JP2017169003A - Measurement device and measuring method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently evaluate the communication quality of a wireless LAN in a wide range.SOLUTION: When a measurement device 200 acquires a frame which is transmitted from an identical access point and terminal in an identical time zone from a plurality of capture devices 100X and 100Y which are disposed at different points, the measurement device 200 selects a frame at the satisfactorily received side in the plurality of capture devices 100, and analyzes the communication quality in the wireless LAN.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a measuring apparatus and the like.

  In a wireless local area network (LAN), communication quality troubles such as slow communication and easy disconnection may occur. There are many causes for this wireless LAN trouble. For example, the cause of the trouble includes a design error of the wireless LAN system, the magnitude of traffic inside and outside the business, radio wave intensity, noise, equipment failure, and factors other than the wireless LAN.

  There are a wide variety of methods for evaluating wireless LAN communication quality troubles. For example, in order to investigate whether there is a design error, the design and settings are reviewed. In order to evaluate the size of business traffic, the amount of traffic is examined using a LAN monitoring device. In order to examine non-business traffic, the corresponding access point is investigated. In order to evaluate the radio field intensity, the distribution of the radio field intensity at points on the floor is investigated. To evaluate noise, a spectrum analyzer is used. To evaluate equipment failure, investigate equipment maintenance manuals.

  For example, when evaluating the above-mentioned wireless LAN communication quality trouble, a measurement device that captures wireless LAN frames is placed at one point, and the wireless LAN frames in operation are captured and stored, and later captured. A method of analyzing the data can be considered.

JP 2008-109570 A JP 2007-124215 A JP 2008-109571 A

  However, the above-described conventional technique has a problem that the communication quality of the wireless LAN cannot be efficiently evaluated over a wide range.

  For example, in the above-described conventional technology, since the measuring device is only arranged at one point, the communication quality of the wireless LAN can be evaluated only locally. In addition, if a plurality of measuring devices are simply arranged at a plurality of points and the communication quality of the wireless LAN is evaluated, a large number of frames to be analyzed are generated, and it is difficult to say that the communication quality can be evaluated efficiently.

  Furthermore, it is conceivable to move the measurement device on a carriage and capture frames at multiple points. However, since the capture data that can be acquired at each point is short-term, the wireless LAN that is in operation can be used for a long time. Can no longer be evaluated.

  In one aspect, an object of the present invention is to provide a measuring apparatus and a measuring method capable of efficiently evaluating communication quality of a wireless LAN over a wide range.

  In the first plan, the measurement apparatus includes an acquisition unit, a selection unit, and an analysis unit. The acquisition unit acquires frames from a plurality of capture devices that acquire frames transmitted and received by wireless communication between the access point and the terminal device at a plurality of different points. In the plurality of frames acquired by the acquisition unit, when there are a plurality of frames transmitted from the same access point in the same time zone, the selection unit selects a frame that is determined to be the best received by the capture device. If there are a plurality of frames transmitted from the same terminal in the same time zone, the frame that is determined to be the best received by the capture device is selected. The analysis unit analyzes the communication quality based on the frame selected by the selection unit.

  Wireless LAN communication quality can be efficiently evaluated over a wide range.

FIG. 1 is a diagram illustrating a configuration of a system according to the present embodiment. FIG. 2 is a diagram illustrating an example of a data structure of a frame. FIG. 3 is a functional block diagram showing the configuration of the capture device. FIG. 4 is a diagram illustrating an example of the data structure of the frame storage table. FIG. 5 is a diagram illustrating an example of the data structure of the AP list. FIG. 6 is a diagram illustrating an example of the data structure of the terminal list. FIG. 7A is a diagram illustrating an example of a data structure of statistical information of the capture device 100X. FIG. 7B is a diagram illustrating an example of a data structure of statistical information of the capture device 100Y. FIG. 8 is a functional block diagram showing the configuration of the measuring apparatus. FIG. 9 is a diagram illustrating an example of the data structure of the capture table. FIG. 10 is a diagram illustrating an example of the data structure of the AP list of the measurement apparatus. FIG. 11 is a diagram illustrating an example of the data structure of the terminal list of the measurement apparatus. FIG. 12 is a diagram illustrating an example of a data structure of the AP characteristic synthesis table. FIG. 13 is a diagram illustrating an example of a data structure of the terminal frame table. FIG. 14 is a diagram (1) illustrating an example of the data structure of the downlink frame table. FIG. 15 is a diagram (2) illustrating an example of the data structure of the downlink frame table. FIG. 16 is a diagram illustrating an example of the data structure of the uplink frame table. FIG. 17 is a diagram illustrating an example of a data structure of communication quality information. FIG. 18 is a diagram for explaining processing in which the preprocessing unit generates an AP list. FIG. 19 is a diagram for explaining processing of generating a terminal list by the preprocessing unit. FIG. 20 is a flowchart illustrating the processing procedure of the capture apparatus according to the present embodiment. FIG. 21 is a flowchart illustrating the processing procedure of the measurement apparatus according to the present embodiment.

  Embodiments of a measuring apparatus and a measuring method disclosed in the present application will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments.

  FIG. 1 is a diagram illustrating a configuration of a system according to the present embodiment. As shown in FIG. 1, in this system, APs (Access Points) 1, 2, 3, terminals α, β, γ, and capture devices 100X, 100Y are arranged on a floor 5. AP 4 is arranged outside the floor 5. The capture devices 100X and 100Y output information to the measurement device 200 when connected to the measurement device 200. The measuring device 200 may be installed on the floor 5 or may be arranged outside the floor 5.

  Terminals α, β, and γ are connected to an AP within a communication range by a wireless LAN (Local Area Network). For example, the terminal α is connected to the APs 1, 2, 3, and 4. This system may include terminals other than the terminals α, β, and γ. Moreover, this system may include APs other than AP1-4.

  The terminal α is a device that transmits and receives frames to and from other terminals via the AP. For example, the terminal α is connected to any one of the APs 1, 2, 3, and 4 through the wireless LAN, and transmits a frame to another terminal. The description regarding the terminals β and γ is the same as the description corresponding to the terminal α.

  Here, an example of a frame transmitted and received by the terminal α will be described. FIG. 2 is a diagram illustrating an example of a data structure of a frame. As shown in FIG. 2, this frame has a PHY (Physical) header, address information, sequence control information, and data. Among these, the PHY header is a header having information on a physical connection format, and has information such as a conversion method, a bit rate, and reception timing. The address information includes a MAC (Media Access Control) address of a terminal serving as a frame destination, a MAC address of a terminal serving as a frame transmission source, a MAC address of a relayed AP, and the like. The sequence control information is a serial number assigned to each frame. The data corresponds to user data.

  On the wireless LAN, three types of frames, data frames, management frames, and control frames, flow. Data frames are frames that carry end-user data packets. The management frame is a frame for managing the connection between the terminal and the AP. The control frame is a frame for data packet flow control and delivery confirmation.

  For example, the transmission source device (terminal or AP) waits for a response (ACK) from the transmission destination device after transmitting the data frame to the transmission destination device (terminal or AP). When the destination device receives the data frame, it sends a response to the source device.

  Upon receiving the response, the source device transmits the next data frame with a higher bit rate modulation scheme. On the other hand, when the transmission source device does not receive a response, the transmission source device retries (retransmits) the next data frame with a modulation method with a lower bit rate. When retrying a data frame, the transmission source device stores information indicating that the data frame is a retransmission frame in the data frame.

  Basically, if the bit rate is high, the data transfer speed becomes high, but the modulation method becomes weak against noise, and retry is likely to occur. When the retry rate is large, the time until the frame transmitted by the transmission source device is received by the transmission destination device increases. As a result, end-to-end data transfer throughput decreases.

  In this embodiment, the data frame, the management frame, and the control frame are collectively referred to as a frame unless otherwise distinguished.

  Returning to the description of FIG. The APs 1, 2, 3, and 4 are devices that perform data communication by connecting to terminals α, β, and γ through a wireless LAN. In the example shown in FIG. 1, AP1 is connected to the terminal α by a wireless LAN. For example, the terminal α transmits a frame to another terminal via AP1.

  The capture devices 100X and 100Y are devices that capture frames transmitted and received between the terminals α, β, and γ and the APs 1 to 4. For example, a range in which the capture device 100X can capture a frame is a range 1x. A range in which the capture device 100Y can capture a frame is a range 1y. For example, the ranges 1x and 1y are ranges corresponding to a circle having a radius of 20 m with the capture devices 100X and 100Y as the center.

  The capture devices 100X and 100Y start operating simultaneously and capture frames at the same time interval. In the following description, a frame captured by the capture devices 100X and 100Y is appropriately expressed as capture data. It is assumed that the time of the capture device 100X and the time of the capture device 100Y are set in advance at the same time.

  The capture devices 100X and 100Y execute processing as described later based on the capture data to generate analysis data. When the capture devices 100X and 100Y are connected to the measurement device 200, the capture devices 100X and 100Y notify the measurement device 200 of analysis data and capture data. For example, the worker operates the capture devices 100X and 100Y for a certain period of time, and then connects the capture devices 100X and 100Y and the measurement device 200 via a wired LAN or a wireless LAN.

  The measurement device 200 is a device that acquires analysis data and capture data from the capture devices 100X and 100Y, and generates information related to wireless LAN communication quality based on the acquired analysis data and capture data.

  Next, an example of the configuration of the capture device 100X illustrated in FIG. 1 will be described. Since the configuration of the capture device 100Y is the same as that of the capture device 100Y, description thereof is omitted. FIG. 3 is a functional block diagram showing the configuration of the capture device. As illustrated in FIG. 3, the capture device 100X includes a frame acquisition unit 110, an input unit 120, a storage unit 130, and a control unit 140.

  The frame acquisition unit 110 is a processing unit that acquires (captures) all frames transmitted and received through wireless LAN communication between the APs 1 to 4 and the terminals α, β, and γ. The frame acquisition unit 110 outputs the acquired frame to the registration unit 141.

  The input unit 120 is an input device that inputs various data to the control unit 140. For example, the input unit 120 corresponds to an input button, a touch panel, or the like.

  The storage unit 130 includes a frame storage table 131, an AP list 132, a terminal list 133, radio wave occupation rate information 134, and statistical information 135. The storage unit 130 corresponds to, for example, a semiconductor memory device such as a RAM (Random Access Memory), a ROM (Read Only Memory), and a flash memory (Flash Memory), and a storage device such as an HDD (Hard Disk Drive).

  The frame storage table 131 is a table for storing frames acquired by the frame acquisition unit 110. FIG. 4 is a diagram illustrating an example of the data structure of the frame storage table. As shown in FIG. 4, the frame storage table 131 has a plurality of storage areas 30a, 30b, and 30c. In the example illustrated in FIG. 4, the storage areas 30 a to 30 c are illustrated, but the frame storage table 131 includes other storage areas. In the following description, the storage areas 30a to 30c are collectively referred to as a storage area 30 as appropriate.

  Each storage area 30 stores frames acquired by the frame acquisition unit 110 at different measurement slot times. For example, the storage area 30a stores the frame acquired by the frame acquisition unit 110 at a certain measurement slot time. The storage area 30b stores the frame acquired by the frame acquisition unit 110 in the measurement slot time next to the measurement slot time for the storage area 30a. The storage area 30c stores the frame acquired by the frame acquisition unit 110 in the measurement slot time next to the measurement slot time for the storage area 30b.

  In each storage area 30, a frame is associated with attribute information of this frame. The frame attribute information includes, for example, information on the bit rate of the corresponding frame and information on whether or not the corresponding frame is a retry frame. Further, the signal strength information at the time of receiving the frame may be included as the frame attribute information. The frame attribute information may further include information regarding other attributes regarding the frame.

  The AP list 132 includes information on MAC addresses of business APs, MAC addresses of public WiFi (Wireless Fidelity Registered Trademarks), and MAC addresses of other APs. FIG. 5 is a diagram illustrating an example of the data structure of the AP list. As shown in FIG. 5, the AP list 132 associates the division information, the MAC address, the AP name, the SSID (Service Set Identifier), and the channel information.

  In FIG. 5, the classification information is information indicating whether the corresponding AP is a business AP, a public WiFi AP, or another AP. When the classification information is “business use”, it indicates that the corresponding AP is a business use AP. When the classification information is “public WiFi”, it indicates that the corresponding AP is a public WiFi AP. When the classification information is “other”, it indicates that the corresponding AP is another AP.

  The MAC address indicates the MAC address of the corresponding AP. The AP name corresponds to the name of the corresponding AP. The SSID is an identifier of an access point. The channel information indicates a channel used by the corresponding AP. In the example of FIG. 5, the AP with the MAC address “a1: a2: a3: a4: a5: a6” is “for business”, the AP name is “AP1”, the SSID is “yyyy”, and is used. It is indicated that the channel to be played is 1ch.

  The terminal list 133 includes information on MAC addresses of business terminals and MAC addresses of other terminals. FIG. 6 is a diagram illustrating an example of the data structure of the terminal list. As shown in FIG. 6, this terminal list 133 associates the division information, the MAC address, the SSID, and the channel information.

  In FIG. 6, the classification information is information indicating whether the corresponding terminal is a business terminal, a public WiFi terminal, or another terminal. The MAC address indicates the MAC address of the corresponding terminal device. The SSID corresponds to the SSID of the AP used by the terminal. The channel information indicates a channel used by the corresponding terminal. In the example of FIG. 6, the terminal having the MAC address “p1: p2: p3: p4: p5: p6” is “business”, the SSID is “yyyy”, and the terminal to be used is 6ch. It is.

  The radio wave occupancy rate information 134 is radio wave occupancy rate information calculated by a radio wave occupancy rate calculation unit 142 described later. The explanation regarding the radio wave occupation rate will be described later.

  The statistical information 135 is information indicating the number of frames transmitted from the AP and the signal strength of the AP for each measurement slot time. The statistical information 135 is generated by a statistical information generation unit 144 described later.

  FIG. 7A is a diagram illustrating an example of a data structure of statistical information of the capture device 100X. As shown in FIG. 7A, the statistical information 135 includes statistical information 135Xa, 135Xb, 135Xc, and 135Xd. The statistical information 135Xa is statistical information regarding the frame transmitted from the AP1. The statistical information 135Xb is statistical information regarding the frame transmitted from the AP2. The statistical information 135Xc is statistical information regarding the frame transmitted from the AP3. The statistical information 135Xd is statistical information regarding the frame transmitted from the AP 4.

  The statistical information 135Xa will be described. The statistical information 135Xa associates the measurement start time, the measurement end time, the total number of transmission frames, and the signal strength. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. The time interval from the measurement start time to the measurement end time corresponds to the measurement slot time. The total number of transmission frames indicates the number of all frames transmitted from the AP 1 between the corresponding measurement start time and the measurement end time. The signal strength is an average value of the signal strength transmitted from the AP 1 from the corresponding measurement start time to the measurement end time.

  The description regarding the statistical information 135Xb to 135Xd is different from the statistical information 135Xa in that the AP that transmits the frame is AP2 to AP4, but the other descriptions are the same.

  As a reference example, an example of statistical information by the capture device 100Y is also shown. FIG. 7B is a diagram illustrating an example of a data structure of statistical information of the capture device 100Y. As illustrated in FIG. 7B, the statistical information 135 includes statistical information 135Ya, 135Yb, 135Yc, and 135Yd.

  The control unit 140 includes a registration unit 141, a radio wave occupation rate calculation unit 142, a list creation unit 143, a statistical information generation unit 144, and a transmission unit 145. The control unit 140 corresponds to an integrated device such as an ASIC (Application Specific Integrated Circuit) or an FPGA (Field Programmable Gate Array). The control unit 150 corresponds to an electronic circuit such as a CPU (Central Processing Unit) or an MPU (Micro Processing Unit).

  The registration unit 141 is a processing unit that registers information on the frames captured by the frame acquisition unit 110 in the frame storage table 131. The registration unit 141 registers frame information in the frame storage table 131 while switching the storage area of the frame storage table 131 that is a registration destination for each measurement slot time. The engineer may set and change the measurement slot time as appropriate.

  Here, the frame acquisition unit 110 switches the reception channel at a sufficiently short time interval and acquires a frame flowing through the corresponding reception channel. For example, the frame acquisition unit 110 switches the reception channel at a time interval of 250 ms. Therefore, when the registration unit 141 registers frame information in the corresponding storage area 30 during a certain measurement slot time, the storage area 30 stores the frame information of each channel.

  The radio wave occupation rate calculation unit 142 is a processing unit that calculates the radio wave occupation rate. The radio wave occupancy rate information calculated by the radio wave occupancy rate calculation unit 142 is defined as radio wave occupancy rate information 134. The radio wave occupation rate calculating unit 142 stores the radio wave occupation rate information 134 in the storage unit 130. As will be described later, the radio wave occupation rate information is associated with the radio wave occupation rate for each measurement slot time.

  An example of processing in which the radio wave occupation rate calculation unit 142 calculates “radio wave occupation rate” will be described. For example, the radio wave occupation ratio is defined by the equation (1). In equation (1), T1 corresponds to the time during which a frame is transmitted on the channel. T2 corresponds to the time when no frame is flowing on the channel. For this reason, the time obtained by adding T1 and T2 corresponds to the measurement slot time.

  Radio wave occupancy = T1 / (T1 + T2) (1)

  For example, the radio wave occupancy rate calculation unit 142 monitors the frame acquisition status of the frame acquisition unit 110 for each measurement slot time, and includes a time T1 during which frames are transmitted on the channel and a time T2 during which frames are not transmitted. Is identified.

  The list creation unit 143 is a processing unit that creates the AP list 132 and the terminal list 133 based on the frame storage table 131. The list creation unit 143 stores the AP list 132 and the terminal list 133 in the storage unit 130.

  An example of processing in which the list creation unit 143 creates the AP list 132 will be described. In the AP list 132, information on the MAC address, AP name, and SSID corresponding to the classification information “for business use” and “public WiFi” is set in advance. The list creation unit 143 compares the AP address (MAC address) of the frame stored in the frame storage table 131 with the MAC addresses of “business” and “public WiFi” in the AP list 132, and the MAC addresses that do not match Are registered in the AP list 132 as the MAC address of the classification information “others”. Further, the list creation unit 143 registers the AP name, SSID, and channel information in the AP list 132 as appropriate.

  An example of processing in which the list creation unit 143 generates the terminal list 133 will be described. The list creation unit 143 extracts, from the frame of the frame storage table 131, a frame that includes the MAC address of the AP of the division information “business use” in the AP list 132 in the address information. The list creation unit 143 identifies the MAC address of the terminal included in the extracted frame as the MAC address of the terminal having the classification information “for business use”, and registers it in the terminal list 133. The list creation unit 143 registers the SSID and channel information in the terminal list 133 as appropriate.

  The list creation unit 143 extracts, from the frame of the frame storage table 131, a frame that includes the MAC address of the AP of the classification information “Public WiFi” in the AP list 132 in the address information. The list creation unit 143 identifies the MAC address of the terminal included in the extracted frame as the MAC address of the terminal of the classification information “Public WiFi”, and registers it in the terminal list 133.

  The list creation unit 143 identifies the MAC addresses of the terminals other than the above-described classification information “business” and “public WiFi” as the MAC addresses of the terminals of the classification information “others”, and registers them in the terminal list 133. Hereinafter, a “frame” refers to a data frame.

  The statistical information generation unit 144 is a processing unit that generates statistical information 135 based on the frame storage table 131. An example of a process in which the statistical information generation unit 144 generates the statistical information 135Xa will be described. The statistical information generation unit 144 refers to the address information of the frame included in the measurement slot time and extracts the frame transmitted from the AP1. The statistical information generation unit 144 registers the number of extracted frames as the total number of transmission frames. The statistical information generation unit 144 calculates the signal strength by averaging the signal strength corresponding to the extracted frame, and registers the calculated signal strength. The statistical information generation unit 144 repeatedly executes the above processing for each measurement slot time, thereby calculating the total number of transmission frames and the signal strength for each measurement slot time, and registers them in the statistical information 135Xa. As already described, each measurement slot time corresponds to the time width from each measurement start time to the measurement end time.

  The process of generating the statistical information 135Xb to 135Xd by the statistical information generation unit 144 is the same as the process of generating the statistical information 135Xa except that the frames transmitted from the AP2 to AP4 are extracted.

  The transmission unit 145 is a processing unit that transmits analysis data and capture data to the measurement apparatus 200. Here, the analysis data is information including the AP list 132, the terminal list 133, the radio wave occupation rate information 134, and the statistical information 135. The capture data is information corresponding to the frame storage table 131.

  Next, an example of the configuration of the measuring apparatus 200 will be described. FIG. 8 is a functional block diagram showing the configuration of the measuring apparatus. As shown in FIG. 8, the measuring apparatus 200 includes an interface unit 210, an input unit 220, a display unit 230, a storage unit 240, and a control unit 250.

  The interface unit 210 is a processing unit that performs data communication by connecting to the capture devices 100X and 200X and other capture devices by wire or wireless. The interface unit 210 outputs data received from the capture devices 100X and 200X and other capture devices to the acquisition unit 251. In the following description, the capture devices 100X and 200X and other capture devices are collectively referred to as the capture device 100 as appropriate.

  The input unit 220 is an input device that inputs various data to the control unit 250. For example, the input unit 220 corresponds to an input button, a touch panel, a keyboard, and the like.

  The display unit 230 is a display device that displays information output from the control unit 250. For example, the display unit 230 displays information related to wireless LAN communication quality.

  The storage unit 240 includes a capture table 241, an AP list 242, a terminal list 243, an AP specific combination table 244, a terminal frame table 245, a downlink frame table 246, an uplink frame table 247, and communication quality information 248. The storage unit 240 corresponds to, for example, a semiconductor memory device such as a RAM (Random Access Memory), a ROM (Read Only Memory), and a flash memory (Flash Memory), and a storage device such as an HDD (Hard Disk Drive).

  The capture table 241 is a table that stores information acquired from the capture device 100X. FIG. 9 is a diagram illustrating an example of the data structure of the capture table. As shown in FIG. 9, the capture table 241 associates identification information, analysis data, and capture data. The identification information is information that uniquely identifies the capture device. The analysis data is analysis data acquired from the capture device 100. The analysis data is information including the AP list 132, the terminal list 133, the radio wave occupation rate information 134, and the statistical information 135 as described above. The capture data is information corresponding to the frame storage table 131. The capture data is capture data acquired from the capture device 100. The capture data corresponds to the frame storage table 131 as described above.

  The AP list 242 is an AP list obtained by integrating AP lists received from the capture device 100. FIG. 10 is a diagram illustrating an example of the data structure of the AP list of the measurement apparatus. As illustrated in FIG. 10, the AP list 242 associates partition information, a MAC address, an AP name, an SSID, and channel information. The description regarding the classification information, the MAC address, the AP name, the SSID, and the channel information is the same as that described in the AP list 132.

  The terminal list 243 is a terminal list in which terminal lists received from the capture device 100 are integrated. FIG. 11 is a diagram illustrating an example of the data structure of the terminal list of the measurement apparatus. As illustrated in FIG. 11, the terminal list 243 associates division information, a MAC address, an SSID, and channel information. The description regarding the classification information, the MAC address, the SSID, and the channel information is the same as that described in the terminal list 133.

  The AP characteristic synthesis table 244 holds information for specifying the capture device 100 that has successfully received a frame transmitted from the AP. FIG. 12 is a diagram illustrating an example of a data structure of the AP characteristic synthesis table. As illustrated in FIG. 12, the AP characteristic synthesis table 244 includes determination tables 244a, 244b, 244c, and 244d. The determination table 244a is a table for specifying a capture device that has successfully received a frame transmitted from the AP1. The determination table 244b is a table for specifying a capture device that has successfully received a frame transmitted from the AP2. The determination table 244c is a table for specifying a capture device that has successfully received a frame transmitted from the AP3. The determination table 244d is a table for specifying a capture device that has successfully received a frame transmitted from the AP4.

  The determination table 244a will be described. The determination table 244a associates the selected capture device, the measurement start time, the measurement end time, the number of AP frame transmissions, and the AP signal strength. The selected capture device is information for identifying the capture device that has received the frame from the AP best during the corresponding measurement slot time (the time from the measurement start time to the measurement end time). The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended.

  The number of AP frame transmissions indicates the number of frames received by the capture apparatus 100 during the corresponding measurement slot time. In the example shown in FIG. 12, the number of frames received by the capture device 100X and the capture device 100Y is shown.

  The AP signal strength indicates the strength of a signal (frame) transmitted from the AP 1 by the capture device 100 during the corresponding measurement slot time. In the example illustrated in FIG. 12, the capture device 100X indicates the strength of a signal transmitted from AP1, and the capture device 100Y indicates the strength of a signal transmitted from AP1.

  The description regarding the determination tables 244b to 244d is different from the determination table 244a in that the AP that transmits the frame is AP2 to AP4, but the other descriptions are the same.

  The terminal frame table 245 is a table that holds information related to the communication quality of frames transmitted from the terminal to the capture device 100. FIG. 13 is a diagram illustrating an example of a data structure of the terminal frame table. In the example shown in FIG. 13, the terminal frame table 245 includes communication quality tables 245a and 245b. The communication quality table 245a is a table indicating the communication quality based on the frame captured by the capture device 100X and transmitted from the terminal α. The communication quality table 245b is a table indicating the communication quality based on the frame transmitted from the terminal α captured by the capture device 100Y. Here, the communication quality tables 245a and 245b based on the frames transmitted from the terminal α are shown, but the terminal frame table 245 may have a communication quality table based on the frames transmitted from the terminals β and γ. good.

  The communication quality table 245a will be described. The communication quality table 245a associates the measurement start time, the measurement end time, the total number of transmission frames, the number of transmission retries, the transmission average rate, the transmission maximum rate, and the signal output. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended.

  The total number of transmission frames indicates the number of frames transmitted by the terminal α in the corresponding measurement slot time (time from the measurement start time to the measurement end time). The number of transmission retries indicates the number of frame retries performed by the terminal α during the corresponding measurement slot time. The transmission average rate is an average value of bit rates used when the terminal α transmits a frame in the measurement slot time. The maximum transmission rate is the highest bit rate used when the terminal α transmits a frame in the corresponding measurement slot time. The signal output indicates a signal output when the terminal α transmits a frame.

  The description regarding the communication quality table 245b is different from the communication quality table 245a in that the device that captures the frame is the capture device 100Y, but the other descriptions are the same.

  The downlink frame table 246 is a table that holds information related to the communication quality of frames transmitted from the AP1 to AP4 to the terminal. 14 and 15 are diagrams illustrating an example of the data structure of the downlink frame table. As illustrated in FIGS. 14 and 15, the downstream frame table 246 includes tables 246Xa to 246Xd and 246Ya to 246Yd.

  Among these, the tables 246Xa to 246Xd are tables generated by analyzing frames transmitted from the AP1 to AP4 to the terminal α captured by the capture device 100X.

  The table 246Xa associates the measurement start time, the measurement end time, and AP1-4 → the number of terminal α frames. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. AP1 → terminal α frame number is the number of frames transmitted from AP1 to terminal α. AP2 → terminal α frame number is the number of frames transmitted from AP2 to terminal α. AP3 → terminal α frame number is the number of frames transmitted from AP3 to terminal α. AP4 → terminal α frame number is the number of frames transmitted from AP4 to terminal α.

  The table 246Xb associates the measurement start time, the measurement end time, and AP1-4 → the number of terminal α retry frames. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. AP1 → terminal α retry count is the number of frames retried when transmitting from AP1 to terminal α. AP2 → terminal α retry count is the number of frames retried when transmitting from AP2 to terminal α. AP3 → terminal α retry count is the number of frames retried when transmitting from AP3 to terminal α. AP4 → terminal α retry count is the number of frames retried when transmitting from AP1 to terminal α.

  The table 246Xc associates the measurement start time, the measurement end time, and AP1-4 → terminal α average bit rate. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. AP1 → terminal α average bit rate is an average bit rate when a frame is transmitted from AP1 to terminal α. AP2 → terminal α average bit rate is an average bit rate when a frame is transmitted from AP2 to terminal α. AP3 → terminal α average bit rate is an average bit rate when a frame is transmitted from AP3 to terminal α. AP4 → terminal α average bit rate is an average bit rate when a frame is transmitted from AP4 to terminal α.

  The table 246Xd associates the measurement start time, the measurement end time, and AP1-4 → terminal α maximum bit rate. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. AP1 → terminal α maximum bit rate is the maximum bit rate when a frame is transmitted from AP1 to terminal α. AP2 → terminal α maximum bit rate is the maximum bit rate when a frame is transmitted from AP2 to terminal α. AP3 → terminal α maximum bit rate is the maximum bit rate when a frame is transmitted from AP3 to terminal α. AP4 → terminal α maximum bit rate is the maximum bit rate when a frame is transmitted from AP4 to terminal α.

  The tables 246Ya to 246Yd are tables generated by analyzing frames transmitted from the AP1 to AP4 and captured by the capture device 100Y to the terminal α. The description regarding the tables 246Ya to 246Yd differs from the tables 246Xa to 246Xd in that the frame to be analyzed is captured by the capture device 100Y, but the other descriptions are the same.

  In the downlink frame table 246 shown in FIGS. 14 and 15, tables based on frames transmitted from the AP1 to AP4 to the terminal α are shown, but the present invention is not limited to this. The downlink frame table 246 may include a table based on frames transmitted from the AP1 to AP4 to the terminals β and γ.

  The uplink frame table 247 is a table that holds information related to the number of frames transmitted from the terminal to the APs 1 to 4. FIG. 16 is a diagram illustrating an example of the data structure of the uplink frame table. As shown in FIG. 16, the upstream frame table 247 includes tables 247Xa and 247Ya.

  The table 247Xa associates the measurement start time, the measurement end time, and the terminal α → the number of AP1 to 4 frames. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended. The terminal α → AP1 frame number is the number of frames transmitted from the terminal α to AP1. The terminal α → AP2 frame number is the number of frames transmitted from the terminal α to AP2. The terminal α → AP3 frame number is the number of frames transmitted from the terminal α to AP3. The terminal α → AP4 frame number is the number of frames transmitted from the terminal α to AP4.

  The description regarding the table 247Ya is different from the table 247Xa in that the frame to be analyzed is captured by the capture device 100Y, but the other description is the same.

  In the uplink frame table 247 illustrated in FIG. 16, a table based on frames transmitted from the terminal α to AP1 to AP4 is illustrated, but the present invention is not limited to this. The uplink frame table 247 may include a table based on frames transmitted from the terminals β and γ to AP1 to AP4.

  The communication quality information 248 holds information related to the communication quality of the entire wireless LAN of the system shown in FIG. FIG. 17 is a diagram illustrating an example of a data structure of communication quality information. For convenience of explanation, FIG. 17 shows communication quality based on a frame transmitted between the terminal α and AP1 to AP4. As shown in FIG. 17, the communication quality information 248 includes a selected capture device, a measurement start time, a measurement end time, the number of frames, the number of retries, an average bit rate, a maximum rate, a signal strength, Correlate roaming status with capture data comparison field.

  The selected capture device is information for identifying the capture device that has best received a frame transmitted / received between the AP1 to AP4 and the terminal α in the corresponding measurement slot time (time from the measurement start time to the measurement end time). It is. The measurement start time is the time when the measurement of the frame is started, and the measurement end time is the time when the measurement of the frame is ended.

  The number of frames includes reception and transmission. The reception of the number of frames indicates the number of frames received by the terminal α from AP1 to AP4. Reception of each measurement slot time is calculated by equation (2). In Formula (2), FXαAP1 is the number of frames transmitted from AP1 to the terminal α. FXαAP2 is the number of frames transmitted from AP2 to terminal α. FYαAP3 is the number of frames transmitted from AP3 to the terminal α. FYαAP4 is the number of frames transmitted from AP4 to the terminal α. In addition, “X” and “Y” included in Expression (2) are information for identifying the capture device 100 that has received the frame satisfactorily, “X” indicates the capture device 100X, and “Y” is the capture device. 100Y is shown. The same applies to the equations shown below.

  Frame number reception = FXαAP1 + FXαAP2 + FYαAP3 + FYαAP4 (2)

  The transmission of the number of frames is the number of frames transmitted by the terminal α to AP1 to AP4. The transmission of each measurement slot time is calculated by equation (3). FXα in Expression (3) corresponds to the total number of transmission frames of the terminal α shown in FIG.

  Transmission of the number of frames = FXα (3)

  The number of retries includes reception and transmission. The reception of the number of retries indicates the number of retries when AP1 to AP4 transmit a frame to the terminal α. Reception of each measurement slot time is calculated by equation (4). RetryXαAP1 indicates the number of retries when a frame is transmitted from AP1 to the terminal α. RetryXαAP2 indicates the number of retries when a frame is transmitted from AP2 to terminal α. RetryYαAP3 indicates the number of retries when a frame is transmitted from AP3 to terminal α. RetryYαAP4 indicates the number of retries when a frame is transmitted from AP4 to terminal α.

  Retry number reception = RetryXαAP1 + RetryXαAP2 + RetryYαAP3 + RetryYαAP4 (4)

  The transmission of the number of retries indicates the number of retries when the terminal α transmits a frame to AP1 to AP4. The transmission of each measurement slot time is calculated by equation (5). RetryXα in equation (5) corresponds to the number of transmission retries of terminal α shown in FIG.

  Transmission of the number of retries = RetryXα (5)

  The average bit rate has reception and transmission. The reception of the average bit rate indicates the average bit rate when AP1 to AP4 transmit frames to the terminal α. Reception of each measurement slot time is calculated by equation (6). The description regarding FXαAP1 to FXαAP4 is the same as that described in Expression (1). RateXαAP1 indicates an average bit rate when a frame is transmitted from AP1 to the terminal α. RateXαAP2 indicates an average bit rate when a frame is transmitted from AP2 to terminal α. RateYαAP3 indicates an average bit rate when a frame is transmitted from AP3 to terminal α. RateYαAP4 indicates an average bit rate when a frame is transmitted from AP4 to terminal α.

  Reception of average bit rate = (FXαAP1 * RateXαAP1 + FXαAP2 * RateXαAP2 + FYαAP3 * RateYαAP3 + FYαAP4 * RateYαAP4) / (FXαAP1 + FXαAP2 + FYαAP3 + FYαAP4) (6)

  The transmission of the average bit rate indicates the average bit rate when the terminal α transmits a frame to AP1 to AP4. The transmission of each measurement slot time is calculated by equation (7). RateXα in Expression (7) corresponds to the transmission average rate of terminal α shown in FIG.

  Average bit rate transmission = RateXα (7)

  The maximum rate has reception and transmission. The reception of the maximum rate indicates the maximum bit rate among the bit rates when AP1 to AP4 transmit frames to the terminal α. Reception of each reception slot time is calculated by the equation (8). In Equation (8), PeakXαAP1 indicates the maximum bit rate of a frame transmitted from AP1 to terminal α. PeakXαAP2 indicates the maximum bit rate of a frame transmitted from AP2 to terminal α. PeakYαAP3 indicates the maximum bit rate of a frame transmitted from AP3 to terminal α. PeakYαAP4 indicates the maximum bit rate of a frame transmitted from AP4 to terminal α.

  Maximum rate reception = Max (PeakXαAP1, PeakXαAP2, PeakYαAP3, PeakYαAP4) (8)

  The maximum rate transmission indicates the maximum bit rate among the bit rates when the terminal α transmits frames to AP1 to AP4. The transmission of each measurement slot time is calculated by equation (9). PeakXα in equation (9) corresponds to the maximum transmission rate of terminal α shown in FIG.

  Maximum rate transmission = PeakXα (9)

  The signal strength indicates the signal strength when the terminal α transmits a frame. For example, the signal intensity is “RssiXα”.

  The roaming status indicates the number of frames transmitted and received between the terminal α and AP1 to AP4. For example, the roaming status includes the number of frames transmitted and received between the terminal α and AP1, the number of frames transmitted and received between the terminal α and AP2, the number of frames transmitted and received between the terminal α and AP3, and the terminal α. And the number of frames transmitted and received between AP4 and AP4.

  The number of frames transmitted / received between the terminal α and AP1 is calculated by Expression (10). In formula (10), FXαAP1 is the same as described above. FXAP1α is the number of frames transmitted from the terminal α to AP1.

  Number of frames transmitted / received between terminal α and AP1 = FXαAP1 + FXAP1α (10)

  The number of frames transmitted / received between the terminal α and AP2 is calculated by the equation (11). In formula (11), FXαAP2 is the same as described above. FXAP2α is the number of frames transmitted from the terminal α to AP2.

  Number of frames transmitted / received between terminal α and AP2 = FXαAP2 + FXAP2α (11)

  The number of frames transmitted / received between the terminal α and the AP 3 is calculated by Expression (12). In Formula (12), FXαAP3 is the same as described above. FXAP3α is the number of frames transmitted from the terminal α to AP3.

  Number of frames transmitted and received between terminal α and AP3 = FYαAP3 + FXAP3α (12)

  The number of frames transmitted / received between the terminal α and the AP 4 is calculated by Expression (13). In Formula (13), FXαAP4 is the same as described above. FXAP4α is the number of frames transmitted from the terminal α to the AP4.

  Number of frames transmitted and received between terminal α and AP4 = FYαAP4 + FXAP4α (13)

  The capture data comparison column has information on the number of frames received by the capture device 100X and the capture device 100Y, respectively, out of the total number of transmission frames of the terminal α. Further, it has a signal output from the terminal α when the capture device 100X captures a frame and a signal output from the terminal α when the capture device 100Y captures a frame.

  The number of frames received by the capture device 100X from the terminal α is “FXα”. The number of frames received by the capture device 100Y from the terminal α is “FYα”. When the capture device 100X captures a frame, the signal output from the terminal α is “RssiXα”. The signal output from the terminal α when the capture device 100Y captures the frame is “RssiYα”.

  Returning to the description of FIG. The control unit 250 includes an acquisition unit 251, a preprocessing unit 252, a selection unit 253, and an analysis unit 254. The control unit 250 corresponds to, for example, an integrated device such as an ASIC or FPGA. Moreover, the control part 250 respond | corresponds to electronic circuits, such as CPU and MPU, for example.

  The acquisition unit 251 is a processing unit that acquires analysis data and capture data from the capture device 100 via the interface unit 210. The acquisition unit 251 is a processing unit that registers the acquired analysis data and capture data in the capture table 241 in association with the identification information of the capture device 100 that is the transmission source.

  The pre-processing unit 252 is a processing unit that generates an AP list 242, a terminal list 243, an AP characteristic synthesis table 244, a terminal frame table 245, a downlink frame table 246, and an uplink frame table 247 based on the capture table 241.

  An example of processing in which the preprocessing unit 252 generates the AP list 242 based on the capture table 241 will be described. FIG. 18 is a diagram for explaining processing in which the preprocessing unit generates an AP list. In FIG. 18, an AP list 132X is an AP list acquired from the capture device 100X. The AP list 132Y is an AP list acquired from the capture device 100Y. The pre-processing unit 252 generates the AP list 242 by merging the AP list 132X and the AP list 132Y according to an AND condition. The preprocessing unit 252 stores the generated AP list 242 in the storage unit 240.

  An example of processing in which the preprocessing unit 252 generates the terminal list 243 based on the capture table 241 will be described. FIG. 19 is a diagram for explaining processing of generating a terminal list by the preprocessing unit. In FIG. 19, the terminal list 133X is a terminal list acquired from the capture device 100X. The terminal list 133Y is a terminal list acquired from the capture device 100Y. The preprocessing unit 252 generates the terminal list 243 by merging the terminal list 133X and the terminal list 133Y according to the AND condition.

  The preprocessing unit 252 counts the number of extracted terminals based on the terminal list 243. The number of terminals corresponds to the number of types of MAC addresses (number of records) in the terminal list 243. When the number of terminals is equal to or greater than NS, the preprocessing unit 252 deletes the record of the low priority terminal from the terminal list 243 until the number of terminals becomes less than NS.

  For example, the preprocessing unit 252 compares the MAC address of the terminal list 243 and the capture data of the capture table 241 and counts the number of frames transmitted and received for each terminal. The preprocessing unit 252 determines that a terminal with a higher number of frames transmitted and received is a terminal with a higher priority. That is, the preprocessing unit 252 sorts terminals having a large number of frames transmitted and received, and leaves the NS-th terminal record in the terminal list 243 from the top.

  An example of a process in which the preprocessing unit 252 generates the AP specific combination table 244 will be described. Based on the capture table 241, the preprocessing unit 252 identifies the AP frame transmission number and AP signal strength of the capture device 100 for each AP, and sets the identified information in the determination tables 244a to 244d in FIG. To do.

  An example of processing in which the preprocessing unit 252 identifies the number of AP frames transmitted and the AP signal strength of the capture device 100X in the determination table 244a will be described. The preprocessing unit 252 acquires the capture data acquired from the capture device 100X from the capture table 241. The preprocessing unit 252 scans the capture data using the MAC address of AP1 as a key, and specifies the number of AP frames transmitted and the AP signal strength of the capture device 100X.

  An example of processing in which the preprocessing unit 252 specifies the number of AP frames transmitted and the AP signal strength of the capture device 100Y in the determination table 244a will be described. The preprocessing unit 252 acquires the capture data acquired from the capture device 100Y from the capture table 241. The preprocessing unit 252 scans the capture data using the MAC address of AP1 as a key, and specifies the number of AP frames transmitted and the AP signal strength of the capture device 100Y.

  The preprocessing unit 252 generates determination tables 244b to 244d related to AP2 to AP4 in the same manner as the determination table 244a. Note that, when the preprocessing unit 252 generates the determination tables 244a to 244d, the information of the selected capture device is blank. Information of the selected capture device is set by the selection unit 253 described later.

  Next, an example of processing in which the preprocessing unit 252 generates the terminal frame table 246 will be described. As illustrated in FIG. 13, for example, the terminal frame table 245 includes communication quality tables 245a and 245b. A process in which the preprocessing unit 252 generates the communication quality table 245a will be described. The preprocessing unit 252 refers to the terminal list 243 and identifies the MAC address of the terminal α. The preprocessing unit 252 compares the MAC address of the terminal α with the capture data acquired from the capture device 100X, and extracts the frame captured by the capture device 100X and frame attribute information.

  The preprocessing unit 252 identifies the total number of transmission frames, the number of transmission retries, the transmission average rate, the maximum transmission rate, and the signal output based on the extracted frame and attribute information. The preprocessing unit 252 sets each identified information in the communication quality table 245a. Similarly, the preprocessing unit 252 generates the communication quality table 245b.

  Next, an example of processing in which the preprocessing unit 252 generates the downlink frame table 246 will be described. As illustrated in FIGS. 14 and 15, for example, the downlink frame table 246 includes tables 246Xa to 246Xd and 246Ya to 246Yd.

  A process in which the preprocessing unit 252 generates the table 246Xa will be described. The preprocessing unit 252 identifies the MAC address of AP1 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. Based on the MAC address of AP1 and the MAC address of the terminal α, the preprocessing unit 252 extracts the frame transmitted from the AP1 to the terminal α from the capture data acquired from the capture device 100X. Based on the extracted frame, the preprocessing unit 252 specifies the number of AP1 → terminal α frames for each measurement time slot and registers the number in the table 246Xa.

  Similarly, the preprocessing unit 252 extracts the frames transmitted from the AP2 to AP4 to the terminal α from the capture data acquired from the capture device 100X. Based on the extracted frame, the preprocessing unit 252 specifies the number of AP2-AP4 → terminal α frames for each measurement time slot, and registers them in the table 246Xa.

  A process in which the preprocessing unit 252 generates the table 246Xb will be described. The preprocessing unit 252 identifies the MAC address of AP1 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. The preprocessing unit 252 extracts the frame and attribute information transmitted from the AP1 to the terminal α from the capture data acquired from the capture device 100X based on the MAC address of AP1 and the MAC address of the terminal α. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies the AP1 → terminal α retry frame number for each measurement time slot and registers the number in the table 246Xb.

  Similarly, the preprocessing unit 252 extracts the frame and attribute information transmitted from the AP2 to AP4 to the terminal α from the capture data acquired from the capture device 100X. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies the number of AP2-AP4 → terminal α retry frames for each measurement time slot, and registers the number in the table 246Xb.

  A process in which the preprocessing unit 252 generates the table 246Xc will be described. The preprocessing unit 252 identifies the MAC address of AP1 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. The preprocessing unit 252 extracts the frame and attribute information transmitted from the AP1 to the terminal α from the capture data acquired from the capture device 100X based on the MAC address of AP1 and the MAC address of the terminal α. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies AP1 → terminal α average bit rate for each measurement time slot, and registers it in the table 246Xc.

  Similarly, the preprocessing unit 252 extracts the frame and attribute information transmitted from the AP2 to AP4 to the terminal α from the capture data acquired from the capture device 100X. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies AP2 to AP4 → terminal α average bit rate for each measurement time slot, and registers it in the table 246Xc.

  A process in which the preprocessing unit 252 generates the table 246Xd will be described. The preprocessing unit 252 identifies the MAC address of AP1 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. The preprocessing unit 252 extracts the frame and attribute information transmitted from the AP1 to the terminal α from the capture data acquired from the capture device 100X based on the MAC address of AP1 and the MAC address of the terminal α. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies AP1 → terminal α maximum bit rate for each measurement time slot, and registers it in the table 246Xd.

  Similarly, the preprocessing unit 252 extracts the frame and attribute information transmitted from the AP2 to AP4 to the terminal α from the capture data acquired from the capture device 100X. Based on the extracted frame and attribute information, the preprocessing unit 252 specifies AP2 to AP4 → terminal α maximum bit rate for each measurement time slot, and registers them in the table 246Xc.

  The process for generating the pre-processing unit 252 tables 246Ya to 246Yd differs in that the frame and attribute information is extracted from the capture data acquired from the capture device 100Y, but the other processes are the processes for generating the tables 246Xa to Xd. It is the same.

  Subsequently, a process in which the preprocessing unit 252 generates the uplink frame table 247 will be described. As shown in FIG. 16, the upstream frame table 247 includes tables 247Xa and 247Ya.

  A process in which the preprocessing unit 252 generates the table 247Xa will be described. The preprocessing unit 252 identifies the MAC addresses of AP1 to AP4 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. Based on the MAC addresses of AP1 to AP4 and the MAC address of the terminal α, the preprocessing unit 252 extracts the frame transmitted from the terminal α to the AP1 to AP4 from the capture data acquired from the capture device 100X. Based on the extracted frames, the preprocessing unit 252 specifies the number of frames of the terminal α → AP1 to AP4 for each measurement time slot and registers the number in the table 247Xa.

  A process in which the preprocessing unit 253 generates the table 247Ya will be described. The preprocessing unit 252 identifies the MAC addresses of AP1 to AP4 with reference to the AP list 242 and identifies the MAC address of the terminal α with reference to the terminal list 243. Based on the MAC addresses of AP1 to AP4 and the MAC address of the terminal α, the preprocessing unit 252 extracts a frame transmitted from the terminal α to the AP1 to AP4 from the capture data acquired from the capture device 100Y. Based on the extracted frame, the preprocessing unit 252 specifies the number of frames of the terminal α → AP1 to AP4 for each measurement time slot and registers the number in the table 247Ya.

  When the preprocessing unit 253 executes the above processing, the AP list 242, the terminal list 243, the AP characteristic synthesis table 244, the terminal frame table 245, the downlink frame table 246, and the uplink frame table 247 are generated.

  The selection unit 253 is a processing unit that selects a capture device that has best captured a frame for each measurement slot time. The analysis unit 254 described later generates communication quality information 248 based on the frame captured by the capture device selected by the selection unit 253.

  An example of processing of the selection unit 253 will be described. The selection unit 253 may refer to the AP characteristic synthesis table 244 to select a capture device with a larger number of AP frame transmissions or a capture device with a higher AP signal strength.

  A process in which the selection unit 253 selects a capture device for each measurement slot time based on the number of AP frame transmissions will be described. For example, the record on the first line of the determination table 244a will be described. The measurement slot time of this record is “November 24, 2015 16:45 to 2015 November 24, 17:00”. In this record, the AP frame transmission count of the capture device 100X is “100”, and the AP frame transmission count of the capture device 100Y is “80”. Therefore, the selection unit 253 selects the capture device 100X and registers it in the selected capture device of the record in the first row. The selection unit 253 repeatedly executes the above process for other records.

  A process in which the selection unit 253 selects a capture device for each measurement slot time based on the AP signal strength will be described. For example, the record on the first line of the determination table 244a will be described. The measurement slot time of this record is “November 24, 2015 16:45 to 2015 November 24, 17:00”. In this record, the AP signal strength of the capture device 100X is “−61 (dBm)”, and the AP signal strength of the capture device 100Y is “−78 (dBm)”. Therefore, the selection unit 253 selects the capture device 100X and registers it in the selected capture device of the record in the first row. The selection unit 253 repeatedly executes the above process for other records.

  Note that the selection unit 253 may select the capture device by combining the number of AP frame transmissions and the AP signal strength.

  In addition, the selection unit 253 identifies a capture device that has successfully received a frame transmitted from the terminal based on the terminal frame table 245 and sets it as information of the selected capture device for each measurement slot time of the communication quality information 248. . For example, referring to the terminal frame table 245 of FIG. 13, the capture device 100 that has received many frames transmitted from the terminal α becomes the capture device 100X. Therefore, the selection unit 253 sets “capture device 100X” as the selected capture device for each measurement slot time of the communication quality information 248.

  Note that the selection unit 253 may select the capture device by combining the number of frame transmissions transmitted from the terminal and the terminal signal strength.

  The analysis unit 254 is a processing unit that generates the communication quality information 248 based on the frame captured by the capture device selected by the selection unit 253. For example, the analysis unit 254 generates communication quality information 248 based on the terminal frame table 245, the downlink frame table 246, and the uplink frame table 247.

  Although not described below, referring to the AP characteristic synthesis table 244 in FIG. 12, the capture device that has successfully received the frames transmitted from the AP1 and AP2 to the terminal α is the selected capture device “capture device 100X”. The capture device that has successfully received the frames transmitted from the AP3 and AP4 to the terminal α is the selected capture device “capture device 100Y”. As shown in the selective capture device of FIG. 17, a capture device that successfully captures frames transmitted from the terminal α to each of the AP1 to AP4 is referred to as a “capture device 100X”.

  An example of processing in which the analysis unit 254 generates the communication quality information 248 will be described. A process in which the analysis unit 254 sets the “reception of the number of frames” information of the communication quality information 248 will be described. The analysis unit 254 calculates “reception of the number of frames” based on the above equation (2), and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets information of “transmission of the number of frames” of the communication quality information 248 will be described. The analysis unit 254 calculates “transmission of the number of frames” based on the above equation (3), and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets the “retry number reception” information of the communication quality information 248 will be described. The analysis unit 254 calculates “reception of the number of retries” based on the above formula (4), and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets information of “transmission of retry count” in the communication quality information 248 will be described. Based on the above equation (5), the analysis unit 254 calculates “retry number transmission” and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets information of “reception of average bit rate” in the communication quality information 248 will be described. The analysis unit 254 calculates “reception of average bit rate” based on the above equation (6), and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets information of “transmission of average bit rate” of the communication quality information 248 will be described. The analysis unit 254 calculates “average bit rate transmission” based on the equation (7), and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets the “maximum rate reception” information of the communication quality information 248 will be described. Based on the above equation (8), the analysis unit 254 calculates “maximum rate reception” and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets the “maximum rate transmission” information of the communication quality information 248 will be described. The analysis unit 254 calculates “maximum rate transmission” based on the above equation (9) and sets it in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets “signal strength” information of the communication quality information 248 will be described. The analysis unit 254 sets the value of “RssiXα” in the communication quality information 248. The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets “roaming status” information of the communication quality information 248 will be described. The analysis unit 254 sets the number of frames transmitted / received between the terminal α and the AP 1 based on Expression (10). The analysis unit 254 sets the number of frames transmitted and received between the terminal α and the AP 2 based on the equation (11). The analysis unit 254 sets the number of frames transmitted / received between the terminal α and the AP 3 based on Expression (12). The analysis unit 254 sets the number of frames transmitted / received between the terminal α and the AP 4 based on Expression (13). The analysis unit 254 repeatedly executes the above process for other records.

  A process in which the analysis unit 254 sets information of the “capture data comparison field” will be described. The analysis unit 254 extracts relevant information based on the terminal frame table 245 and sets the extracted information in the “capture data comparison field”.

  Note that the communication quality information 248 illustrated in FIG. 17 indicates the communication quality information between the AP1 to AP4 and the terminal α, but the communication quality information between the AP1 to AP4 and the terminals β and γ can be generated in the same manner. .

  After generating the communication quality information 248, the analysis unit 254 generates an average bit rate graph, a maximum rate graph, a retry rate graph, and a roaming situation graph. The analysis unit 254 outputs the information of the communication quality information 248 and the information of each generated graph to the display unit 230 for display. Further, the analysis unit 254 may calculate the radio wave occupancy based on Expression (1) instead of the capture device 100. The analysis unit 254 may generate a radio wave occupation rate graph and cause the display unit 230 to display the generated graph.

  Next, a processing procedure of the capture device 100 according to the present embodiment will be described. FIG. 20 is a flowchart illustrating the processing procedure of the capture apparatus according to the present embodiment. As illustrated in FIG. 20, the frame acquisition unit 110 of the capture device 100 captures a frame transmitted and received between the AP and the terminal (step S101). The radio wave occupation rate calculation unit 142 of the capture device 100 calculates the radio wave occupation rate for each measurement slot time (step S102).

  The list creation unit 143 of the capture device 100 creates the AP list 132 and the terminal list 133 for each measurement slot time (step S103). The statistical information generation unit 144 of the capture device 100 extracts the AP signal strength and the total number of transmission frames for each measurement slot time for the AP (step S104). The transmission unit 145 of the capture device 100 transmits analysis data and capture data to the measurement device 200 (step S105).

  Next, a processing procedure of the measuring apparatus 200 according to the present embodiment will be described. FIG. 21 is a flowchart illustrating the processing procedure of the measurement apparatus according to the present embodiment. As illustrated in FIG. 21, the acquisition unit 251 of the measurement device 200 acquires analysis data and capture data from each capture device 100 (step S201).

  The preprocessing unit 252 of the measuring apparatus 200 determines a terminal to be analyzed from the analysis data (step S202). The preprocessing unit 252 determines all APs roaming with the analysis target terminal as analysis target APs (step S203). The preprocessing unit 252 generates a radio wave occupancy graph for each point (step S204).

  The preprocessing unit 252 merges the AP lists received from the capture devices 100 to generate the AP list 242 (step S205). The preprocessing unit 252 merges the terminal lists received from the capture devices 100 to generate the terminal list 243 (step S206).

  The selection unit 253 of the measurement apparatus 200 selects an optimal frame for each individual AP for each measurement slot time (step S207). In step S207, for example, the selection unit 253 refers to the AP characteristic synthesis table 244 illustrated in FIG. 12 to select the capture device 100 that has received the frames transmitted from the AP1 to AP4 best, and selects the selected capture. The frame captured by the device 100 is selected.

  The preprocessing unit 252 generates the terminal frame table 245 (step S208). The preprocessing unit 252 generates the downlink frame table 246 (step S209). The preprocessing unit 252 generates an uplink frame table (step S210).

  The analysis unit 254 of the measuring apparatus 200 generates communication quality information 248 (step S211). The analysis unit 254 generates a graph (step S212), and displays the communication quality information 248 and the graph on the display unit 230 (step S213).

  Next, the effect of the measuring apparatus 200 according to the present embodiment will be described. When the measurement apparatus 200 acquires frames transmitted from the same AP and terminal in the same time zone from the plurality of capture apparatuses 100 arranged at different points, the measurement apparatus 200 receives the frame among the plurality of capture apparatuses 100. Select the frame on the selected side and perform the analysis. For this reason, it is possible to efficiently evaluate the communication quality of the wireless LAN over a wide range.

  The measuring apparatus 200 selects a frame captured by the capture apparatus 100 having the strongest transmission radio wave intensity from the AP or the capture apparatus having the largest number of frames captured from the AP. For this reason, it is possible to appropriately select the frame on the side that received well.

  The frame captured by the capture device is a frame transmitted from a preset access point and a frame transmitted from an access point commonly used by terminal devices that exchange frames with the preset access point. . For this reason, it is possible to appropriately narrow down the frames to be analyzed, and the burden on the measuring apparatus 200 can be reduced.

  In addition, the measuring apparatus 200 calculates a radio wave occupation rate, a bit rate, and a retry rate based on attribute information of a frame transmitted from the AP to the terminal and a frame transmitted from the terminal to the AP. For this reason, it is possible to appropriately calculate communication quality information.

  The measuring apparatus 200 further analyzes the roaming situation between the terminal and the plurality of access points based on the frame. For this reason, it becomes possible to notify the administrator of the roaming information of the terminal.

  By the way, among the processes described in the present embodiment, all or a part of the processes described as being automatically performed can be manually performed, or the processes described as being performed manually can be performed. All or a part can be automatically performed by a known method. In addition, the processing procedure, control procedure, specific name, and information including various data and parameters shown in the above-described document and drawings can be arbitrarily changed unless otherwise specified.

  Furthermore, each processing function performed by each device may be realized by a CPU and a program that is analyzed and executed by the CPU, or may be realized as hardware by wired logic.

100X, 100Y Capture device 200 Measuring device

Claims (8)

At a plurality of different points, acquisition units that respectively acquire the frames from a plurality of capture devices that acquire frames transmitted and received by wireless communication between the access point and the terminal device;
In the plurality of frames acquired by the acquisition unit, when there are a plurality of frames transmitted from the same access point in the same time zone, the frame that is determined to be the best received by the capture device is selected. When there are a plurality of frames transmitted from the same terminal in the same time zone, a selection unit that selects a frame that is determined to be received best by the capture device;
An analysis unit that analyzes communication quality based on the frame selected by the selection unit.   The selection unit selects a capture device having the strongest transmission radio wave intensity from the access point, or a frame captured by a capture device having the largest number of frames captured from the access point, and transmission from the terminal. 2. The measuring apparatus according to claim 1, wherein a frame captured by a capture apparatus having the highest radio field intensity or a capture apparatus having the largest number of frames captured from the terminal is selected.   The frame captured by the capture device is a frame transmitted from a preset access point and a frame transmitted from an access point commonly used by terminal devices that exchange frames with the preset access point. The measuring apparatus according to claim 1 or 2, wherein   The analysis unit calculates a radio wave occupation rate of each channel used in the wireless communication, a bit rate of the frame, and a retry rate of the frame for each time based on attribute information of a plurality of frames. The measuring apparatus according to claim 1, 2, or 3.   The analysis unit calculates the radio wave occupation rate, bit rate, and retry rate based on a frame transmitted from the access point to the terminal device, and displays the calculation result. Measuring device.   The analysis unit calculates the radio wave occupation rate, bit rate, and retry rate based on a frame transmitted from the terminal device to the access point, and displays the calculation result. Measuring device.   The measurement device according to claim 1, wherein the analysis unit further analyzes a roaming state between the terminal device and a plurality of access points based on the frame. A measurement method performed by a computer,
At a plurality of different points, each of the frames is acquired from a plurality of capture devices that acquire frames transmitted and received by wireless communication between the access point and the terminal device,
In the acquired frames, when there are multiple frames transmitted from the same access point in the same time zone, and when there are multiple frames transmitted from the same terminal in the same time zone Selects the frame that the capture device is deemed to have received best,
A measurement method characterized by executing processing for analyzing communication quality based on a selected frame.

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