to deploy. CSI estimation represents how a wireless signal propagates from the transmitter to the receiver along multiple paths at certain carrier frequencies. However, wireless sensing technology requires two or more wireless control modules to be installed in the vehicle for presence detection, while most currently available vehicles only include a single wireless control module. Introducing additional wireless modules increases the cost and complexity of the vehicle.

[0004] Therefore, while current occupant detection systems have achieved their intended purpose, there is a need in the art for an improved, cost-effective method for detecting occupants inside vehicles. Summary of the Invention

[0005] According to several aspects, an occupant detection system for the interior compartment area of ​​a vehicle is disclosed. The occupant detection system includes one or more signal conversion devices, each including conversion circuitry and a wireless control module, the wireless control module including a multi-band transceiver having two or more transceivers. The wireless control module executes instructions to continuously transmit signals in a first frequency band via a first transceiver. The signals include data packets containing original training symbols. The wireless control module executes instructions to receive signals in a second frequency band from the signal conversion device via a second transceiver, wherein the conversion circuitry of the signal conversion device converts the signals in the first frequency band into signals in the second frequency band. The wireless control module executes instructions to compare the original training symbols from the signals in the first frequency band with the training symbols from the signals in the second frequency band to determine changes in the values ​​of one or more Channel State Information (CSI) parameters. The wireless control module executes instructions to determine the presence of one or more occupants in the interior compartment area of ​​the vehicle based on changes in one or more CSI parameters.

[0006] On one hand, one or more signal conversion devices include a power source that supplies power to the conversion circuit.

[0007] On the other hand, the power source is a battery or an energy harvesting device.

[0008] On the other hand, energy harvesting devices capture energy from one or more of the following: radio frequency, light, vibration, and heat.

[0009] In one aspect, the conversion circuit of each of one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter.

[0010] On the other hand, the combined low-noise amplifier and bandpass filter include a bandpass filter having a passband with a center frequency at a first bandpass frequency.

[0011] In another aspect, the conversion circuit of each of one or more signal conversion devices includes a mixer and a local oscillator, which converts a signal in a first frequency band into a signal in a second frequency band.

[0012] In one aspect, the conversion circuit of each of one or more signal conversion devices includes a bandpass filter having a passband with a center frequency equal to a second bandpass frequency.

[0013] On the other hand, the wireless control module supports wireless communication protocols that use training symbols to perform CSI estimation.

[0014] On the other hand, one or more signal conversion devices are radio frequency (RF) tags.

[0015] On the one hand, the vehicle's interior compartment area includes the vehicle's cargo area.

[0016] On the other hand, the vehicle's interior compartment area includes the area immediately adjacent to the interior compartment area, which is within the wireless sensing proximity range of the wireless control module.

[0017] On one hand, CSI parameters include amplitude, phase, and signal delay.

[0018] On the other hand, the occupant detection system also includes multiple signal conversion devices, each of which is assigned to a corresponding seat in the vehicle's interior compartment area.

[0019] In one aspect, a method for detecting the presence of an occupant within an interior compartment area of ​​a vehicle using an occupant detection system. The method includes continuously transmitting signals in a first frequency band by a first transceiver, which is part of a radio control module. The signals include data packets containing original training symbols. The method also includes receiving signals in a second frequency band from a signal conversion device by a second transceiver, which is also part of the radio control module. A conversion circuit of the signal conversion device converts the signals in the first frequency band into signals in the second frequency band. The method further includes comparing the original training symbols from the signals in the first frequency band with training symbols from the signals in the second frequency band to determine changes in the values ​​of one or more Channel State Information (CSI) parameters. Finally, the method includes determining the presence of one or more occupants within the interior compartment area of ​​the vehicle based on the changes in one or more CSI parameters.

[0020] In one aspect, an occupant detection system for the interior compartment area of ​​a vehicle is disclosed. The occupant detection system includes one or more signal conversion devices, each including conversion circuitry. Each of the one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter, a mixer, and a local oscillator, as well as a second bandpass filter. The occupant detection system also includes a wireless control module, comprising a multi-band transceiver with two or more transceivers. The wireless control module executes instructions to continuously transmit signals in a first frequency band by a first transceiver, wherein these signals include data packets containing original training symbols. The wireless control module executes instructions to receive signals in a second frequency band from the signal conversion devices via a second transceiver. The conversion circuitry of the signal conversion devices converts the signals in the first frequency band into signals in the second frequency band. The wireless control module executes instructions to compare the original training symbols from the signals in the first frequency band with the training symbols from the signals in the second frequency band to determine changes in the values ​​of one or more Channel State Information (CSI) parameters. Finally, the wireless control module executes instructions to determine the presence of one or more occupants in the interior compartment area of ​​the vehicle based on changes in one or more CSI parameters.

[0021] In one aspect, the combined low-noise amplifier and bandpass filter includes a bandpass filter having a passband having a center frequency at a first bandpass frequency.

[0022] On the other hand, the mixer and local oscillator convert the signal in the first frequency band into a signal in the second frequency band.

[0023] On the other hand, a bandpass filter has a passband whose center frequency is equal to the second bandpass frequency.

[0024] On one hand, the wireless control module supports wireless communication protocols that use training symbols to perform CSI estimation.

[0025] The present invention also includes the following solutions:

[0026] Solution 1. An occupant detection system for the interior compartment area of ​​a vehicle, the occupant detection system comprising:

[0027] One or more signal conversion devices, including conversion circuitry; and

[0028] A wireless control module, comprising a multi-band transceiver having two or more transceivers, wherein the wireless control module executes instructions to:

[0029] A first transceiver continuously transmits signals in a first frequency band, wherein the signals include data packets containing original training symbols;

[0030] The signal in the second frequency band is received from the signal conversion device via the second transceiver, wherein the conversion circuit of the signal conversion device converts the signal in the first frequency band into the signal in the second frequency band;

[0031] The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine changes in the values ​​of one or more channel state information (CSI) parameters; and

[0032] The presence of one or more occupants in the vehicle's interior compartment area is determined based on changes in one or more CSI parameters.

[0033] Option 2. The occupant detection system according to Option 1, wherein each of the one or more signal conversion devices includes a power source that supplies power to the conversion circuit.

[0034] Option 3. The occupant detection system according to Option 2, wherein the power source is a battery or an energy harvesting device.

[0035] Option 4. The occupant detection system according to Option 3, wherein the energy harvesting device captures energy from one or more of the following: radio frequency, light, vibration, and heat.

[0036] Option 5. The occupant detection system according to Option 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter.

[0037] Option 6. The occupant detection system according to Option 5, wherein the combined low-noise amplifier and bandpass filter include a bandpass filter having a passband having a center frequency at a first bandpass frequency.

[0038] Option 7. The occupant detection system according to Option 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a mixer and a local oscillator for converting a signal in the first frequency band into a signal in the second frequency band.

[0039] Option 8. The occupant detection system according to Option 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a bandpass filter having a passband with a center frequency equal to a second bandpass frequency.

[0040] Option 9. The occupant detection system according to Option 1, wherein the wireless control module supports a wireless communication protocol that uses training symbols to perform CSI estimation.

[0041] Option 10. The occupant detection system according to Option 1, wherein the one or more signal conversion devices are radio frequency (RF) tags.

[0042] Option 11. The occupant detection system according to Option 1, wherein the interior compartment area of ​​the vehicle includes the cargo area of ​​the vehicle.

[0043] Option 12. The occupant detection system according to Option 1, wherein the interior compartment area of ​​the vehicle includes an area immediately outside the interior compartment area, the area being within the wireless sensing proximity of the wireless control module.

[0044] Option 13. The occupant detection system according to Option 1, wherein the CSI parameters include amplitude, phase and signal delay.

[0045] Option 14. The occupant detection system according to Option 1 further includes multiple signal conversion devices, each of which is assigned to a corresponding seat in the interior compartment area of ​​the vehicle.

[0046] Option 15. A method for detecting the presence of occupants in an interior compartment area of ​​a vehicle using an occupant detection system, the method comprising:

[0047] A first transceiver, which is part of a wireless control module, continuously transmits signals on a first frequency band, wherein the signals include data packets containing original training symbols;

[0048] A second transceiver, which is part of the wireless control module, receives a signal on a second frequency band from a signal conversion device, wherein the conversion circuit of the signal conversion device converts a signal on the first frequency band into a signal on the second frequency band.

[0049] The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine changes in the values ​​of one or more channel state information (CSI) parameters; and

[0050] The presence of one or more occupants in the vehicle's internal compartment area is determined based on changes in one or more CSI parameters.

[0051] Option 16. An occupant detection system for the interior compartment area of ​​a vehicle, the occupant detection system comprising:

[0052] One or more signal conversion devices, including conversion circuitry, wherein the conversion circuitry of each of the one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter, a mixer and a local oscillator, and a second bandpass filter; and

[0053] A wireless control module, including a multi-band transceiver having two or more transceivers, wherein the wireless control module executes instructions to:

[0054] A first transceiver continuously transmits signals in a first frequency band, wherein the signals include data packets containing original training symbols;

[0055] The second transceiver receives a signal in the second frequency band from the signal conversion device, wherein the conversion circuit of the signal conversion device converts the signal in the first frequency band into a signal in the second frequency band;

[0056] The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine changes in the values ​​of one or more channel state information (CSI) parameters; and

[0057] The presence of one or more occupants in the vehicle's internal compartment area is determined based on changes in one or more CSI parameters.

[0058] Option 17. The occupant detection system according to Option 16, wherein the combined low-noise amplifier and bandpass filter includes a bandpass filter, the bandpass filter including a passband with a center frequency at a first bandpass frequency.

[0059] Option 18. The occupant detection system according to Option 16, wherein the mixer and the local oscillator convert the signal in the first frequency band into the signal in the second frequency band.

[0060] Option 19. The occupant detection system according to Option 16, wherein the bandpass filter has a passband with a center frequency equal to a second bandpass frequency.

[0061] Option 20. The occupant detection system according to Option 16, wherein the wireless control module supports a wireless communication protocol for performing CSI estimation using training symbols.

[0062] Further areas of application will become apparent from the description provided herein. It should be understood that the descriptions and specific examples are intended for illustrative purposes only and are not intended to limit the scope of this disclosure. Attached Figure Description

[0063] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of this disclosure in any way.

[0064] Figure 1 This is a schematic diagram of an occupant sensing system for the interior compartment of a vehicle, disclosed according to an exemplary embodiment, the occupant sensing system including a wireless control module and one or more signal conversion devices;

[0065] Figure 2 This is according to an exemplary embodiment. Figure 1 A schematic diagram of one of the signal conversion devices shown;

[0066] Figure 3 This is a process flowchart illustrating a method for detecting occupants in an interior compartment area of ​​a vehicle according to an exemplary embodiment;

[0067] Figure 4A An alternative embodiment of an occupant detection system according to an exemplary embodiment is shown, the occupant detection system including a plurality of signal conversion devices, each of which is installed on a different seat in an interior compartment area of ​​the vehicle;

[0068] Figure 4B This illustrates the allocation according to an exemplary embodiment. Figure 4A A graph showing the unique subcarrier frequency of each signal conversion device shown;

[0069] Figure 5 An exemplary embodiment is shown. Figure 2 Alternative embodiments of the signal conversion device shown; and

[0070] Figure 6 This is a flowchart illustrating a method for performing coarse-grain localization to determine the unique location of a detected presence within an interior compartment area of ​​a vehicle, according to an exemplary embodiment. Detailed Implementation

[0071] The following description is exemplary in nature and is not intended to limit this disclosure, application, or use.

[0072] refer to Figure 1 An exemplary occupant detection system 12 is shown for detecting the presence of one or more occupants within an interior compartment area 14 of a vehicle 10. The vehicle 10 can be any type of vehicle, such as, but not limited to, a sedan, truck, SUV, van, or motorhome. The occupant detection system 12 includes a wireless control module 20 that wirelessly communicates with one or more signal conversion devices 22 disposed within the interior compartment area 14 of the vehicle 10. As explained below, the one or more signal conversion devices 22 may be placed in a strategic position within the interior compartment area 14 of the vehicle 10. The wireless control module 20 includes a multi-band transceiver 26 having two or more transceivers 24, each transceiver 24 supporting a unique frequency band. It should be understood that the wireless control module 20 supports any wireless communication protocol that uses training symbols to perform channel state information (CSI) estimation. It should be understood that the receiving transceivers 24 of the wireless control module 20 are assumed to know in advance what will be transmitted, and the training symbols also include pilot symbols. For example, in a non-limiting embodiment, the wireless control module 20 supports wireless communication according to one or more of the Institute of Electrical and Electronics Engineers (IEEE) 802.11 Wireless Local Area Network (WLAN) related standards.

[0073] although Figure 1 An occupant detection system 12 is shown for detecting occupants within the interior compartment area 14 of a vehicle 10; however, it should be understood that the occupant detection system 12 is not limited to vehicles. In fact, the disclosed occupant detection system 12 can be used in any other application to detect the presence of occupants in enclosed spaces. In other words, in another embodiment, Figure 1 The interior compartment area 14 shown is an enclosed space, such as a room that is part of a building. In one example, the occupant detection system 12 can be used to detect the presence of an individual in a specific room of a building, such as a bedroom in a residence or a conference room in an office building.

[0074] exist Figure 1 In the example shown, the wireless control module 20 includes two transceivers 24A and 24B; however, it should be understood that... Figure 1 This is merely an example, and the wireless control module 20 may also include more than two transceivers 24. Specifically, Figure 1 A first transceiver 24A configured to transmit and receive signals on a first frequency band B1 and a second transceiver 24B configured to transmit and receive signals on a second frequency band B2 are shown. In one example, where the wireless control module 20 supports wireless communication according to the IEEE 802.11 WLAN standard, the first transceiver 24A transmits and receives signals on a 2.4 GHz band, and the second transceiver 24B transmits and receives signals on a 5 GHz band. As explained below, one of the transceivers 24 of the wireless control module 20 transmits signals that are up-converted or down-converted from one frequency band to another by one or more signal conversion devices 22, wherein the up-converted or down-converted signal is received by another transceiver 24, and the wireless control module 20 executes instructions to determine the presence of an individual within the interior compartment area 14 based on CSI estimation. Also as explained below, in an embodiment, the occupant detection system 12 determines the location of a detected presence within the vehicle 10 based on coarse-grained localization. The detected location indicates the seat position within the interior compartment area 14 of vehicle 10.

[0075] exist Figure 1 In the example shown, the wireless control module 20 includes all the transceivers 24. Therefore, the vehicle 10 includes only one wireless control module 20, resulting in a reduction in cost. However, in another embodiment, one or more transceivers 24 may be located within the interior cabin area 14 of the vehicle 10 or on another control module within wireless proximity. For example, in one embodiment, one or more transceivers 24 may be located on a smartphone within the interior cabin area 14 of the vehicle 10.

[0076] The interior compartment area 14 of vehicle 10 includes the cargo area of ​​vehicle 10. Some examples of cargo areas include, but are not limited to, the trunk of a sedan or the tailgate of a sports utility vehicle. Therefore, in this embodiment, the occupant detection system 12 can also detect occupants in the cargo area of ​​vehicle 10. It is understood that the occupant detection system 12 can detect the presence of individuals (i.e., people) and animals (such as, for example, pets) placed in the cargo area of ​​vehicle 10. Furthermore, it is understood that, in this embodiment, the interior compartment area 14 of vehicle 10 includes an area immediately adjacent to the interior compartment area 14, which is within the wireless sensing proximity of the wireless control module 20. Therefore, the signal conversion device 22 can be placed immediately adjacent to the interior compartment area 14 of vehicle 10, but still wirelessly communicate with the wireless control module 20.

[0077] Figure 2 yes Figure 1 A schematic diagram of one of the signal conversion devices 22 shown. (Reference) Figure 1 and Figure 2 Each signal conversion device 22 includes a conversion circuit 40 for up-converting or down-converting a signal received from one of the transceivers 24 from one frequency band to another. Specifically, in Figure 2 In the example shown, the conversion circuit 40 of the signal conversion device 22 electronically communicates with the receiving antenna 42, the transmitting antenna 44, and the power supply 46. The bandwidth of the receiving antenna 42 is the same as the first bandwidth B1 of the signal transmitted from the first transceiver 24A of the multi-band transceiver 26 of the wireless control module 20. Similarly, the bandwidth of the transmitting antenna 44 is the same as the second bandwidth B2 of the signal received by the second transceiver 24B of the multi-band transceiver 26 of the wireless control module 20.

[0078] It should be understood that, in embodiments, the signal conversion device 22 may comprise only analog circuitry, and is therefore less costly than other devices that include components such as processors. However, it should be understood that digital components may be used in some implementations. It should also be understood that the signal conversion device 22 of the wireless control module 20 is used for bandwidth conversion, and signals transmitted by the first transceiver 24A, propagated to one of the signal conversion devices 22, are up-converted or down-converted, and then sent back to the same wireless control module 20 at the second transceiver 24B. In one embodiment, the signal conversion device 22 is a portable device, such as an radio frequency (RF) tag that can be carried by a person or attached to an item such as a child car seat or stroller. Figure 4A and Figure 4B In the embodiment shown, the signal conversion device 22 may also be integrated into the covering of one or more seats 100 of the vehicle 10. For example, if one or more seats 100 are covered with fabric, the signal conversion device 22 may be woven into the fabric of the respective seat 100.

[0079] Power source 46 is any device that provides power to the conversion circuit 40 of the signal conversion device 22; for example, the power source may be a battery or an energy harvesting device. In embodiments, the energy harvesting device captures energy from sources such as, but not limited to, radio frequency, light, vibration, and heat, and converts the energy into electricity. It should be understood that, in one embodiment, the conversion circuit 40 of the signal conversion device 22 is a low-power device requiring a relatively small amount of electrical power in the order of a few hundred milliwatts.

[0080] Continue to refer to Figure 1 and Figure 2The conversion circuit 40 of the signal conversion device 22 includes a combined low-noise amplifier (LNA+BPF) 50 with a bandpass filter, a mixer 54, a second bandpass filter 56, a local oscillator 58, and an RF amplifier 60. The combined low-noise amplifier 50 with a bandpass filter includes a low-noise amplifier 50A and a bandpass filter 50B. The first transceiver 24A of the radio control module 20 continuously transmits signals in a first frequency band B1, wherein the signals include data packets containing training symbols. As explained below, the conversion circuit 40 of the signal conversion device 22 converts the signals received from the first transceiver 24A in the first frequency band B1 into signals in a second frequency band B2. The signals in the second frequency band B2 are transmitted to the second transceiver 24B of the radio control module 20 via the transmitting antenna 44. The radio control module 20 performs CSI estimation by comparing the original training symbols included in the signals in the first frequency band B1 with the training symbols included in the received signals in the second frequency band B2 to determine the presence of one or more occupants in the internal compartment area 14 based on the CSI estimation. It should be understood that, despite Figure 2 The diagram shows the first transceiver 24A communicating wirelessly with the receiving antenna 42, and the second transceiver 24B communicating wirelessly with the transmitting antenna 44; however, it should be understood that... Figure 2 This is merely an example, and alternatively, the first transceiver 24A may communicate wirelessly with the transmitting antenna 44, and the second transceiver 24B may communicate wirelessly with the receiving antenna 42.

[0081] A combined low-noise amplifier 50 with a bandpass filter receives a signal in a first frequency band B1 from a receiving antenna 42, and the low-noise amplifier 50A amplifies the signal in the first frequency band B1 to improve signal quality without introducing additional noise. A bandpass filter 50B includes a passband having a center frequency at the first bandpass frequency B1. A mixer 54 and a local oscillator 58 convert the signal in the first frequency band B1 to a signal in a second frequency band B2. For example, in one embodiment, the mixer 54 and the local oscillator 58 can upconvert a signal in the 2.4 GHz band to a signal in the 5 GHz band. A second bandpass filter 56 includes a second passband having a center frequency equal to the second bandpass frequency B2. The second bandpass filter 56 receives the signal in the second frequency band B2 from the mixer 54 and removes any irrelevant frequencies. An RF amplifier 60 receives the signal in the second frequency band B2 and increases the power of the signal in the second frequency band B2. In one embodiment, the RF amplifier increases the power of a signal in the second frequency band B2 from a low-power signal to a higher-power signal before the signal is transmitted from the transmitting antenna 44 to the second transceiver 24B.

[0082] refer to Figure 1 and Figure 2The wireless control module 20 determines the presence of one or more occupants within the interior compartment area 14 of the vehicle 10 by comparing the original training symbols included in the signal on the first frequency band B1 with the training symbols included in the signal on the second frequency band B2 to determine one or more variations in the values ​​of one or more CSI parameters based on a signal processing method. Specifically, the variations in the values ​​of the CSI parameters are relative to the time domain, frequency domain, or spatial domain, and the CSI parameters include, but are not limited to, amplitude, phase, and signal delay. As an example of variations in the CSI parameters, the magnitude of the vector difference between the CSI parameters can be determined. For example, in one embodiment, the wireless control module 20 determines the presence of one or more occupants based on amplitude attenuation in the time domain. It should be understood that various signal processing methods based on CSI estimation exist for determining the presence of one or more occupants within the interior compartment area 14 of the vehicle 10. For example, in one embodiment, the wireless control module 20 employs a time-series analysis of all CSI magnitudes corresponding to all subcarrier frequencies based on principal component analysis (PCA).

[0083] Figure 3 This is a process flowchart illustrating an exemplary method 200 for detecting the presence of occupants within an interior compartment area 14 of a vehicle 10 using an occupant detection system 12. (See reference...) Figures 1-3 Method 200 can begin at block 202. In block 202, the first transceiver 24A of the wireless control module 20 continuously transmits signals on the first frequency band B1, wherein the signals include data packets containing the original training symbols. Method 200 can then proceed to block 204.

[0084] In block 204, one or more of the signal conversion devices 22 receive signals on the first frequency band B1 via the receiving antenna 42. Method 200 can then proceed to block 206.

[0085] In block 206, the conversion circuit 40 of the signal conversion device 22 converts the signal received from the first transceiver 24A on the first frequency band B1 into a signal on the second frequency band B2. Method 200 can then proceed to block 208.

[0086] In block 208, the signal on the second frequency band B2 is transmitted to the second transceiver 24B of the wireless control module 20 via the transmitting antenna 44 of the signal conversion device 22. Then method 200 can proceed to block 210.

[0087] In block 210, the wireless control module 20 compares the original training symbols from the signal on the first frequency band B1 with the training symbols from the signal on the second frequency band B2 to determine one or more variations in the values ​​of one or more CSI parameters based on a signal processing method. As mentioned above, variations in the CSI parameters include variations in the time domain, frequency domain, or spatial domain, and the CSI parameters include, but are not limited to, amplitude, phase, and signal delay. Method 200 can then proceed to block 212.

[0088] In block 212, the wireless control module 20 determines the presence of one or more occupants within the interior compartment area 14 of the vehicle 10 based on changes in the values ​​of one or more CSI parameters. Method 200 can then terminate or return to block 202.

[0089] Overall reference Figures 1-3 The disclosed occupant detection system offers various technical effects and benefits. Specifically, the disclosed occupant detection system provides a low-cost method for detecting the presence of occupants within the interior compartment of a vehicle using wireless sensing technology. Current methods for detecting the presence of occupants in a vehicle require two control modules, and since most vehicles currently only require a single control module, this can introduce additional costs. In contrast, the disclosed occupant detection system requires only a single control module that communicates with one or more signal conversion devices, which in turn reduces the overall cost and complexity of the occupant detection system.

[0090] Figure 4A This is a schematic diagram illustrating an alternative embodiment of the disclosed occupant detection system 112, which includes a plurality of signal conversion devices 122, each signal conversion device 122 being assigned to a unique location within an interior compartment area 114 of the vehicle 110. In such... Figure 4A In the illustrated embodiment, the unique location is the seating position within the interior compartment area 114 of the vehicle 10. For example, the seating position may refer to the driver's seat, passenger seat, rear seat behind the driver, middle seat, rear seat behind the passenger, third-row seat behind the driver, and third-row seat behind the passenger. Figure 4A In the example shown, vehicle 110 includes five seats 100. However, it should be understood that... Figure 4A This is merely illustrative in essence, and the unique location within vehicle 10 is not limited to the seating position. Alternatively, the unique location within vehicle 110 could represent the cargo area in a sports utility vehicle. Furthermore, although... Figure 4A Five seats 100 are shown, but it should be understood that vehicle 10 may also include fewer or more seats. Specifically, vehicle 110 includes the following seating positions: driver's seat 100A, passenger seat 100B, and three rear passenger seats 100C, 100D, and 100E.

[0091] Figure 4A Signal conversion devices 122A assigned to driver's seat 100A, 122B assigned to passenger seat 110B, and 122C, 122D, and 122E assigned to rear passenger seats 100C, 100D, and 100E, respectively, are also shown. In one embodiment, signal conversion device 122 is woven into the fabric of the seat 100 of vehicle 110. As explained below, in one embodiment, occupant detection system 112 determines the unique location of a detected presence within vehicle 110 based on coarse-grained positioning. Figure 4A In the embodiment shown, the unique location of the detected presence indicates the seat position within the interior compartment area 114 of the vehicle 110. For example, if the driver's seat 100A is occupied, the occupant detection system 112 will indicate that the detected presence is at the driver's seat 100A.

[0092] Figure 4B To show the allocation Figure 4A A graph showing the unique subcarrier frequency SC of each signal conversion device 122 in the diagram, where the x-axis represents frequency and the y-axis represents CSI parameters such as amplitude. Figure 5 yes Figure 4A A schematic diagram of one of the signal conversion devices 122 shown. (Reference) Figure 4A , Figure 4B and Figure 5 Each signal conversion device 122 is positioned within a corresponding seat 100 such that when the corresponding seat is occupied, the signal path between the first transceiver 124A of the wireless control module 120 and one or both of the receiving antenna 142 or transmitting antenna 144 of the corresponding signal conversion device 122 is blocked, such as by an individual located in the seat 100.

[0093] The conversion circuit 140 of each signal conversion device 122 (see Figure 5 A unique subcarrier frequency SC is assigned, which is part of the entire spectrum of the second frequency band B2. Therefore, when the corresponding seat 100 located in the internal compartment area 114 is occupied, the corresponding receiving antenna 142 from the first transceiver 124A to the radio control module 20 ( Figure 5 The direct signal path of the driver's seat 100 is blocked, and therefore the only frequency range allocated to the corresponding seat 100 is attenuated from the entire spectrum of the second bandwidth frequency B2. For example, if the driver's seat 100A is occupied, the only subcarrier frequency SC allocated to the driver's seat 100A is... A The frequency is attenuated across the entire spectrum of the second frequency band B2. Similarly, if passenger seat 100B is occupied, the unique subcarrier frequency SC allocated to passenger seat 100B is...B Attenuation occurs across the entire spectrum of the second frequency band B2. If one of the rear passenger seats 100C, 100D, or 100E is occupied, the unique subcarrier frequency SC allocated to the corresponding rear passenger seat 100C, 100D, or 100E is used. C SC D SC E It is attenuated throughout the entire spectrum of the second frequency band B2.

[0094] refer to Figure 5 The conversion circuit 140 of the signal conversion device 122 includes a power supply 146, a combined low-noise amplifier (LNA+BPF) 150 with a bandpass filter, a mixer 154, a subcarrier bandpass filter 156, a local oscillator 158, and an RF amplifier 160. The combined low-noise amplifier 150 with a bandpass filter includes a low-noise amplifier 150A and a bandpass filter 150B. Figure 5 The conversion circuit 140 shown is similar to Figure 2 The conversion circuit 40 shown includes a subcarrier passband equal to the unique subcarrier frequency SC assigned to the corresponding signal conversion device 122, except that the subcarrier bandpass filter 156 includes a subcarrier passband equal to the unique subcarrier frequency SC assigned to the signal conversion device 122A. For example, the subcarrier bandpass filter 156 for signal conversion device 122A includes a subcarrier passband equal to the unique subcarrier frequency SC assigned to the signal conversion device 122A of driver's seat 100A. A Equal subcarrier passband. Similarly, the subcarrier bandpass filter 156 for the signal conversion device 122B includes the same subcarrier frequency SC as the unique subcarrier frequency SC allocated to the signal conversion device 122B for the passenger seat 100B. B Equal subcarrier passbands.

[0095] The wireless control module 120 determines the unique location of a detected presence within the interior compartment area 114 of the vehicle 110 based on coarse-grained positioning, wherein the location of the detected presence indicates a seat position within the interior compartment area 114 of the vehicle 110. Specifically, the wireless control module 120 determines the detected presence within the interior compartment area 114 of the vehicle 110 based on the absence of one or more unique subcarrier frequencies SC, which are part of the entire spectrum of the second frequency band B2. In response to determining that a presence is detected within the interior compartment area 114 of the vehicle 110, the wireless control module 120 determines the unique location of the detected presence within the interior compartment area 114 by associating the missing subcarrier frequencies, which are part of the total spectrum of the second frequency band B2, with the corresponding unique location within the interior compartment area 114 of the vehicle 110. For example, referring to 4A and 4B, if the missing subcarrier frequency is the unique subcarrier frequency SC assigned to the signal conversion device 122A of the driver's seat 100A... AThen the wireless control module 20 determines that the only location detected is the driver's seat 100A.

[0096] The conversion circuit 140 of each signal conversion device 122 (see Figure 5 A unique subcarrier frequency SC is assigned to each seat 100, which is part of the entire spectrum of the second band B2. Therefore, when a corresponding seat 100 located in the interior compartment area 114 is occupied, the direct signal path from the first transceiver 124A to the corresponding receiving antenna 142 or transmitting antenna 144 of the radio control module 20 is blocked, and thus the unique subcarrier frequency SC assigned to the corresponding seat 100 is attenuated from the entire spectrum of the second bandwidth frequency B2.

[0097] Figure 6 This is a flowchart illustrating an exemplary method 300 for detecting the presence of occupants in an interior compartment area 14 of a vehicle 10 using an occupant detection system 12. (See reference...) Figure 4A , Figure 4B , Figure 5 and Figure 6 Method 300 can begin at block 302. In block 302, the first transceiver 124A of the wireless control module 120 continuously transmits signals on the first frequency band B1. Method 300 can then proceed to decision block 304.

[0098] In decision block 304, if an occupant is present in one or more seats 100 within the interior compartment area 114 of vehicle 10, one or more of the plurality of signal conversion devices 122 do not receive signals on the first frequency band B1 via the corresponding receiving antenna 142, and method 300 may then proceed to block 306. If no occupant is present in any of the seats 100 within the interior compartment area 14 of vehicle 10, the method may proceed to block 306. In block 306, the radio control module 20 determines that each unique subcarrier frequency SC assigned to the corresponding seat 100 exists across the entire spectrum of the second bandwidth frequency B2, and therefore no presence is detected. Method 300 may terminate.

[0099] In block 308, the conversion circuit 140 of the signal conversion device 122, corresponding to an unoccupied location within the interior compartment area 114 of the vehicle 110, converts a signal received from the first transceiver 24A on a first frequency band B1 into a signal on a second frequency band B2. See details. Figure 5 The subcarrier bandpass filter 156 of the conversion circuit 140 corresponding to the unoccupied seat 100 in the interior compartment area 114 of vehicle 110 allows a frequency equal to the unique subcarrier frequency SC assigned to the corresponding signal conversion device 122 to pass through. Then, method 300 can proceed to block 310.

[0100] In block 310, the unique subcarrier frequency SC of the second frequency band B2 assigned to the corresponding signal conversion device 122 is transmitted to the second transceiver 124B of the wireless control module 120 via the transmitting antenna 144 of the corresponding signal conversion device 22. Then, method 200 can proceed to block 312.

[0101] In block 312, the wireless control module 120 determines the presence of a detected signal within the interior compartment area 114 of the vehicle 10 based on the absence of one or more unique subcarrier frequencies SC that are part of the entire spectrum of the second frequency band B2. Method 300 can then proceed to block 314.

[0102] In block 314, in response to determining that a presence was detected within the interior compartment area 114 of the vehicle 110, the wireless control module 120 determines the unique location of the detected presence within the interior compartment area 114 by associating a missing subcarrier frequency, which is part of the total spectrum of the second frequency band B2, with a corresponding unique location within the interior compartment area 114 of the vehicle 10. Method 300 can then terminate.

[0103] Generally refer to 4- Figure 6 The disclosed occupant detection system offers various technical effects and benefits by providing a low-cost method for determining the location of detected presences in a vehicle. In an embodiment, the detected presence can be the seat position of an occupant in the vehicle. Current systems available for determining seat position, such as weight sensors, significantly increase the cost of the vehicle. In contrast, the disclosed occupant detection system requires only a single control module that communicates with one or more signal conversion devices, which in turn reduces the overall cost and complexity of the occupant detection system.

[0104] A controller can refer to or a subset of the following: electronic circuitry, combinational logic circuitry, field-programmable gate arrays (FPGAs), processors (shared, dedicated, or grouped) that execute code, or combinations thereof, such as in a system-on-a-chip. Alternatively, the controller can be microprocessor-based, such as a computer having at least one processor, memory (RAM and / or ROM), and associated input and output buses. The processor can operate under the control of an operating system residing in memory. The operating system can manage computer resources so that computer program code implemented as one or more computer software applications (such as applications residing in memory) can have instructions that are executed by the processor. In alternative embodiments, the processor can directly execute the application program, in which case the operating system may be omitted.

[0105] The description in this disclosure is merely exemplary in nature, and variations thereof without departing from the spirit and scope of this disclosure are intended to fall within its scope. Such variations should not be considered as departing from the spirit and scope of this disclosure.

Claims

1. An occupant detection system for the interior compartment area of ​​a vehicle, the occupant detection system comprising: One or more signal conversion devices, including conversion circuitry; as well as A wireless control module, comprising a multi-band transceiver having two or more transceivers, wherein the wireless control module executes instructions to: A first transceiver continuously transmits signals in a first frequency band, wherein the signals include data packets containing original training symbols; The signal in the second frequency band is received from the signal conversion device via the second transceiver, wherein the conversion circuit of the signal conversion device converts the signal in the first frequency band into the signal in the second frequency band; The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine the changes in the values ​​of one or more channel state information (CSI) parameters; as well as The presence of one or more occupants in the vehicle's internal compartment area is determined based on changes in one or more CSI parameters.

2. The occupant detection system of claim 1, wherein each of the one or more signal conversion devices includes a power source that supplies power to the conversion circuit.

3. The occupant detection system according to claim 2, wherein the power source is a battery or an energy harvesting device.

4. The occupant detection system of claim 3, wherein the energy harvesting device captures energy from one or more of the following: radio frequency, light, vibration, and heat.

5. The occupant detection system of claim 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter.

6. The occupant detection system of claim 5, wherein the bandpass filter comprises a passband having a center frequency at a first bandpass frequency.

7. The occupant detection system of claim 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a mixer and a local oscillator for converting a signal in the first frequency band into a signal in the second frequency band.

8. The occupant detection system of claim 1, wherein the conversion circuit of each of the one or more signal conversion devices includes a bandpass filter having a passband with a center frequency equal to a second bandpass frequency.

9. The occupant detection system according to claim 1, wherein the wireless control module supports a wireless communication protocol, the wireless communication protocol employing training symbols to perform CSI estimation.

10. The occupant detection system of claim 1, wherein the one or more signal conversion devices are radio frequency (RF) tags.

11. The occupant detection system of claim 1, wherein the interior compartment area of ​​the vehicle includes the cargo area of ​​the vehicle.

12. The occupant detection system of claim 1, wherein the interior compartment area of ​​the vehicle includes a region immediately outside the interior compartment area, the region being within the wireless sensing proximity of the wireless control module.

13. The occupant detection system of claim 1, wherein the CSI parameters include amplitude, phase, and signal delay.

14. The occupant detection system according to claim 1 further includes a plurality of signal conversion devices, each of which is assigned to a corresponding seat in the interior compartment area of ​​the vehicle.

15. A method for detecting the presence of occupants in an interior compartment area of ​​a vehicle using an occupant detection system, the method comprising: A first transceiver, which is part of a wireless control module, continuously transmits signals on a first frequency band, wherein the signals include data packets containing original training symbols; A second transceiver, which is part of the wireless control module, receives a signal on a second frequency band from a signal conversion device, wherein the conversion circuit of the signal conversion device converts a signal on the first frequency band into a signal on the second frequency band. The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine the changes in the values ​​of one or more channel state information (CSI) parameters; as well as The presence of one or more occupants in the vehicle's internal compartment area is determined based on changes in one or more CSI parameters.

16. An occupant detection system for an interior compartment area of ​​a vehicle, the occupant detection system comprising: One or more signal conversion devices, including conversion circuitry, wherein the conversion circuitry of each of the one or more signal conversion devices includes a combined low-noise amplifier with a bandpass filter, a mixer and a local oscillator, and a second bandpass filter; as well as A wireless control module, including a multi-band transceiver having two or more transceivers, wherein the wireless control module executes instructions to: A first transceiver continuously transmits signals in a first frequency band, wherein the signals include data packets containing original training symbols; The second transceiver receives a signal in the second frequency band from the signal conversion device, wherein the conversion circuit of the signal conversion device converts the signal in the first frequency band into a signal in the second frequency band; The original training symbols from the signal in the first frequency band are compared with the training symbols from the signal in the second frequency band to determine the changes in the values ​​of one or more channel state information (CSI) parameters; as well as The presence of one or more occupants in the vehicle's internal compartment area is determined based on changes in one or more CSI parameters.

17. The occupant detection system of claim 16, wherein, The bandpass filter includes a passband with a center frequency at a first pass frequency.

18. The occupant detection system according to claim 16, wherein, The mixer and local oscillator convert the signal in the first frequency band into a signal in the second frequency band.

19. The occupant detection system according to claim 16, wherein, The bandpass filter has a passband with a center frequency equal to the second pass frequency.

20. The occupant detection system according to claim 16, wherein, The wireless control module supports wireless communication protocols that use training symbols to perform CSI estimation.

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