Communication apparatus, wireless device, and program

Abstract

To reduce the amount of data on the reception result of a sensing signal fed back by a wireless device.SOLUTION: A communication apparatus includes transmitting means for transmitting sensing signals via a plurality of respective transmission beams, and notifying means for notifying a feedback condition to a wireless device that receives the sensing signals transmitted by the transmitting means via one or more reception beams. The feedback condition indicates one or more conditions that must be satisfied by a target sensing signal whose reception result the wireless device feeds back to the communication apparatus, among the sensing signals received by the wireless device via the one or more respective reception beams.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present disclosure relates to sensing technology using sensing signals.

Background Art

[0002] Non-Patent Document 1 discloses various use cases of sensing services in a mobile communication network. In one of the configurations disclosed in Non-Patent Document 1, a base station device (BS), which is a wireless communication device, transmits a sensing signal, and a wireless device (WD) feeds back the reception result of the sensing signal to the base station device. Thus, the base station device collects sensing data. Based on the collected sensing data, the base station device detects the environment of the area where the base station device provides services, for example, obstacles that hinder the propagation of wireless signals. Note that the obstacles include stationary objects such as buildings and moving objects such as vehicles. Note that it is also conceivable to efficiently perform communication and sensing by utilizing signals used for communication as sensing signals.

[0003] Patent Document 1 discloses a system called ISAC (Integrated Sensing And Communication) that integrates sensing signals and communication signals.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Non-Patent Documents

[0005]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] For example, as shown in FIG. 1, BS1 is configured to transmit N (N is an integer greater than or equal to 2) transmission beams T#1 to T#N, and each WD2 is configured to receive M (M is an integer greater than or equal to 1) reception beams R#1 to R#M. Then, a sensing signal (hereinafter referred to as a sensing signal) is transmitted to BS1 by each of the N transmission beams. By configuring it in this way, each WD2 can receive the sensing signals transmitted by the N transmission beams in each of the M reception beams.

[0007] That is, if the reception result of the sensing signal transmitted by the transmission beam T#n (n is an integer from 1 to N) in the reception beam R#m (m is an integer from 1 to M) is denoted as reception result #nm, each WD2 can obtain up to N×M reception results of reception result #11 to reception result #NM. Therefore, each WD2 feeds back feedback data indicating up to N×M reception results to BS1, and BS1 can perform sensing based on the feedback data indicating up to N×M reception results from each WD2.

[0008] However, when the data amount of the feedback data from each WD2 increases, the calculation amount of BS1 increases, that is, the processing load of BS1 increases.

[0009] The present disclosure provides a technique for reducing the data amount of the reception results of the sensing signals fed back by wireless devices.

Means for Solving the Problem

[0010] According to one aspect of the present disclosure, a communication device includes: transmission means for transmitting sensing signals with respect to a plurality of transmission beams respectively; and notification means for notifying a wireless device that receives the sensing signals transmitted by the transmission means with one or more reception beams of feedback conditions, wherein the feedback conditions indicate one or more conditions that a target sensing signal, among the sensing signals received by the wireless device with each of the one or more reception beams, which the wireless device feeds back a reception result to the communication device, should satisfy.

Advantages of the Invention

[0011] According to the present disclosure, it is possible to reduce the amount of data of the reception result of the sensing signal fed back by the wireless device.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

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Figure 7

Figure 8

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the invention according to the claims, and not all combinations of the features described in the embodiments are essential to the invention. Two or more of the plurality of features described in the embodiments may be arbitrarily combined. Also, the same or similar configurations are given the same reference numerals, and redundant descriptions are omitted.

[0014] FIG. 1 is a system configuration diagram according to this embodiment. According to FIG. 1, the system includes one BS1 and two WDs2 existing within the service area of the BS1. Note that the number of WDs2 existing within the service area of one BS1 can be any number of 1 or more. BS1 is configured to transmit N (N is an integer of 2 or more) transmission beams T#1 to T#N. Also, each WD2 is configured to receive M (M is an integer of 1 or more) reception beams R#1 to R#M.

[0015] Furthermore, BS1 is configured to transmit a sensing signal with each of the N transmission beams. As the sensing signal, for example, a downlink reference signal (RS) defined by 3GPP (registered trademark) can be used. As an example, channel state information (CSI)-RS can be used as the sensing signal.

[0016] Each WD2 can receive the sensing signals transmitted with the N transmission beams in each of the M reception beams. In the following description, the sensing signal transmitted with the transmission beam T#n (n is an integer from 1 to N) and received with the reception beam R#m (m is an integer from 1 to M) is denoted as sensing signal #nm, and the reception result of the sensing signal #nm is denoted as reception result #nm. Note that each WD2 can distinguish the sensing signals #1m to #Nm received with the reception beam R#m, for example, by its reception timing, frequency, pattern, or the like.

[0017] FIG. 2 is a sequence diagram according to the present embodiment. Note that FIG. 2 shows the sequence between BS1 and one WD2. The sequence in FIG. 2 is performed between BS1 and each WD2 within the service area of the BS1. In S1, BS1 determines the feedback conditions (feedback criteria) to be applied to each WD2. In S2, BS1 notifies WD2 of the conditions determined in S1. In S3, BS1 transmits sensing signals using transmission beams T#1 to T#N respectively. In S4, WD2 receives the sensing signals transmitted by BS1 using transmission beams T#1 to T#N respectively using reception beams R#1 to R#M respectively. As described above, WD2 receives up to N×M sensing signals #11 to #NM and obtains up to N×M reception results #11 to #NM.

[0018] In S5, WD2 determines the feedback target sensing signals that satisfy the feedback conditions notified from BS1 in S2. Then, in S6, WD2 feeds back only the reception results of the feedback target sensing signals to BS1. Note that the feedback conditions notified to each WD2 in S2 can be different for each WD2. That is, BS1 does not need to notify the same feedback conditions to all WD2s existing within its service area. The feedback conditions may include one or more conditions that the feedback target sensing signals should satisfy. Hereinafter, examples of the conditions that can be included in the feedback conditions will be described. Note that FIGS. 3 to 6 below show a total of 64 sensing signals #11 to #88 in the case where N = 8 and M = 8.

[0019] <Condition #1> The feedback target sensing signal is a sensing signal whose received power at WD2 is greater than the first threshold, and this condition is Condition #1. When including Condition #1 in the feedback condition, BS1 can notify WD2 of the first threshold at S2. Alternatively, the first threshold can be notified to WD2 beforehand, and at S2, only the application of Condition #1 can be notified. For example, among the 64 sensing signals shown in Figure 3, the 19 shaded sensing signals indicate sensing signals whose received power was greater than the first threshold. When only Condition #1 is applied, WD2 transmits feedback data indicating the received results of the 19 shaded signals to BS1 at S6. The received results of sensing signals with low received power do not contribute much to the sensing accuracy at BS1. Therefore, by not feeding back the received results of sensing signals with low received power to BS1, the amount of data fed back to BS1 can be reduced without affecting the sensing accuracy.

[0020] <Condition #2> The feedback target sensing signal is a sensing signal transmitted by one or more specified transmission beams among N transmission beams, and this condition is Condition #2. When including Condition #2 in the feedback condition, BS1 notifies WD2 of information indicating one or more specified transmission beams at S2. For example, Figure 4 shows a case where transmission beams T#1 and T#2 are specified transmission beams. When only Condition #2 is applied, WD2 transmits feedback data indicating the received results of the 16 shaded sensing signals to BS1 at S6. For example, based on the direction of WD2 relative to BS1, BS1 can determine a transmission beam expected to have high received quality at WD2 and a transmission beam expected to have low received quality at WD2. By setting the transmission beam expected to have high received quality at WD2 as the specified transmission beam, the amount of data fed back to BS1 can be reduced without affecting the sensing accuracy.

[0021] <Condition #3> The feedback target sensing signal is applicable when WD2 can configure multiple reception beams, and the condition #3 is that it is a sensing signal received by one or more specified reception beams among the multiple reception beams. When including condition #3 in the feedback condition, at S2, BS1 notifies WD2 of information indicating one or more specified reception beams. For example, FIG. 5 shows a case where reception beams R#2 to R#4 are the specified reception beams. When only condition #3 is applied, at S6, WD2 transmits feedback data indicating the reception results of the 24 masked sensing signals to BS1. For example, when it is desired to accurately detect an obstacle at a specific position, by designating the reception beam facing the direction of the obstacle as the specified reception beam, the amount of data to be fed back to BS1 can be reduced without affecting the sensing accuracy at BS1.

[0022] <Condition #4> The condition #4 is that the feedback target sensing signal is a sensing signal whose absolute value of the Doppler shift is greater than (or equal to) a second threshold value, or less than (or equal to) the second threshold value. When including condition #4 in the feedback condition, at S2, BS1 notifies WD2 whether to target for feedback the second threshold value and the sensing signals whose absolute value of the Doppler shift is greater than the second threshold value, or whether to target for feedback the sensing signals whose absolute value of the Doppler shift is less than the second threshold value. Alternatively, the second threshold value can be notified to WD2 beforehand, and at S2, WD2 can be notified whether to target for feedback the sensing signals whose absolute value of the Doppler shift is greater than the second threshold value, or whether to target for feedback the sensing signals whose absolute value of the Doppler shift is less than the second threshold value. Furthermore, it can also be configured to notify WD2 beforehand whether to target for feedback the sensing signals whose absolute value of the Doppler shift is greater than the second threshold value, or whether to target for feedback the sensing signals whose absolute value of the Doppler shift is less than the second threshold value. In this case, at S2, BS1 notifies WD2 to apply condition #4.

[0023] When an obstacle is moving, the absolute value of the Doppler shift of the sensing signal reflected by the obstacle increases as the moving speed of the obstacle increases. Therefore, when it is desired to detect an obstacle moving faster than a predetermined moving speed, by using a sensing signal whose absolute value of the Doppler shift is greater than a second threshold value as a feedback target sensing signal, it is possible to reduce the amount of data to be fed back to BS1 without affecting the sensing accuracy. Similarly, when it is desired to detect an obstacle moving slower than a predetermined moving speed or a stationary obstacle, by using a sensing signal whose absolute value of the Doppler shift is less than the second threshold value as a feedback target sensing signal, it is possible to reduce the amount of data to be fed back to BS1 without affecting the sensing accuracy.

[0024] Note that when the obstacle is moving toward WD2, the Doppler shift is a positive value, and when the obstacle is moving away from WD2, the Doppler shift is a negative value. Therefore, when it is desired to detect an obstacle moving toward WD2 or an obstacle moving away from WD2, it is also possible to adopt a configuration in which the Doppler shift is compared with the second threshold value instead of the absolute value of the Doppler shift. The four shaded areas in FIG. 6 indicate, for example, sensing signals whose absolute value of the Doppler shift is greater than the second threshold value. When only condition #4 is applied, WD2 transmits feedback data indicating four reception results to BS1 in S6.

[0025] Note that the feedback condition may include one or more of the above four conditions. For example, by combining Condition #1 and Condition #2, only the reception results of the sensing signals with a reception power at WD2 greater than the first threshold among the sensing signals transmitted with the specified transmission beam can be fed back to WD2. Also, by combining Condition #2 and Condition #3, only the reception results of the sensing signals transmitted with the specified transmission beam and received with the specified reception beam can be fed back to WD2. Furthermore, by combining Condition #1, Condition #3, and Condition #4, only the reception results of the sensing signals received with the specified reception beam, with a reception power greater than the first threshold and an absolute value of Doppler shift greater than the second threshold, can be fed back to WD2. The same applies to other combinations. Also, the feedback condition may include, in addition to, or instead of, one or more of the above four conditions, other conditions. That is, the feedback condition may be set so as to feed back to WD2 the reception results contributing to the sensing accuracy based on the content of the sensing process and not to feed back the reception results not contributing to the sensing accuracy to WD2.

[0026] Furthermore, the feedback condition may include a condition regarding the number of sensing signals to be the feedback target. For example, regarding Condition #1, a condition can be provided that, among the sensing signals with a reception power greater than the first threshold, the maximum S sensing signals in descending order of reception power are set as the sensing signals to be the feedback target. In this case, even if there are S or more sensing signals with a reception power greater than the first threshold, only the reception results of the top S sensing signals in reception power are fed back to BS1. On the other hand, when the number of sensing signals with a reception power greater than the first threshold is less than S, the reception results of all the sensing signals with a reception power greater than the first threshold are fed back to BS1. When specifying the upper limit value of the number of sensing signals to be the feedback target in the feedback condition, information on how to narrow down the sensing signals satisfying other conditions to the upper limit value when the number of sensing signals satisfying other conditions is more than the upper limit value can also be specified in the feedback condition.

[0027] <Configuration of BS1> FIG. 7 shows a configuration example of BS1. Note that in FIG. 7, only the parts necessary for the description of the embodiment are shown, and the parts of BS1 that are not necessary for the description of the embodiment are omitted. The transmission unit 11 transmits a downlink radio signal. The reception unit 12 receives an uplink radio signal. Note that the antenna used by the transmission unit 11 to transmit a radio signal may be used only by the transmission unit 11 or may be shared with the reception unit 12. The transmission unit 11 may be configured to transmit a radio signal with a plurality of transmission beams. Further, the transmission unit 11 may be configured to transmit a sensing signal with each of the plurality of transmission beams. The sensing signal is, for example, CSI-RS. When the reception unit 12 receives feedback data indicating the reception result of the feedback target sensing signal from WD2, the reception unit 12 outputs the feedback data to the sensing processing unit 10. For example, the feedback data may be transmitted by a CSI feedback signal.

[0028] The sensing processing unit 10 performs processing related to sensing. For example, the sensing processing unit 10 also functions as a notification unit that notifies WD2 of feedback conditions including one or more conditions via the transmission unit 11. The feedback conditions indicate the conditions of the feedback target sensing signal. The conditions may include, for example, one or more of the above-described condition #1 to condition #4. Further, the conditions may include an upper limit value of the number of feedback target sensing signals.

[0029] <Configuration of WD2> FIG. 8 shows a configuration example of WD2. Note that in FIG. 8, only the parts necessary for the description of the embodiment are shown, and the parts of WD2 that are not necessary for the description of the embodiment are omitted. The transmission unit 21 transmits an uplink radio signal. The reception unit 22 receives a downlink radio signal. Note that the antenna used by the reception unit 22 to receive a radio signal may be used only by the reception unit 22 or may be shared with the transmission unit 21. The reception unit 22 may be configured to receive a radio signal with one or more reception beams.

[0030] The feedback processing unit 20 performs processing related to the feedback of the sensing signal received from BS1. For example, the feedback processing unit 20 receives feedback conditions from BS1 via the receiving unit 22. The feedback conditions indicate one or more conditions that the sensing signal to be the feedback target sensing signal among the sensing signals received by the receiving unit 22 should satisfy. The feedback processing unit 20 feeds back the reception result of the feedback target sensing signal determined based on the feedback conditions to BS1 via the transmitting unit 21.

[0031] Note that BS1 may be implemented by one device, or may be composed of a plurality of devices arranged in different locations, such as a radio unit (RU), a distributed unit (DU), and a central unit (CU), or a baseband unit (BBU) and a remote radio unit (RRU). Further, although BS (base station device) 1 has been described as transmitting a sensing signal, the device that transmits the sensing signal is not limited to the base station device in the mobile communication network, and can be any wireless communication device having the functions shown in FIG. 7, such as a wireless LAN access point device. Also, WD2 is not limited to the wireless device in the mobile communication network, and can be any wireless device having the functions shown in FIG. 8.

[0032] Furthermore, according to the present disclosure, a program executable by one or more processors is provided. When the program is executed by one or more processors of the device, the program includes instructions for causing the device to function as a wireless communication device such as BS1 or a wireless device such as WD2. Further, according to the present disclosure, a non-transitory computer-readable storage medium storing the above program is provided. Further, according to the present disclosure, a method executed by a wireless communication device such as BS1 or a method executed by a wireless device such as WD2 according to the sequence shown in FIG. 2 is provided. Further, according to the present disclosure, a program for causing a device having one or more processors to execute these methods and a non-transitory computer-readable storage medium storing the program are provided.

[0033] The invention is not limited to the above embodiments, and various modifications and changes are possible within the scope of the gist of the invention.

[0034] With the above configuration, the amount of data of the reception result of the sensing signal fed back by the wireless device can be reduced. Therefore, it becomes possible to contribute to Goal 9 of the Sustainable Development Goals (SDGs) led by the United Nations, which is to "build resilient infrastructure, promote sustainable industrialization, and foster innovation."

Description of Reference Numerals

[0035] 10: Sensing processing unit, 11: Transmitting unit, 12: Receiving unit

Claims

1. A communication device, a transmission means for transmitting a sensing signal with each of a plurality of transmission beams, a notification means for notifying a feedback condition to a wireless device that receives the sensing signal transmitted by the transmission means with one or more reception beams, comprising: wherein the feedback condition indicates one or more conditions that a target sensing signal, for which the wireless device feeds back a reception result to the communication device, among the sensing signals received by the wireless device with each of the one or more reception beams, must satisfy. A communication device.

2. The communication device according to claim 1, wherein the one or more conditions include a condition with a sensing signal whose received power at the wireless device is greater than a first threshold value.

3. The communication device according to claim 1, wherein the one or more conditions include a condition with a sensing signal transmitted with one or more designated transmission beams among the plurality of transmission beams.

4. The one or more reception beams are a plurality of reception beams, The communication device according to claim 1, wherein the one or more conditions include a condition with a sensing signal received with one or more designated reception beams among the plurality of reception beams.

5. The communication device according to claim 1, wherein the one or more conditions include a condition with a sensing signal whose Doppler shift is greater than a second threshold value, or whose absolute value of the Doppler shift is greater than the second threshold value.

6. The communication device according to claim 1, wherein the one or more conditions include a condition with a sensing signal whose Doppler shift is less than a second threshold value, or whose absolute value of the Doppler shift is less than the second threshold value.

7. The communication device is a base station device, The communication device according to claim 1, wherein the sensing signal is a channel state information reference signal (CSI-RS).

8. A wireless device that receives sensing signals transmitted from a communication device with each of a plurality of transmission beams with one or more reception beams, a reception means for receiving a feedback condition from the communication device, a feedback means for feeding back to the communication device a reception result of a feedback target sensing signal that satisfies one or more conditions indicated by the feedback condition among the sensing signals transmitted by the communication device and received with each of the one or more reception beams. A wireless device comprising.

9. The wireless device according to claim 8, wherein the one or more conditions include a condition with a sensing signal whose received power at the wireless device is greater than a first threshold value.

10. The wireless device according to claim 8, wherein the one or more conditions include a condition with a sensing signal transmitted by one or more designated transmission beams among the plurality of transmission beams.

11. The one or more reception beams are a plurality of reception beams, The wireless device according to claim 8, wherein the one or more conditions include a condition with a sensing signal received by one or more designated reception beams among the plurality of reception beams.

12. The wireless device according to claim 8, wherein the one or more conditions include a condition with a sensing signal whose Doppler shift is greater than a second threshold value, or whose absolute value of the Doppler shift is greater than the second threshold value.

13. The wireless device according to claim 8, wherein the one or more conditions include a condition with a sensing signal whose Doppler shift is less than a second threshold value, or whose absolute value of the Doppler shift is less than the second threshold value.

14. A program that, when executed by one or more processors of a device, causes the device to function as the communication device according to any one of claims 1 to 7.

15. A program that, when executed by one or more processors of a device, causes the device to function as the wireless device according to any one of claims 8 to 13.

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