JPS62199132A - Channel changeover system during communication - Google Patents

Abstract

PURPOSE:To change over a radio channel to a mobile station without disconnection of talking by interrupting a line of a radio station to be used newly into a line of a radio station used at present and a line of a communication opposite party, then switching the radio channel. CONSTITUTION:When a mobile station 1 making correspondence to a communication opposite party 5 via a radio station 2 and a relay station 4' or the like moves and enters the correspondence zone of other radio station 3 from that of the radio station 2, a line 7 used at present by a time division switch 111 and a multi-connection device 112 of the relay station 4' is set to be interrupted to a communication line 10 of the opposite party 5. After the interruption, the lines 9, 10 of the radio station 3 are connected, the radio channel is switched to change over the radio line to the mobile station without disconnection of talking.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a switching method for switching radio channels during communication in mobile communications, and in particular, 1!
! The present invention relates to a switching control method that does not interrupt the communication state when switching line channels.

[Conventional technology]

In mobile communications, if a situation occurs in which a mobile station moves during communication and cannot communicate unless it switches the communication line to another wireless base station (hereinafter also referred to as a wireless station), Perform line switching.

FIG. 1 is a diagram illustrating a method for switching communication lines during communication in conventional mobile communication, and FIG. 2 is a diagram showing a sequence of switching communication lines during communication in conventional mobile communication.

The operation will be explained below with reference to FIG. 1 and tJS2. In addition, in Fig. 2, the wireless station currently communicating (first
The radio station 2) in the figure is indicated as the old radio station, and the radio station with which new communication is to be performed (radio station 3 in FIG. 1) is indicated as the new radio station.

When the mobile station 1 detects a deterioration in the level of radio waves at the wireless station 2 while communicating with the wireless station 2, the wireless station 2 sends a communication line switching request signal 11 to the switching center 4, and transmits the communication line switching request signal 11 to the wireless station 3. Request to switch lines.

After receiving the communication line switching request signal 11, the exchange 4 sends a line setting request signal 12 to the wireless station 3, and after setting up the communication line 9 in the wired section between the exchange 4 and the wireless station 3ffl,
To mobile station 1, through the wireless station 2 that was used until now,
A radio channel switching request signal 13 is sent out to switch the frequency to the mm channel used by the radio station 3.

After receiving the radio channel switching request signal 13, the mobile station 1 switches the radio channel to a new radio channel, and then transmits the radio channel switching completion signal 14 to the new radio channel, so that the signal is sent to the switching center 4 through the radio station 3. Reported.

After receiving the wireless channel switching completion signal 14, the exchange 4 disconnects the line connected to the communication partner 5 to the wired line 9 connected to the new wireless station 3, and then disconnects the line connected to the wireless station 2. The wired line 7 between them is released.

[Problem that the invention seeks to solve]

-1 for communication channel switching control as described above, j
! Considering the situation immediately after the 1m channel is switched to a new wireless channel, the wired line m10 of the communication partner 5 in FIG. Now, the new JL line station 3
Since the communication channel has been switched to the wireless channel used by the mobile station 1, the dark communication path between the communication partner 5 and the mobile station 1 is broken, and the connection of the wired line 10 to the wired line fi9 is lost at the exchange 4. The call will be interrupted until the call is completed.

In this way, when switching wireless channels during a call,
After switching the wireless channel to a new channel at the mobile station, the wired line is switched to the wired line that will be connected to the newly used wireless channel. Therefore, after switching to the new channel at the wireless station, the wired line connection at the exchange is There was a problem in that the communication line was disconnected until the communication was completed, resulting in interruption of communication.

In view of the above-mentioned conventional problems, α, an object of the present invention is to provide a control method in a mobile communication system that does not interrupt a call when the wireless channel is switched during communication between a mobile station and a wireless station. Toshide is here.

[Means for solving problems]

According to the present invention, the above object is achieved by the means described in the claims.

In other words, the present invention provides means (
For example, by installing a multi-connection device (for example, a multi-connection device) and inserting the communication line to the newly used wireless station into the communication line to the currently used wireless station and the communication line to the connected communication partner. The feature is that the mobile station is set to be able to communicate with the communication partner immediately after switching the wireless channel at the station, and then the mobile station switches the wireless channel. This method differs from the conventional technology in which the wireless channel is switched after the mobile station confirms that the wireless channel has been switched from the wired line to the wireless channel.

〔Example〕

FIG. 3 is a block diagram showing an example of the configuration of a multi-connection device installed in a switching center to realize the method of the present invention.
101 is a selection circuit, 102 is a PCM decoder, 103 is an adder, 104 is a PCM encoder, 105 is a selection circuit, 10
6 represents a delay circuit.

Reference marks A and B each indicate the time slot of the signal, Tcl is the time slot in which the voice signal from the radio station currently in use is received, and Tc2 is the time slot in which the voice signal from the radio station to be newly used is received. Tc3 is the time slot containing the voice from the communication partner, Tol is the time slot for the voice signal to the currently used wireless station), Ta2 is the time slot for the voice signal to the newly used wireless station, Ta2 represents the time slot for audio to the communication partner. The range indicated as F is 17 frames.

This time slot is normally assigned l sample values for voice, or 8 bits for a 64 kb/s PCM code.

In FIG. 3, when the PCM signal assigned to the Tzl time slot is input, the selection circuit 101 selects PCM signal.
The signal is input to the CM decoder 102, converted into a linear code, and stored in the adder 103.

When the PCM signal in the time slot Tc2 is input, the selection circuit 101 inputs it to the PCM decoder 102, converts it into a linear code, and inputs it to the adder 103. Adder 103
is the PCM that adds the already stored linearly encoded T<1 and the input linearly encoded Tc2.
The encoder 104 reconverts it into a (/PCM code) and stores it.

It goes without saying that this storage may be performed with the signal before being converted into the PCM1f- number.

When a signal is input in the time slot of TL3, the selection circuit 101 outputs Tc3 to the delay circuit 106 and the selection circuit 105.
lead to.

The selection circuit 105 selects the selection circuit 1 to the time slot of Tol.
TL3 input from 01 to the time slot of Ta2, T<3 stored in the delay circuit 106 to PC to Ta2
The M encoder 104 sequentially outputs the sum of the stored Til and Tt2 voices.

This makes it possible to add the audio from the old radio station and the audio from the new radio station and send it to the communication partner, and to send the communication partner's audio to both the new and new radio stations.

FIG. 4 is a block diagram showing an embodiment of the present invention,
fjS3 This figure shows the configuration of a system in which the multi-connection device explained in FIG. 3 is installed in a switching center to switch communication lines.

In the tjS4 diagram, numbers 1 to 3.5 to 10 are the same as in the PIS1 diagram; 1 is the mobile station, 2 is the old wireless station that has been used for communication, 3 is the new wireless station to which the switch is being made, 4 is the switching center, 5 is the communication partner with which the mobile station is communicating, 6 is the wireless channel that has been used for communication up to now, 7 is the wired line between the wireless station 2 and the switching center 4', and 8 is the newly used 9 is a wired line between the wireless station 3 and the exchange 4', 10 is a wired line between the exchange 4' and the communication partner 5, 111 is a time division switch of the exchange, and 112 is a multi-connection device. It represents.

The tJSs diagram is a sequence diagram showing control of an embodiment of the present invention. The operation will be explained below with reference to FIGS. 4 and 5.

In addition, in PIS 5, the currently communicating radio station (radio station 2 in Fig. 4) is the old radio station, and the newly communicating radio station (radio station 2 in Fig. 4) is the old radio station, as in the case of Fig. 2 above. 3) is displayed as a new jlIi station.

When the wireless station 2 detects a deterioration in the radio wave level of the mobile station 1, it sends a communication line/switching request signal 11 to the switching station 4'.
The switching station 4', which received the communication line switching request code 11 requesting the new wireless station 3 to switch the communication line, sends the communication line setting request code 12 to the new wireless station 3, and switches the wired line to the new wireless station 3. 9 of the multi-connection device 112 through the time division switch 111, and connect the uplink of the wired line #19 to T<2, that is, the line from the wireless station 3 to the exchange 4', to the wired line +li9 to the time slot) Ta2. Connect the downstream side.

Also, at this time, the time division switch is changed for the wired lines 7 and 10 that are already in communication, and the uplink and downlink of the wired line #17 are transferred to the time slots Ttl and Tol of the multi-connection device 1112, and the time slots TL3 and Ta are transferred.
Cable line 10 upstream to 2.

Connect the downstream line. In this state, the voice from the communication partner 5 is distributed to Tol and Ta2 by the multi-connection device, so that the mobile station 1 can listen to it using either wireless channel 6* or 8.

Also, signals from wireless station 2 and wireless station 3 are transmitted through multi-connection 11.
1g1l12 and output to Ta2, the communication partner 5 can listen even if the mobile station 1 uses wireless channel 6 or 8. Thereafter, the exchange 4' sends a radio channel switching signal 14 to the mobile station 1 through the radio station 2 to switch to the radio channel 8.

After receiving the wireless channel switching request signal 14, the mobile station 1 switches the wireless channel to a new wireless channel 8, and then transmits the wireless channel switching completion signal 15 to the switching center 4 through the wireless station 3.
’.

After the mobile station 1 switches the wireless channel, it is connected to the communication partner by the multi-connection device 1112 as described above, so communication can be performed immediately without interruption of the call.

Upon receiving the wireless channel switching completion signal 15, the exchange 4' directly connects the wired lines 9 and 10 using the time division switch 111, sends the communication line release request signal 15 to the wireless station 2, and releases the wired line #[7]. Then, use of the multi-connection device 112 is stopped.

As described above, by simultaneously setting the lines of the wireless station 2 currently being used for communication and the wireless station 3 to be newly used as the communication partner 5 using the multi-connection device, and then switching the wireless channel at the mobile station 1, This eliminates the inconvenience that occurs when a mobile station switches wireless channels as in the past, where the call is interrupted because the line in the wired section is not connected.

〔Effect of the invention〕

As explained above, according to the method of the present invention, the multi-connection device sets the line of a newly used wireless station by interrupting the line of the currently used wireless station and the line of the communication partner, and Regardless of whether you use the wireless channel or the newly switched wireless channel, you can maintain a state where you can talk to the other party when switching the wireless channel, so even after the wireless channel is switched, you can continue communicating without interruption. There is an advantage.

[Brief explanation of drawings]

Figure 1 is a diagram explaining a method of switching communication lines during communication in conventional mobile communications, Figure 2 is a diagram showing a sequence of switching communication lines during communication in conventional mobile communications, and Figure 3 is a multi-connection device. FIG. 4 is a block diagram showing an example of the configuration of the present invention, and FIG. fjS5 is a sequence diagram showing control of the embodiment of the present invention. 1...Mobile station, 2.3...
Radio station, 4.4' ... Switching station, 5 ...
...Communication partner, 6.8 ...Wireless channel,
7,9.10... Wired line, 101
... Selection circuit, 102 ... PCM decoder, 103 ... Adder, 104 ・
... PCM encoder, 105 ... selection circuit, 106 - ... delay circuit, 111 ...
・・・Time division switch, 112 ・・・Multi connection device

Claims (2)

[Claims] (1) Consisting of multiple radio base stations, a switching center connected to each radio base station via a communication line, and a mobile station connected to one of the radio base stations via a radio line, the mobile station When you move to the wireless zone of another wireless base station while communicating with a wireless base station, you can switch to the wireless line with the new wireless base station and change the communication route between the switching center and the wireless base station to the wireless zone of the new wireless base station. In a mobile communication system in which communication is continued by switching to a communication line between a base station and a switching center, the switching center switches the communication line between the switching center and a wireless base station to the communication line between the switching center and another wireless base station. A means for interrupting the communication line between the wireless base station and the switching center is provided, and when the mobile station moves to the wireless zone of another wireless base station, the means allows the communication line between the wireless base station and the switching center that has been used until then to be interrupted. After interrupting the communication line between the mobile station and the switching center to maintain the communication status between both wireless base stations and the mobile station's communication partner, the communication path between the mobile station and the wireless base station is established between the mobile station and the new wireless base station. A channel switching method during communication characterized by switching to a wireless line with a base station. (2) Means for interrupting the communication line between the switching center and another wireless base station into the communication line between the switching center and the wireless base station is to 2. The channel switching system during communication according to claim 1, wherein signals are simultaneously sent to each line of the radio base stations, and the signals on the lines from both radio base stations are summed at the switching station.