Wireless communication system, control device, wireless communication method and program

Abstract

To improve the quality of wireless communication based on both line-of-sight environment and non-line-of-sight environment around a wireless communication device.SOLUTION: A first wireless communication device includes a wireless communication unit that forms a beam and communicates wirelessly with a second wireless communication device, a beam control unit that controls the beam, and an acquisition unit that acquires sound information in which sound around its own device is collected. The second wireless communication device receives a reference signal transmitted by the wireless communication unit using each of multiple types of beams under the control of the beam control unit, and notifies transmission information indicating information about the wireless transmission of the received reference signal. The first wireless communication device or control device includes an estimation and prediction unit that uses the transmission information and the sound information to estimate or predict the propagation environment and future communication quality between the first wireless communication device and the second wireless communication device, and the probability of the second wireless communication device being in an area, and a control unit that controls wireless communication between the first wireless communication device and the second wireless communication device based on results of the estimation or prediction.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a wireless communication system, a control device, a wireless communication method, and a program. [Background Art]

[0002] In systems such as 5G (the 5th generation mobile communication system), high frequency bands in the millimeter wave band are used. In addition, in order to achieve further higher speed and larger capacity in future wireless communication systems such as 6G (the 6th generation mobile communication system), the use of further higher frequency bands that can secure wider bandwidth is envisioned (see, for example, Non-Patent Document 1). However, high frequency bands have large propagation loss, high straightness and low transmittance. Therefore, high frequency bands are significantly affected by degradation of communication quality due to blocking (see, for example, Non-Patent Document 2).

[0003] To avoid degradation of communication quality, it is common to use a means for detecting fluctuations in communication quality and performing radio station switching control. In addition, it has been proposed to perform radio station switching control before communication quality degradation based on prediction using a camera (see, for example, Non-Patent Document 3). According to this technology, it has been shown that there is a possibility of avoiding a decrease in communication quality caused by blocking of a line-of-sight communication path. Furthermore, communication radio sensing using beam sweep without using an external sensing device has also been proposed (see, for example, Non-Patent Document 4), and it has been shown that there is a possibility of efficiently improving communication quality while suppressing increases in the size and cost of a wireless communication device. [Prior Art Documents] [Non-Patent Documents]

[0004] [Non-Patent Document 1] "White Paper 5G Evolution and 6G", NTT DOCOMO, INC., Version 4.0, January 2022 [Non-Patent Document 2] 3GPP TR38.901 V16.0.0: "Study on channel model for frequencies from 0.5 to 100 GHz (Release 16)," Oct. 2019. [Non-Patent Document 3] Y. Koda, K. Nakashima, K. Yamamoto, T. Nishio, and M. Morikura, "Handover Management for mmWave Networks With Proactive Performance Prediction Using Camera Images and Deep Reinforcement Learning," IEEE Transactions on Cognitive Communications and Networking, vol. 6, no. 2, June 2020. [Non-Patent Document 4] "Shielding Prediction Using Beam Pair Scanning in Millimeter-Wave Communication," IEICE Communications Society Conference 2022, B-15-3, 2022. [Overview of the project] [Problems that the invention aims to solve]

[0005] When detecting fluctuations in communication quality and performing wireless station switching control, it is unavoidable that there will be a temporary deterioration in communication quality from the time of fluctuation detection until the control is completed. Furthermore, it is difficult to grasp situations beyond the line of sight using information such as received power that can be obtained during beam sweeping, or sensing by cameras. Therefore, it is difficult to realize control of wireless communication equipment based on situations beyond the line of sight.

[0006] In view of the above circumstances, the present invention aims to provide a wireless communication system, control device, wireless communication method, and program that can improve the quality of wireless communication based on both the line-of-sight environment and the non-line-of-sight environment surrounding the wireless communication device. [Means for solving the problem]

[0007] One aspect of the present invention is a wireless communication system comprising one or more first wireless communication devices and one or more second wireless communication devices, wherein the first wireless communication device comprises a wireless communication unit that forms a beam and communicates wirelessly with the second wireless communication device, a beam control unit that controls the beam formed by the wireless communication unit, and an acquisition unit that acquires sound information picked up around itself; the second wireless communication device receives a reference signal transmitted by the wireless communication unit by each of a plurality of types of beams under the control of the beam control unit, and includes a notification unit that notifies transmission information indicating information regarding the wireless transmission of the received reference signal; the first wireless communication device or a control device connected to the first wireless communication device comprises an estimation and prediction unit that estimates or predicts the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device, using the transmission information notified by the notification unit and the sound information acquired by the acquisition unit; and a control unit that controls wireless communication between the first wireless communication device and the second wireless communication device based on the estimation or prediction results by the estimation and prediction unit.

[0008] One aspect of the present invention relates to a wireless communication system comprising one or more first wireless communication devices, one or more second wireless communication devices, and a control device for controlling the first wireless communication device, the control device comprising: an estimation and prediction unit that acquires transmission information indicating information relating to wireless transmission when the second wireless communication device receives a reference signal transmitted from the first wireless communication device by each of a plurality of types of beams, and sound information picked up around the first wireless communication device, and estimates or predicts the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device using the acquired transmission information and sound information; and a control unit that controls wireless communication between the first wireless communication device and the second wireless communication device based on the results of the estimation or prediction by the estimation and prediction unit.

[0009] One aspect of the present invention is a wireless communication method in a wireless communication system having one or more first wireless communication devices and one or more second wireless communication devices, the wireless communication method comprising: a transmission step in which the first wireless communication device transmits a wireless reference signal using each of a plurality of types of beams; an acquisition step in which the first wireless communication device acquires sound information picked up around itself; a notification step in which the second wireless communication device receives a reference signal transmitted from the first wireless communication device using each of a plurality of types of beams and notifies transmission information indicating information regarding the wireless transmission of the received reference signal; an estimation and prediction step in which the first wireless communication device or a control device connected to the first wireless communication device estimates or predicts the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device, using the transmission information notified in the notification step and the sound information acquired in the acquisition step; and a control step in which the first wireless communication device or the control device controls wireless communication between the first wireless communication device and the second wireless communication device based on the results of the estimation or prediction in the estimation and prediction step.

[0010] One aspect of the present invention is a program for causing a computer to function as the control device described above. [Effects of the Invention]

[0011] The present invention makes it possible to improve the quality of wireless communication based on both the line-of-sight environment and the non-line-of-sight environment surrounding the wireless communication device. [Brief explanation of the drawing]

[0012] [Figure 1] This is a diagram showing the configuration of a wireless communication system according to one embodiment of the present invention. [Figure 2] This is a functional block diagram of a wireless communication device and control device according to the same embodiment. [Figure 3] This is a flowchart illustrating the wireless control of the wireless communication device and control device according to the same embodiment. [Figure 4] This is a sequence diagram showing an example of the operation of a wireless communication system according to the same embodiment. [Figure 5] This figure shows the hardware configuration of the control device according to the same embodiment. [Modes for carrying out the invention]

[0013] Embodiments of the present invention will be described in detail below with reference to the drawings. In this embodiment, the wireless communication device uses a combination of transmission information such as received power, communication quality, communication distance, reception timing, and channel state information (CSI) for each beam obtained by beam sweeping, and ambient sound information acquired by the wireless communication device, to estimate or predict at least a part of the future presence or absence of an area within the communication range of a peer wireless communication device communicating with the wireless communication device, as well as communication quality, propagation shielding, and reflection environment. The estimation or prediction results are then used for control to improve communication quality.

[0014] In high-frequency wireless communication systems such as millimeter waves, radio waves have strong directional properties, making them susceptible to shielding. Therefore, sensing to understand the environment and perform control is conceivable. However, sensing using high-frequency communication radio waves, cameras, and LiDAR (light detection and ranging) makes it difficult to understand conditions beyond the line of sight, making it difficult to realize control based on conditions beyond the line of sight. The wireless communication system of this embodiment combines sensing based on high-frequency communication radio waves, which have high sensing performance in line-of-sight environments, with sensing based on sound information, which can understand conditions beyond the line of sight, to complementarily improve sensing performance and predict and estimate the presence of shielding / reflection environments and opposing wireless communication devices. Based on these prediction and estimation results, the wireless communication system of this embodiment performs control such as sleep control and switching control (handover control) of the wireless communication device. As a result, the wireless communication system of this embodiment can perform control based on understanding conditions in both line-of-sight and non-line-of-sight environments, and is expected to reduce power consumption through sleep control of the wireless communication device and improve communication quality through efficient handover control.

[0015] Figure 1 shows an example configuration of a wireless communication system 1 according to one embodiment of the present invention. The wireless communication system 1 comprises a opposing wireless communication device 2, a wireless communication device 3, and a control device 4. Figure 1 shows one opposing wireless communication device 2 and two wireless communication devices 3, but the number of opposing wireless communication devices 2 and wireless communication devices 3 is arbitrary. The opposing wireless communication device 2 and the wireless communication devices 3 communicate wirelessly. Wireless communication between the opposing wireless communication device 2 and the wireless communication devices 3 is affected by shielding and reflection by fixed shielding objects 5 and variable shielding objects 6. The wireless communication device 3 is also connected to the control device 4.

[0016] The wireless communication device 3 has a function to perform beamforming by controlling one or both of the phase and amplitude of multiple antenna elements. Furthermore, the wireless communication device 3 has a function to perform beam sweeping, which sweeps while changing the beam formed by beamforming. The wireless communication device 3 has a function to receive transmission information from the opposing wireless communication device 2 when wireless transmission is performed with each type of beam during beam sweeping. The transmission information includes one or more of the following for each beam: received signal strength, signal-to-noise power ratio, communication distance, propagation path information, etc. Furthermore, the transmission information includes one or both of the reception timing of the beam from which the received signal strength, signal-to-noise power ratio, communication distance, or propagation path information was obtained, and information that identifies the beam, such as the beam index. Received signal strength and signal-to-noise power ratio are examples of information on communication quality. The reception timing may be expressed as the reception time at the opposing wireless communication device 2. If the transmission order and time of each beam in beam sweeping are predetermined, the reception timing may be expressed as the reception order. The reception timing can also be used as information that identifies the beam formed by the wireless communication device 3. In addition to having the function of communicating with the opposing wireless communication device 2, the wireless communication device 3 has a mechanism for collecting sound information such as a microphone. The wireless communication device 3 may have one microphone or multiple microphones, and may be configured as a microphone array.

[0017] The control device 4 receives, from the wireless communication device 3, transmission information of each type of beam fed back from the opposing wireless communication device 2 and sound information collected using a microphone or the like. The control device 4 has a function of estimating or predicting, using the acquired transmission information and sound information, the propagation environment between the opposing wireless communication device 2 and the wireless communication device 3 such as shielding or reflection caused by a fixed shielding object 5 or a variable shielding object 6, the future communication quality of wireless communication between the opposing wireless communication device 2 and the wireless communication device 3, and the in-area residence probability which is the probability that the opposing wireless communication device 2 will reside in the communication area of the wireless communication device 3 in the future. The in-area residence probability includes the presence or absence of in-area residence indicating whether the opposing wireless communication device 2 will reside in the communication area of the wireless communication device 3 in the future. The control device 4 may use an estimation model for this estimation or prediction. The estimation model represents the correspondence between one or more pieces of information included in the transmission information and the sound information, and the propagation environment to be estimated or predicted, future communication quality, and future in-area residence probability. Machine learning may be used for the estimation model, or a prediction method such as linear prediction may be used. Hereinafter, information representing the propagation environment, future communication quality, and in-area residence probability estimated or predicted by the estimation model is referred to as estimation result information. Note that the control device 4 may use, for estimation or prediction, in addition to transmission information between the opposing wireless communication device 2 and the wireless communication device 3 that is the communication counterpart of the opposing wireless communication device 2, transmission information between the opposing wireless communication device 2 and a wireless communication device 3 that is not the communication counterpart of the opposing wireless communication device 2. Furthermore, the control device 4 may use, for estimation or prediction, in addition to sound information collected by the wireless communication device 3 that is the communication counterpart of the opposing wireless communication device 2, sound information collected by a wireless communication device 3 that is not the communication counterpart of the opposing wireless communication device 2. Furthermore, the control device 4 may perform estimation or prediction by weighting the transmission information fed back from the opposing wireless communication device 2 and the sound information collected by the wireless communication device 3 based on position information, past history, or the like of the opposing wireless communication device 2.

[0018] The control device 4 has a function of controlling wireless communication between the opposing wireless communication device 2 and the wireless communication device 3 based on estimation result information obtained by using transmission information and sound information of each type of beam. For example, the control device 4 selects a beam to be used for data communication between the opposing wireless communication device 2 and the wireless communication device 3 based on the estimation result information, and controls the wireless communication device 3 to form the selected beam. Further, for example, the control device 4 controls to switch the wireless communication device 3 to which the opposing wireless communication device 2 is connected, based on the estimation result information. The control device 4 may use the estimation result information for beam directivity control in beamforming of the wireless communication device 3, or may use the estimation result information for reducing a beam search range, sleep control of the wireless communication device 3, or the like.

[0019] Note that the wireless communication device 3 may include one or both of an estimation or prediction function using an estimation model, and a function of controlling wireless communication between the opposing wireless communication device 2 and the wireless communication device 3 based on the estimation result information. Further, the control device 4 may be a device integrated with the wireless communication device 3. Further, the control device 4 may cooperatively control a plurality of wireless communication devices 3.

[0020] Based on the transmission information and the sound information, in addition to estimating or predicting the position of the fixed shielding object 5 in the line-of-sight between the opposing wireless communication device 2 and the wireless communication device 3, grasping the presence and predicting the movement of the variable shielding object 6 existing outside the line-of-sight makes it possible to expect improvement in estimation and prediction accuracy by expanding the environment grasping range including inside and outside the line-of-sight.

[0021] Figure 2 is a block diagram showing an example of a functional configuration of the wireless communication device 3 and the control device 4 according to the present embodiment. The wireless communication device 3 includes a transmission unit 31, a signal processing unit 32, a beam control unit 33, a transmission / reception unit 34, a plurality of antenna elements 35, a microphone 36, and a collection unit 37.

[0022] The transmission unit 31 is a functional unit that transmits signals to the control device 4 and other higher-level devices (not shown) on the network. The signal processing unit 32 is a functional unit that performs signal processing in wireless communication. For example, the signal processing unit 32 receives transmission data from a higher-level device or control device 4 on the network destined for the opposing wireless communication device 2 via the transmission unit 31. The signal processing unit 32 converts the transmission data destined for the opposing wireless communication device 2 into signals to be transmitted from each antenna element 35 and outputs it to the beam control unit 33. The signal processing unit 32 also receives a received signal, which is a composite of the signals received by each antenna element 35, from the beam control unit 33 and obtains the signal transmitted from the opposing wireless communication device 2 from the received signal. The signal processing unit 32 outputs the obtained signal from the opposing wireless communication device 2 to a higher-level device or control device 4 on the network via the transmission unit 31.

[0023] The beam control unit 33 is a functional unit that controls the formation of the beam. The transmitting / receiving unit 34 is a functional unit that performs beamforming by controlling either or both of the phase and amplitude of the signal, and performs processing related to the transmission and reception of signals. For example, the beam control unit 33 adjusts the weight of each antenna element 35 so that the directivity of the radio waves is formed in a predetermined beam direction. When transmitting a wireless signal, the beam control unit 33 outputs the transmission signals from each antenna element 35 generated by the signal processing unit 32 to the transmitting / receiving unit 34, and also instructs the weight of each antenna element 35 to form a beam. The transmitting / receiving unit 34 uses the weight instructed by the beam control unit 33 to adjust either or both of the phase and amplitude of the signal transmitted from each antenna element 35 to form a beam and transmit the wireless signal. Also, when receiving a wireless signal, the beam control unit 33 instructs the transmitting / receiving unit 34 to adjust the weight of each antenna element 35 to form a beam. The transmitting / receiving unit 34 uses the weight instructed by the beam control unit 33 to adjust either or both of the phase and amplitude of the wireless signal received by each antenna element 35. The transmitting / receiving unit 34 outputs a received signal obtained by synthesizing each adjusted wireless signal to the beam control unit 33. The beam control unit 33 outputs the received signal input from the transmitting / receiving unit 34 to the signal processing unit 32.

[0024] The collection unit 37 collects sound information from the vicinity of the wireless communication device 3 through the microphone 36. The sound information to be collected may be ambient sounds from the vicinity of the wireless communication device 3, or sounds extracted from the sound collected by the microphone 36, limited to a specific frequency range, and may be either audible or inaudible sounds. Alternatively, the opposing wireless communication device 2 may periodically generate sounds of a fixed frequency range or pattern, and the collection unit 37 may detect these sounds. Furthermore, the sound information may be data showing the intensity and frequency spectrum of the sound wave itself, or it may be data in a processed form, such as the result of estimating the angle of arrival using a microphone array.

[0025] The wireless communication device 3 may have the configuration shown in Figure 2, or it may have a configuration in which the signal processing unit 32 is divided among the devices, such as the CU (Central Unit), DU (Distributed Unit), and RU (Radio Unit) in 5G NR (New Radio), or the signal processing unit 32 may be consolidated into one of the devices, such as the wireless communication device 3 or the control device 4.

[0026] The control device 4 comprises a transmission unit 41, a signal processing unit 42, a storage unit 43, an estimation / prediction unit 44, and a control unit 45. The transmission unit 41 is a functional unit that transmits signals to the wireless communication device 3, a higher-level device on the network (not shown), another control device 4, etc. The signal processing unit 42 is a functional unit that performs signal processing related to wireless communication. The signal processing unit 42 receives the transmission signal from the opposing wireless communication device 2 output by the wireless communication device 3 from the transmission unit 41 and obtains data from the input transmission signal. The signal processing unit 42 also transmits a transmission signal containing the data to be sent to the opposing wireless communication device 2 to the wireless communication device 3 via the transmission unit 41.

[0027] The memory unit 43 is a functional unit that stores information used in the processing of the estimation / prediction unit 44. The information used in the processing of the estimation / prediction unit 44 includes feedback information from the opposing wireless communication device 2 and sound information collected by the collection unit 37 of the wireless communication device 3. The feedback information indicates the transmission information for each type of beam in the beam sweep.

[0028] The estimation / prediction unit 44 is a functional unit that uses feedback information, sound information, and estimation models stored in the memory unit 43 to estimate or predict, according to the purpose of control, the propagation environment between the opposing wireless communication device 2 and the wireless communication device 3, such as shielding and reflection, the future communication quality of wireless communication between the opposing wireless communication device 2 and the wireless communication device 3, and the probability of the opposing wireless communication device 2 being located within the communication area of ​​the wireless communication device 3 in the future, or the probability of being located within the area. The control unit 45 controls the wireless communication between the opposing wireless communication device 2 and the wireless communication device 3 based on the estimation or prediction results of the estimation / prediction unit 44. For example, the control unit 45 controls the wireless communication device 3 to perform a beam sweep, switches the wireless communication device 3 to which the opposing wireless communication device 2 is connected, and performs sleep control of the wireless communication device 3.

[0029] The wireless communication device 3 may also include some or all of the memory unit 43, estimation / prediction unit 44, and control unit 45.

[0030] Figure 3 is a flowchart showing an example of wireless control of the wireless communication device 3 and control device 4 according to this embodiment. For example, each of the multiple wireless communication devices 3 performs the processing in steps S11 to S13, and the control device 4 performs the processing in steps S14 to S18 for each wireless communication device 3.

[0031] First, the wireless communication device 3 transmits a reference signal using a beam sweep (step S11). The opposing wireless communication device 2 acquires transmission information such as received signal strength, signal-to-noise power ratio, received timestamp, propagation path information, and beam index based on the reference signal received by each type of beam during the beam sweep. The received timestamp indicates the time when the opposing wireless communication device 2 received the reference signal. A notification unit (not shown) of the opposing wireless communication device 2 transmits feedback information, which includes the transmission information for each beam and the transmission timestamp, to the wireless communication device 3 (step S12). The transmission timestamp is the time when the feedback information from the opposing wireless communication device 2 was transmitted. The signal processing unit 32 of the wireless communication device 3 outputs the feedback information received from the opposing wireless communication device 2 to the transmission unit 31.

[0032] In parallel with the processing in steps S11 to S12, the acquisition unit 37 of the wireless communication device 3 acquires ambient sound information (step S13). The acquisition unit 37 outputs the acquired sound information to the transmission unit 31. The transmission unit 31 of the wireless communication device 3 transmits the feedback information received from the signal processing unit 32 and the sound information received from the acquisition unit 37 to the control device 4. The signal processing unit 42 of the control device 4 stores the feedback information and sound information received by the transmission unit 41 from the wireless communication device 3 in the storage unit 43 (step S14).

[0033] Next, the estimation / prediction unit 44 of the control device 4 estimates or predicts the propagation environment between the opposing wireless communication device 2 and the wireless communication device 3, such as shielding and reflection, the future communication quality of the wireless communication between the opposing wireless communication device 2 and the wireless communication device 3, and the area-bound probability of the opposing wireless communication device 2, based on the feedback information and sound information stored in the memory unit 43 and the estimation model (step S15). Machine learning is used for the estimation model. For example, the estimation model takes as input one or more of the received signal strength, signal-to-noise power ratio, and propagation path information arranged in time series or predetermined beam order based on the reception timestamp, transmission timestamp, or beam index of the feedback information, and time-series sound data indicated by the sound information, and outputs the propagation environment between the opposing wireless communication device 2 and the wireless communication device 3, a numerical value indicating the future communication quality of the wireless communication between the opposing wireless communication device 2 and the wireless communication device 3, and the area-bound probability of the opposing wireless communication device 2. In addition, a learning period may be provided before or during operation to perform machine learning on the estimation model. In this case, the control device 4 receives training data indicating the correct propagation environment, future communication quality, and whether or not the opposing wireless communication device 2 is within the area, corresponding to the feedback information and sound information. The estimation / prediction unit 44 uses the feedback information, sound information, and training data to machine-learn an estimation model.

[0034] In step S15, the control unit 45 determines whether control is necessary based on the estimated result information, which is the result estimated or predicted by the estimation / prediction unit 44 (step S16). Specifically, for example, the control unit 45 determines that control is necessary if it is predicted that after a predetermined time, the line of sight between the opposing wireless communication device 2 and the wireless communication device 3 will be non-line of sight due to fixed or variable shielding, if it is predicted that the received signal strength or signal-to-noise power ratio, etc., after a predetermined time will be below a predetermined value, or if the probability of the opposing wireless communication device 2 being within the area after a predetermined time is below a predetermined value. The control unit 45 may also determine that control is necessary if the difference between the predicted received signal strength or signal-to-noise power ratio, etc., after a predetermined time between the opposing wireless communication device 2 and the wireless communication device 3 to which the opposing wireless communication device 2 is currently connected, and the predicted received signal strength or signal-to-noise power ratio after a predetermined time when the opposing wireless communication device 2 is connected to another wireless communication device 3, exceeds a predetermined value.

[0035] If the control unit 45 determines that control is necessary (step S16: YES), it performs control based on the estimated result information obtained in step S15 (step S17). For example, the control unit 45 selects a beam that the wireless communication device 3 will use for data communication with the opposing wireless communication device 2 and instructs the opposing wireless communication device 2 to use the selected beam. Specifically, for example, it may select a beam in the direction in which the highest communication quality is predicted to be achieved after a predetermined time, or it may select a beam in the direction in which a line of sight from the wireless communication device 3 to the opposing wireless communication device 2 is predicted to be achieved after a predetermined time. The control unit 45 may also perform control to switch the wireless communication device 3 to which the opposing wireless communication device 2 is connected. Specifically, for example, it may switch the wireless communication device 3 to which the highest communication quality of wireless communication with the opposing wireless communication device 2 is predicted to be achieved after a predetermined time, or it may switch the wireless communication device 3 to which a line of sight with the opposing wireless communication device 2 is predicted to be achieved after a predetermined time. Furthermore, the control unit 45 may put the wireless communication device 3 to sleep after a predetermined time if the probability of the opposing wireless communication device 2 being within the communication area of ​​the wireless communication device 3 to which it is currently connected becomes close to zero or less after a predetermined time, or if it is predicted that the device will not be within the area. In addition, the control unit 45 may set the beam search range of the wireless communication device 3 to a range that includes the beam direction in which the communication quality is predicted to be higher than a threshold.

[0036] The wireless communication device 3 or the opposing wireless communication device 2 performs data communication according to the control of the control unit 45 of the control device 4 (step S18). For example, if the control unit 45 of the control device 4 instructs the wireless communication device 3 to use a beam for data communication, the beam control unit 33 of the wireless communication device 3 adjusts the beam of the transmitting and receiving unit 34 to form the instructed beam. As a result, the wireless communication device 3 performs wireless communication with the opposing wireless communication device 2 using the beam selected by the control unit 45 of the control device 4. Also, when the control unit 45 of the control device 4 switches the connection destination of the opposing wireless communication device 2, it transmits connection switching information to the opposing wireless communication device 2 indicating the wireless communication device 3 that will be the connection destination after the connection switch. When the opposing wireless communication device 2 receives the connection switching information via the wireless communication device 3, it switches its connection from the currently connected wireless communication device 3 to the destination wireless communication device 3 indicated by the connection switching information. Alternatively, the control unit 45 of the control device 4 may notify either or both the wireless communication device 3 to which the opposing wireless communication device 2 is currently connected and the destination wireless communication device 3 after the connection switch. The currently connected wireless communication device 3 and the wireless communication device 3 to be connected after the connection switch work in coordination to switch the connection destination of the opposing wireless communication device 2. Also, if the control unit 45 of the control device 4 instructs the wireless communication device 3 to sleep, the wireless communication device 3 will enter a sleep state for a predetermined time. Furthermore, if the control unit 45 of the control device 4 instructs the wireless communication device 3 to specify a beam search range, the beam control unit 33 of the wireless communication device 3 will adjust the beam of the transmitting and receiving unit 34 to form a beam within the specified beam search range.

[0037] Furthermore, if the control unit 45 of the control device 4 determines that control is unnecessary (step S16: NO), it will continue the current data communication without performing any control based on the estimated result information obtained in step S15 (step S18). After the processing in step S18, the wireless communication system 1 repeats the processing from step S11.

[0038] Figure 4 is a sequence diagram showing an example of operation of the wireless communication system 1 according to this embodiment. Figure 4 shows an example sequence when switching the destination wireless communication device 3 of the opposing wireless communication device 2 based on estimated result information. Here, the two wireless communication devices 3 are referred to as wireless communication devices 3-1 and 3-2. In this sequence example, the opposing wireless communication device 2 is in a state where it is connected to wireless communication device 3-1 and communicating, and then switches its destination to wireless communication device 3-2 based on estimated result information and begins communicating.

[0039] The opposing wireless communication device 2 and the wireless communication device 3-1 are communicating (step S21). Specifically, the transmission unit 31 of the wireless communication device 3-1 converts the transmission data received from the control device 4 or a higher-level device into transmission signals from each antenna element 35. The transmitting / receiving unit 34 adjusts the phase and amplitude of each transmission signal using weights instructed by the beam control unit 33 to form a beam and transmits wireless signals from the antenna elements 35. The transmitting / receiving unit 34 of the wireless communication device 3-1 also adjusts the phase and amplitude of the wireless signals received by each antenna element 35 from the opposing wireless communication device 2 using weights instructed by the beam control unit 33 and combines the adjusted wireless signals. The signal processing unit 32 acquires the signal transmitted by the opposing wireless communication device 2 from the combined received signal. The transmission unit 31 outputs the signal acquired by the signal processing unit 32 to the higher-level device or the control device 4.

[0040] The control device 4 transmits a measurement instruction control signal to the opposing wireless communication device 2 via the wireless communication device 3-1 at regular intervals or at instructed timings (step S22). That is, the control unit 45 of the control device 4 outputs a measurement instruction control signal at regular intervals or at instructed timings, and the signal processing unit 42 outputs a measurement instruction control signal from the transmission unit 41 to the wireless communication device 3-1. The wireless communication device 3-1 transmits the measurement instruction control signal received from the control device 4 wirelessly. The opposing wireless communication device 2 starts measurement using the reference signal according to the received measurement instruction control signal.

[0041] Each of the wireless communication devices 3-1 and 3-2 transmits a reference signal wirelessly while performing a beam sweep to change the beam over time (steps S23 and S24). At this time, as shown in the example sequence in Figure 4, the beam sweep may be performed separately over time among multiple wireless communication devices 3, the wireless frequency on which the reference signal is transmitted may be different for each wireless communication device 3, or the beam sweep may be performed simultaneously among multiple wireless communication devices 3 using orthogonal signals. The nth beam in the beam sweep is denoted as Beam#n, and the reference signal transmitted by Beam#n is denoted as reference signal#n. Here, n is an integer between 1 and N, and N is an integer of 2 or greater. The beam control units 33 of each of the wireless communication devices 3-1 and 3-2 output the reference signal#n generated by the signal processing unit 32 to the transmitting / receiving unit 34 and control it to form Beam#n. The transmitting / receiving unit 34 transmits the reference signal#n by Beam#n formed by the antenna element 35.

[0042] The opposing wireless communication device 2 receives reference signals #1 to #N transmitted from wireless communication devices 3-1 and 3-2 via Beam #1 to #N, respectively. Based on the reference signal #n received from each of wireless communication devices 3-1 and 3-2 via Beam #n, the opposing wireless communication device 2 calculates transmission information such as received signal strength, signal-to-noise power ratio, received timestamp, and propagation path information. The opposing wireless communication device 2 sends a report signal to wireless communication device 3-1 containing the transmission information calculated for each of Beam #1 to #N, the transmission timestamp, the device identification information of the wireless communication device 3 that transmitted the reference signal, and the device identification information of the opposing wireless communication device 2 (step S25). The transmitting and receiving unit 34 of wireless communication device 3-1 synthesizes the signals received by each antenna element 35 according to the control from the beam control unit 33 to generate a received signal. The signal processing unit 32 obtains the report signal transmitted by the opposing wireless communication device 2 from the received signal.

[0043] The wireless communication device 3-1 may specify the feedback timing for each beam of the opposing wireless communication device 2 by setting it as a reference signal. The opposing wireless communication device 2 transmits a report signal at the specified feedback timing. The beam control unit 33 of the wireless communication device 3-1 then controls the transmitting and receiving unit 34 to sweep the received beam and receive the report signal, similar to the beam sweep when transmitting the reference signal. Alternatively, the opposing wireless communication device 2 may transmit a report signal containing feedback information that aggregates the transmission information of each beam at the feedback timing of the beam with the highest received signal strength.

[0044] The transmission unit 31 of the wireless communication device 3-1 adds sound information collected by the collection unit 37 during beam sweeping to the report signal received from the opposing wireless communication device 2 and transmits it to the control device 4 (step S26). The signal processing unit 42 of the control device 4 receives the report signal from the wireless communication device 3-1 via the transmission unit 41. The signal processing unit 42 obtains feedback information and sound information, the device ID of the wireless communication device 3-1, and the device ID of the opposing wireless communication device 2 from the report signal, and writes this information linked together to the storage unit 43. The device ID is information that identifies each device. The control unit 45 of the control device 4 may also obtain sound information from other wireless communication devices 3 by sending instructions to other wireless communication devices 3. The control unit 45 links the received sound information with the device ID of the other wireless communication devices 3 and writes it to the storage unit 43. The estimation / prediction unit 44 uses the feedback information and sound information written to the memory unit 43, along with the prediction model, to estimate or predict the propagation environment between the opposing wireless communication device and each wireless communication device 3, the future communication quality of wireless communication between the opposing wireless communication device 2 and each wireless communication device 3, and the probability of the wireless communication device 3 being within the area (step S27). The estimation / prediction unit 44 outputs estimation result information indicating the estimation or prediction result to the control unit 45.

[0045] If the control unit 45 determines that control is necessary based on the estimated result information, it determines the content of that control. The control unit 45 generates a control signal to control the wireless communication device 3 or the opposing wireless communication device 2 according to the determined control content and outputs it to the wireless communication device 3 from the transmission unit 41. Here, the control unit 45 decides to switch the connection destination of the opposing wireless communication device 2 from wireless communication device 3-1 to wireless communication device 3-2 based on the estimated result information (step S28). The control unit 45 transmits a control signal to the current connection destination, wireless communication device 3-1, and the connection destination after the switch, wireless communication device 3-2 (step S29). The control signal is set to the device ID of the opposing wireless communication device 2, the device ID of the original wireless communication device 3-1, and the device ID of the destination wireless communication device 3-2. The wireless communication device 3-1 transfers any data that could not be transmitted to the opposing wireless communication device 2 due to the connection destination switch to the destination wireless communication device 3-2 (step S30).

[0046] The control unit 45 of the control device 4 transmits a switching instruction control signal to the opposing wireless communication device 2 via the source wireless communication device 3-1 (step S31). The switching instruction control signal is set with the device ID of the source wireless communication device 3-1 and the device ID of the destination wireless communication device 3-2. The opposing wireless communication device 2 performs the connection switching process to wireless communication device 3-2 according to the received switching instruction control signal. That is, the opposing wireless communication device 2 performs synchronization and connection establishment processing with the destination wireless communication device 3-2 indicated by the switching instruction control signal (step S32). Once the wireless communication device 3-2 has established a connection with the opposing wireless communication device 2, it notifies the control device 4 of the connection establishment and establishes a connection between the opposing wireless communication device 2 and the control device 4 (step S33). The opposing wireless communication device 2 can continue communication after switching the connection destination to wireless communication device 3-2 (step S33).

[0047] For example, in step S28 of Figure 4, the control unit 45 decides that the beam used by the wireless communication device 3-1 to communicate data signals to the opposing wireless communication device 2 should be Beam#x (where x is an integer between 1 and N). The control unit 45 transmits a control signal specifying Beam#x to the wireless communication device 3-1. The signal processing unit 32 of the wireless communication device 3-1 outputs the control signal received via the transmission unit 31 to the beam control unit 33. The beam control unit 33 controls the transmitting and receiving unit 34 to form Beam#x when transmitting a wireless signal to the opposing wireless communication device 2 according to the received control signal.

[0048] Furthermore, for example, in step S28 of Figure 4, suppose the control unit 45 determines the beam search range of the wireless communication device 3-i (i=1, 2). The control unit 45 transmits a control signal to the wireless communication device 3-i indicating the determined beam search range. The beam control unit 33 of the wireless communication device 3-i controls the transmitting and receiving unit 34 to switch and form the beams of each Beam#x included in the beam search range indicated by the received control signal during beam searching.

[0049] For example, in step S28 of Figure 4, suppose the control unit 45 of the control device 4 decides to put the wireless communication device 3-i (i=1, 2) into sleep mode from time t1. At time t1, the control unit 45 transmits a control signal to the wireless communication device 3-i instructing it to sleep. The wireless communication device 3-i enters a sleep state for a predetermined time after receiving the control signal. Alternatively, the control unit 45 of the control device 4 may transmit a control signal to the wireless communication device 3-i instructing it to sleep from time t1. The wireless communication device 3-i enters a sleep state for a predetermined time from time t1 according to the received control signal. The control unit 45 of the control device 4 may also transmit a control signal to the wireless communication device 3-i instructing it to end the sleep mode.

[0050] Up to this point, the description has assumed that the wireless communication device 3 performs a beam sweep and controls the device using feedback information from the opposing wireless communication device 2. However, the same control is possible even when the downlink and uplink directions are reversed, and this is included in the embodiments of the present invention. In other words, the opposing wireless communication device 2 has the same functions as the beam control unit 33, the transmitting / receiving unit 34, the storage unit 43, the estimation / prediction unit 44, and the control unit 45. The opposing wireless communication device 2 may perform a beam sweep, estimate or predict the propagation environment such as shielding and reflection and future communication quality based on feedback information and sound information from the wireless communication device 3, and control the device based on the results of the estimation or prediction.

[0051] Furthermore, the estimation / prediction unit 44 of the control device 4 may use feedback information from other opposing wireless communication devices 2 in addition to the feedback information from the opposing wireless communication device 2 to be estimated or predicted (hereinafter referred to as the target opposing wireless communication device 2) to estimate or predict the propagation environment between the wireless communication device 3 and the target opposing wireless communication device 2, and the future communication quality of the wireless communication between the wireless communication device 3 and the target opposing wireless communication device 2.

[0052] The functions of the control device 4 in the above-described embodiment may be implemented using a computer. In that case, the functions of the estimation / prediction unit 44 and the control unit 45 may be implemented by recording a program for implementing the functions of the estimation / prediction unit 44 and the control unit 45 on a computer-readable recording medium, loading the program recorded on this recording medium into a computer system, and executing it. The program may also be provided via a network. Here, "computer system" includes hardware such as the OS and peripheral devices. "Computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into a computer system. Furthermore, "computer-readable recording medium" may also include those that dynamically hold programs for a short period of time, such as communication lines used when transmitting programs via networks such as the Internet or communication lines such as telephone lines, and those that hold programs for a certain period of time, such as volatile memory inside a computer system that acts as a server or client in such cases. The above-mentioned program may only implement a part of the functions described above, and may also be able to implement the above-mentioned functions in combination with a program already recorded in the computer system.

[0053] The control device 4 may be implemented by multiple computer devices connected to a network. In this case, it is arbitrary which of these multiple computer devices implements each functional unit of the control device 4. Furthermore, the same functional unit may be implemented by multiple computer devices.

[0054] Figure 5 is a device configuration diagram showing an example of the hardware configuration of the control device 4. The control device 4 comprises a processor 71, a storage unit 72, a communication interface 73, and a user interface 74. The processor 71 is a central processing unit that performs calculations and control. The processor 71 is, for example, a CPU (central processing unit) or a GPU (Graphics Processing Unit). The processor 71 realizes the functions of the estimation / prediction unit 44 and the control unit 45 by reading and executing programs from the storage unit 72. The storage unit 72 further has a work area for when the processor 71 executes various programs. The communication interface 73 connects to other devices so that they can communicate with each other. The communication interface 73 realizes the transmission unit 41 and the signal processing unit 42. The user interface 74 is an input device such as a keyboard, a pointing device (mouse, tablet, etc.), buttons, a touch panel, or a display device such as a display. Human operations are input through the user interface 74.

[0055] Furthermore, all or part of the functions of the estimation / prediction unit 44 and the control unit 45 may be implemented using hardware such as an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field Programmable Gate Array).

[0056] According to this embodiment, in a high-frequency band wireless communication system, control becomes possible based on understanding both the line-of-sight and non-line-of-sight environments surrounding the wireless communication device, thereby improving communication quality and connectivity.

[0057] In particular, in the high-frequency band, there is a tendency to use narrow beams to ensure high beam gain, and it is expected that the resolution of communication radio wave sensing using beam sweeps will be higher. Furthermore, the sensing information obtained from communication radio wave sensing is expected to have a higher correlation with communication quality compared to sensing outside of wireless communication. On the other hand, because radio waves have strong directional properties and are easily affected by shielding, it is difficult to understand the environment beyond the line of sight. Focusing on these points, by combining communication radio wave sensing using beam sweeps, which is expected to enable high-precision understanding of the line-of-sight environment while keeping the size and cost of wireless communication equipment down, with sound sensing, which is expected to enable understanding of the environment beyond the line of sight, it is possible to efficiently improve communication quality.

[0058] According to the embodiment described above, the wireless communication system comprises one or more first wireless communication devices and one or more second wireless communication devices. For example, the first wireless communication device corresponds to the wireless communication device 3 of the embodiment, and the second wireless communication system corresponds to the opposing wireless communication device 2 of the embodiment. The first wireless communication device comprises a wireless communication unit, a beam control unit, and an acquisition unit. The wireless communication unit forms a beam and communicates wirelessly with the second wireless communication device. For example, the wireless communication unit corresponds to the transmitting / receiving unit 34 of the embodiment. The beam control unit controls the beam formed by the wireless communication unit. The acquisition unit acquires sound information picked up from around its own device. The second wireless communication device receives reference signals transmitted by the wireless communication unit using multiple types of beams under the control of the beam control unit, and includes a notification unit that notifies transmission information indicating information regarding the wireless transmission of the received reference signals. The first wireless communication device or a control device connected to the first wireless communication device comprises an estimation / prediction unit and a control unit. The estimation and prediction unit uses the transmission information notified by the notification unit and the sound information acquired by the acquisition unit to estimate or predict the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device will be within the communication area of ​​the first wireless communication device. The control unit controls the wireless communication between the first wireless communication device and the second wireless communication device based on the estimation or prediction results by the estimation and prediction unit. For example, the control unit instructs the first wireless communication device on the beam, sleep, or beam search range to be formed based on the estimation or prediction results. Alternatively, the control unit instructs the first wireless communication device to switch to the second wireless communication device based on the estimation or prediction results.

[0059] The transmission information may include one or more of the received power, communication quality, communication distance, and transmission path information of the radio that transmitted the reference signal, as well as one or more of the reception timing of the reference signal and identification information of the beam used to transmit the reference signal. The propagation environment may also include shielding or reflection of the radio signal between the first radio communication device and the second radio communication device.

[0060] While embodiments of the present invention have been described above with reference to the drawings, it is clear that the above embodiments are merely illustrative examples of the present invention, and the present invention is not limited to these embodiments. Therefore, additions, omissions, substitutions, and other modifications of components are permitted without departing from the technical concept and scope of the present invention. [Explanation of Symbols]

[0061] 1... Wireless communication system, 2... Opposite wireless communication device, 3, 3-1, 3-2... Wireless communication device, 4... Control device, 5... Fixed shield, 6... Variable shield, 31... Transmission unit, 32... Signal processing unit, 33... Beam control unit, 34... Transmit / receive unit, 35... Antenna element, 36... Microphone, 37... Collection unit, 41... Transmission unit, 42... Signal processing unit, 43... Memory unit, 44... Estimation / prediction unit, 45... Control unit, 71... Processor, 72... Memory unit, 73... Communication interface, 74... User interface

Claims

1. A wireless communication system comprising one or more first wireless communication devices and one or more second wireless communication devices, The first wireless communication device is A wireless communication unit that forms a beam and communicates wirelessly with the second wireless communication device, A beam control unit that controls the beam formed by the wireless communication unit, An acquisition unit that acquires sound information collected from the surroundings of the device, Equipped with, The second wireless communication device is The beam control unit controls the wireless communication unit to receive reference signals transmitted by each of several types of beams, and the unit also includes a notification unit that notifies transmission information indicating information regarding the wireless transmission of the received reference signals. The first wireless communication device or the control device connected to the first wireless communication device is An estimation and prediction unit that estimates or predicts the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device, using the transmission information notified by the notification unit and the sound information acquired by the acquisition unit. The system includes a control unit that controls wireless communication between the first wireless communication device and the second wireless communication device based on the estimation or prediction results of the estimation / prediction unit, Wireless communication system.

2. The control unit instructs, based on the estimation or prediction results by the estimation and prediction unit, to set the beam formed by the first wireless communication device, the sleep time of the first wireless communication device, the beam search range of the first wireless communication device, or to switch the first wireless communication device to which the second wireless communication device is connected. The wireless communication system according to claim 1.

3. The transmission information includes one or more of the received power, communication quality, communication distance, and transmission path information of the radio that transmitted the reference signal, and one or more of the reception timing of the reference signal and identification information of the beam used to transmit the reference signal. The wireless communication system according to claim 1 or claim 2.

4. The propagation environment includes shielding or reflection of radio signals between the first wireless communication device and the second wireless communication device. A wireless communication system according to either claim 1 or claim 2.

5. A control device in a wireless communication system having one or more first wireless communication devices, one or more second wireless communication devices, and a control device for controlling the first wireless communication devices, A unit that acquires transmission information indicating information regarding wireless transmission when the second wireless communication device receives a reference signal transmitted from the first wireless communication device using multiple types of beams, and sound information picked up around the first wireless communication device, and estimates or predicts the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device, using the acquired transmission information and sound information, A control unit controls wireless communication between the first wireless communication device and the second wireless communication device based on the estimation or prediction results by the estimation and prediction unit, A control device equipped with the following features.

6. A wireless communication method in a wireless communication system having one or more first wireless communication devices and one or more second wireless communication devices, The first wireless communication device, A transmission step in which a wireless reference signal is transmitted using multiple types of beams, An acquisition step to acquire sound information collected from the surroundings of the device, The second wireless communication device, A notification step includes receiving a reference signal transmitted from the first wireless communication device by each of several types of beams, and notifying transmission information indicating information regarding the wireless transmission of the received reference signal, The first wireless communication device or the control device connected to the first wireless communication device, An estimation and prediction step in which, using the transmission information notified in the notification step and the sound information acquired in the acquisition step, an estimation and prediction step is made to estimate or predict the propagation environment between the first wireless communication device and the second wireless communication device, the future communication quality between the first wireless communication device and the second wireless communication device, or the probability that the second wireless communication device is located within the communication area of ​​the first wireless communication device. A control step in which the first wireless communication device or the control device controls wireless communication between the first wireless communication device and the second wireless communication device based on the result of the estimation or prediction in the estimation and prediction step, A wireless communication method having

7. Computers, A program for causing the control device to function as described in claim 5.

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