JP7761144B2 - Wireless sensing system, wireless sensing method, and measurement request device - Google Patents

Description

This disclosure relates to a wireless sensing system, a wireless sensing method, and a wireless sensing device, and in particular to a wireless sensing system, a wireless sensing method, and a wireless sensing device suitable for use with a multi-link device.

The following non-patent document 1 discloses a wireless sensing technology that uses propagation channel state information (CSI). In this technology, a measurement signal is transmitted wirelessly from a measurement requesting device such as an access point (AP) to a measuring device such as a station (STA). The measurement signal reflects the state of the propagation path as it reaches the measuring device. The measuring device extracts propagation channel state information from the received measurement signal and returns a communication signal containing that information to the measurement requesting device.

The measurement requesting device senses the propagation path based on the propagation channel state information contained in the communication signal. This technology makes it possible to sense, for example, the position of objects or people on the propagation path between the measurement requesting device and the measuring device, or the open/close status of a door.

The following non-patent document 2 discloses the standard for wireless LANs defined by IEEE 802.11be. Under the 802.11be standard, APs and STAs are equipped with Multi-Link Device (MLD) functionality. A device with MLD functionality has multiple wireless functions corresponding to different frequency bands within a single housing. Each wireless function for each frequency band can establish its own transmission path, enabling high-speed, highly reliable communications. Multi-link transmission also includes a synchronous mode in which multiple frequency bands are synchronized for transmission and reception, and an asynchronous mode in which each frequency band is independently used for transmission and reception.

Yang, Zheng, Zimu Zhou, and Yunhao Liu. "From RSSI to CSI: Indoor Localization via Channel Response." ACM Computing Surveys (CSUR) Vol. 46.2, Article 25, November 2013 E. Khorov, I. Levitsky and I. F. Akyildiz, "Current Status and Directions of IEEE 802.11be, the Future Wi-Fi 7," in IEEE Access, vol. 8, pp. 88664-88688, May 8, 2020

Under the IEEE 802.11be standard, it is conceivable to implement the wireless sensing described in Non-Patent Document 1 using the MLD described in Non-Patent Document 2. If a device with MLD functionality is available, the accuracy of wireless sensing can be improved by detecting CSI in multiple frequency bands and integrating them. Furthermore, by simultaneously performing sensing in all multiple frequency bands, multiple CSI can be obtained simultaneously, minimizing the time required to perform wireless sensing. For this reason, when implementing wireless sensing using MLD, it is desirable to use a synchronous mode in which all frequency bands are operated simultaneously.

However, the multiple wireless functions that make up an MLD may be placed in a state where they cannot begin transmission due to restrictions, for example, from the NAV (Network Allocating Vector) issued by other wireless devices. In other words, if another wireless device occupies a specific frequency band and transmits a NAV indicating the remaining time of that occupancy, the MLD that receives this notification will be unable to begin transmission in that frequency band until the NAV reaches zero.

If some of the multiple wireless functions that make up an MLD are unable to start transmission, even if a command to transmit simultaneously is issued to all wireless functions, some of those wireless functions will not operate. In such a situation, resources such as antennas assigned to frequency bands that cannot be transmitted will be wasted and wireless sensing will be carried out using only the few frequency bands that can be transmitted. In this case, the accuracy of sensing is likely to decrease compared to when wireless sensing is carried out using all frequency bands.

The present disclosure has been made in consideration of the above-mentioned problems, and its first objective is to provide a wireless sensing system that can prevent sensing accuracy from decreasing significantly compared to normal conditions when a multi-link device is performing wireless sensing in synchronous mode, even if some frequency bands are unable to transmit.

A second objective of the present disclosure is to provide a wireless sensing method that prevents sensing accuracy from decreasing significantly compared to normal conditions when a multi-link device performs wireless sensing in synchronous mode, even if some frequency bands are in a state where transmission is not possible.

A third objective of the present disclosure is to provide a measurement request device that can prevent sensing accuracy from decreasing significantly compared to normal conditions when a multi-link device is made to perform wireless sensing in synchronous mode, even if some frequency bands are unable to transmit.

In order to achieve the above object, a first aspect is a wireless sensing system including a measurement requesting device having a plurality of wireless functions corresponding to different frequency bands in a single housing, and a measuring device having a plurality of wireless functions corresponding to different frequency bands in a single housing,
a process in which the measurement requesting device transmits measurement signals in a plurality of frequency bands;
a process in which the measurement device receives the measurement signals in a plurality of frequency bands and extracts propagation channel state information for each frequency band;
and calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information for each frequency band,
It is desirable that at least one of the measurement requesting device and the measuring device is configured to, when a frequency band that cannot be transmitted exists when the execution of the wireless sensing is requested, execute a process of setting the wireless communication hardware resources allocated to that frequency band as additional usage resources to be used for transmitting overlapping signals in a frequency band that can be transmitted.

A second aspect is a wireless sensing method using a measurement requesting device having a plurality of wireless functions corresponding to different frequency bands in one housing, and a measuring device having a plurality of wireless functions corresponding to different frequency bands in one housing,
the measurement requesting device transmitting measurement signals in a plurality of frequency bands;
the measurement device receiving the measurement signals in a plurality of frequency bands and extracting propagation channel state information for each frequency band;
calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information for each frequency band;
When a frequency band that cannot be transmitted exists when the execution of the wireless sensing is requested, at least one of the measurement requesting device and the measuring device sets a wireless communication hardware resource that has been allocated to the frequency band as an additional use resource to be used for transmitting overlapping signals in a frequency band that can be transmitted;
It is desirable to include:

A third aspect is a measurement requesting device that realizes a wireless sensing function based on the results of information communication with a measuring device having a plurality of wireless functions corresponding to different frequency bands in one housing,
It has multiple wireless functions corresponding to different frequency bands in one housing,
transmitting measurement signals in multiple frequency bands to the measurement device;
receiving a notification signal transmitted by the measurement device for each frequency band, the notification signal including propagation channel state information extracted from the measurement signal for each frequency band;
calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information extracted from the notification signal for each frequency band;
a process of setting, when a frequency band that cannot be transmitted exists when the execution of the wireless sensing is requested, the wireless communication hardware resource that has been allocated to the frequency band in question as an additional use resource to be used for transmitting overlapping signals in a frequency band that can be transmitted;
Preferably, the system is configured to execute the following:

According to the first to third aspects, when a multi-link device performs wireless sensing in synchronous mode, if some frequency bands are unavailable for transmission, the communication resources corresponding to those frequency bands can be utilized for signal transmission in other frequency bands. As a result, signal transmission over multiple links is realized in the other frequency bands, improving sensing accuracy compared to when signal transmission is performed over a single link. Therefore, according to this aspect, even if some frequency bands are unavailable for transmission, it is possible to avoid a significant decrease in sensing accuracy compared to normal.

FIG. 1 is a diagram illustrating a configuration of a wireless sensing system according to a first embodiment of the present disclosure. 2 is a block diagram for explaining the configuration of a measurement request device included in the wireless sensing system shown in FIG. 1 . FIG. FIG. 2 is a block diagram for explaining the configuration of a measurement device included in the wireless sensing system shown in FIG. 1 . 3 is a flowchart for explaining the flow of processing executed in the measurement request device shown in FIG. 2 . 3 is a flowchart illustrating the flow of processing executed in the measurement device shown in FIG. 2 .

Embodiment 1.
[Configuration of First Embodiment]
1 is a diagram illustrating the configuration of a wireless sensing system according to a first embodiment of the present disclosure. As shown in FIG. 1, the wireless sensing system according to this embodiment includes a measurement request device 10 and a measurement device 20. Both the measurement request device 10 and the measurement device 20 have a multi-link device (MLD) function that complies with the IEEE 802.11be standard.

The measurement request device 10 is equipped with multiple access points (APs). In this embodiment, the measurement request device 10 is equipped with AP1, AP2, and AP3. AP1, AP2, and AP3 each support a different frequency band. Here, it is assumed that AP1, AP2, and AP3 support the frequency bands f1, f2, and f3, respectively. The measurement request device 10 also has three antenna units 12, 14, and 16.

Antenna units 12, 14, and 16 are all connected to three APs, AP1, AP2, and AP3, via a switching mechanism. For example, antenna unit 12 is normally connected to AP1 and is used to send and receive signals in frequency band f1. Then, in response to a command, antenna unit 12 can be connected to AP2 or AP3 and used to send and receive signals in frequency band f2 or frequency band f3. The same is true for antenna units 14 and 16.

The measurement device 20 is equipped with multiple terminal devices (STAs). In this embodiment, the measurement device 20 is equipped with STA1, STA2, and STA3. STA1, STA2, and STA3 each correspond to a different frequency band, specifically, f1, f2, and f3, respectively. The measurement device 20 also has three antenna units 22, 24, and 26.

Similar to antenna units 12, 14, and 16 provided in measurement request device 10, antenna units 22, 24, and 26 are normally connected to STA1, STA2, or STA3, respectively, and are used to send and receive signals in frequency bands f1, f2, and f3, respectively. In response to a command, they can be connected to a different STA than normal, and send and receive signals in a different frequency band than normal.

AP1 to AP3 equipped in the measurement request device 10 can send and receive wireless signals with STA1 to STA3 equipped in the measurement device 20, respectively. The measurement request device 10 and the measurement device 20 can then perform wireless sensing of the space between them. Wireless sensing makes it possible to detect the position and activity of objects present in the sensing target space.

When a request to perform wireless sensing is made, the measurement requesting device 10 and the measuring device 20 begin communication in synchronous mode. As a result, if all of AP1 to AP3 and all of STA1 to STA3 are in a transmit-enabled state, wireless signals 30 are transmitted and received simultaneously in all frequency bands f1 to f3.

However, AP1 to AP3 and STA1 to STA3 may each be subject to transmission restrictions. For example, if another communication device using the same frequency band needs to occupy that frequency band for a certain period of time, it may notify the NAV indicating the remaining time of occupancy. A communication device that receives such a notification is required to refrain from starting transmission until the NAV reaches zero. For this reason, in the system of this embodiment, it is assumed that when a request is made to perform wireless sensing, one of AP1 to AP3 and STA1 to STA3 will be in a state where transmission is not possible.

Figure 1 shows the operation of this embodiment when one or both of AP3 and STA3 are unable to transmit when wireless sensing is requested. Specifically, AP1 and STA1 transmit and receive an f1 signal 32 in frequency band f1 via antenna units 12 and 22. AP2 and STA2 transmit and receive an f2 signal 34 in frequency band f2 via antenna units 14 and 24.

And because AP3 and STA3 are in a state where transmission is disabled, antenna units 16 and 26 are used to transmit and receive overlapping signals 36 in frequency band f2 between AP2 and STA2. In this way, when a synchronization mode of multiple frequency bands is requested, if some frequency bands are unavailable for transmission, the wireless communication system of this embodiment utilizes the hardware resources that would have covered those frequency bands for communication in other available frequency bands.

In the situation shown in Figure 1, the propagation path of the f2 signal 34 and the propagation path of the overlapping signal 36 are not strictly the same. Therefore, even if both signals are in the same frequency band f2, the influence of the path state superimposed on the f2 signal 34 and the influence of the path state superimposed on the overlapping signal 36 will not be the same. In addition, the overlapping signal 36 may have a higher reception strength than the reception strength of the f2 signal 34.

Therefore, when AP3 and STA3 are unable to transmit, by utilizing antenna units 16 and 26 to send and receive overlapping signal 36 rather than leaving them unnecessarily stopped, it becomes possible to obtain more information about the propagation path. As a result, in the wireless sensing system of this embodiment, when the measurement request device 10 and measurement device 20 perform wireless sensing in synchronous mode, it is possible to avoid a significant decrease in sensing accuracy compared to normal even when transmission is unavailable in some frequency bands.

[Details of the First Embodiment]
Hereinafter, with reference to FIGS. 2 and 3, the hardware configurations that the measurement requesting device 10 and the measuring device 20 each have to realize the above functions will be described in detail.

Figure 2 is a block diagram for explaining in detail the configuration of the measurement request device 10 in this embodiment. As shown in Figure 2, the measurement request device 10 includes a control unit 40. The control unit 40 can be realized by a dedicated hardware circuit. The control unit 40 may also include a processor and memory, and realize desired functions by having the processor execute a program stored in the memory.

The control unit 40 is equipped with a measurement request signal generation unit 42. When a request to perform wireless sensing occurs, the measurement request signal generation unit 42 generates a measurement request signal and provides that signal to the transmission units 44-1 to 44-3. The transmission unit 44-1 is equipped in AP1 and is normally used for transmission in the frequency band f1 used by AP1, but can be used for transmission in the frequency band f2 used by AP2 or the frequency band f3 used by AP3 in response to instructions from the control unit 40. The transmission units 44-2 and 44-3 are equipped in AP2 and AP3, respectively, and function in the same way as the transmission unit 44-1 in response to instructions from the control unit 40.

When the transmitters 44-1 to 44-3 receive a measurement request signal from the measurement request signal generator 42, if they are unable to transmit due to NAV compliance or other reasons, they notify the controller 40 of this fact. When the controller 40 is notified by one of the transmitters 44-1 to 44-3 that transmission is not possible, it performs processing to allocate the hardware resources allocated to that frequency band to another frequency band that is available for transmission.

For example, if the transmitter 44-3, which covers frequency band f3, is unable to transmit, the antenna 16 normally assigned to f3 is designated as an additional antenna unit to be used for transmission in the other frequency bands f1 or f2. One or both of the transmitters 44-1 and 44-2 are then instructed to transmit overlapping signals using the additional antenna unit.

Figure 2 illustrates a case where, under the above circumstances, the control unit 40 instructs the transmitting unit 44-2 to use the antenna unit 16 as the additionally used antenna unit. In this case, the measurement request signal for frequency band f1 provided by the transmitting unit 44-1 is transmitted from the antenna unit 12 as the f1 signal 32. Then, the measurement request signal for frequency band f2 provided by the transmitting unit 44-2 is transmitted from the antenna unit 14 as the f2 signal 34 and from the antenna unit 16 as the overlap signal 36.

The measurement request device 10 also has receiving units 46-1 to 46-3. Receiving unit 46-1 is provided in AP1 and corresponds to frequency band f1. Similarly, receiving units 46-2 and 46-3 are provided in AP2 and AP3, respectively, and correspond to frequency band f2 and f3, respectively. Receiving units 46-1 to 46-3 receive various signals received by antenna units 12, 14, and 16 and provide them to the control unit 40.

For example, if frequency bands f1, f2, and f3 are all available and none of antenna units 12, 14, and 16 are set as additionally usable antenna units, the f1 signal is received by receiver unit 46-1 via antenna unit 12. The f2 signal is received by receiver unit 46-2 via antenna unit 14. The f3 signal is received by receiver unit 46-3 via antenna unit 16.

In contrast, as shown in Figure 1, when antenna unit 16 is set as an additionally used antenna unit that transmits and receives the f2 overlap signal 36, antenna unit 16 receives a signal in frequency band f2 and provides that signal to receiving unit 46-2 as the overlap signal 36. In this case, receiving unit 46-2 distinguishes between the f2 signal 34 transmitted from antenna unit 14 and the overlap signal 36 transmitted from antenna unit 16. Receiving units 46-1 and 46-3 also have the function of distinguishing between signals in the same frequency band when they are transmitted from two antennas.

After transmitting the measurement request signal, the measurement request device 10 waits for a measurement preparation completion signal to be returned from the measuring device 20. The measurement preparation completion signal is provided to the control unit 40 via the antenna units 12, 14, and 16 and the receiving units 46-1 to 46-3.

The control unit 40 includes a measurement signal generation unit 48. The measurement signal generation unit 48 determines which of the frequency bands f1 to f3 is available for use, depending on which of the receiving units 46-1 to 46-3 has provided a measurement preparation completion signal. The measurement signal generation unit 48 then generates a measurement signal for performing wireless sensing and provides the measurement signal to one of the transmitting units 44-1 to 44-3 that corresponds to the available frequency band.

Like the measurement request signal, the measurement signal is transmitted in the available frequency bands using all of the antenna units 12, 14, and 16. For example, in the case shown in Figure 1, the measurement signal is transmitted from antenna unit 12 as an f1 signal 32. The measurement signal is transmitted from antenna unit 14 as an f2 signal 34. The measurement signal is then transmitted from antenna unit 16, which is set as the additionally used antenna unit, as an f2 duplicate signal 36.

After transmitting the measurement signal, the measurement request device 10 waits for a notification signal to be returned from the measurement device 20. The notification signal is provided to the control unit 40 via the antenna units 12, 14, and 16 and the receiving units 46-1 to 46-3. The control unit 40 then extracts the propagation channel state information (CSI) contained in the notification signal and, based on the results, performs location estimation or activity detection targeting the propagation path.

Figure 3 is a block diagram for explaining in detail the configuration of the measurement device 20 in this embodiment. As shown in Figure 3, the measurement device 20 has multiple receiving units 50-1 to 50-3. The receiving units 50-1 to 50-3 are provided in STA1 to STA3 and correspond to the frequency bands f1 to f3. The receiving units 50-1 to 50-3 receive signals sent from the measurement request device 10 via antenna units 22, 24, and 26 in the frequency bands assigned to them, respectively.

For example, if the measurement request device 10 transmits measurement request signals in all frequency bands f1 to f3, those signals are received by the receiving units 50-1 to 50-3 via the antenna units 22, 24, and 26. On the other hand, if only some of the receiving units 50-1 to 50-3 do not receive the measurement request signals, the measurement request device 10 recognizes that the frequency bands corresponding to those parts are unavailable.

The measurement request signals received by the receiving units 50-1 to 50-3 are provided to the control unit 52. The control unit 52 can be realized by a dedicated hardware circuit. Alternatively, the control unit 52 may include a processor and memory, and realize the desired functions by having the processor execute a program stored in the memory.

When the control unit 52 receives a measurement request signal, it begins measurement preparation for wireless sensing. Specifically, it recognizes all frequency bands for which a measurement request signal is received as usable frequency bands and sets the wireless devices corresponding to those frequency bands to synchronization mode.

The control unit 52 includes a measurement preparation completion signal generation unit 56. The measurement preparation completion signal generation unit 56 generates a measurement preparation completion signal when preparation for wireless sensing is complete. The generated measurement preparation completion signal is provided to one of the transmission units 58-1 to 58-3 that corresponds to the available frequency band.

Transmitting units 58-1 to 58-3 are provided in STA1 to STA3 and correspond to frequency bands f1 to f3. For example, if all frequency bands are available, a measurement preparation complete signal is provided to all transmitting units 58-1 to 58-3. On the other hand, if some frequency bands are unavailable, for example, if frequency band f3 is unavailable as shown in Figure 1, the measurement preparation complete signal is provided only to transmitting units 58-1 and 58-2. At this time, the control unit 52 notifies transmitting units 58-1 and 58-2 of the antenna to be set in the additional use antenna unit and the frequency band of the overlapping signal to be transmitted from the additional use antenna unit.

When transmitting units 58-1 to 58-3 receive a measurement preparation completion signal, if they are unable to transmit due to NAV restrictions or other reasons, they notify the control unit 52 of this fact. In this case, the control unit 52 recognizes the frequency band that is the subject of the notification as an unusable frequency band and instructs the transmitting unit corresponding to the usable frequency band to transmit a measurement preparation completion signal again. In this case, the control unit 52 also notifies the transmitting unit of the antenna to be set as the additional use antenna unit and the frequency band of the overlapping signal to be transmitted from the additional use antenna unit.

Figure 3 illustrates a case where, under the above circumstances, the control unit 52 instructs the transmitting unit 58-2 to use the antenna unit 26 as the additional antenna unit. In this case, the measurement readiness signal for frequency band f1 provided by the transmitting unit 58-1 is transmitted from the antenna unit 22 as the f1 signal 32. Then, the measurement readiness signal for frequency band f2 provided by the transmitting unit 58-2 is transmitted from the antenna unit 24 as the f2 signal 34 and from the antenna unit 26 as the overlap signal 36.

The measurement device 20 then waits to receive a measurement signal from the measurement request device 10. When the receiving units 50-1 to 50-3 receive the measurement signal via the antenna units 12 to 16, the signal is provided to the propagation channel measurement unit 60. The measurement signal reflects the state of the propagation path as described above. Meanwhile, the propagation channel measurement unit 60 stores the initial characteristics of the measurement signal that are known in advance. The propagation channel measurement unit 60 then detects propagation channel state information (CSI) from the difference between the characteristics superimposed on the actually received measurement signal and the initial characteristics. The CSI detected in this manner is provided to the notification signal generation unit 62.

The notification signal generator 62 provides the notification signal including the CSI generated by the propagation channel measurement unit 60 to one of the transmitters 58-1 to 58-3 that corresponds to the available frequency band. The transmitters 58-1 to 58-3 then transmit the notification signal including the CSI to the measurement request device 10 in the frequency band assigned to each of them.

[Processing flow in the first embodiment]
4 is a flowchart illustrating the flow of characteristic processing executed by the measurement requesting device 10. The routine shown in FIG. 4 is started each time a request to perform wireless sensing is issued. When this routine is started, it is first determined whether all of the frequency bands f1 to f3 are in a transmittable state (step 100).

If it is determined that all frequency bands are transmittable, a measurement request signal is transmitted in all frequency bands (step 102).

On the other hand, if it is determined in step 100 above that any of the frequency bands is in a non-transmittable state, it is determined whether the antenna unit assigned to the non-transmittable frequency band corresponds to any of the other transmittable frequency bands (step 104). For example, if frequency band f3 is non-transmittable, it is determined whether the antenna unit 16 corresponds to frequency bands f1 or f2.

If the determination in step 104 above is negative, it can be recognized that the antenna unit assigned to the non-transmittable frequency band cannot be used in other frequency bands. In this case, the measurement request signal is transmitted in a transmittable frequency band by the processing in step 102 above without using that antenna.

On the other hand, if the determination in step 104 above is positive, the antenna unit assigned to the unavailable frequency band is set as the additionally usable antenna unit, and the measurement request signal is transmitted using all antenna units (step 106). For example, if frequency band f3 is unavailable for transmission and antenna unit 16 supports frequency band f2, antenna unit 16 is set as the additionally usable antenna unit for f2. Then, a measurement request signal is transmitted from antenna unit 12 in frequency band f1, and measurement request signals are transmitted from antenna units 14 and 16 in frequency band f2.

After the above process is completed, it is then determined whether a measurement ready signal has been received from the measuring device 20 (step 108). This process is repeated until a measurement ready signal is received.

When reception of the measurement preparation completion signal is confirmed, measurement signals are transmitted in all frequency bands in which the signal was received (step 110). In other words, measurement signals are transmitted in all frequency bands in which transmission and reception is possible between the measurement request device 10 and the measurement device 20. At this time, if there are any unavailable frequency bands and an additional use antenna is set, that additional use antenna is used to transmit overlapping signals 36 in the available frequency bands, just as in the case of the measurement request signal.

Once the above processing is completed, it is then determined whether a notification signal has been received from the measuring device 20 (step 112).

If reception of a communication signal is not confirmed, it is determined whether a predetermined waiting time has elapsed (step 114). If it is determined that the predetermined time has not yet elapsed, the processing of step 112 is executed again. On the other hand, if it is determined that the predetermined time has elapsed, it is determined that the communication signal could not be received for some reason, and the processing from step 100 onwards is executed again.

If reception of a communication signal is confirmed in step 112 above, it is determined that the communication required for wireless sensing has been completed, and the routine shown in Figure 4 is terminated. Thereafter, the measurement request device 10 analyzes the notification signal for each frequency band, extracts the propagation channel state information (CSI) contained therein, and performs location detection or motion detection based on the extracted CSI.

Figure 5 is a flowchart illustrating the flow of characteristic processing executed by the measuring device 20 in this embodiment. The routine shown in Figure 5 is started when the measuring device 20 receives a measurement request signal from the measurement request device 10. When this routine is started, it is first determined whether the measurement request signal has been received in all frequency bands (step 120). As a result, if it is determined that the measurement request signal has been received in all frequency bands, the processing of step 124, described below, is then executed.

On the other hand, if it is determined in step 120 that the measurement request signal has not been received in any of the frequency bands, the following processing is performed to set up an additional antenna to be used and acquire the measurement request signal (step 122).
Step 122-1: An antenna unit assigned to a frequency band in which no measurement request signal is received is set as an additionally used antenna unit.
Step 122-2: The receiving units 50-1 to 50-3 also utilize the antenna unit set as the additionally used antenna unit to receive the measurement request signal.
Step 122-3: The receiving units 50-1 to 50-3 select the signal from the antenna unit with the strongest signal strength.

Once the above process is complete, it is determined whether the transmission mode of the measuring device 20 is set to synchronous mode (step 124). If it is determined that synchronous mode is set, the process of step 128, which will be described later, is executed.

On the other hand, if the setting of synchronous mode is not confirmed in step 124, the transmission mode of the measuring device 20 is changed to synchronous mode. Furthermore, a "change required" record is created to return the transmission mode to asynchronous mode after wireless sensing is completed (step 126).

Once the above processing is completed, a measurement preparation completion signal is transmitted in all frequency bands in which the measurement request signal was received (step 128). At this time, if some of the transmitting units 58-1 to 58-3 are unable to transmit, the antenna unit that covers the unable-to-transmit frequency band is set as the additional antenna unit to be used, and transmission is performed using all antennas.

After the above process is completed, it is next determined whether measurement signals from the measurement request device 10 have been received in all frequency bands (step 130). If reception in all frequency bands is confirmed, the process of step 134, described below, is then executed.

On the other hand, if it is determined that a measurement signal is not received in any frequency band, the following process is executed (step 132) in the same manner as in step 122 above.
Step 132-1: The antenna unit assigned to the frequency band not receiving the measurement signal is set as the additionally used antenna unit.
Step 132-2: The receiving units 50-1 to 50-3 also utilize the antenna unit set as the additionally used antenna unit to capture the measurement signal.
Step 132-3: The receiving units 50-1 to 50-3 select the signal from the antenna unit with the strongest signal strength.

After the above process is completed, the measurement device 20 measures the propagation channel state information (CSI) for each frequency band based on the received measurement signal. Furthermore, it transmits a notification signal including the measured CSI in all available frequency bands (step 134).

The above process completes the processing that the measuring device 20 must perform for wireless sensing. At this stage, the measuring device 20 determines whether "change required" is recorded in the control unit 52 (step 136).

If there are no records indicating "change required," the current routine is promptly terminated. On the other hand, if there are records indicating "change required," the transmission mode of the measuring device 20 is returned to asynchronous mode, and the records indicating "change required" are cleared.

According to the above processing, if some frequency bands are unavailable for transmission during wireless sensing, the measurement requesting device 10 and the measuring device 20 can use the hardware resources allocated to those frequency bands to transmit the overlapping signal 36 in available frequency bands. As a result, more information is exchanged between the measurement requesting device 10 and the measuring device 20 than when those hardware resources are stopped. Therefore, according to the wireless sensing system of this embodiment, even if some frequency bands are unavailable for transmission, it is possible to avoid a significant decrease in sensing accuracy compared to normal.

[Modification of the First Embodiment]
In the first embodiment described above, the measurement device 20 is caused to select a signal with a stronger signal strength when the overlapping signal 36 is transmitted. This process is not limited to being performed by the measurement device 20, and the same process may be performed by the measurement requesting device 10.

Furthermore, in the above-described first embodiment, when a duplicate signal 36 is transmitted, a signal with a strong signal strength is selected and used, but the present disclosure is not limited to this. When a duplicate signal 36 is transmitted in some frequency bands, CSI may be detected from both the normal signal and the duplicate signal 36, and both may be reflected in the results of wireless sensing.

Furthermore, in the above-described first embodiment, when some frequency bands are unavailable, the hardware resources utilized in the available frequency bands are limited to the antenna unit, but the present disclosure is not limited to this. In addition to the antenna unit, all hardware resources corresponding to other frequency bands can be made eligible for additional use in other frequency bands.

In addition, in the above-described first embodiment, both the measurement requesting device 10 and the measurement device 20 set the hardware resources (antenna units) allocated to the unavailable frequency band as additional use resources (additional use antenna units) for transmitting and receiving overlapping signals in other available frequency bands, but the present disclosure is not limited to this. The additional use resources may be set in only one of the measurement requesting device 10 and the measurement device 20.

10 Measurement request device 12, 14, 16, 22, 24, 26 Antenna section 20 Measurement device 30 Radio signal 32 f1 signal 34 f2 signal 36 Overlapping signal 40, 52 Control section 42 Measurement request signal generation section 44-1 to 44-3, 58-1 to 58-3 Transmitting section 46-1 to 46-3, 50-1 to 50-3 Receiving section 48 Measurement signal generation section 56 Measurement preparation completion signal generation section 60 Propagation channel measurement section 62 Notification signal generation section

Claims (8)

A wireless sensing system including a measurement requesting device having a plurality of wireless functions corresponding to different frequency bands in one housing, and a measuring device having a plurality of wireless functions corresponding to different frequency bands in one housing,
a process in which the measurement requesting device transmits measurement signals in a plurality of frequency bands;
a process in which the measurement device receives the measurement signals in a plurality of frequency bands and extracts propagation channel state information for each frequency band;
and calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information for each frequency band,
A wireless sensing system configured such that, when a frequency band that cannot be transmitted exists when the execution of wireless sensing is requested, at least one of the measurement requesting device and the measuring device executes a process of setting the wireless communication hardware resources allocated to the frequency band to additional usage resources to be used for transmitting overlapping signals in a frequency band that can be transmitted. At least one of the measurement requesting device and the measuring device
When execution of the wireless sensing is requested,
a determination process for determining whether signals from the other side are received in all of the different frequency bands;
a setting process for setting, when the signal from the other party is not received in a certain frequency band, the wireless communication hardware resource allocated to the certain frequency band as an additional use resource for receiving the overlapping signal in another frequency band;
The wireless sensing system of claim 1 configured to perform the following: the hardware resources include antenna units the number of which is equal to the number of the different frequency bands;
the additional use resource includes an additional use antenna unit for receiving the overlapping signal;
The wireless sensing system of claim 2, wherein the device that executes the discrimination process and the setting process, among the measurement request device and the measurement device, is configured to select the stronger signal from the overlapping signal received by the additionally used antenna unit and the signal in the same frequency band as the overlapping signal received by another antenna unit as the signal in that frequency band and use it as basic data for the wireless sensing. the hardware resources include antenna units the number of which is equal to the number of the different frequency bands;
the additional use resource includes an additional use antenna unit for receiving the overlapping signal;
The wireless sensing system of claim 2, wherein the device that executes the discrimination process and the setting process, among the measurement request device and the measurement device, is configured to extract the propagation channel state information from both the overlapping signal received by the additionally used antenna unit and a signal in the same frequency band as the overlapping signal received by another antenna unit, and use both of the extracted information as basic data for the wireless sensing. A wireless sensing system as described in claim 2, wherein at least one of the measurement request device and the measurement device is configured to set the hardware resource assigned to a non-transmittable frequency band as the additional usage resource to be used in one of the transmittable frequency bands when the hardware resource corresponds to one of the transmittable frequency bands. the hardware resources include antenna units the number of which is equal to the number of the different frequency bands;
the additional use resource includes an additional use antenna unit that transmits and receives the overlapping signal;
6. The wireless sensing system according to claim 2, wherein the measurement request device and the measurement device are configured to transmit and receive signals by utilizing all of the antenna units even when there is a frequency band in which transmission is prohibited. A wireless sensing method using a measurement requesting device having a plurality of wireless functions corresponding to different frequency bands in one housing, and a measuring device having a plurality of wireless functions corresponding to different frequency bands in one housing,
the measurement requesting device transmitting measurement signals in a plurality of frequency bands;
the measurement device receiving the measurement signals in a plurality of frequency bands and extracting propagation channel state information for each frequency band;
calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information for each frequency band;
When a frequency band that cannot be transmitted exists when the execution of the wireless sensing is requested, at least one of the measurement requesting device and the measuring device sets a wireless communication hardware resource that has been allocated to the frequency band as an additional use resource to be used for transmitting overlapping signals in a frequency band that can be transmitted;
A wireless sensing method comprising: A measurement requesting device that realizes a wireless sensing function based on the results of information communication with a measuring device having multiple wireless functions corresponding to different frequency bands in a single housing,
It has multiple wireless functions corresponding to different frequency bands in one housing,
transmitting measurement signals in multiple frequency bands to the measurement device;
receiving a notification signal transmitted by the measurement device for each frequency band, the notification signal including propagation channel state information extracted from the measurement signal for each frequency band;
calculating a result of wireless sensing of a space between the measurement requesting device and the measuring device based on the propagation channel state information extracted from the notification signal for each frequency band;
a process of setting, when a frequency band that cannot be transmitted exists when the execution of the wireless sensing is requested, the wireless communication hardware resource that has been allocated to the frequency band in question as an additional use resource to be used for transmitting overlapping signals in a frequency band that can be transmitted;
a measurement requesting device configured to perform the steps of: