JP2013098931A - Radio communication system, management device and radio communication method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide radio communication system, management device, and radio communication method, capable of reducing power consumption.SOLUTION: A management femto station 10 includes an other-station mode controller 14 and a self-station mode controller 12. The other-station mode controller 14 instructs the femto station to switch over between a normal mode and a power saving mode that consumes lower power than the normal mode, according to the presence or absence of a mobile station located in the femto station area. When the mobile station leaves from the area managed by the management femto station 10, the self-mode station controller 12 controls to shift to a power saving management mode. The femto station includes a self-station mode controller. According to the above instruction, the self-mode station controller controls to shift between the normal mode and the power saving mode.

Description

  The present invention relates to a wireless communication system, a management apparatus, and a wireless communication method.

  Conventionally, in a wireless communication system to which a wireless communication system such as 3G (Generation) and LTE (Long Term Evolution) is applied, a base station (hereinafter referred to as a “macro station”) that forms a large cell having a radius of about several kilometers. .) Is used. A macro station has a large communication capacity and high output, but on the other hand, in a home, office, or near a boundary between cells, radio waves may be weak and communication with a mobile station may be difficult. Therefore, in recent years, telecommunications carriers have installed multiple small base stations with low capacity and low output (hereinafter referred to as “femto stations”) in limited areas such as homes, offices, and shopping malls. Has expanded the communication range with mobile stations. As a result, the coverage area of the macro station is supplemented by the femto station, and the convenience of the user of the mobile station is improved.

JP 2010-93524 A JP 2010-212998 A JP 2011-87300 A JP 2007-295349 A

  The femto station can improve both the indoor communication area and the communication capacity, but the number of base stations that communicate with the mobile station increases as compared to the case where the cell is covered by a single macro station. Each base station consumes power because it performs operations such as transmission of radio waves of a predetermined intensity or scheduling regardless of the size of the communication area. In particular, in the case of a femto station, unlike a macro station, a single subscriber often sets up a plurality of base stations in the same facility, so there are many in limited areas such as homes, offices, and shopping malls. As femto stations coexist, power consumption increases accordingly. Such an increase in power consumption is not only contrary to the trend of power saving (power saving) in society, but also becomes a factor that hinders the introduction and expansion of femto stations by subscribers.

  The disclosed technology has been made in view of the above, and an object thereof is to provide a wireless communication system, a management device, and a wireless communication method capable of reducing power consumption.

  In order to solve the above-described problems and achieve the object, a wireless communication system disclosed in the present application includes a management device and a first base station that communicates with the management device. The management device includes an instruction unit and a first control unit. The instructing unit switches between the first mode and a second mode with lower power consumption than the first mode according to the presence or absence of a mobile station located in the first base station. Instruct the base station. The first control unit performs control to shift to the second mode when the mobile station leaves the area managed by the management apparatus. The first base station has a second control unit. The second control unit performs control to shift between the first mode and the second mode based on the instruction.

  According to one aspect of the wireless communication system disclosed in the present application, power consumption can be reduced.

FIG. 1 is a diagram illustrating a configuration of a wireless communication system. FIG. 2 is a diagram illustrating a functional configuration of the management femto station. FIG. 3 is a diagram illustrating an example of a located area management table held by the management femto station. FIG. 4 is a diagram illustrating a functional configuration of the monitoring femto station. FIG. 5 is a diagram illustrating a functional configuration of the femto station. FIG. 6 is a diagram illustrating a hardware configuration of the femto station and the mobile station. FIG. 7 is a flowchart for explaining the operation of each femto station when the management mobile station enters the shopping mall. FIG. 8 is a flowchart for explaining the operation of the femto station shifting from the normal mode to the power saving mode. FIG. 9 is a flowchart for explaining the operation of the femto station shifting from the power saving mode to the normal mode. FIG. 10 is a flowchart for explaining the operation of each femto station when the mobile station moves between femto stations. FIG. 11 is a flowchart for explaining an operation in which the monitoring femto station shifts from the monitoring mode to the power saving monitoring mode. FIG. 12 is a flowchart for explaining an operation in which the monitoring femto station shifts from the power saving monitoring mode to the monitoring mode. FIG. 13 is a flowchart for explaining the operation of the femto station when the mobile station leaves the shopping mall. FIG. 14 is a diagram illustrating a correspondence relationship between each femto station and a function.

  Hereinafter, embodiments of a wireless communication system, a management device, and a wireless communication method disclosed in the present application will be described in detail with reference to the drawings. Note that the wireless communication system, the management apparatus, and the wireless communication method disclosed in the present application are not limited by the embodiments.

  First, a configuration of a wireless communication system according to an embodiment disclosed in the present application will be described. FIG. 1 is a diagram illustrating a configuration of a wireless communication system 1. As shown in FIG. 1, the wireless communication system 1 includes at least a management femto station 10, monitoring femto stations 20 and 30, and femto stations 40, 50 and 60. The femto stations 40, 50 and 60 constitute a femto station group G. The management femto station 10 and the monitoring femto stations 20 and 30 are connected by wire so that signals and data can be transmitted and received between them. Further, the management femto station 10 and the femto stations 40, 50, and 60 are connected by wire so that signals and data can be transmitted and received mutually.

  In a present Example, the case where the management femto station 10 manages the femto station 40, 50, 60 arrange | positioned at each shop in a shopping mall is assumed. In addition, the management mobile station 70 is a mobile station held by a manager of a shopping mall, in particular, among mobile stations. When the management femto station 10 detects the management mobile station 70 entering the shopping mall in the morning, the management femto station 10 shifts the femto stations 40, 50, and 60 in the group from the sleep mode described later to the power saving mode. On the other hand, when the management femto station 10 detects the exit of the management mobile station 70 from the shopping mall after the shopping mall is closed, the management femto station 10 shifts the femto station 40, 50, 60 from the normal mode or the power saving mode to the sleep mode. Let

  The management femto station 10 manages the operation modes of the femto stations 40, 50, 60 in the femto station group G. The management femto station 10 has two modes: a management mode and a power saving management mode. In the management mode, the management femto station 10 instructs each of the femto stations 40, 50, 60 configuring the femto station group G to shift to the normal mode, the power saving mode, and the sleep mode. Is not sent or received. On the other hand, in the power saving management mode, the management femto station 10 waits for a mobile station detection report from the monitoring femto stations 20 and 30. Note that the management femto station 10 is not necessarily a base station, and may be a server device or the like that does not have a wireless communication function.

  The monitoring femto stations 20 and 30 are installed near the entrance / exit of the shopping mall. The monitoring femto stations 20 and 30 monitor the entrance / exit of the mobile station to / from the shopping mall and notify the management femto station 10 of the monitoring result. The monitoring femto stations 20 and 30 have two modes: a monitoring mode and a power saving monitoring mode. In the monitoring mode, the monitoring femto stations 20 and 30 determine the entering and leaving areas of the mobile station by TAU (Tracking Area Update). As the shopping mall closes and the femto stations 40, 50, 60 shift to the dormant mode, the monitoring femto stations 20, 30 shift to the power saving monitoring mode. Monitor for entry.

  The femto stations 40, 50, 60 are installed at each store in the shopping mall. The femto stations 40, 50, 60 have three modes: a normal mode, a power saving mode, and a sleep mode. First, the normal mode is a mode in which both wired communication and wireless communication operate. In the normal mode, the femto stations 40, 50, and 60 perform outgoing / incoming calls and transmission / reception of various data to / from mobile stations located in a cell formed by each femto station, In-zone determination by pseudo-paging is performed at a period (for example, 10 minutes). Here, pseudo-paging means that each femto station 40, 50, 60 intermittently transmits radio waves, thereby transmitting a pseudo-paging signal to subordinate mobile stations, thereby determining the location of the mobile station. It is to confirm.

  Second, the power saving mode is a mode in which wired communication operates but a part of wireless communication stops. In the power saving mode, the femto stations 40, 50, and 60 perform pseudo-paging location determination at a predetermined cycle (for example, 10 minutes) with respect to the mobile station without performing outgoing / incoming calls or transmission / reception of various data. Do. In the power saving mode, the femto stations 40, 50, 60 stop the RF circuit between pseudo pagings, thereby suppressing unnecessary power consumption and reducing power consumption. Third, the sleep mode is a mode in which wired communication operates but all wireless communication stops. In the dormant mode, the femto stations 40, 50, 60 return to the power saving mode in accordance with an activation instruction received from the management femto station 10 via a wired line without performing transmission / reception of radio waves.

  Since the power consumption of the femto stations 40, 50, and 60 mainly increases and decreases due to the amount of radio waves transmitted and received, the power consumption is the smallest in the sleep mode without wireless communication, and then only wireless communication by pseudo paging is performed. Less in power mode. In the normal mode in which various services are provided via wireless communication, the largest amount of power is consumed.

  Hereinafter, the configuration of each of the femto stations 10 to 60 will be described with reference to FIGS.

  FIG. 2 is a diagram illustrating a functional configuration of the management femto station 10. As shown in FIG. 2, the management femto station 10 includes a communication unit 11, a local station mode control unit 12, a located state management table 13, an other station mode control unit 14, a time measuring unit 15, and the number of mobile stations. And a determination unit 16. Each of these components is connected so that signals and data can be input and output in one direction or in both directions. The communication unit 11 receives a message notifying that the managed mobile station 70 has entered the service area. The own station mode control unit 12 causes the mode of the management femto station 10 to shift from the power saving management mode to the management mode when receiving the message.

  FIG. 3 is a diagram illustrating an example of the located area management table 13 held by the management femto station 10. As shown in FIG. 3, the current state of each femto station 20, 30, 40, 50, 60 is maintained in the visited state management table 13 in an updatable manner, and the mobile station in each femto station The situation is maintained for each mobile station. For example, when the mobile station 100 is located in the femto station 40 and the mobile station 100 moves to another femto station 50, the mode of the femto station 40 is changed from “normal mode” at the next pseudo paging timing. Updated to “Power Save Mode”. At the same time, the location status of the femto station 40 of the mobile station 100 becomes “absent”, and the location status of the femto station 50 is updated to “location”. As described above, the management femto station 10 can communicate with any femto station by referring to the in-zone management table 13 so that the mode of each femto station other than the own station and each mobile station in the shopping mall can communicate. It can be easily and quickly ascertained.

  The other station mode control unit 14 instructs the monitoring femto stations 20 and 30 and the femto stations 40, 50, and 60 to shift modes. The time measuring unit 15 has a clock function, and requests the other station mode control unit 14 to make a mode change instruction to each of the femto stations 20 to 60 when the current time is the opening time of the shopping mall. The mobile station number determination unit 16 refers to the above-described visited area management table 13 and counts the number of registered mobile stations located in the femto station identified as the movement source among the femto stations 40, 50, and 60. Then, it is determined whether or not the counting result is “0”.

  FIG. 4 is a diagram illustrating a functional configuration of the monitoring femto station 20. As shown in FIG. 4, the monitoring femto station 20 includes a communication unit 21, an entrance monitoring unit 22, and a local station mode control unit 23. Each of these components is connected so that signals and data can be input and output in one direction or in both directions. The communication unit 21 receives a mode transition instruction transmitted from the management femto station 10 when the management mobile station 70 enters the service area. The entrance monitoring unit 22 determines whether or not each mobile station 70, 80, 90, 100 has received a TAU transmitted when the mobile station 70, 80, 90, 100 enters the shopping mall. Monitor entry and departure from shopping malls. The own station mode control unit 23 controls the return from the power saving monitoring mode to the monitoring mode or the transition from the monitoring mode to the power saving monitoring mode in accordance with an instruction from the management femto station 10.

  The functional configuration of the monitoring femto station 20 has been described above. However, the functional configuration of the monitoring femto station 30 is the same as that of the monitoring femto station 20, and therefore common components have the same suffix as necessary. Reference numerals are attached, and illustration and detailed description thereof are omitted.

  FIG. 5 is a diagram illustrating a functional configuration of the femto station 40. As shown in FIG. 5, the femto station 40 includes a communication unit 41, a local station mode control unit 42, a mobile station type determination unit 43, a located area monitoring unit 44, and a time measuring unit 45. Each of these components is connected so that signals and data can be input and output in one direction or in both directions. The communication unit 41 receives a mode transition instruction transmitted from the management femto station 10 at the opening time. The own station mode control unit 42 performs control to shift the own station from the sleep mode to the power saving mode in accordance with the mode change instruction. Based on the RRC CONNECTION REQUEST transmitted from each mobile station 70, 80, 90, 100, the mobile station type determination unit 43 determines TMSI (Temporary Mobile Subscriber Identity) indicating the type of mobile station of the transmission source. The location monitoring unit 44 generates a pseudo-paging message, transmits this message to each registered mobile station 70, 80, 90, 100, and based on whether there is a response to the message, Judgment of absence (absence). The time measuring unit 45 has a clock function, and when the current time is close to the closing time of the shopping mall (for example, 19:45), the timer mode control unit 42 is in a pause mode of the femto station 40. Request a transition to.

  Although the functional configuration of the femto station 40 has been described above, the functional configuration of the femto stations 50 and 60 is the same as that of the femto station 40. A reference numeral is attached, and illustration and detailed description thereof are omitted.

  FIG. 6 is a diagram illustrating a hardware configuration of the management femto station 10 and the management mobile station 70. As shown in FIG. 6, the management femto station 10 includes a CPU (Central Processing Unit) 10a, a memory 10b, an RF circuit 10c, and a network IF (InterFace) 10d as hardware components. Each of these components is connected so that various signals and data can be input and output in one or both directions. The RF circuit 10c has an antenna A1. The memory 10b includes, for example, a RAM such as SDRAM (Synchronous Dynamic Random Access Memory), a ROM (Read Only Memory), and a flash memory. The management mobile station 70 includes a CPU 70a, a memory 70b, and an RF circuit 70c as hardware components. The RF circuit 70c has an antenna A2.

  Specifically, the communication unit 11 of the management femto station 10 is realized by the RF circuit 10c. The own station mode control unit 12, the timing unit 15, and the mobile station number determination unit 16 are realized by the CPU 10a. The located state management table 13 is realized by the memory 10b. The other station mode control unit 14 is realized by the CPU 10a and the network IF 10d.

  The hardware configuration of the management femto station 10 has been described above representatively, but the hardware configurations of the monitoring femto stations 20 and 30 and the femto stations 40, 50, and 60 are the same as those of the management femto station 10, and thus are common. Constituent parts are denoted by the same reference numerals at the end, and illustration and detailed description thereof are omitted. Also, since the hardware configuration of the mobile stations 80, 90, 100 is the same as that of the management mobile station 70, common components are denoted by the same reference numerals at the end, and illustration and detailed description thereof are omitted. .

  Regarding the monitoring femto stations 20 and 30, specifically, the communication units 21 and 31 are realized by network IFs 20d and 30d, respectively. Further, the entrance monitoring units 22 and 32 are realized by the RF circuits 20c and 30c, respectively. Furthermore, the own station mode control units 23 and 33 are realized by the CPUs 20a and 30a, respectively. On the other hand, regarding the femto stations 40, 50, and 60, specifically, the communication units 41, 51, and 61 are realized by network IFs 40d, 50d, and 60d, respectively. The own station mode control units 42, 52, 62, the mobile station type determination units 43, 53, 63, and the time measuring units 45, 55, 65 are realized by the CPUs 40a, 50a, 60a, respectively. Further, the in-zone monitoring units 44, 54, and 64 are realized by the RF circuits 40c, 50c, and 60c, respectively.

  Next, the operation of the wireless communication system 1 according to the present embodiment will be described.

  First, the operation of each femto station when the shopping mall is opened will be described. FIG. 7 is a flowchart for explaining the operation of each femto station when the management mobile station 70 enters the shopping mall. As a premise for explaining the operation, when the shopping mall is opened (initial state), each of the femto stations 10 to 60 is set to a mode with the least power consumption. That is, the management femto station 10 is in the power saving management mode, the monitoring femto stations 20, 30 are in the power saving monitoring mode, and the femto stations 40, 50, 60 are in the sleep mode.

  In S1, the CPUs 20a and 30a of the monitoring femto stations 20 and 30 installed near the entrance of the mall are waiting to receive TAU. When an administrator (for example, a clerk) who owns the management mobile station 70 goes to work, the management mobile station 70 performs an area update (Area Update) from the communication area of the macro base station to the communication area of the femto base station. Send TAU. When the RF circuit 20c of the monitoring femto station 20 among the plurality of monitoring femto stations 20 and 30 receives the TAU from the management mobile station 70, the CPU 20a receives the TAU and the management mobile station 70 enters the shopping mall. This is detected (S2; Yes), and a notification to that effect is sent to the management femto station 10 (S3). Note that the CPU 20a continues to wait for TAU reception while it does not detect the entrance of the management mobile station 70 (S2; No).

  In S4, when the CPU 10a of the management femto station 10 receives a notification from the monitoring femto station 20 that the management mobile station 70 has entered the shopping mall (S3), the CPU 10a changes its own mode from the power saving mode to the management mode. (S4). Accordingly, the CPU 10a updates the mode of the local station in the area status management table 13 and updates the area status of the area status management table 13, so that the management mobile station 70 can select any femto station at present. It becomes possible to recognize whether the area is under the service (S5). After updating the table, the network IF 10d transmits a signal instructing the shift to the monitoring mode to the monitoring femto stations 20 and 30 (S6). When the monitoring femto stations 20 and 30 receive the signals through the network IFs 20d and 30d, the monitoring femto stations 20 and 30 shift from the previous power saving monitoring mode to the monitoring mode (S7).

  In S8, the CPU 10a of the management femto station 10 determines whether or not the current time is the opening time of the shopping mall by the clock function, and only when the current time is the opening time (S8; Yes), The femto stations 40, 50, 60 are instructed to change modes (S9). Note that the current time does not necessarily coincide with the opening time. For example, the current time may have a width before or after the opening time from 1 hour before the opening time (for example, 9:00 to 10:00). Also good. As a result, when the administrator comes back to the shopping mall for some reason, for example, when the administrator returns to the store, each femto station 40, 50, 60 returns from the sleep mode regardless of the opening time. And the situation of consuming unnecessary electric power is avoided. Therefore, an increase in power consumption is suppressed and efficient power use is possible. In S10, each femto station 40, 50, 60 that received the instruction in S9 shifts from the sleep mode to the power saving mode. Furthermore, the femto stations 40, 50, 60 in the power saving mode shift to the normal mode according to the mode change instruction from the management femto station 10 when detecting the mobile station entering the local station. The instruction between these femto stations is realized by the management femto station 10 transmitting a command issued using a mechanism based on the Simple Object Access Protocol (SOAP) protocol or TR-069 via a wired line. Is done.

  Here, the femto stations that shift to the power saving mode in response to the mode shift instruction in S9 are not necessarily all the femto stations that belong to the femto station group G. That is, according to the owner of the management mobile station that notified the entrance in S3, the installation location of the monitoring femto station that detected the entrance, date, time (including time zone), day of the week, etc., the management femto station 10 The femto station that is returned to the power saving mode may be changed as appropriate. In addition, the management femto station 10 determines the femto stations 40, 50, 60 based on the location of the store where the femto station is installed, the business hours, the target layer, the contents of products and services, and the types of events and seminars being held. Of these, it may be determined which femto station is returned to the power saving mode.

  In addition, it is assumed that the user of the registered mobile station is lined up near the entrance from the opening time on the special day of the shopping mall. In such a case, the CPUs 20a, 30a of the monitoring femto stations 20, 30 may count the number of registered mobile stations located near the entrance of the shopping mall. The CPU 10a of the management femto station 10 determines whether or not it is a special sale date from the number of registered mobile stations located near the mall entrance (for example, 30 to 50 or more). It is good also as what distributes the coupon information for special sales and the price information of goods to a station. Furthermore, when the count value of the number of registered mobile stations exceeds a predetermined value (for example, 100), the CPU 10a of the management femto station 10 pauses each femto station 40, 50, 60 regardless of the current time. The mode may be returned to the power saving mode. Thereby, the user of the registered mobile station can enter the shopping mall and receive services provided from the femto stations 40, 50, 60 without waiting for the opening time. As a result, congestion near the entrance is alleviated.

  FIG. 8 is a flowchart for explaining the operation of the femto station 40 shifting from the normal mode to the power saving mode. In S11 of FIG. 8, the CPU 50a of the femto station 50 generates a pseudo paging message. When the RF circuit 50c pages the generated message using RRC (Radio Resource Control), the mobile station 80 receives this message (S12). When the mobile station is not located in the cell of the femto station 50, the above-described processing of S11 is executed again (S13), but when the mobile station (for example, the mobile station 80) is located, the RF circuit 50c receives the RRC CONNECTION REQUEST transmitted from the mobile station 80 (S14).

  In S15, the CPU 50a determines the type (the above-mentioned TMSI) of the transmission source mobile station 80 based on the RRC CONNECTION REQUEST received in S14. Here, the type of mobile station is determined mainly based on the presence or absence of registration for the femto station group G. There are three types of mobile stations: managed mobile stations, registered mobile stations, and general mobile stations. The management mobile station is a mobile station for the monitoring femto stations 20 and 30 to switch between the modes (monitoring mode and power saving monitoring mode), and is used by a shopping mall administrator. A registered mobile station is a mobile station (subscriber terminal) registered in the femto station group G and capable of making and receiving calls within the cell of each femto station 40, 50, 60, and is used by registered users. A general mobile station is a mobile station (guest terminal) that is not registered in the femto station group G, and is used by a general user. Among these mobile station types, the management mobile station and the registered mobile station are the target mobile stations for pseudo-paging in the wireless communication system 1. The registered mobile station is a distribution target of various services (coupons and special sale information) provided from each store within the femto station group G.

  In S15, when the determination result of the mobile station type is other than the registered mobile station, the above-described process of S11 is executed again (S16). On the other hand, if the determination result is a registered mobile station, the RF circuit 50c returns REJECT to the RRC CONNECTION REQUEST received from the mobile station 80 in S14 (S17). After the REJECT response, the network IF 50d reports the entrance of the mobile station 80 to the management femto station 10 (S18), and then executes the processing from S11 again (S19).

  In S <b> 20, the CPU 10 a of the management femto station 10 identifies the source femto station of the mobile station 80 with reference to the located state management table 13. For example, when the mobile station 80 moves from the femto station 40 to the femto station 50, the location status of the femto station 40 related to the mobile station 80 is updated from “present location” to “absent”. It can be determined that the original is the femto station 40. The CPU 10a counts the number of registered mobile stations located in the femto station 40 specified as the movement source by referring to the located state management table 13, and determines whether or not the counting result is “0”. . When the count result is “0”, the CPUa of the management femto station 10 determines that the registered mobile station is not located in the femto station 40, and the network 10 d saves the femto station 40. An instruction to shift to the power mode is transmitted (S21). The femto station 40 that has shifted to the power saving mode performs intermittent pseudo-paging in preparation for the new mobile station entering the area, but since it is in the power saving mode, it stops other wireless communication functions such as providing services. To do. Then, the network IF 10d of the management femto station 10 instructs the femto station 50 that is the transmission source of the location report of the mobile station 80 to shift to the normal mode for providing the mobile station 80 with various services ( S22).

  In addition, when executing the above-described mobile localization sphere determination process, each femto station 40, 50, 60 performs pseudo-paging on all registered mobile stations, but not all registered mobile stations are necessarily registered. There is no need for pseudo-paging. That is, each femto station 40, 50, 60 may narrow down the target mobile stations for pseudo-paging to the mobile stations that have performed TAU transmission among the registered mobile stations. Thereby, the transmission / reception amount of radio waves accompanying pseudo-paging (intermittent radio wave transmission) decreases. Therefore, each femto station 40, 50, 60 can further reduce power consumption in the power saving mode.

  In addition, each femto station 40, 50, 60 detects the presence / absence of each mobile station 70 to 100 by pseudo-paging, but at the timing of pseudo-paging, between each femto station 40, 50, 60 The synchronization is achieved. For this reason, the in-zone states of the mobile stations 70 to 100 do not overlap between different femto stations.

  Next, an operation in which the femto station shifts from the power saving mode to the normal mode will be described. FIG. 9 is a flowchart for explaining the operation of the femto station 50 shifting from the power saving mode to the normal mode. In S31, the femto station 50 is in the power saving mode, and the RF circuit 50c periodically monitors the presence or absence of the mobile station by performing pseudo-paging. The monitoring is performed until the CPU 50a detects the location of the registered mobile station in the femto station 50. When the CPU 50a detects the location of the registered mobile station (S32; Yes), the network IF 50d passes through the network IF 50d. The management femto station 10 is notified of the location of the registered mobile station (S33).

  When the CPU 10a of the management femto station 10 receives a notification from the femto station 50 that the registered mobile station is located in the femto station 50 (S33), the CPU 10a changes the mode of the femto station 50 in the located state management table 13 to the previous mode. The power saving mode is updated to the normal mode (S34). As a result, the management femto station 10 can recognize which mode the femto station 50 is currently set to. After updating the table, the network IF 10d of the management femto station 10 transmits a signal instructing the femto station 50 to shift to the normal mode (S35). When the femto station 50 receives the signal through the network IF 50d, the femto station 50 shifts from the previous power saving mode to the normal mode (S36). As a result, the femto station 50 is in a state where it can make and receive calls with mobile stations located in its own station and provide various services.

  Next, the operation of each femto station when the mobile station moves between femto stations will be described. FIG. 10 is a flowchart for explaining the operation of each of the femto stations 10 to 60 when the mobile station 80 moves between the femto stations 40, 50, and 60. In S41, the femto station 40 is in the normal mode, and the RF circuit 40c periodically monitors the presence or absence of the mobile station by performing pseudo-paging. The monitoring is performed until the CPU 40a detects the absence of the registered mobile station in the femto station 40. When the CPU 40a detects the absence of the registered mobile station 80 (S42; Yes), the registration is performed via the network IF 40d. The absence of the mobile station 80 is notified to the management femto station 10 (S43).

  When the CPU 10a of the management femto station 10 receives a notification from the femto station 40 that the registered mobile station 80 is absent from the femto station 40 (S43), the registered mobile station 80 leaves the other femto station. Estimated. Then, the network IF 10d transmits a search request for the registered mobile station 80 to the other femto stations 50 and 60 (S44, S45). The RF circuit 50c of the femto station 50 that has received the search request tries to detect the registered mobile station 80 by performing pseudo-paging similar to S41 (S46) in its own station (S47).

  In S <b> 48, the network IF 50 d notifies the management femto station 10 of the presence or absence of the area depending on whether or not the registered mobile station 80 can be detected. That is, when the registered mobile station 80 is detected, the network IF 50d notifies that the registered mobile station 80 is in the femto station 50. Conversely, when the registered mobile station 80 is not detected. The registered mobile station 80 notifies the femto station 50 that it is not located. Such notification of in-zone or out-of-zone is similarly executed for the femto station 60 (S49 to S51).

  In S52, the CPU 10a of the management femto station 10 updates the in-zone state management table 13 according to the detection result of the registered mobile station 80 in each femto station 40, 50, 60 (S52). For example, when the mobile station 80 that is no longer detected by the femto station 40 is detected by the femto station 60, the CPU 10 a changes the location status of the mobile station 80 to “Femto station 40: location, femto station 60. : "Absent" to "femto station 40: absent, femto station 60: within range". As a result, the data in the located state management table 13 is updated to the latest state, and the management femto station 10 refers to the located state management table 13 so that the registered mobile station 80 is located in any femto station at this time. Can be easily recognized. At this time, if the CPU 10a takes a history of the location status and refers to the information, the CPU 10a can grasp which femto station the mobile station 80 has moved from which femto station (movement status). it can.

  After the table update, the network IF 10d of the management femto station 10 notifies the femto stations 50 and 60 that have notified the location status in S48 and S51 that the update of the location status management table 13 has been completed. (S53, S54). Further, the network IF 10d transmits a signal instructing the shift to the power saving mode to the femto station 40 (S55). When the femto station 40 receives the signal via the network IF 40d, the femto station 40 shifts from the previous normal mode to the power saving mode (S56).

  Subsequently, the mode transition operation of the monitoring femto stations 20 and 30 will be described. In this embodiment, the transition operation of the monitoring femto station 20 will be described as a representative, but the same operation is performed for the monitoring femto station 30 as well. FIG. 11 is a flowchart for explaining an operation in which the monitoring femto station 20 shifts from the monitoring mode to the power saving monitoring mode.

  First, in S61, the CPU 10a of the management femto station 10 searches the femto stations 40, 50, and 60 for one femto station to be subjected to mode determination. In S62, the CPU 10a determines whether or not the counter n of the number of femto stations is “0”. In this embodiment, since the number of femto stations is three, “3” is set as the initial value of the counter n.

  If n = 0 is not satisfied as a result of the determination (S62; No), the CPU 10a determines the current mode for the femto station searched in S61 (S63). This determination is made with reference to the located state management table 13. As a result of the determination, if the current mode is not the normal mode (S63; No), the CPU 10a decreases the value of the current femto station number counter n by 1 and sets n = n−1 (S64). Thereafter, the process returns to S61, and the CPU 10a repeatedly executes the series of processes of S61 to S64 described above until n = 0. When the femto station counter n reaches “0” in S62 (S62; Yes), all the femto stations 40, 50, 60 in the femto station group G have completed the transition from the normal mode. Presumed. Therefore, in such a case, the CPU 10a omits the processes of S63 and S64 and executes the processes after S65.

  In S65, the CPU 10a refers to the located state management table 13 and determines whether or not the managed mobile station 70 is located in the femto station searched in S61. As a result of the determination, if the managed mobile station 70 is not located (S65; No), the CPU 10a causes all the femto stations in the femto station group G to shift to the power saving mode, and which of the managed mobile stations 70 is It is estimated that the femto station of no longer exists. In S <b> 66, the CPU 10 a refers to the located state management table 13, confirms the estimation result, and then changes the located state management table 13 from “monitor mode” to “power saving monitor mode” for the monitoring femto station 20. Update to be changed is performed (S66).

  Note that if the result of determination in S63 is that the femto station subject to mode determination is in the normal mode (S63; Yes), the CPU 10a does not decrease the value of the femto station number counter n and ends the processing in S64. Similarly to the above, the processing after S61 is executed again. Similarly, when the management mobile station 70 is located in any femto station as a result of the determination in S65 (S65; Yes), the CPU 10a similarly performs S61 to continue the monitoring mode of the monitoring femto station 20. The subsequent processing is executed again.

  After updating the table in S66, the network IF 10d of the management femto station 10 transmits a signal instructing the shift to the power saving monitoring mode to the monitoring femto station 20 (S67). When the monitoring femto station 20 receives the signal through the network IF 20d, the monitoring femto station 20 shifts from the previous monitoring mode to the power saving monitoring mode (S68). Thereby, in addition to the transition of the femto stations 40, 50, 60 to the power saving mode, the transition of the monitoring femto station 20 to the power saving monitoring mode is finally completed.

  FIG. 12 is a flowchart for explaining an operation in which the monitoring femto station 20 shifts from the power saving monitoring mode to the monitoring mode. In S71 of FIG. 12, the CPU 20a of the monitoring femto station 20 waits for reception of TAU. When the RF circuit 20c of the monitoring femto station 20 receives the TAU from the management mobile station 70, the CPU 20a detects the entrance of the management mobile station 70 (S72; Yes), and notifies the management femto station 10 to that effect. (S73). In S74, the CPU 10a of the management femto station 10 that has received the notification of entering the management mobile station 70 shifts the mode of the local station from the power saving mode to the management mode (S74). Accordingly, the CPU 10a updates the mode of the own station in the located state management table 13 and the located state of the managed mobile station 70 (S75). After updating the table, the network IF 10d transmits a signal instructing the shift to the monitoring mode to the monitoring femto station 20 (S76). When the monitoring femto station 20 receives the signal through the network IF 20d, the monitoring femto station 20 shifts from the previous power saving monitoring mode to the monitoring mode (S77). Further, the network IF 10d of the management femto station 10 transmits a signal instructing the transition from the sleep mode to the power saving mode to all the femto stations 40, 50, 60 belonging to the femto station group G (S78).

  In S78, the management femto station 10 may directly instruct the femto stations 40, 50, and 60 to shift from the sleep mode to the normal mode without going through the power saving mode.

  Next, the operation of each femto station when the mobile station leaves the shopping mall will be described. FIG. 13 is a flowchart for explaining the operation of the femto station 40 when the mobile station 80 leaves the shopping mall. Hereinafter, the operation of the femto station 40 will be described on the assumption that the business hours of the shopping mall are 10:00 to 20:00 and the operation hours of the femto stations 40, 50, and 60 are also set in this time zone. In the present embodiment, the operation of the femto station 40 will be described representatively, but the same operation is performed for the other femto stations 50 and 60.

  In S81, the CPU 40a of the femto station 40 determines whether or not the current time is 19:45, that is, 15 minutes before the closing time, by the clock function. As a result of the determination, if it is not past 19:45 (S81; No), the RF circuit 40c continues the pseudo-paging of a predetermined period (S82), and whether the mobile station is in the area of the femto station 40 or not. It is determined whether or not (S83). When the mobile station is in the area (S83; No), the process returns to S81, and the femto station 40 repeatedly executes the processes after S81, but when it is not in the area (S83; Yes), the network IF 40d The absence of the mobile station is notified to the management femto station 10 (S84).

  In the management femto station 10 that has received the absence notification, the CPU 10a updates the mode of the femto station 40 in the location state management table 13 from the normal mode to the power saving mode (S85). After the table update, the network IF 10d transmits a signal instructing the femto station 40 to shift to the power saving mode or the sleep mode (S86).

  In S87, the same process as in S81 is executed. That is, the CPU 40a of the femto station 40 determines whether or not the current time is after 19:45 by the clock function, and executes the mode shift according to the result. For example, when the current time is before 19:45 (S87; No), there is time until the closing time, so the CPU 40a shifts the own station to the power saving mode (S88). Thereafter, the process returns to S81 again, and the processes after S81 are repeatedly executed. On the other hand, when the current time is past 19:45 (S87; Yes), since the store closing time is not reached, the CPU 40a directly shifts the own station to the sleep mode without going through the power saving mode (S89). ). As a result, the femto station 40 quickly enters a dormant state.

  Even after the transition to any mode, the network IF 40d of the femto station 40 notifies the management femto station 10 of the mode of the transition destination (S90, S91). As a result, the management femto station 10 can easily and quickly grasp which mode the femto station 40 has shifted to between the power saving mode and the hibernation mode. The mode of the transfer destination is reflected in the in-zone state management table 13 as the current mode of the femto station 40 (see FIG. 3).

  As a result of the determination in S81, when the current time is past 19:45 (S81; Yes), the CPU 40a of the femto station 40 determines the current mode of the own station (S92). As a result of the determination, if the current mode is not the power saving mode (S92; No), the CPU 40a determines that there is a mobile station that is still in the femto station 40 in the normal mode, and the pseudo-paging described above. Is continuously executed (S82). On the other hand, when the current time is past 19:45 and the femto station 40 is in the power saving mode (S92; Yes), there is no registered mobile station located in the femto station 40 at that time. Can be judged. Therefore, the CPU 40a shifts the mode of the own station from the power saving mode to the sleep mode in order to quickly stop the femto station 40 (S93). Thereafter, the network IF 40d of the femto station 40 notifies the management femto station 10 of the transfer destination mode (S94). Since the femto station 40 stops the pseudo-paging by shifting to the dormant mode, even if the registered mobile station enters the femto station 40 after 19:45, it does not return to the normal mode again. .

  In addition, even when the management mobile station 70 becomes non-resident from the monitoring femto stations 20 and 30 and is deleted from the located state management table 13 with the closing of the shopping mall, the femto stations 40 in the femto station group G are also included. , 50, 60 all enter the sleep mode. At the same time, the monitoring femto stations 20 and 30 shift to the power saving monitoring mode.

  Regarding the method of transition from the normal mode to the power saving mode by the femto station 40, for example, when the mobile station 80 moves from the area of the femto station 40 to the area of the femto station 50, the femto station 50 causes the mobile station 80 to Detect that has entered the service area of its own station. When the femto station 50 notifies the management femto station 10 that the mobile station 80 has entered the network, the management femto station 10 refers to the in-zone state management table 13 and then checks whether there is another mobile station in the femto station 40. When the management femto station 10 confirms that no other mobile station exists, the management femto station 10 determines that the femto station 40 can shift to the power saving mode, and sends the power saving mode to the femto station 40 via the wired line. Send migration instructions.

  On the other hand, regarding the method of returning from the power saving mode to the normal mode by the femto station 40, for example, when the mobile station 90 moves from the area of the femto station 60 to the area of the femto station 40 in the power saving mode, the femto station 40 Transits to the normal mode. That is, since the femto station 40 periodically performs pseudo-paging even after shifting to the power saving mode, a mobile station that has moved into the area of the femto station 40 responds to the paging. The location can be detected. Thereafter, the femto station 40 waits for an instruction from the management femto station 10 and returns to the normal mode again. The management femto station 10 updates the mode of the femto station 40 in the in-zone state management table 13 from “power saving mode” to “normal mode”, and also changes the femto station in which the mobile station 90 is located to “femto station 60”. To “Femto station 40”.

  Further, regarding the method of transitioning to the suspension mode by the femto stations 40, 50, 60, for example, when the shopping mall business hours end, each of the femto stations 40, 50, 60 transitions to the suspension mode, and both wireless and wired Stop the function. As a result, the mode of each femto station in the located state management table 13 is updated to “pause mode”. At the same time, since the monitoring femto stations 20 and 30 also shift to the power saving monitoring mode, the mode of the monitoring femto stations 20 and 30 in the in-zone state management table 13 is changed from “monitoring mode” to “power saving monitoring mode”. Updated. Then, the management femto station 10 enters a standby state for mobile station detection reports from the monitoring femto stations 20 and 30.

  On the other hand, regarding the return method from the sleep mode by the femto stations 40, 50, 60, the monitoring femto stations 20, 30 in the power saving monitoring mode detect a mobile station entry area by TAU, And report to that effect. Also, the own station returns to the monitoring mode. Accordingly, the mode of the monitoring femto stations 20 and 30 in the located state management table 13 is updated from “power saving monitoring mode” to “monitoring mode”. At the same time, the management femto station 10 that has received the mobile station detection report issues an instruction to shift to the power saving mode from the sleep mode to each of the femto stations 40, 50, and 60 using the WakeupOnLAN function. As a result, the mode of each femto station in the location status management table 13 is once updated from the “pause mode” to the “power saving mode”. Thereafter, for example, when a mobile station enters the cell of the femto station 50, the femto station 50 shifts from the power saving mode to the normal mode, and accordingly, the location state management table 13 is also updated to “normal mode”. The However, the modes of the other femto stations 40 and 60 where the mobile station does not enter are maintained in the “power saving mode”.

  Each femto station 40, 50, 60 determines the presence or absence of the mobile station by pseudo-paging, but the mobile station takes a long time (for example, 3 hours to 10 hours) for pseudo-paging. If the user responds, there is a high possibility that the user has left the mobile station. Therefore, when the response from the mobile station continues for a long time, each femto station 40, 50, 60 estimates that the user dropped the mobile station in the store or left home at the company's own seat, The mobile station is excluded from the target of pseudo paging. This prevents erroneous determination of the presence / absence of the mobile station by the femto stations 40, 50, 60. Accordingly, since the mobile station exists even though the power saving mode or the hibernation mode can be originally saved and the mobile station exists, the management femto station 10 sets each of the femto stations 40, 50, 60 to these The inconvenience that the mode cannot be shifted to this mode is avoided. As a result, the opportunity loss for reducing power consumption is reduced, and further power saving can be realized.

  In the above embodiment, each of the femto stations 40, 50, 60 is assumed to shift from the sleep mode to the power saving mode in response to an instruction (command) from the management femto station 10. It is good also as what transfers to normal mode directly from dormant mode, without going through.

  As described above, the wireless communication system 1 includes the management femto station 10 and the femto station 40 that communicates with the management femto station 10. The management femto station 10 includes an other station mode control unit 14 and a local station mode control unit 12. For example, the other station mode control unit 14 switches between the normal mode and the power saving mode in which the power consumption is lower than the normal mode, depending on the presence or absence of the mobile stations 70 to 100 located in the femto station 40. Instruct the femto station 40. The own station mode control unit 12 performs control to shift to the power saving management mode when the mobile stations 70 to 100 are separated from the area (shopping mall) managed by the management femto station 10. Further, the femto station 40 includes a local station mode control unit 42 that performs control to shift between the normal mode and the power saving mode based on the above instruction.

  The other station mode control unit 14 of the management femto station 10 moves the femto to the sleep mode in which the power consumption mode is lower than the power saving mode when the mobile stations 70 to 100 are separated from the area managed by the management femto station 10. The station 40 may be instructed. Further, the other station mode control unit 14 of the management femto station 10 shifts to the power saving monitoring mode when the mobile stations 70 to 100 are out of the area managed by the management femto station 10. The monitoring femto station 20 that monitors the presence / absence of entry into the area (shopping mall) may be instructed.

  As described above, the management femto station 10 cooperates with the other femto stations 20 to 60 to save power in the wireless communication system 1. That is, if there is no registered mobile station located in each femto station 40, 50, 60, the management femto station 10 switches the mode of the corresponding femto station to the power saving mode, so that the femto station group G Degenerate femto station functions that are not being used. In addition, when all registered mobile stations have departed from the shopping mall, the management femto station 10 shifts itself to the power saving mode to further save power. Furthermore, the management femto station 10 shifts the femto stations 40, 50, and 60 to a sleep mode in which the power consumption is lower than the power saving mode and monitors when all registered mobile stations have moved away from the shopping mall. The femto stations 20 and 30 are also shifted to the power saving mode. Thereby, the power consumption of the entire system is further reduced.

  In addition, although the case where the radio | wireless communications system 1 was applied to a shopping mall was illustrated in the said Example, the radio | wireless communications system 1 can also be applied not only to this but to an office building or a house. For example, in an application example to an office building, femto stations 40, 50, 60 are arranged on each floor of the building. When all employees working on the 2nd floor move to the 1st floor meeting room to attend the meeting, the 2nd floor femto station 50 waits for instructions from the management femto station 10 to save power. Switch to mode and stop transmitting / receiving radio waves. After the meeting, when the employee returns to his / her seat again, the femto station 50 on the second floor recovers its function and resumes providing services to the mobile stations 70 to 100 of each employee, and the femto station 40 on the first floor Shift to power saving mode again. Thereafter, when all employees return home after one day's work, or when all employees are absent on a holiday, the femto stations 40, 50, 60 shift to a sleep mode with a higher power saving effect. When the employee goes to work, the monitoring femto stations 20 and 30 detect the re-entry area of the registered mobile station and request the management femto station 10 to return to the mode of the femto stations 40, 50, and 60.

  For example, in an application example to a three-story detached house, the femto stations 40, 50, and 60 are arranged at predetermined positions on each floor. When a child who has been provided with a service by the femto station 60 in the third floor own room moves to the table on the second floor for dinner, the femto station 60 on the third floor waits for an instruction from the management femto station 10, Switch to power saving mode and stop transmitting / receiving radio waves. After the meal is over, the parent moves to the living room on the first floor and watches the television, but the child returns to his room to email with a friend. Along with this, the femto stations 40 and 60 on the first floor and the third floor restore their functions and resume providing services, but the femto station 50 on the second floor shifts from the normal mode to the power saving mode. After that, when the whole family goes to bed, all femto stations are not used, so the femto stations 40, 50, 60 shift to the power saving mode. When the whole family goes to work or goes to school in the morning, or when the whole family goes out on a holiday, all registered mobile stations are absent in the house, so the femto stations 40, 50, 60 are more Transition to hibernation mode with high power saving effect. Then, when any of the family members come home, the monitoring femto stations 20 and 30 detect the re-entry area of the registered mobile station and notify the management femto station 10 of the necessary femto station (for example, the femto station 50 near the kitchen). ) Request mode return. In any of the application examples described above, the number of managed mobile stations is not limited to one, and it does not prevent that there are a plurality (for example, the number of stores, the number of floors, the number of rooms).

  In the above embodiment, a mobile station, a mobile phone, a smart phone, and a PDA (Personal Digital Assistant) have been described as mobile stations. However, the present invention is not limited to a mobile station, and various mobile stations can communicate with a femto station. Applicable to communication equipment.

  In the above embodiment, the number of management mobile stations 70 is one, but there may be a plurality. Thereby, the management femto station 10 can individually set the femto station to be shifted from the sleep mode to the power saving mode according to the administrator who holds the management mobile station 70. That is, in the above-described embodiment, all the femto stations 40, 50, and 60 are collectively shifted to the power saving mode as the managed mobile station 70 enters the area. However, for example, when the management target of the manager of the management mobile station 70 is a store where the femto stations 40 and 50 are installed, the management femto station 10 shifts only the femto stations 40 and 50 to the power saving mode. Thereafter, when another managed mobile station that manages the femto station 60 enters the service area, the remaining femto station 60 may be shifted to the power saving mode. As a result, the femto station is prevented from shifting from the sleep mode to the power saving mode until the manager is absent due to vacation or lateness. Therefore, further power saving of the wireless communication system 1 is possible.

  Furthermore, even in the same managed mobile station 70, the management femto station 10 may change the date and time when the managed femto station shifts to the power saving mode according to the day of the week, the time zone, and the time. Thereby, the radio | wireless communications system 1 can respond | correspond separately also to the store from which a regular holiday differs in the same shopping mall. Therefore, the femto station installed in the store is prevented from shifting from the sleep mode to the power saving mode until the store is not in operation, and the power consumption of the wireless communication system 1 can be further reduced. It becomes. The monitoring femto stations 20 and 30 are not necessarily installed at the entrance of a facility such as a shopping mall, and may be installed at a specific store or an entrance of each floor. Thereby, detailed power saving according to the area in the facility is realized, and further power saving becomes possible.

  Further, when the femto station adopts two or three small group configurations as in the above embodiment, one femto station (parent femto station) of these femto stations is a management femto station. Of the functions of the monitoring femto station, the monitoring femto station may have at least one function. In this aspect, the parent femto station instructs other femto stations (child femto stations) to shift to or return from each mode. In addition, when all mobile stations are absent from the femto group, the parent femto station shifts the child femto station to the sleep mode, and the parent femto station itself also shifts to the power saving monitoring mode. Stop functions and management functions. Thereby, a radio | wireless communications system can be comprised with fewer femto stations. Therefore, a system with a simple configuration can be realized, and low power consumption, low cost, and space saving can be achieved.

  As yet another aspect, the management function of the management femto station 10 according to the above embodiment may be distributed between the parent femto station and the child femto station. In this mode, for example, when the mobile station moves from one child femto station to the other child femto station, the destination child femto station directly shifts to the power saving mode with respect to the source child femto station. An instruction will be sent. Thereafter, the child femto station of the moving destination notifies the parent femto station having the located state management table 13 of the new mode of the child femto station and the visited state of the mobile station, and the parent femto station Update information. As a result, since the child femto station has a part of the management function, the wireless communication system 1 can distribute the processing load and processing time accompanying the realization of the management function of the parent femto station to the child femto station. it can. As a result, the system load is reduced.

  In the above embodiment, the management function, the monitoring function, the base station function are concentrated on the parent femto station, and on the contrary, the management function is distributed to each femto station. The main body and functions to be distributed are not limited to these modes. FIG. 14 is a diagram illustrating a correspondence F between each femto station and a function according to the embodiment. For example, in the above embodiment, as shown in FIG. 14, only the management femto station 10 has a management function and only the femto stations 40, 50, 60 have a pause function. These functions may be provided to the monitoring femto stations 20 and 30. In the above embodiment, as shown in FIG. 14, the monitoring femto stations 20 and 30 and the femto stations 40, 50, and 60 have both a monitoring function and a base station function. All or part of the functions may be distributed to the management femto stations 10.

  Moreover, in the said Example, since the case where two entrances existed in a shopping mall, the monitoring femto stations 20 and 30 shall be arrange | positioned in the vicinity of each entrance. However, the number of monitoring femto stations installed in a shopping mall is not necessarily one at each entrance, and two or more monitoring femto stations may be installed near one entrance. . This avoids unintended power consumption. That is, when a user who owns a managed mobile station or registered mobile station stops near a shopping mall for a walk or the like, the monitoring femto station detects the user's entry area against the user's intention. May end up. In this case, not only the monitoring femto station, but also the management femto station and the intra-group femto station return to the normal mode with high power consumption, which is not preferable from the viewpoint of power saving. Therefore, the wireless communication system 1 may be configured to arrange two or more monitoring femto stations at different positions near one entrance. According to this aspect, since the mode does not return unless the user detects the presence in two or more monitoring femto stations, the probability that the originally required power saving mode is canceled due to the user's visit. Decrease. Therefore, the concern that unnecessary power is consumed with the unexpected mode transition is solved.

  Further, the wireless communication system 1 may divide and arrange the monitoring femto stations so as to limit the femto stations targeted for mode transition when the area in the monitoring femto station is detected. That is, in the above-described embodiment, when any of the monitoring femto stations 20 and 30 detects the entrance of the management mobile station, the mode of all the femto stations 40, 50, and 60 arranged in the shopping mall is set to the sleep mode. To return to power saving mode. However, the present invention is not limited to this mode, and the pause mode may be canceled only in some femto stations (for example, femto stations 40 and 50) when the managed mobile station enters the service area. As a result, even if unintended location detection occurs due to a user's visit or the like, all femto stations belonging to the femto station group G will not return to the power saving mode. In other words, the number of femto stations that erroneously return to the mode is limited, and the range thereof is limited, so that an increase in power consumption due to erroneous detection is suppressed.

  In the above embodiment, regarding the pseudo-paging, each femto station 40, 50, 60 preferably performs pseudo-paging periodically at the same timing. However, each femto station 40, 50, 60 can perform pseudo-paging without waiting for the elapse of a predetermined period at the timing indicated by the management femto station 10. For example, assume that when the mobile station 80 is located in the femto station 40, the femto station 40 detects the absence of the mobile station 80 by the next pseudo-paging. In this case, since the mobile station 80 may have moved to another femto station other than the femto station 40, the management femto station 10 instructs the other femto stations 50 and 60 to search for the mobile station. . Each femto station 50, 60 executes pseudo-paging immediately or at a given timing according to an instruction from the management femto station 10, and notifies the management femto station 10 of the result. Thereby, the management femto station 10 detects the femto station in which each mobile station 70-100 exists within a desired timing at a desired timing regardless of the elapse of the cycle, and the result is the in-zone state management table. 13 can be reflected. Therefore, the management femto station 10 can reliably and in real time know which femto station each mobile station 70 to 100 is in. Therefore, the management femto station 10 can shift the femto base station that can shift to the power saving mode to the power saving mode without omission because no mobile station is located. As a result, more effective power saving can be achieved without any shortage.

  However, even if the femto stations 40, 50, and 60 perform pseudo-paging, if the mobile station is turned off, the location cannot be detected. Therefore, although the exit from the shopping mall has not been detected yet, the mobile stations that are confirmed to be absent from all the femto stations 40, 50, 60 are turned off. Judgment can be made. Therefore, the management femto station 10 temporarily excludes the mobile station from the target of pseudo paging. Since a mobile station once excluded from the target of pseudo-paging is not considered to be located even if it exists in the area of any femto station, each femto station 40, 50, 60 There is no transmission / reception of radio waves. As a result, the amount of radio wave transmission / reception associated with pseudo-paging decreases. Therefore, each femto station 40, 50, 60 can realize further power saving.

  Thereafter, when the power of the registered mobile station 80 as the mobile station is turned on again in the shopping mall, the registered mobile station 80 executes the ATTACH process. In other words, the registered mobile station 80 detects a femto station (for example, the femto station 60) in the femto station group G, registers the femto station 60 in the network of the femto station via the femto station 60, and performs TA (Tracking) in the group G. Area) number is acquired. The femto station 60 detects that the mobile station 80 is located in its own station by the registration process, and reports the fact to the management femto station 10. After confirming whether or not the mobile station 80 is a registered mobile station, the management femto station 10 registers the mobile station 80 again as a target for pseudo paging. The registration result is notified from the management femto station 10 to each femto station 40, 50, 60, so that each femto station 40, 50, 60 resumes pseudo-paging including the mobile station 80 as a target.

  Moreover, in the said Example, each component of the femto stations 10-60 and the mobile stations 70-100 does not necessarily need to be physically comprised like illustration. That is, the specific mode of distribution / integration of each device is not limited to the illustrated one, and all or a part thereof is functionally or physically distributed in an arbitrary unit according to various loads or usage conditions. -It can also be integrated and configured. For example, the own station mode control unit 12 and the other station mode control unit 14 of the management femto station 10 or the in-zone monitoring unit 44 and the time measuring unit 45 of the femto station 40 may be integrated as one component. On the contrary, the location status management table 13 of the management femto station 10 may be distributed into a part for managing the mode of each femto station and a part for managing the presence / absence of each mobile station. Further, the communication unit 41 of the femto station 40 may be distributed into a part that notifies the management femto station 10 of the presence and absence of the mobile station and a part that receives a mode transition instruction from the management femto station 10. Furthermore, the memories 10b to 60b may be connected as an external device of the femto stations 10 to 60 via a network or a cable.

DESCRIPTION OF SYMBOLS 1 Wireless communication system 10 Management femto station 11 Communication part 12 Own station mode control part 13 Station state management table 14 Other station mode control part 15 Time measuring part 16 Mobile station number determination part 20, 30 Monitoring femto station 21, 31 Communication part 22 , 32 Entrance area monitoring unit 23, 33 Own station mode control unit 40, 50, 60 Femto station 41, 51, 61 Communication unit 42, 52, 62 Own station mode control unit 43, 53, 63 Mobile station type determination unit 44, 54, 64 Area monitoring unit 45, 55, 65 Timekeeping unit 10a, 20a, 30a, 40a, 50a, 60a CPU
10b, 20b, 30b, 40b, 50b, 60b Memory 10c, 20c, 30c, 40c, 50c, 60c RF circuit 10d, 20d, 30d, 40d, 50d, 60d Network IF
70 Management mobile station 70a CPU
70b Memory 70c RF circuit 80, 90, 100 Registered mobile station 80a, 90a, 100a CPU
80b, 90b, 100b Memory 80c, 90c, 100c RF circuit A1, A2 Antenna F Correspondence between each femto station and each function G Femto station group

Claims (5)

A wireless communication system having a management device and a first base station that communicates with the management device,
The management device
Instructing the first base station to switch between the first mode and the second mode, which consumes less power than the first mode, depending on whether there is a mobile station located in the first base station. An indicator,
A first control unit that performs control to shift to the second mode when the mobile station is out of the area managed by the management device;
The first base station is
A wireless communication system, comprising: a second control unit that performs control to shift between the first mode and the second mode based on the instruction.   The instructing unit of the management apparatus instructs the first base station to shift to a third mode that consumes less power than the second mode when the mobile station leaves the area managed by the management apparatus. The wireless communication system according to claim 1, wherein:   The instruction unit of the management device monitors the transition to the second mode when the mobile station leaves the area managed by the management device, and monitors whether the mobile station has entered the area. 3. The wireless communication system according to claim 2, wherein two base stations are instructed. A management device that communicates with a base station,
An instruction unit that instructs the base station to switch between a first mode and a second mode that consumes less power than the first mode, depending on whether there is a mobile station located in the base station,
And a control unit that performs control to shift to the second mode when the mobile station leaves the area managed by the management device. A wireless communication method in a wireless communication system having a management device and a base station that communicates with the management device,
The management device
Instructing the base station to switch between the first mode and the second mode with lower power consumption than the first mode, depending on the presence or absence of a mobile station located in the base station,
When the mobile station is out of range from the area managed by the management device, control to shift to the second mode,
The base station
A wireless communication method, wherein control is performed to shift between the first mode and the second mode based on the instruction.

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