Radio base station program update method and apparatus not requiring update host computer

A program updating apparatus for a radio base station includes a plurality of non-management radio base stations and a management radio base station. Each of the plurality of non-management radio base stations has a first program. The management radio base station stores a second program to which the first program is updated. The management radio base station transmits the second program to at least one of the plurality of non-management radio base stations such that the first program is updated to the second program. The non-management radio base station having the second program, as a first master radio base station, transmits the second program to another of the plurality of non-management radio base stations, as a first slave radio base station, which does not have the second program such that the first program is updated to the second program.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a program updating apparatus for a radio base station and method as the same, which update a program of a radio base station used in a private wireless telephone using a private branch switching unit.

2. Description of the Related Art

New services such as a character communication and the like, are developed one after another, as a PHS (Personal Handy-phone System) service. Usually, an addition of a new service requires a change of a program for a radio base station (CS). Typically, the radio base station is installed at a place, such as a ceiling or the like, which is difficult for a hand to reach, by considering the characteristic of an electrical wave transmission. For this reason, once it is installed, it is difficult to carry out a program change work, such as a change of ROM and the like. So, several program download methods are proposed in order to update a program of a radio base station.

An example of a program download method to a conventional radio base station is disclosed in Japanese Laid Open Patent Application (JP-A-Heisei 7-87543) (a first conventional technique). In this conventional method, in order to carry out a program download at a high speed, a high speed line is installed between the base stations, and a download program is transferred on this high speed line.

Japanese Laid Open Patent Application (JP-A-Heisei 10-40189) (a second conventional technique) discloses a method in which a host computer transfers a download program to a radio base station and then the radio base station sequentially transfers a program to a next radio base station.

The first conventional technique has a problem that when a new program to be downloaded is transferred in a master base station, it requires an external memory as well as a high speed line.

Also, the second conventional technique has the following problem. That is, it requires a host computer. Moreover, a radio base station carrying out the download sequentially downloads a program to a next radio base station. Thus, if there are a large number of radio base stations, a period corresponding to the number is needed.

The present invention is accomplished in view of the above mentioned problems. Therefore, an object of the present invention is to provide a radio base station program download method which can easily update a program for many radio base stations in a short time without requiring a special facility.

The following techniques are disclosed.

Japanese Laid Open Patent Application (JP-A-Heisei 6-105352) discloses a download method to a base station in a mobile switch system, as follows. The mobile switch system containing a plurality of base stations, base station controllers, mobile switches, monitors and control terminals connected to the monitors is used to prepare interface converters in the monitors and the mobile switches for carrying out the relay processes between the control terminals and the base station controllers. Then, an interface switch is carried out in a lower layer. After completion of connection of the lower layer, the control terminal carries out a communication control in a layer. The preparation of the download between the control terminal and the base station controller is checked to then send out a download file from the control terminal.

Japanese Laid Open Patent Application (JP-A-Heisei 10-224286) discloses a method for updating a system file of a mobile communication system and the base stations thereof, as follows. At least one file transfer base station is prepared at each of blocks, each having a plurality of base stations. A system file is transmitted from a maintenance apparatus through a fixing network to each file transfer base station. The file transfer base station receiving the system file sequentially transfers the system file through the fixing network to the other base stations in each block.

Japanese Laid Open Patent Application (JP-A-Heisei 243446) discloses a multi-base station download method, as follows. In a simple type portable telephone system of a multi-base station method, at a time of download, a higher rank apparatus reports a download instruction of a master base station and a slave base station to the master base station. The master base station reports a download start instruction to respective slave base stations. Accordingly, when the master base station and the respective slave base stations establish a download data link between the higher rank apparatus and them and then receive the download data and further validate a reception download data and thereby detect a normal reception, the slave base station reports a download result information to the master base station, and then the master base station reports the end of the downloads of the master base station and the slave base station to the higher rank apparatus. Thus, the downloads become possible in the master base station and the slave base station, respectively, individually and simultaneously.

SUMMARY OF THE INVENTION

The present invention has been made to solve the above-described problems of the conventional program updating apparatus for a radio base station. An object of the present invention is to provide a program updating apparatus for a radio base station which can easily update a program for many radio base station in short time without requiring special facility.

In order to achieve an aspect of the present invention, a program updating apparatus for a radio base station includes a plurality of non-management radio base stations wherein each of the plurality of non-management radio base stations has a first program and a management radio base station storing a second program to which the first program is updated, and wherein the management radio base station transmits the second program to at least one of the plurality of non-management radio base stations such that the first program is updated to the second program, and the non-management radio base station having the second program, as a first master radio base station transmits the second program to another of the plurality of non-management radio base stations as a first slave radio base station which does not have the second program such that the first program is updated to the second program.

In this case, the first slave radio base station receiving the second program from the first master radio base station as a second master radio base station transmits the second program to another of the plurality of non-management radio base stations as a second slave radio base station which does not have the second program.

Also in this case, each of the first and second master radio base station has a master right, and the master right is propagated such that all of the plurality of non-management radio base stations undergoes the master radio base station

Further in this case, at a substantially same time when the first master radio base station transmits the second program to the first slave radio base station the first master radio base station as a second master radio base station transmits the second program to the first slave radio base station as a second slave radio base station

In order to achieve another aspect of the present invention, a program updating apparatus further includes a switching unit to which each of the plurality of non-management radio base stations and the management radio base station are connected, and wherein the switching unit has a management table and refers to the management table to connect each of the plurality of non-management radio base stations and the management radio base station and the management table has a first memory area in which an identification number data assigned to each of the plurality of non-management radio base stations is stored and a second memory area in which a data indicative of a state of each of the plurality of non-management radio base stations is stored, the state data indicating whether or not the non-management radio base station has the second program and whether or not the non-management radio base station is transmitting or receiving the second program, and the switching unit refers to the second memory area to retrieve the state data indicating that the non-management radio base station does not have the second program and the state data indicating that the non-management radio base station has the second program, and selects the master radio base station and the slave radio base station based on the retrieved result to connect the selected the master radio base station to the selected slave radio base station

In this case, an identification number data assigned to the management radio base station is further stored in the first memory area the state data of the management radio base station is further stored in the second memory area and the management table further has a third memory area in which a data is stored, the data being indicative of a communication destination when the second program should be transmitted.

Also in this case, each of the plurality of non-management radio base stations and the management radio base station have a substantially same circuit configuration other than a fact that the second program is stored in the management radio base station in advance.

Further in this case, each of the management radio base station and the plurality of non-management radio base stations further has a mode setting unit setting as a operation mode, any one of a management radio base station mode a master radio base station mode and a slave radio base station mode and wherein the program updating apparatus further has a switching unit to which the each non-management radio base station and the management radio base station are connected, and wherein the mode setting unit of the management radio base station sets to the management radio base station mode in advance to output a first data indicating that the management radio base station is in the management radio base station mode to the switching unit and the switching unit outputs a mode setting signal to designate the master radio base station and the slave radio base station in response to the first data, and the mode setting unit of each non-management radio base station sets to any one of the master radio base station mode and the slave radio base station mode based on the mode setting signal.

In this case, each of the management radio base station and the plurality of non-management radio base stations further has a mode setting unit setting as a operation mode, any one of a management radio base station mode a master radio base station mode and a slave radio base station mode and wherein the program updating apparatus further has a switching unit to which the each non-management radio base station and the management radio base station are connected, and wherein the management radio base station is connected to the switching unit at a predetermined position, the switching unit identifies the management radio base station based on the position, and the switching unit outputs a mode setting signal to designate the master radio base station and the slave radio base station in response to the first data, and the mode setting unit of each non-management radio base station sets to any one of the master radio base station mode and the slave radio base station mode based on the mode setting signal.

Also in this case, the management radio base station further has a report unit reporting that the management radio base station is transmitting the second program and that a transmission of the second program to all of the plurality of non-management radio base stations is completed.

In order to achieve still another aspect of the present invention, a program updating method of a radio base station, includes (a) providing a plurality of non-management radio base stations wherein each of the plurality of non-management radio base stations has a first program, (b) providing a management radio base station storing a second program to which the first program is updated, (c) setting any one of the plurality of non-management radio base stations as an N-th (N is an integer equal to or more than 1) slave radio base station (d) transmitting the second program to the N-th slave radio base station from the management radio base station to update the first program of the N-th slave radio base station to the second program, (e) setting the N-th slave radio base station having the second program as an M-th (M is an integer equal to or more than 1) master radio base station, (f) setting any one of the plurality of non-management radio base stations which does not have the second program, as an (N+1)-th slave radio base station, and (g) transmitting the second program to the (N+1)-th slave radio base station from the M-th master radio base station to update the first program of the (N+1)-th slave radio base station to the second program.

In this case, a program updating method further includes (h) setting the (N+1)-th slave radio base station having the second program as an (M+1)-th master radio base station (i) setting any one of the plurality of non-management radio base stations which does not have the second program as an (N+2)-th slave radio base station and (j) transmitting the second program to the (N+2)-th slave radio base station from the (M+1)-th master radio base station to update the first program of the (N+2)-th slave radio base station to the second program.

Also in this case, a program updating method further includes (k) setting the (N+2)-th slave radio base station as the (N+1)-th slave radio base station and setting the (M+1)-th master radio base station as the M-th master radio base station to repeat the respective steps of (g) to (j) such that all of the plurality of non-management radio base stations have the second program.

Further in this case, a first flow including the steps of (c) and (d), a second flow including the steps of (e) to (g) and a third flow including the steps of (h) to (j) are performed in parallel to each other.

In this case, a program updating method further includes (L) assigning an identification number to each of the plurality of non-management radio base stations and the management radio base station and wherein the (c) step includes setting a non-management radio base station having a lowest identification number of the plurality of non-management radio base stations as the N-th slave radio base station and the (f) step includes setting a non-management radio base station having a lowest identification number of the plurality of non-management radio base stations as the (N+1)-th slave radio base station and the (i) step includes setting a non-management radio base station having a lowest identification number of the plurality of non-management radio base stations as the (N+2)-th slave radio base station

Also in this case, a program updating method further includes (M) providing a management table wherein the management table stores an identification number assigned to each of the plurality of non-management radio base stations and a data indicating whether or not each non-management radio base station has the second program, (N) referring to the management table to generate a referring result, (O) retrieving, based on the referring result, a non-management radio base station having a lowest identification number of the plurality of non-management radio base stations which have the second program, as the master radio base station (P) retrieving, based on the referring result, a non-management radio base station having a lowest identification number of the plurality of non-management radio base stations which do not have the second program, as the slave radio base station and (Q) transmitting the second program to the retrieved slave radio base station from the retrieved master radio base station to update the first program to the second program.

Further in this case, a program updating method further includes (R) reporting a completion of an operation of updating a program when all of the plurality of non-management radio base stations have the second program.

In order to achieve yet still another aspect of the present invention, a program updating method of a radio base station, includes (S) providing a plurality of radio base stations wherein each of the plurality of radio base stations has a first program, (T) providing a second program to which the first program is updated, (U) transmitting the second program to any one of the plurality of radio base stations to update the first program to the second program, and (V) transmitting the second program to one of the plurality of radio base stations which does not have the second program, from the radio base station having the second program, to update the first program to the second program.

In order to achieve another aspect of the present invention, a computer readable recording medium for recording a program for a process includes (a) providing a plurality of non-management radio base stations wherein each of the plurality of non-management radio base stations has a first program, (b) providing a management radio base station storing a second program to which the first program is updated, (c) setting any one of the plurality of non-management radio base stations as an N-th (N is an integer equal to or more than 1) slave radio base station (d) transmitting the second program to the N-th slave radio base station from the management radio base station to update the first program of the N-th slave radio base station to the second program, (e) setting the N-th slave radio base station having the second program as an M-th (M is an integer equal to or more than 1) master radio base station (f) setting any one of the plurality of non-management radio base stations which does not have the second program, as an (N+1)-th slave radio base station and (g) transmitting the second program to the (N+1)-th slave radio base station from the M-th master radio base station to update the first program of the (N+1)-th slave radio base station to the second program.

In this case, a computer readable recording medium further includes (h) setting the (N+1)-th slave radio base station having the second program as an (M+1)-th master radio base station (i) setting any one of the plurality of non-management radio base stations which does not have the second program as an (N+2)-th slave radio base station and (j) transmitting the second program to the (N+2)-th slave radio base station from the (M+1)th master radio base station to update the first program of the (N+2)-th slave radio base station to the second program.

Also in this case, a computer readable recording medium further includes (k) setting the (N+2)-th slave radio base station as the (N+1)-th slave radio base station and setting the (M+1)-th master radio base station as the M-th master radio base station to repeat the respective steps of (g) to (j) such that all of the plurality of non-management radio base stations have the second program.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A. Configuration of Embodiment

FIG. 1is a block diagram showing a whole configuration according to a first embodiment in the present invention. As shown inFIG. 1, this embodiment is provided with a private PHS personal machine (PS)1, a private PHS radio base (cell) station (CS)2, a management radio base station (management CS)3and a private branch exchange (PBX) (switching unit)4which are respectively operated with each program control.

The private PHS personal machine1has a function for carrying out a radio communication with the private PHS radio base station2. The private PHS radio base station2has a function for carrying out a radio communication with the private PHS personal machine1and a communication with the private branch switching unit4. The private branch switching unit4has a switching function and provides a private PHS service as a whole system.

The management radio base station3and the private PHS radio base station2have the same circuit configuration except the difference described later. Here,FIG. 2is a block diagram showing the configuration of the management radio base station3and the private PHS radio base station2.

InFIG. 2, each of the management radio base station3and the private PHS radio base station2has a ROM31, a dip switch32, a lamp33, a RAM34, a line input/output circuit35and a radio input/output circuit36.

Each of the private PHS radio base station2and the management radio base station3is connected to the private branch switching unit4through ISDN (Integrated Service Digital Network) which is a line interface of PHS. The line input/output circuit35controls a control channel351(Dch) and a call channel352(Bch) of an ISDN base interface (2B+D). A program is stored in the ROM31.

The dip switch32is switched to any one of a management CS mode and a normal operation mode to determine an operational state of its radio base station. A reading unit301reads the mode to which the dip switch32is switched, and then outputs the read result to the line input/output circuit35. If the dip switch32is switched to the management CS mode, its radio base station functions as the management radio base station3. If the dip switch32is switched to the normal operation mode, its radio base station functions as the private PHS radio base station2. The radio input/output circuit36controls the radio communication with the private PHS personal machine1. The RAM34transiently stores a program downloaded from the other radio base stations. The RAM34is used to operate a software of a usual PHS base station.

The difference between the private PHS radio base station2and the management radio base station3is as follows. In the management radio base station3, a program (hereafter, referred to as a download program) to be downloaded to all the radio base stations contained in the private branch switching unit4is already written to the ROM31, in a factory for producing a radio base station in advance.

Each of the management radio base station3and the private PHS radio base station2has a mode setting unit300. The mode setting unit300establishes that its radio base station (the intra-office) is operated at any one of the normal operation mode, the management CS mode, a master CS mode and a slave CS mode. The mode setting unit300sets the above-mentioned mode in accordance with the set condition of the dip switch32, or an instruction received through the control channel31from the private branch switching unit4.

In the management CS mode, the reading unit301and a lamp control unit302are started up. The reading unit301identifies the set condition of the dip switch32, and reports a fact that the intra-office (its radio base station) is set as the management radio base station3, through the control channel351to the private branch switching unit4. The lamp control unit302receives a state signal indicative of a state of the intra-office (whether the intra-office is in a state under the download or the download has been completed) through the control channel351from the private branch switching unit4. The lamp control unit302, when receiving the state signal, represents the state indicated by the state signal by using a flash state (pattern) of the lamp33.

In the management CS mode and the master CS mode, a program transfer unit303is started up. The program transfer unit303outputs a download program data stored in the ROM31to the line input/output circuit35, in response to a request from the private branch switching unit4. The download program data outputted to the line input/output circuit35is sent (downloaded) to the other radio base stations through the call channel352and the private branch switching unit4. The program transfer unit303, after the download program data is sent, reports a transfer completion signal indicating the completion of sending (transferring) the data, through the line input/output circuit35, the call channel352and the private branch switching unit4to the other radio base stations.

In the slave CS mode, a program receiving unit304and a rewriting unit305are started up. The program receiving unit304receives the download program data downloaded through the private branch switching unit4and the call channel352. The program receiving unit304stores in the RAM34the received download program data. The rewriting unit305, when receiving the transfer completion signal, rewrites the download program stored in the RAM34, to the ROM31. At this time, its radio base station is started up in accordance with the new (rewritten) program of the ROM31, and reports the starting up in accordance with the new program, through the control channel351to the private branch switching unit4.

FIG. 3is a block diagram showing the circuit configuration of the private branch switching unit4. The private branch switching unit4includes a mode setting unit400, a program transfer unit401, a lamp control unit402, a managing unit403and a CS download management memory41.

The CS download management memory41stores therein the data to carry out this download as well as the data to carry out the usual switching function including the PHS. The mode setting unit400indicates an operation mode to the radio base station. The program transfer unit401connects the management radio base station3and the private PHS radio base station2to each other, or a master CS and a slave CS to each other, through the call channel352, and then transfers a program. The lamp control unit402instructs the management radio base station3or the master CS to turn on and off the lamp.

The managing unit403manages and identifies the respective radio base stations in the CS download management memory41by using a CS number (identifier) and always checks the states of the respective radio base stations. The managing unit403updates the data to indicate the write states of the respective radio base stations, in the CS download management memory41. Accordingly, the managing unit403enables the slave CS to which the program is rewritten, to function as the master CS. The managing unit403can complete the download to all the radio base stations in a short time by instructing and managing the download between the plurality of radio base stations.

The management memory41has a plurality of first memory areas41A, a plurality of second memory areas41B and a plurality of third memory areas41C. The first memory area41A stores therein a CS number given to each of all the private PHS radio base stations2and the management radio base stations3connected to the private branch switching unit4. The CS number is the number used in the private branch switching unit4in order that the private branch switching unit4specifies the radio base station.

Each of the second memory area41B and the third memory area41C is provided so as to correspond to the first memory area41A. The second memory area41B stores the data indicative of a write state of the download program data of the radio base stations2,3corresponding to the CS number. As the write state, there are three states of a not-yet-written state, a in-writing state and an completion of writing state. The third memory area41C stores a CS number of a partner (connection destination) to which a write operation is applied, when the radio base stations2,3corresponding to the CS number are in writing (under the write operation).

B. Operation of Embodiment

The operations of this embodiment will be described below in detail.

At first, an actual work carried out by a maintenance man is described. A maintenance man of a PBX system selects a radio base station in which a download program is written in advance to its ROM31in a CS producing factory or the like. A dip switch32of the selected radio base station is set to the management CS mode. The radio base station set to the management CS mode is connected to the private branch switching unit4as the management radio base station3. At this time, it is desirable that the management radio base station3is installed in a management room of the private branch switching unit4because the installation is easy and the lamp is visible.

The lamp33indicative of the operation mode and the transmission state is mounted in the radio base station, as shown inFIG. 2. After the management radio base station3is connected to the private branch switching unit4, the management radio base station3starts the flash of the lamp33, in order to represent the management radio base station3is in the in-writing state. This flash pattern is a pattern evidently different from the normal operation state so that it can be evidently recognized by the maintenance man.

After the completion of the downloads to all the radio base stations, the lamp33of the management radio base station3carries out a flash operation at another different pattern. Since this flash pattern is checked by the maintenance man, it is recognized that the downloads are completed for all the radio base stations. Accordingly, the management radio base station3is removed to then complete the download work.

The operations of the radio base station (management radio base station3) set to the management CS mode will be described below with reference toFIG. 3.

The radio base station in which the download program is written in advance to the ROM31in a producing factory is turned on and started up by the connection to the private branch switching unit4. The reading unit301of the radio base station reads a state of the dip switch32. The mode setting unit300identifies an operation mode of the radio base station, in accordance with the read result of the reading unit301(Steps A1and A2ofFIG. 5). As the identified result, if the radio base station is not set to the management CS mode, it is operated as the normal operation mode, namely, as the private PHS radio base station2(Step A3ofFIG. 5).

On the other hand, if the radio base station is set to the management CS mode, it is operated as the management radio base station3, as follows. The mode setting unit300reports the fact that the intra-office (its radio base station) is started up as the management radio base station3(a starting up report signal of the management radio base station) to the private branch switching unit4through the line input/output circuit35, by using the control channel351(Step A4ofFIG. 5). The lamp control unit302turns on and off the lamp33at a flash pattern indicative of the start of the in-writing (download) state (Step A5ofFIG. 5).

Next, the radio base station becomes at a state of waiting for an instruction from the private branch switching unit4through the control channel351(Step A6ofFIG. 5). If an instruction (download completion lamp control signal) indicative of a control of a download completion lamp outputted from the private branch switching unit4is received through the control channel351, the lamp control unit302turns on and off the lamp33at a flash pattern indicative of the completion of all the downloads (Steps A7and A8ofFIG. 5).

If an instruction of starting a transfer of the download program outputted from the private branch switching unit4is received through the control channel351, the program transfer unit303starts the transfer of the download program stored the ROM31, to the slave CS through the private branch switching unit4by using the call channel352(Steps A9and A10). The reason why it is transferred by using the call channel352is that it can be transferred faster than the control channel351.

The management radio base station3, when completing the transfer of all of the download program, outputs the transfer completion signal through the call channel352to the private branch switching unit4. The management radio base station3becomes at a state of waiting for the instruction from the private branch switching unit4in the line input/output circuit35through the control channel351(Steps A11and A12ofFIG. 5). The management radio base station3, if again receiving the instruction of starting transferring the program (Step A9—YES), executes the operations on and after the step A10. On the other hand, the management radio base station3, if receiving the download completion lamp control signal (Step A7—YES), executes the operations on and after the step A8.

The operations of the radio base station (slave CS) set to the slave CS mode will be described below with reference toFIG. 6. The private PHS radio base station2receives an instruction of setting to the slave CS mode (a slave CS set signal) through the control channel351from the private branch switching unit4by using the line input/output circuit35(Step B1ofFIG. 6). The private PHS radio base station2, if receiving the slave CS set signal, uses the mode setting unit300to then set the intra-office (the private PHS radio base station2, itself) to the slave CS mode, and also transmits a slave set report signal through the control channel351to the private branch switching unit4(Step B2ofFIG. 6). Accordingly, the private PHS radio base station2(slave CS) set to the slave CS becomes at a state of waiting for a reception of the download program.

The program receiving unit304of the slave CS receives the download program data through the call channel352, and then stores it in the RAM34(Step B3). The slave CS, if receiving the transfer completion signal, uses the rewriting unit305to then write the data stored in the RAM34to the ROM31(Steps B4and B5). If the rewrite of the ROM31is completed, the slave CS is started up in accordance with its new program (re-starting up). The slave CS outputs a signal indicative of the starting up (a rewrite completion signal of the ROM31) from the line input/output circuit35through the control channel351to the private branch switching unit4, on the basis of the new program (Steps B6and B7ofFIG. 6).

The operations of the radio base station (master CS) set to the master CS mode will be described below with reference toFIG. 7. The private PHS radio base station2receives an instruction of setting to a master CS (a master CS set signal) through the control channel351from the private branch switching unit4by using the line input/output circuit35(Step C1ofFIG. 7). At this time, the private PHS radio base station2, if receiving the master CS set signal, uses the mode setting unit300to then set the intra-office to the master CS mode, and also outputs a master set completion signal through the control channel351to the private branch switching unit4(Step C2ofFIG. 7).

The private PHS radio base station2(master CS) receives a instruction of starting the transfer of the program through the control channel351from the line input/output circuit35(Step C3—YES). At this time, the master CS uses the program transfer unit303to then transfer the download program stored in the ROM31of the intra-office through the call channel352and the private branch switching unit4to the slave CS by using the line input/output circuit35(Step C4).

The master CS, if the transfer of all the download program is completed, reports the transfer completion signal through the call channel352by using the line input/output circuit35. Then, the master CS becomes at a state of waiting for the instruction from the private branch switching unit4transmitted through the control channel351, in the line input/output circuit35(Steps C5and C6).

The operations of the private branch switching unit4will be described below with reference toFIGS. 8 to 11. The private branch switching unit4receives a management CS starting up report (a management radio base station starting up report signal, and refer to the step A4ofFIG. 5) outputted from the management radio base station3(Step D1ofFIG. 8). At this time, the private branch switching unit4recognizes that a CS download is started, in accordance with the received signal.

The private branch switching unit4stores a data indicative of the in-writing state in the second memory area41B corresponding to the management radio base station3, in the CS download management memory41. The private branch switching unit4stores a data indicative of the not-yet-written state in the second memory area41B of all the private PHS radio base stations2other than the management radio base station3, in the CS download management memory41(Step D2).

Next, the private branch switching unit4retrieves the CS download management-memory41, and detects the private PHS radio base station2of the not-yet-written state. The mode setting unit400of the private branch switching unit4transmits a slave mode set instruction to the detected private PHS radio base station2through the control channel351(refer to the step D3ofFIG. 8, and the step B1ofFIG. 6). Accordingly, all the private PHS radio base stations2other than the management radio base station3become the slave CS.

The private branch switching unit4receives the slave set report signal through the control channel351from the slave CS (Step D4ofFIG. 8, and Step B2ofFIG. 6). At this time, the private branch switching unit4stores the data indicative of the in-writing state in the second memory area41B of the private PHS radio base station2corresponding to the received slave set report signal, in the CS download management memory41(Step D5ofFIG. 8). The private branch switching unit4connects the call channel352of the management radio base station3to one of the slave CS (Step D6ofFIG. 8), and then sets a CS number of a connection destination for the third memory area41C of the CS download management memory41(Step D7ofFIG. 8).

Next, the private branch switching unit4sends the instruction of starting the transfer of the download program through the control channel351to the management radio base station3(Step D8ofFIG. 8, and Step A9ofFIG. 5). Accordingly, the download (transferring) of the download program is started between the management radio base station3and the slave CS.

Next, the private branch switching unit4receives a rewrite completion signal from the slave CS through the control channel351(Step D9ofFIG. 8). At this time, the private branch switching unit4refers to the CS download management memory41to then disconnect the connection of the call channel352between the slave CS corresponding to the received rewrite completion signal and the management radio base station3(Step D10). The private branch switching unit4rewrites the data of each second memory area41B of the slave CS corresponding to the received rewrite completion signal and the management radio base station3, into the data indicative of the completion of writing state (Step D11ofFIG. 9).

Next, the private branch switching unit4uses the managing unit403to then retrieve the CS download management memory41and further detect the private PHS radio base station2in which the data of the second memory area41B is at the not-yet-written state (Step D12).

As the detected result, the absence of the private PHS radio base station2at the not-yet-written state implies the completion of the downloads to all the private PHS radio base stations2. Thus, in this case, the private branch switching unit4uses the mode setting unit400to then transmit an instruction indicative of the starting up at the normal mode through the control channel351to all the private PHS radio base stations2except the management radio base station3(Step D13).

The private branch switching unit4, if receiving a normal mode set completion report from all the instructed private PHS radio base stations2(Step D14—YES), uses the lamp control unit402to then transmit the download completion lamp control signal through the control channel351to the management radio base station3, and completes the download process (Step D15ofFIG. 10, and Steps A7and A8ofFIG. 5).

At the steps D12and D16ofFIG. 9, although there is the private PHS radio base station2in which the write state is the not-yet-written state (Step D12—YES), if there is not the private PHS radio base station2at the completion of writing state (Step D16—NO), the private branch switching unit4continues the retrieval until the detection of the private PHS radio base station2at the completion of writing state.

The private branch switching unit4, if the private PHS radio base station2at the completion of writing state is detected (Step D16—YES), converts the data in the second memory areas41B of the private PHS radio base station2at the completion of writing state and the private PHS radio base station2at the not-yet-written state (Step D12—YES) into the data at the in-writing state, in the CS download management memory41(Step D17).

The private branch switching unit4assigns a master mode through the control channel351to the private PHS radio base station2at the completion of writing state, and assigns a slave mode to the private PHS radio base station2at the not-yet-written state (Step D18ofFIG. 9, Step B1ofFIG. 6and Step C1ofFIG. 7).

The private branch switching unit4, if receiving from both the master CS and the slave CS the respective mode set completion reports through the control channel351(Step D19—YES, Step B2ofFIG. 6and Step C2ofFIG. 7), connects the master CS and the slave CS to each other through the call channel352(Step D20ofFIG. 9). The private branch switching unit4sets the CS numbers of the mutual connection destinations in the third memory areas41C corresponding to the master CS and the slave CS connected to each other, in the CS download management memory41(Step D21ofFIG. 9).

Next, the private branch switching unit4sends the instruction of starting the transfer of the program through the control channel351to the master CS (refer to Step C3ofFIG. 7), and then returns back to the step S12ofFIG. 9(Step D22ofFIG. 9).

Accordingly, after the download of the program is started between the master CS and the slave CS, the download can be executed between further different radio base stations in parallel. The private branch switching unit4, if receiving the write completion report through the control channel351from the slave CS (Step D23ofFIG. 11, and Step B7ofFIG. 6), refers to the CS download management memory41, and then disconnect the connection of the call channel352between the master CS and the slave CS (Step D24ofFIG. 11). The private branch switching unit4rewrites the data in the second memory area41B of the slave CS and the master CS in the CS download management memory41, into the completion of writing state, and then returns to the step D12ofFIG. 9(Step D25ofFIG. 11).

This results in the increase of the number of the radio base stations at the completion of writing state. Thus, it can proceed to the step D17ofFIG. 9, if the private PHS radio base station2at the completion of writing state is retrieved at the steps D12, D16ofFIG. 9.

A second embodiment of the present invention will be described below with reference toFIGS. 12 to 15.FIG. 12is a block diagram showing a circuit configuration of a radio base station in the second embodiment. As shown inFIG. 12, the radio base station does not have a dip switch32and a reading unit31, differently from the first embodiment shown inFIG. 2. That is, in the radio base station according to the second embodiment, a new program to be downloaded is written in advance to a ROM31, in a management radio base station3, similarly to the first embodiment. However, the management radio base station3of the second embodiment does not have a unit for reporting to a private branch switching unit4a fact that the intra-office (its radio base station) is the management radio base station3. Also, the private branch switching unit4does not have a unit for recognizing the start of the CS download program by receiving the management CS starting up report from the management radio base station3(refer to Step A4ofFIG. 5).

FIG. 13is a block diagram showing the circuit configuration of the private branch switching unit4according to the second embodiment. As shown inFIG. 13, the private branch switching unit4has a management CS discriminating unit404. The management CS discriminating unit404identifies an accommodation position of a radio base station to thereby specify whether the radio base station is the private PHS radio base station2or the management radio base station3. The management CS discriminating unit404determines in advance that, for example, the lowest CS number of the private branch switching unit4is the management radio base station3.

The operations of the radio base station will be described below with reference toFIG. 14. If the radio base station is connected to the private branch switching unit4, it is turned on and started up. Then, it receives an operation instruction at the management CS mode from the private branch switching unit4through the control channel351by using the line input/output circuit35(Step E1ofFIG. 14). Accordingly, the radio base station functions as the management radio base station3. The operations on and after this step are perfectly identical to the above-mentioned operations of the management radio base station3according to the first embodiment, namely, those on and after the step A4ofFIG. 5. Thus, their explanations are omitted.

The operations of the private branch switching unit4will be described below with reference toFIG. 15. The private branch switching unit4, when using the management CS discriminating unit404to then detect the starting up of the radio base station (Step F1ofFIG. 15), judges whether or not it is the management radio base station3, on the basis of an accommodation position of the radio base station (Step F2). The private branch switching unit4, if judging that it is the management radio base station3as the judged result, transmits an instruction indicative of the operation as the management radio base station3through the control channel351to the management radio base station3(Step F3ofFIG. 15). The operations on and after this step are perfectly identical to the above-mentioned operations of the private branch switching unit4according to the first embodiment, namely, those on and after the step D1ofFIG. 5. Thus, their explanations are omitted. Incidentally, the operations of the master CS and the slave CS are perfectly identical to the above-mentioned operations ofFIGS. 6 and 7according to the first embodiment.

As mentioned above, according to the present invention, in order to rewrite the program of the radio base station, it is enough to connect the management radio base station to the private branch switching unit. Thus, it is possible to obtain a merit that a specially managing apparatus is not necessary. Also, according to the present invention, since the radio base station receiving a new program sequentially functions as a master radio base station and then downloads to a non-updated radio base station, a plurality of downloads proceed at the same time. Therefore, it is possible to obtain a merit that the download programs can be completed in a short time, in a large number of radio base stations.