JPH0319533A - Mobile communication system - Google Patents

Abstract

PURPOSE:To avoid the concentration of load to a control station by always monitoring a base station signal and judging the presence of a change in a base station zone when the mobile station is in the waiting state of re- registration timing. CONSTITUTION:When a receiver fault takes place in a base station 13, a data from a mobile station 107 just after the entry into a communication zone of a base station 13 does not reach a control station 1 and a data from mobile stations 102-104 in existence in the communication zone of the base station 13 does not reach the control station 1. Consequently, the control station 1 aborts the registration of the mobile station, while the mobile stations 102-104, 107 fail to apply re-registration processing and transit to the re-registration timing waiting state. Each mobile station detects a change in a base station identification number in a received data from the base station in the case of entering an adjacent base station 12 or 14 to start re-registration processing. Thus, the re-registration timing of each mobile station is distributed on time basis and the re-registration load to the control station is not concentration.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to mobile communication in which a mobile station, which starts receiving service after completing registration with a control station, communicates while moving between a plurality of communication zones. This is related to the method. [Prior Art] FIG. 5 is a flowchart showing the registration processing procedure of a conventional mobile communication system. (ST1) is an initial setting processing step, (ST2) is a registration request sending step, (ST3) is a registration response waiting step, (ST4) is a registration response receiving step, and (ST5) is a registration completion step.
(ST6) is a response timeout detection step. (ST7
) beam try step, (ST8) is re-registration wait timer start step, (ST9) is re-registration timing wait step, (STIO) is time-out step, (S
TII) is a process step for starting re-registration by discarding registration in the event of a control station communication failure. Next, the registration processing procedure will be explained according to this flowchart. First, the mobile station performs initial settings for registration (step STI). After completing the initial settings of the mobile station, first. The mobile station transmits a registration request to the base station (step ST2), and shifts to a registration response waiting state (step ST3). Here, if a registration response is received from the base station (step ST4),
Although the u-registration is completed (step ST5), if the registration response cannot be received within the specified time (step ST6).
Send the registration request again and move to the registration response waiting state.
The same procedure is repeated a predetermined number of times (step ST7), and if the 2M response cannot be received despite this, the mobile station starts a re-registration wait timer (step ST8) and then waits for re-registration timing. state (step ST9). Here, when the re-registration wait timer times out (step STIO). The registration process will begin again immediately (or after a random time delay depending on the system). Also, even after the registration has been completed, for some reason g! ．． If the record is discarded, the registration process is started again (step STII). [Problems to be Solved by the Invention] Conventional mobile communication systems carry out the registration process as described above, so that failures in control stations, individual base stations, or individual line failures between control stations and base stations can occur. If all or part of the mobile station information registered with the control station is discarded and many mobile stations need to re-register, all or a portion of the mobile station information registered with the control station may be accessed by the control station at almost the same time. In addition to placing a heavy load on the control station, the non-registration time of a mobile station is uniquely determined by the re-registration wait timer value, which poses problems such as not achieving the truly minimum unregistered time length. This invention was made in order to solve the above-mentioned problems, and even when it is necessary to re-register a large number of mobile stations, it does not place a large burden on the control station and allows individual base stations to be re-registered. The purpose of this paper is to obtain a mobile communication system that can minimize the length of time between unregistered mobile stations (s)# in the case of a station zone failure. [Means for Solving the Problems] The mobile communication system according to the present invention constantly monitors base station signals and determines whether there is a change in the base station zone when the mobile station is in a state of waiting for re-registration timing. This is how it was done. [Operation] The mobile communication system of the present invention constantly monitors the base station {i} when the registration of the mobile station with the control station is canceled or when the registration fails and the mobile station enters the re-registration timing wait state. The presence or absence of a change in the base station zone is determined in the step of detecting the base station identification number and ground controller, and the reregistration process is started when the change occurs or when the reregistration wait timer times out. [Embodiment of the Invention] An embodiment of the invention will be described below with reference to the drawings. 1st
In the figure, 1 is a control station that constitutes a mobile communication system;
Reference numerals 11 to 16 refer to base stations having communication zones along railway tracks, 21 to 26 refer to lines connecting the base stations 11 to 16 and the control station 1, respectively, and 101 to 107 refer to communication zones between the base stations 1l to 16. A mobile station (train) that communicates while moving.
It is. Next, we will explain the operation. Base stations 11-16
A mobile station, for example, mobile station 107, enters the control zone from outside the communication zone of the control station 1, that is, from outside the control zone of the control station 1.
Execute the registration process according to the registration process flowchart in Figure 2. Note that steps that are the same as those shown in FIG.
The registration request is accepted by the control station 1 in the same way as shown in FIG. 5, and when the registration is completed (step ST
5), from the base station 16 to the base station 15, and from the base station 15
As long as the mobile station 107 moves within the control zone of the control station 1 from the base station 14 to the base station 14, the mobile station 107 remains registered. Also,
The control station 1 appropriately inserts different base station identification numbers into data transmitted via each of the base stations 11 to 16. Here, assuming that a receiver failure occurs in the base station 13, the data from the mobile station 107 will reach the control station 1 immediately after the mobile station 107 enters the communication zone of the base station 13. It disappears. Data from mobile stations 102, 103, and 104 that already exist within the communication zone of base station 13 also no longer reaches control station 1. As a result, control station 1
recognizes that communication with mobile stations 102, 103, 104, and 1o7 has been interrupted, and cancels the registration of these mobile stations. On the other hand, as soon as the mobile stations 102, 103, 104 and 107 also recognize that communication with the control station 1 has been interrupted, they proceed to re-registration processing (step ST8). However, since a receiver failure has occurred in the base station 13, the re-registration process for these mobile stations fails, and each mobile station 102, 103
, 104, and 107 transition to a re-registration timing waiting state (step ST9). Each mobile station 102 that has transitioned to a re-recording timing wait state,
103, 104, and 107 then move and enter the adjacent base station 12 or 14, these base stations 1
As soon as the base station identification number in the data received from 2 or 14 changes and the change is detected (step ST12)
．． In other words, re-registration is performed in the re-registration process start step that starts the re-registration process. In general, trains serving as mobile stations 101 to 107 have an average number of trains per unit time that cross between the communication zones of base stations 11 to 16 due to the spacing before and after trains for safe operation, restrictions on train density due to power supply capacity, etc. Due to the characteristics of doesn't concentrate.

Furthermore, each mobile station can register as soon as it enters an adjacent zone. In addition, in the above embodiment, a method was shown in which a change in the communication zone of the base stations 11 to 16 is determined based on the presence or absence of a change in the base station identification number in the data received from the base stations 11 to 16. After detecting the ground coil installed on the track at the boundary of communication zone ~16 (step ST13). Changes in the communication zones of the base stations 11 to 16 may also be determined. FIG. 3 shows a mobile communication system that detects changes in the communication zones of the base stations 11 to 6 by using such ground sensors 31 to 37, and the registration process is performed as shown in FIG. In the step of starting the re-registration process, the ground sensors 31 to 37
(step ST13). This is followed by re-registration. [Effects of the Invention] As described above, according to the present invention, the V of the mobile station to the control station is
．． When the registration is discarded or the registration fails and the state waits for re-registration timing, the mobile station constantly monitors the base station signal to determine whether there is a change in the communication zone of the two base stations and then detects the change. Since the re-registration process is started at the timing when a failure occurs, all or all of the information registered to the control station may be deleted due to failure of the control station, individual base station failure, or individual line failure between the control station and base stations. Even if a large number of mobile stations are required to re-register due to the discarding of mobile station information, the re-registration timing of these mobile stations is dispersed over time, reducing the load on the control station. This has the effect of avoiding concentration of mobile stations, and allowing immediate re-registration of each mobile station as soon as it enters the communication zone of an unobstructed base station.

[Brief explanation of the drawing]

FIG. 1 is a system diagram showing a mobile communication system implementing a mobile communication system according to an embodiment of the present invention, FIG. 2 is a flowchart showing the procedure of registration processing in this mobile communication system, and FIG. Mobile communication 1 according to other embodiments
FIG. 4 is a flowchart showing the procedure of registration processing in the embodiment of FIG. 3; FIG. 5 is a flowchart showing the procedure of registration processing according to the conventional mobile communication method. It is. 1 is a control station,
11-16 are base stations, and 101 to ↓07 are mobile stations. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Claims] In a mobile communication system that communicates between multiple base stations connected to a control station by a line and a mobile station that moves between the communication zones of these base stations, the mobile station makes a registration request to the base station. a registration request sending step, a retry step of making the registration request a set number of times when a registration response to the registration request is not obtained, and a re-registration timing for placing the registration request that has exceeded the set number of times into a waiting state for re-registration timing. A mobile communication system comprising: a waiting step; and a re-registration processing start step of starting re-registration processing of the registration request in the re-registration timing waiting state at a change timing of the communication zone of the base station.