JP2012060432A - Neighboring cell processing apparatus and neighboring cell processing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a neighboring cell processing apparatus and a neighboring cell processing method that can streamline the operation of a radio communication system by generating appropriate neighboring cell information.SOLUTION: The neighboring cell processing apparatus includes: a measurement information acquisition section 11 for acquiring measurement information indicating measurement results of radio signals transmitted from a plurality of radio base station apparatuses other than a target radio base station apparatus on the basis of information from at least either a radio terminal apparatus or the radio base station apparatuses; and a neighboring cell information generation section 12 for generating neighboring cell information indicating one or more radio base station apparatuses deployed around the target radio base station apparatus out of the plurality of radio base station apparatuses other than the target radio base station apparatus on the basis of the measurement information acquired by the measurement information acquisition section 11.

Description

  The present invention relates to an adjacent cell processing apparatus and an adjacent cell processing method, and more particularly to an adjacent cell processing apparatus and an adjacent cell processing method in a communication system capable of communicating with a plurality of radio base station apparatuses by a mobile terminal performing a moving operation. .

  Conventionally, in a mobile communication system, a communication service is provided by a radio base station apparatus (hereinafter also referred to as a macro base station) that forms an area in which a cell having a radius of several hundred meters to several tens of kilometers, that is, a radio terminal apparatus can communicate. It was.

  In recent years, due to a dramatic increase in the number of subscribers of mobile communication services and an increase in the amount of communication traffic due to data communication, subscribers and communication traffic are distributed by forming smaller radius cells, and a certain level of communication It is desirable to provide speed to users in a stable manner. In addition, in order to deal with dead zones associated with the increase in the number of buildings, it is desired to install radio base station devices on the corporate floor and in ordinary households.

  Together with these demands, the processing capability of various devices used in the radio base station apparatus has been dramatically improved, and the miniaturization of the radio base station apparatus has progressed. Collecting.

  Since the radius of the femto cell (Femto Cell) formed by this small base station (hereinafter also referred to as a femto base station) is as small as about 10 meters, the femto base station is the macro cell (Macro Cell) formed by the macro base station. It can be used in places such as homes and underground malls that are outside the service area and where it is difficult to install macro base stations.

  In addition, since many femto base stations are installed in a specific area, it is difficult to connect the femto base stations directly to the core network. For this reason, it is conceivable that a large number of femto base stations installed in a specific area are once connected to a gateway device such as a HeNB-GW, and the femto base station and the core network are connected via the HeNB-GW.

  In such a configuration, when an operator or a purchaser of a femto base station performs setting of each femto base station when installing the femto base station, considerable work and cost are required. Further, every time a femto base station is newly installed and the number of femto base stations is increased, not only newly installed femto base stations but also existing surrounding femto base stations must be reset.

  As a configuration for solving such problems, for example, Patent Document 1 discloses the following technique. That is, the new cell measures the signal strength of various different channels used by the existing cell. The new cell creates a list of candidate channels corresponding to channels with high signal strength and transmits this list to the mobile switching center of the cellular system. The mobile switching center determines which candidate channel corresponds to the beacon used in the existing cell and transmits configuration information about each of these existing cells to the new cell. Thus, the new cell automatically receives configuration information regarding neighboring cells. If the mobile switching center determines that the identified neighbor (adjacent cell) has not reached the maximum value N, then the mobile switching center will add additional candidate channels (ie, more (Candidate channel with low signal strength) is requested to be transmitted.

JP-A-11-333131

  The purchaser of the femto base station can uniquely determine the installation location of the femto base station. For this reason, in a radio communication system in which a femto base station is installed, the femto base station is likely to move and the power is turned on / off. Therefore, appropriate neighboring cell information in the radio base station apparatus in which the femto base station exists in the vicinity. It becomes difficult to generate.

  For example, the wireless terminal device measures the received power from the femto base station registered in the neighboring cell information autonomously or in accordance with an instruction from the femto base station using the neighboring cell information, and uses the measurement result. Report to femto base station. In this case, if a femto base station that is not suitable as a handover destination is registered in the neighboring cell information, the wireless terminal device performs a useless measurement operation, and a useless handover occurs.

  The present invention has been made to solve the above-described problems, and an object of the present invention is to provide an adjacent cell processing apparatus capable of increasing the efficiency of operation in a wireless communication system by generating appropriate adjacent cell information. And providing a neighbor cell processing method.

  (1) In order to solve the above-described problem, an adjacent cell processing apparatus according to an aspect of the present invention is an adjacent cell processing in a communication system in which a wireless terminal apparatus can communicate with a plurality of wireless base station apparatuses by performing a moving operation. Measurement information indicating measurement results of radio signals transmitted from a plurality of radio base station apparatuses other than the target radio base station apparatus from at least one of the radio terminal apparatus and the radio base station apparatus. Among the plurality of radio base station apparatuses other than the target radio base station apparatus, based on the measurement information acquired by the measurement information acquisition section for acquiring based on information and the measurement information acquisition section, the above A neighboring cell information generating unit for generating neighboring cell information indicating one or a plurality of the wireless base station devices arranged around the target wireless base station device; The adjacent cell information generated by the information generation unit and a neighbor cell information transmitting unit for transmitting to the communicable wireless terminal devices with the target radio base station apparatus or said target radio base station apparatus.

  With such a configuration, it is possible to automatically optimize neighboring cell information regardless of movement of the radio base station apparatus and power on / off, so that operation of the radio communication system can be performed without human intervention. Efficiency can be improved. In addition, since the neighboring cell information is automatically optimized, a special installation process for the radio base station apparatus is not required, so that the work time and cost for installing the radio base station apparatus can be reduced. Can do.

  Therefore, by generating appropriate neighboring cell information, it is possible to improve the efficiency of the operation in the radio communication system.

  (2) Preferably, the neighboring cell information generation unit ranks a plurality of the radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. Next, neighboring cell information based on the ranking result is generated.

  With such a configuration, it is possible to generate detailed neighboring cell information and further improve the efficiency of the operation in the radio communication system. For example, the radio base station apparatus can increase the success rate of the movement operation by preferentially selecting a higher-level radio base station apparatus as a movement destination in the ranking result.

  (3) More preferably, the adjacent cell information generation unit indicates adjacent cells indicating N (N is an integer of 1 or more) of the radio base station devices from the top among the plurality of ranked radio base station devices. Generate information.

  With such a configuration, for example, when there is a limit to the number of radio base station apparatuses that can be included in the neighboring cell information notified to the radio terminal apparatus, the top N radio base station apparatuses can be included in the neighboring cell information. Thus, it is possible to notify the appropriate wireless cell apparatus of adjacent cell information.

  (4) More preferably, the neighboring cell information generation unit generates neighboring cell information further indicating the ranking of the ranked radio base station devices.

  With such a configuration, it is possible to generate more detailed neighboring cell information and further improve the efficiency of the operation in the radio communication system. For example, the radio terminal apparatus can perform an efficient measurement operation by determining the measurement order and narrowing down the radio base station apparatuses to be measured according to the rank of the radio base station apparatus in the neighboring cell information.

  (5) Preferably, the measurement information acquisition unit sets a reception level of a radio signal transmitted from a plurality of the radio base station apparatuses other than the target radio base station apparatus to the radio terminal apparatus and the radio base station apparatus. Measurement information indicating a result of measurement by at least one is acquired based on information from at least one of the wireless terminal device and the wireless base station device.

  Thus, appropriate neighboring cell information can be generated by including which radio base station device is included in the neighboring cell information and using the reception level as a criterion for ranking the radio base station devices.

  (6) More preferably, the neighboring cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. Then, in the ranking, the rank of the radio base station apparatus having a high reception level indicated by the measurement information is raised higher than that of the radio base station apparatus having a small reception level.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses according to the actually measured reception level.

  (7) More preferably, the neighboring cell information generation unit is configured to transmit the radio in which the reception level indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus. The neighboring cell information excluding at least the base station apparatus is generated.

  With such a configuration, it is possible to appropriately delete a radio base station apparatus having a low actually measured reception level from the neighboring cell information.

  (8) Preferably, the measurement information acquisition unit includes at least one of the radio terminal device and the radio base station device based on radio signals transmitted from a plurality of radio base station devices other than the target radio base station device. Measurement information indicating the number of times one detects the presence of the radio base station apparatus is acquired based on information from at least one of the radio terminal apparatus and the radio base station apparatus.

  In this way, appropriate neighbor cell information is generated by using which radio base station device is included in the neighbor cell information and using the number of times the radio base station device is detected as a criterion for ranking the radio base station device. be able to.

  (9) More preferably, the neighboring cell information generation unit ranks a plurality of the radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. Then, in the ranking, the rank of the radio base station apparatus having the large number of detections indicated by the measurement information is raised as compared with the radio base station apparatus having the small number of detections.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses according to the actual results of detection of existence. That is, it is possible to recognize a radio base station apparatus that is powered on and a radio base station apparatus that is powered off, and generate appropriate neighboring cell information.

  (10) More preferably, the neighboring cell information generation unit is configured to transmit the radio in which the number of detections indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus. The neighboring cell information excluding at least the base station apparatus is generated.

  With such a configuration, it is possible to appropriately delete a radio base station apparatus that is actually detected and has a small track record from the neighboring cell information. That is, it is possible to recognize a radio base station apparatus that is powered on and a radio base station apparatus that is powered off, and generate appropriate neighboring cell information.

  (11) Preferably, the measurement information acquisition unit includes at least one of the radio terminal device and the radio base station device based on radio signals transmitted from a plurality of radio base station devices other than the target radio base station device. Measurement information indicating a detection rate at which one detects the presence of the radio base station apparatus is acquired based on information from at least one of the radio terminal apparatus and the radio base station apparatus.

  In this way, by generating which neighbor cell information is included in the neighbor cell information and using the detection rate of the radio base station device as a criterion for determining the ranking of the radio base station device, appropriate neighbor cell information is generated Can do. Here, the detection rate is a ratio of the number of times that the wireless terminal device detects the presence of the wireless base station device to the number of times the wireless terminal device has performed the measurement.

  (12) More preferably, the neighboring cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. Then, in the ranking, the rank of the radio base station apparatus with the large detection rate indicated by the measurement information is raised over the rank of the radio base station apparatus with the small detection rate.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses according to the actual results of detection of existence. That is, it is possible to recognize a radio base station apparatus that is powered on and a radio base station apparatus that is powered off, and generate appropriate neighboring cell information.

  (13) More preferably, the neighboring cell information generation unit is configured to transmit the radio in which the detection rate indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus. The neighboring cell information excluding at least the base station apparatus is generated.

  With such a configuration, it is possible to appropriately delete a radio base station apparatus that is actually detected and has a small track record from the neighboring cell information. That is, it is possible to recognize a radio base station apparatus that is powered on and a radio base station apparatus that is powered off, and generate appropriate neighboring cell information.

  (14) Preferably, the measurement information acquisition unit includes measurement information indicating a measurement time when the latest measurement result that is the basis for the addition or remaining of the radio base station device to the neighboring cell information is obtained. Obtained based on information from at least one of the wireless terminal device and the wireless base station device.

  In this way, by using which radio base station device is included in the neighboring cell information and the elapsed time from the measurement time as a criterion for determining the ranking of the radio base station device, the radio base that is unlikely to exist at the present time The station apparatus can be recognized and appropriate neighboring cell information can be generated.

  (15) More preferably, the neighboring cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. In the ranking, the rank of the radio base station apparatus having a long elapsed time from the measurement time is lowered than that of the radio base station apparatus having a short elapsed time from the measurement time.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses according to the possibility of existing at the present time.

  (16) More preferably, the neighboring cell information generation unit is configured to cause the radio base station in which an elapsed time from the measurement time is a predetermined value or more among a plurality of the radio base station apparatuses other than the target radio base station apparatus. The neighboring cell information excluding at least the station apparatus is generated.

  With such a configuration, a radio base station apparatus that is unlikely to exist at the present time can be appropriately deleted from the neighboring cell information.

  (17) Preferably, at least one of the plurality of radio base station apparatuses in the communication system is a femto base station.

  As described above, by generating appropriate neighboring cell information in a wireless communication system in which movement of the wireless base station device and power on / off frequently occur, the effect of improving the operation efficiency in the wireless communication system is more remarkable. Can get to.

  (18) Preferably, the neighboring cell information generation unit includes a movement destination candidate of a wireless terminal device communicating with the target wireless base station device among a plurality of the wireless base station devices other than the target wireless base station device. Neighboring cell information indicating one or a plurality of the radio base station apparatuses is generated.

  With this configuration, it is possible to optimize the movement operation within the cell of the installed radio base station apparatus. In addition, by optimizing neighboring cell information, the number of neighboring cells that are candidates for the destination of the wireless terminal device in communication can be reduced, so that it is possible to prevent unnecessary movement operations from occurring. .

  (19) Preferably, the neighboring cell information generation unit includes one or a plurality of the radio base stations to be measured by the radio terminal device among the plurality of radio base station devices other than the target radio base station device. Neighbor cell information indicating the device is generated.

  In this way, by optimizing the neighboring cell information, the number of neighboring cells to be measured by the wireless terminal device can be reduced, thereby preventing the wireless terminal device from performing a useless measurement operation. be able to.

  (20) Preferably, the neighboring cell information generation unit transmits a radio signal for which the radio terminal device measures a reception level among the plurality of radio base station devices other than the target radio base station device. To generate neighboring cell information indicating one or a plurality of the radio base station apparatuses.

  In this way, by optimizing the neighboring cell information, the number of neighboring cells for which the wireless terminal device performs reception level measurement can be reduced, so that the wireless terminal device performs useless measurement operation. Can be prevented.

  (21) More preferably, the neighboring cell information generation unit receives the wireless terminal device not communicating with the target wireless base station device among the plurality of wireless base station devices other than the target wireless base station device. Neighbor cell information indicating one or a plurality of radio base station apparatuses that transmit a radio signal whose level is to be measured is generated.

  With such a configuration, the number of neighboring cells that are the targets of periodic power measurement indicated by broadcast information from the radio base station apparatus can be reduced, so that the radio terminal apparatus performs a useless measurement operation. Can be prevented. In particular, since the power consumption of the idle wireless terminal device can be reduced, a remarkable effect can be obtained.

  (22) Preferably, the neighboring cell information generation unit ranks a plurality of the radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit. The neighboring cell information generation unit generates neighboring cell information based on the ranking result, and the neighboring cell information generation unit is configured to cause the wireless terminal device communicating with the target wireless base station device to receive the wireless base station other than the target wireless base station device. Based on the result of measuring the reception level of the radio signal transmitted from the apparatus at a plurality of frequencies, the initial information of the neighboring cell information is generated.

  With such a configuration, it is possible to construct appropriate neighboring cell information at an early stage, and it is possible to realize an efficient operation in the radio communication system at an early stage.

  (23) More preferably, in the adjacent cell processing device, the target wireless base station device can further register the wireless terminal device, and the registered wireless terminal device and the unregistered wireless terminal device can be registered. When operating in a hybrid mode in which communication is permitted to both wireless terminal devices, the wireless base station device other than the target wireless base station device is transmitted to the wireless terminal device that is not registered. A power measurement instruction unit for instructing to measure the reception level of the wireless signal at the plurality of frequencies.

  With such a configuration, it is possible to prevent the power consumption of the wireless terminal device owned by the registered user from being consumed, so that an appropriate communication service can be provided.

  (24) More preferably, in the adjacent cell processing device, the target wireless base station device can register the wireless terminal device, and the registered wireless terminal device and the unregistered wireless device. When operating in a hybrid mode in which communication is permitted to both radio terminal apparatuses, the radio base station apparatus other than the target radio base station apparatus is transmitted to the registered radio terminal apparatus. A power measurement instruction unit is provided for instructing to measure the reception level of the radio signal at the plurality of frequencies.

  With such a configuration, it is possible to prevent the power consumption of the wireless terminal device owned by a non-registered user who often does not have an environment capable of immediately charging the wireless terminal device, so that an appropriate communication service is provided. Can be provided.

  (25) Preferably, the neighboring cell information generation unit allows the target radio base station apparatus to register the radio terminal apparatus, and the registered radio terminal apparatus and the unregistered radio terminal When operating in a hybrid mode that permits communication to both devices, measurement information indicating the measurement result by the registered wireless terminal device and measurement indicating the measurement result by the unregistered wireless terminal device Information is weighted, and the neighboring cell information is generated based on the weighted result.

  With this configuration, it is possible to generate appropriate neighboring cell information according to the registered wireless terminal device and the unregistered wireless terminal device.

  (26) Preferably, the said measurement information acquisition part acquires the measurement information which shows the said measurement result in the past fixed period from the present.

  With such a configuration, for example, it is possible to prevent the rank of a radio base station apparatus that has been powered off from being kept high forever.

  (27) Preferably, the adjacent cell processing device is included in one or a plurality of the radio base station devices.

  With such a configuration, for example, there is no need to optimize neighboring cell information of each radio base station device in the gateway device or the host device, and the processing load in the radio communication system is distributed, and the radio base station device and the gateway device or the host device. The amount of communication with the apparatus can be reduced.

  (28) In order to solve the above-described problem, an adjacent cell processing method according to an aspect of the present invention provides an adjacent cell processing in a communication system in which a wireless terminal device can communicate with a plurality of wireless base station devices by performing a moving operation. A method for obtaining measurement information indicating measurement results of radio signals transmitted from a plurality of radio base station devices other than the target radio base station device from at least one of the radio terminal device and the radio base station device. Obtained based on information, and based on the obtained measurement information, among a plurality of the radio base station devices other than the target radio base station device, arranged around the target radio base station device Generating neighboring cell information indicating one or a plurality of the radio base station apparatuses, and generating the neighboring cell information as the target radio base station apparatus or the pair And transmitting to the communicable wireless terminal and a wireless base station apparatus.

  With such a configuration, it is possible to automatically optimize neighboring cell information regardless of movement of the radio base station apparatus and power on / off, so that operation of the radio communication system can be performed without human intervention. Efficiency can be improved. In addition, since the neighboring cell information is automatically optimized, a special installation process for the radio base station apparatus is not required, so that the work time and cost for installing the radio base station apparatus can be reduced. Can do.

  Therefore, by generating appropriate neighboring cell information, it is possible to improve the efficiency of the operation in the radio communication system.

  According to the present invention, it is possible to improve the efficiency of operation in a wireless communication system by generating appropriate neighboring cell information.

It is a figure which shows the relationship between the wireless terminal device which can be connected with the access mode of the femto base station which concerns on the 1st Embodiment of this invention. It is a figure which shows the example of arrangement | positioning of the radio base station apparatus in the radio | wireless communications system which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the radio base station apparatus which concerns on the 1st Embodiment of this invention. It is a figure which shows the structure of the signal processing part which concerns on the 1st Embodiment of this invention. FIG. 10 is a diagram illustrating an example of a sequence in which a wireless base station device generates initial neighboring cell information in the wireless communication system according to the first embodiment of the present invention. In the radio | wireless communications system which concerns on the 1st Embodiment of this invention, it is a figure which shows an example of the sequence in which a radio base station apparatus acquires measurement information. It is a figure which shows an example of the sequence of the hand-over operation | movement in the radio | wireless communications system which concerns on the 1st Embodiment of this invention. It is a figure which shows an example of cell ID and a carrier frequency of each radio base station apparatus in the radio | wireless communications system shown in FIG. It is a figure which shows an example of the measurement information which the wireless base station apparatus acquired. It is a figure which shows an example of the adjacent cell information which a wireless base station apparatus produces | generates. It is a figure which shows the other example of the adjacent cell information which a wireless base station apparatus produces | generates. In the radio | wireless communications system which concerns on the 1st Embodiment of this invention, a radio base station apparatus is a figure which shows an example of the method which notifies neighboring cell information to a radio | wireless terminal apparatus. In the radio | wireless communications system which concerns on the 1st Embodiment of this invention, a radio base station apparatus is a figure which shows an example of the method which notifies neighboring cell information to a radio | wireless terminal apparatus. In the radio | wireless communications system which concerns on the 1st Embodiment of this invention, a radio base station apparatus is a figure which shows an example of the method which notifies neighboring cell information to a radio | wireless terminal apparatus. It is a figure which shows an example of the measurement result by the wireless terminal device. It is a figure which shows an example of the measurement information which the wireless base station apparatus acquired. It is a figure which shows an example of the adjacent cell information which a wireless base station apparatus produces | generates. It is a figure which shows the other example of the adjacent cell information which a wireless base station apparatus produces | generates. It is a figure which shows an example of the measurement information which the wireless base station apparatus acquired. It is a figure which shows an example of the adjacent cell information which a wireless base station apparatus produces | generates. It is a figure which shows the other example of the adjacent cell information which a wireless base station apparatus produces | generates. It is a figure which shows the structure of the radio | wireless communications system which concerns on the 4th Embodiment of this invention. It is a figure which shows the structure of the gateway apparatus which concerns on the 4th Embodiment of this invention. It is a figure which shows the structure of the data processing part in the gateway apparatus which concerns on the 4th Embodiment of this invention. It is a figure which shows the method with which the gateway apparatus which concerns on the 4th Embodiment of this invention notifies neighboring cell information.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<First Embodiment>
The radio base station apparatus notifies the radio terminal apparatus of information about the cell and the neighboring cell that it forms, that is, the frequency of the radio signal and the ID (identification) of the neighboring cell. The wireless terminal device detects and measures neighboring cells based on information notified from the wireless base station device. The wireless terminal device starts moving to the neighboring cell based on the measurement result. Here, “movement” of the wireless terminal device means not only handover but also through which cell the wireless terminal device in an idle state starts communication in the future, that is, when a call or data communication is started. This means selecting whether to perform communication.

  For example, when the wireless terminal device is communicating with the wireless base station device, the destination of the wireless terminal device is determined by the wireless base station device or a higher-level device in the core network. Further, when the wireless terminal device is not communicating with the wireless base station device, the wireless terminal device determines the destination of the wireless terminal device.

  The femtocell and access mode are described in 3GPP (Third Generation Partnership Project) SPEC TS 22.22 as follows. That is, a femto base station is a customer premises apparatus that connects a wireless terminal device connected via a wireless interface to a mobile communication carrier network using an IP backhaul.

  Further, in the femtocell access mode, the femto base station in the closed access mode provides a service only to related CSG (Closed Subscriber Group) members. Further, the femto base station in the hybrid access mode provides services to related CSG members and CSG non-members. The femto base station in the open access mode operates as a normal base station.

  Such a 3GPP definition may also be applied to the wireless communication system according to the first embodiment of the present invention.

  Further, the following definitions can be applied together with or separately from the above definitions.

  The macro base station is a radio base station device that is under the management of the operator and can communicate with the radio base station device that has contracted with the operator. In addition, it is considered that the macro base station is basically not turned off.

  A femto base station is a radio base station apparatus that is installed mainly in an individual or corporation building and may be turned off depending on the user's circumstances.

  Further, the femto base station operates in one of open / hybrid / closed access modes. When the femto base station operates in the closed access mode, only registered members (terminals) can be connected. When operating in the closed access mode, the service is provided only to registered members. When operating in the hybrid access mode, the service is provided to both registered members and unregistered members, that is, non-members. Further, when operating in the open access mode, the same operation as the macro base station is performed.

  FIG. 1 is a diagram illustrating a relationship between an access mode of a femto base station and a connectable wireless terminal apparatus according to the first embodiment of the present invention.

  Referring to FIG. 1, the femto base station according to the first embodiment of the present invention has three access modes. That is, in the closed access mode, only registered wireless terminal apparatuses can be connected to the femto base station. In the open access mode, the wireless terminal devices that can be connected to the femto base station are all wireless terminal devices, which are the same as those of a normal macro base station. In the hybrid mode, all the wireless terminal devices that can be connected to the femto base station are all wireless terminal devices. However, in the hybrid mode, a member, that is, a registered wireless terminal device, may be favored in terms of allocation of a communication resource of the femto base station, charging, and the like, compared to a non-member, that is, a wireless terminal device that is not registered.

  That is, the femto base station according to the first embodiment of the present invention can operate in an open access mode that permits communication for all wireless terminal devices, or can register wireless terminal devices, Operates in a closed access mode that allows communication to registered wireless terminal devices, or can register wireless terminal devices, both registered wireless terminal devices and unregistered wireless terminal devices It is possible to set whether to operate in a hybrid mode that permits communication.

  In a cell in the closed access mode, 3GPP stipulates that a wireless terminal device autonomously detects a neighboring cell. In addition, in a macro cell in the open access mode, when a business operator systematically installs a radio base station device, the business operator also knows information related to surrounding macro cells, and during installation and maintenance of the radio base station device. It is set at the time.

  By the way, since the user can install the femto base station at an arbitrary place, it is difficult for the femto base station to grasp the current location. For this reason, it is difficult for the femto base station to obtain information on neighboring cells.

  As described above, the femto cell detection method and the movement method of the wireless terminal device in the cell in the closed access mode are defined by 3GPP. However, when the wireless terminal device moves from the macro cell or the femto cell to the macro cell or the femto cell in the open access mode, the wireless base station device of the movement source notifies the wireless terminal device of the information of the wireless base station device of the movement destination. There is a need to.

  Here, since the use location of the femto base station is uniquely determined by the user, the femto base station may move and the power may be turned on / off. As a result, the following two problems become problems. That is, since the femto base station cannot grasp the current location, it is difficult to acquire information on cells arranged in the vicinity by the OAM function (maintenance function). In addition, when a femto base station exists in the vicinity of the radio base station apparatus and the femto base station is powered off, the radio terminal apparatus cannot move to the femto base station. It becomes necessary to detect the on / off state of the power source.

  Note that if the femto base station can identify the current location using GPS (Global Positioning System) or the like, the femto base station may inquire the carrier network to acquire information on cells that are geographically close. However, it is difficult to specify an accurate position due to the problem of accuracy.

[Configuration and basic operation]
FIG. 2 is a diagram illustrating an arrangement example of radio base station apparatuses in the radio communication system according to the first embodiment of the present invention.

  Referring to FIG. 2, a radio communication system 301 is a mobile communication system that complies with LTE (Long Term Evolution) standardized by 3GPP, for example, and includes radio base station apparatuses 101A, 101B, 101C, 101D, and 101E.

  In the wireless communication system 301, the wireless base station devices 101A, 101C, 101D, and 101E are femto base stations, and the wireless base station device 101B is a macro base station.

  Radio base station apparatus 101B forms macro cell MCB having a radius of several kilometers, for example. The radio base station apparatuses 101A, 101C, 101D, and 101E form femtocells FCA, FCC, FCD, and FCE having a radius of several tens of meters, for example.

  Here, a state is considered in which a plurality of femto base stations exist in a macro cell formed by the macro base station 101B.

  The radio base station apparatus 101B can communicate with the radio terminal apparatus 202 by transmitting and receiving radio signals to and from the radio terminal apparatus 202 existing in the macro cell MCB.

  The radio base station apparatuses 101A, 101C, 101D, and 101E are installed in places where the radio terminal apparatus 202 is difficult to receive radio signals from the radio base station apparatus 101B, such as in homes and underground malls, respectively. It is possible to communicate with the wireless terminal device 202 by transmitting and receiving wireless signals to and from the wireless terminal device 202 existing in the FCE.

  In FIG. 2, each of the femtocells FCA and FCC formed by the radio base station apparatus 101A and the radio base station apparatus 101C overlap each other. In addition, the femtocells FCA and FCD respectively formed by the radio base station apparatus 101A and the radio base station apparatus 101D are partially overlapped. In addition, a part of each of the femtocells FCA and FCE formed by the radio base station apparatus 101A and the radio base station apparatus 101E overlap each other.

  Currently, there is a wireless terminal device 202 communicating with the wireless base station device 101A, and this wireless terminal device 202 is an overlapping part of the femtocells FCA, FCC, FCD formed by the wireless base station devices 101A, 101C, 101D, respectively. Is located. In addition, one of the radio base station apparatuses 101A and 101E is located in a cell formed by the other.

  In the radio communication system according to the first embodiment of the present invention, radio base station apparatuses 101A, 101B, 101C, 101D, and 101E each operate as an adjacent cell processing apparatus. That is, each of the radio base station apparatuses 101A, 101B, 101C, 101D, and 101E optimizes neighboring cell information by itself.

  Hereinafter, each of the radio base station apparatuses 101A, 101B, 101C, 101D, and 101E may be referred to as a radio base station apparatus 101. Further, in FIG. 2, one macro base station and four femto base stations are representatively shown, but a small number or even more macro base stations and femto base stations may be provided.

FIG. 3 is a diagram illustrating the configuration of the radio base station apparatus according to the first embodiment of the present invention.
Referring to FIG. 3, radio base station apparatus 101 includes an antenna 91, a circulator 92, a radio reception unit 93, a radio transmission unit 94, and a signal processing unit 95. The signal processing unit 95 includes a reception signal processing unit 96 and a transmission signal processing unit 97. The signal processing unit 95 is realized by a CPU (Central Processing Unit) or a DSP (Digital Signal Processor).

  The circulator 92 outputs the radio signal from the radio terminal device 202 received by the antenna 91 to the radio reception unit 93 and outputs the radio signal received from the radio transmission unit 94 to the antenna 91.

  The radio reception unit 93 converts the radio signal received from the circulator 92 into a baseband signal or IF (Intermediate Frequency) signal, converts the frequency-converted signal into a digital signal, and outputs the digital signal to the reception signal processing unit 96.

  The received signal processing unit 96 performs signal processing such as despreading in the CDMA (Code Division Multiple Access) method on the digital signal received from the wireless receiving unit 93, and part or all of the digital signal after this signal processing is performed. It is converted into a predetermined frame format and transmitted to the core network side.

  The transmission signal processing unit 97 performs IFFT (Inverse Fast Fourier Transform) in an OFDM (Orthogonal Frequency Division Multiplex) method on communication data obtained by converting communication data received from the core network side into a predetermined frame format or communication data generated by itself. The digital signal after the signal processing is output to the wireless transmission unit 94.

  The radio transmission unit 94 converts the digital signal received from the transmission signal processing unit 97 into an analog signal, converts the frequency of the converted analog signal into a radio signal, and outputs the radio signal to the circulator 92.

FIG. 4 is a diagram showing a configuration of the signal processing unit according to the first embodiment of the present invention.
Referring to FIG. 4, received signal processing unit 96 includes a measurement information acquisition unit 11 and an adjacent cell information generation unit 12. The transmission signal processing unit 97 includes an adjacent cell information transmission unit 13 and a power measurement instruction unit 14.

  The measurement information acquisition unit 11 acquires measurement information indicating a measurement result of a radio signal transmitted from another radio base station apparatus 101 based on information from at least one of the other radio base station apparatus 101 and the radio terminal apparatus 202. To do.

  The neighboring cell information generation unit 12 is based on the measurement information acquired by the measurement information acquisition unit 11 and is a radio communication system other than a radio base station apparatus (hereinafter also referred to as a target base station) to which neighboring cell information is given. Of the plurality of radio base station devices 101 in 301, neighboring cell information indicating one or more radio base station devices 101 installed around the target base station is generated. In the radio base station apparatus according to the first embodiment of the present invention, the target base station is its own radio base station apparatus 101.

  For example, the neighboring cell information generation unit 12 generates neighboring cell information indicating one or a plurality of radio base station apparatuses 101 that are candidates for a handover destination of the radio terminal apparatus 202 communicating with the target base station.

  The neighboring cell information transmission unit 13 is formed by the wireless terminal device 202 that can communicate the neighboring cell information generated by the neighboring cell information generation unit 12 with its own radio base station device 101, that is, its own radio base station device 101. It transmits to the radio | wireless terminal apparatus 202 which exists in a cell.

  The power measurement instruction unit 14 transmits to the wireless terminal device 202 a measurement start request for causing the wireless terminal device 202 to measure the reception level of the wireless signal transmitted from the other wireless base station device 101.

[Operation]
Next, the operation when the radio base station apparatus according to the first embodiment of the present invention generates neighboring cell information will be described.

  FIG. 5 is a diagram illustrating an example of a sequence in which the wireless base station device generates initial neighboring cell information in the wireless communication system according to the first embodiment of the present invention.

  In a state where the radio base station apparatus 101 does not have neighboring cell information, such as when the radio base station apparatus 101 is activated, the radio base station apparatus 101 instructs the radio terminal apparatus 202 to search for all frequencies. For example, in LTE, when the radio terminal apparatus 202 first establishes an RRC (Radio Resource Control) connection with the radio base station apparatus 101, that is, when processing for starting communication with the radio base station apparatus 101 is completed, The radio base station apparatus 101 instructs the radio terminal apparatus 202 to search for all frequencies.

  Here, the all frequency search means that the reception level of the radio signal from each radio base station apparatus 101 is measured for all types of transmission frequencies set in the radio communication system.

  Then, the radio base station apparatus 101 generates neighboring cell information based on the measurement result report from the radio terminal apparatus 202 and stores it in a storage unit (not shown).

  More specifically, referring to FIG. 5, first, radio base station apparatus 101A sets another radio base station apparatus to be measured by radio terminal apparatus 202 (step S101).

  Next, the wireless base station device 101A transmits to the wireless terminal device 202 a measurement start request for causing the wireless terminal device 202 to measure the reception level of the wireless signal transmitted from the set other wireless base station device. This measurement start request includes information about the frequency to be measured and the radio base station apparatus (step S102).

  Next, the wireless terminal device 202 receives the measurement start request from the wireless base station device 101A, and measures the reception level of the wireless signal transmitted from the wireless base station device indicated by the received measurement start request (step S103). .

  Next, the wireless terminal device 202 transmits a measurement result notification indicating the measurement result of the reception level to the wireless base station device 101A (step S104).

  Next, the wireless base station device 101A generates initial neighboring cell information based on the measurement result notification received from the wireless terminal device 202 (step S105).

  Note that the radio base station apparatus 101A may instruct the radio terminal apparatus 202 that first establishes the RRC connection not only at the time of activation but to search for all frequencies for every fixed period.

  In addition, when the radio base station apparatus 101A is a femto base station and operates in the hybrid mode, the radio base station apparatus 101A, for example, when the non-member radio terminal apparatus 202 establishes an RRC connection, The terminal device 202 is instructed to search all frequencies.

  That is, when the target base station operates in the hybrid mode, the power measurement instruction unit 14 transmits a radio signal transmitted from the radio base station apparatus 101 other than the target base station to the radio terminal apparatus 202 that is not registered. It is instructed to measure the reception level at all frequencies.

With such a configuration, it is possible to prevent the power consumption of the wireless terminal device 202 owned by the registered user from being consumed, so that an appropriate communication service can be provided.

  Alternatively, when the target base station operates in the hybrid mode, the power measurement instruction unit 14 transmits the radio signal transmitted from the radio base station apparatus 101 other than the target base station to the registered radio terminal apparatus 202. The configuration may be such that the reception level is measured at all frequencies.

  With such a configuration, it is possible to prevent the power consumption of the wireless terminal device 202 owned by a non-registered user who often does not have an environment capable of charging the wireless terminal device 202 immediately. Communication services can be provided.

  FIG. 6 is a diagram illustrating an example of a sequence in which the wireless base station device acquires measurement information in the wireless communication system according to the first embodiment of the present invention.

  Referring to FIG. 6, first, radio base station apparatus 101A transmits a frequency to be measured by radio terminal apparatus 202 that is communicating with itself, and another radio base station apparatus that transmits a measurement cell, that is, a radio signal of the frequency. Are set (step S111).

  Next, the wireless base station device 101A transmits to the wireless terminal device 202 a measurement start request for causing the wireless terminal device 202 to measure the reception level of the wireless signal transmitted from the set other wireless base station device. This measurement start request includes information of the radio base station apparatus 101 to be measured, that is, a cell ID. This information is, for example, neighboring cell information generated by the sequence shown in FIG. Further, the measurement start request includes the transmission frequency of each radio base station apparatus 101 (step S112).

  Next, radio terminal apparatus 202 receives the measurement start request from radio base station apparatus 101A, and receives a radio signal transmitted from the radio base station apparatus indicated by the measurement start request at the frequency indicated by the received measurement start request. The level is measured (step S113).

  Next, the wireless terminal device 202 transmits a measurement result notification indicating the measurement result of the reception level to the wireless base station device 101A. For example, the wireless terminal device 202 periodically measures the reception level, and when the communication state with the wireless base station device 101A deteriorates, and with the wireless base station device 101 other than the wireless base station device 101A When the communication state is improved, a measurement result notification is transmitted to the radio base station apparatus 101A (step S114).

  Next, 101 A of radio base station apparatuses acquire the measurement information which shows the measurement result for every cell ID based on the measurement result notification received from the radio | wireless terminal apparatus 202, and preserve | save it in the memory | storage part which is not shown in figure (step S115).

  In addition, when the radio terminal apparatus 202 detects a cell not notified from the radio base station apparatus 101, the radio terminal apparatus 202 may report the detected cell measurement result to the radio base station apparatus 101.

  In addition, the radio base station apparatus 101 may cause the radio terminal apparatus 202 to perform detection of neighboring cells and power measurement at all frequencies by instructing measurement for all frequencies available in the radio communication system 301. Is possible.

  FIG. 7 is a diagram showing an exemplary sequence of a handover operation in the wireless communication system according to the first embodiment of the present invention.

  Referring to FIG. 7, the operations in steps S81 to S85 are the same as steps S111 to S115 in the sequence shown in FIG.

  Next, based on the measurement result notification received from the wireless terminal device 202, the wireless base station device 101A determines whether or not the wireless terminal device 202 should be handed over. For example, radio base station apparatus 101B is determined as a handover destination with reference to the information, and a handover request indicating radio base station apparatus 101B is transmitted to the host apparatus (step S86).

  Here, in the radio communication system according to the first embodiment of the present invention, handover means that radio base station apparatus 101 that is a communication partner of radio terminal apparatus 202 during a call or data communication is switched. To do.

  Next, the higher-level apparatus receives the handover request from the radio base station apparatus 101A and transmits the handover request to the radio base station apparatus 101B (step S87).

  Next, the radio base station apparatus 101B receives the handover request from the higher-level apparatus and transmits a handover response to the handover request to the higher-level apparatus (Step S88).

  Next, the higher-level device receives a handover response from the radio base station device 101B and transmits a handover instruction to the radio base station device 101A (step S89).

  Next, the radio base station apparatus 101A receives a handover instruction from the higher-level apparatus and transmits an RRC connection re-establishment instruction to the radio terminal apparatus 202 (step S90).

  Next, the wireless base station device 101A transmits a state notification indicating its own communication state and the like to the higher-level device (step S91).

  Next, the higher-level device receives the status notification from the radio base station device 101A, and transmits a status notification indicating communication contents and the like with the radio terminal device 202 to the radio base station device 101B (step S92).

  When the RRC connection is established between the wireless terminal device 202 and the wireless base station device 101B, the wireless terminal device 202 transmits an RRC connection establishment notification to the wireless base station device 101B (step S93).

  Next, the wireless base station device 101B receives the RRC connection establishment notification from the wireless terminal device 202 and transmits a handover completion notification to the higher-level device (step S94).

  Next, the higher-level apparatus receives a handover completion notification from the radio base station apparatus 101B, and transmits a terminal information release instruction to the radio base station apparatus 101A (step S95).

  Next, the wireless base station device 101A receives a terminal information release instruction from the higher-level device, releases information related to the wireless terminal device 202, and transmits a terminal information release completion notification to the higher-level device (step S96).

  Next, a method for updating neighboring cell information generated by the sequence shown in FIG. 5 will be described.

  The radio base station apparatus 101 ranks the list of radio base station apparatuses saved in a storage unit (not shown) using an index. That is, the neighboring cell information generation unit 12 is arranged around the target base station among the plurality of radio base station devices 101 other than the target base station based on the measurement information acquired by the measurement information acquisition unit 11. Alternatively, neighboring cell information in which a plurality of radio base station apparatuses 101 are ranked is generated.

  FIG. 8 is a diagram illustrating an example of a cell ID and a carrier frequency of each radio base station apparatus in the radio communication system illustrated in FIG.

  Referring to FIG. 8, the cell ID of radio base station apparatus 101A is 1111 and the carrier frequency of the radio signal transmitted from radio base station apparatus 101A is f1. The cell ID of the radio base station apparatus 101B is 2222, and the carrier frequency of the radio signal transmitted from the radio base station apparatus 101B is f1. The cell ID of the radio base station apparatus 101C is 3333, and the carrier frequency of the radio signal transmitted from the radio base station apparatus 101C is f1. The cell ID of the radio base station apparatus 101D is 4444, and the carrier frequency of the radio signal transmitted from the radio base station apparatus 101D is f2. The cell ID of the radio base station apparatus 101E is 5555, and the carrier frequency of the radio signal transmitted from the radio base station apparatus 101E is f2.

  In this case, for example, the radio base station apparatus 101A measures the radio signal transmitted from the radio base station apparatuses 101A, 101B, and 101C at the frequency f1 with reference to the initial neighboring cell information generated by the sequence shown in FIG. And instructs the wireless terminal device 202 to measure the wireless signal transmitted from the wireless base station device 101D at the frequency f2.

  Then, the radio terminal apparatus 202 reports the measurement result to the radio base station apparatus 101A according to the sequence shown in FIG. 6, that is, transmits a measurement result notification to the radio base station apparatus 101A.

FIG. 9 is a diagram illustrating an example of measurement information acquired by the wireless base station device.
Referring to FIG. 9, radio base station apparatus 101A has a reception level of a radio signal transmitted from radio base station apparatus 101A whose cell ID is 1111 based on the measurement result notification transmitted from radio terminal apparatus 202. 10, the reception level of the radio signal transmitted from the radio base station apparatus 101B with the cell ID 2222 is 8, and the reception level of the radio signal transmitted from the radio base station apparatus 101C with the cell ID 3333 is 3 and measurement information indicating that the reception level of the radio signal transmitted from the radio base station apparatus 101D having the cell ID 4444 is 4 is obtained.

FIG. 10 is a diagram illustrating an example of neighboring cell information generated by the wireless base station device.
Referring to FIG. 10, from the measurement information shown in FIG. 9 acquired by radio base station apparatus 101A, the magnitude of the reception level is in the order of radio base station apparatus 101B, radio base station apparatus 101D, and radio base station apparatus 101C. . Therefore, the radio base station apparatus 101A registers the radio base station apparatuses 101B, 101D, and 101C in the adjacent cell information in this order. That is, the radio base station apparatus 101A has the initial neighboring cell information generated by the sequence shown in FIG. 5, the reception level at the frequency f1 is 8, the cell ID 2222 (radio base station apparatus 101B) is first, and the frequency f2 An adjacent cell indicating that the reception level at 4 is cell ID 4444 (radio base station apparatus 101D) is second, the reception level at frequency f1 is 3, and cell ID 3333 (radio base station apparatus 101C) is third. Update to information.

  Then, when the adjacent cell information is updated, for example, the wireless base station device 101A notifies the updated wireless terminal device 202 of the updated adjacent cell information. Here, 101 A of radio base station apparatuses alert | report to the radio | wireless terminal apparatus 202 by making N pieces (N is an integer greater than or equal to 1) from the top among the ranked radio base station apparatuses, for example.

  Specifically, when the number of wireless base station devices that can be registered in the neighboring cell information notified to the wireless terminal device 202 is limited to two, the wireless base station device 101A has a cell ID 2222 (wireless base station device 101B). Is the first place, and neighboring cell information indicating that the cell ID 4444 (wireless base station apparatus 101D) is second place is notified to each wireless terminal apparatus 202.

FIG. 11 is a diagram illustrating another example of neighboring cell information generated by the wireless base station device.
In the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 has a plurality of other than the target radio base station apparatus 101 based on the measurement information acquired by the measurement information acquisition unit 11. Although the wireless base station apparatus 101 is ranked and the neighboring cell information is generated based on the ranking result, the present invention is not limited to this.

  The neighboring cell information generation unit 12 does not perform ranking according to the magnitude of the reception level, and based on the measurement information acquired by the measurement information acquisition unit 11, from among the plurality of radio base station devices 101 other than the target base station, The structure which determines the wireless base station apparatus 101 which is not registered into adjacent cell information may be sufficient. For example, the neighboring cell information generation unit 12 generates neighboring cell information excluding at least the radio base station apparatus 101 whose reception level is less than a predetermined threshold.

  Referring to FIG. 11, for example, when the threshold is 4, neighboring cell information generation unit 12 registers radio base station devices 101B and 101D in the neighboring cell information except for radio base station device 101C. Then, the neighboring cell information transmission unit 13 notifies the wireless terminal device 202 of the neighboring cell information.

[Notification of neighboring cell information]
As described above, the radio base station apparatus 101 optimizes neighboring cell information with the acquisition of measurement information. The optimized neighboring cell information needs to be notified to the wireless terminal device 202. That is, the neighboring cell information transmission unit 13 in the radio base station apparatus 101 communicates the neighboring cell information generated by the neighboring cell information generation unit 12 with the own radio base station apparatus 101 that is the target base station. Send to. As the notification method, for example, the following three methods are conceivable.

  FIG. 12 is a diagram illustrating an example of a method in which the wireless base station device notifies neighboring cell information to the wireless terminal device in the wireless communication system according to the first embodiment of the present invention.

  Referring to FIG. 12, radio base station apparatus 101A notifies wireless terminal apparatus 202 in the idle state, that is, in a state where no telephone call or data communication is performed, with neighboring cell information included in broadcast information. In this case, the wireless base station device 101A notifies the wireless terminal device 202 that the neighboring cell information has been updated using the notification information change notification.

  More specifically, when optimization of neighboring cell information occurs (step S27), the radio base station apparatus 101A broadcasts a notification information change notification to each radio terminal apparatus 202 existing in the femtocell FCA (step S28).

  Next, 101 A of radio base station apparatuses broadcast the alerting | reporting information containing the updated adjacent cell information to each radio | wireless terminal apparatus 202 which exists in femtocell FCA. And the radio | wireless terminal apparatus 202 which received notification information change notification reads neighboring cell information from the alerting | reporting information transmitted from 101 A of radio base station apparatuses, and updates the neighbor cell information which self hold | maintains to the read neighboring cell information (Step S29).

  Next, the wireless terminal device 202 receives a measurement start request autonomously or from the wireless base station device 101A, and measures the reception level of the wireless signal transmitted from the wireless base station device 101 indicated by the updated neighboring cell information (Step S30).

  FIG. 13 is a diagram illustrating an example of a method in which the wireless base station device notifies neighboring cell information to the wireless terminal device in the wireless communication system according to the first embodiment of the present invention.

  Referring to FIG. 13, for example, in LTE, radio base station apparatus 101 </ b> A notifies neighboring cell information to radio terminal apparatus 202 that performs an RRC connection establishment process when setting up a radio data link.

  More specifically, first, various control processes in the previous stage of transmitting / receiving communication data such as a link setting of a radio control signal, that is, an IP (Internet Protocol) packet, are performed between the radio terminal apparatus 202 and the radio base station apparatus 101A ( Step S31).

  Next, NAS (Non-Access Stratum) layer security processing, that is, transmission / reception of information necessary for communication encryption is performed between the wireless terminal device 202 and the wireless base station device 101A (step S32). For example, in LTE, the wireless terminal device 202 exchanges the information with a host device in the core network, and the wireless base station device 101A plays a role of relaying the information.

  Next, a wireless data link is set between the wireless terminal device 202 and the wireless base station device 101A, and thereafter communication data such as IP packets is transmitted and received between the wireless terminal device 202 and the wireless base station device 101A. Also, the radio base station apparatus 101A transmits to the radio terminal apparatus 202 a measurement start request for causing the radio terminal apparatus 202 to measure the reception level of the radio signal transmitted from the other radio base station apparatus 101 (step S33). . For example, in LTE, the measurement start request is included in the wireless data link setting request notified from the wireless base station device 101A to the wireless terminal device 202. The measurement start request includes neighboring cell information.

  Next, the wireless terminal device 202 receives the measurement start request from the wireless base station device 101A, updates the neighboring cell information held by itself to the newly notified neighboring cell information, and updates the updated neighboring cell information. The reception level of the radio signal transmitted from the radio base station apparatus 101 indicated by is measured (step S34).

  FIG. 14 is a diagram illustrating an example of a method in which a radio base station device notifies neighboring cell information to a radio terminal device in the radio communication system according to the first embodiment of the present invention.

  Referring to FIG. 14, wireless base station apparatus 101A notifies wireless terminal apparatus 202 in communication with itself of the update of neighboring cell information using a measurement change request.

  More specifically, when optimization of neighboring cell information occurs (step S27), the wireless base station device 101A includes the updated neighboring cell information in a measurement change request and transmits the measurement change request to the wireless terminal device 202 (step S41). .

  Next, the wireless terminal device 202 changes the neighboring cell information held by itself to the neighboring cell information included in the measurement change request received from the wireless base station device 101A, and the wireless base station indicated by the changed neighboring cell information The reception level of the radio signal transmitted from the apparatus 101 is measured (step S42).

  By the way, the purchaser of the femto base station can uniquely determine the installation location of the femto base station. For this reason, in a radio communication system in which a femto base station is installed, the femto base station is likely to move and the power is turned on / off. Therefore, appropriate neighboring cell information in the radio base station apparatus in which the femto base station exists in the vicinity. It becomes difficult to generate.

  For example, the wireless terminal device measures the received power from the femto base station registered in the neighboring cell information autonomously or in accordance with an instruction from the femto base station using the neighboring cell information, and uses the measurement result. Report to femto base station. In this case, if a femto base station that is not suitable as a handover destination is registered in the neighboring cell information, the wireless terminal device performs a useless measurement operation, and a useless handover occurs.

  On the other hand, in the radio communication system according to the first embodiment of the present invention, the measurement information acquisition unit 11 displays the measurement results of radio signals transmitted from a plurality of radio base station apparatuses 101 other than the target base station. Measurement information to be shown is acquired based on information from the wireless terminal device 202, that is, measurement result notification. Based on the measurement information acquired by the measurement information acquisition unit 11, the neighboring cell information generation unit 12 is arranged around the target base station among the plurality of radio base station devices 101 other than the target radio base station device 101. Also, neighboring cell information indicating one or a plurality of radio base station apparatuses 101 is generated.

  With such a configuration, the neighboring cell information can be automatically optimized regardless of the movement of the femto base station and the power on / off. Therefore, the operation of the wireless communication system 301 can be performed without human intervention. Efficiency can be improved. In addition, since the neighboring cell information is automatically optimized, a special installation process for the radio base station apparatus 101 is not required, so that the work time and cost for installing the radio base station apparatus 101 can be reduced. Can be planned.

  Further, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 is based on the measurement information acquired by the measurement information acquisition unit 11 and a plurality of radio bases other than the target base station. The station apparatus 101 is ranked, and neighboring cell information based on the ranking result is generated.

  With such a configuration, it is possible to generate detailed neighboring cell information and further improve the efficiency of the operation in the radio communication system. For example, the radio base station apparatus 101 can increase the success rate of handover by preferentially selecting an upper radio base station apparatus as a handover destination in the ranking result.

  Moreover, in the radio | wireless communications system which concerns on the 1st Embodiment of this invention, the adjacent cell information production | generation part 12 is N (N is an integer greater than or equal to 1) from the top among the several radio base station apparatuses 101 ranked. The neighboring cell information indicating the wireless base station device is generated.

  With such a configuration, for example, when there is a limit on the number of radio base station apparatuses that can be included in the neighboring cell information notified to the radio terminal apparatus 202, the top N radio base station apparatuses are included in the neighboring cell information. Thus, it is possible to notify the wireless terminal device 202 of appropriate neighboring cell information.

  Further, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 generates neighboring cell information that further indicates the ranking of the ranked radio base station apparatus 101.

  With such a configuration, it is possible to generate more detailed neighboring cell information and further improve the efficiency of the operation in the radio communication system. For example, the radio terminal apparatus 202 can perform an efficient measurement operation by determining the measurement order and narrowing down the radio base station apparatuses to be measured according to the rank of the radio base station apparatus in the neighboring cell information.

  In the radio communication system according to the first embodiment of the present invention, the measurement information acquisition unit 11 receives reception levels of radio signals transmitted from a plurality of radio base station apparatuses 101 other than the target radio base station apparatus 101. Is obtained based on the information from the wireless terminal device 202.

  Thus, appropriate neighboring cell information can be generated by including which radio base station device is included in the neighboring cell information and using the reception level as a criterion for ranking the radio base station devices.

  Moreover, in the radio | wireless communications system which concerns on the 1st Embodiment of this invention, the adjacent cell information production | generation part 12 of the radio base station apparatus 101 with a large reception level which measurement information shows in the ranking of the radio base station apparatus 101 The rank is higher than that of the radio base station apparatus 101 having a low reception level.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses 101 according to the actually measured reception level.

  Further, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 has a predetermined reception level indicated by the measurement information from among a plurality of radio base station apparatuses 101 other than the target base station. Neighbor cell information excluding at least the radio base station apparatus 101 that is less than the value is generated.

  With such a configuration, it is possible to appropriately delete the radio base station apparatus 101 having a low actually measured reception level from the neighboring cell information.

  In addition, at least one of the plurality of radio base station apparatuses 101 in the radio communication system according to the first embodiment of the present invention is a femto base station.

  As described above, by generating appropriate neighboring cell information in a wireless communication system in which movement of the wireless base station device and power on / off frequently occur, the effect of improving the operation efficiency in the wireless communication system is more remarkable. Can get to.

  Further, when the femto base station is automatically set using the technique described in Patent Document 1, all of the neighboring femto base stations are treated as neighboring cells and registered in neighboring cell information, which is a candidate for a handover destination. For this reason, there is a possibility that a femto base station that is not originally suitable for a handover destination may be registered in the neighboring cell information, such as a femto base station existing on the other side of the wall with respect to the wireless terminal device.

  On the other hand, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 uses a plurality of information other than the target base station based on the measurement information acquired by the measurement information acquisition unit 11. Neighbor cell information indicating one or a plurality of radio base station apparatuses 101 that are candidates for handover of the radio terminal apparatus 202 communicating with the target base station is generated.

  With such a configuration, it is possible to optimize the handover operation in the femtocell of the installed radio base station apparatus 101. Further, by optimizing the neighboring cell information, the number of neighboring cells that are handover destination candidates for the wireless terminal device 202 in communication can be reduced, so that it is possible to prevent unnecessary handover from occurring. .

  Moreover, in the radio | wireless communications system which concerns on the 1st Embodiment of this invention, the adjacent cell information generation part 12 becomes a measuring object of the radio | wireless terminal apparatus 202 among the some radio base station apparatuses 101 other than an object base station. Neighbor cell information indicating one or a plurality of radio base station apparatuses 101 is generated.

  Thus, by optimizing the neighboring cell information, the number of neighboring cells to be measured by the wireless terminal device 202 can be reduced, so that the wireless terminal device 202 performs a useless measurement operation. Can be prevented.

  Further, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 uses the radio terminal device 202 of the plurality of radio base station devices 101 other than the target base station to measure the reception level. Next, neighboring cell information indicating one or a plurality of radio base station apparatuses 101 that transmit radio signals to be transmitted is generated.

  As described above, by optimizing the neighboring cell information, the number of neighboring cells for which the wireless terminal device 202 performs reception level measurement can be reduced, so that the wireless terminal device 202 performs a useless measurement operation. Can be prevented.

  Moreover, in the radio | wireless communications system which concerns on the 1st Embodiment of this invention, the adjacent cell information production | generation part 12 is idle, ie, is communicating with a target base station among several radio base station apparatuses 101 other than a target base station. The non-radio wireless terminal apparatus 202 generates neighboring cell information indicating one or a plurality of wireless base station apparatuses 101 that transmit a wireless signal whose reception level is to be measured.

  With such a configuration, the number of neighboring cells that are the targets of periodic power measurement indicated by broadcast information or the like from the radio base station apparatus 101 can be reduced. Can be prevented. In particular, since the power consumption of the wireless terminal device 202 in the idle state can be reduced, a remarkable effect can be obtained.

  Further, in the radio communication system according to the first embodiment of the present invention, the neighboring cell information generation unit 12 transmits the radio terminal apparatus 202 communicating with the target base station from the radio base station apparatus 101 other than the target base station. The initial information of the neighboring cell information is generated based on the result of measuring the reception level of the radio signal for all frequencies.

  With such a configuration, it is possible to construct appropriate neighboring cell information at an early stage, and it is possible to realize an efficient operation in the wireless communication system 301 at an early stage.

  In the radio communication system according to the first embodiment of the present invention, radio base station apparatus 101 optimizes neighboring cell information by itself. That is, the neighboring cell processing apparatus according to the first embodiment of the present invention is included in the radio base station apparatus 101.

  With such a configuration, for example, it is not necessary to perform optimization of neighboring cell information of each radio base station apparatus 101 in a host apparatus in the core network, and the processing load in the radio communication system 301 can be distributed. The amount of communication between devices can be reduced.

  In the radio communication system according to the first embodiment of the present invention, the radio base station apparatus 101 is configured to cause the radio terminal apparatus 202 to measure received power, but the present invention is not limited to this. When the radio base station apparatus 101 itself can measure the received power of the radio signal from the other radio base station apparatus 101, the radio base station apparatus 101 itself measures the reception power by measuring the received power. May be obtained.

  In the radio communication system according to the first embodiment of the present invention, the reception level of the radio signal transmitted from the radio base station apparatus 101 is used as an index for determining the ranking of the radio base station apparatus as it is. However, the present invention is not limited to this. For example, an SNR (Signal to Noise Ratio) is calculated from the reception level of a radio signal transmitted from a certain radio base station apparatus 101 and the reception level of a radio signal transmitted from another radio base station apparatus 101 serving as an interference source. The SNR may be used as an index for determining the ranking of the radio base station apparatus. Further, a configuration may be used in which CINR (carrier to interference and noise ratio) is used as an index for determining the ranking of the radio base station apparatus instead of SNR.

  Further, in the radio base station apparatus according to the first embodiment of the present invention, the neighboring cell information generation unit 12 is configured so that the radio terminal apparatus 202 communicating with the target base station is from the radio base station apparatus 101 other than the target base station. Although the configuration is such that the initial information of the neighboring cell information is generated based on the result of measuring the reception level of the transmitted radio signal for all frequencies, the present invention is not limited to this. The configuration is not limited to measuring all types of transmission frequencies of the radio base station apparatus 101 in the radio communication system, and may be configured to measure a plurality of frequencies that are a part of them.

  Further, the radio communication system according to the first embodiment of the present invention has a configuration in which the radio base station apparatus 101 serving as a communication partner of the radio terminal apparatus 202 is switched by the radio base station apparatus 101 as a handover operation. However, the present invention is not limited to this. The wireless base station device 101 that is a communication partner of the wireless terminal device 202 may be configured to be switched by the wireless terminal device 202.

  In the first embodiment of the present invention, the handover operation of the radio terminal apparatus has been specifically described. However, inter-base station movement (inter-cell movement) performed by the radio terminal apparatus communicating with the radio base station apparatus. The present invention is applied not only to handover as an operation but also to movement between base stations (movement between cells) performed by an idle wireless terminal device. That is, in the first embodiment of the present invention, the present invention is also applied to a configuration and operation in which “handover” is replaced with “movement”.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Second Embodiment>
The present embodiment relates to a wireless communication system in which the content of measurement information is changed as compared with the wireless communication system according to the first embodiment. The contents other than those described below are the same as those of the wireless communication system according to the first embodiment.

In the radio communication system according to the second embodiment of the present invention, the measurement information acquisition unit 11 is a radio terminal based on radio signals transmitted from a plurality of radio base station apparatuses 101 other than the target radio base station apparatus 101. Measurement information indicating the number of times the device 202 detects the presence of the wireless base station device 101 and the detection rate at which the wireless terminal device 202 detects the presence of the wireless base station device 101 is acquired based on information from the wireless terminal device 202 To do. Here, the detection rate is the ratio of the number of times the wireless terminal device 202 detects the presence of the wireless base station device 101 to the number of times the wireless terminal device 202 has performed the measurement.
FIG. 15 is a diagram illustrating an example of a measurement result by the wireless terminal device 202.

  For example, the wireless base station device 101A instructs the wireless terminal device 202 in communication with itself four times to search for all frequencies, and from the measurement result notification by the four times of all frequency searches performed in the wireless terminal device 202, A measurement result as shown in FIG. 15 is acquired.

  That is, the wireless terminal device 202 detects the wireless base station devices 101B, 101C, and 101D in the first measurement, and the wireless terminal device 202 detects the wireless base station devices 101B, 101C, and 101D in the second measurement. , 101E, the wireless terminal device 202 detects the wireless base station devices 101B and 101D in the third measurement, and the measurement result indicating that the wireless terminal device 202 detects the wireless base station device 101B in the fourth measurement The notification is transmitted to the radio base station apparatus 101A.

FIG. 16 is a diagram illustrating an example of measurement information acquired by the wireless base station device.
Referring to FIG. 16, in radio base station apparatus 101A, based on the measurement result notification transmitted from radio terminal apparatus 202, the number of detections by radio base station apparatus 101B is 4, and the detection rate of radio base station apparatus 101B Is 1.00, the detection count of the radio base station apparatus 101C is 2, the detection rate of the radio base station apparatus 101C is 0.50, the detection count of the radio base station apparatus 101D is 3, Measurement information indicating that the detection rate of the station apparatus 101D is 0.75, the number of detections of the radio base station apparatus 101E is 1, and the detection rate of the radio base station apparatus 101E is 0.25 is obtained. .

FIG. 17 is a diagram illustrating an example of neighboring cell information generated by the wireless base station device.
Referring to FIG. 17, from the measurement information acquired by radio base station apparatus 101A, the number of detections and the detection rate are as follows: radio base station apparatus 101B, radio base station apparatus 101D, radio base station apparatus 101C, radio base station It becomes the order of the apparatus 101E. Therefore, the radio base station apparatus 101A registers the radio base station apparatuses 101B, 101D, 101C, and 101E in the adjacent cell information in this order. That is, the radio base station apparatus 101A uses the cell ID 2222 (radio base station apparatus 101B) as the initial neighboring cell information generated by the sequence shown in FIG. 5 with the number of detections at the frequency f1 being 4 and the detection rate being 1.00. Is the first place, the number of detections at the frequency f2 is 3, the detection rate is 0.75, the cell ID 4444 (radio base station apparatus 101D) is the second place, the number of detections at the frequency f1 is 2, and the detection rate is 0. .50, the cell ID 3333 (radio base station apparatus 101C) is third, the number of detections at the frequency f2 is 1, the detection rate is 0.25, and the cell ID 5555 (radio base station apparatus 101E) is fourth. The neighboring cell information shown is updated.

  Then, when the adjacent cell information is updated, for example, the wireless base station device 101A notifies the updated wireless terminal device 202 of the updated adjacent cell information. Here, 101 A of radio base station apparatuses alert | report to the radio | wireless terminal apparatus 202 by making N pieces (N is an integer greater than or equal to 1) from the top among the ranked radio base station apparatuses, for example.

  Specifically, when the number of wireless base station devices that can be registered in the neighboring cell information notified to the wireless terminal device 202 is limited to two, the wireless base station device 101A has a cell ID 2222 (wireless base station device 101B). Is the first place, and neighboring cell information indicating that the cell ID 4444 (wireless base station apparatus 101D) is second place is notified to each wireless terminal apparatus 202.

FIG. 18 is a diagram illustrating another example of neighboring cell information generated by the wireless base station device.
In the radio communication system according to the second embodiment of the present invention, the neighboring cell information generation unit 12 has a plurality of other than the target radio base station apparatus 101 based on the measurement information acquired by the measurement information acquisition unit 11. Although the wireless base station apparatus 101 is ranked and the neighboring cell information is generated based on the ranking result, the present invention is not limited to this.

  The adjacent cell information generation unit 12 does not perform ranking based on the number of times of detection or the detection rate, and based on the measurement information acquired by the measurement information acquisition unit 11, the plurality of radio base station apparatuses 101 other than the target base station. The structure which determines the radio base station apparatus 101 which is not registered into neighboring cell information from inside may be sufficient. That is, the neighboring cell information generation unit 12 generates neighboring cell information excluding at least the radio base station apparatus 101 whose number of detections or detection rate is less than a predetermined threshold.

  Referring to FIG. 18, for example, when the threshold value for the number of detections is 2, neighboring cell information generation unit 12 registers radio base station apparatuses 101B, 101C, and 101D in the neighboring cell information.

  For example, when the threshold of the detection rate is 0.50, the neighboring cell information generation unit 12 registers the radio base station devices 101B, 101C, and 101D in the neighboring cell information.

  Then, the neighboring cell information transmission unit 13 notifies the wireless terminal device 202 of the neighboring cell information.

  As described above, when all the measurements performed by the wireless terminal device 202 are all frequency searches, the ranking of the neighboring cell information based on the number of detections and the ranking of the neighboring cell information based on the detection rate are the same result. When the frequency to be measured in the measurement performed by the device 202 a plurality of times is different, the ranking of the neighboring cell information based on the number of detections and the ranking of the neighboring cell information based on the detection rate are different.

  As described above, in the radio communication system according to the second embodiment of the present invention, the reception levels of radio signals transmitted from a plurality of radio base station apparatuses 101 other than the target radio base station apparatus 101 are set as radio terminal apparatuses. 202 measures and detects the presence of the radio base station apparatus. Then, the measurement information acquisition unit 11 in the radio base station apparatus 101 acquires measurement information indicating the number of times the radio terminal apparatus 202 detects the presence of another radio base station apparatus 101 based on information from the radio terminal apparatus 202. To do.

  In this way, appropriate neighbor cell information is generated by using which radio base station device is included in the neighbor cell information and using the number of times the radio base station device is detected as a criterion for ranking the radio base station device. be able to.

  Further, the measurement information acquisition unit 11 detects that the wireless terminal device 202 detects the presence of the wireless base station device 101 based on wireless signals transmitted from a plurality of wireless base station devices 101 other than the target wireless base station device 101. Measurement information indicating the rate is acquired based on information from the wireless terminal device 202.

  In this way, by generating which neighbor cell information is included in the neighbor cell information and using the detection rate of the radio base station device as a criterion for determining the ranking of the radio base station device, appropriate neighbor cell information is generated Can do.

  Then, the radio base station apparatus 101 ranks the radio base station apparatuses based on the detection rate of the radio base station apparatus measured by the radio terminal apparatus 202, that is, the number of detections / the number of all frequency searches, or the number of detections.

  With such a configuration, it is possible to recognize a radio base station apparatus that is powered on and a radio base station apparatus that is powered off, and generate appropriate neighboring cell information.

  Therefore, in the radio communication system according to the second embodiment of the present invention, it is possible to improve the efficiency of operation in the radio communication system by generating appropriate neighboring cell information.

  Further, in the radio communication system according to the second embodiment of the present invention, the neighboring cell information generation unit 12 has the number of detection times indicated by the measurement information in the ranking of the radio base station apparatus 101. The rank is raised higher than that of the radio base station apparatus 101 having a small number of detections.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses 101 according to the results of actual detection of existence.

  Moreover, in the radio | wireless communications system which concerns on the 2nd Embodiment of this invention, the adjacent cell information production | generation part 12 has predetermined detection frequency which measurement information shows among several radio base station apparatuses 101 other than a object base station. Neighbor cell information excluding at least the radio base station apparatus 101 that is less than the value is generated.

  With such a configuration, it is possible to appropriately delete the radio base station apparatus 101 that is actually detected and has a small track record from the neighboring cell information.

  Further, in the radio communication system according to the second embodiment of the present invention, the neighboring cell information generation unit 12 has the radio base station apparatus 101 having a large detection rate indicated by the measurement information in the ranking of the radio base station apparatus 101. The rank is higher than that of the radio base station apparatus 101 having a small detection rate.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses 101 according to the results of actual detection of existence.

  Moreover, in the radio | wireless communications system which concerns on the 2nd Embodiment of this invention, the adjacent cell information production | generation part 12 has the detection rate which measurement information shows predetermined among several radio base station apparatuses 101 other than a object base station. Neighbor cell information excluding at least the radio base station apparatus 101 that is less than the value is generated.

  With such a configuration, it is possible to appropriately delete the radio base station apparatus 101 that is actually detected and has a small track record from the neighboring cell information.

  In the wireless communication system according to the second embodiment of the present invention, the neighboring cell information generation unit 12 is configured to generate neighboring cell information based on the number of detections and the detection rate. Not what you want. The adjacent cell information generation part 12 should just be the structure which produces | generates adjacent cell information based on at least one of the frequency | count of detection and a detection rate.

  Moreover, in the radio | wireless communications system which concerns on the 2nd Embodiment of this invention, although it was set as the structure which the radio | wireless terminal apparatus 202 detects the radio base station apparatus 101, it is not limited to this. When the radio base station apparatus 101 itself can detect another radio base station apparatus 101, the radio base station apparatus 101 itself acquires measurement information by detecting and measuring the radio base station apparatus. May be.

  Further, the measurement information acquisition unit 11 acquires measurement information indicating a measurement result in a certain period past from the present, that is, the radio base station apparatus 101 uses the neighboring cell information based on the measurement history in the certain period past from the present. May be generated.

  For example, the radio base station apparatus 101 may generate neighboring cell information based on a measurement history in a period from the current time to one day ago. Also, the radio base station apparatus 101 may generate neighboring cell information based on a predetermined number of measurement histories. For example, the radio base station apparatus 101 may generate neighboring cell information based on the past 30 latest measurement histories. With such a configuration, for example, it is possible to prevent the rank of the radio base station apparatus 101 whose power is turned off from being kept high forever.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Third Embodiment>
The present embodiment relates to a wireless communication system in which the content of measurement information is changed as compared with the wireless communication system according to the first embodiment. The contents other than those described below are the same as those of the wireless communication system according to the first embodiment.

  In the wireless communication system according to the third embodiment of the present invention, the wireless base station device 101 stores a record of detection of the wireless base station device 101 by itself or the wireless terminal device 202. That is, the measurement information acquisition unit 11 obtains the measurement information indicating the measurement time when the latest measurement result that is the basis for adding or leaving the radio base station apparatus 101 to the neighboring cell information is the information from the radio terminal apparatus 202. Get based on.

  Thereby, the radio base station apparatus 101 can acquire the last update time of the detection record for the radio base station apparatus 101 detected at least once as measurement information. That is, the last update time is the time when the target base station or the radio terminal device 202 can measure the radio base station device 101 other than the target base station, that is, the reception level of the radio signal transmitted from the radio base station device 101 Is a time when is equal to or greater than a predetermined threshold.

  Here, it is considered that the radio base station apparatus 101 having a long elapsed time from the last update time is unlikely to exist in the vicinity at present and is unlikely to be measured. For this reason, the radio base station apparatus 101 ranks the radio base station apparatuses 101 based on the elapsed time from the last update time.

FIG. 19 is a diagram illustrating an example of measurement information acquired by the wireless base station device.
Referring to FIG. 19, in radio base station apparatus 101A, the first measurement is performed at 15:12 on June 14, 2010, and in this first measurement, radio terminal apparatus 202 performs radio base station apparatus 101B. , 101C, 101D are detected, and the second measurement is performed at 23:50 on June 14, 2010, and in this second measurement, the wireless terminal device 202 transmits the wireless base station devices 101B, 101C, 101D, 101E. The third measurement is performed at 6:30 on June 15, 2010, and in this third measurement, the wireless terminal device 202 detects the wireless base station devices 101B and 101D, and the fourth measurement. Was performed at 16:20 on June 15, 2010, and measurement information indicating that the wireless terminal device 202 detected the wireless base station device 101B in the fourth measurement was obtained. There.

FIG. 20 is a diagram illustrating an example of neighboring cell information generated by the wireless base station device.
Referring to FIG. 20, from the measurement information acquired by radio base station apparatus 101A, the last update time at the time when the fourth measurement is completed, that is, the elapsed time from the last detection time, is the radio base station apparatus 101B, radio base station The station device 101D, the radio base station device 101C, and the radio base station device 101E are short in this order. Therefore, the radio base station apparatus 101A registers the radio base station apparatuses 101B, 101D, 101C, and 101E in the adjacent cell information in this order.

  That is, the wireless base station device 101A has the initial detection time of 16:20 on June 15, 2010, and the elapsed time is 0 minute 0 second, for the initial neighboring cell information generated by the sequence shown in FIG. The cell ID 4444 (radio base station apparatus 101D), whose cell ID 2222 (radio base station apparatus 101B) is first, whose last detection time is 6:30 on June 15, 2010 and whose elapsed time is 9 minutes 50 seconds, is cell ID 4444 (radio base station apparatus 101D). Cell ID 3333 (radio base station apparatus 101C), which is in the second place, the last detection time is 23:50 on June 14, 2010, and the elapsed time is 16 minutes 30 seconds, is the third place, and the last detection time is 2010. The cell ID 5555 (radio base station apparatus 101E) whose elapsed time is 16 minutes and 30 seconds at 23:50 on June 14, 2012 is updated to neighboring cell information indicating that it is in fourth place.

  Then, when the adjacent cell information is updated, for example, the wireless base station device 101A notifies the updated wireless terminal device 202 of the updated adjacent cell information. Here, 101 A of radio base station apparatuses alert | report to the radio | wireless terminal apparatus 202 by making N pieces (N is an integer greater than or equal to 1) from the top among the ranked radio base station apparatuses, for example.

  Specifically, when the number of wireless base station devices that can be registered in the neighboring cell information notified to the wireless terminal device 202 is limited to two, the wireless base station device 101A has a cell ID 2222 (wireless base station device 101B). Is the first place, and neighboring cell information indicating that the cell ID 4444 (wireless base station apparatus 101D) is second place is notified to each wireless terminal apparatus 202.

FIG. 21 is a diagram illustrating another example of neighboring cell information generated by the wireless base station device.
In the radio communication system according to the third embodiment of the present invention, the neighboring cell information generation unit 12 has a plurality of other than the target radio base station apparatus 101 based on the measurement information acquired by the measurement information acquisition unit 11. Although the wireless base station apparatus 101 is ranked and the neighboring cell information is generated based on the ranking result, the present invention is not limited to this.

  The adjacent cell information generation unit 12 does not perform ranking according to the length of the elapsed time from the measurement time, and based on the measurement information acquired by the measurement information acquisition unit 11, a plurality of radio base station devices 101 other than the target base station May be configured to determine the radio base station apparatus 101 not registered in the neighboring cell information. That is, the neighboring cell information generation unit 12 generates neighboring cell information excluding at least the radio base station apparatus 101 whose elapsed time from the measurement time is equal to or greater than a predetermined threshold.

  Referring to FIG. 21, for example, when the threshold value of the elapsed time from the last update time is 10 minutes, neighboring cell information generation unit 12 registers radio base station apparatuses 101B and 101D in the neighboring cell information. Then, the neighboring cell information transmission unit 13 notifies the wireless terminal device 202 of the neighboring cell information.

  As described above, in the radio communication system according to the third embodiment of the present invention, the measurement information acquisition unit 11 further includes the latest measurement that is the basis for adding or leaving the radio base station apparatus 101 to the neighboring cell information. Measurement information indicating the measurement time when the result is obtained is acquired based on information from the wireless terminal device 202.

  That is, a radio base station apparatus that is unlikely to exist at the present time by using which radio base station apparatus is included in the neighboring cell information and using the elapsed time from the measurement time as a criterion for ranking the radio base station apparatus And appropriate neighboring cell information can be generated.

  Therefore, in the radio communication system according to the third embodiment of the present invention, it is possible to improve the efficiency of the operation in the radio communication system by generating appropriate neighboring cell information.

  Further, in the radio communication system according to the third embodiment of the present invention, the neighboring cell information generation unit 12 determines the radio base station apparatus 101 having a long elapsed time from the measurement time in the ranking of the radio base station apparatus 101. The rank is lowered as compared with the radio base station apparatus 101 whose elapsed time from the measurement time is short. That is, the radio base station apparatus 101 determines that the existence of a radio base station apparatus that has passed a predetermined time or more from the last update time cannot be guaranteed, and lowers the rank.

  With such a configuration, it is possible to appropriately rank the radio base station apparatuses 101 according to the possibility of existing at the present time.

  Further, in the radio communication system according to the third embodiment of the present invention, the neighboring cell information generation unit 12 has a predetermined elapsed time from the measurement time among the plurality of radio base station apparatuses 101 other than the target base station. Neighbor cell information excluding at least the radio base station apparatus 101 that is equal to or greater than the value is generated. That is, the radio base station apparatus 101 determines that the existence of a radio base station apparatus whose time has elapsed since the last update time cannot be guaranteed, and deletes it from the neighboring cell information.

  With such a configuration, the radio base station apparatus 101 that is unlikely to exist at the present time can be appropriately deleted from the neighboring cell information.

  In the wireless communication system according to the third embodiment of the present invention, the measurement information acquisition unit 11 is configured to acquire a record of the wireless terminal device 202 detecting the wireless base station device 101 as measurement information. However, the present invention is not limited to this. When the radio base station apparatus 101 itself can detect the other radio base station apparatus 101, a record in which the radio base station apparatus 101 itself detects the other radio base station apparatus 101 is acquired as measurement information. It may be a configuration.

  Further, in the wireless communication system according to the first to third embodiments of the present invention, when the wireless base station device 101 finds a new base station, the wireless base station device 101 The new base station may be continuously added to the neighboring cell information until the number of measurements for the station reaches a predetermined value, and this neighboring cell information may be notified to the wireless terminal device 202. In this case, the radio base station apparatus 101 may temporarily increase the number of base stations listed in the neighboring cell information while leaving the radio base station apparatus already listed in the neighboring cell information as it is.

  Also, in the radio communication system according to the first to third embodiments of the present invention, when operating in the hybrid mode, radio base station apparatus 101 assigns weights according to the member / non-member to the reception level. , Detection times, detection rate and elapsed time may be performed. That is, when the target base station operates in the hybrid mode, the neighboring cell information generation unit 12 weights the measurement information of the registered wireless terminal device 202 and the measurement information of the unregistered wireless terminal device 202, and weights them. Based on the result, neighboring cell information is generated.

  With such a configuration, it is possible to generate appropriate neighboring cell information according to the registered wireless terminal device 202 and the unregistered wireless terminal device 202.

  Since other configurations and operations are the same as those of the wireless communication system according to the first embodiment, detailed description thereof will not be repeated here.

  Next, another embodiment of the present invention will be described with reference to the drawings. In the drawings, the same or corresponding parts are denoted by the same reference numerals and description thereof will not be repeated.

<Fourth embodiment>
The present embodiment relates to a wireless communication system in which a gateway device operates as an adjacent cell processing device instead of a wireless base station device as compared with the wireless communication systems according to the first to third embodiments. The contents other than those described below are the same as those of the wireless communication system according to the first to third embodiments.

FIG. 22 is a diagram showing a configuration of a wireless communication system according to the fourth embodiment of the present invention.
Referring to FIG. 22, the wireless communication system 302 includes wireless base station devices 101A, 101B, 101C, 101D, and 101E, a gateway device 203, and a host device 205.

  In the wireless communication system 302, similarly to the wireless communication system 301, the wireless base station devices 101A, 101C, 101D, and 101E are femto base stations, and the wireless base station device 101B is a macro base station.

  Hereinafter, each of the radio base station apparatuses 101A, 101C, 101D, and 101E may be referred to as a femto base station 101. Further, in FIG. 22, one macro base station and four femto base stations are representatively shown, but a larger number of macro base stations and femto base stations may be provided.

  The gateway device 203 performs relay processing of various communication data transmitted between the radio base station devices 101A, 101C, 101D, and 101E and the host device 205 in the core network 204.

FIG. 23 is a diagram illustrating a configuration of a gateway device according to the fourth embodiment of the present invention.
Referring to FIG. 23, gateway device 203 includes base station side transmission / reception unit 81, data processing unit 82, and core network side transmission / reception unit 83.

  The base station side transmitting / receiving unit 81 transmits the communication data received from the data processing unit 82 to each femto base station 101, and outputs the communication data received from each femto base station 101 to the data processing unit 82.

  The data processing unit 82 performs various processes on the communication data received from the base station side transmission / reception unit 81, outputs the processed data to the core network side transmission / reception unit 83, and performs various processing on the communication data received from the core network side transmission / reception unit 83. Processing is performed and output to the base station side transceiver 81.

  The core network side transmission / reception unit 83 outputs the communication data received from the data processing unit 82 to the higher order device 205 in the core network 204, and outputs the communication data received from the higher order device 205 in the core network 204 to the data processing unit 82. To do.

  In the wireless communication system according to the fourth embodiment of the present invention, gateway device 203 optimizes neighboring cell information by monitoring each femto base station under its control.

  FIG. 24 is a diagram illustrating a configuration of a data processing unit in the gateway device according to the fourth embodiment of the present invention.

  Referring to FIG. 24, data processing unit 82 includes measurement information acquisition unit 21, adjacent cell information generation unit 22, and adjacent cell information transmission unit 23.

  The measurement information acquisition unit 21 acquires measurement information indicating a measurement result of a radio signal transmitted from the radio base station apparatus 101 other than the target base station based on information from each femto base station 101.

  Based on the measurement information acquired by the measurement information acquisition unit 21, the adjacent cell information generation unit 22 is installed around the target base station among the plurality of radio base station devices in the radio communication system 302 other than the target base station. In addition, neighboring cell information indicating one or a plurality of radio base station apparatuses is generated.

  The adjacent cell information transmission unit 23 transmits the adjacent cell information generated by the adjacent cell information generation unit 22 to the target base station.

  The content of the neighbor cell information generation method by the neighbor cell information generation unit 22 is the same as the neighbor cell information generation method by the neighbor cell information generation unit 12 according to the first to third embodiments of the present invention, for example.

  FIG. 25 is a diagram illustrating a method in which the gateway device according to the fourth embodiment of the present invention notifies neighboring cell information.

  Referring to FIG. 25, gateway device 203 notifies femto base stations 101A, 101C, 101D, and 101E of corresponding neighboring cell information.

  In addition, although the gateway apparatus according to the fourth embodiment of the present invention is configured to be provided separately from the radio base station apparatus, the present invention is not limited to this. The gateway device 203 may be configured to be included in at least one of the radio base station devices in the radio communication system 302. In this case, the radio base station device on which the gateway device 203 is mounted acquires measurement information based on information from the radio terminal device 202 and other radio base station devices that exist in the cell that the gateway device 203 forms. And the gateway apparatus 203 notifies the produced | generated adjacent cell information to the radio | wireless terminal apparatus 202 which exists in the cell which self forms, and another radio base station apparatus.

  Moreover, in the radio | wireless communications system which concerns on the 1st-4th embodiment of this invention, an adjacent cell information generation part is based on the measurement information acquired by the measurement information acquisition part, and several radio | wireless other than a target base station. Although it was set as the structure which produces | generates the adjacent cell information which shows the 1 or several radio | wireless base station apparatus installed in the periphery of the object base station among base station apparatuses, it is not limited to this. The adjacent cell information generation unit includes handover information indicating the handover operation history of the radio terminal device, and attribute indicating the attribute of the radio base station device, in addition to the measurement information indicating the measurement result of the radio signal transmitted from the radio base station device. The configuration may be such that neighboring cell information is generated based on a combination of information. As the handover information, for example, the number of handovers and the handover success rate can be considered. As attribute information, for example, information on whether the radio base station apparatus is a femto base station or a macro base station can be considered.

  Similarly to the gateway device according to the fourth embodiment of the present invention, in the first to third embodiments of the present invention, the higher-level device 205 is used as the adjacent cell processing device instead of the radio base station device 101. It may be configured to operate.

  Since other configurations and operations are the same as those of the wireless communication system according to the first to fourth embodiments, detailed description thereof will not be repeated here.

  When the radio base station apparatus has a plurality of sectors, that is, when one cell is divided into a plurality of sectors, one sector can be treated as one radio base station apparatus in the neighboring cell information. The present invention may be applied to such a case.

  The above embodiment should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 11 Measurement information acquisition part 12 Adjacent cell information generation part 13 Adjacent cell information transmission part 14 Power measurement instruction | indication part 81 Base station side transmission / reception part 82 Data processing part 83 Core network side transmission / reception part 91 Antenna 92 Circulator 93 Radio | wireless reception part 94 Radio transmission part DESCRIPTION OF SYMBOLS 95 Signal processing part 96 Reception signal processing part 97 Transmission signal processing part 101A, 101B, 101C, 101D, 101E Wireless base station apparatus 202 Wireless terminal apparatus 203 Gateway apparatus 205 Host apparatus 301 Wireless communication system FCA, FCC, FCD, FCE Femtocell MCB Macrocell

Claims (28)

An adjacent cell processing apparatus in a communication system capable of communicating with a plurality of radio base station apparatuses by performing a mobile operation of a radio terminal apparatus,
Measurement information indicating measurement results of radio signals transmitted from a plurality of radio base station apparatuses other than the target radio base station apparatus is acquired based on information from at least one of the radio terminal apparatus and the radio base station apparatus A measurement information acquisition unit for
Based on the measurement information acquired by the measurement information acquisition unit, one or more arranged around the target radio base station apparatus among the plurality of radio base station apparatuses other than the target radio base station apparatus A neighboring cell information generating unit for generating neighboring cell information indicating the wireless base station device of
An adjacent cell information transmission unit for transmitting the adjacent cell information generated by the adjacent cell information generation unit to the target radio base station device or a radio terminal device communicable with the target radio base station device, Cell processing device.   The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and determines the ranking result. The neighboring cell processing apparatus according to claim 1, wherein the neighboring cell information is generated based on the neighboring cell information.   The neighboring cell information generation unit generates neighboring cell information indicating N radio base station devices (N is an integer of 1 or more) from the top among the plurality of ranked radio base station devices. 2. The adjacent cell processing apparatus according to 2.   The neighboring cell processing device according to claim 2 or 3, wherein the neighboring cell information generation unit generates neighboring cell information that further indicates the ranking of the ranked radio base station devices.   The measurement information acquisition unit is a result of at least one of the radio terminal device and the radio base station device measuring reception levels of radio signals transmitted from a plurality of radio base station devices other than the target radio base station device. The adjacent cell processing apparatus according to claim 1, wherein measurement information indicating ??? is acquired based on information from at least one of the radio terminal apparatus and the radio base station apparatus.   The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and in the ranking, The neighboring cell processing apparatus according to claim 5, wherein the rank of the radio base station apparatus having a high reception level indicated by the measurement information is set higher than that of the radio base station apparatus having a low reception level.   The adjacent cell information generation unit excludes at least the radio base station apparatus in which the reception level indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus The neighboring cell processing apparatus according to claim 5, wherein the neighboring cell information is generated.   The measurement information acquisition unit is configured such that at least one of the radio terminal device and the radio base station device is based on radio signals transmitted from a plurality of radio base station devices other than the target radio base station device. The neighboring cell according to any one of claims 1 to 4, wherein measurement information indicating the number of times the presence of a device is detected is acquired based on information from at least one of the wireless terminal device and the wireless base station device. Processing equipment.   The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and in the ranking, The neighboring cell processing apparatus according to claim 8, wherein the rank of the radio base station apparatus with a large number of detections indicated by the measurement information is raised as compared with the radio base station apparatus with a small number of detections.   The adjacent cell information generation unit excludes at least the radio base station apparatus in which the number of detections indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus The neighboring cell processing apparatus according to claim 8, wherein the neighboring cell information is generated.   The measurement information acquisition unit is configured such that at least one of the radio terminal device and the radio base station device is based on radio signals transmitted from a plurality of radio base station devices other than the target radio base station device. The adjacent information according to any one of claims 1 to 4, wherein measurement information indicating a detection rate for detecting the presence of a device is acquired based on information from at least one of the wireless terminal device and the wireless base station device. Cell processing device.   The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and in the ranking, The adjacent cell processing apparatus according to claim 11, wherein the rank of the radio base station apparatus having a large detection rate indicated by the measurement information is increased as compared with the radio base station apparatus having a small detection rate.   The neighboring cell information generation unit excludes at least the radio base station apparatus in which the detection rate indicated by the measurement information is less than a predetermined value from among the plurality of radio base station apparatuses other than the target radio base station apparatus The neighboring cell processing apparatus according to claim 11, wherein the neighboring cell information is generated.   The measurement information acquisition unit obtains measurement information indicating a measurement time at which the latest measurement result obtained from which the radio base station apparatus is added or left in the neighboring cell information is obtained, and the radio terminal apparatus and the radio The adjacent cell processing apparatus according to claim 1, wherein the adjacent cell processing apparatus is acquired based on information from at least one of the base station apparatuses.   The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and in the ranking, The adjacent cell processing apparatus according to claim 14, wherein the rank of the radio base station apparatus having a long elapsed time from the measurement time is lowered as compared with the radio base station apparatus having a short elapsed time from the measurement time.   The neighboring cell information generation unit excludes at least the radio base station apparatus whose elapsed time from the measurement time is a predetermined value or more from among the plurality of radio base station apparatuses other than the target radio base station apparatus The neighboring cell processing apparatus according to claim 14, wherein neighboring cell information is generated.   The adjacent cell processing device according to any one of claims 1 to 16, wherein at least one of the plurality of radio base station devices in the communication system is a femto base station.   The neighboring cell information generation unit is one or more of the plurality of radio base station apparatuses other than the target radio base station apparatus that are candidates for a movement destination of a radio terminal apparatus communicating with the target radio base station apparatus The neighboring cell processing device according to claim 1, wherein neighboring cell information indicating a radio base station device is generated.   The neighboring cell information generating unit is neighboring cell information indicating one or a plurality of the radio base station devices to be measured by the radio terminal device among the plurality of radio base station devices other than the target radio base station device. The adjacent cell processing device according to claim 1, wherein   The adjacent cell information generation unit transmits one or more of the radio base station devices other than the target radio base station device, and the radio terminal device transmits a radio signal whose reception level is to be measured. The neighboring cell processing apparatus according to claim 1, wherein neighboring cell information indicating a radio base station apparatus is generated.   The neighboring cell information generation unit is a target whose reception level is measured by the wireless terminal device that is not communicating with the target wireless base station device among the plurality of wireless base station devices other than the target wireless base station device. The neighboring cell processing apparatus according to claim 20, wherein neighboring cell information indicating one or a plurality of the radio base station apparatuses that transmit radio signals is generated. The adjacent cell information generation unit ranks a plurality of radio base station devices other than the target radio base station device based on the measurement information acquired by the measurement information acquisition unit, and determines the ranking result. Based on neighboring cell information,
The adjacent cell information generation unit is configured such that a radio terminal device communicating with the target radio base station device sets reception levels of radio signals transmitted from the radio base station devices other than the target radio base station device at a plurality of frequencies. The neighboring cell processing apparatus according to any one of claims 1 to 21, wherein initial information of the neighboring cell information is generated based on a measured result. The adjacent cell processing device further includes:
The target radio base station apparatus can register the radio terminal apparatus, and operates in a hybrid mode in which communication is permitted to both the registered radio terminal apparatus and the unregistered radio terminal apparatus When the wireless terminal device is not registered, the reception level of the wireless signal transmitted from the wireless base station device other than the target wireless base station device is measured at the plurality of frequencies. The adjacent cell processing apparatus according to claim 22, further comprising a power measurement instruction unit for instructing. The adjacent cell processing device further includes:
The target radio base station apparatus can register the radio terminal apparatus, and operates in a hybrid mode in which communication is permitted to both the registered radio terminal apparatus and the unregistered radio terminal apparatus If so, instruct the registered radio terminal apparatus to measure the reception level of the radio signal transmitted from the radio base station apparatus other than the target radio base station apparatus at the plurality of frequencies The adjacent cell processing device according to claim 22, further comprising a power measurement instruction unit for performing the operation.   The neighboring cell information generation unit is capable of registering the wireless terminal device by the target wireless base station device, and for both the registered wireless terminal device and the unregistered wireless terminal device. When operating in a hybrid mode that permits communication, the measurement information indicating the measurement result by the registered wireless terminal device and the measurement information indicating the measurement result by the unregistered wireless terminal device are weighted and weighted The adjacent cell processing apparatus according to any one of claims 1 to 24, wherein the adjacent cell information is generated based on a result of the determination.   The adjacent cell processing device according to any one of claims 1 to 25, wherein the measurement information acquisition unit acquires measurement information indicating the measurement result in a certain period from the present to the past.   The neighboring cell processing apparatus according to any one of claims 1 to 26, wherein the neighboring cell processing apparatus is included in one or a plurality of the radio base station apparatuses. An adjacent cell processing method in a communication system capable of communicating with a plurality of radio base station apparatuses by performing a mobile operation of a radio terminal apparatus,
Measurement information indicating measurement results of radio signals transmitted from a plurality of radio base station apparatuses other than the target radio base station apparatus is acquired based on information from at least one of the radio terminal apparatus and the radio base station apparatus And steps to
Based on the acquired measurement information, among the plurality of radio base station apparatuses other than the target radio base station apparatus, one or more radio base station apparatuses arranged around the target radio base station apparatus Generating neighboring cell information indicating
Transmitting the generated neighboring cell information to the target radio base station apparatus or a radio terminal apparatus communicable with the target radio base station apparatus.

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