Information processing device, phase error amount estimation method, and phase error amount estimation program

Abstract

Provided is an information processing device for estimating a phase error amount on the basis of non-linear temperature dependency of an antenna. The information processing device comprises: an acquisition unit that acquires temperature data from a temperature sensor provided to each of a plurality of antennas; an estimation unit that estimates a phase error amount for each antenna by inputting the temperature data acquired by the acquisition unit to a learning model provided for each antenna, the learning model having been trained by using the temperature data as an explanatory variable and a phase error occurring in communication of the antenna at a temperature indicated by the temperature data as an objective variable; and an output unit that outputs, in association with each antenna, the phase error amount estimated by the estimation unit.

Description

Information Processing Apparatus, Phase Error Amount Estimation Method, and Phase Error Amount Estimation Program

[0001] The present disclosure relates to a communication system.

[0002] There is a technique for obtaining the temperature of each of a plurality of antennas and switching the antenna used for communication when the temperature of the antenna is equal to or higher than a second temperature lower than a first temperature at which the use of the antenna is stopped (for example, Patent Document 1). There is also known an antenna device that includes a plurality of antenna elements, obtains temperature information indicating the temperature of each of a plurality of signal sources, calculates a phase compensation amount corresponding to the temperature distribution between the plurality of signal sources based on the temperature information, and outputs a locally oscillated signal after phase compensation (for example, Patent Document 2).

[0003] Japanese Patent No. 7416085, Japanese Patent No. 7269973

[0004] An information processing apparatus according to one aspect includes an acquisition unit that acquires temperature data from temperature sensors provided in each of a plurality of antennas, and a learning model prepared for each antenna, which uses the temperature data as an explanatory variable and learns with the phase error that occurs in the communication of the antenna at the temperature indicated by the temperature data as an objective variable. An estimation unit that inputs the temperature data acquired by the acquisition unit and estimates the amount of phase error for each antenna, and an output unit that outputs the amount of phase error estimated by the estimation unit in association with each antenna.

[0005] In the information processing apparatus described above, the plurality of antennas may be antennas that form a phased array antenna that performs beamforming and communicates with a terminal.

[0006] Furthermore, in the above-mentioned information processing device, multiple antennas transmit signals by beamforming with a phase corrected based on the phase error amount, and the information processing device includes a receiving unit that receives a feedback signal from a reference point that receives the signal, which is the phase error between the phase of the signal actually received at the reference point and the phase of the received signal that should be received at the reference point, and an adjustment unit that adjusts the parameters of the learning model using the phase error indicated by the feedback signal, and an estimation unit that estimates the phase error amount using the learning model adjusted by the adjustment unit.

[0007] Furthermore, one embodiment of the phase error estimation method involves a computer performing an acquisition step in which it acquires temperature data from temperature sensors provided on each of several antennas; an estimation step in which it inputs the temperature data acquired in the acquisition step to a learning model prepared for each antenna, which has been trained with temperature data as an explanatory variable and the phase error that occurs in the communication of the antenna when the temperature indicated by the temperature data is the objective variable, and estimates the phase error amount for each antenna; and an output step in which it outputs the phase error amount estimated in the estimation step, associated with each antenna.

[0008] Furthermore, one embodiment of the phase error amount estimation program provides a computer with an acquisition function that acquires temperature data from temperature sensors provided on each of several antennas, an estimation function that takes the temperature data acquired by the acquisition function as input to a learning model prepared for each antenna, which has been trained with temperature data as an explanatory variable and the phase error that occurs in the communication of the antenna when the temperature indicated by the temperature data is the objective variable, and estimates the phase error amount for each antenna, and an output function that outputs the phase error amount estimated by the estimation function in association with each antenna.

[0009] This is a schematic diagram showing an overview of a communication system including an information processing device. This is a block diagram showing an example of the configuration of the information processing device. This is a flowchart showing an example of the operation of the information processing device, specifically during estimation. This is a flowchart showing an example of the operation of the information processing device, specifically during retraining.

[0010] The following describes a communication system according to one embodiment, with reference to the drawings. <Problem>

[0011] Conventionally, it has been known that antenna characteristics change depending on the antenna temperature, affecting communication. Therefore, it is known to switch the antenna used depending on the antenna temperature, or to calculate a phase compensation amount based on the temperature distribution of multiple signal sources to correct the phase error. Conventional calculations of phase error are performed using fixed mathematical formulas, which has the problem of lacking flexibility, and the calculated phase error amount does not allow for accurate beamforming. Therefore, the objective of this embodiment is to provide an information processing device, a phase error amount estimation method, and a phase error amount estimation program that can estimate the phase error amount based on the nonlinear temperature dependence of the antenna.

[0012] <Configuration> Figure 1 is a system diagram showing an example configuration of a communication system including an information processing device. The communication system includes a terminal 10, a wireless base station 200 that communicates with the terminal, and an information processing device 100 that communicates with the wireless base station 200. The information processing device 100 is connected to each wireless base station 200 via a network 300 so as to be able to communicate. The wireless base station 200 is equipped with a phased array antenna that forms antenna directivity (beamforming) toward the terminal 10 and performs communication. The phased array antenna is equipped with multiple antennas to realize MIMO (Multiple Input Multiple Output). This enables beamforming and comfortable communication with the terminal (without interfering with communication with other terminals). Each of the multiple antennas is provided with a temperature sensor, and the temperature measured by the temperature sensor is transmitted sequentially to the information processing device 100.

[0013] In the example shown in Figure 1, the wireless base station 200a is equipped with four antennas 220a to 223a, and each antenna 220a to 223a is individually associated with a temperature sensor 230a to 233a. The phase of each antenna 220a to 223a is corrected by a phase shifter 240a and a phase correction unit 250a. Note that in Figure 1, the reference numerals for antennas 221a, 222a and temperature sensors 231a and 232a have been omitted for the sake of clarity in the drawing. Note that the number of antennas is not limited to four; any number of antennas may be used. The wireless base station 200a performs beamforming 210a to communicate with terminals 10a and 10b that are within the range of each beamforming. The wireless base station 200a transmits temperature information, which indicates the temperature measured by the temperature sensors 230a to 233a, to the information processing device 100, associating it with information indicating the antennas 220a to 223a on which each temperature sensor 230a to 233 is located.

[0014] Similarly, the wireless base station 200b is equipped with four antennas 220b to 223b, and each antenna 220b to 223b is individually associated with a temperature sensor 230b to 233b. The phase of each antenna 220b to 223b is corrected by a phase shifter 240b and a phase correction unit 250b. In Figure 1, the reference numerals for antennas 221b, 222b and temperature sensors 231b and 232b have been omitted for the sake of clarity in the drawing. Note that the number of antennas is not limited to four; any number of antennas may be used. The wireless base station 200b performs beamforming 210b to communicate with terminals 10c and 10d that are within the range of each beamforming. The wireless base station 200b transmits temperature information, which indicates the temperature measured by temperature sensors 230b to 233b, to the information processing device 100, associating it with information indicating the antennas 220b to 223b on which each temperature sensor 230b to 233 is located.

[0015] Hereafter, unless otherwise specified, the following terms will be used: wireless base station 200, antenna 220, temperature sensor 230, phase correction unit 250, and terminal 10.

[0016] The information processing device 100 estimates the current phase error amount using a learning model that has learned the relationship between temperature and phase error based on the temperature of each of the multiple antennas installed at each wireless base station 200, and transmits this information to each wireless base station 200. Based on the transmitted phase error amount, each wireless base station 200 uses a phase correction unit 250 to correct the phase error of each antenna 220, performs beamforming based on the corrected phase, and communicates with each terminal 10. By using the learning model, the temperature dependence, which has a nonlinear relationship with the antenna's phase error, can be corrected with high accuracy.

[0017] The communication system may be a communication system that performs communication in accordance with 4G or 5G communication standards, but is not limited to these; it may also be a communication system that conforms to 6G or CDMA communication standards. Furthermore, the wireless base station 200 may be a RU (Radio Unit) or DU (Distributed Unit) in 5G communication, but is not limited to these.In addition, although the information processing device 100 is shown as an external device that is communicably connected to each wireless base station 200 via the network 300, the information processing device 100 may be built into the wireless base station 200.Furthermore, the information processing device 100 may be a DU or CU (Central Unit) in the fifth generation communication standard.

[0018] The information processing device 100 according to this embodiment will be described in detail below.

[0019] Figure 2 is a block diagram showing an example configuration of the information processing device 100. As shown in Figure 2, the information processing device 100 comprises a communication unit 110, a control unit 130, and a storage unit 140, and may also include an input unit 120 and an output unit 150. The information processing device 100 is a computer system that estimates the phase error of each antenna based on the temperature measured by a temperature sensor attached to the antenna. The information processing device 100 may be implemented by a server device, a PC, etc., but is not limited to these.

[0020] The communication unit 110 is a communication interface that has the function of communicating with external devices of the information processing device 100 and with the network 300. The communication unit 110 communicates with an external device, for example, a radio base station 200, to exchange information. For example, the communication unit 110 receives temperature information indicating the temperature of each antenna of the radio base station 200 transmitted from the radio base station 200 and transmits it to the control unit 130. The communication unit 110 also receives feedback signals transmitted from the radio base station 200 and transmits them to the control unit 130. Details of the feedback signals will be described later.

[0021] The input unit 120 is an input interface that receives input from the operator of the information processing device 100. The input unit 120 may be implemented as a keyboard, mouse, microphone, etc., but is not limited to these. The input unit 120 transmits the received input content to the control unit 130.

[0022] The control unit 130 is a processor that controls each part of the information processing device 100. The control unit 130 uses various data stored in the storage unit 140 and executes various programs to realize the functions that the information processing device 100 should perform. The control unit 130 estimates the phase error caused by the temperature of each antenna provided on the wireless base station 200 and transmits this to the wireless base station 200.

[0023] The control unit 130 functions as an acquisition unit 131, an estimation unit 132, and an output unit 133. Alternatively, the control unit 130 may function as an adjustment unit 134.

[0024] The acquisition unit 131 acquires temperature information for each antenna of the wireless base station 200, which has been received by the communication unit 110 and transmitted from the wireless base station 200. This temperature information is temperature information measured by a temperature sensor 230 provided on each antenna, and is information that associates an identifier indicating the antenna with the temperature measured by the temperature sensor 230 provided on that antenna, and may be a temperature table for all antennas provided on the wireless base station 200. The acquisition unit 131 transmits the acquired temperature information to the estimation unit 132.

[0025] The estimation unit 132 estimates the amount of phase error occurring in the corresponding antenna based on the temperature information acquired by the acquisition unit 131. The estimation unit 132 estimates the amount of phase error of the antenna by inputting the corresponding temperature to the learning model 141 corresponding to the antenna identifier associated with the temperature transmitted from the acquisition unit 131. The estimation unit 132 transmits the information indicating the estimated amount of phase error of the antenna to the output unit 133, associating it with the corresponding antenna identifier.

[0026] The function of the estimation unit 132 may be implemented by a RIC (RAN Intelligent Controller).

[0027] The output unit 133 outputs the phase error amount estimated by the estimation unit 132, associating it with information indicating the antenna to which the phase error amount corresponds. The output unit 133 associates the phase error amount estimated by the estimation unit 132 with the antenna identifier to which the temperature used to estimate the phase error amount was associated, and outputs (transmits) this information via the communication unit 110 to the radio base station 200 that transmitted the temperature information. As a result, the phase correction unit 250 of the radio base station 200 can correct the phase error of the antenna indicated by the antenna identifier, thereby achieving accurate beamforming.

[0028] The adjustment unit 134 adjusts the parameters of the learning model 141. The adjustment unit 134 receives a feedback signal from the radio base station 200 that indicates the phase error between the phase at the reference point when the signal transmitted by beamforming, performed after the phase correction unit 250 of the radio base station 200 corrected the phase based on the estimated error amount estimated by the estimation unit 132, was received, and the phase if beamforming had been performed correctly at the reference point. This feedback signal is information transmitted from the reference point to the radio base station 200. Based on this feedback signal, the adjustment unit 134 adjusts the parameters of the learning model 141. The adjustment of the parameters of the learning model 141 may be achieved by relearning or reinforcement learning the phase error amount of each antenna 220 of the radio base station 200, or by relearning the relationship between the temperature of each antenna and the phase error when the phase error was estimated. The feedback signal is generated based on the signal received by the reference point after beamforming has been performed, with the phase error estimated. However, since the antenna temperature does not change that rapidly, it is acceptable to use the temperature at the time the phase error was estimated. In this case, the temperature of each antenna's temperature sensor 230 is checked, and if there is a difference of more than a predetermined amount between the temperature at the time the phase error was estimated and the temperature at that time, it is not necessary to adjust the parameters of the learning model 141.

[0029] A reference point is a receiver whose location is known in advance by the radio base station and whose phase can be determined if correct beamforming is being performed. The receiver may be another radio base station, a user's smartphone or other terminal, or other communication device.

[0030] The following relationship exists between the phase of antenna i before correction and the feedback signal.

[0031]

[0032] θ ｉ θ is the phase of the antenna before correction. i2 is the phase of the corrected antenna, α indicates the value of the feedback gain, and e ｉThis is the difference between the estimated error and the actual error shown by the feedback signal. α is a coefficient that has been tuned to obtain a stable value through simulation.

[0033] The function of the adjustment unit 134 may be realized by the RIC.

[0034] The storage unit 140 is a storage medium that stores various programs and data required for the operation of the information processing device 100. The storage unit 140 may be implemented using an HDD (Hard Disk Drive), SSD (Solid State Drive), flash memory, etc., but is not limited to these. The storage unit 140 may also be implemented using cloud storage accessible by the information processing device 100. The storage unit 140 may store a learning model 141 for each antenna (or for each type of antenna) that has learned the relationship between the antenna temperature and phase error. Since the temperature dependence differs depending on the shape and characteristics of the antenna, the learning model 141 may be provided according to the shape and characteristics of the antenna, and may be provided for all antennas of multiple (or all) wireless base stations 200 present in the communication system. The storage unit 140 may also store a program for estimating the phase error of the antenna using the learning model 141 and transmitting it to the wireless base station 200 having the corresponding antenna.

[0035] The output unit 150 is an output interface that outputs predetermined information according to instructions from the control unit 130. The output unit 150 may be implemented as a monitor or speaker, for example, but is not limited to these. The output unit 150 may display a numerical value indicating the estimated phase error amount according to instructions from the control unit 130.

[0036] The above is an example of the configuration of the information processing device 100.

[0037] As shown in FIG. 1, the wireless base station 200 includes a plurality of antennas 220, temperature sensors 230 associated with the respective antennas 220, a phase shifter 240, and a phase correction unit 250. Although not shown, the wireless base station 200 has functions equivalent to those of a base station that relays general inter-terminal communication, and communicates with the information processing device 100 to transmit the temperature information of each antenna, receives the amount of phase error estimated based on the temperature information from the information processing device 100, adjusts the phase of each antenna, performs beamforming, and communicates with each terminal 10. The phase correction unit 250 of the wireless base station adjusts the phase of the signal transmitted by the phase shifter 240 of the corresponding antenna 220 based on the transmitted phase error.

[0038] The phase correction unit 250 may correct the phase of each antenna 220 based on the following mathematical formula.

[0039]

[0040] In the above formula, ΔT is a value indicating the amount of temperature change from the reference, k is the temperature coefficient, φ0 is the phase shift amount at the reference temperature T0, and is a constant. f(T) is a correction amount based on non-linear temperature dependence, and is a static correction amount derived from the relationship between known temperature and phase error. g is the amount of phase error estimated by the information processing device 100 using the learning model 141. <Operation>

[0041] Hereinafter, the operation of the information processing device will be described. First, the operation at the time of estimating the phase error will be described using FIG. 3.

[0042] As shown in FIG. 3, the communication unit 110 of the information processing device 100 receives the temperature information of each antenna 220 from the wireless base station 200. The communication unit 110 transmits the received temperature information to the control unit 130, and the acquisition unit 131 of the control unit 130 acquires this (step S301). The acquisition unit 131 transmits the acquired temperature information to the estimation unit 132.

[0043] The estimation unit 132 estimates the phase error amount for the transmitted temperature information by using the learning model 141 corresponding to the identifier of the associated antenna (step S302). The estimation unit 132 transmits the estimated phase error amount to the output unit 133.

[0044] The output unit 133 transmits, via the communication unit 110, the transmitted phase error amount in association with the identifier of the corresponding antenna to the radio base station 200 (step S303). The phase correction unit 250 of the radio base station 200 controls the phase (phase shifter 240) of the signal to be transmitted based on the received phase error amount.

[0045] Next, the operation when adjusting the parameters of the learning model will be described with reference to FIG. 4.

[0046] As shown in FIG. 4, the communication unit 110 of the information processing apparatus 100 receives, from the radio base station 200, the feedback signal received by the radio base station 200 from the reference point (step S401). The communication unit 110 transmits the received feedback signal to the control unit 130.

[0047] The adjustment unit 134 of the control unit 130 adjusts the parameters of the learning model 141 based on the phase error indicated by the feedback signal (step S402).

[0048] The estimation unit 132 inputs the temperature of the antenna at the previous estimation to the learning model 141 adjusted by the adjustment unit 134, and re-estimates the phase error amount (step S403). The estimation unit 132 transmits the estimated phase error amount to the output unit 133.

[0049] The output unit 133 transmits the re-estimated phase error amount to the radio base station 200 via the communication unit 110 (step S404). As a result, the radio base station 200 can adjust the phase of each antenna more accurately and perform accurate beamforming.

[0050] Note that the processing shown in FIG. 4 may be stopped at the processing up to step S402, and the processing after step S403 may be applied to the estimation processing in subsequent times.

[0051] <Summary> According to the information processing device 100 of the above embodiment, the phase error amount can be estimated based on the temperature information of each antenna 220 of the wireless base station 200 using a learning model 141 that has learned the relationship between antenna temperature and phase error. As a result, the information processing device 100 can accurately estimate the phase error amount which has a nonlinear temperature dependence, and the wireless base station 200 can adjust the phase of the signal of each antenna based on the estimated accurate phase error amount, thereby performing accurate beamforming and enabling comfortable communication with the terminal 10.

[0052] <Supplement> The information processing device 100 according to the present invention is not limited to the embodiments shown above. Various modifications will be described below.

[0053] (1) In the above embodiment, the learning model 141 was a model that learned the relationship between temperature and phase error. However, antenna performance does not depend only on temperature, but also deteriorates with age. Therefore, the learning model 141 may further be a model that learned the relationship between temperature, age (number of days since manufacture or start of use (which may be years and months)), and phase error. In this case, the radio base station 200 transmits information indicating the manufacturing date or number of days since manufacture (which may be years and months) of each antenna, along with temperature information, to the information processing device 100. The information processing device 100 reads the learning model 141 corresponding to the received antenna information from the storage unit 140, and estimates the phase error of the antenna by inputting the received number of days since manufacture and temperature information to the read learning model 141. The information processing device 100 then transmits information indicating the estimated phase error associated with the information of each antenna to the radio base station 200. The phase correction unit 250 of the radio base station 200 applies the received phase error to the corresponding antenna. The wireless base station 200 communicates with the terminal 10 by performing beamforming using each antenna 220 after the phase error has been corrected.

[0054] (2) In the above embodiment, the learning model 141 is described as a model that has learned the relationship between the temperature of the antenna and the amount of phase error occurring at that temperature. However, this could also be a model that has learned the relationship between the difference between the measured temperature of the antenna and the reference temperature and the amount of phase error occurring at that temperature. That is, the explanatory variable could be the measured temperature of the antenna itself, or it could be the difference from the reference temperature.

[0055] (3) In the above embodiment, some of the functions of the information processing device 100 may be implemented by other devices. For example, the adjustment unit 134 of the information processing device 100 may be a function of the control unit of the wireless base station 200.

[0056] (4) The program for the information processing device 100 of the present disclosure to estimate the phase error based on the temperature information of the antenna may be provided stored in a computer-readable storage medium. The storage medium is a “non-temporary tangible medium” capable of storing the program. The storage medium may include any suitable storage medium such as an HDD or SSD, or two or more suitable combinations thereof. The storage medium may be volatile, non-volatile, or a combination of volatile and non-volatile. However, the storage medium is not limited to these examples and may be any device or medium capable of storing the program.

[0057] The information processing device 100 can realize the functions of the multiple functional units shown in each embodiment by, for example, reading a program stored on a storage medium and executing the read program. Furthermore, the program may be provided to the information processing device 100 via any transmission medium (such as a communication network or broadcast waves). The information processing device 100 can realize the functions of the multiple functional units shown in each embodiment by, for example, executing a program downloaded via the Internet or the like. This program may be executed by the information processing device 100 or the like.

[0058] The program can be implemented using, but is not limited to, scripting languages ​​such as ActionScript and JavaScript®, object-oriented programming languages ​​such as Objective-C, Java®, and Python®, and markup languages ​​such as HTML5.

[0059] At least a portion of the processing in the information processing device 100 may be implemented by cloud computing, which is comprised of one or more computers. Furthermore, each functional unit of the information processing device 100 may be implemented by one or more circuits that implement the functions shown in the above embodiment, or the functions of multiple functional units may be implemented by one circuit.

[0060] (5) The various methods and processes shown in the above embodiments and modifications may be combined or modified as appropriate, within the scope that the information processing device 100 can use to estimate the nonlinear phase error caused by the temperature dependence of the antenna.

[0061] (6) According to each aspect of the present disclosure described above, it is possible to accurately estimate the amount of phase error in accordance with the temperature change of the antenna, and to accurately perform beamforming in communication with terminals of wireless base stations, thereby providing a comfortable communication environment and contributing to the achievement of Sustainable Development Goal (SDG) 9, "Build resilient infrastructure, promote inclusive and sustainable industrialization and foster innovation."

[0062] 100 Information processing device 110 Communication unit 120 Input unit 130 Control unit 131 Acquisition unit 132 Estimation unit 133 Output unit 134 Adjustment unit 140 Storage unit 150 Output unit

[0063] 200 (200a, 200b) Wireless base station

[0064] 220 (220a-223a, 220b-223b) Antenna

[0065] 230 (230a-233a, 230b-233b) Temperature Sensor

[0066] 240 (240a~243a, 240b~243b) Phase Shifter

[0067] 250 (250a, 250b) Phase Correction Part

Claims

1. An information processing device comprising: an acquisition unit that acquires temperature data from temperature sensors provided on each of several antennas; an estimation unit that takes the temperature data acquired by the acquisition unit as input to a learning model prepared for each antenna, which has been learned using temperature data as an explanatory variable and the phase error that occurs in the communication of the antenna when the temperature indicated by the temperature data is the objective variable, and estimates the amount of phase error for each antenna; and an output unit that outputs the amount of phase error estimated by the estimation unit in association with each antenna.

2. The information processing apparatus according to claim 1, characterized in that the plurality of antennas are antennas that constitute a phased array antenna that performs beamforming to communicate with a terminal.

3. The information processing apparatus according to claim 1 or 2, wherein the plurality of antennas transmit a signal by beamforming with a phase corrected based on the phase error amount, the information processing apparatus comprises: a receiving unit that receives as a feedback signal the phase error between the phase of the signal actually received at the reference point and the phase of the received signal that should be received at the reference point, from a reference point that receives the signal; and an adjustment unit that adjusts the parameters of the learning model using the phase error indicated by the feedback signal, and the estimation unit estimates the phase error amount using the learning model adjusted by the adjustment unit.

4. A phase error estimation method comprising: an acquisition step in which a computer acquires temperature data from temperature sensors provided on each of several antennas; an estimation step in which a computer inputs the temperature data acquired in the acquisition step to a learning model prepared for each antenna, which has been learned with temperature data as an explanatory variable and the phase error that occurs in the communication of the antenna when the temperature indicated by the temperature data is the objective variable, in order to estimate the amount of phase error for each antenna; and an output step in which the amount of phase error estimated in the estimation step is output in association with each antenna.

5. A phase error estimation program that enables a computer to implement: an acquisition function that acquires temperature data from temperature sensors provided on each of several antennas; an estimation function that takes the temperature data acquired by the acquisition function as input to a learning model prepared for each antenna, which has been learned with temperature data as an explanatory variable and the phase error that occurs in the communication of the antenna when the temperature indicated by the temperature data is the objective variable, and estimates the amount of phase error for each antenna; and an output function that outputs the amount of phase error estimated by the estimation function, associated with each antenna.

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