JP2690547B2 - Data delay method in mobile communication - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a channel switching control signal from a base station to a switch when a channel is switched according to a movement of a wireless zone of a mobile station in a mobile communication system. The present invention relates to a data delay method in which communication data is delayed at a base station in order to reduce communication interruption time corresponding to transmission time and its processing time.

[Problems to be solved by conventional technology and invention]

 FIG. 3 shows a conventional mobile communication system configuration.

1 is a mobile device, 2-1, 2-2 is a base station, 3 is an exchange, 4
Is a channel device, 5 is an exchange control device, 6-1 and 6-2 are receivers, 7-1 and 7-2 are base station control devices, 8-1 and 8-2 are data lines, and 9 is a control line. Is.

In FIG. 3, the communication data from the mobile device 1 is the base station 2-
1 is received by the receiver 6-1 and the data line 8
It is sent to the exchange 3 through -1.

In FIG. 3, the channel switching control method when the mobile device 1 moves from the radio zone of the base station 2-1 to the radio zone of the base station 2-2 will be described below.

First, in the destination base station 2-2, the receiver 6-2 monitors the presence or absence of communication data from the mobile device 1. When the receiver 6-2 detects the communication data from the mobile device 1, the communication data is sent to the exchange 3 through the data line 8-2 and the base station controller 7-2 is notified that the channel switching has been executed. To do. Base station control device 7-2
Notifies the exchange control device 5 of the exchange 3 that the channel switching is completed through the control line 9. The exchange control device 5 changes the call path of the call path device 4 in order to switch the data line for receiving the communication data from the mobile device 1 from the data line 8-1 to the data line 8-2.

As described above, in the conventional mobile communication system, at the time of channel switching, only the time from the detection of communication data from the mobile device at the base station of the destination of the mobile device to the switching of the communication path of the communication path device of the exchange. There was a drawback that communication was lost.

An object of the present invention is to provide a data delay method that solves the drawback of the conventional method that communication is interrupted only for the time from when the base station detects that the mobile station has completed channel switching until the switch changes the communication path. To provide.

[Means for solving the problem]

According to the present invention, the above objects are achieved by the means as set forth in the claims.

That is, the present invention divides a communication service area into a plurality of wireless zones, deploys a base station in each wireless zone, connects a mobile device and a base station with a wireless line (channel), and connects the base station and the exchange. Connected by a data line that carries communication data from the mobile device and a control line that carries control data from the base station, and when switching channels, the base station detects that the mobile device has completed channel switching, and the base station In the mobile communication system in which the exchange notifies the exchange through the control line, and the exchange changes the internal communication path in response to the channel switching, after delaying the communication data received from the mobile station to the base station for a predetermined period of time. , A means for relaying to the exchange through the data line, and for the fixed time, the exchange switches the internal communication path after the channel switching is detected by the base station. A data delay for Mobile communication sets the time equivalent to the time required until further.

[Action]

According to the present invention, the communication data from the mobile station is delayed by the base station for a time corresponding to the time from when the base station detects that the mobile station has completed the channel switching until when the exchange changes the communication path.

This is different from the conventional technique in that the base station temporarily stores communication data from the mobile station, delays the communication data for a predetermined time, and then transmits the data to the exchange.

〔Example〕

FIG. 1 shows a configuration example of a mobile communication system for realizing the data delay method of the present invention.

In FIG. 1, 10-1 and 10-2 are data delay devices, and the other 1-9 are the same as those in FIG.

In FIG. 1, communication data from the mobile station 1 is received by a receiver 6-1 in a base station 2-1 and accumulated in a data delay device 10-1 for a certain period of time and then sent to a switch through a data line 8-1. To be

In FIG. 1, the channel switching control method when the mobile device 1 moves from the wireless zone of the base station 2-1 to the wireless zone of the base station 2-2 is as follows. Is stored in the data delay device 10-2 for a certain period of time and then transmitted to the exchange through the data line 8-2.

 FIG. 2 shows the configuration of the data delay devices 10-1 and 10-2.

In the figure, 11 is a data buffer, 12 is a write counter, 13 is a read counter, 14 is a comparator, and 15 is an AN.
It is a D circuit.

The communication data of the mobile device 1 received by the receivers 6-1 and 6-2 is sequentially written from the start address of the data buffer 11 by the write counter 12 and by the read counter 13.
The data is sequentially read from the start address of the data buffer 11.

The counter values of the write counter 12 and the read counter 13 are counted up by the external clock CK. In order to delay the data, it is necessary to control the data buffer 11 to store the data for a certain period of time and then read the data. This function is realized by the comparator 14 and the AND circuit 15. The comparator 14 sets the reference value to the input A, and outputs the logical value "1" as the output C when the input B exceeds the reference value.

Further, the AND circuit 15 allows the clock CK and the comparator 1
The output of 4 is ANDed and then input to the read counter 13.

Now, assume that the clock interval is T and the time you want to delay is nT.
Then, the base station control devices 7-1 and 7-2 set n as the reference value of the comparator 14. By doing so, the comparator 14 sets the output to "1" only after the clock CK is input.

Therefore, the clock CK input to the read counter 13 is
Since it is input by the AND circuit 15 with a delay of n clocks, the counter value of the read counter 13 is always smaller than the counter value of the write counter 12 by n. By doing so, the communication data from the mobile device is read out after accumulating nT in the data buffer 11.

As the delay amount nT of the data delay devices 10-1 and 10-2, when the receivers 6-1 and 6-2 receive the communication data from the mobile device at the time of channel switching, the call path of the call path device 4 of the exchange 3 A time almost equal to the time Tc before changing is set in the data delay devices of all base stations. By doing so, the communication data from the mobile station 1 is sent to the exchange 3 with a delay of nT at the base station.
When moving from the wireless zone to the wireless zone of the base station 2-2, the communication data corresponding to the delay time nT in the channel switching control time Tc is transmitted from the base station 2-1 and then the base station 2-2. It will be sent from 2-2.

At the channel switching control time Tc, the communication path device 4 of the exchange 3 is still set up with a path so as to receive communication data from the base station 2-1. Therefore, at this delay time nT, communication is not interrupted and communication is continued. Only the time difference between the delay time nT and the channel switching control time Tc is interrupted.

As described above, according to the present invention, the communication is interrupted for the channel switching time Tc in the conventional technique, but the interruption time can be reduced to the time | Tc−nT |.

〔The invention's effect〕

As described above, in the present invention, the communication data from the mobile device is transmitted for the time corresponding to the time from when the base station detects that the mobile device has completed the channel switching to when the exchange changes the communication path. Because of the delay at the base station, the time when the communication data after channel switching arrives at the exchange and the time when the exchange changes the communication path can be made to be almost the same, and the communication interruption time at the time of channel switching compared to the conventional technology. Has the advantage that it can be shortened.

The channel switching control time can be almost estimated in advance by the system configuration, the channel switching method, etc., so the data delay time may be initialized at the time of system startup.

Also, when a communication data signal processing device such as a voice codec is installed in the base station, the signal processing device itself delays several tens of milliseconds, which is about the same as the channel switching control time, so the signal processing device serves as a data delay device. Since it has the above function, it is not necessary to install a data delay device in particular, and in reality, the base station can be configured by only the originally necessary device.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a mobile communication system having a data delay function of the present invention, FIG. 2 is a diagram showing a configuration of a data delay device for realizing the data delay function of the present invention, and FIG. 3 is a conventional mobile communication system. It is a figure which shows a system structure. 1 ... Mobile device, 2-1, 2-2 ... Base station, 3 ... Exchange device, 4 ... Call path device, 5 ... Exchange device control device, 6-1,
6-2 ... Receiver, 7-1, 7-2 ... Base station controller, 8
-1,8-2 ... Data line, 9 ... Control line, 10-1,10
-2 ... data delay device, 11 ... data buffer, 12 ...
… Write counter, 13 …… Read counter, 14 …… Comparator, 15 …… AND circuit

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Junki Shinagawa 1-1-6 Uchisaiwaicho, Chiyoda-ku, Tokyo Inside Nippon Telegraph and Telephone Corporation (56) Reference JP-A-59-212040 (JP, A) JP JP-A-63-226134 (JP, A) JP-A-62-159529 (JP, A) JP-A-61-171269 (JP, A)

Claims (1)

(57) [Claims] 1. A communication service area is divided into a plurality of wireless zones, a base station is provided in each wireless zone, a mobile unit and a base station are connected by a wireless line (channel), and a base station and an exchange are moved. Connected by a data line carrying communication data from a mobile station and a control line carrying control data from a base station, and when switching channels, the base station detects that the mobile station has completed channel switching, and the base station In a mobile communication system in which the exchange notifies the exchange through a control line and the exchange changes the internal communication path in response to channel switching, after delaying the communication data received from the mobile station to the base station for a preset time, A means for relaying to the exchange through the data line is provided, and the exchange changes the internal communication path after the channel switching is detected by the base station for the above-mentioned fixed time. A data delay method in mobile communication, characterized in that a time equivalent to the time required for setting is set.