JP3055740B2 - Channel switching method during mobile communication - Google Patents

Abstract

PURPOSE:To facilitate communication consecution (channel switching) processing through a common control channel of a transfer destination zone. CONSTITUTION:When a mobile station 13 starts communication through a base station 121 of a zone 111, a base station stores a call management number to a home memory 22 by using a mobile station number as an address. When the mobile station enters a zone 11. and makes a re-connection request through a common control channel, a controller 162 receives the request through a base station 122 and accesses a home memory device 17 based on the mobile station number via an exchange 151 to recognize a resident zone 111 and a call management number and makes a switching request to a controller 161 of the zone 111 together with the call management number. The controller 161 makes a switching request to the exchange 151 similarly to the case with usual channel switching based on the call management number. The succeeding processing is processed similarly to the case with a conventional method and a new channel is designated to the mobile station via a base station 122.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is applied to a mobile communication system such as a car telephone, a portable telephone, a cordless telephone, etc., and a service area is constituted by a plurality of zones. The present invention relates to a communication channel switching method of mobile communication in which a communication channel is switched by transmitting and receiving a control signal to and from a switching destination base station.

[0002]

2. Description of the Related Art In a conventional FDMA system mobile phone,
When communication is going to be difficult due to crossing the zone boundary during communication, the base station requests channel switching using the communication channel in use, and the base side adjusts the reception level of radio waves from the mobile station. The zone is detected, the destination zone is determined, a free communication channel in the zone is searched, and this is notified to the mobile station to switch to the new communication channel. Failure to switch the communication channel or rapid deterioration of the quality of the wireless channel may cause the wireless channel to be cut off before performing the channel switching during communication. I needed to.

[0003]

When a channel switching request is made in the office cordless telephone system, the mobile terminal number is sequentially read out from each call management number in the call management table, and the mobile terminal number is searched for. Since information necessary for call processing obtained from the number and information on the old line are obtained, the search processing generally has a large amount of processing, has a disadvantage in that the control ability is squeezed, and the processing takes time. This method can be used with a relatively small system such as a cordless telephone system at a business office. Since the number of calls is large, it is difficult to specify the old line in the search processing.

[0004] In addition, due to the system configuration, it is common that control devices for managing communication calls are distributed and arranged, and it is necessary to search for such control devices, and an old line is specified by a search process. In general, it is difficult to perform communication continuation (switching the channel during communication) by the conventional method using the control channel of the movement destination zone due to switching failure due to processing power and processing time. There is.

An object of the present invention is to provide a method of switching channels during communication triggered by access to a control channel of a switching destination zone, which is easily applicable to a relatively large-scale mobile communication system. .

[0006]

SUMMARY OF THE INVENTION Mobile communication according to the present invention
The channel switching method during communication of at least one
Service at least one switching equipment
Rearrange the zone where the mobile station communicates during communication.
When switching, the base station of the destination zone and the control signal
Mobile communication that switches between communication channels by giving and receiving
Communication channel switching method after setting the communication channel
In accordance with the call management number assigned to each call,
A first table storing call information required for processing the call.
Are provided in the base station and the switching device, respectively.
Established in service area to identify mobile station or subscriber
To indicate the zone in which the mobile station is located
The communication table is stored in the second table storing the zone numbers.
After the setting, the call management number is assigned to the mobile station or subscriber.
Stored in correspondence with the specified number when switching channels
Channel from the mobile station to the base station in the switching destination zone.
A signal requesting replacement is transmitted, and the switching device
Included in the switching request signal received from the base station.
Using the number that identifies the mobile station or subscriber
2 to access the table of the mobile station and
Obtain call management numbers and use these numbers to determine the zone
Access the first table of each of the base station and the switching equipment
And obtains the call information necessary to process the call,
Channel switching is performed based on the information.

[0007]

FIG. 1 shows the configuration of a mobile communication system to which the present invention is applied. Zone 11 _1, 11 _2, 11 _3, the service area is constituted by ..., each zone 11 _1, 11
_2, 11 _3, the base station 12 ₁ ..., the 12 _2, 12 _3, ... is provided, the mobile station 13 to move each zone _{11 i (i = 1,2, ...} ) base station of the zone 11 _i to communicate with the 12 _i. Base stations 12 ₁ and 12 ₂ are communication lines 14 ₁ and 14 ₂
Is connected to the switching device 15 ₁ via the base station 12 ₃ is connected to the switching device 15 ₂ through a communication line 14 _3, the control device 16 _1, 16 ₂ is the base station 12 _1, respectively, 12
_2, are connected through respective control lines to the switching device 15 _1, the control device 16 ₃ is the base station 12 ₃ and the exchange device 15
_{And 2} are connected via control lines. The switching devices 15 ₁ and 15 ₂ are connected to the home memory device 17 and the network 18.

The control device 16 _i and the switching device 15 are provided with call management tables 19 and 21 for each zone, respectively.
A call management number is assigned for each call, call information necessary for processing the call is stored, and the base side performs processing for the call using this call management number. In the home memory device 17, in the management table 22, the subscriber number or the mobile station number is used as an address, and the subscriber data (the number of the zone where the user is located, the information indicating the service being received, etc.) related to the subscriber (mobile station). ) Is stored.

The operation of the embodiment of the present invention will be described with reference to FIGS. When the mobile station 13 is in a state of communicating through the base station 12 _1, the control device 16 ₁ that controls the base station 12 ₁ in this invention, for identification of the communication call between the exchange unit 15 ₁ Exchange number 15 ₁
Is stored in the area of the home memory device 17 for the mobile station 13 via the. This call management number is a number that can be used in a control device or a switching device to access information related to the call using the number as an address. A method of assigning a number every time a communication call occurs, a method of substituting with a number of a communication line, etc. The present invention can be applied to any of these methods. In storing the call management number in the home memory device 17, the subscriber number of the mobile station or the mobile station number is stored so as to be accessible as an address. This storage is stored in the management table 22.
As shown in (1), it is usually sufficient to treat the same as the subscriber data accessed based on the subscriber number. The access to the subscriber data may be realized by a method similar to a method adopted in a normal system, which is an essential function in a car telephone system.

[0010] The base station 12 the mobile station 13 from the base station 12 _{1
If 2} is moved to the zone 11 ₂ covering, in the channel switching general communication will be carried out switch to specify a switching destination of the radio channel in transmission and reception of signals between the base station 12 _1, common channel switch The switching method according to the present invention is applied to the case where the wireless channel is cut off before the general channel switching during communication is performed due to rapid wireless channel quality deterioration due to a failure in wireless channel quality. That common channel switch to or failure, due to rapid radio channel quality degradation, when the communication with the base station 12 ₁ becomes impossible, the mobile station 13, the same operation as the frequency scanning performed in a normal standby state To select a communicable zone. By the selection, the mobile station 13 is set to the zone 1
1 ₂ to the base station 12 ₂ to cover and transmits a reconnection request signal including the mobile station ID by using a common control channel. Base station 12 ₂ controller 16 ₂ which has received the reconnection request signal via accesses the home memory device 17 through the switching device 15 ₁ on the basis of the corresponding mobile station number included in the reconnection request signal Then, the call management number and the zone number of the switching source are obtained. Since this by switching source zone 11 ₁ can be identified, the base station 1 that covers the zone 11 ₁
A request signal for activating the channel switching is sent to the home memory device 17 from the control device 16 ₁ controlling the 2 _1.
And sends it with the call management number obtained from. The switching source controller 16 ₁ stores the transmitted call management number in the switching device 15.
Send to ₁ to request communication channel switching. Thus much like the communicating channel switching in general, changer 15 ₁ sets the idle communication channel zone 11 _2,
Sent to the control unit 16 _2, the control device 16 ₂ base station 12 ₂
Of the base station 12 ₂
By specifying the mobile station 13 a radio channel for communication from the base station 12 ₂ and the mobile station 13 moves to a state of communicating and releases the communication line of the base station 12 _1.

According to the present invention, the zone number of the switching source and the call management number in the controlling device which is controlling can be easily known by accessing the home memory device 17, and the contents of the call management table are sequentially read out. There is no need to search for the call management number of the mobile station number, and channel switching can be realized by simple processing. As understood from the sequence shown in FIG. 2, the sequence after transmitting the channel switching activation to the control device 16 ₁ is almost the same as the general channel switching, and the base station transmitting the radio channel designation signal is in general channel switching, while a switching source base station 12 _1, in this embodiment, it is possible to point at which the switching destination base station 12 ₂ is different only. Therefore, in order to realize a system having a plurality of channel switching procedures of reconnection-type channel switching in addition to general channel switching,
Since the procedures are similar, the processing can be shared and the system can be prevented from becoming complicated.

The call management number is a signal transmitted and received between the control device and the switching equipment. In some cases, the call management number refers to a number table to obtain an address, and the address accesses the call information in the call management table. Therefore, instead of the call management number stored in the home memory device 17, an address number or the like obtained from the number table and used in the internal processing of the control device or the switching device may be stored. Further, even when the control device and the switching device are configured as one device, the management number used in the internal processing may be treated as the call management number.

In the above description, a case has been described in which the control device controls one base station and one base station controls one zone. However, one control device controls a plurality of base stations, and one base station further controls one zone. Even when a plurality of zones are provided, the present invention can be applied by providing a table for each zone. Since the zone number is a number that can specify the zone in the service area, the number of the switching device or the number of the control device may be given as necessary. If the call management is collectively managed for each device, the zone number may be interpreted as a device number.

When there are a plurality of types of wireless channels, such as those having different transmission speeds, dedicated to facsimile, and dedicated to speech, when selecting a wireless channel after a reconnection request, it is necessary to select the same type of channel as before switching. is there. Therefore, by storing information on the type of the wireless channel being used, that is, information on the line being used, together with the call management number and the like in the home memory device 17, it is not necessary to wait for access to the switching source control device. Then, it is possible to proceed to the process of selecting a channel when the home memory device is accessed.

Although the case where the mobile station moves and shifts to a zone has been described, the present invention can be applied to a case where interference is detected and channels are switched within the same zone in order to avoid the interference.

[0016]

As described above, according to the present invention, since the number corresponding to the call management number during communication is stored in, for example, the home memory device, when a request to switch the channel during communication is received. By accessing the home memory device with the requesting mobile station or subscriber number, the number corresponding to the call management number can be easily known, and the channel switching process can be performed without the need for the search process. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration example of a mobile communication system to which the present invention is applied.

FIG. 2 is a diagram showing a control sequence in the embodiment of the present invention.

Continuation of front page (72) Inventor Yasuyuki Watanabe 2-10-1 Toranomon, Minato-ku, Tokyo Inside NTT Mobile Communication Network Co., Ltd. (56) References JP-A-5-218953 (JP, A) (58) Fields surveyed (Int.Cl. ⁷ , DB name) H04B ^7/ 24-7/26 H04Q ⁷ /06-7/38

Claims (2)

(57) [Claims] Claims: 1. A small number of devices accommodating at least one base station.
At least one switching device constitutes a service area, and when switching a zone in which a mobile station communicates during communication, a mobile station exchanges a control signal with a base station in a switching destination zone to switch a communication channel. In the communication switching method, a call management assigned to each call after setting a communication channel.
Call information needed to process the call
The base station and the switching device store the stored first table.
, And located in the service area to identify the mobile station or subscriber
To indicate the zone in which the mobile station is located
The communication table is stored in the second table storing the zone numbers.
After the setting, the call management number is assigned to the mobile station or subscriber.
When the channel is switched, the mobile station transmits a signal requesting channel switching to the base station in the switching destination zone, and the switching device transmits the signal to the switching request signal received from the base station. the mobile station or subscriber is included with the number specifying its accesses said second table
Obtain the mobile station's zone number and call management number, and enter these numbers
Each of the above-mentioned first of the zone base station and the switching device before movement is used.
Calls required to process the call by accessing the table
A method of switching channels during mobile communication, comprising obtaining information and performing channel switching based on the call information . 2. The second table stores information on an in-use line together with a number corresponding to the call management number, and uses the stored information on the in-use line when a channel is selected. 2. The method according to claim 1, wherein
The method for switching a channel during communication of mobile communication according to the above.