Communication control method, terminal, communication control device, communication control system, and communication control program

Abstract

To emit radio waves from a mobile phone terminal with as much transmission power as possible within the range of standards.SOLUTION: A communication control method of the present invention is used for radio wave emission to evaluate radio wave interference from a terminal at an apparatus. The communication control method of the present invention executes a list creation step, a transmission power estimation step, and a terminal connection step. The list creation step creates a list of base stations that can be captured by the terminal. The transmission power estimation step estimates the transmission power of the terminal when connected to each of the base stations included in the list. The terminal connection step connects the terminal to a base station with the highest estimated transmission power.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a communication control method, a terminal, a communication control device, a communication control system, and a communication control program used for emitting radio waves to evaluate radio interference in equipment. [Background technology]

[0002] The guidelines for the use of mobile phones and other devices in medical institutions published by the Electromagnetic Compatibility Council (ECCC) set a guideline of 1 meter for the distance between medical equipment and mobile phones, and state that if each medical institution independently confirms the impact of radio waves on medical equipment, it may set a shorter distance (see Non-Patent Document 1). One method for independently confirming the impact is to use a mobile phone terminal connected to a base station or the like to emit mobile phone radio waves and confirm the impact on medical equipment, etc. (see Non-Patent Document 2). Research into creating a safe and secure mobile phone usage environment in medical institutions has also been reported (see Non-Patent Document 3). Patent Document 1 describes the invention of a terminal and radio wave emission method for conducting electromagnetic interference investigations using a mobile phone terminal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-175276 [Non-patent literature]

[0004] [Non-Patent Document 1] Electromagnetic Compatibility Council, "Guidelines for the Use of Mobile Phones, etc. in Medical Institutions," August 19, 2014, [Retrieved April 17, 2024], Internet<https: / / www.emcc-info.net / medical_emc / pubcom2 / 2608_1.pdf> . [Non-patent document 2] Shinya Nakamatsu, "Review of the rules for mobile phone use in hospitals based on the guidelines," presented at the "Symposium for Promoting Safe and Secure Radio Wave Use in Medical Institutions," sponsored by the Radio Environment Council of the Ministry of Internal Affairs and Communications, December 7, 2017, pp. 33-47, [Retrieved April 17, 2024], Internet<https: / / www.emcc-info.net / medical_emc / pdf / H291207symp-30.pdf> [Non-patent document 3] Ministry of Internal Affairs and Communications, "Survey on the Creation of a Safe and Secure Mobile Phone Usage Environment in Medical Institutions" Report, March 2017, retrieved April 17, 2024, Internet<https: / / www.tele.soumu.go.jp / resource / j / ele / medical / report.pdf> . Summary of the Invention [Problem to be solved by the invention]

[0005] Patent Document 1 describes a terminal and a radio wave emission method for conducting an electromagnetic interference investigation using a mobile phone terminal, but makes no mention of controlling the transmission power during this process. Generally, the possibility of electromagnetic interference occurring increases as the transmission power increases, so in electromagnetic interference evaluation, it is desirable to maximize the power emitted from the mobile phone terminal within the specified range.

[0006] The base station to which a typical mobile phone terminal connects is selected from among base stations that the terminal can capture based on preset criteria such as radio wave quality. The transmission power of the mobile phone terminal connected to the selected base station is determined by a control signal from the base station, but typical mobile phone terminals are controlled to minimize transmission power as much as possible while still maintaining communication quality. Therefore, typical mobile phone terminals do not have a function for selecting a base station to connect to through on-screen user operation. While some special maintenance terminals have a function for manually selecting a base station to connect to, they do not have the function to search for a base station to connect to with the aim of maximizing transmission power, or to select and connect to a base station with the highest transmission power.

[0007] On the other hand, when electromagnetic interference evaluation is performed using a mobile phone terminal connected to a base station, it is necessary to maximize the transmission power of the radio waves emitted from the terminal in order to obtain more conservative electromagnetic interference evaluation results. The key to achieving this is to maximize transmission power simply by selecting the base station to connect to, since the communication procedures between the base station and terminal, which follow a predetermined standard, cannot be changed. Even now, it is not impossible to select and connect to a specific base station by using some of the special maintenance terminals mentioned above, but it is not possible to estimate which base station to connect to in order to maximize the transmission power of the radio waves emitted from the terminal.

[0008] As an example, a simple method for estimating transmission power is to use the received power when a signal from each base station mounted on a terminal is received by a receiving antenna. (1) Fluctuations in received power and terminal transmission power over time due to changes in the surrounding environment, etc. (2) Differences in propagation paths between transmission and reception, and in the case of frequency duplex (FDD) bands, differences in propagation due to differences in upper and lower frequencies (3) Because the transmission power of the base station is unknown from the received power, selecting the base station with the lowest received power does not necessarily mean that the transmission power from the terminal will be the highest. (4) The sensitivity of the receiver (the device that receives and processes the signal emitted from the terminal) of the base station equipment varies from base station to base station, which also affects the control of the transmission power from the mobile phone terminal. Due to factors such as the above, simply selecting a base station based on the received power does not necessarily make it possible to maximize the transmission power of radio waves emitted from a terminal.

[0009] Furthermore, in normal operation of a mobile phone terminal, it is expected that the power consumption used for communication will be reduced in order to extend the terminal's battery life. Therefore, in communication procedures between a base station and a terminal that comply with a predetermined standard, it is expected that transmission power will be kept as low as possible. In such a situation, the object of the present invention is to provide a technology that enables a mobile phone terminal to emit radio waves with as much transmission power as possible within the range that complies with the standard. [Means for solving the problem]

[0010] The communication control method of the present invention is used for radio wave emission to evaluate radio wave interference from a terminal in equipment. The communication control method of the present invention executes a list creation step, a transmission power estimation step, and a terminal connection step. The list creation step creates a list of base stations that can be captured by the terminal. The transmission power estimation step estimates the transmission power of the terminal when connected to each of the base stations included in the list. The terminal connection step connects the terminal to the base station with the highest estimated transmission power. [Effects of the Invention]

[0011] According to the communication control method of the present invention, transmission power can be maximized within the range that complies with the standard, simply by devising the processing on the terminal side regarding the selection of the base station to connect to. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 2 is a diagram illustrating an example of the functional configuration of a terminal according to the first embodiment. [Figure 2] FIG. 3 is a diagram showing a processing flow of a communication control method according to the present invention. [Figure 3] FIG. 2 is a diagram showing an image of an electromagnetic interference evaluation in Example 1. [Figure 4] FIG. 10 is a diagram showing an example of a processing flow of a transmission power estimation step using received power. [Figure 5] FIG. 10 is a diagram showing an example of a processing flow of a transmission power estimation step using location information. [Figure 6]FIG. 10 is a diagram showing an example of a processing flow of a transmission power estimation step using transmission power at the time of packet transmission. [Figure 7] FIG. 10 is a diagram showing an example of the functional configuration of a terminal according to a first modified example. [Figure 8] FIG. 10 is a diagram showing an image of an electromagnetic interference evaluation according to the first modification. [Figure 9] FIG. 2 is a diagram showing an example of the functional configuration of a computer. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, embodiments of the present invention will be described in detail. Components having the same functions are given the same numbers, and duplicated explanations will be omitted. [Example]

[0014] FIG. 1 shows an example of the functional configuration of a terminal according to a first embodiment. FIG. 2 shows a processing flow of a communication control method of the present invention. FIG. 3 is a diagram illustrating an example of an electromagnetic interference evaluation according to the first embodiment. The terminal 200 is used to emit radio waves for evaluating radio interference in a device 900. The terminal 200 includes a reception unit 210, a radio wave reception unit 220, a list creation unit 230, a transmission power estimation unit 240, a connection control unit 250, and a radio wave emission unit 260. The terminal 200 may further include a location information acquisition unit 270 and a base station information acquisition unit 280. The terminal 200 and the base station 100 perform wireless communication based on standards such as local 5G, cellular 5G, or LTE. However, the wireless communication is not limited to these standards. 5G stands for 5th Generation, and LTE stands for Long Term Evolution. The device 900 is a device to be evaluated for radio interference, such as a medical device such as an electrocardiograph, a cardiac pacemaker, or an infusion pump. However, the device 900 does not need to be limited to a medical device, and may include machine tools and the like as long as it is a device that is subject to radio interference evaluation. Although three base stations 100-1, 2, and 3 are shown in Fig. 3, the number is not limited to three, and any number of base stations may be present.

[0015] The reception unit 210 receives user input regarding conditions for the electromagnetic interference evaluation, such as frequency (S210: reception step). The "frequency, etc." refers to the frequency band number F band Alternatively, the absolute value of the frequency [Hz] or EARFCN may be used. If the frequency to be investigated is not specified, it does not have to be specified. If not specified, the subsequent processing can be performed on all frequency bands. The radio wave receiving unit 220 receives radio waves from the surrounding base stations 100.

[0016] The list creation unit 230 creates a list L of base stations 100 that can be captured by the terminal 200. BS (S230: list creation step). BS Methods for creating the list include a method in which the radio wave receiving unit 220 records base stations from which radio waves can be received, a method in which information on base stations to which the terminal 200 has previously connected is used, and a method in which the user individually inputs base station information. Furthermore, if there is a database 300 that records base station information, such as the installation locations of base stations and the services provided, the terminal 200 may also include a location information acquiring unit 270 and a base station information acquiring unit 280. The location information acquiring unit 270 acquires the location information of the terminal 200. Then, the base station information acquiring unit 280 acquires the base station information from the database 300. The list creating unit 230 creates a list L of base stations 100 that can be captured from the location information and base station information of the terminal. BS Just create the following.

[0017] The database 300 may be provided inside the terminal 200 or may be external to the terminal 200. The base station information acquisition unit 280 may be provided with an information acquisition means according to the environment in which the database 300 exists. The "base station information" may include, for example, the location of the base station, information on the services provided, and the received power P rx and transmission power P tx a constant indicating the correlation (constants a and b described later) or a correspondence table indicating the past correlation, the distance to the terminal and the transmission power P txIt may also include information related to the estimation of the terminal's transmission power, such as constants (constants p and q described later) indicating the relevance to the terminal or a correspondence table indicating past relevance.

[0018] The transmission power estimation unit 240 estimates the transmission power of the terminal 200 when connected to each of the base stations 100 included in the list (S240: transmission power estimation step). "Estimating" includes not only determining the transmission power as a numerical value, but also determining that the transmission power is not large enough to evaluate radio interference, even if a specific numerical value is not determined. The present invention is intended for use in radio wave emissions from a terminal in equipment to evaluate radio interference. Therefore, if it is determined that the transmission power cannot be used to evaluate radio interference, there is no need to determine a numerical value. Furthermore, when determining the transmission power as a numerical value, "estimating" includes estimating it through calculation, measuring the actual transmission power, and obtaining a measured value.

[0019] FIG. 4 shows an example of a process flow for the transmission power estimation step using received power, FIG. 5 shows an example of a process flow for the transmission power estimation step using location information, and FIG. 6 shows an example of a process flow for the transmission power estimation step using the transmission power at the time of packet transmission. Any of the process flows may be applied to the transmission power estimation step S240. In these figures, when determining whether transmission power has been estimated for all base stations, the process may be judged to have been "estimated" for a base station whose transmission power is not sufficient for evaluating radio interference, for example, because the received power from the base station is greater than a threshold or the distance between the base station and the terminal is shorter than a threshold. For example, the process may be performed to determine the transmission power values ​​for all base stations, or the process may be performed to determine the transmission power values ​​for a portion of base stations necessary to find the base station that terminal 200 uses to output the maximum transmission power (the process may not be performed for base stations that do not require the process to determine the transmission power values).

[0020] First, the processing flow will be described with reference to Fig. 4. If there are base stations for which estimation has not yet been performed (if step S241 is No), the transmission power estimation unit 240 selects one base station from among the base stations for which estimation has not yet been performed (S241). The radio wave receiving unit 220 measures the received power from the selected base station (S220). The transmission power estimation unit 240 estimates the transmission power from the terminal 200 when connected to the selected base station (S245). The received power P rx From the value of the transmission power P tx As a method of estimating the received power P rx and transmission power P tx Alternatively, a correspondence table recording the past correlation between the received and transmitted levels may be used. For example, Non-Patent Document 3 shows the relationship between the received and transmitted levels at a mobile phone terminal, and it is estimated that if this relationship is expressed as a function, the formula will differ depending on the communication conditions. Therefore, there is a certain degree of rationality in determining values ​​using an estimation algorithm or a correspondence table, rather than simply using a conversion formula using a linear relationship. As the simplest example, a conversion formula using a linear function is used to determine the transmitted power P tx If a single formula is used to estimate the P tx = a × P rx +b Here, a and b are constants determined by past data or experiments, and different values ​​may be used depending on the type of base station, etc. Information on the type of base station may be acquired by the base station information acquisition unit 280. Note that, as a method other than the conversion formula and the correspondence table, the received power P rx and transmission power P tx Alternatively, estimation may be performed using an estimation algorithm that uses machine learning or the like, which uses past associations as learning data. If step S241 is Yes, step S240 ends (the process proceeds to the next step S251).

[0021] Next, the processing flow will be explained with reference to Fig. 5. The base station information acquisition unit 280 acquires base station information including the location information of the base station from the database 300 (S280). The location information acquisition unit 270 acquires the location information of the terminal 200 (S270). Note that if the base station information and the location information of the terminal 200 have been acquired in the list creation step S230, S280 and S270 may be omitted in the transmission power estimation step S240. If there are base stations for which estimation has not yet been performed (if step S241 is No), the transmission power estimation unit 240 selects one base station from among the base stations for which estimation has not yet been performed (S241). The transmission power estimation unit 240 estimates the transmission power from the terminal 200 when connected to the selected base station (S246). Transmission power P tx As a method of estimating, there are conversion formulas using linear functions, quadratic functions, exponential functions, logarithmic functions, etc., and the relationship between location information and transmission power P tx In the simplest example, a conversion formula using an exponential function with a negative order may be used to calculate the transmission power P tx When a single formula is used to estimate P tx =p÷dist 2 +q Here, dist is the distance between the terminal and the base station, and p and q are constants determined by past data or experiments. In addition to the conversion formula and the correspondence table, there is also a method for calculating the transmission power P tx Alternatively, estimation may be performed using an estimation algorithm that uses machine learning or the like, which uses past associations as learning data. If step S241 is Yes, step S240 ends (the process proceeds to the next step S251).

[0022] Finally, the processing flow will be explained with reference to Fig. 6. If there are base stations for which estimation has not yet been performed (if step S241 is No), the transmission power estimation unit 240 selects one base station from among the base stations for which estimation has not yet been performed (S241). The connection control unit 250 connects the terminal 200 to the selected base station 100 (S252). The terminal 200 transmits a predetermined short packet from the terminal 200 to the base station 100 (S253). The transmission power estimation unit 240 acquires the transmission power at the time of transmission and sets it as the estimated transmission power (S247). Note that if step S241 is Yes, step S240 ends (progresses to the next process S251).

[0023] The connection control unit 250 connects the terminal 200 to the base station 100 with the highest estimated transmission power (S251: terminal connection step). The radio wave emitting unit 260 emits radio waves (S260: radio wave emitting step). According to the communication control method of the present invention, it is possible to maximize transmission power within the range complying with the standard simply by devising processing on the terminal side related to the selection of the base station to connect to. Therefore, it is possible to provide a terminal that can be used to emit radio waves for evaluating radio interference without changing the processing function on the base station side. [Variation 1]

[0024] FIG. 7 shows an example of the functional configuration of a terminal according to Modification 1. FIG. 8 is a diagram illustrating an example of an electromagnetic interference evaluation according to Modification 1. The processing flow of the communication control method is the same as that shown in FIG. 2. A communication control system 203 includes a terminal 201 and a communication control device 202 that can communicate with each other. In the first embodiment, the terminal 200 includes the reception unit 210, the radio wave reception unit 220, the list creation unit 230, the transmission power estimation unit 240, the connection control unit 250, the radio wave transmission unit 260, the location information acquisition unit 270, and the base station information acquisition unit 280. However, only the radio wave reception unit 220, the radio wave transmission unit 260, and the location information acquisition unit 270 need to be present inside the terminal itself. The reception unit 210, the list creation unit 230, the transmission power estimation unit 240, the connection control unit 250, and the base station information acquisition unit 280 may be located in the terminal 201 or the communication control device 202. The functions and processing flow of each component are the same as those of the first embodiment. Therefore, the same effects as those of the first embodiment can be obtained.

[0025] <Hardware configuration> The block diagrams used to explain the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using a single device that is physically or logically coupled, or may be realized using two or more physically or logically separated devices that are directly or indirectly connected (for example, using wires, wirelessly, etc.) and these multiple devices. The functional block may also be realized by combining the single device or multiple devices with software.

[0026] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocation, mapping, and assignment. For example, a functional block (component) that performs transmission is called a transmitting unit or transmitter. As mentioned above, there are no particular limitations on how these functions are implemented.

[0027] For example, a base station, a user terminal, etc. according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 9 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment of the present disclosure. The above-described base station 100, terminals 200 and 201, and communication control device 202 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0028] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configurations of the base station 100, the terminals 200 and 201, and the communication control device 202 may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.

[0029] Each function in the base station 100, terminals 200, 201, and communication control device 202 is realized by loading specified software (programs) onto hardware such as a processor 1001 and memory 1002, causing the processor 1001 to perform calculations, control communication by the communication device 1004, and control at least one of reading and writing data in the memory 1002 and storage 1003.

[0030] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, etc.

[0031] Furthermore, the processor 1001 reads programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes in accordance with these. The programs used are those that cause a computer to execute at least some of the operations described in the above-described embodiments. For example, the terminal 200 may be implemented by a control program stored in the memory 1002 and running on the processor 1001, and similar implementations may also be made for other functional blocks. While the above-described various processes have been described as being executed by one processor 1001, they may also be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may also be transmitted from a network via a telecommunications line.

[0032] The memory 1002 is a computer-readable recording medium and may be configured, for example, by at least one of a read-only memory (ROM), an erasable programmable ROM (EPROM), an electrically erasable programmable ROM (EEPROM), a random access memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to an embodiment of the present disclosure.

[0033] Storage 1003 is a computer-readable recording medium, and may be composed of at least one of, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray disc), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy disk, a magnetic strip, etc. Storage 1003 may also be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other appropriate medium including at least one of memory 1002 and storage 1003.

[0034] The communication device 1004 is hardware (transmission / reception device) for communicating between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., to realize at least one of, for example, Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0035] The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that receives input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one device (for example, a touch panel).

[0036] Furthermore, each device, such as the processor 1001 and the memory 1002, is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0037] Furthermore, the base station 100, the terminals 200 and 201, and the communication control device 202 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0038] <Processing Procedure> The order of the procedures, sequences, flowcharts, etc. of each aspect / embodiment described in this disclosure may be changed unless it is consistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented. [Explanation of symbols]

[0039] 100 Base station 200, 201 Terminal 202 Communication control device 203 Communication control system 210 Reception unit 220 Radio wave receiving unit 230 List creation unit 240 Transmission power estimation unit 250 connection control unit 260 radio wave emission unit 270 Location information acquisition unit 280 Base station information acquisition unit 300 databases 900 devices

Claims

1. A communication control method used for radio wave emission to evaluate radio wave interference from a terminal in a device, comprising: a list creation step of creating a list of base stations that can be captured by the terminal; a transmission power estimation step of estimating a transmission power of the terminal when connected to each of the base stations included in the list; a terminal connecting step of connecting the terminal to the base station with the maximum estimated transmission power; A communication control method for performing the above.

2. 2. The communication control method according to claim 1, In the transmission power estimation step, the transmission power of the terminal is estimated from the reception power of the terminal by estimation using a predetermined conversion formula or a predetermined correspondence table. A communication control method comprising:

3. 2. The communication control method according to claim 1, The terminal can acquire base station information including location information of the base station; In the transmission power estimation step, the transmission power of the terminal is estimated from the location information of the terminal and the base station information by estimation using a predetermined conversion formula or a predetermined correspondence table. A communication control method comprising:

4. 2. The communication control method according to claim 1, The terminal can acquire base station information including location information of the base station; In the list creation step, a list of base stations that can be captured is created from the location information of the terminal and the base station information. A communication control method comprising:

5. 2. The communication control method according to claim 1, In the transmission power estimation step, the terminal connects to each of the base stations included in the list, and acquires the transmission power when transmitting a predetermined packet, thereby estimating the transmission power of the terminal when connected to each of the base stations. A communication control method comprising:

6. A terminal used to emit radio waves to evaluate radio interference in equipment, a list creation unit that creates a list of base stations that can be captured by the terminal; a transmission power estimation unit that estimates transmission power of the terminal when connected to each of the base stations included in the list; A connection control unit that connects the terminal to the base station with the highest estimated transmission power. A terminal comprising:

7. A communication control device used for radio wave emission to evaluate radio wave interference from a terminal in a device, a list creation unit that creates a list of base stations that can be captured by the terminal; a transmission power estimation unit that estimates transmission power of the terminal when connected to each of the base stations included in the list; a connection control unit that connects the terminal to the base station that maximizes the estimated transmission power; A communication control device comprising:

8. A communication control system comprising a terminal used for emitting radio waves to evaluate radio interference in equipment and a communication control device, a list creation unit that creates a list of base stations that can be captured by the terminal; a transmission power estimation unit that estimates transmission power of the terminal when connected to each of the base stations included in the list; a connection control unit that connects the terminal to the base station that maximizes the estimated transmission power; A communication control system comprising:

9. A communication control program that causes a computer to execute the communication control method according to any one of claims 1 to 5.

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