JPH0258937A - Moving communication system - Google Patents

Abstract

PURPOSE:To cause the operation management of each mobile station in a base station to be correct by correctly setting the time of the timer of each mobile station based on the time of the reference timer of the base station, respectively, and reducing a time difference in timers between respective mobile stations. CONSTITUTION:The times of timers 35 of respective mobile stations 21-2n are automatically corrected by sending reference time data at the time of polling to respective mobile stations 21-2n from a base station 10 side. Consequently, the generation of the time difference in timers 35 between respective mobile stations 21-2n can be prevented, and the reliability of the time data collected from the mobile stations 21-2n can be increased. Thus, to respective delivery vehicles as mobile stations, the correct operation management can be always executed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention (Field of Industrial Application) The present invention relates to a mobile communication system such as an MCA system.

(Prior art) Conventionally, MCA (Mult
i Channel Access) system has been put into practical use. The MCA system is composed of an MCA control station and a plurality of subscriber groups B, as shown in FIG. Each is composed of The MCA control station performs line control between the command station 1 and the mobile station 2 and between the mobile stations 2 (accepting calls, detecting empty channels and specifying them), and performs line control between the command station 1 and the mobile station 2 for each group. 2 and between the mobile stations 2 and each other. The command station 1 is a base station established by each subscriber at a business office, etc., and communicates with each mobile station 2 belonging to the same group via the MCA control station A.

Further, one control channel and a plurality of communication channels (for example, 15 channels) are allocated to one MCA system. The MCA control station A constantly monitors the usage status of these communication channels, and when a call is made from the command station 1 or mobile station 2, if there is an empty channel among the above communication channels, the MCA control station A always monitors the usage status of these communication channels. The channel is designated via the control channel to all mobile stations 2 in the group including the command station or mobile station 2 that made the call. Note that if there are no free channels, a call channel is reserved. In contrast, command station 1
When each mobile station 2 receives a communication channel designation from the MCA control station A, it moves to this communication channel, and thereafter occupies this communication channel for a maximum of a certain period of time (for example, 1 minute) to perform the required communication.

At this time, communication is performed using the simplex communication method using BreathTalk. Therefore, with such a system, communication can be carried out by effectively utilizing the limited number of communication channels.

Incidentally, in recent years, attempts have been made to use this type of system to manage, for example, the operation of a large number of delivery vehicles.

That is, each delivery vehicle is provided with a wireless device including a data transmission device and a clock. Then, the base station performs polling (r:6 or periodically) on each of the delivery vehicles, which are mobile stations, to transmit data such as announcement time from each vehicle to a predetermined point, and the base station collects the data. , the operation of each vehicle is managed based on these data.With such a system, each delivery ltt is managed at a distribution center etc.
By constantly and accurately grasping the progress of both deliveries, it is possible to perform appropriate operation management, for example, by sending another vehicle to a store where delivery is delayed.

However, in such conventional systems, each delivery vehicle is provided with a time setting means for a clock attached to its wireless device.
The operator sets the time according to his/her preference for each vehicle. For this reason, if there is a difference in accuracy between the clocks of each vehicle, or if there is a time difference between the clocks used to set the time, there is a problem that the clock time will differ between vehicles. there were. Furthermore, even if the clocks and reference clocks of each vehicle are accurate, the operator manually sets the time, so there is a risk of setting the time incorrectly.

(Problems to be Solved by the Invention) As described above, in the conventional system, differences in clock time tend to occur between each mobile station, and as a result, the time data collected from each mobile station becomes inaccurate. This invention has the problem of 1111 that it hinders the operational management of mobile stations, and the present invention takes this into consideration and prevents clock time differences between mobile stations, thereby ensuring that the mobile stations always receive reliable information. An object of the present invention is to provide a mobile communication system that can transmit high-quality time data and accurately manage the operation of mobile stations.

[Structure of the Invention] (Means for Solving the Problems) The present invention is composed of a base station and a plurality of mobile stations connected to the base station via a wireless line, and each mobile station has a clock. In a mobile communication system in which the time data is transmitted to the base station along with other predetermined management data, and the base station manages the operation of each mobile station based on this data, the base station is provided with a reference time. and means for transmitting reference time data from the reference clock to each mobile station, and each of the mobile stations is provided with a time setting means, and the base station transmits the reference time data from the base station. Sometimes, this J! The time of the own station's clock is set according to quasi-time data.

(Operation) As a result, the time of each mobile station's clock is automatically set according to the time data sent from the base station. Therefore, the clock time of each mobile station is accurately set based on the base station's reference clock time, which reduces the clock time difference between each mobile station. . Therefore, the reliability of the time data sent from the mobile station to the base station is increased, which allows the base station to always properly manage the operation of each mobile station.

(Embodiment) FIG. 1 shows the configuration of main parts of a base station and a mobile station of a mobile communication system in an embodiment of the present invention.

First, the base station 10 includes a radio section 11 that is equipped with an antenna 11a and that transmits and receives data to and from a radio line, and a data exchanger: J.
! ! 1 part (MOD) 12 and data demodulating part (DMOD)
13, a control unit 14, and a basic monk clock (BTIM) 15. Among these, the reference clock 15 is a highly accurate clock using a crystal oscillator. Further, the control section 14 has, for example, a microcomputer as a main control circuit, and includes reference time sending control means 14a in addition to various control means related to data transmission. This base time sending control means 14a adds base time data of the reference clock 15 when sending polling data to each mobile station, which will be described later.

On the other hand, the mobile stations 21 to 2n include a radio section 31 equipped with an antenna 31a, a data modulation section (MOD) 32, a data demodulation section (DMOD) 33, a control section 34, and a clock whose time data can be externally set. (TIM) 35. Of these, the control section 34 has a microcomputer as a main control circuit, similar to the control section 14 of the base station 10, and includes a time setting control means 34a in addition to data transmission/reception control means. When polling data for the own station arrives from the base station 10, the time setting control means 34a compares the reference time data added to this polling data with the current time data of the clock 35 of the own station, and If the times do not match, the time on the clock 35 of the local station is reset to the reference time.

Next, the operation of the system configured as described above will be explained according to the control procedure of the control section. This system adopts a method in which data from the mobile stations 21 to 2n is sequentially collected by polling from the base station 10, and each mobile station 21 to 2n sends a polling request to the base station 10 when it wants to send data. do.

During standby, the control unit 14 of the base station 10 controls, for example, the second
As shown in the figure, in step 2a, the arrival of a polling request PR is monitored, and if a polling request PR arrives from an arbitrary mobile station in this state, the process moves to step 2b, where the mobile station that performs polling (for example, 21 ). Then, in step 2C, the reference time BT is read from the reference clock 15, and in step 2d, as shown in FIG. Send it like this. Incidentally, at this time, the identification information of the mobile station 21 to be polled is inserted into the polling data P.

On the other hand, during standby, the control section 34 of the mobile stations 21 to 2n repeatedly monitors the input of a data transmission instruction and monitors the arrival of polling data in steps 3a and 3c, as shown in FIG. When the operator inputs an instruction to send data, the process moves to step 3b, where the polling request PR described above is sent to the base station 10.

When the polling data P arrives from the base station 10 to the own station, the process moves from step 3C to step 3d, where management data DT that has already been separately stored, such as arrival time or departure time data at a predetermined store, is entered. Base station 1
Send it towards 0.

After confirming the completion of transmission of the management data DT in step 3e, the control unit 34 of the mobile station then proceeds to step 3f, where it reads the current time T from the clock 35 of its own station. In step 3g, this time T of the own station is compared with the reference time BT previously sent from the base station 10 together with the polling data P. If the difference between the two times is greater than a certain time and it is therefore determined that they do not match, the control unit 34 moves to step 3h and sets the time on the own station's clock 35 to the above-mentioned 2! The time is corrected to the quasi-time BT and returns to the standby state.

By the way, if the difference between the two times is within a predetermined time by comparing the times, it is determined that the clock 35 of the local station matches the reference time, and the station returns to the standby state.

On the other hand, the control unit 14 of the base station 10 provides the mobile station 21 with the polling data and reference time data (P+B
When the transmission of data T) is completed, the process moves to step 2e, where the arrival of management data DT from the mobile station 21 is monitored. Then, when the management data DT arrives, this data is stored in a management data storage section (not shown) and is displayed on a display panel or printed out to notify the person in charge of monitoring. Then, in step 2g, the control unit 14 determines whether or not polling of all mobile stations 21 to 2n has been completed.Since polling has not yet been completed, the control unit 14 returns to step 2b and polls the next mobile station 22. choose,
Steps 20 to 2f control the transmission of polling data and the reception of management data DT.

Thereafter, in the same manner, until polling for all mobile stations 21 to 2n is completed, the remaining mobile stations 2
Select steps 3 to 2n sequentially and perform steps 2C to 2 above.
The polling data transmission control and management data DT reception control by f are repeated.

On the other hand, each mobile station 23 to 2n receives the polling data P for itself from the base station 10, based on the time data BT added to the polling data P and sent as described above. It is determined whether the time on the own station's clock 35 is correct or not, and if it is not correct, it is corrected to the base time BT. In this way, the clock 35 of each mobile station 21 to 2n confirms and corrects the time each time polling occurs from the base station 10.

As described above, in this embodiment, the time on the clock 35 of each mobile station 21 to 2n can be automatically corrected by sending the reference time data BT from the base station 10 side. It is possible to prevent a time difference from occurring in the clock 35 between 20 and 20 minutes. Therefore, mobile stations 21-2
By increasing the reliability of the time data collected from n, it is possible to always perform accurate operation management for each delivery vehicle serving as a mobile station. In addition, in this embodiment, when polling each mobile station 21 to 2n, the reference time data B
T is sent out to adjust the time of the clock 35. That is, the time is adjusted before polling.

Therefore, compared to, for example, the case where the base station 10 sends the reference time data BT to each of the mobile stations 21 to 2n just for time adjustment, the radio link can be used more effectively.

Note that the present invention is not limited to the above embodiments. For example, in the above embodiment, each mobile station is configured to synchronize the time using a polling method, or the basic time data BT is transmitted to all mobile stations at the same time, thereby synchronizing the time at the same time. Good too. In addition, in the above embodiment, the base time and the local time are compared and the time is adjusted only when the two times differ by more than a certain time difference, or the time is adjusted each time the visit time data arrives. You may do so. Furthermore, although the above embodiment has been described for the case where it is applied to the MCA system, the mobile station
The present invention may also be applied to other mobile communication systems of the type in which time data is collected at a base station. In addition, the configurations and procedures of the reference time data sending means by the base station and the time setting means in the mobile station can be modified in various ways without departing from the gist of the present invention.

[Effects of the Invention] As described in detail above, according to the present invention, a base station is equipped with a reference clock for measuring the base time and means for transmitting reference time data from the base clock to each mobile station. , and each mobile station is provided with a time setting means, so that when the visit time data is sent from the base station, the time setting means sets the time of the own station's clock according to this basic time data. By doing so, it is possible to prevent clock time differences between mobile stations, and as a result, highly reliable time data can always be transmitted from mobile stations, and mobile station operation management can be performed accurately. Communication systems can be provided.

[Brief explanation of the drawing]

1 to 5 are for explaining a mobile communication system according to an embodiment of the present invention. FIG. 1 is a circuit block diagram showing the main structure of the system, and FIGS. 2 and 3 are A flowchart showing control procedures and control contents of a base station control unit and a mobile station control unit of the same system, respectively;
FIG. 4 is a timing diagram showing how data is transmitted by the polling method, FIG. 5 is a diagram showing an example of the structure of data sent from a base station, and FIG. 6 is a schematic block diagram of the MCA system. 10...Base station, 11.31...Radio section, 12°32
...Data modulation section, 13.33...Data demodulation section,
14.34...Control unit, 14a...Basic time transmission control means, 34a...Time setting control means, 15...Clock, 35...Basic clock, 21-2n...Mobile station .

Claims (1)

[Claims] Consisting of a base station and a plurality of mobile stations connected to the base station via wireless lines, each mobile station is equipped with a clock and the time data is sent to the base station along with other prescribed management data. In a mobile communication system in which a base station manages the operation of each mobile station based on these data, the base station has a reference clock that measures a reference time, and a reference time data from this reference clock that is transmitted to each mobile station. each mobile station has time setting means for setting the time of its own clock according to the reference time data when the reference time data is sent from the base station. Characteristic mobile communication system.