JP4855340B2 - Area map construction system that creates area maps based on communication quality information - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an area map build up system which does not apply a load to the whole network by reducing the number of times for transmitting communication quality information from a general wireless terminal as much as possible when a database server makes an area map based on the communication quality information. <P>SOLUTION: A database server determines a measurement area range information specifying an area where the number of pieces of communication quality information becomes a predetermined threshold or less, and transmits a measurement request including the measurement area range information and measurement quality range information to a wireless terminal. The wireless terminal judges whether communication area information based on the position of the wireless terminal itself is included in the measurement area range information included in the received measurement request and/or weather the communication quality information is included in the measurement quality range information or not. If the judgment is true, a measurement response including current position information and communication quality information is answered to the database server. <P>COPYRIGHT: (C)2009,JPO&amp;INPIT

Description

  The present invention relates to an area map construction system for creating an area map based on communication quality information for a wireless communication system.

  A communication carrier of a wireless communication system needs to collect communication quality information from wireless terminals distributed in a wide area in order to grasp the communication quality state in the service area. And the communication quality state of the whole service area is understood by creating the area map using the communication quality information matched for every position.

  First, in order to easily collect communication quality information in a service area, there is a technique of installing measurement wireless terminals that collect communication quality information at various positions in the area (see, for example, Patent Document 1). The measurement wireless terminal detects communication quality information with the base station periodically or at any time, and transmits it to the personal computer via the network. The area status display device connected to the personal computer displays the communication quality status of the area.

  Second, there is a technique in which a general wireless terminal transmits communication quality information in actual communication to a database server via a wireless link (see, for example, Patent Document 2). The wireless terminal has a positioning function such as GPS (Global Positioning System), and transmits current position information and communication quality information to a database server. The database server stores communication quality information associated with the positioning position in a database. Next, the database server notifies the wireless terminal of the types of communication media that can be used at that location. If the wireless terminal is a communication medium having a higher priority than the currently used communication medium, the wireless terminal activates the communication interface. As a wireless terminal, since it is not always necessary to activate a plurality of communication interfaces and perform a search, the power consumption of the battery can be reduced.

  Thirdly, there is a technique in which a wireless terminal includes two communication media, a wireless LAN interface and a PHS interface, and a wireless LAN notification server is connected to a PHS network (see, for example, Patent Document 3). According to this technology, when communication via a wireless LAN interface is possible, the wireless terminal transmits a wireless LAN area ID (IDentifier) and a PHS base station ID to the wireless LAN notification server via the PHS network. . The wireless LAN notification server knows that the area of the PHS base station ID can communicate with the wireless LAN based on the wireless LAN area ID. That is, the PHS base station ID and the wireless LAN area ID are linked and stored. Thereafter, when another wireless terminal is communicating with the PHS base station, the wireless LAN notification server notifies the other wireless terminal when the PHS base station ID is within the previously stored wireless LAN area. In contrast, control information for switching to the wireless LAN is transmitted.

  Fourth, there is a technique in which a wireless terminal transmits a message to that effect and position information to a server when the received signal strength of a radio wave from a base station becomes a predetermined threshold value or less (see Non-Patent Document 1, for example). The server creates, as an area map, a position where the received signal strength of the radio wave is equal to or less than a predetermined threshold. The area map is transmitted to the wireless terminal. The wireless terminal predicts the remaining area time from the current position information to the low received signal strength area, and starts the handover process when the time becomes equal to or less than the threshold value.

  Fifth, there is a technique in which a wireless terminal stores abnormal information (time, communication quality information, position) when a communication abnormality occurs even though radio waves from the base station can be detected (for example, (See Patent Document 4). After the communication is restored, the wireless terminal transmits communication quality information when a communication abnormality occurs to a management server connected to the network.

JP 2003-032174 A JP 2006-060295 A Japanese Patent Laying-Open No. 2005-086451 Japanese Patent No. 3588056 JieZhang, Henry C. B. Chan and Victor C. M. Leung, “ASIP-based Seamless-handoff (S-SIP) Scheme for Heterogeneous Mobile Networks,” WCNC2007, Mar. 2007.

  According to the technique described in Patent Literature 1, the range of the area where communication quality information can be acquired varies depending on the number of measurement wireless terminals installed. In order to collect communication quality information over a wide area without any gaps, it is necessary to install a huge number of measurement wireless terminals, which is inevitably expensive. In addition, when collecting communication quality information from a large number of measurement radio terminals, the amount of radio resources consumed and the power consumption of the battery of the measurement radio terminals also become problems.

  According to the technique described in Patent Literature 2, it is not necessary to install a specific measurement wireless terminal in order for a general wireless terminal to acquire communication quality information. However, since a large number of general wireless terminals are used, the acquisition information becomes enormous, the load on the database server increases, and the consumption of wireless resources required to transmit the acquisition information to the database server becomes a problem. Become. Moreover, in order to acquire the current position information of the wireless terminal, it is necessary to activate a positioning function such as GPS every time. When the positioning function is activated, the battery consumes a lot of power. Therefore, increasing the number of times that the wireless terminal transmits the communication quality information activates the positioning function of the wireless terminal, resulting in a decrease in the remaining battery level.

  According to the technique described in Patent Document 3, since radio waves for the wireless LAN are not transmitted outside the area where the wireless LAN can be used, it is advantageous in terms of effective use of the battery and the wireless resources. In addition, since the positioning function such as GPS is not activated, the battery usage can be further reduced. However, as long as there are wireless terminals in the wireless LAN area, information to the wireless LAN notification server continues to be notified. Therefore, the problem of wasted wireless resources and the processing load of the wireless LAN notification server are not eliminated. In addition, this technology promotes effective use of a wireless LAN network using a PHS network, and a communication carrier does not create an area map based on communication quality information for the entire service area.

  According to the technique described in Patent Document 4, the received signal strength of the radio wave is notified to the server only when a communication abnormality occurs, which is advantageous in terms of effective use of the battery and radio resources. However, this technology assumes a wide area mobile communication system (wireless MAN) such as a cellular phone network. When a narrow communication area such as a wireless LAN (MAN) is mixed in a wide communication area, communication abnormality notifications from wireless terminals may occur frequently.

  As described above, according to the prior art, the wireless terminal actively transmits the communication quality information to the database server. Therefore, the database server has an area range that is necessary and an area range that is not necessary when creating an area map. For example, this is a case where an area range where a lot of communication quality information is collected and an area range where a little amount of communication quality information can be collected. In this case, the database server desires communication quality information from a wireless terminal located there for an area range where only a small amount of communication quality information can be collected. In addition, as a database server, it is desired to avoid an increase in processing load and compression of radio resources due to data transmission concentrated from a huge number of radio terminals within a certain period of time.

  Further, since the wireless terminal transmits the current position information and the communication quality information as data, it consumes a large amount of battery power. It is not preferable from the viewpoints of battery power consumption and radio resources to frequently transmit communication quality information to a general wireless terminal used by a user just to collect the communication quality information.

  The wireless terminal needs to activate a positioning function such as GPS in order to measure the current position. Frequent activation of GPS for a general wireless terminal used by a user is also not preferable from the viewpoint of battery power consumption.

Accordingly, the present invention is, depending on the database server can collect only the information needed to create an area map based on the communication quality information, as much as possible the number of transmission of the communication quality information in a wireless terminal of General The purpose is to provide an area map construction system that reduces and does not impose a load on the entire network.

According to the present invention,
For each area, a database server having an area map creation means for creating an area map in which communication quality information is mapped to each position;
A plurality of cellular base stations for mobile communications;
Multiple access points for high-speed wireless communication;
In an area map construction system having a mobile communication interface that communicates with a cellular base station, a high-speed wireless communication interface that communicates with an access point, and a plurality of wireless terminals that have positioning means for positioning current position information,
The database server
Measurement area range information for specifying an area where the number of communication quality information is equal to or less than a predetermined threshold value and measurement quality range information indicating a measurement range of communication quality are determined , and the measurement quality range information is a radio terminal The mobile communication interface is set to have a communication quality range that is less than or equal to the communication boundary with the cellular base station, and the wireless terminal's high-speed wireless communication interface can communicate with the access point. Measuring range control means for setting a range of high communication quality higher than the level representing ,
A measurement request transmission means for transmitting a measurement request including measurement area range information and measurement quality range information to a wireless terminal;
Measurement response receiving means for receiving a measurement response including current position information and communication quality information from a wireless terminal;
Wireless terminal
Communication quality information storage means for storing communication quality information from the base station and access point measured by the mobile communication interface and the high-speed wireless communication interface, respectively ;
A measurement request receiving means for receiving a measurement request;
The measurement area range information included in the measurement request includes communication area information based on the position of the wireless terminal itself , and the measurement quality range information for each communication interface included in the measurement request includes the communication area information of the wireless terminal. Measurement range determination means for determining whether or not communication quality information of the communication interface is included ;
When the determination by the measurement range determination unit is true, the measurement range determination unit includes a measurement response transmission unit that returns a measurement response including current position information and communication quality information to the database server.

According to another embodiment of the area map construction system of the present invention,
It is also preferable that the measurement range control means controls to repeatedly transmit a measurement request to a desired wide measurement area while changing the measurement quality range information for each measurement area range information.

According to another embodiment of the area map construction system of the present invention,
Communication quality information is reception quality, number of retransmissions or data error rate,
The measurement quality range information is also preferably a predetermined range of communication quality information.

According to another embodiment of the area map construction system of the present invention, the communication area information includes latitude / longitude / altitude / radius information, a map classification identifier divided into predetermined ranges, a base station identifier, an SSID (Service Set IDentifier). ), Pilot PN (Pseudo Noise) value, or base station MAC (Media Access Control) address,
The measurement area range information is also preferably one or more communication area information.

  According to another embodiment of the area map construction system of the present invention, it is preferable that the wireless terminal further includes a measurement area range storage unit that stores measurement area range information included in the measurement request.

According to another embodiment of the area map construction system of the present invention,
The positioning means of the wireless terminal is positioning based on a communicable cellular base station,
When the determination by the measurement range determination unit in the wireless terminal is true, it is preferable to further include a positioning control unit that activates GPS (Global Positioning System) and performs positioning.

According to another embodiment of the area map construction system of the present invention,
Regarding the wireless terminal, it is also preferable that the positioning control means does not activate GPS when the remaining battery level of the wireless terminal is equal to or less than a predetermined threshold.

  According to the area map construction system of the present invention, in order to create an area map based on communication quality information, the database server specifies measurement area range information with a small amount of information and receives communication quality information only from wireless terminals within that range. Therefore, the number of times of transmission of communication quality information in a general wireless terminal is reduced as much as possible, and the entire network including the wireless section is not loaded. This is also effective from the viewpoint of reducing the power consumption of the battery of the wireless terminal. In addition, data transmission from wireless terminals is not concentrated on the database server, and the load on the database server can be reduced.

  Further, according to the present invention, the wireless terminal can also determine the communication identifier and the communication quality information before starting the positioning function in response to the positioning request from the database server. Therefore, by collecting only necessary information, the number of times of starting the positioning function and transmitting the communication quality information in a general wireless terminal can be reduced as much as possible. This is effective from the viewpoint of reducing the power consumption of the battery of the wireless terminal.

  Hereinafter, the best mode for carrying out the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a system configuration diagram according to the present invention.

According to the communication system of FIG. 1, a plurality of base stations 3 that cover a service area of a communication carrier are connected to a mobile communication network 4. The base station 3 may correspond to different types of communication media. For example, it is a cellular base station for a cellular communication network and an access point for a high-speed wireless communication network (wireless LAN or IEEE 802.16). Range covered by a plurality of base stations 3 are placed in the carrier's area map. FIG. 1 shows a cellular communication area 31 and a wireless LAN area 32.

  The base station 3 communicates with a plurality of wireless terminals 1 via wireless links. The wireless terminal 1 may include wireless communication interfaces for different types of communication media. For example, the cellular communication interface is connected to a cellular base station, and the high-speed wireless communication interface is connected to an access point. The wireless terminal 1 also has a positioning function for detecting radio waves from the GPS satellite 6 and positioning current position information. The current position information is represented by, for example, latitude / longitude / altitude.

A database server (LAS-DB (Location Information and Available System Information Data Base)) 2 is connected to the mobile communication network 4 via an IP network 5. The database server 2 accumulates communication quality information associated with a position in order to create an area map based on the communication quality information. The communication quality information includes, for example, reception quality, number of retransmissions, or data error rate. The reception quality to be described below, for example, RSS (Receive d S ignal Strength: received signal strength), C / I (interference ratio), a Ec / Io (adjacent base station transmit level to the current base station transmit level).

  FIG. 2 is an area map based on communication quality information.

  According to the upper diagram of FIG. 2, a map is arranged on the xy axis, and the positions of a plurality of base stations 3 are also superimposed. The z-axis represents communication quality information, and the higher the value, the better the communication quality. The communication quality information in good condition is when the received signal strength is high, the signal-to-interference noise ratio is small, the number of retransmissions is small, or the data error rate is low. On the other hand, the bad communication quality information is when the received signal strength is small, the signal-to-interference noise ratio is large, the number of retransmissions is large, or the data error rate is high.

  According to the upper diagram of FIG. 2, a pyramid-like hierarchy is represented around the base station 3. This indicates that the closer to the base station 3, the better the communication quality. Further, these hierarchies represent a certain range of communication quality information (measurement quality range information). According to the upper diagram of FIG. 2, a narrow-area wireless LAN area is also shown for a plurality of wide-area cellular communication area information. If the communication provider can create an area map as shown in the upper diagram of FIG. 2, the communication quality corresponding to the position of the wireless terminal can be grasped, which can be used for facility design and service quality improvement.

  Further, according to the lower diagram of FIG. 2, the positioning result includes the altitude in addition to the latitude and longitude. For example, an area map as shown in the upper diagram of FIG. 2 can be created for each altitude classified in the lower diagram of FIG. Thereby, even if it is the same latitude longitude, when communication quality information changes with the floors of a building, it can be handled as communication quality information according to each height.

  FIG. 3 is an explanatory diagram showing classification of communication area information in the map.

  According to the upper diagram of FIG. 3, the communication area information is divided for each base station ID. Communication area information A to E is represented for each base station, and the number of communication quality information is recorded for each communication area. According to the upper diagram of FIG. 3, since the communication area information B and D has the number of communication quality information equal to or less than a predetermined threshold, the database server determines the communication area information B and D as the measurement area range. And collect further communication quality information. In addition to the base station ID, classification can also be performed by SSID, pilot PN value, or base station MAC address.

  According to the lower diagram of FIG. 3, the communication area information is divided for each predetermined range of the map. Communication area information a to f is represented for each fixed range, and the number of communication quality information is recorded for each communication area. According to the lower diagram of FIG. 3, since the communication area information c has the number of pieces of communication quality information equal to or less than a predetermined threshold, the database server determines the communication area information c as a measurement area range, and further communication. Collect quality information.

  FIG. 4 is an area map in the present invention.

  According to FIG. 4, with respect to the cellular communication area information, positions are plotted for a certain range (measurement quality range information) where the communication quality information is bad, that is, a certain height range where the z-axis is low. The plot of bad communication quality information usually gathers at a position away from the base station 3. That is, as the measurement quality range information is set to a lower range with respect to the z-axis, it means that the boundary portion of the cellular communication area information is represented.

  On the other hand, for the wireless LAN area, the positions are plotted for a certain range (measurement quality range information) where the communication quality information is good, that is, a certain height range where the z-axis is high. It means that the availability of the wireless LAN increases as the measurement quality range information is set to a higher range with respect to the z-axis.

  FIG. 5 is a first sequence diagram in the present invention.

(S401) The GPS satellite transmits a radio wave for positioning.
(S402) The wireless terminal 1 receives radio waves from GPS satellites and performs positioning. The positioning result is latitude and longitude. This current position information is stored as communication area information.
(S403) Further, the wireless terminal 1 detects communication quality information with the base station 3. Communication quality information includes received signal strength, signal-to-interference noise ratio, number of retransmissions, or data error rate. The wireless terminal 1 stores the detected communication quality information.

(S404) The database server 2 determines measurement area range information in the area map to be measured. The measurement area range information may be latitude / longitude / altitude / radius information, a map segment identifier, a base station identifier, an SSID, a pilot PN value, or a base station MAC address segmented for each predetermined range. However, it is of the same type as the communication area information.

  The measurement area range information specifies an area where the number of communication quality information is equal to or less than a predetermined threshold. For example, the map may be divided into predetermined ranges and the number of communication quality information for each division may be used. In addition, the number of collected communication quality information is searched for each base station, and the base station ID (base station ID, SSID, pilot PN value or base station MAC address) whose number is equal to or less than a predetermined threshold is measured. It may be determined as area range information. Further, when the map is divided for each predetermined range, the ID of the base station to which the division whose number of communication quality information is equal to or less than a predetermined threshold may be determined as the measurement area range information. There may be one measurement area range information or a plurality of pieces of information for designating a wide area. In addition, a measurement object / measurement exclusion flag can be added to the measurement area range information. In the case of “Measurement target”, it is determined whether or not the communication area information is included in the measurement area range information. In the case of “Measurement exclusion”, it is determined whether or not the communication area information is included in the measurement area range information. The

(S405) Next, the database server 2 specifies measurement quality range information. The measurement quality range information is a predetermined range of received signal strength, signal-to-interference noise ratio, number of retransmissions, or data error rate. In the case of received signal strength, it is specified in a range such as -xdB to -ydB. In the case of the number of retransmissions, it is specified in a range such as an average number of retransmissions x times to y times (may be a decimal point). For example, by setting x times or more, only wireless terminals having an average number of retransmissions of x times or more are targeted. It is also preferable to set relatively poor measurement quality range information for the cellular communication area information and relatively good measurement quality range information for the wireless LAN area.

(S406) The database server 2 transmits a measurement request to the wireless terminal 1 by broadcast. The measurement request includes measurement area range information and measurement quality range information, and is received by a plurality of base stations 3. The measurement request is also preferably transmitted by multicast after grouping specific models.
(S407) Upon receiving the measurement request from the database server 2, the base station 3 broadcasts to the plurality of wireless terminals 1. When the measurement request is transmitted by multicast, the base station 3 transmits the target wireless terminal 1 by multicast or unicast.

(S408) Upon receiving the measurement request, the wireless terminal 1 compares the measurement area range information included in the measurement request with the communication area information stored in S402. If the communication area information is not included in the measurement area range information, no processing is performed. However, if the “measurement exclusion” flag is set, conversely, if the communication area information is included in the measurement area range information, no processing is performed. Next, when the communication area information is included in the measurement area range information, the measurement quality range information included in the measurement request is compared with the communication quality information stored in S403. When the communication quality information is not included in the measurement quality range information, no processing is performed. At this time, it is also preferable that no processing be performed even when the remaining battery level of the wireless terminal is equal to or less than a predetermined threshold. Do not collect communication quality information from wireless terminals with low battery power. In addition, when GPS positioning fails indoors, it is also preferable to postpone subsequent GPS activation for a preset time. The wireless terminal 1 preferably stores the measurement area range information and the measurement quality range information, and moves to S410 when moving to the corresponding place.

  5 skips S409, and FIG. 6 explains S409.

(S410) When it is determined that the wireless terminal 1 is a measurement object in S408, the wireless terminal 1 transmits a measurement response to be returned to the database server 2 to the base station 3. The measurement response includes the current position information and the communication quality information detected in S403.
(S411) Receiving the measurement response, the base station 3 transmits the measurement response to the database server 2.

(S412) Upon receiving the measurement response, the database server 2 accumulates communication quality information associated with the current position information. And it is determined whether it measures about ranges other than the measurement quality range information included in the measurement request transmitted previously. For example, bad measurement quality range information may be measured in order from good measurement quality range information. When measuring the next range, the process returns to S405 again. At this time, it is also preferable to return to S405 after waiting for a preset time. By inserting the identifier into the measurement request, the identifiers are made the same in the case of the same measurement area range, and the measurement area range information may not be included in the measurement request. In this case, the wireless terminal 1 that has received the measurement request for the first time ignores the measurement request.
(S413) Next, the database server 2 determines whether to measure a range other than the measurement area range information included in the previously transmitted measurement request. For example, a measurement area range in which a predetermined number or more of communication quality information cannot be collected may be measured again. When measuring the next base station, the process returns to S404 again. At this time, it is also preferable to return to S404 after waiting for a preset time.

(S414) Finally, the database server 2 creates an area map as shown in FIG. 2 or FIG. For example, a map such as a topographic map is created with the communication quality information as the vertical axis. By looking at this area map, the communication carrier can grasp the communication quality based on the position.

  FIG. 6 is a second sequence diagram in the present invention.

  In the following, only the portions of the sequence in FIG. 6 that are different from those in FIG. 5 will be described. Processes other than S401, S402, and S409 are the same as those in FIG.

(S401) The base station 3 periodically transmits a beacon signal (or paging channel). The beacon signal includes a communication ID (IDentifier) of the base station 3. The communication ID becomes communication area information. The communication ID may be a base station identifier, an SSID, a pilot PN value, or a base station MAC address.
(S402) The wireless terminal 1 that has received the beacon signal recognizes that it can communicate with the base station 3 based on the communication ID (communication area information). The wireless terminal 1 stores the communication ID.

(S409) If the communication area information (communication ID) is included in the measurement area range information (for example, measurement ID), the wireless terminal 1 activates the GPS positioning function and starts positioning the current position information. Latitude and longitude are obtained as positioning results.

  According to the sequence of FIG. 6, the wireless terminal determines the communication identifier and the communication quality information before starting the positioning function in response to the positioning request from the database server. Therefore, in order to activate GPS only when returning a measurement response, the number of times of activation of the positioning function and transmission of communication quality information can be reduced as much as possible. This is effective from the viewpoint of reducing the power consumption of the battery of the wireless terminal.

  If the database server includes, as the measurement area range information, latitude / longitude / altitude / radius information or an identifier for each map section divided for each predetermined range together with the base station ID, first, in S408, the base station It is also preferable to activate the GPS and compare the latitude / longitude / altitude / radius or the identifier for each section only when the station IDs are compared and the own station is connected to the base station.

  FIG. 7 is a functional configuration diagram of the wireless terminal according to the present invention.

  7, the wireless terminal 1 includes a communication interface unit 101, a positioning unit 102, a communication area storage unit 103, a communication quality information storage unit 104, a measurement request reception unit 105, and a measurement range determination unit 106. , Positioning control unit 107, measurement response transmission unit 108, data transmission / reception unit 109, and measurement area range storage unit 110. These functional components can also be realized by executing a program that causes a computer installed in the wireless terminal 1 to function. The data transmitting / receiving unit 109 represents an existing data transmitting / receiving function of the wireless terminal.

  The communication interface unit 101 is an interface that communicates with a base station via a wireless link. The communication interface unit 101 may include a plurality of interfaces of different communication media types. According to FIG. 7, it has a cellular communication interface and a wireless LAN interface. The cellular communication interface communicates with a cellular base station via a wireless link, and the wireless LAN interface communicates with an access point via a wireless link.

  The positioning unit 102 is based on GPS, receives radio waves from the GPS satellite 6, and measures current position information. The current position information is latitude / longitude information. If four satellites can be captured, altitude information can be acquired in addition to latitude and longitude. The measured current position information is transferred to the measurement response transmission unit 108. The current position information is also transferred to the measurement range determination unit 106 as communication area information.

  The communication area storage unit 103 stores the communication ID (SSID, pilot PN value, or base station MAC address) of the base station detected by the communication interface unit 101. Although not shown in FIG. 7, the communication area storage unit 103 may store the current position information measured by the positioning unit 102. The stored communication area information is transferred to the measurement range determination unit 106.

  The communication quality information storage unit 104 stores communication quality information measured by the communication interface unit 101. The stored communication quality information is transferred to the measurement range determination unit 106.

  The measurement request receiving unit 105 receives a measurement request including measurement area range information and measurement quality range information from the database server 2 by broadcasting. The measurement area range information and the measurement quality range information are transferred to the measurement range determination unit 106.

  The measurement range determination unit 106 determines whether the communication area information is included in the measurement area range information and / or whether the communication quality information is included in the measurement quality range information. However, when the “measurement exclusion” flag is added, it is determined whether the communication area information is not included in the measurement area range information. If both determinations are true, the positioning control unit 107 is continued.

  The positioning control unit 107 activates the positioning unit 102 when the determination by the measurement range determination unit 106 is true. However, the positioning control unit 107 does not start positioning means when the remaining battery level of the wireless terminal is equal to or less than a predetermined threshold.

  The measurement response transmission unit 108 returns a measurement response including the current position information measured by the positioning unit 102 and the communication quality information to the database server 2.

  The measurement area range storage unit 110 stores measurement area range information output from the measurement request reception unit 105. Thereby, even if a fixed time has passed or moved after receiving the measurement request, the measurement response can be transmitted based on the stored measurement area range information.

  FIG. 8 is a functional configuration diagram of the database server in the present invention.

  The database server 2 accumulates communication quality information associated with the position, and creates an area map based on the communication quality information. As shown in FIG. 8, the database server 2 includes a measurement range control unit 201, a measurement request transmission unit 202, a measurement response reception unit 203, an area map creation unit 204, and a communication interface unit 205. These functional units can also be realized by executing a program that causes a computer mounted on the database server to function.

  The measurement range control unit 201 determines measurement area range information specifying an area where the number of communication quality information is equal to or less than a predetermined threshold. The measurement quality range information is changed while changing the measurement area range information for a desired wide measurement area. The measurement range controller 201 sets the measurement quality range information to a low communication quality range for the cellular communication interface of the wireless terminal, and the measurement quality range information for the wireless LAN interface of the wireless terminal. Control to set to a range of high communication quality.

  The measurement request transmission unit 202 transmits a measurement request including measurement area range information and measurement quality range information determined by the measurement range control unit 201 to the plurality of wireless terminals 1 by broadcast. When grouping measurement target terminals, they are transmitted by multicast.

  The measurement response receiving unit 203 receives a measurement response from the wireless terminal 1. The measurement response includes the current location information and communication quality information of the wireless terminal.

  The area map creation unit 204 creates the area map for the measurement area by mapping the communication quality information to the position of the current location information of the wireless terminal included in the measurement response.

  As described above in detail, according to the area map construction system of the present invention, the database server specifies the measurement area range information with a small amount of information and creates the range in order to create the area map based on the communication quality information. Since the communication quality information can be received only from the wireless terminal, the number of times of transmission of the communication quality information in the general wireless terminal is reduced as much as possible, and the entire network is not loaded. This is also effective from the viewpoint of reducing the power consumption of the battery of the wireless terminal. In addition, data transmission from wireless terminals is not concentrated on the database server, and the load on the database server can be reduced.

  Further, according to the present invention, the wireless terminal can also determine the communication identifier and the communication quality information before starting the positioning function in response to the positioning request from the database server. Therefore, by collecting only necessary information, the number of times of starting the positioning function and transmitting the communication quality information in a general wireless terminal can be reduced as much as possible. This is effective from the viewpoint of reducing the power consumption of the battery of the wireless terminal.

  According to the various embodiments of the present invention described above, those skilled in the art can easily make various changes, modifications and omissions within the scope of the technical idea and the viewpoint of the present invention. The above description is merely an example, and is not intended to be restrictive. The invention is limited only as defined in the following claims and the equivalents thereto.

It is a system configuration diagram in the present invention. It is an area map based on communication quality information. It is explanatory drawing showing the division of the communication area information in a map. It is an area map in the present invention. It is a 1st sequence diagram in this invention. It is a 2nd sequence diagram in this invention. It is a function block diagram of the radio | wireless terminal in this invention. It is a functional block diagram of the database server in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Wireless terminal 101 Communication interface part 102 Positioning part 103 Communication area memory | storage part 104 Communication quality information memory | storage part 105 Measurement request | requirement receiving part 106 Measurement range determination part 107 Positioning control part 108 Measurement response transmission part 109 Data transmission / reception part 2 Database server 201 Measurement range Control unit 202 Measurement request transmission unit 203 Measurement response reception unit 204 Area map creation unit 205 Communication interface unit 3 Base station, cellular base station, access point 31 cellular communication area 32 wireless LAN area 4 mobile communication network 5 IP network 6 GPS satellite

Claims (7)

For each area, a database server having an area map creation means for creating an area map in which communication quality information is mapped to each position;
A plurality of cellular base stations for mobile communications;
Multiple access points for high-speed wireless communication;
In an area map construction system having a mobile communication interface that communicates with the cellular base station, a high-speed wireless communication interface that communicates with the access point, and a plurality of wireless terminals that have positioning means for positioning current position information,
The database server is
Measuring area range information for identifying an area where the number of the communication quality information is equal to or less than a predetermined threshold, and measurement quality range information indicating a measurement range of communication quality , the measurement quality range information, For the mobile communication interface of the wireless terminal, set one having a low communication quality range below the degree representing the communication boundary with the cellular base station, and access to the high-speed wireless communication interface of the wireless terminal. Measuring range control means for setting a range of communication quality that is higher than the degree representing communication with a point; and
A measurement request transmitting means for transmitting a measurement request including the measurement area range information and the measurement quality range information to the wireless terminal;
Measurement response receiving means for receiving a measurement response including the current position information and communication quality information from the wireless terminal;
The wireless terminal is
Communication quality information storage means for storing communication quality information from a base station and an access point measured by each of the mobile communication interface and the high-speed wireless communication interface ;
A measurement request receiving means for receiving the measurement request;
The measurement area range information included in the measurement request includes communication area information based on the position of the wireless terminal itself , and the measurement quality range information for each communication interface included in the measurement request includes Measurement range determination means for determining whether or not communication quality information of the communication interface of the wireless terminal is included ;
An area map construction system, comprising: a measurement response transmission unit that returns a measurement response including the current position information and the communication quality information to the database server when the determination by the measurement range determination unit is true. The measurement range control means controls to repeatedly transmit the measurement request to a desired wide measurement area while changing measurement quality range information for each measurement area range information. Area Map construction system described in 1. The communication quality information is reception quality, number of retransmissions or data error rate,
The area map construction system according to claim 1 or 2 , wherein the measurement quality range information is a predetermined range of the communication quality information. The communication area information includes latitude / longitude / altitude / radius information, a map section identifier, a base station identifier, an SSID (Service Set IDentifier), a pilot PN (Pseudo Noise) value, or a base station. MAC (Media Access Control) address,
The area map construction system according to any one of claims 1 to 3 , wherein the measurement area range information is one or more pieces of the communication area information. The wireless terminal area map construction system according to any one of claims 1 to 4, characterized by further comprising a measurement area range storage means for storing the measurement area range information included in the measurement request. The positioning means of the wireless terminal is positioning based on a communicable cellular base station,
If the determination of the measuring range determining means in the wireless terminal is true, GPS (Global Positioning System) and activates any one of claims 1, characterized by further comprising a positioning controller for positioning 5 The area map construction system described in 1. The area map construction system according to claim 6 , wherein the positioning control unit does not activate the GPS when the remaining battery level of the wireless terminal is equal to or less than a predetermined threshold.

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