JP3516947B2 - Mobile station - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile station composed of a plurality of mobile stations and performing digital mobile communication between mobile stations using a time division wireless communication system.

[0002]

2. Description of the Related Art Conventionally, in a digital mobile communication system including a base station connected to an exchange through a line and a plurality of radio mobile stations, a TDMA (Time Division)
It is known that a time division wireless communication system such as a multiple access / TDD (Time Division Duplex) system is adopted.

In the TDMA / TDD system, as shown in FIG. 9 which is an explanatory view of the present invention, for example, four time slots T1 to T4 and the same number of time slots R1 to R4 form one frame, In this method, slots T1 and R1, T2 and R2, T3 and R3, and T4 and R4 are used in pairs to realize communication by quad multiplexing. In such a system, transmission and reception are performed separately in time with the transmission slot (T) and the reception slot (R).
The transmission frequency and the reception frequency can be the same frequency, and the frequencies can be effectively used.

Patent Document 1 discloses a digital mobile radio communication system using the TDMA / TDD system.
A configuration is disclosed in which mobile stations can directly communicate with each other. In this configuration, the mobile station has two modes, a master mode and a slave mode. When the mobile station is in the master mode, it determines the communication slot at its own timing, while in the slave mode, it moves in the master mode. By synchronizing with the signal transmitted by the station, communication between mobile stations can be realized without passing through the base station. At this time,
By continuing to use the communication slot of the base station-mobile station which is already in communication and using it for the mobile station-mobile station communication, it is possible to prevent the communication from being disabled for the time required to judge the availability of the slot.

[0005]

[Patent Document 1] JP-A-8-251653

[0006]

However, in the digital mobile radio communication system in the above-mentioned Patent Document 1, in an environment where there is no base station, the mobile station in the master mode is a slave until one communication is completed. Cannot switch to mode. That is, the mobile station once in the master mode must continue to send out the synchronization radio wave for defining the frame timing until the end of the communication. Therefore, there is a problem that the load is concentrated only on the mobile station in the master mode, such as battery consumption due to emission of the synchronization radio wave.

The present invention has been made to solve the above-mentioned conventional problems, and an object of the present invention is to provide all mobile stations that perform communication by providing means for switching the clock master at a predetermined timing. It is to provide a mobile station capable of distributing the load.

[0008]

There are three ways of thinking about how to switch the clock master. That is, the first idea is, as described in claim 1, that the current clock master issues a switching request to all the mobile stations in the slave mode before the current clock master switches to the slave mode, Among all mobile stations, the slave mode mobile station that responds first to the current clock master becomes the next clock master.

Further, the switching request from the current clock master is (claim 2) when the current clock master stops holding transmission data, (claim 3) after the current clock master emits a radio wave for synchronization. (Claim 4) When the current clock master relays data from the mobile station in slave mode for a certain time, (Claim 5) The current clock master transmits a certain amount of data from the mobile station in slave mode When relaying, (Claim 6), when it is detected that the current clock master does not relay data for a certain period of time (Claim 7), when it is determined that the ability of the current clock master as a clock master has deteriorated, (Claim 8)
This is preferably performed at the time when the current clock master detects the interference or (Claim 9) the mobile station in the current slave mode detects the interference of the current clock master.

Here, in claim 7, the clock master having the lowered capability includes the following seven states. (1) When the capability of the clock master is represented by the high performance of the CPU mounted on the clock master, the C required for operating as the clock master
A clock master with lower CPU performance than PU performance. (2) A clock master having a free memory capacity smaller than the free memory capacity required to operate as the clock master when the capacity as the clock master is represented by the free capacity of the memory mounted on the clock master. (3) A clock master having a remaining battery capacity that is smaller than the remaining battery capacity required to operate as the clock master when the ability as the clock master is represented by the remaining capacity of the built-in battery mounted in the clock master. (4) When the capability as a clock master is represented by the electric field strength received from a mobile station in slave mode, the electric field strength received from all mobile stations in slave mode is higher than the electric field strength required to operate as a clock master. A clock master that has at least one of its strengths reduced. (5) When the capability as a clock master is expressed by the error occurrence rate of the received data from the mobile station in slave mode, the error occurrence rate from all the mobile stations in slave mode is higher than the error occurrence rate at which the mobile station can operate as a clock master. A clock master with at least one of the rates increased. (6) When the capability as a clock master is represented by the propagation delay time of the received data from the mobile station in slave mode, the propagation delay from all the mobile stations in slave mode is longer than the propagation delay time that can operate as a clock master. A clock master that has grown at least one of the times. (7) When the ability as a clock master is represented by the number of retransmission request times of the received data from the mobile station in the slave mode, the retransmission request from all the mobile stations in the slave mode is higher than the number of retransmission request times operable as the clock master. A clock master that has increased at least one of the numbers.

The response of the mobile station in the slave mode to the switching request from the current clock master is (claim 10): the mobile station having the best capability as the clock master among all the mobile stations in the slave mode. Item 11) A mobile station that has the best transmission / reception state with other mobile stations among all mobile stations in slave mode, or (claim 12) Minimizes environmental changes due to switching of clock masters among all mobile stations in slave mode. It is preferable that all the mobile stations in slave mode are assigned serial numbers, and are sequentially performed according to the numbers.

A second way of thinking of the switching of the clock master is, as described in claim 14, a mobile station in a slave mode, in which the clock master should become the next clock master before the own station switches to the slave mode. The mobile station in the slave mode, which has been nominated, becomes the next clock master.

The designation of the next clock master is carried out by selecting the mobile station having the best clock master ability among all the mobile stations in the slave mode (claim 15) and the mobile station in the slave mode (claim 16). Then, the mobile station that has the best transmission / reception state with other mobile stations, or (Claim 17) is the mobile station that has the smallest environmental change due to the clock master switching among all the mobile stations in the slave mode, or (Claim 18) It is desirable that serial numbers are assigned to all mobile stations in the slave mode so that they are sequentially performed according to the numbers.

Here, in claim 10 or 15, the mobile station having the best capability as a clock master includes the following three states. (1) A mobile station having the maximum CPU performance among all the mobile stations in the slave mode when the capability of the mobile station is represented by the high performance of the CPU mounted in the mobile station. (2) A mobile station having the maximum free memory capacity among all the mobile stations in the slave mode when the capacity of the mobile station is represented by the free capacity of the memory mounted in the mobile station. (3) A mobile station having the maximum remaining battery capacity among all the mobile stations in the slave mode when the capacity of the mobile station is represented by the remaining capacity of the built-in battery mounted in the mobile station.

In the eleventh or sixteenth aspect, the mobile station having the best transmission / reception state with other mobile stations includes the following eight states. (1) A mobile station having the smallest total deviation value among all the mobile stations in the slave mode when the transmission / reception state is represented by a total value of deviations of received electric field strengths from one mobile station to another mobile station. . (2) When the transmission / reception state is represented by the total deviation of the error occurrence rates of the reception data from one mobile station to another mobile station, the minimum deviation total value among all the mobile stations in the slave mode is calculated. Having a mobile station. (3) When the transmission / reception state is represented by the total value of the deviations of the propagation delay times of the received data from one mobile station to the other mobile station, the minimum total deviation value among all the mobile stations in the slave mode is calculated. Having a mobile station. (4) The mobile station having the best transmission / reception status with the other mobile station means that the transmission / reception status is represented by a total value of deviations of the number of retransmission request times of reception data from one mobile station to another mobile station. A mobile station having the smallest total deviation value among all the mobile stations in the slave mode. (5) A mobile station having the maximum total value of all the mobile stations in the slave mode when the transmission / reception state is represented by the total value of the received electric field strengths from one mobile station to another mobile station. (6) When the transmission / reception state is represented by a total value of error occurrence rates of received data from one mobile station to another mobile station, the mobile station has the smallest total value among all the mobile stations in the slave mode. . (7) When the transmission / reception state is represented by the total value of the propagation delay times of the received data from one mobile station to another mobile station, the mobile station has the smallest total value among all the mobile stations in the slave mode. . (8) A mobile station having the smallest total value among all the mobile stations in the slave mode when the transmission / reception state is represented by the total number of retransmission request times of reception data from one mobile station to another mobile station. .

Further, in the twelfth or seventeenth aspect, the mobile station having the smallest environmental change due to the switching of the clock master includes the following four states. (1) When the environmental change is represented by the received electric field strength from the slave mode mobile station with respect to the received radio wave from the current clock master, the electric field strength with respect to the current clock master is the maximum among all the mobile stations in the slave mode. Station. (2) When the environmental change is represented by the error occurrence rate of the received data from the slave mode mobile station with respect to the received radio wave from the current clock master, the error occurrence rate of the current clock master among all the slave mode mobile stations. Is the smallest mobile station. (3) Propagation delay time for the current clock master among all the mobile stations in the slave mode, when the environmental change is represented by the propagation delay time for the received data from the slave mode mobile station with respect to the received radio wave from the current clock master. Is the smallest mobile station. (4) When the environmental change is represented by the number of retransmission requests of the received data from the slave mode mobile station with respect to the radio wave received from the current clock master, the number of retransmission requests to the current clock master among all the mobile stations in the slave mode. Is the smallest mobile station.

A third way of thinking of switching the clock master is as described in claim 19, in which the mobile station in the slave mode makes a switching request to the current clock master, and the slave mode in which the request is made is made. The mobile station is the next clock master.

The switching request to the current clock master is (claim 20) when a mobile station having a capability superior to that of the current clock master is detected among all mobile stations in slave mode, or (claim 21). It is performed at the time when a mobile station whose transmission / reception state with other mobile stations is superior to the current clock master among all mobile stations in slave mode is detected, or (claim 22) The serial number is sequentially given according to the number, or (Claim 23) When the mobile stations in the two slave modes try to communicate with each other, the above-mentioned 2 obtained through the current clock master. When the transmission / reception state obtained when directly communicating between two mobile stations is better than the transmission / reception state between two mobile stations,
It is desirable to be performed by either one of the above two mobile stations.

Here, in claim 20, the mobile station having a capability superior to that of the current clock master means the following 3
There are two states. (1) A mobile station having higher CPU performance than the current clock master when the capability of the mobile station is represented by the high performance of the CPU installed in the mobile station. (2) A mobile station having a free memory capacity larger than that of the current clock master when the capacity of the mobile station is represented by the free capacity of the memory mounted in the mobile station. (3) A mobile station having a remaining battery capacity higher than that of the current clock master when the capacity of the mobile station is expressed by the remaining capacity of the built-in battery mounted in the mobile station.

Further, in claim 21, the mobile station having a transmission / reception state with another mobile station superior to that of the current clock master includes the following eight states. (1) A mobile station having a total deviation of reception field strength smaller than that of the current clock master when the transmission / reception state is represented by a total deviation of reception field strength from one mobile station to another mobile station. (2) When the transmission / reception state is represented by a total value of deviations of error occurrence rates of received data from one mobile station to another mobile station, the mobile station has a deviation total value of error occurrence rates smaller than that of the current clock master. Station. (3) When the transmission / reception state is represented by the total value of the deviations of the propagation delay times of the received data from one mobile station to the other mobile station, the mobile station has a total deviation value of the propagation delay times smaller than that of the current clock master. Station. (4) When the transmission / reception state is represented by the total value of the deviations of the number of retransmission requests of the received data from one mobile station to another mobile station, the mobile having a deviation total value of the number of retransmission requests smaller than that of the current clock master. Station. (5) A mobile station having a total received field strength higher than that of the current clock master when the transmission / reception state is represented by the total received field strength from one mobile station to another mobile station. (6) A mobile station in which the current clock master also has a small total error occurrence rate when the transmission / reception state is represented by the total error occurrence rate of received data from one mobile station to another mobile station. (7) A mobile station having a total value of propagation delay times smaller than that of the current clock master when the transmission / reception state is represented by the total value of propagation delay times of received data from one mobile station to another mobile station. (8) A mobile station having a total number of retransmission requests smaller than that of the current clock master when the transmission / reception state is represented by the total number of retransmission request times of received data from one mobile station to another mobile station.

Further, in claim 23, the good transmission / reception state includes the following four states. (1) A state in which the electric field strength between only two mobile stations is larger than the average value of the electric field strengths between the current clock master and the two mobile stations. (2) The error occurrence rate obtained when the two mobile stations directly communicate with each other is smaller than the error occurrence rate of the received data between the two mobile stations obtained via the current clock master. (3) The propagation delay time obtained when the two mobile stations directly communicate with each other is smaller than the propagation delay time of the received data between the two mobile stations obtained via the current clock master. (4) The number of retransmission request times obtained when the two mobile stations are directly communicated is smaller than the number of retransmission request times of the reception data between the two mobile stations obtained via the current clock master.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiment 1 The following will describe Embodiment 1 of the present invention with reference to FIGS. 1 to 20, 24, and 25.

As shown in FIG. 2, the time division digital mobile radio communication system is composed of, for example, four mobile stations 1 to 4 which are digital mobile radio communication terminals.
In the figure, for simplification, the digital mobile radio communication system is assumed to be composed of four mobile stations 1 to 4, but the number of mobile stations may be any number.

Each of the mobile stations 1 to 4 has two operation modes, a master mode and a slave mode. When the mobile station is in the master mode, the frame timing is specified by its own timing, and the radio wave for synchronization (synchronization signal) is emitted, while in the slave mode, the frame is synchronized with the radio wave for synchronization transmitted by the mobile station in the master mode. To do. still,
Hereinafter, the mobile station in the master mode will be referred to as a clock master.

Each of the mobile stations 1 to 4 has the structure shown in FIG. That is, each mobile station 1 to 4 has an antenna 1
1, RF (Radio Frequency) unit 12, modem unit 13, T
A DMA / TDD processing unit 14, a voice processing unit 15, a speaker 16, a microphone 17, a control unit (to slave switching requesting means, next master candidacy means, next master nominating means, to master switching requesting means) 18, and an operating unit 19. Each has.

The TDMA / TDD processing unit 14 uses the TDMA
/ For TDD system wireless access,
Set the time slot for sending and receiving. As shown in FIG. 9, one frame consists of 8 slots, the first 4 slots are slots T, and the latter 4 slots are slots R.
And Here, the mobile station transmits data using slot T when it is a clock master and receives it using slot R, while it transmits data using slot R when it is a slave mode mobile station, It is assumed that the slot T is used for reception.

As shown in FIG. 1, the control unit 18 receives various key inputs from the keyboard 19a of the operation unit 19 at the time of calling or receiving a call, and forms various command signals to be sent to the other party of transmission and reception. At this time, the command and the like are displayed on the display 19b of the operation unit 19.

When the communication state is established, the control unit 18 controls the RF unit 12, the modem unit 13, the TDMA / TDD processing unit 14, and the voice processing unit 15 in synchronization with the set transmission / reception time slot. . As a result, the audio signal from the microphone 17 processed by the audio codec 15a of the audio processing unit 15 is transferred to the TDMA / TDD processing unit 14, modulated by the modulation unit 13b in the modem unit 13, and R
It is transmitted to another mobile station (hereinafter referred to as another station) via the F section 12 and the antenna 11 during the transmission slot period. On the other hand, the signal transmitted from the other station in the reception slot period is received through the antenna 11 and the RF unit 12, demodulated by the demodulation unit 13a in the modem unit 13, and transmitted through the TDMA / TDD processing unit 14 and the voice codec 15a. The audio signal is reproduced as an audio signal and supplied to the speaker 16.

Here, the control unit 18 performs the switching process of the clock master, which is a feature of the present invention, the reception level detection unit 21, the error detection unit 22, the propagation delay time measurement unit 23, the synchronization signal detection unit. 24, built-in timer 25, battery capacity monitoring unit 26, CPU monitoring unit 27, ROM (Read On
ly Memory) 28, CPU (Central Processing Unit) 2
9 and a RAM (Random Access Memory) 30.

The reception level detector 21 is for detecting the electric field strength of the reception data transmitted from another station.

The error detector 22 is for detecting an error in the received data transmitted from another station.

The propagation delay time measuring section 23 is for measuring the difference between the time when another station transmits data and the time when the local station receives the data, that is, the propagation delay time.

The sync signal detector 24 is for detecting the sync radio wave emitted by the clock master.

The built-in timer 25 sets the world standard time at 0: 0.
It is manufactured so that 0 is counted up as 0.

The battery capacity monitor 26 is for monitoring the capacity of the built-in battery mounted in the mobile station.

The CPU monitoring section 27 is for monitoring the high performance of the CPU 29.

The ROM 28 stores the synchronization radio wave emission interval A1 and the data relayable time A, which are the control values shown in FIG.
3, data non-transmission confirmation time A4, CPU performance monitoring time A5, reception error measurement interval A7, measurement data emission interval A9, clock master switching interval A10, relayable data amount A11, and retransmission request number measurement interval A12,
CPU performance limit C1, free memory capacity limit C2, battery remaining capacity limit C3, electric field strength limit C4, reception error rate limit C5, and propagation delay limit C shown in FIG.
6, and an area for the retransmission request count limit value C7 is provided. These control values are set at the time of manufacture and have a structure that cannot be changed by the user.

The synchronization radio wave emission interval A1 is set to an interval at which the synchronization radio wave is emitted. Further, the data relayable time A3, the data non-transmission confirmation time A4, the clock master switching interval A10, and the relayable data amount A11 are each set to an appropriate time / interval / amount. The CPU performance monitoring time A5, the reception error measurement interval A7, and the retransmission request count measurement interval A12 are set to intervals necessary for measuring the CPU performance value, the reception error rate, and the retransmission request count described later. The measurement data emission interval A9 is set to an interval for emitting the control data D17 (see FIG. 8G) of the inspection data emission request, which will be described later, for measuring the transmission / reception state with other stations.

The CPU performance limit value C1, free memory capacity limit value C2, battery remaining capacity limit value C3, and electric field strength limit value C4 are the CPU performance, free memory capacity, and battery required to operate as a clock master, respectively. Set the remaining capacity and the limit value of the electric field strength. Also, the reception error rate limit value C5 and the propagation delay limit value C
6 and the retransmission request count limit value C7 are set to the reception error rate, the propagation delay time, and the retransmission request count limit value operable as a clock master.

In the RAM 30, the CPU performance table B1, free memory capacity table B2, remaining battery capacity table B3, and a plurality of electric field strength tables B of the same number as the maximum mobile station number shown in FIG.
4, a plurality of reception error rate tables B5, a plurality of propagation delay time tables B6, and a plurality of retransmission request number tables B7, and P shown in FIG.
There is an area for storing a correspondence table of S-ID (Personal Station-Identification) and mobile station numbers.
The numerical values in these tables can be freely read and written by the CPU 29.

The PS-ID is a second-generation cordless telephone system standard (R
CR STD-28), ROM 28 at the time of shipment
Is written in. The mobile station numbers “1” for the clock master and N (three in the present embodiment) slave mode mobile stations correspond to the PS-IDs of “2” to “N + 1” for each mobile station. Have been assigned.

Here, the maximum value of the mobile station number is "25".
4 ", and the maximum number of 254 existing in the network
It is possible to support individual mobile stations. Therefore, at this time, the number of each of the tables B4 to B7 is 254.

The CPU 29 controls the respective units in the control unit 18 to issue a clock master switching instruction.

7 and 8, the communication data D1, control data D2 to D6, and control data D1 in the control unit 18 are shown.
The formats of 1 to D21 are shown.

As shown in FIG. 7A, these communication /
The control data is 20 bytes each, and the transmission destination 51 for setting the mobile station number of the transmission destination in 1 byte
To the other 1 byte, the transmission source 52 that sets the mobile station number of the own station, and to the other 17 bytes, the information / control unit 53 that sets what kind of control is to be performed to the remaining 17 bytes. A transmission data section 54 for setting data is assigned.

At this time, if "0" is set in the information / control unit 53, it means that normal communication is performed without control. When "1" is set, it indicates that the mobile station number request / response is controlled.
If "2" is set, the clock master ID
Indicates that notification control is performed. When "3" is set, it indicates that the clock master switching request / response is controlled. If "6" is set, CPU
It indicates that the notification of each parameter such as performance, free memory capacity, remaining battery capacity, electric field strength, reception error rate, propagation delay time, or number of retransmission requests is controlled.
When "7" is set, it indicates that the inspection data emission request / response, the interference detection notification, or the retransmission request is controlled. Note that the numbers set in these information / control units 53 are examples, and the numbers are not limited to these.

The communication data D1 and control data D2
To D6 and the detailed configuration of each transmission data section 54 of the control data D11 to D21, the communication data D1, and the control data D
2 to D6 and each control by the control data D11 to D21 will be described later.

(1) Determination of Clock Master An operation of determining a mobile station to be a clock master among a plurality of mobile stations (here, mobile stations 1 to 4) will be described.

Initially, none of the mobile stations 1 to 4 emits a radio wave for synchronization, and communication is not possible as it is. Therefore, it is necessary to determine the mobile station that emits the synchronization radio wave as the clock master.

Here, the synchronization radio wave means that the clock master is the CPU 29 in the control unit 18 and the TDMA / TDD processing unit 14, the modem unit 13, the RF unit 12, and the antenna 1.
Control data D4 of the clock master ID notification that is emitted at every time set in the synchronization radio wave emission interval A1 using any of the time-divided slots T1 to T4 shown in FIG. (See FIG. 7E).

The transmission data part of the control data D4 is P
It has a 28-bit area D4a for setting the S-ID. Further, "255" indicating broadcast is set to the transmission destination of the control data D4, and the mobile station number "1" indicating the clock master is set to the transmission source.

(1-1) Determination of Clock Master by Powering On Power Based on the flowchart of FIG.
A case will be described in which, from the state in which 4 (see FIG. 2) is OFF, the mobile station that is first powered on becomes the clock master. Here, it is assumed that the mobile station 1 is powered on first.

When the power of the mobile station 1 is turned on (S1), the mobile station 1 causes the synchronization signal detection section 24 in the control section 18 to
It is confirmed whether synchronization radio waves are emitted from the other mobile stations 2 to 4 (S2).

If the radio wave for synchronization is not detected in S2, it determines itself as the clock master, and the CPU 29 causes the TDMA / TDD processing unit 14, the modem unit 13, the RF unit 1 to operate.
2, and the antenna 11 is controlled to emit the synchronization radio wave using the time-divided slot T1 (S3).

On the other hand, when the synchronization radio wave is detected in S2, it is determined that the clock master already exists, the slave itself is determined to be the slave mode, and the clock master detected by the synchronization signal detector 24 is emitted. The operation of the CPU 29 is set so that the radio wave is emitted at the timing synchronized with the synchronization radio wave (S4).

(1-2) Determination of Clock Master by Retaining Transmission Data In addition to the example in which the mobile station turned on at the beginning of (1-1) becomes the clock master, it has data to be transmitted. Thus, a case where the mobile station that needs to start communication first becomes the clock master will be described with reference to the flowchart of FIG. Here, it is assumed that the mobile station 1 initially holds the data.

First, it is determined whether or not the mobile station 1 needs to start communication, that is, the CPU in the control unit 18 in the mobile station 1.
29 determines whether or not transmission data exists in the RAM 30 (S11). When the transmission data is held in S11, the mobile station 1 confirms by the synchronization signal detection unit 24 in the control unit 18 whether or not the synchronization radio wave is emitted from the other mobile stations 2 to 4. Yes (S12).

If the radio wave for synchronization is not detected in S12, it determines itself as the clock master, and the CPU 29 causes the TDMA / TDD processing unit 14, the modem unit 13, the RF unit 1 to operate.
2, and the antenna 11 is controlled to emit the synchronization radio wave using the time-divided slot T1 (S13).

On the other hand, when the transmission data is not held in S11, it is not necessary to become the clock master, so that the slave itself is determined as the slave mode, and when the synchronization radio wave is detected in S12, the clock is determined. It judges that the master already exists and determines itself as the slave mode. Then, the operation of the CPU 29 is set so that the radio wave is emitted at a timing synchronized with the radio wave emitted by the clock master, which is detected by the synchronization signal detection unit 24 (S14).

As described above, by determining the clock master by either of the above two methods,
In, for example, the mobile station 1 of the mobile stations 1 to 4 becomes the clock master mobile station CM, and the other three mobile stations 2 to 4
Are the mobile stations SL _{1 to} SL _{3 in the} slave mode, respectively. Then, by using the radio wave emitted from the mobile station CM as a radio wave for synchronization, it becomes possible for the mobile stations to perform wireless communication between mobile stations without passing through the base station.

(2) Radio Communication Between Mobile Stations Next, the operation of performing communication between mobile stations using the mobile stations CM and SL _{1 to} SL ₃ without going through the base station will be described. At this time, as shown in FIG. 9, the slot T1 is used for emitting the synchronization radio wave of the mobile station CM and the data transmission of the mobile station CM, and the slot R1 is used for the data reception of the mobile station CM. Slot R1 for data transmission of station SL
, And slot T1 is used for data reception of the mobile station SL. The mobile station SL is the mobile station SL ₁
And to indicate any mobile station of to SL _3.

First, the setting of the mobile station number will be described with reference to FIG.

When setting the mobile station number, FIG.
(C) The control data D2 and D3 shown in (d) are used.
The transmission data part of the control data D2 has an area D2a for setting the number "0" indicating the control of the mobile station number request and a 28-bit area D2b for setting the PS-ID of the own station. The transmission data part of the control data D3 includes an area D3a for setting the number "1" indicating the control of the mobile station number response and a 2-byte area D3 for setting the mobile station number.
b and a 28-bit area D3c for setting the PS-ID of its own station.

The mobile station CM that has become the clock master is
The mobile station number "1" which means the clock master corresponding to the S-ID is registered in the RAM 30 of the mobile station CM (S2).
1). After that, the mobile station CM emits the synchronization radio wave at each time set in the synchronization radio wave emission interval A1 as described above (S22).

When the mobile station SL receives the synchronization radio wave (S25), the PS of the mobile station CM included in the synchronization radio wave is received.
-ID is acquired (S26), and in the correspondence table shown in FIG. 6 in the RAM 30, "1" representing the clock master is registered as the mobile station number in association with the PS-ID (S2).
7).

Then, in order to obtain the mobile station number of the mobile station SL, the mobile station SL sets "1" representing the clock master to the destination of the control data D2 of the mobile station number request, and the control data D2 is set. Is transmitted to the mobile station CM (S28). At this time, since the mobile station SL has not yet acquired the mobile station number, "0" is set in the transmission source of the control data D2.

When the mobile station CM receives the control data D2 (S23), it refers to the correspondence table in the RAM 30 and outputs "2".
~ Set the smallest vacant number among the mobile station numbers of "4" in area D3b, and control data D for mobile station number response
3 is transmitted (S24). At this time, control the destination of the data D3 to set the mean broadcast "255" in order to receive the data to all mobile station SL ₁ to SL ₃ slave mode, the sender represent clock master "1 ”Is set.

All mobile stations SL _{1 to} SL _{3 in} slave mode
Since the transmission destination of the control data D3 is "255", after receiving the control data D3 (S29), the mobile station number is stored in association with the PS-ID in the correspondence table in each RAM 30. (S30).

[0069] As a result, the mobile station CM "1", for each mobile station to the mobile station SL ₁ to SL ₃ mobile station number "2" ~ "4" are assigned in correspondence with PS-ID, The mobile station numbers of all the mobile stations CM · SL _{1 to} SL ₃ are set.

Next, transmission / reception of data used between normal applications will be described.

In the case of normal data transmission / reception, FIG.
The communication data D1 shown in (b) is used. Communication data D
"1" corresponding to the mobile station you want to send to the destination of 1 ~
The mobile station number of "4", the mobile station number assigned to itself as the transmission source, and the data used for actual communication are set in the transmission data section.

The operation of the mobile station CM will be described first with reference to FIG.

The mobile station CM uses the slot R1 to check whether or not the mobile station SL is transmitting the communication data D1 (S31). As a result of the reception check in S31, if the communication data D1 from the mobile station SL is received, whether the data is data addressed to the mobile station CM (own station) based on the setting contents of the destination of the communication data D1. ,
It is determined whether the data is addressed to another mobile station SL (S32).

If the data is addressed to its own station in S32, the mobile station CM processes the data (S33). S in FIG.
An example in which data is transmitted from the mobile station SL ₂ to the mobile station CM is shown in L ₂ → CM. If the data is addressed to another mobile station SL in S32, the received data is transmitted as it is using the slot T1 (S34). SL in Figure 15
₂ → (CM) → SL ₃ An example in which data is transferred from the mobile station SL ₂ to the mobile station SL ₃ via the mobile station CM, SL ₂
→ (CM) → SL ₁ shows an example in which data is transferred from the mobile station SL ₂ to the mobile station SL ₁ via the mobile station CM.

Then, it is checked whether the mobile station CM itself holds transmission data (S35). If there is no transmission data in S35, a radio wave for synchronization is emitted (S3
6). On the other hand, when the transmission data is held in S35, the data is transmitted using the slot T1 (S3
7). For example, if "2" is set as the transmission destination and "1" is set as the transmission source, the data is transmitted from the mobile station CM to the mobile station SL ₁ (see CM → SL _{1 in} FIG. 15). As a result of the reception check of S31, if the data from the mobile station SL is not received, the process of S35 is performed without performing the processes of S32 to S34.

Next, the operation of the mobile station SL will be described with reference to FIG.

In the mobile station SL, the mobile station CM has a slot T1.
Is used to check whether the communication data D1 is not transmitted (S41). If the communication data D1 from the mobile station CM is received in S41, it is determined whether or not the data is addressed to the own station based on the setting contents of the transmission destination of the communication data D1 (S42). If the data is addressed to the own station in S42, the mobile station SL processes the data (S43).

After the processing of S43, if the data is not addressed to the own station in S42 or if the communication data D1 is not received in S41, the data is transmitted to the mobile station CM or another mobile station SL. It is checked whether or not the data is held (S44). If the transmission data is not held in S44, the process returns to the reception check process in S41. On the other hand, if the transmission data is held in S44, the data is transmitted in S45 and then the process returns to S41. For example, when the mobile station SL ₂ transmits data to the mobile station SL ₃ , the transmission destination of the communication data D1 is set to "4", the transmission source is set to "3", and the data is transmitted using the slot R1. To do.

(3) Switching of clock master during communication Switching of the mobile station CM during communication will be described. In this embodiment, the mobile station SL that first responds to the switching request from the mobile station CM becomes the next clock master.
That is, the mobile station CM is solicited for the next clock master, and the mobile station SL that first responds to it becomes the new clock master.

When switching the clock master, the control data D5 and D6 shown in FIGS. 7F and 7G are used. The transmission data part of the control data D5 has an area D5a for setting the number "0" indicating the control of the clock master switching request. Further, the transmission data part of the control data D6 has an area D6a for setting the number "1" indicating the control of the clock master switching response.

As shown in FIG. 17, when the mobile station CM wants to switch the operation as the clock master to another mobile station SL, that is, when the mobile station CM satisfies the condition of transmitting the clock master switching request (S51). Using the slot T1, "255" is set to the transmission destination of the control data D5 of the clock master switching request, and the control data D5 is transmitted (S52, see the first stage of FIG. 16).

The transmission destination in the control data D5 is "25".
5 ", all mobile stations SL _{1 to} SL ₃ in slave mode
Receives the control data D5 (S55). Control data D
5 of the mobile station SL ₁ to SL ₃ which has received a satisfying mobile station SL clock master switch response transmitted (S56)
Transmits the control data D6 of the clock master switching response to the mobile station CM using the next slot R1 (S57,
(See the second row in FIG. 16).

When the mobile station CM receives the control data D6 (S53), it switches to the slave mode mobile station (S54). On the other hand, the mobile station S that transmitted the control data D6
L becomes the new clock master (S58).

The new clock master uses the next slot T1 to set the transmission destination of the control data D4 of the clock master ID notification, which is the synchronization radio wave, to "255", and transmits the control data D4 (FIG. 16). See the third row). Also, the mobile station numbers of all the mobile stations CM / SL _{1 to} SL ₃ are changed.

The change of the mobile station number when the mobile station CM is switched to the slave mode mobile station and the mobile station SL becomes a new clock master will be described with reference to FIG. Here, the case where there are five mobile stations will be described as an example.

As shown in FIG. 18A, initially PS-I
When the mobile station whose D is "a" is operating as a clock master, the mobile station number of "a" is "1" and P
It is assumed that the mobile station numbers of the mobile stations in the slave mode whose S-IDs are "b" to "e" are "2" to "5", respectively.

Then, as shown in FIG. 18B, for example, when the mobile station "c" becomes the new clock master,
The mobile station number of "c" changed from "3" to "1", and the mobile station number of "a" that was switched from the clock master to the mobile station in slave mode is the largest mobile station in the slave mode. Change to the station number. That is, here it is "1"
→ It becomes “5”. The mobile station whose PS-ID is larger than the PS-ID before the new clock master of the mobile station that has become the new clock master has the PS-ID carried up, and the PS-ID of the small mobile station remains unchanged. Here, "d", "e"
Mobile station numbers are "3" and "4" respectively, and "b"
Mobile station remains "2".

(3-1) Conditions for transmitting clock master switching request The conditions for transmitting the clock master switching request by the mobile station CM in S51 of FIG. 17 are listed below. That is, FIG.
When any one of [Condition 1] to [Condition 8] shown in 4 is satisfied, the mobile station CM transmits the control data D5 of the clock master switching request.

[Condition 1] The mobile station CM which does not own the transmission data is controlled by the CPU 29 in the control unit 18 by RA
When it detects that there is no transmission data in M30,
The control data D5 is transmitted.

[Condition 2] The radio wave emitting mobile station CM for synchronization for a fixed time is controlled by the built-in timer 25 in the control unit 18.
The elapsed time from when the mobile station CM starts to operate as a clock master, that is, the elapsed time from when the mobile station CM starts to emit the synchronization radio wave is measured, and the elapsed time is set to the clock master switching interval A10. When it is detected that the value exceeds, the control data D5 is transmitted.

[Condition 3] The data relay mobile station CM for a fixed time is controlled by the built-in timer 25 in the control unit 18.
When the mobile station CM starts operating as a clock master, the accumulated time of relaying data between the mobile stations SL is measured, and when it is detected that the accumulated time exceeds the time set in the data relayable time A3, The control data D5 is transmitted.

[Condition 4] A certain amount of data relay The mobile station CM measures the amount of data relayed between the mobile stations SL by the CPU 29 in the control unit 18 after the mobile station CM starts operating as a clock master. When it is detected that the data amount exceeds the data amount set in the relayable data amount A11, the control data D5 is transmitted.

[Condition 5] The mobile station CM which has not transmitted data for a certain period of time is controlled by the built-in timer 25 in the control unit 18.
After the mobile station CM relays data between the mobile stations SL, the time until the next data is relayed is measured, and if the time exceeds the time set in the data non-transmission confirmation time A4, When it is detected that the data relay is not performed, the control data D5 is transmitted.

[Condition 6] Deterioration in Capability as Clock Master When the mobile station CM determines that its own capability as a clock master has deteriorated, it transmits control data D5 to the mobile station SL. Here, the ability as a clock master includes the high performance of the CPU 29 installed in the mobile station, the free memory capacity of the RAM 30, the remaining capacity of the built-in battery,
It is represented by the electric field strength of the received data from another station, the error occurrence rate of the received data, the propagation delay time of the received data, or the number of retransmission requests of the received data.

[Condition 6a] CPU Performance Degradation The mobile station CM measures the time during which the CPU 29 is idle within the time set in the CPU performance monitoring time A5 by the CPU monitoring unit 27 in the control unit 18, A CPU performance value represented by "CPU idle time / CPU performance monitoring time" is calculated.
This CPU performance value has become less than or equal to the value set in the CPU performance limit value C1, that is, CP
When it is detected that the U29 is idle for a short time due to other operations, and the CPU 29 has no room for its operation, the control data D5 is transmitted.

[Condition 6b] Free Memory Capacity Reduction The mobile station CM is controlled by the CPU 29 in the control unit 18 by RA
A free memory capacity value represented by "free memory capacity / total memory capacity" of M30 is calculated. When it is detected that the free memory capacity value becomes equal to or less than the value set in the free memory capacity limit value C2, that is, when the free space of the RAM 30 is exhausted, the control data D5 is transmitted.

[Condition 6c] Built-in Battery Capacity Reduction In the mobile station CM, the battery capacity monitoring section 26 in the control section 18 causes the "current voltage / voltage at full charge" of the built-in battery mounted in the mobile station CM. Calculate the battery remaining capacity value represented by. When it is detected that the remaining battery capacity value becomes equal to or less than the value set in the remaining battery capacity limit value C3, that is, when the remaining capacity of the built-in battery is exhausted, the control data D5 is transmitted.

[Condition 6d] Receiving Electric Field Strength Reduction The mobile station CM measures the electric field strength of the received data from the mobile station SL by the reception level detecting section 21 in the control section 18. This electric field strength value has become equal to or lower than the value set in the electric field strength limit value C4, that is, at least one mobile station S
When it is detected that the electric field strength between L and L becomes small and the relay of data is hindered, the control data D5 is transmitted.

[Condition 6e] Increasing reception error In the mobile station CM, the error detection unit 22 in the control unit 18 determines the number of error occurrences of the received data from the mobile station SL,
The measurement is performed during the time set in the reception error measurement interval A7, and the reception error rate value represented by "the number of data in which a reception error has occurred / the number of data received in the reception error measurement interval" is calculated. When the reception error rate value is equal to or more than the value set in the reception error rate limit value C5, that is, the error occurrence rate of the reception data increases with at least one mobile station SL, which hinders data relay. When it is detected that the error occurs, the control data D5 is transmitted.

[Condition 6f] Increase in propagation delay time When measuring the propagation delay time, the control data D17 and D18 shown in FIGS. 8 (g) and 8 (h) are used. The transmission data part of the control data D17 has an area D17a for setting the number "0" indicating the control of the inspection data emission request, and an area D17b for setting the value of the parameter for the inspection. Further, the transmission data part of the control data D18 has an area D18a for setting the number "1" indicating the control of the inspection data emission response and an area D18b for setting the value of the parameter for the inspection.

The mobile station CM sets "255" in the transmission destination and sets the value of the built-in timer 25 when transmitting data to the area D17b at each time set in the measurement data emission interval A9. All the mobile stations SL in the slave mode are transmitted by transmitting the control data D17 of the inspection data emission request.
_{1 to} SL ₃ are requested to transmit the control data D18 of the inspection data emission response. Each mobile station SL _{1 to} SL ₃
The built-in timer value when the control data D17 is received is set in the area D18b, and the control data D18 is transmitted to the mobile station CM.

The mobile station CM has the built-in timer value set in the control data D18 transmitted from the mobile station SL by the propagation delay time measuring section 23 in the control section 18 and the built-in timer of its own station (mobile station CM). Calculate the propagation delay value expressed as the difference from the value. This propagation delay time value is the propagation delay limit value C6.
Has exceeded the value set in, that is, at least 1
When it is detected that the data propagation delay time between one mobile station SL and the mobile station SL becomes large and the data relay is hindered, the control data D5 is transmitted.

[Condition 6g] Increase in number of retransmission requests When measuring the number of retransmission requests, the control data D20 shown in FIG. 8 (j) is used. The transmission data part of the control data D20 has an area D20a in which the number "3" indicating the control of the retransmission request is set.

When the mobile station CM detects that an error has occurred in the data received from the mobile station SL by the error detection section 22 in the control section 18, it transmits the retransmission request control data D20 to the mobile station SL. And request the data to be retransmitted. The number of times such a retransmission request is made is measured during the time set in the retransmission request measurement interval A12. This retransmission request count value has become equal to or larger than the value set in the retransmission request count limit value C7, that is, at least one mobile station SL.
Control data D5 is transmitted when it is detected that the number of times of data re-transmission between the two and the data becomes large and the data relay is hindered.

[Condition 7] Interference detection by clock master The mobile station CM measures the number of slots in which a slot error has occurred in the valid slots for 1.2 seconds by the error detection unit 22 in the control unit 18. This measured value is the mobile station CM
Channel switching FER (Frame Erro
r Rate) threshold or more, that is, second generation cordless telephone system standard second edition (RCRSTD-2
When the interference defined in 8) is detected, the control data D5
To send.

[Condition 8] Interference Detection by Mobile Station in Slave Mode The mobile station CM transmits the control data D5 when the mobile station SL is notified of the interference detection. When the mobile station SL notifies the mobile station CM of the interference detection, the control data D19 shown in FIG. 8 (i) is used. The transmission data part of the control data D19 has an area D19a in which the number "2" indicating the control of the interference detection notification is set.

That is, the mobile station SL measures the number of slots in which a slot error has occurred in the valid slots for 1.2 seconds by the error detection section 22 in the control section 18. This measurement value is preset in the mobile station SL.
When the interference becomes equal to or more than the ER threshold, that is, when the interference defined by the second generation cordless telephone system standard second edition (RCR STD-28) is detected, the control data D19 of the interference detection notification to the mobile station CM. To send. Mobile station CM
When the control data D19 is received, the control data D5
To send.

(3-2) Conditions for transmitting clock master switching response The conditions for transmitting the clock master switching response by the mobile station SL in S56 of FIG. 17 are listed below. That is, FIG.
When any one of [Condition 1] to [Condition 4] shown in 5 is satisfied, the mobile station SL transmits the control data D6 of the clock master switching response.

[Condition 1] The mobile station SL having the maximum capability as the clock master is the mobile stations SL _{1 to} SL in the slave mode.
_{When the} own station determines that the ability as the clock master is the maximum among the _three , the control data D6 is transmitted to the mobile station CM. Here, the ability as a clock master is (3-
This is as shown in [Condition 6] of 1).

[Condition 1a] The maximum CPU performance possessing mobile station SL measures the time during which the CPU 29 is idle within the time set in the CPU performance monitoring time A5 by the CPU monitoring unit 27 in the control unit 18. Then, the CPU performance value represented by "CPU idle time / CPU performance monitoring time" is calculated.
This CPU performance value is the previous value (currently RAM
(Value stored in 30), RAM3
CPU performance table B1 in 0 (see FIG. 5 (a))
In, the new CPU performance value is stored in the location corresponding to the mobile station number of the own station.

Further, the mobile station SL uses its own control data D11 shown in FIG. 8A to notify all other mobile stations of its own CP.
Notify U performance. The transmission data section of the control data D11 has an area D11a for setting the number "0" indicating the control of the CPU performance notification and an area D11b for setting the CPU performance value.

That is, the mobile station SL sets "255" to the destination of the control data D11, sets the calculated CPU performance value in the area D11b, and transmits the same to all the other mobile stations. To notify. on the other hand,
When the control data D11 is received from another station, the CPU performance value of the other station is stored in the CPU performance table B1 at a location corresponding to the mobile station number set as the transmission source of the control data D11. In this way, the CPU performances of all mobile stations are grasped.

The mobile station SL uses the CPU performance table B
When the CPU performance value of the own station stored in 1 is compared with the CPU performance value of the other station and the CPU performance of the own station is detected to be the highest, the control data D6 is transmitted.

[Condition 1b] The mobile station SL owning the maximum free memory capacity is controlled by the CPU 29 in the control unit 18 by RA
A free memory capacity value represented by "free memory capacity / total memory capacity" of M30 is calculated. When the free memory capacity value changes from the previous value, the new free memory capacity is stored in the free memory capacity table B2 (see FIG. 5B) in the RAM 30 at the location corresponding to the mobile station number of the own station. Stores the capacity value.

Further, the mobile station SL notifies all other mobile stations of the free memory capacity of its own station by using the control data D12 shown in FIG. 8 (b). The transmission data part of the control data D12 is a number "1" indicating the control of the free memory capacity notification.
And an area D12b for setting a free memory capacity value.

That is, the mobile station SL sets "255" to the transmission destination of the control data D12, sets the calculated free memory capacity value in the area D12b, and transmits it to all the other mobile stations. Notify the memory capacity. On the other hand, when the control data D12 is received from another station, the free memory capacity table B2
At, the free memory capacity value of the other station is stored in the location corresponding to the mobile station number set as the transmission source of the control data D12. In this way, the mutual free memory capacities of all mobile stations are grasped.

The mobile station SL compares the free memory capacity value of its own station and the free memory capacity value of another station stored in the free memory capacity table B2, and finds that the free memory capacity of its own station is the largest. When is detected, the control data D6 is transmitted.

[Condition 1c] The mobile station SL possessing the maximum internal battery capacity uses the battery capacity monitoring unit 26 in the control unit 18 to calculate "current voltage / full charge time" of the internal battery installed in the mobile station SL. Calculate the remaining battery capacity value of voltage. If this battery remaining capacity value changes from the previous value, RAM3
In the battery remaining capacity table B3 within 0 (see FIG. 5C),
The new battery residual capacity value is stored in the location corresponding to the mobile station number of the own station.

Further, the mobile station SL uses the control data D13 shown in FIG. 8 (c) to notify all the other mobile stations of the remaining battery level of the mobile station SL. The transmission data part of the control data D13 includes an area D13a for setting the number "2" indicating the control of the battery remaining capacity notification and an area D for setting the battery remaining capacity value.
13b.

That is, the mobile station SL sets "255" as the transmission destination of the control data D13, sets the calculated remaining battery capacity value in the area D13b, and transmits it to all the other mobile stations. Notify the remaining capacity. On the other hand, control data D from another station
When 13 is received, the remaining battery capacity value of the other station is stored in the battery remaining capacity table B3 at the location corresponding to the mobile station number set as the transmission source of the control data D13.
In this way, the remaining battery capacities of all mobile stations are grasped.

The mobile station SL compares the battery remaining capacity value of its own station and the battery remaining capacity value of the other station stored in the battery remaining capacity table B3, and finds that the battery remaining capacity of its own station is the largest. When is detected, the control data D6 is transmitted.

[Condition 2] The mobile station SL having the best transmission / reception state with other mobile stations is the mobile stations SL _{1 to} SL in the slave mode.
_When it is determined that the own station has the best transmission / reception state among the _three , the control data D6 is transmitted to the mobile station CM.

Here, the transmission / reception state with other stations is the sum of the deviations of the electric field strengths of the respective data transmitted from all mobile stations to the own station, the sum of the deviations of the reception error rates of the respective data, Total value of deviation of propagation delay time of each data, total value of deviation of retransmission request count of each data, total value of electric field strength of each data, total value of reception error rate of each data, each data It is represented by the total value of the propagation delay times or the total value of the number of retransmission requests of each data.

The sum of the deviations due to the above-mentioned various parameters means that the smaller the deviation sum is, the more equal the capacity is to each mobile station existing in the network. That is, a mobile station with a small total deviation value can perform good communication with any mobile station.

[Condition 2a] The total value of the deviation of the electric field strength is minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the electric field strength of the reception data of the own station with respect to the other station.

Here, each mobile station CM · SL _{1 to} SL ₃
Has a respective mobile stations CM · SL ₁ ~SL ₃ respectively field strength in RAM30 respectively corresponding to Tables B4 (see FIG. 5 (d)). Specifically, as shown in FIG.
Four electric field strength tables B4 _(CM) , B4 _(SL1) , B4 _(SL2) ,
Each has B4 _(SL3) .

The mobile station CM sets "255" in the transmission destination and transmits the control data D17 of the inspection data emission request at each time set in the measurement data emission interval A9,
It requests all the mobile stations SL _{1 to} SL _{3 in the} slave mode to transmit the control data D18 of the inspection data emission response. Each of the mobile stations SL _{1 to} SL ₃ sets the transmission destination to “255” in the order of the mobile station number and transmits the control data D18 of the inspection data emission response (see FIG. 19).

The mobile station SL _{1 which} has received the control data D18 from the mobile station SL ₂ is normally processed by the reception level detection unit 21 in the control unit 18 so that the slot R normally used by the mobile station CM is used.
1 is used to measure the electric field strength of the own station with respect to the mobile station SL ₂ . When this electric field strength value (for example, X) changes from the previous value, the electric field strength table B4 of the own station (mobile station SL ₁ ).
_(SL1) (see FIG. 20 (b)), the portion corresponding to that mobile station number "3" is set to the transmission source of the control data D18 from the mobile station SL _2, and stores the electric field intensity value X .

Further, the mobile station SL ₁ uses the control data D14 shown in FIG.
₂ · SL ₃ is notified of the electric field strength (electric field strength value X) of mobile station SL ₁ with respect to mobile station SL ₂ . Control data D above
The transmission data unit 14 includes an area D14a for setting the number "3" indicating the control of the electric field strength notification, an area D14b for setting the mobile station number, and an area D for setting the electric field strength value.
14c.

That is, the mobile station SL₁ Is the control data D14
"255" as the destination of the control and control data in the area D14b
Change the mobile station number "3" set as the sender of D18 to
The electric field strength value X is set in the area D14c and transmitted.
All mobile stations CM / SL₂ ・ SL ₃ And the above electric field strength value X
Notice. On the other hand, the mobile station SL₁ Control data from D14
Each mobile station CM / SL that received the₂ ・ SL₃ Is the control day
To the mobile station number “2” set as the sender of the data D14.
Corresponding electric field strength table B4_(SL1) (Figs. 20 (a) (c)
(See (d)), the number corresponding to the mobile station number “3”
The electric field strength value X is stored in the place.

Similarly to the above, the electric field strength value (for example, Y) of the mobile station SL ₁ with respect to the mobile station SL ₃ is the mobile station CM.
It is stored in · SL ₁ each electric field strength to SL ₃ Table B4 _(SL1). The electric field strength of the mobile station SL ₁ with respect to the mobile station CM is measured when the control data D17 of the inspection data emission request is received, and the electric field strength value (for example, Z) is also the electric field strength table B4 ₍ It is stored in _SL1) .

Further, each mobile station S other than the mobile station SL _{1 is}
The electric field strength is similarly measured for L ₂ and SL ₃ .
In this way, the electric field strength of the own station with respect to the other stations is grasped by all the mobile stations.

After that, the electric field strength table B4_(SL1) Electric field strength
Mobile station SL using the values X, Y, Z ₂ ・ SL₃ ・ To CM
Mobile station SL to₁ The variation (deviation) of the electric field strength of
Calculate each. Similarly, the electric field strength table B4_(SL2) Or
Mobile station SL₂ Of the electric field strength table B4_(SL3) To mobile station S
L₃ The respective variations in the electric field strength of are calculated.

The mobile station SL compares the total value of the deviation of the electric field strength of its own station with the total value of the deviation of the electric field strength of other stations, and finds that the total value of the deviation of the electric field strength of its own station is the smallest. When detected, the control data D6 is transmitted.

[Condition 2b] The total value of the deviation of the reception error rate is the minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the error occurrence rate of the reception data of the own station with respect to the other station.

As in the case of the above [condition 2a], the mobile station CM transmits the control data D17 of the inspection data emission request, and each of the mobile stations SL _{1 to} SL ₃ transmits the inspection data emission response control data D18. Send.

Control data D18 for sending inspection data emission response
The mobile station SL which has received the control data D by the error detection unit 22 in the control unit 18 uses the slot R1.
The presence or absence of 18 frame errors is inspected, and the reception error rate is calculated for each time set in the reception error measurement interval A7. If this reception error rate value changes from the previous value,
Reception error rate table B5 of its own station in the RAM 30 (FIG. 5 (e))
In the reference), the reception error rate value is stored at a location corresponding to the mobile station number set as the transmission source of the received control data D18.

Further, the mobile station SL uses the control data D15 shown in FIG. 8 (e) to notify all the other mobile stations of the reception error rate of its own station to the other stations. The transmission data section of the control data D15 includes an area D15a for setting the number "4" indicating the control of the reception error rate notification, an area D15b for setting the mobile station number, and an area D15c for setting the reception error rate value. Have

That is, the mobile station SL sets the destination of the control data D15 to "255" and the mobile station number set to the source of the control data D18 received in the area D15b.
A reception error rate value is set in the area D15c and transmitted, and all other mobile stations are notified of the reception error rate of their own station to other stations. On the other hand, the other mobile station SL that has received the control data D15 has a reception error rate table B5 corresponding to the mobile station number set as the transmission source of the control data D15. As in the case of B5, the reception error rate value is stored.

In this way, the reception error rate value is calculated for all the mobile stations SL _{1 to} SL _{3 in} the slave mode, and the reception error rate of its own station with respect to other stations is grasped between all the mobile stations.

After that, each mobile station SL _{1 to} SL ₃ receives each mobile station SL from the other stations based on the reception error rate table B5.
The variations (deviations) of the reception error rates of _{1 to} SL ₃ are calculated. The mobile station SL compares the total deviation of the reception error rates of its own station with the total deviation of the reception error rates of other stations, and determines that the total deviation of the reception error rates of its own station is the smallest. When detected, the control data D6 is transmitted.

[Condition 2c] The total value of the deviation of the propagation delay time is the minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the propagation delay time of the received data of the own station with respect to the other station.

As in the case of the above [condition 2a], the mobile station CM transmits the control data D17 of the inspection data emission request, and the mobile stations SL _{1 to} SL ₃ transmit the inspection data emission response control data D18. Send. Here, when the mobile station SL transmits the control data D18 of the test data emission response, the value of the built-in timer 25 of the own station when the control data D17 is received is set in the area D18b.

Control data D18 for sending inspection data emission response
The mobile station SL which has received the transmission delay time, which is the difference between the built-in timer value of the control data D18 and the built-in timer value of the local station, is measured by the propagation delay time measuring unit 23 in the control unit 18 using the slot R1. To calculate. When this propagation delay time value changes from the previous value, it is set as the transmission source of the received control data D18 in the propagation delay time table B6 (see FIG. 5 (f)) of the own station in the RAM 30. The propagation delay time value is stored in the location corresponding to the mobile station number.

Further, the mobile station SL uses the control data D16 shown in FIG. 8 (f) to notify all other mobile stations of the propagation delay time of the own station with respect to the other stations. The transmission data part of the control data D16 includes an area D16a for setting the number "5" indicating the control of the propagation delay time notification, an area D16b for setting the mobile station number, and an area D16c for setting the propagation delay time value. Have

That is, the mobile station SL sets "255" as the destination of the control data D16, the mobile station number set as the source of the received control data D18 in the area D16b, and the propagation delay time in the area D16c. Set value and send,
Notify all other mobile stations of their own propagation delay time with respect to other stations. On the other hand, the other mobile station SL that has received the control data D16 uses the propagation delay time table B6 corresponding to the mobile station number set as the transmission source of the control data D16.
Similar to the case of the propagation delay time table B6 of the mobile station SL,
The propagation delay time value is stored.

In this way, the propagation delay time is calculated for all the mobile stations SL _{1 to} SL _{3 in} the slave mode, and the propagation delay time of the own station with respect to other stations is grasped between all the mobile stations.

After that, each mobile station SL _{1 to} SL ₃ is based on the propagation delay time table B6, and each mobile station SL with respect to the other station.
The variations (deviations) of the propagation delay times of _{1 to} SL ₃ are calculated. The mobile station SL compares the total value of the deviations of the propagation delay times of its own station and the total value of the deviations of the propagation delay times of other stations, and confirms that the total value of the deviations of the propagation delay time of its own station is the smallest. When detected, the control data D6 is transmitted.

[Condition 2d] The total value of deviations in the number of retransmission requests is the minimum. The transmission / reception state with another station is evaluated by the total value of the deviations in the number of retransmission requests of received data of the local station to the other station.

As in the case of [Condition 2a] above, the mobile station CM transmits the control data D17 of the inspection data emission request, and the mobile stations SL _{1 to} SL ₃ transmit the inspection data emission response control data D18. Send.

Control data D18 for sending inspection data emission response
The mobile station SL which has received the control data D by the error detection unit 22 in the control unit 18 uses the slot R1.
Check for 18 frame errors. When a frame error is detected, the retransmission request control data D20 is transmitted, and the retransmission request count is calculated at each time set in the retransmission request count measurement interval A12. If this retransmission request count value changes from the previous value, it is set in the retransmission request count table B7 (see FIG. 5 (g)) of its own station in the RAM 30 as the source of the received control data D18. The number of times of retransmission request is stored in the location corresponding to the mobile station number.

Further, the mobile station SL uses the control data D21 shown in FIG. 8 (k) to notify all the other mobile stations of the number of times the own station has requested retransmission to the other stations. The transmission data part of the control data D21 includes an area D21a for setting the number "6" indicating the control of the notification of the number of retransmission requests, an area D21b for setting the mobile station number, and an area D21c for setting the value of the number of retransmission requests. Have

That is, the mobile station SL sets "255" as the transmission destination of the control data D21 and the mobile station number set as the transmission source of the control data D18 received in the area D21b.
A retransmission request count value is set in the area D21c and transmitted, and all other mobile stations are notified of the retransmission request count of their own station to other stations. On the other hand, the other mobile station SL that has received the control data D21, in the retransmission request count table B7 corresponding to the mobile station number set as the transmission source of the control data D21, uses the retransmission request count table B7 of the mobile station SL. The value of the number of times of retransmission request is stored as in the case of

In this way, the number of retransmission requests for all the mobile stations SL _{1 to} SL _{3 in} the slave mode is calculated, and the number of retransmission requests of its own station to other stations is mutually understood between all the mobile stations.

After that, each of the mobile stations SL _{1 to} SL ₃ sends each mobile station SL to another station based on the retransmission request count table B7.
The variations (deviations) of the number of retransmission requests of _{1 to} SL ₃ are calculated. The mobile station SL compares the total value of the deviations of the retransmission request times of its own station with the total value of the deviations of the retransmission request times of other stations, and determines that the total value of the deviations of the retransmission request times of its own station is the smallest. When detected, the control data D6 is transmitted.

[Condition 2e] The total value of the electric field strength is maximum. The transmission / reception state with the other station is evaluated by the total value of the electric field strength of the own station with respect to the other station.

Similar to the case of [Condition 2a], the electric field strengths of all the mobile stations SL _{1 to} SL _{3 in} the slave mode are calculated, and the electric field strengths of the own station with respect to other stations are grasped between all the mobile stations. .

[0158] Then, based on the electric field strength table B4 in each mobile station SL ₁ to SL _3, each mobile station SL ₁ ~ to other stations
The total value of the electric field strength of SL ₃ is calculated. The mobile station SL compares the total value of the electric field strengths of its own station with the total value of the electric field strengths of other stations, and when it detects that the total value of the electric field strengths of its own station is the largest, transmits the control data D6. To do.

[Condition 2f] The total value of the reception error rate is the minimum. The transmission / reception state with the other station is evaluated by the total value of the reception error rate of the reception data of the own station with respect to the other station.

Similar to the case of the above [condition 2b], the reception error rate is calculated for all the mobile stations SL _{1 to} SL _{3 in} the slave mode, and the reception error rate of the own station to the other stations is calculated between all the mobile stations. Figure out

Thereafter, each mobile station SL _{1 to} SL ₃ receives each mobile station SL _{1 from the} other stations based on the reception error rate B5.
The total value of the reception error rate to SL ₃ to be calculated.
When the mobile station SL detects that the total value of the reception error rates of its own station is the smallest by comparing the total value of the reception error rates of its own station with the total value of the reception error rates of other stations, Send D6.

[Condition 2g] The total value of the propagation delay times is the minimum. The transmission / reception state with other stations is evaluated by the total value of the propagation delay times of the reception data of the local station with respect to the other stations.

Similarly to the case of [Condition 2c], the propagation delay time is calculated for all the mobile stations SL _{1 to} SL _{3 in} the slave mode, and the propagation delay time of the own station with respect to other stations is calculated between all the mobile stations. Figure out

Thereafter, based on the propagation delay time table B6 in each mobile station SL _{1 to} SL ₃ , each mobile station SL with respect to another station
The total value of the propagation delay times of _{1 to} SL ₃ is calculated respectively. The mobile station SL compares the total value of the propagation delay times of its own station and the total value of the propagation delay times of other stations, and when it detects that the total value of the propagation delay times of its own station is the smallest, the control data Send D6.

[Condition 2h] The total value of the number of retransmission requests is the minimum. The transmission / reception state with the other station is evaluated by the total value of the number of retransmission requests of the reception data of the local station to the other station.

Similar to the case of [Condition 2d], the number of retransmission requests for all the mobile stations SL _{1 to} SL _{3 in} the slave mode is calculated, and the number of retransmission requests of the own station to other stations is calculated between all the mobile stations. Figure out

After that, each mobile station SL _{1 to} SL ₃ is based on the propagation delay time table B7, and each mobile station SL with respect to the other stations.
The total number of retransmission request times of _{1 to} SL ₃ is calculated. When the mobile station SL compares the total value of the number of retransmission requests of its own station with the total value of the number of retransmission requests of other stations, and detects that the total value of the number of retransmission requests of its own station is the smallest, the control data Send D6.

[Condition 3] The mobile station SL which has the smallest environmental change due to the switching of the clock master is the mobile stations SL _{1 to} SL in the slave mode.
_{When the} self station determines that the environment change due to the switching of the clock master is the smallest among the _three , the control data D6 is transmitted to the mobile station CM.

Here, the environmental change due to the switching of the clock master is represented by the electric field strength for the clock master, the reception error rate for the clock master, the propagation delay time for the clock master, and the number of retransmission requests for the clock master.

[Condition 3a] Maximum Electric Field Strength for Clock Master The environmental change due to switching of the mobile station CM is evaluated by the electric field strength of the mobile station SL for the mobile station CM.

As in the case of the above [condition 2a], the mobile station CM transmits the control data D17 of the inspection data emission request, and the mobile stations SL _{1 to} SL ₃ transmit the inspection data emission response control data D18. Send.

The mobile station CM measures the electric field strength of the control data D18 of the inspection data emission response from each of the mobile stations SL _{1 to} SL ₃ by the reception level detection unit 21 in the control unit 18. If these electric field strength values have changed from the previous values, "255" is set as the transmission destination of the control data D14 for the electric field strength notification, and the control data D received in the area D14b.
The mobile station number set as the transmission source of 18 is the area D
Send by setting the field intensity values measured 14c, notifies the field strength of the mobile station SL for the mobile station CM to all the mobile station SL ₁ to SL ₃ in slave mode. On the other hand, mobile station CM
Each of the mobile stations SL _{1 to} SL _{3 which} has received the control data D14 of the electric field strength notification from the device stores the electric field strength value in the electric field strength table B4 corresponding to the mobile station CM among the plural electric field strength tables B4. To do. In this way, the electric field strength of the mobile station SL with respect to the mobile station CM is grasped between all mobile stations.

When the mobile station SL compares the electric field strength of the mobile station CM of its own station with the electric field strength of the mobile station CM of another station, and detects that the electric field strength of its own station is the largest, the control data D6 is sent. To send.

[Condition 3b] The reception error rate with respect to the clock master is minimum. The environmental change due to the switching of the mobile station CM is evaluated by the reception error rate of the reception data of the mobile station SL with respect to the mobile station CM.

As in the case of [Condition 2a] above, the mobile station CM transmits the control data D17 of the inspection data emission request, and each of the mobile stations SL _{1 to} SL ₃ transmits the inspection data emission response control data D18. Send.

The mobile station CM uses the error detection unit 22 in the control unit 18 to inspect whether or not there is a frame error in the control data D18 of the inspection data emission response from each mobile station SL _{1 to} SL _{3 and} to measure the reception error. The reception error rate is calculated for each time set in the interval A7. When this reception error rate value changes from the previous value, the mobile station set to "255" as the transmission destination of the control data D15 of the reception error rate notification and the transmission source of the control data D18 received in the area D15b. A number is set in the area D15c with the calculated reception error rate value and transmitted, and all mobile stations SL in the slave mode are transmitted.
_{1 to} SL ₃ are notified of the reception error rate of the mobile station SL with respect to the mobile station CM. On the other hand, each of the mobile stations SL _{1 to} S that has received the control data D15 of the reception error rate notification from the mobile station CM
L ₃ is a mobile station CM in a plurality of reception error rate tables B5
The above reception error rate values are stored in the reception error rate table B4 corresponding to. In this way, the reception error rate of the mobile station SL with respect to the mobile station CM is grasped between all mobile stations.

When the mobile station SL compares the reception error rate of the mobile station CM of its own station with the reception error rate of the mobile station CM of another station, and detects that the reception error rate of its own station is the smallest, The control data D6 is transmitted.

[Condition 3c] Propagation delay time with respect to the clock master The environmental change due to the switching of the mobile station CM is evaluated by the propagation delay time of the reception data of the mobile station SL with respect to the mobile station CM.

As in the case of [Condition 2a] above, the mobile station CM transmits the control data D17 of the inspection data emission request, and the mobile stations SL _{1 to} SL ₃ transmit the inspection data emission response control data D18. Send. Here, when the mobile station SL transmits the control data D18 of the test data emission response, the value of the built-in timer 25 of the own station when the control data D17 is received is set in the area D18b.

When the mobile station CM has a propagation delay in the control unit 18,
By the inter-station measuring unit 23, each mobile station SL ₁ ~ SL₃ Inspection from
Built-in timer value of control data D18 for response to issuing inspection data
And the propagation delay time represented by the difference between the internal timer value of the local station
Calculate If this propagation delay value changes from the previous value
Is the destination of the control data D16 for propagation delay time notification.
Control data D that received "255" in area D16b
The mobile station number set as the transmission source of 18 is the area D1.
Set the calculated propagation delay time value in 6c and send it,
All mobile stations SL in slave mode₁ ~ SL₃ Mobile station CM
Is notified of the propagation delay time of the mobile station SL. on the other hand,
Control data D16 for notification of propagation delay time from mobile station CM
Each mobile station SL that received the₁ ~ SL₃ Is the slow propagation
Propagation delay time corresponding to the mobile station CM in the delay time table B6
The propagation delay time values are stored in Table B6. This
As described above, the movement to the mobile station CM is performed between all the mobile stations.
Understand the propagation delay time of the station SL.

When the mobile station SL compares the propagation delay time of the mobile station CM of its own station with the propagation delay time of the mobile station CM of another station, and detects that the propagation delay time of its own station is the smallest, The control data D6 is transmitted.

[Condition 3d] The Number of Retransmission Requests to the Clock Master is Minimum The environment change due to the switching of the mobile station CM is evaluated by the number of retransmission requests of the received data of the mobile station SL to the mobile station CM.

As in the case of [Condition 2a] above, the mobile station CM transmits the control data D17 of the inspection data emission request, and the mobile stations SL _{1 to} SL ₃ transmit the inspection data emission response control data D18. Send.

In the mobile station CM, the error detection unit 22 in the control unit 18 controls the control data D1 of the inspection data emission response.
The presence or absence of 8 frame errors is inspected. When a frame error is detected, the retransmission request control data D20 is transmitted, and the retransmission request count is calculated for each time set in the retransmission request count measurement interval A12. If this retransmission request count value has changed from the previous value, the transmission destination of the control data D21 of the retransmission request count notification is "255" and the transmission source of the control data D18 of the inspection data emission response received in the area D21b. the mobile station number is set, and transmits the set of calculated the number of retransmission requests value to the area D21c, the number of retransmission requests of the mobile station SL for the mobile station CM to all the mobile station SL ₁ to SL ₃ slave mode To notify. On the other hand, mobile station CM
Each of the mobile stations SL _{1 to} SL _{3 which} has received the control data D21 of the retransmission request notification from the retransmission request number table B7 corresponding to the mobile station CM among the plurality of retransmission request number tables B7 stores the above retransmission request number value. Store each. In this way, the number of retransmission requests of the mobile station SL to the mobile station CM is grasped between all mobile stations.

When the mobile station SL compares the number of retransmission requests of the mobile station CM of its own station with the number of retransmission requests of the mobile station CM of another station, and detects that the number of retransmission requests of its own station is the smallest, The control data D6 is transmitted.

[Condition 4] The response of the number-ordered mobile station SL assigned to the mobile station follows the mobile station number. That is, the mobile station SL transmits the control data D6 when detecting that the mobile station number of the mobile station SL is “2”.

As described above, the time division digital mobile radio communication system in this embodiment is provided with a plurality of mobile stations, and each of the mobile stations mentioned above has a free-running clock for establishing synchronization necessary for time division communication. In this configuration, there are two operation modes, that is, a master mode in which the frame timing is defined and operates, and a slave mode in which the frame mode is synchronized with a synchronization signal pattern transmitted from the mobile station in the master mode.

Here, one of the plurality of mobile stations is used as a clock master for operating in the master mode, and the remaining mobile stations are operated in the slave mode to perform radio communication between the plurality of mobile stations. In this case, while switching the clock master to the mobile station in the slave mode during communication, at the same time, one of all the mobile stations in the slave mode other than the clock master is switched to the master mode to be the next clock master. It has a feature.

According to this, each mobile station has two operation modes, a master mode and a slave mode. Therefore, if one of the plurality of mobile stations is used as a clock master, the mobile station does not pass through the base station. Wireless communication can be performed between mobile stations that do not exist.

Since the clock master can be switched during communication, the load is not concentrated only on the mobile station in the master mode. This makes it possible to distribute the load on all mobile stations.

In addition, for example, when communication is performed between a clock master and a mobile station in the slave mode, if one of the mobile stations moves and the communication state between the two mobile stations deteriorates, the conventional In the configuration, since the clock master cannot be switched during communication, communication may be interrupted. On the other hand, in the configuration of the present application, the clock master can be switched during communication, so that even in the above case, continuous communication is possible by using another mobile station as the clock master.

Further, the clock master which is first operated in the master mode is the mobile station which is activated first when the power is turned on among all the mobile stations. According to this, the mobile station which becomes the next operating state can perform communication smoothly, and it becomes possible to perform communication efficiently.

Further, the clock master initially operated in the master mode may be the mobile station that first needs to transmit data among all the mobile stations. According to this, a mobile station that does not transmit data even when it is in an operating state when the power is turned on does not become a clock master, and an excessive load due to becoming a clock master is not given to the mobile station.

The method of switching the clock master is as follows. The current clock master issues a switching request to all the mobile stations in the slave mode before the local station switches to the slave mode, and among the mobile stations in the slave mode receiving the request. Then, the mobile station in the slave mode that first responds to the current clock master becomes the next clock master.

The switch request from the current clock master is
(1) When the current clock master no longer holds the transmission data, (2) When a certain time has passed since the current clock master emitted the synchronization radio wave, (3) The current clock master is transmitted from the mobile station in slave mode. When the current clock master relays a certain amount of data from the mobile station in the slave mode, (5) it is detected that the current clock master has not relayed the data for a certain time. Time point, (6) Time point when it is determined that the ability of the current clock master as a clock master has deteriorated, (7)
This is performed when the current clock master detects the interference, or (8) when the mobile station in the current slave mode detects the interference of the current clock master.

In the case of the above (1), when there is no transmission data, the standby state is entered, and it is not necessary to be the clock master, so that the battery of such a mobile station is not consumed unnecessarily. In the case of (2), since the mobile stations in the network have the same period as the clock master, the battery consumption of each mobile station can be averaged. In the cases of (3) and (4), since the load of the data relay is distributed, the battery consumption of each mobile station can be averaged. In the case of (5), it is not necessary to continue the emission of the synchronization radio wave when there is no data to be relayed, and the emission of the synchronization radio wave can be stopped to prevent battery consumption. In the case of (6), since the clock masters that hinder the communication, such as the relay being disabled when the free memory capacity of the RAM is reduced, are switched, good communication can be maintained. In the cases of (7) and (8), since the clock master that interferes with communication due to interference is switched, it is possible to maintain good communication.

The response of the mobile station in the slave mode to the switching request from the current clock master is (1) the mobile station having the best clock master ability among all the mobile stations in the slave mode, and (2) the slave. Among all mobile stations in mode, the mobile station with the best transmission / reception status with other mobile stations,
(3) Among the mobile stations in slave mode, the mobile station with the smallest environmental change due to the switching of the clock master is performed, or (4) All mobile stations in slave mode are assigned serial numbers (mobile station numbers). By the number in order.

In the case of the above (1), the new clock master does not hinder the communication, so that the good communication can be maintained. In the case of (2), since the mobile station having the same capability as other stations in the network becomes the new clock master, the new clock master can perform good communication with any mobile station. it can. (3)
In this case, since the environment change due to the switching of the clock master can be suppressed as much as possible, it is possible to minimize the occurrence of an error due to the switching. In the case of (4), since the order of becoming the clock master is determined, the battery consumption of each mobile station can be averaged. Further, the response time in the slave mode can be shortened as compared with the cases of (1) to (3).

[Embodiment 2] The following will describe Embodiment 2 of the present invention in reference to FIG. 21 and FIG. For the sake of convenience of explanation, the same members as those shown in the drawings of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The time division digital mobile radio communication system of this embodiment has the same configuration as that of the first embodiment.
The determination of the clock master in (1) and the process of wireless communication between mobile stations in (2) are the same as in the first embodiment.
The switching process of the clock master during communication of (3) is different.

Therefore, only the switching process of the mobile station CM in communication will be described here. The present embodiment is characterized in that the mobile station CM appoints the mobile station SL which becomes the clock master next, and the mobile station SL which has received the appointment becomes the new clock master.

As shown in FIG. 21, when there is a mobile station SL that satisfies the conditions for the mobile station CM to make a nomination (S6
1) Using the slot T1, the mobile station number of the mobile station SL satisfying the above-mentioned designation condition is set to the destination of the control data D5 of the clock master switching request, and the control data D5 is transmitted (S62).

The mobile station SL which has received the control data D5
The control data D6 of the clock master switching response is transmitted to the mobile station CM using the next slot R1 (S65, S
66).

When the mobile station CM receives the control data D6 (S63), it switches to the slave mode mobile station (S64). On the other hand, the mobile station S that transmitted the control data D6
L becomes the new clock master (S67).

Like the first embodiment, the new clock master uses the next slot T1 to set the transmission destination of the control data D4 of the clock master ID notification, which is the synchronization radio wave, to "25".
5 is set to ", and transmits the control data D4. In addition, to change the mobile station number of all mobile stations CM · SL ₁ ~SL _3.

Next, the conditions for nominating the clock master in S61 of FIG. 21 will be described. That is, when any of [Condition 1] to [Condition 4] shown in FIG. 26 is satisfied, the mobile station C
M transmits the control data D5 of the clock master switching request.

[Condition 1] The mobile station CM having the maximum capability as a clock master is all the mobile stations SL _{1 to} SL in the slave mode.
_When the mobile station SL having the maximum capability as the clock master is detected in 3, the control data D5 is transmitted. Here, the capability as a clock master is as shown in (Condition 6) of (3-1) of the first embodiment.

[Condition 1a] Maximum CPU performance possession In the same manner as in [Condition 1a] of (3-2) of the first embodiment, the mobile station SL calculates the CPU performance value,
The CPU performance value is stored in the CPU performance table B1. That is, the mobile station SL uses C in the control unit 18.
The PU monitoring unit 27 measures the time during which the CPU 29 is idle within the time set in the CPU performance monitoring time A5, and calculates the CPU performance value represented by "CPU idle time / CPU performance monitoring time". . When this CPU performance value changes from the previous value (currently stored in the RAM 30), the new CPU is added to the location corresponding to the mobile station number of the own station in the CPU performance table B1 in the RAM 30. Stores performance value.

Then, the CPU performance notification control data D11 is used to notify the mobile station CM of the CPU performance of its own station. That is, the mobile station SL sets "1" representing the clock master to the destination of the control data D11 by setting the calculated CPU performance value in the area D11b and transmits the same to the mobile station CM. Notice.

On the other hand, the mobile station CM that has received the control data D11 has the CPU performance value of the mobile station SL at the location corresponding to the mobile station number set in the transmission source of the control data D11 in the CPU performance table B1. To store. In this way, the mobile station CM grasps the CPU performance of all the mobile stations SL _{1 to} SL _{3 in} the slave mode.

The mobile station CM uses the CPU performance table B.
1 based on 1, all mobile stations SL _{1 to} SL in slave mode
_{When the} mobile station SL having the highest CPU performance among the _three is detected, the control data D5 is transmitted to the mobile station SL.

[Condition 1b] Maximum free memory capacity possession In the same manner as in [Condition 1b] of (3-2) of the first embodiment, the mobile station SL calculates the free memory capacity value and displays the free memory capacity table. The free memory capacity value is stored in B2. Then, the free memory capacity notification control data D12 is used to notify the mobile station CM of the free memory capacity of its own station. Mobile station C
When M receives the control data D12, mobile station C
M grasps the free memory capacity of all mobile stations SL _{1 to} SL _{3 in} the slave mode. The mobile stations CM are mobile stations SL ₁ to.
Among the SL _3, when detecting a mobile station SL most free memory capacity is large, it sends the control data D5 to the mobile station SL.

[Condition 1c] Maximum internal battery capacity possession In the same manner as in the case of [Condition 1c] in (3-2) of the first embodiment, the mobile station SL calculates the remaining battery capacity value and displays the remaining battery capacity table. The remaining battery capacity value is stored in B3. Then, the mobile station CM is notified of the battery remaining capacity of its own station by using the control data D13 of the battery remaining capacity notification. The mobile station CM has control data D13
The mobile station CM recognizes the remaining battery capacities of all the mobile stations SL _{1 to} SL _{3 in} the slave mode by receiving the. Mobile station CM, when detecting a mobile station SL most remaining battery often in the mobile station SL ₁ to SL _3, and transmits the control data D5 to the mobile station SL.

[Condition 2] The mobile station CM having the best transmission / reception state with other mobile stations is the mobile stations SL _{1 to} SL in the slave mode.
_{When the} mobile station SL having the best transmission / reception state with other stations is detected among the _three stations, the control data D5 is transmitted to the mobile station SL. Here, the transmission / reception state with other stations is as shown in [Condition 2] of (3-2) of the first embodiment.

[Condition 2a] The total value of the deviation of the electric field strength is minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the electric field strength of the reception data of the own station with respect to the other station.

Similarly to the case of [Condition 2a] in (3-2) of the first embodiment, the mobile station SL measures the electric field strength value of its own station with respect to other stations, and records it in the electric field strength table B4 of its own station. Stores the electric field strength value. That is, the mobile station SL that has received the control data D18 of the inspection data emission response measures the electric field strength of the own station with respect to other stations by using the slot R1 by the reception level detection unit 21 in the control unit 18. If this electric field strength value changes from the previous value, the calculated electric field strength value at the location corresponding to the mobile station number set in the transmission source of the control data D18 in the electric field strength table B4 of the own station. To store.

Then, the control data D14 for notifying the electric field strength
Is used to notify the mobile station CM of the electric field strength of the own station to other stations. That is, the mobile station SL sets the destination of the control data D14 to "1", the area D14b to the mobile station number set as the source of the control data D18, and the area D14c to the calculated electric field strength value. Then transmit and mobile station C
Notify M of the electric field strength of the own station to other stations.

On the other hand, the mobile station CM which has received the control data D14 is the same as the electric field strength table B4 of the mobile station SL in the electric field strength table B4 corresponding to the mobile station number set as the transmission source of the control data D14. The electric field strength value is stored in the same manner as. In this way, the mobile station CM grasps the electric field strength for the other stations of the whole mobile station SL ₁ to SL ₃ in slave mode.

The mobile station CM, based on the electric field strength table B4 in the mobile station CM, sets the mobile stations SL _{1 to} SL ₃ for other stations.
Of each of the mobile stations SL _{1 to} SL ₃ in the slave mode having the smallest total value of the deviation of the electric field strength from the other stations, the control data is detected. Send D5.

[Condition 2b] The total value of the deviation of the reception error rate is the minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the error occurrence rate of the reception data of the own station with respect to the other station.

Similarly to the case of (condition 2b) in (3-2) of the first embodiment, the mobile station SL calculates the reception error rate value and stores the reception error rate value in the reception error rate value table B5. To do. Then, the mobile station CM is notified of the reception error rate of its own station with respect to other stations using the control data D15 of the reception error rate notification. When the mobile station CM receives the control data D15, the mobile station CM is transferred to all the mobile stations SL in the slave mode.
_{1 to} SL ₃ Understand the reception error rate for other stations. The mobile station CM calculates the variations (deviations) of the reception error rates of the mobile stations SL _{1 to} SL ₃ with respect to other stations based on the reception error rate value table B5 in the mobile station CM, and performs all movements in the slave mode. when the total value of the deviation of the reception error rate for the other stations in the station SL ₁ to SL ₃ detects the smallest mobile station SL, transmits the control data D5.

[Condition 2c] The total value of the deviation of the propagation delay time is the minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the propagation delay time of the received data of the own station with respect to the other station.

Similarly to the case of (condition 2c) in (3-2) of the first embodiment, the mobile station SL calculates the propagation delay time value and stores the propagation delay time value in the propagation delay time value table B6. To do. Then, the mobile station CM is notified of the propagation delay time of its own station with respect to other stations by using the control data D16 for notification of propagation delay time. When the mobile station CM receives the control data D16, the mobile station CM becomes the slave mode of all the mobile stations SL.
_{1 to} SL ₃ Understand the propagation delay time for other stations. The mobile station CM calculates the variations (deviations) of the propagation delay times of the mobile stations SL _{1 to} SL ₃ with respect to the other stations based on the propagation delay time value table B6 in the mobile station CM, and moves all the slave modes. When the mobile station SL having the smallest total deviation value of the propagation delay times with respect to the other stations among the stations SL _{1 to} SL ₃ is detected, the control data D5 is transmitted.

[Condition 2d] The total value of the deviation of the number of retransmission requests is the minimum. The transmission / reception state with the other station is evaluated by the total value of the deviation of the number of retransmission requests of the reception data of the local station to the other station.

Similar to the case of (condition 2d) in (3-2) of the first embodiment, the mobile station SL calculates the retransmission request count value and propagates it to the retransmission request count value table B7 (see FIG. 5). Stores the delay time value. Then, the mobile station CM is notified of the retransmission request count of its own station with respect to other stations using the control data D21 for notification of the retransmission request count shown in FIG. By mobile station CM receives control data D21, the mobile station CM grasps the number of retransmission requests for other stations of all the mobile stations SL ₁ to SL ₃ in slave mode. The mobile station CM calculates the variation (deviation) of the number of retransmission requests of each mobile station SL _{1 to} SL ₃ with respect to another station based on the retransmission request number value table B7 in the mobile station CM, and performs all movements in the slave mode. Station SL ₁ ~ SL
_{When the} mobile station SL having the smallest total deviation of the number of retransmission requests from other stations among the _three is detected, the control data D
5 is transmitted.

[Condition 2e] The total value of the electric field strength is maximum. The transmission / reception state with the other station is evaluated by the total value of the electric field strength of the own station with respect to the other station.

As in the case of [Condition 2a], all the mobile stations SL _{1 to} SL _{3 in} the slave mode respectively calculate the electric field strength and notify the calculation result to the mobile station CM, whereby the mobile station CM Is all mobile stations S in slave mode
Understand the electric field strength for other stations of L _{1 to} SL ₃ .

The mobile station CM uses the electric field strength table B of the mobile station CM.
4, the total value of the electric field strengths of the mobile stations SL _{1 to} SL ₃ for the other stations is calculated, and the total value of the electric field strengths of the other stations among all the mobile stations SL _{1 to} SL ₃ in the slave mode is calculated. When the largest mobile station SL is detected, the control data D5 is transmitted.

[Condition 2f] The total value of the reception error rate is the minimum. The transmission / reception state with the other station is evaluated by the total value of the reception error rate of the reception data of the own station with respect to the other station.

As in the case of [Condition 2b], all the mobile stations SL _{1 to} SL _{3 in} the slave mode respectively calculate the reception error rate and notify the calculation result to the mobile station CM. The CM grasps the reception error rate with respect to all the other mobile stations SL _{1 to} SL _{3 in} the slave mode.

Based on the reception error rate table B5 in the mobile station CM, the mobile station CM sends each of the mobile stations SL _{1 to} S to the other stations.
When the total value of the reception error rate of L ₃ is calculated and the mobile station SL having the smallest total reception error rate of the other stations among all the mobile stations SL _{1 to} SL ₃ in the slave mode is detected, the control data is calculated. Send D5.

[Condition 2g] The total value of the propagation delay times is the minimum. The transmission / reception state with other stations is evaluated by the total value of the propagation delay times of the reception data of the local station with respect to the other stations.

As in the case of [Condition 2c], all the mobile stations SL _{1 to} SL _{3 in} the slave mode respectively calculate the propagation delay time and notify the calculation result to the mobile station CM. The CM keeps track of the propagation delay time for all the mobile stations SL _{1 to} SL _{3 in} the slave mode with respect to the other stations.

Based on the propagation delay time table B6 in the mobile station CM, the mobile station CM sends each of the mobile stations SL _{1 to} S to the other stations.
When the total value of the propagation delay times of L ₃ is calculated and the mobile station SL having the smallest total value of the propagation delay times to other stations among all the mobile stations SL _{1 to} SL ₃ in the slave mode is detected, the control data is calculated. Send D5.

[Condition 2h] The total number of retransmission request times is the minimum. The transmission / reception state with another station is evaluated by the total number of retransmission request times of the reception data of the own station to another station.

As in the case of [Condition 2d], all the mobile stations SL _{1 to} SL _{3 in} the slave mode calculate the number of retransmission requests, and notify the calculation result to the mobile station CM. The CM keeps track of the number of retransmission requests to all other mobile stations SL _{1 to} SL ₃ in slave mode.

The mobile station CM, based on the retransmission request count table B7 in the mobile station CM, sets the mobile stations SL _{1 to} S for the other stations.
When the total value of the number of retransmission requests of L ₃ is calculated and the mobile station SL with the smallest total value of the number of retransmission requests to other stations is detected among all the mobile stations SL _{1 to} SL ₃ in the slave mode, control data is detected. Send D5.

[Condition 3] Minimal environmental change due to clock master switching The mobile station CM is the mobile station S with the smallest environmental change due to clock master switching among all mobile stations SL _{1 to} SL _3.
When L is detected, the control data D5 is transmitted to the mobile station SL. Here, the environmental change due to the switching of the clock master is as described in [Condition 3] of (3-2) of the first embodiment.

[Condition 3a] Maximum Electric Field Strength for Clock Master The environmental change caused by switching the mobile station CM is evaluated by the electric field strength of the mobile station SL for the mobile station CM.

In [Condition 3a] of (3-2) of the first embodiment
In the same manner as in the case, the mobile station CM determines each mobile station SL.₁ ~ S
L₃ Field strength for each mobile station CM
It If these field strength values change from the previous values,
Mobile station SL in mobile station CM ₁ ~ SL₃ Each corresponding to
The above electric field strength values are stored in the electric field strength table B4.
It In this way, the mobile station CM is in the slave mode.
All mobile stations SL₁ ~ SL₃ Grasp the electric field strength against.

When the mobile station CM detects the mobile station SL having the largest electric field strength with respect to the mobile station CM among all the mobile stations SL _{1 to} SL _{3 in} the slave mode based on the electric field strength table B4, the control data Send D5.

[Condition 3b] The minimum reception error rate with respect to the clock master The environmental change due to the switching of the mobile station CM is evaluated by the reception error rate of the reception data of the mobile station SL with respect to the mobile station CM.

[Condition 3b] in (3-2) of the first embodiment
In the same manner as in the case, the mobile station CM determines each mobile station SL.₁ ~ S
L₃ The reception error rate for the mobile station CM is calculated. This
If these reception error rate values change from the previous values, move
Mobile station SL in mobile CM ₁ ~ SL₃ Each receipt corresponding to
The received error rate table B5 shows the received error rate values.
Pay. In this way, the mobile station CM
All mobile stations SL₁ ~ SL₃ The reception error rate for
Hold on.

When the mobile station CM detects the mobile station SL having the smallest reception error rate with respect to the mobile station CM among all the mobile stations SL _{1 to} SL _{3 in} the slave mode based on the reception error rate table B5, The control data D5 is transmitted.

[Condition 3c] Propagation delay time with respect to the clock master The environmental change due to switching of the mobile station CM is evaluated by the propagation delay time of the reception data of the mobile station SL with respect to the mobile station CM.

[Condition 3c] in (3-2) of Embodiment 1
In the same manner as in the case, the mobile station CM determines each mobile station SL.₁ ~ S
L₃ The propagation delay time for the mobile station CM is calculated. This
If their propagation delay time value changes from the previous value, the
Mobile station SL in mobile CM ₁ ~ SL₃ Corresponding to
The propagation delay time values are listed in the seeding delay time table B6.
Pay. In this way, the mobile station CM
All mobile stations SL₁ ~ SL₃ The propagation delay time for
Hold on.

When the mobile station CM detects the mobile station SL having the smallest propagation delay time for the mobile station CM among all the mobile stations SL _{1 to} SL _{3 in} the slave mode based on the propagation delay time table B6, The control data D5 is transmitted.

[Condition 3d] The Number of Retransmission Requests to the Clock Master is Minimum The environmental change due to the switching of the mobile station CM is evaluated by the number of retransmission requests of the received data of the mobile station SL to the mobile station CM.

[Condition 3d] in (3-2) of Embodiment 1
In the same manner as in the case, the mobile station CM determines each mobile station SL.₁ ~ S
L₃ The number of retransmission requests for the mobile station CM is calculated. This
If the number of resend requests changes from the previous value,
Mobile station SL in mobile CM ₁ ~ SL₃ Each corresponding to
In the transmission request count table B7, the retransmission request count values are listed respectively.
Pay. In this way, the mobile station CM
All mobile stations SL₁ ~ SL₃ The number of resend requests for
Hold on.

When the mobile station CM detects the mobile station SL having the smallest number of retransmission requests to the mobile station CM among all the mobile stations SL _{1 to} SL _{3 in} the slave mode, based on the retransmission request number table B7, The control data D5 is transmitted.

[Condition 4] The numbering of clock masters assigned to the mobile stations in the order of numbers is based on the mobile station number. That is, the mobile station CM transmits the control data D5 when detecting the mobile station SL having the mobile station number “2”.

As described above, in the time division digital mobile radio communication system of this embodiment, as a method of switching the clock master, the clock master is in the slave mode which should become the next clock master before the own station switches to the slave mode. It is assumed that the mobile station is nominated and the slave mode mobile station that has received the designation becomes the next clock master.

The designation of the next clock master is (1)
A mobile station with the best ability as a clock master among all the mobile stations in the slave mode, (2) A mobile station with the best transmission / reception status with other mobile stations among all the mobile stations in the slave mode, or (3) Among all mobile stations in slave mode, the environment change caused by the clock master switching is the smallest, or (4) All mobile stations in slave mode are assigned serial numbers (mobile station numbers). By the number in order.

In the case of the above (1), the new clock master does not hinder the communication, so that the good communication can be maintained. In the case of (2), since the mobile station having the same capability as other stations in the network becomes the new clock master, the new clock master can perform good communication with any mobile station. it can. (3)
In this case, since the environment change due to the switching of the clock master can be suppressed as much as possible, it is possible to minimize the occurrence of an error due to the switching. In the case of (4), since the order of becoming the clock master is determined, the battery consumption of each mobile station can be averaged. Further, as compared with the cases of (1) to (3), the processing time for the clock master to designate the next clock master can be shortened.

[Third Embodiment] The third embodiment of the present invention will be described below with reference to FIGS. 22, 23, and 27. For the sake of convenience of explanation, the same members as those shown in the drawings of the above-described embodiment are designated by the same reference numerals, and the description thereof will be omitted.

The time division digital mobile radio communication system of this embodiment has the same configuration as that of the first embodiment.
The determination of the clock master in (1) and the process of wireless communication between mobile stations in (2) are the same as in the first embodiment.
The switching process of the clock master during communication of (3) is different.

Therefore, only the switching process of the mobile station CM in communication will be described here. The present embodiment is characterized in that the mobile station SL makes a switching request to the mobile station CM, and the mobile station SL making the request becomes the next clock master.

As shown in FIG. 22, when the mobile station SL satisfies the condition for transmitting the clock master switching request (S7).
1) Using the slot R1, "1" representing the clock master is set to the destination of the control data D5 of the clock master switching request, and the control data D5 is transmitted (S7).
2, see the first row in FIG. 23).

The mobile station CM which has received the control data D5
The control data D of the clock master switching response is sent to the mobile station SL which transmitted the control data D5 using the next slot T1.
6 is transmitted (S75, S76, see the second row of FIG. 23).

Upon receiving the control data D6 (S73), the mobile station SL becomes the new clock master (S7).
4). On the other hand, the mobile station CM that has transmitted the control data D6
The mobile station is switched to the slave mode (S77).

As in the case of the first embodiment, the new clock master uses the next slot T1 to set the transmission destination of the control data D4 of the clock master ID notification, which is the radio wave for synchronization, to "25".
5 is set to ", (see the third stage of FIG. 23) to the control data D4. In addition, to change the mobile station number of all mobile stations CM · SL ₁ ~SL _3.

Next, the conditions for transmitting the clock master switching request by the mobile station SL in S71 of FIG. 22 will be described. That is, when any of [Condition 1] to [Condition 4] shown in FIG. 27 is satisfied, the mobile station SL transmits the control data D5 of the clock master switching request. When there are a plurality of mobile stations SL that satisfy the clock master switching request transmission, it is assumed that the mobile station SL having the best capability, transmission / reception state, or environmental state among them makes the switching request.

[Condition 1] Good ability as a clock master When the mobile station SL determines that its own ability as a clock master is superior to the mobile station CM, the mobile station CM
To the control data D5. Here, the capability as a clock master is as shown in [Condition 6] of (3-1) of the first embodiment.

[Condition 1a] CPU Performance is Large Similar to the case of [Condition 1a] in (3-2) of the first embodiment, the mobile station CM calculates the CPU performance value. That is, the mobile station CM measures the time during which the CPU 29 is idle within the time set in the CPU performance monitoring time A5 by the CPU monitoring unit 27 in the control unit 18, and calculates "CPU idle time / CPU performance monitoring". Calculate the CPU performance value expressed in "time".

[0265] The CPU performance value is the previous value (currently, is to have a value stored in the RAM 30) If it is changed, the entire mobile station SL ₁ to SL ₃ slave mode using the control data D11 of the CPU performance notifications Notify the CPU performance of your station. That is, mobile station CM
Is a "255" to the destination of the control data D11, and transmits the set of calculated the CPU performance value to the area D11b, all the mobile station SL ₁ to SL slave mode
Notify the CPU performance of the mobile station CM to ₃ .

On the other hand, the mobile station SL which has received the control data D11 stores the CPU performance value of the mobile station CM in the CPU performance table B1 at a location corresponding to the mobile station number "1" representing the clock master. In this way, all mobile stations SL _{1 to} SL in the slave mode are
₃ grasps the CPU performance of the mobile station CM.

The mobile station SL calculates the CPU performance value of its own station as in the case of the mobile station CM, and detects that the CPU performance of its own station is higher than the CPU performance of the mobile station CM. At this time, the control data D5 is transmitted to the mobile station CM.

[Condition 1b] Free Memory Capacity is Large Similar to the case of [Condition 1b] in (3-2) of the first embodiment, the mobile station CM calculates the free memory capacity value. If this free memory value has changed from the previous value, and notifies the free memory capacity of the mobile station, to all the mobile station SL ₁ to SL ₃ slave mode using the control data D12 of free memory. All the mobile stations SL _{1 to} SL ₃ grasp the free memory capacity of the mobile station CM by receiving the control data D12.

The mobile station SL calculates the free memory capacity value of its own station as in the case of the mobile station CM, and the free memory capacity of its own station becomes larger than the free memory capacity of the mobile station CM. When it detects, the control data D5 is transmitted to the mobile station CM.

[Condition 1c] Large built-in battery capacity As in the case of [Condition 1c] in (3-2) of the first embodiment, the mobile station CM calculates the remaining battery charge value. When this remaining battery charge value changes from the previous value, all the mobile stations SL in the slave mode are used by using the remaining battery charge control data D13.
Notify _{1 to} SL ₃ of the remaining battery level of its own station. All mobile stations S
L ₁ to SL ₃ by receiving the control data D13, to grasp the residual battery capacity of the mobile station CM.

The mobile station SL calculates the battery remaining capacity value of its own station as in the case of the mobile station CM, and the battery remaining capacity of its own station becomes larger than the battery remaining capacity of the mobile station CM. When it detects, the control data D5 is transmitted to the mobile station CM.

[Condition 2] When the transmission / reception state with another mobile station is good, the mobile station SL detects that the transmission / reception state with respect to the other station of the own station is better than the transmission / reception state with respect to the other station of the mobile station CM. , And transmits control data D5 to the mobile station CM. Here, the transmission / reception state with other stations is as shown in [Condition 2] of (3-2) of the first embodiment.

[Condition 2a] The total value of the deviation of the electric field strength is small. The transmission / reception state with the other station is evaluated by the total value of the deviation of the electric field strength of the reception data of the own station with respect to the other station.

Similar to the case of (condition 2a) in (3-2) of the first embodiment, the mobile station CM measures the electric field strength value of its own station with respect to other stations. That is, the mobile station CM that has received the control data D18 of the inspection data emission response measures the electric field strength of its own station with respect to the other stations by the reception level detection unit 21 in the control unit 18. If this field strength value has changed from the previous value, and notifies the field strength of the mobile station CM to the other station to all the mobile station SL ₁ to SL ₃ slave mode using the control data D14 of the field intensity notification. That is, mobile station CM
Transmits “255” to the destination of the control data D14, the mobile station number set to the transmission source of the control data D18 to the area D14b, and the calculated electric field strength value to the area D14c, and transmits the field strength value. Notify all mobile stations SL _{1 to} SL ₃ of the electric field strength of the mobile station CM to other stations.

On the other hand, the mobile station SL which has received the control data D14 has the mobile station number set in the transmission source of the received control data D14 in the electric field strength table B4 of the mobile station number "1" representing the clock master. The measured electric field strength value is stored in the corresponding place. Also, the mobile station SL
Also, the electric field strength of the control data D18 transmitted by another mobile station SL is measured using the slot R1 normally used by the mobile station CM. When this electric field strength value changes from the previous value, the measured electric field strength value is stored in the electric field strength table B4 of the own station. In this way, all the mobile stations SL _{1 to} SL ₃ in the slave mode grasp the electric field strength of the mobile station CM with respect to the other stations and the electric field strength of the own station with respect to the other stations.

[0276] The mobile station SL, based on the electric field strength table B4 in the mobile station SL, each mobile station CM · SL ₁ ~ to other stations
The variation (deviation) of the electric field strength of SL ₃ is calculated, and it is detected that the total value of the electric field strength deviations of the local station with respect to the other stations is smaller than the total value of the electric field strength deviations of the mobile station CM with respect to the other stations. Control data D to the mobile station CM when
5 is transmitted.

[Condition 2b] The total deviation of the reception error rate is small. The transmission / reception state with the other station is evaluated by the total deviation of the error occurrence rate of the reception data of the own station with respect to the other station.

According to the same procedure as in the case of [Condition 2a] above.
, All mobile stations in slave mode SL ₁ ~ SL₃ Move
Reception error rate for other stations of the station CM and other stations
Understand the reception error rate for this.

Based on the reception error rate table B5 in the mobile station SL, the mobile station SL determines each mobile station CM / SL for other stations.
The dispersion (deviation) of the reception error rate of _{1 to} SL ₃ is calculated respectively, and the total value of the deviations of the reception error rate of the local station to the other stations is calculated from the total value of the deviations of the reception error rate of the mobile station CM to the other stations. Mobile station CM when it is detected that
To the control data D5.

[Condition 2c] Sum of deviations of propagation delay time is small. The transmission / reception state with other stations is evaluated by the sum of deviations of propagation delay time of reception data of the local station to other stations.

By the same procedure as in the case of [Condition 2a] above.
, All mobile stations in slave mode SL ₁ ~ SL₃ Move
Propagation delay time for other stations of station CM and other stations of own station
Understand the propagation delay time for the

The mobile station SL, based on the propagation delay time table B6 in the mobile station SL, sends each mobile station CM / SL to another station.
The dispersion (deviation) of the propagation delay times of _{1 to} SL ₃ is calculated respectively, and the total value of the deviations of the propagation delay times of the own station to other stations is calculated from the total value of the deviations of the propagation delay time of other stations of mobile station CM. Mobile station CM when it is detected that
To the control data D5.

[Condition 2d] The total value of deviations of the number of retransmission requests is small. The transmission / reception state with other stations is evaluated by the total value of the deviations of the number of retransmission requests of the reception data of the local station to the other station.

By the same procedure as in the case of [Condition 2a] above.
, All mobile stations in slave mode SL ₁ ~ SL₃ Move
Number of resend requests to other stations of station CM and other stations
Understand the number of resend requests for the

Based on the retransmission request count table B7 in the mobile station SL, the mobile station SL determines the mobile station CM / SL for each other mobile station.
Each of the variations (deviations) of the number of retransmission requests of _{1 to} SL ₃ is calculated, and the total value of the deviations of the number of retransmission requests to other stations of the own station is more than the total value of the deviations of the number of retransmission requests to other stations of the mobile station CM. Mobile station CM when it is detected that
To the control data D5.

[Condition 2e] The total value of the electric field strength is large. The transmission / reception state with the other station is evaluated by the total value of the electric field strength of the own station with respect to the other station.

As in the case of the above [condition 2a], all the mobile stations SL _{1 to} SL _{3 in} the slave mode are mobile stations CM.
Understand the field strength of other stations and that of other stations.

[0288] The mobile station SL, based on the electric field strength table B4 in the mobile station SL, each mobile station CM · SL ₁ ~ to other stations
When the total value of the electric field strengths of SL ₃ is calculated and it is detected that the total value of the electric field strengths of other stations of the own station is larger than the total value of the electric field strengths of other stations of the mobile station CM, the mobile station CM To the control data D5.

[Condition 2f] The total value of the reception error rate is small. The transmission / reception state with the other station is evaluated by the total value of the reception error rate of the reception data of the own station with respect to the other station.

As in the case of the above [condition 2b], all the mobile stations SL _{1 to} SL _{3 in} the slave mode are mobile stations CM.
Understand the reception error rate for other stations and the reception error rate for other stations of the own station.

Based on the reception error rate table B5 in the mobile station SL, the mobile station SL determines the mobile station CM / SL for each other mobile station.
Calculate the sum of the reception error rates of _{1 to} SL ₃ , respectively,
The total value of the reception error rates for other stations of the own station is the mobile station C
When it is detected that it is smaller than the total value of the reception error rates of M other stations, the control data D5 is transmitted to the mobile station CM.

[Condition 2g] Total propagation delay time is small. The transmission / reception state with the other station is evaluated by the total propagation delay time of the reception data of the local station with respect to the other station.

Similar to the case of [Condition 2c], all the mobile stations SL _{1 to} SL _{3 in} the slave mode are mobile stations CM.
Understand the propagation delay time for other stations and the propagation delay time for other stations of the own station.

Based on the propagation delay time table B6 in the mobile station SL, the mobile station SL determines each mobile station CM / SL for other stations.
Calculate the total value of propagation delay time of ₁ ~ SL ₃ , respectively,
The total value of the propagation delay times for other stations of the own station is the mobile station C
When it is detected that it is smaller than the total value of the propagation delay times for M other stations, the control data D5 is transmitted to the mobile station CM.

[Condition 2h] The total number of retransmission requests is small. The transmission / reception state with other stations is evaluated by the total number of retransmission requests of the received data of the own station to other stations.

As in the case of [Condition 2d], all the mobile stations SL _{1 to} SL _{3 in} the slave mode are mobile stations CM.
Understand the number of retransmission requests made to other stations and the number of retransmission requests made to other stations of the own station.

Based on the retransmission request count table B7 in the mobile station SL, the mobile station SL determines the mobile stations CM / SL for other stations.
Calculate the total number of retransmission requests for _{1 to} SL ₃ ,
The total value of the number of retransmission requests to other stations of the own station is the mobile station C
When it is detected that it is smaller than the total value of the number of retransmission requests to M other stations, the control data D5 is transmitted to the mobile station CM.

[Condition 3] The clock master switching request transmission of the number-ordered mobile station SL assigned to the mobile station follows the mobile station number. That is, the mobile station SL having the mobile station number “2” measures the elapsed time after the mobile station CM operates as the clock master by the built-in timer in the control unit 18,
When it is detected that the elapsed time exceeds the time set in the clock master switching interval A10, the control data D5 is transmitted.

[Condition 4] When an attempt is made to perform communication between two mobile stations SL which are in a good transmission / reception state by inter-mobile station communication in slave mode,
The mobile station SL receives the mobile station S obtained via the mobile station CM.
It was judged that the transmission / reception state obtained when the mobile station SL-communication partner mobile station SL directly communicates without passing through the mobile station CM is better than the transmission / reception state between the L-communication partner mobile station SL. At this time, the control data D5 is transmitted to the mobile station CM so that direct communication can be performed without going through the mobile station CM.

Here, the good transmission / reception state is the mobile station CM.
It is evaluated based on the difference in electric field strength depending on the presence or absence of relay, the difference in reception error rate, the difference in propagation delay time, and the difference in the number of retransmission requests.

[Condition 4a] The transmission / reception state in which the electric field strength is large in the inter-mobile station communication in the slave mode is evaluated by the difference in the electric field strength depending on the presence / absence of relay of the mobile station CM.

Similar to the case of [Condition 2a], the mobile station CM measures the electric field strength value of its own station with respect to other stations, and when this electric field strength value changes from the previous value, the electric field strength notification is sent. and notifies the field strength of the mobile station CM to the other station to all the mobile station SL ₁ to SL ₃ slave mode using the control data D14. Further, the mobile station SL that has received the control data D14 stores the measured electric field strength value in the electric field strength table B4 of the mobile station SL itself (mobile station SL).

At the same time, the mobile station SL controls the controller 18
The reception level detection unit 21 in the unit normally receives the slot R1 used by the mobile station CM,
The electric field strength of the control data D18 transmitted by is measured. When the electric field strength value changes from the previous value, the measured electric field strength value is stored in the electric field strength table B4 of the own station (mobile station SL). Thereby, the electric field strength between the mobile station SL and the mobile station SL with which the communication is performed can be obtained.

The mobile station SL uses the electric field strength table B4 to determine the electric field strength (s) between the mobile station CM and its own station and the mobile station CM.
-Comparing the average value ((s + t) / 2) with the electric field strength (t) between the communication partner mobile stations SL and the electric field strength (u) between the self station and the communication partner mobile station SL, the self station-communication Partner mobile station SL
When it is detected that the electric field strength between them is large, that is, the relationship of (s + t) / 2 <u is satisfied, the control data D5 is transmitted to the mobile station CM.

[Condition 4b] The transmission / reception state in which the reception error rate in the slave mode between mobile stations is small is evaluated by the difference in the reception error rate depending on the presence / absence of relay of the mobile station CM.

As in the case of [Condition 2b], the mobile station CM measures the reception error rate of its own station with respect to other stations,
When this reception error rate value changes from the previous value, all the mobile stations SL _{1 to} SL ₃ in the slave mode are sent to the mobile station CM for other stations by using the control data D15 of the reception error rate notification.
Notify the reception error rate of. The mobile station SL that has received the control data D15 stores the measured reception error rate value in the reception error rate table B5 of its own station (mobile station SL).

At the same time, the mobile station SL has the control unit 18
The error detection unit 22 in the unit normally receives the slot R1 used by the mobile station CM, measures the presence / absence of a frame error in the control data D18 transmitted by the communication partner mobile station SL, and sets the reception error measurement interval A7. The reception error rate is calculated for each time period. When this reception error rate value changes from the previous value, the calculated reception error rate value is stored in the reception error rate table B5 of the own station (mobile station SL).

From the reception error rate table B5, the mobile station SL
"1- {1- (reception error rate between mobile station CM and own station)}
The value obtained by the calculation of “× {1- (reception error rate between mobile station CM / communication partner mobile station SL)}” is compared with the reception error rate between the own station and the communication partner mobile station SL. Then, when it is detected that the reception error rate between the own station and the communication partner mobile station SL is high, the control data D5 is transmitted to the mobile station CM.

[Condition 4c] The transmission / reception state in which the propagation delay time due to the inter-mobile station communication in the slave mode is small is evaluated by the difference in the propagation delay time depending on the presence / absence of relay of the mobile station CM.

Similarly to the case of [Condition 2c], the mobile station CM measures the propagation delay time of its own station with respect to other stations,
If this propagation delay time value has changed from the previous value, the mobile station CM to the other station to all the mobile station SL ₁ to SL ₃ slave mode using the control data D16 of the propagation delay time notification
Notify the propagation delay time of. The mobile station SL that has received the control data D16 stores the measured propagation delay time value in the propagation delay time table B6 of its own station (mobile station SL).

At the same time, the mobile station SL has the control unit 18
Normally, the mobile station CM is
Receiving the slot R1 used by the mobile station S
The propagation delay time, which is the difference between the internal timer value of the control data D18 transmitted by L and the internal timer value of the local station, is calculated.
When this propagation delay time value changes from the previous value, the calculated propagation delay time value is stored in the propagation delay time table B6 of the own station (mobile station SL).

From the propagation delay time table B6, the mobile station SL
The total value of the propagation delay time between the mobile station CM and the own station and the propagation delay time between the mobile station CM and the communication partner mobile station SL, and the own station-
The propagation delay time between the communicating mobile stations SL is compared. Then, when it is detected that the propagation delay time between the own station and the communication partner mobile station SL is large, the control data D5 is sent to the mobile station CM.
To send.

[Condition 4d] The number of retransmission requests by inter-mobile station communication in the slave mode is small. The mobile station S is subjected to the same procedure as in [Condition 4c] above.
L is the number of retransmission requests between the mobile station CM and its own station and the mobile station CM
-A total value of the number of retransmission requests between the mobile stations SL of the communication partner, and
The number of retransmission requests between the mobile station SL and the local station is compared. Then, when it is detected that the number of retransmission requests between the own station and the mobile station SL of the communication partner is large, control data D5 is transmitted to the mobile station CM.

As described above, as a method of switching the clock master of the time division digital mobile radio communication system of this embodiment, the mobile station in the slave mode makes a switching request to the current clock master, and the slave making the request. The mobile station in mode is assumed to be the next clock master.

The switching request to the current clock master is (1) when a mobile station having a capability superior to that of the current clock master is detected among all mobile stations in the slave mode, or (2) all mobile stations in the slave mode. It is performed when a mobile station whose transmission / reception status with other mobile stations is superior to the current clock master is detected, or (3) Serial numbers (mobile station numbers) for all mobile stations in slave mode. Are added in order according to the number, or (4) between the two mobile stations obtained via the current clock master when two mobile stations in two slave modes try to communicate with each other. If the transmission / reception state obtained when directly communicating between two mobile stations is better than the transmission / reception state of .

In the case of the above (1), since the mobile station having the ability as the clock master which is superior to the current clock master becomes the new clock master, it is possible to always perform good communication. In the case of (2), since the mobile station having the same capability as other stations in the network becomes the new clock master, the new clock master can perform good communication with any mobile station. it can. In the case of (3), since the order of becoming the clock master is determined, the battery consumption of each mobile station can be averaged. Further, as compared with the cases of (1) and (2), the processing time for the mobile station in the slave mode to make a switching request can be shortened. In the case of (4), without going through the current clock master,
Since direct communication can be performed between mobile stations in the slave mode, good communication can be performed without causing an error due to relay. In addition, it is possible to prevent consumption of the battery of the current clock master, which does not require communication.

[0317]

As described above, there are three ways of thinking about how to switch the clock master.

That is, the first idea is that the current clock master makes a switching request to all the mobile stations in the slave mode before the local station switches to the slave mode, and among the mobile stations in the slave mode which have received the request. Then, the mobile station in the slave mode that first responds to the current clock master becomes the next clock master.

The second idea is that the clock master nominates the mobile station in slave mode which should become the next clock master before the own station switches to the slave mode, and the mobile station in slave mode which has received the nomination selects the next clock. It will be the master.

The third way of thinking is that the mobile station in slave mode makes a switching request to the current clock master, and the mobile station in slave mode making the request becomes the next clock master.

As a result, the clock master can be switched during communication, so that the load is not concentrated only on the mobile stations in the master mode, and the load on all the mobile stations can be distributed. It has the effect of being possible.

The conditions for transmitting a switching request from the clock master, the response conditions for the mobile station in slave mode to the switching request from the clock master, the nominating condition for the next clock master, or the conditions for transmitting a switching request to the clock master are By making various settings, it is possible to provide the best communication environment according to the communication status that changes in real time and the status of the mobile station.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a mobile station that constitutes a time division digital mobile radio communication system according to a first exemplary embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a communication state between the mobile stations.

FIG. 3 is a block diagram showing control values stored in a ROM in the mobile station.

FIG. 4 is a block diagram showing other control values stored in the ROM.

5A to 5G are RAMs in the mobile station.
It is an explanatory view showing a table stored in.

FIG. 6 is an explanatory diagram showing a correspondence table of PS-IDs and mobile station numbers stored in the RAM.

7A to 7G are explanatory diagrams showing the configuration of communication data or control data.

8A to 8K are explanatory diagrams showing the configuration of each of other control data.

FIG. 9 is an explanatory diagram showing time slots in the communication between mobile stations.

FIG. 10 is a flowchart showing a clock master determination operation when the power is turned on.

FIG. 11 is a flowchart showing a clock master determination operation based on possession of transmission data.

FIG. 12 is a flowchart showing a mobile station number setting operation.

FIG. 13 is a flowchart showing a data transmission / reception operation of a clock master.

FIG. 14 is a flowchart showing a data transmission / reception operation of a mobile station in slave mode.

FIG. 15 is an explanatory diagram showing a data transmission / reception operation of the mobile station communication.

FIG. 16 is an explanatory diagram showing time slots when a mobile station in slave mode responds to a switching request from a clock master.

FIG. 17 is a flowchart when a clock master switching operation is performed in response to a switching request from the clock master.

18A shows a correspondence table of PS-IDs and mobile station numbers before the clock master switching operation, and FIG. 18B shows a correspondence table in which the mobile station numbers are changed by the clock master switching operation. FIG.

FIG. 19 is an explanatory diagram showing time slots in the case of transmitting and receiving the control data of the inspection data emission request and the control data of the inspection data emission response.

20A is an explanatory diagram showing a table stored in a RAM of a clock master, and FIGS. 20B to 20D are explanatory diagrams showing tables stored in a RAM of each mobile station in a slave mode.

FIG. 21 is a flow chart when a clock master switching operation is performed by the clock master designating the next clock master in the time division digital mobile radio communication system according to the second exemplary embodiment of the present invention.

FIG. 22 is a flowchart in the case where a clock master switching operation is performed in response to a switching request from a mobile station in a slave mode in the time division digital mobile radio communication system according to the third embodiment of the present invention.

FIG. 23 is an explanatory diagram showing time slots when the clock master responds to the switching request from the mobile station in the slave mode.

FIG. 24 is an explanatory diagram showing conditions of a clock master switching request transmission by the clock master.

FIG. 25 is an explanatory diagram showing conditions of a clock master switching response transmission of a mobile station in a slave mode in response to a switching request from the clock master.

FIG. 26 is an explanatory diagram showing conditions for designating a clock master.

FIG. 27 is an explanatory diagram showing conditions for transmitting a clock master switching request by a mobile station in slave mode.

[Explanation of symbols]

18 control section (to slave switching request means, next master candidacy means, next master nominating means, to master switching request means) 21 reception level detection section 22 error detection section 23 propagation delay time measurement section 24 synchronization signal detection section 25 built-in timer 26 Battery capacity monitor 27 CPU monitor 28 ROM 29 CPU 30 RAM

Front page continuation (72) Inventor Kazuhiro Tsubaki 22-22 Nagaike-cho, Abeno-ku, Osaka-shi, Osaka Within Sharp Corporation (56) Reference JP-A-8-298687 (JP, A) JP-A-3-71746 (JP , A) JP 4-165729 (JP, A) JP 62-194757 (JP, A) JP 61-260352 (JP, A) JP 63-3494 (JP, B1) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04Q ^7/ 00-7/38 H04B ⁷ /24-7/26

Claims (23)

(57) [Claims] 1. A master mode which operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. In the case of communicating as a station, it has a slave-to-slave switching requesting means for requesting clock master switching to all other mobile stations before switching to slave mode when the local station is operating in master mode. , When the local station is operating in slave mode, the above switching request was received from the clock master. Come, the mobile station, characterized in that the next clock master when response thereto, the own station among all mobile stations in the slave mode receives the switching request in response to the first to the current clock master. 2. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, if the station detects that it no longer holds the transmission data while it is operating in master mode, it sends a clock master switching request to all other mobile stations. A mobile station having means for requesting switching to a slave. 3. A master mode that operates by defining frame timing with a free-running clock to establish synchronization required for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, if it detects that a certain period of time has elapsed since its own station emitted the synchronization radio wave when it was operating in master mode, it clocks all other mobile stations. A mobile station having a slave switching requesting means for making a master switching request. 4. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when operating as a clock master, it has the function of relaying the data transmitted from a mobile station in slave mode to another mobile station in slave mode. When operating, data from another mobile station operating in slave mode must be relayed for a certain period of time. Upon detecting the mobile station characterized by having a pair slave switching request means for performing a switching request of the clock master to other all mobile stations. 5. A master mode that operates by defining frame timing with a free-running clock to establish synchronization required for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when operating as a clock master, it has the function of relaying the data transmitted from a mobile station in slave mode to another mobile station in slave mode. When operating, it is possible to relay a certain amount of data between other mobile stations operating in slave mode. When exiting, the mobile station characterized by having a pair slave switching request means for performing a switching request of the clock master to other all mobile stations. 6. A master mode that operates by defining frame timing with a free-running clock to establish synchronization required for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when operating as a clock master, it has the function of relaying the data transmitted from a mobile station in slave mode to another mobile station in slave mode. If it is operating, relay data from another mobile station operating in slave mode for a certain period of time. Upon detecting the absence, the mobile station characterized by having a pair slave switching request means for performing a switching request of the clock master to other all mobile stations. 7. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, if the station determines that its ability as a clock master has deteriorated when it is operating in master mode, it requests all other mobile stations to switch the clock master. A mobile station having means for requesting switching to a slave. 8. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, if the local station detects interference when the local station is operating in the master mode, a slave-to-slave switching request means that requests clock master switching to all other mobile stations is provided. A mobile station having. 9. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, if its own station is operating in master mode and an interference detection notification is received from another mobile station operating in slave mode, the clock is sent to all other mobile stations. A mobile station having a slave switching requesting means for making a master switching request. 10. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when the local station is operating in slave mode and the clock master switching request for all mobile stations is received from the clock master, the local station selects the clock master among all the mobile stations in slave mode. When the current clock master is detected, the next clock Mobile station characterized in that it comprises the following master candidacy means for performing a response telling that become Kumasuta. 11. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when the local station is operating in slave mode and a clock master switch request for all mobile stations is received from the clock master, the local station among other mobile stations in slave mode When it detects that the transmission / reception status with the mobile station of the Mobile station characterized in that it comprises the following master candidacy means for performing a response telling that become Kumasuta. 12. A master mode that operates by defining frame timing with a free-running clock to establish synchronization required for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when the local station is operating in slave mode and a clock master switch request for all mobile stations is received from the clock master, the local station among all the mobile stations in slave mode When it detects that the environment change due to master switching is minimal, the current clock master is selected. And,
A mobile station characterized by having next master candidacy means for responding that it will become the next clock master. 13. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode and the other mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when the local station is operating in slave mode and a clock master switching request for all mobile stations is received from the clock master, according to the serial number order assigned to all mobile stations in slave mode, Send a response to the current clock master indicating that it will become the next clock master. Mobile station characterized in that it comprises a static candidacy means. 14. A master mode that operates by defining frame timing with a free-running clock to establish synchronization required for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode, and the remaining mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. in the case of performing communications as station, local station when operating in the master mode, having a next following master nominating unit for nominating a mobile station of the slave mode to become the clock master before switching to the slave mode
And the slave mode specified by the next master nominating means.
When a clock master switch response from another mobile station is received,
Switch to the reverb mode, the station is nominated by the clock master, and the next clock
When operating as a cluster, after sending the clock master switch response,
According to the time slot that the lock master was transmitting
Frame-synchronized communication is inherited by transmitting the cycle radio wave.
A mobile station characterized by being continued . 15. The next master nominating means performs nomination of a next clock master to a mobile station having the best clock master ability among all mobile stations in the slave mode. Item 15. The mobile station according to Item 14. 16. The next master nominating means performs nomination of the next clock master to a mobile station having the best transmission / reception status with other mobile stations among all mobile stations in slave mode. The mobile station according to claim 14. 17. The next master nominating means performs the nomination of the next clock master to a mobile station having the smallest environmental change due to the switching of the clock master among all the mobile stations in the slave mode. The mobile station according to claim 14. 18. The next master nominating means performs the nomination of the next clock master in the order of serial numbers given to all mobile stations in slave mode.
The mobile station according to 4. 19. A master mode that operates by defining frame timing with a free-running clock to establish synchronization necessary for time division communication, and frame synchronization with a synchronization signal pattern transmitted from a mobile station in the master mode. A mobile station having two operation modes, an operating slave mode, one mobile station being a clock master operating in a master mode, and the remaining mobile stations operating in a slave mode being a plurality of mobile stations in a digital wireless communication system. When communicating as a station, when the station is operating in master mode, the slave mode
By receiving the clock master switching request of the mobile station
If your station switches to slave mode,
Switch mode to switch to slave mode.
When the local station is operating in the slave mode, it has a master-to-master switching request unit that requests the current clock master to switch the clock master and becomes the next clock master.
In addition, the switching request from the master-to-master switching request means
Time slot that the receiving clock master was transmitting
The frame is synchronized by transmitting the periodic radio wave according to
A mobile station characterized by continuing communication . 20. The above-mentioned master-to-master switching request means makes a clock master switching request when it detects that the local station is a mobile station having a superior ability as a clock master than the current clock master. The mobile station according to claim 19. 21. The above-mentioned master-to-master switching request means makes a clock master switching request when it detects that the mobile station is superior to the current clock master in the transmission / reception state between itself and another mobile station. The mobile station according to claim 19, wherein the mobile station is a mobile station. 22. The mobile station according to claim 19, wherein said master-to-master switching requesting means issues a clock master switching request in the order of serial numbers given to all mobile stations in the slave mode. 23. A mobile station operating as a clock master has a function of relaying data transmitted from a mobile station in a slave mode to another mobile station in a slave mode, wherein the means for requesting master switching is provided. When the local station in slave mode and a mobile station of another slave try to communicate with each other, the two slave stations move more than the transmission / reception state between the two mobile stations obtained via the current clock master. 20. The mobile station according to claim 19, wherein when it is detected that the transmission / reception state obtained when directly communicating between the stations is better, a request for switching the clock master is made.