JPH09205679A - Communication line setting method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the degradation of transmission rate and transmission quality by eliminating hand-over with the cell selection method in which a call type or the like is used for cell selection criterion in a mobile communication system of multi-layer constitution. SOLUTION: Each program and a table are stored in a memory 103. A cell selection transmission section 130 is constituted of a cell selection program 131 for realizing each selection processing such as incoming outgoing cell, a cell switching program 132 corresponding to a busy state, and a cell selection table 133. Then the cell selection table 133 decides a cell to be selected based on the combination of each information. When a caller mobile terminal equipment 100 sends a call class and a line use time or the like, the conditions above are arranged on the cell selection table 133. Thus, an optimum cell class is selected and the same cell class is sent to the mobile terminal equipment 100 to start line connection processing with the radio base station constituting the same cell class.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-layer cell system in which radio zones of different sizes are layered, and a radio base station that covers a radio zone of an optimum size is selected for each call to establish a communication line. The present invention relates to a communication line setting method for a mobile communication system to be set.

[0002]

2. Description of the Related Art Conventionally, a terminal in a mobile communication system has prescribed rules, conditions, and conditions defined by a standardization organization in a wireless interface with a wireless base station to which the terminal is connected.
It satisfies the rules and conditions set by the operator who operates the system. In addition, a general configuration inside the terminal includes an antenna unit, an RF unit, a modulation / demodulation unit, a transmission / reception control unit, a voice processing unit, a CPU, a memory, and a man-machine interface unit.

For example, the standard established by a standard organization is as follows:
RCR STD-27 (Japan Radio Industry Association Digital Car Phone System Standard), RCR-28
(Company Radio Industry Association Second Generation Cordless Telephone System Standard). RCR STD-27 is a standard that defines a digital cellular radio interface, a terminal, and a base station. RCR STD-28 is PHS
It is a standard that defines a wireless interface (personal handy phone system), terminals, and base stations. Also,
Regarding the internal configuration of the terminal, as an example of a digital cellular terminal, in "easy digital mobile communication", an antenna,
Transmitter / receiver, receiver, modulator / demodulator, power amplifier, frequency synthesizer, CODEC, controller, microphone, speaker,
The display operation unit is listed. In addition, in the “friendly personal handy phone”, the internal configuration of the PHS terminal includes an antenna unit, a modulation / demodulation unit, a voice processing unit (voice CODE).
C), a TDMA-TDD processing unit (control unit), a CPU, a memory, an input / output device, and a quality monitoring unit.

[0004]

In the above-mentioned prior art, no distinction is made between calls such as voice communication, image communication and data communication, which have completely different transmission rates and hold times.
Therefore, for example, when performing data communication in a high traffic area, if a cell with a small cell radius is selected by the conventional cell selection method, handover will occur frequently. Since the transfer is interrupted, the transmission rate and the transmission quality are significantly reduced. Also, when performing voice communication that has a short hold time and allows a slight decrease in quality, if the terminal is moving at high speed and a large cell is selected using the conventional technique 3, the hold time and call type are changed. Regardless of the number of calls, which are moving at high speed, the calls are concentrated in a large cell base station with a small number of lines. Furthermore, if there is no available line in the base station selected at the time of making a call in the above-mentioned conventional technology, connection is impossible, and if there is no available line in the wireless base station of the same cell type when switching channels during a call, switch back Will increase the deterioration of line quality,
Furthermore, it will be a forced disconnection.

An object of the present invention is, in a multi-layer cell system, based on information about the type of a call, the moving speed of a terminal, or the expected line usage time during data communication.
It is to provide a method for selecting the most suitable cell type to be connected to a terminal and setting a communication line.

Another object of the present invention is to connect a line to a radio base station forming a cell determined by using the above-mentioned cell selection method or an existing cell selection method, when the line is empty. It is to provide a method of selecting a cell type of another layer and setting a communication line.

Further, another object of the present invention is that, when channel switching is required during line connection and there is no free line in the radio base station of the same cell type, another cell type (other It is to provide a method of selecting a cell of a layer) and setting a communication line.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows a PS with a cell selection device of the present invention.
It is a schematic diagram showing an internal configuration of (Personal Station) 100. PS100 with cell selection device
An RF unit 110 for transmitting and receiving radio waves, a wireless line control unit 116 for controlling a wireless line between PS-BS or PS-satellite, each program, a storage unit 103 such as a memory for storing and storing data, based on each of the above programs CPU 102 for performing various processes, a keypad input device for inputting a telephone number, a man-machine interface unit 104 for controlling display and the like, and a PC interface unit for controlling connection with each terminal such as PC / PDA. It is composed of 105 and the like.

The RF unit 110 is a large cell system RF unit 1 for communicating with a radio base station (BS) 340 covering a large cell, a communication satellite, and the like.
12, RF unit 113 for medium cell system, and R for small cell system for communicating with a radio base station that covers a small cell
The F unit 112, the common RF unit 111 which is a common function unit for each cell system, and the GPS used for PS position measurement.
(Global Positioning System
m) GPS RF unit 1 for receiving positioning radio waves from satellites
It is composed of fifteen or the like.

Each program and table are stored in the memory 103. As a concrete program,
Performs communication control between the PS integrated control program 120 that controls the entire PS, such as process start / end instruction of the general program / data transmission / reception control between processes, and each BS that services the large cell, medium cell, and small cell. Large cell system control program 121, medium cell system control program 122, small cell system control program 123
And a cell selection function unit 130 that selects a cell or a BS for the PS to communicate with, and a moving speed detection program that performs a process of obtaining the moving speed of the PS from terminal point information (latitude / longitude information) obtained by using GPS. 134 and GPS
There is a GPS control program 135 for activating / controlling. These programs may be physically stored in a plurality of memories. The moving speed detection program 134 does not necessarily need to use GPS, and may be any program as long as it can estimate or specify the moving speed of the terminal.

Further, the cell selection function section 130 is selected by a cell selection program (for PS) 131 that realizes each cell selection process at the time of making and receiving calls, a BUSY-time compatible cell switching program 1132, and a cell selection table 133. Perform processing.

FIG. 2 is a schematic diagram of the PS100 shown in FIG.
3 is a diagram showing a machine interface unit 104. FIG. PS
Man-machine interface section (hereinafter referred to as MM
Part I. ) 104 is composed of an input unit for the subscriber who is the user of the PS to input an instruction to the PS, and an output unit for the PS to output the PS status or information to the subscriber. More specifically, the man-machine interface unit 104
Is an image-receiving camera 201 used during a videophone call, a speaker 202 which is a receiver, and a microphone 211 which is a transmitter.
And a display 203 for displaying images and characters
And keypad 207 for entering the called number and setting each function
And a call type selection button 204 used when the user specifies a call type such as "voice". Further, in the cell selection device 360 or the cell selection function-equipped PS, a "charge priority" 208 button for instructing to switch cells by prioritizing the call charge when requesting cell switch at the time of the wireless line BUSY, and more call quality It is equipped with a "quality priority" 209 button for instructing to perform cell switching by giving priority to a cell system with a high priority, and a priority method can be set in advance before communication.

FIG. 3 shows the configuration of a mobile communication network system to which the PS of the present invention is applied.

This network includes a plurality of mobile terminals 10.
0,300,302 etc. are accommodated. The small cell radio base station 320 uses the small cell 321 as a service area. The medium cell radio base station 330 uses a medium cell 331 composed of a plurality of small cells 321 as a service area. The large cell radio base station 340 uses a large cell 341 including a plurality of medium cells 331 as a service area. The small cell base station control station (hereinafter, referred to as small cell BSC) 322 accommodates a plurality of small cell BSs 320. The medium cell base station controller (hereinafter, referred to as medium cell BSC) 332 accommodates a plurality of medium cell BSs 330. The large cell base station control station (hereinafter, referred to as large cell BSC) 342 accommodates a plurality of large cell BSs 340. Each of these BSCs is connected to a mobile communication switching center (hereinafter referred to as MSC) 350. Further, the MSC 350 has a cell selection device 36.
0 and a position information database (hereinafter referred to as position information DB). This MSC350 is a gateway exchange 3
Via 80, it is connected to the other mobile communication network 390 and the fixed communication network 391 accommodating the fixed telephone 303 to perform call switching connection.

The cell selection device 360 selects a cell used for communication between a PS and a BS that does not have a cell selection function, based on information sent from the PS.

The large cell 341 of the mobile communication network shown in FIG. 3 may be covered by a communication satellite. The large-cell BSC 342 includes an earth station 243, and this earth station communicates with the communication satellite 240 via a satellite line to perform satellite relay and connect with a wireless terminal.

FIG. 4 shows a PS cell selection program 131.
It is the figure which showed the detailed structure inside. Cell selection program 1
Reference numeral 31 is composed of a calling-side cell selection processing program 401 used when making a call at a terminal with a cell selection function and a called-side cell selection processing program 402 used when making a call at a cell selection function. It A calling-side cell selection processing program 401 used at the time of making a call at the cell selection equipped terminal is a program for determining an optimum cell type as a connection destination at the time of making a call. Destination side PS100 is destination side B
When the call setup request message sent by S is received, the receiving BS
It is determined whether or not the cell type is the optimum cell type, and if it is not the optimum cell type, the destination cell selection processing program 402 is activated to switch the cell. By the way, the cell selection at the time of the incoming call can be performed by the radio base station or the cell selection device on the network side.

FIG. 5 is an example showing a schematic logical configuration of the cell selection table 133.

During cell selection, PS100 to BS, B
The information provided to the cell selection device via the SC and MSC includes, for example, call type 501, expected line usage time 505, terminal moving speed 508, and the like. The call type 501 indicates the content of information sent by communication, and is specifically “voice” 502 / “image” 503 / “data” 504 or the like. The expected line usage time 505 indicates a time estimated in advance before communication about the time that the communication line will be occupied, and specifically, "short time" 507 / "long time".
It is class information such as 506 or the actual expected time such as "33 minutes". The terminal moving speed 508 means the moving speed of the terminal, which is “high speed” 510 / “low speed”.
Speed class information such as 509, or "100 km /
It is provided at the actual speed of movement, such as "h". The cell selection table 306 has a configuration for determining a cell to be selected based on the combination of the above information.

Here, cell selection using the cell selection table 306 will be described with a specific example. Now, "data" 504 as the call type 501 and expected line usage time 50 from the originating PS 100 via the BS, BSC, and MSC.
Consider a case where "long time" 506 is transmitted as 5, and "high speed" 510 is transmitted as the terminal moving speed. When this condition is arranged on the cell selection table 510 in FIG. 5, the cell type existing at the intersection of “data” 504, “long time” 506 and “high speed” 510 is “large cell”, and this “large cell” Is selected.

FIG. 6 is a diagram showing a call type input sequence such as data at the time of making a call in the PS 100.

The user of the PS 100 who wants to initiate a call inputs a telephone number such as the terminal number of the terminating PS from the keypad (602). Next, the priority setting button 208,
The priority setting is input from 209 (603). In addition, PC
Alternatively, when a PDA or the like is connected and data communication is performed,
The terminal number of the destination PS and the priority setting information can be transmitted from the PC or PDA side. Next, it is identified whether or not there is a call type input (input from the call type selection button) (604). In the process of 604, if the call type is input (605), the input call type is set as the type of the call to be made. On the other hand, in the processing of 604,
When the call type is not input, the default call type preset for each PS is set as the type of the call to be made (607). In addition, PC or P
When DA or the like is connected, the call type may be notified from these devices. Finally, the user presses the call button
Press (call button) to start calling (608). Further, when the PS is connected to the PC or PDA, these devices may instruct calling.

FIG. 7 shows a processing flow chart of the cell selection on the calling side of the cell selection device 360. Upon receiving the calling side cell selection process execution request message from the MSC 350, the cell selection device 360 activates the calling side cell selection process (701). In the calling-side cell selection process, first, the call type 501 (“voice”) included in the cell-selection request message transmitted from the calling-side PS via the BS-BSC-MSC.
/ "Image" / "Data" etc. ) Is identified (70
2) Store the identified call type information in the memory. Here, the expected call time 505 along with the call type “data” 504
If a "long time" / "short time" class or a numerical value such as "25 minutes" is also transmitted from the originating PS, the line usage time 505 is also stored in the memory. Similarly, when the terminal moving speed 508 (“low speed” / “high speed” speed class or a numerical value such as “60 km” etc.) is also transmitted from the originating PS, the terminal moving speed 508 is identified. (1312) The same information is also stored in the memory. Next, each of the above information stored in the memory of the cell selection device is assigned to the cell selection table 580, and the best cell type to be connected by the originating PS is selected (704). Next, it is confirmed whether or not the cell type of the BS transmitted from the originating BS matches the selected best cell type (705), and if they do not match, the originating PS
Cell switching (BS switching) is instructed (51
7). Here, the cell type designated as the switching destination is 704
The best cell type selected by the above process is used. A cell switching required message for instructing cell type switching including the cell type of the switching destination is generated, a cell selection response message is transmitted from the network side interface unit 502 to the MSC (708), and the process is terminated (709).

On the other hand, when the cell type of the BS connected to the originating PS matches the best cell type selected in the process of 704, the originating PS is instructed not to switch cells. (706). In this processing, a cell switching unnecessary message instructing cell switching unnecessary is generated, transmitted from the network side interface unit to the MSC (708), and the processing is terminated (709).

FIG. 8 shows a processing flow chart of the cell selection device when receiving a call. Here, the incoming call processing to the wireless terminal (PS) under the service of the multi-layer system of the present application will be described. Especially, in this system, the point is how to select the cell to be used for incoming calls.

When the cell selection device 360 receives the call-destination cell selection processing execution request message from the MSC 350, it performs the call-destination cell selection processing (801).

In the destination cell selection processing, first, a cell selection request message transmitted from the originating PS via the originating BS-the originating BSC-the originating MSC-the terminating MSC is analyzed and the call type 501 is included. It is determined whether or not (802).

When the cell type request message includes the call type 501, the call type is analyzed (1311),
The call type information found by the analysis is stored in the memory.
In addition, the call type “data” 504 and the expected line time 50
When 5 is also transmitted from the originating PS, the line usage time is also stored in the memory. The terminal moving speed of the terminating side PS is unknown unless the position registration side constantly manages the position and moving speed of the terminal, and therefore the moving speed of the terminal must be calculated. As an example of calculating the moving speed, the receiving side including the position information of the destination PS included in the cell selection request message transmitted from the MSC is received, and the destination side is received based on the received destination PS position information. Estimate the moving speed of the terminal. In this way, the destination PS movement speed estimation processing (804) is performed and stored in the arrival side PS movement speed memory. Next, each of the above information stored in the memory 503 is assigned to the cell selection table 580 and the best cell type to be connected by the destination PS is selected (805). Subsequently, a cell selection response message including the cell type selected by the processing of 805 is generated and transmitted to the MSC (806), and the processing ends (8
07).

On the other hand, call type 5 is added to the cell selection request message.
If 01 is not included, the cell type forming the lowermost layer area is determined as the connection destination of the destination PS based on the location information of the destination PS, that is, the area number of the hierarchical format held according to the hierarchical structure of the cell. (808). For example, when the large cell calling area number and the medium cell calling area number are registered as the position information, the medium cell is selected as the connection destination. Then, a cell selection response message including the cell type selected by the processing of 808 is generated and transmitted to the MSC (80
6) The process ends (807).

FIG. 9 shows a processing flowchart of cell selection confirmation (900) in the cell selection device. Upon receiving the cell selection confirmation request message from the MSC 370, the cell selection device 360 confirms the cell selection process (90).
1). The cell selection confirmation message includes information on the terminal moving speed 508 of the destination PS transmitted via the destination PS-the destination BS-the destination BSC.

In the cell selection process confirmation, first, the call type 501 stored in the memory is called during the destination cell selection process performed prior to this process (902). Also, the receiving side P
The terminal moving speed 508 transmitted from S is set to (130
9) Store in memory. Next, the above-mentioned information such as the call type stored in the memory is assigned to the cell selection table 133, and the best cell type to be connected by the destination PS is selected (90
4) Yes. Next, the best cell type selected in this step 534 and the destination PS at this time are connected B
It is determined whether or not the cell type of S matches (131
8). If it is determined that they do not match, the process proceeds to the switching instruction process to the best cell / BS for the originating PS (90
7) Generate a cell switching required message, send it to the MSC (908), and end the process (909). On the other hand, destination PS
When it is determined that the cell type of the BS to which the B is connected and the best cell type selected in the processing of 904 are the same, the destination PS
It is assumed that the cell switching is instructed to (90
6). Here, in the processing of 906, the meaning of "no cell switching" is to "maintain the cell type", and in order to achieve the same purpose, no switching instruction may be issued. After that, a cell switching unnecessary message, which is a kind of cell selection response message, is generated and transmitted to the MSC (908), and the process is terminated (909).

FIG. 10 shows an operation flowchart of the originating cell selection processing program 401 of the terminal with cell selection function. The cell selection function-equipped PS 100 that is being activated by the PS integrated control program 120 has a CPU 102 when a call request is input from the user via the MMI unit 104.
The calling-side cell selection processing is executed by executing the calling-side cell selection processing program 401 at.

In the originating cell selection processing 401, first, PS
The call type 501 of the call originated from 100 is identified (1001) and the same information is stored in the memory 103. Regarding the input of the call type, the user inputs it through the call type selection button 204 or the like, or is automatically set by the CPU. When the call type is “data” 504, the expected line time 505 (“long time” /
If the "short time" or time value) is also known in advance, the expected line time is also stored in the memory 103. Also, the terminal moving speed 508 obtained by the moving speed detection processing
(“Low speed” / “high speed” or moving speed value) is identified (1002) and the same information is stored in the memory 103. Next, the above information stored in the memory 103 is assigned to the cell selection table 133 on the cell selection table 133, and the best cell type to be connected by the originating PS is selected (1003) and the processing is terminated (100
4).

FIG. 11 shows an operational flowchart of the called-side cell selection processing program 402 when the terminal with cell selection function receives a call. The PS 100 with cell selection function, which is integrally controlled by the PS integrated control program 120, is
When an incoming call from S is made, the CPU 102 executes the destination cell selection processing program 402 to perform the destination cell selection processing.

In the destination cell selection processing 402, first, from the originating side PS, the originating side BS-the originating side BSC-the originating side MSC-the destination side MS.
The PS 100 receives the call setup message transferred via the C-destination BSC-destination BS and identifies whether the message includes information on the call type of the incoming call (1101).

As a result of the conditional branching processing of 1101, if the call setup message includes the call category, the call category 5
71 is identified (1102) and the same information is stored in the memory 103. If the call type is “data” 504 and the expected line time 505 is also transmitted from the calling PS, the expected line time is also stored in the memory 103. In addition, the destination PS moving speed 508 obtained by the moving speed detection process during successive activation is identified (110
3) The same information is stored in the memory 103. By allocating each of the above information stored in the memory 103 to the cell selection table 133, the best cell type to be connected by the destination PS is selected (1104). Next, it is identified (1105) whether or not the cell type of the BS to which the destination PS is currently connected matches the selected best cell type. If they do not match, it is necessary to switch to the best cell and cell switching (BS switching) is instructed (1106). Then, the information of the cell type of the switching destination and the information of the switching instruction are passed to the cell system control program (processing) being activated on the CPU 102, and the processing is ended (1109). On the other hand, if the cell type of the BS to which the terminating side PS is connected matches the best cell type selected by the processing of 1104, the cell system control program currently running on the CPU 102 is instructed not to switch cells. The process is passed to (process) and the process is terminated (110).
9).

By the way, as a result of the conditional branch processing of 1101,
If the call type is not included, it is determined whether or not the destination PS movement speed obtained by the movement speed detection processing of the PS that is being sequentially activated and the cell type of the BS currently connected to the destination PS are matched. Is performed (1107). This judgment is, for example,
The PS movement speed is associated with the cell type in advance, such as "small cell" when the PS movement speed is in the low speed area, "medium cell" when it is in the middle speed area and "large cell" when it is in the high speed area. Speed-Performed by holding the cell table in a memory or the like.
For example, when the PS speed is actually low, it is determined whether or not the cell type of the BS being connected is a small cell. If the cell types do not match, cell switching is instructed to match the cell types. The cell type of the switching destination is the cell type selected from the speed-cell table. Then, the information of the cell type of the switching destination and the information of the switching instruction are currently stored in the CPU
The process is passed to the cell system control program (process) that is being activated, and the process is terminated (1109). On the other hand, if the cell types are matched, an instruction to make cell switching unnecessary is currently issued.
The process is passed to the cell system control program (process) running on the PU 102, and the process is terminated (1109).

FIG. 12 shows a cell selection device 360 or
The operation | movement flowchart of the BUSY correspondence cell switching process program 132 performed by PS100 with a cell selection function is shown.

The BUSY-compatible cell selection switching processing program 550 is activated in the following cases.

(1) The optimum connection destination BS12 determined by the cell selection process on the originating side by the PS100 with cell selection function
0, 130, 140 or when a request is made to a communication satellite to establish a wireless line for making a call, the PS of the same BS
-When it is notified that the BS line is not available (radio line BUSY notification).

(2) Destination MSC is the destination PS-the destination BS.
-Any line between the destination BSC and the destination MSC is BUS
When Y is notified and the cell selection device 360 is requested to handle the line BUSY.

In the above cases (1) and (2), the line BUSY
The cell type of BS or BSC / MSC is passed as information to the BUSY compatible cell switching process. For example, PS-
If the line is BUSY between BSs for medium cells, "medium cell" is passed as the cell type. In other words, the CPU that failed to make the call
When the control unit determines, for example, the failed cell type is stored in the memory (1201).

Next, the user sets the priority setting buttons 208, 2
Priority communication index “quality priority” entered by pressing 09
Identify communications or "charge-priority" communications (120
2).

When "charge priority" communication is selected in 1202, it is discriminated whether or not the line BUSY cell type stored in the memory 103 is the minimum cell type of the hierarchical cell type (1203). For example, when the line BUSY cell type is "small cell", it is the minimum cell type. As a result of the processing of 1203, in the case of the minimum cell type, a cell type that is one size larger is selected (1204) and this processing is ended (1209). 12
As a result of the processing of 03, when the cell type is not the minimum cell type, the cell type which is one size smaller is selected (1206) and this processing is ended (1209).

On the other hand, when the “quality priority” communication is selected in 1202, the line B stored in the memory 103 is selected.
It is identified whether the USY cell type is the maximum cell type of the hierarchical cell type (1205). As a result of the processing of 1205, when the maximum cell type is selected, the cell type that is one size smaller is selected (1
206) This process ends (1209). When the result of the processing 1205 is not the maximum cell type, a cell type one size larger is selected (1204) and this processing is ended (1209).

PS100 or MSC350 has 12
The cell type selected in 04 or 1206 becomes the output of this processing, and the connection request to the BS of the same cell type is made again.

FIG. 13 shows a call connection sequence including a cell selection procedure for making a call from the PS 100.

The PS 100 establishes a radio link establishment process 1301 with the small cell BS 320, and PS to BS 320-BS.
Call setup message (1303, 130
4) to MSC350. In this message, in addition to general connection information required for call setup, a call type 501 and a terminal moving speed 508 used during cell selection processing.
Etc. is added. Upon receiving the call setup message 1304, the MSC 350 informs the cell selection device 360 of
A cell selection request message 1305 including information such as the call type 501 and the terminal moving speed 508 is transmitted. The cell selection device 360 starts the originating cell selection process 510, and after the process is completed, sends a cell selection response message 1306 to the MSC 350.
Return to As information of the message, when cell switching is not required, that is, cell selection OK (1351)
Then, the call setup acceptance message 130 is sent to the PS 100.
9, 1311 and 1312 are transmitted, an initial address message (hereinafter referred to as an IAM message) 1310 is transmitted to the network side (incoming side), and the line connection processing 13
After performing 16, the communication is started (1317). on the other hand,
When cell switching is requested, that is, cell switching NG (135
In the case of 2), the release completion message (1318) including the cell type of the switching destination as information in addition to the general information element is set as P.
Send to S100. The PS 100 sends a call setup message 1322, 132 to the BS 330 of the cell type designated as the switching destination after the wireless link establishment process (1321).
3,1324 is transferred to MSC350. MSC350
To PS100 call setup acceptance message 1326, 132
7, 1328 is returned, and the IAM message 1310 is transmitted to the called side MSC which is the called side network 1390 or the gateway exchange. Finally line connection processing 1316, 133
After performing 1, 1330, 1329, communication is started (1332).

FIG. 14 shows a call connection sequence when a call is made from the PS 100, which is a mobile terminal with a cell selection function.

The control unit of PS100 performs the originating cell selection process 1
410 is started, and the cell type of the connection destination is determined. Then P
In S100, a wireless link establishment process 1301 is performed with the BS 320 that is determined as the connection destination. PS100 to BS
320, call setup message 130 via BSC 322
2, 1303, 1304 are transmitted to the MSC 350. M
SC350 sends a call setup acceptance message 130 to PS100
IAM message 1 that returns 9, 1311 and 1312
310 is transmitted to the called MSC which is the destination network 1390 or the gateway exchange. Line connection processing 1316, 13
When 15,1314,1313 are performed and the circuit is opened, communication is started (1317).

FIG. 15 shows a call connection sequence including a cell selection procedure at the time of an incoming call to the PS 100.

M that has received the IAM message 1310 from the originating network 1590 (the originating MSC or the gateway exchange)
The SC 350 transmits the position information request message 1501 to the position information DB 370. Location information DB370
Then, the area number that is the location information of the destination PS is searched,
The location information response message 1502 including the same information is sent to the MS
Reply to C350. Next, to the cell selection device 360, the receiving side P
A cell selection request message 1503 is transmitted to request the determination of the connection destination cell of S. This message includes the call type 501 transmitted from the originating network 1590 (may not be transmitted) and the area number 620 as position information of the destination PS. Upon receiving this message, the cell selection device 360 activates the destination cell selection processing 1520, determines the cell type of the BS that is the calling source of the destination PS, and the cell selection response message 1504 is transmitted to the MSC 350. MS
C350 is a BSC322-BS320 corresponding to the connection destination cell type based on the connection destination cell type information and the position information.
Call setup messages 1505, 150 to the destination PS via the
6,1507 is transmitted. The destination PS returns the call setup acceptance message 1510, 1511, 1512 to the MSC 350. This message includes the moving speed information of the destination PS in addition to the general call setup message. Upon receiving this message, the MSC 350 has the cell selection device 3
The cell selection confirmation request message 1513 including the moving speed information of the destination PS is transmitted to the terminal 60. Cell selection device 3
In 60, the cell selection processing confirmation 1530 is activated, it is determined whether or not the cell type determined in the destination cell selection processing 520 is valid, and the result is a cell selection confirmation response message 1514.
And send to MSC350. Destination cell selection process 1
If the cell type selected in 520 is valid (135
1) is line connection processing 1316, 1515, 1516,
After performing 1517, communication is started (1317).
On the other hand, if the cell type is invalid (1352), the call setup messages 1518, 1519, 1518, 1519, through the BSC332, BS330 of the new connection destination cell type (the middle cell in the figure) determined at the time of confirming the cell selection process. PS 1520
Send to 0. PS100 is the call setup acceptance message 15
23, 1524, 1525 are returned to MSC350.
After that, line connection processing 1526, 1527, 1528, 1
316 is performed, the communication line is opened, and communication is started (13
32). Also, the old line (MSC350-BSC322-
BS320) line disconnection processing 1529, 153
0,1531 is performed.

FIG. 16 shows a call connection sequence when an incoming call is made to PS100 which is a mobile terminal with a cell selection function.

The MSC 350 which has received the IAM message 1310 from the originating MSC existing in the originating network 1590 or the gateway exchange sends a location information request message 1501 to the location information DB 370. Location information DB
In 370, the area number, which is the location information of the destination PS 100, is searched, and the location information response message 1 including the same information is searched.
502 is returned to the MSC 350. The MSC 350 determines the cell type forming the area of the lowest layer area number of the position information as the cell type of the connection destination based on the position information, and the destination side P via the BSC 322 or BS 320 corresponding to the connection destination cell type.
Call setup messages 1505, 1506, 15 to S100
07 is transmitted. This message includes information about the call type 501 transmitted from the calling network (however, it may not be included). The destination PS is the destination cell selection processing 152
0 is started, and the optimum cell type to connect to itself is obtained based on its own moving speed and the call type 501 transmitted from the destination side, and whether or not it matches the cell type of the currently connected BS Determine whether. When the determination results are the same, that is, cell selection is OK
In the case of (1351), call setting acceptance messages 1510, 1511, 1512 are transmitted to the MSC 350. After that, line connection processing 1517, 1516, 1515, 131
6 and the line is opened, communication is started (131
7). On the other hand, when the determination results do not match, that is, when the cell selection is NG (1352), the release completion message 160
1, 1602, 1603 including the information of the new connection destination cell type is transmitted to the MSC 350. The MSC 350 sends the call setup messages 1518, 1519, 1520 to the PS1 via the BSC 332, BS 330 of the new connection destination cell type.
Send to 00. PS100 is the call setup acceptance message 1
523, 1524, 1525 are returned to MSC350. After that, line connection processing 1526, 1527, 152
After performing 8 and 1316, communication is started (1332).

FIG. 17 shows a call connection sequence including a cell selection procedure when handing over from the PS 100.

The PS 100 requesting a handover (hereinafter referred to as H / O) due to quality deterioration of the wireless line between the PS-BS of 1317 during communication transmits a call setting message 1701 including an H / O request to the MSC 350. To do. Subsequent processing and procedures in each device are similar to those at the time of calling. However, from the MSC350 to the PS of the other party
Alternatively, no message is sent to the network 1790 in which the fixed telephone is accommodated. After transmitting the call setting acceptance message 1309, 1311 and 1312, the MSC 350 switches the line from the old connection line to the new connection line (1710).

FIG. 18 shows a call connection sequence when the cell selection function-equipped terminal 100 requests a handover.

PS 100 is PS-B of 1317 during communication.
The calling-side cell selection processing 1810 is activated to request H / O due to quality deterioration of the wireless line between the S and the like. The originating cell selection process 1810 determines the cell type of the H / O destination and transmits a call setup message 1705 including the H / O request to the BS 330 having the same cell type and good line quality. Furthermore, BSC
The message 1706, 1707 is sent to the MS via 332
Send to C350. Subsequent processing and procedures in each device are the same as those at the time of calling. However, there is no message transmission from the MSC 350 to the partner network 1790 (the network of the PS of the communication partner or the fixed telephone). In addition, MSC35
0 is a call setting acceptance message 1326, 1327, 132
After 8 transmissions, the line is switched from the old connection line to the new connection line (1710).

FIG. 19 shows a sequence when the PS 100 performs position registration.

A case will be described in which the calling area within the service area is changed due to the movement of the PS 100 itself. The PS 100 activates the location registration destination cell determination processing 1910, and searches a connectable BS from the lower layer cell by detecting the carrier emitted by the BS. The PS 100 transmits the location registration message 718 to the connectable BS 330 detected by this processing after the wireless link establishment processing 1321. BS330 connects to MSC350 via BSC332
The location registration messages 1901 and 1902 are transmitted to.
This message includes the terminal number of the PS requesting location registration and the area number of the calling area to which BS 330 belongs. The MSC 350 also transmits a location registration message 1904 to the location information DB 370 in the same manner. After receiving this message, the position information DB 370 activates the position registration processing 1920 and writes the area number, which is the position information of the PS 100, in the position information table. After the processing is completed, the location information DB 370 stores the location registration acceptance message 19
05 to the MSC 350. Next, the MSC 350 sends the same message 1906, 1907, to the PS100.
1908 is transmitted to notify that location registration has been performed.
Note that the location registration acceptance message can also disconnect / release the line by using the release completion message.
Note that the PS 100 with cell selection device also performs location registration in the same sequence.

FIG. 20 shows a call connection sequence at the time of the calling side radio line BUSY. Specifically, this is a sequence for switching the PS-BS wireless line to BUS of another cell type for communication when the PS 100, which is a wireless terminal with cell selection function, makes a call.

The PS 100 uses the originating cell selection process 1810.
To determine the cell type or BS of the connection destination. A wireless link establishment process is performed with the BS 320 determined as the connection destination, but a line BUSY notification indicating that there is no idle line is received from the BS 320 (701b). Then BUS
The Y-corresponding cell switching process 2010 is activated, and B of another cell type is activated.
S is newly determined. BS3 determined by this process
After the wireless link establishment process 1321 is performed for 30, the calling process is performed via each device to start line connection and communication.

FIG. 21 shows a call connection sequence when the called side wireless line BUSY. Specifically, from MSC350 to P
When the incoming call to S100 is made, the wireless line between the PS-BS on the receiving side is BUSY, so the line is switched to the BS of another cell type to perform the incoming call and connection to the PS on the receiving side.

Similar to the incoming call sequence shown in FIG. 15, the BS
The call setup messages 1505 and 1506 are transmitted to 320. Since BS320-PS100 does not have an empty line, BS320 sends M release completion messages 2101 and 2102 containing information that there is no empty line (line BUSY).
Send to SC350. MSC that received this message
350 transmits a BUSY correspondence request message 2103 to the cell selection device 360. Cell selection device 360
Starts the BUSY-compliant cell switching process 2010, newly determines another cell type, and sends a BUSY-compliant response message 2
MSC350 including information of the cell type determined in 104
Send to MSC350 is BS3 of the decided cell type
30 through BSC 332, call setup message 151
8, 1519 is transmitted. After that, communication is started. Also,
The BUSY compatible cell switching process 2010 is similarly activated even after the cell selection process confirmation 1560 and there is no available wireless line.

[0066]

According to the present invention, in a mobile communication system of a multi-layer cell system, a terminal for making a call connection is connected to a switching center with information on a call type, a moving speed of the terminal, and a predicted line use time. It transmits to the cell selection device, and in the cell selection table of the cell selection device, based on the same information, selects the cell type most suitable for the terminal to make a line connection, and notifies the terminal of the same cell type. , By connecting the line with the wireless base station of the same cell type, it is possible to secure the communication quality suitable for each call and prevent the traffic from concentrating on the wireless base station of a specific cell type. And again,
After the cell selection process, if there is no vacancy in the wireless link between the wireless base station of the same cell type and the terminal, or if there is a need for channel switching during communication, another If there is no available line, select another cell type and switch the channel to the line of the wireless base station of the same cell type to prevent communication, or drastic deterioration of communication quality due to deterioration of radio wave condition, forced It is possible to reduce the occurrence rate of line disconnection.

[Brief description of drawings]

FIG. 1 is a diagram showing an internal configuration of a mobile radio terminal according to the present invention.

FIG. 2 is a diagram showing an external configuration of a mobile radio terminal according to the present invention.

FIG. 3 is a diagram showing a configuration of a mobile communication system according to the present invention.

FIG. 4 is a diagram showing a configuration of a cell selection program according to the present invention.

FIG. 5 is a diagram showing a cell selection table relating to the present invention.

FIG. 6 is a flowchart showing a call originating from a mobile radio terminal according to the present invention.

FIG. 7 is a flowchart showing a cell selection process on the calling side according to the present invention.

FIG. 8 is a flowchart showing a called-side cell selection process related to the present invention.

FIG. 9 is a flowchart showing cell selection confirmation processing according to the present invention.

FIG. 10 is a flowchart showing a cell selection process on the calling side according to the present invention.

FIG. 11 is a flowchart showing a called-side cell selection process according to the present invention.

FIG. 12 is a flowchart showing a cell selection process at BUSY according to the present invention.

FIG. 13 is a communication line setting sequence diagram of the present invention.

FIG. 14 is a communication line setting sequence diagram of the present invention.

FIG. 15 is a communication line setting sequence diagram of the present invention.

FIG. 16 is a communication line setting sequence diagram of the present invention.

FIG. 17 is a communication line setting sequence diagram of the present invention.

FIG. 18 is a communication line setting sequence diagram of the present invention.

FIG. 19 is a communication line setting sequence diagram of the present invention.

FIG. 20 is a communication line setting sequence diagram of the present invention.

FIG. 21 is a communication line setting sequence diagram of the present invention.

[Explanation of symbols]

100 ... Wireless terminal, 101 ... Antenna, 102 ... Control unit, 103 ... Storage device, 104 ... Man-machine interface unit, 105 ... Interface unit with external information processing device, 110 ... RF unit, 111 ... Common RF unit, 112 …
Large cell RF section, 113 ... Medium cell RF section, 114 ... Small cell RF section, 115 ... GPS RF section, 116 ... Wireless line control section, 120 ... Wireless terminal integrated control program, 1
21 ... Large cell control program, 122 ... Medium cell control program, 123 ... Small cell control program, 130
... cell selection processing unit, 131 ... terminal side cell selection program, 132 ... BUSY cell switching program, 133 ...
Cell selection table, 134 ... Moving speed detection program,
135 ... GPS control program.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Masato Hayashi Inventor Masato Hayashi 1099, Ozenji, Aso-ku, Kawasaki-shi, Kanagawa Ltd. System Development Laboratory, Hitachi, Ltd.

Claims (15)

[Claims] 1. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells includes a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, characterized in that data to be selected is stored in a call setting data format. 2. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the medium cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, characterized in that data serving as a reference for selection is stored in a handover setting data format. 3. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, characterized in that call type information indicating a call content of the mobile radio terminal as a reference for selection is stored in a call setting data format. 4. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, characterized in that call type information indicating a content of a call of the mobile radio terminal as a reference for selection is stored in a handover setting data format. 5. The communication line setting method according to claim 3, wherein the call type information is any one of voice, image and data. 6. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, which stores a line use time information, which is used as a reference for selection and is required when the mobile radio terminal communicates arbitrary information, in a call setting data format. 7. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A communication line setting method, which stores a line use time information, which is used as a reference for selection and is required when the mobile radio terminal communicates arbitrary information, in a handover setting data format. 8. The communication line setting method according to claim 6, wherein the line use time information is estimated in advance before communication between the wireless base station and the movable wireless terminal is started. A communication line setting method, which is a line use time or a line use time self-reported by a user. 9. The communication line setting method according to claim 6, wherein the line use time information is estimated in advance before communication between the wireless base station and the movable wireless terminal is started. A communication line setting method characterized in that it is time class information in which the line use time or the line use time self-reported by the user is divided into a plurality of classes. 10. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells includes a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A method for setting a communication line, characterized in that the moving speed information of the mobile radio terminal as a reference for selection is stored in a call setting data format. 11. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells comprises a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. A mobile radio terminal that is hierarchically configured from a small cell composed of a service area smaller than the middle cell, and a mobile radio terminal that can move in each cell is one of the large cell, the medium cell, and the small cell. A method of setting a communication line, characterized in that moving speed information of the mobile radio terminal, which is a reference for selection, is stored in a handover setting data format. 12. The communication line setting method according to claim 10, wherein the moving speed information is a moving speed that accompanies movement of the movable wireless terminal. 13. The communication line setting method according to any one of claims 10 to 11, wherein the moving speed information is speed class information in which a moving speed associated with the movement of the movable wireless terminal is divided into a plurality. Communication line setting method characterized by. 14. A cell selection table used when selecting a cell to be used for communication between a wireless base station installed in a mobile communication service area divided into a plurality of cells and a movable wireless terminal. In the above, as a table parameter of the cell selection table, it is configured hierarchically from a large cell composed of a large service area, a medium cell composed of a service area smaller than the large cell, and a small cell composed of a service area smaller than the medium cell. The cell information of the mobile communication service area to be used and at least one of the call type information, the terminal moving speed information, and the line usage time information are provided, and the calling side wireless terminal should use the combination of the table parameters. A cell selection table characterized by determining cells. 15. A communication line setting method in mobile communication, wherein a mobile communication service area divided into a plurality of cells includes a large cell composed of a large service area and a medium cell composed of a service area smaller than the large cell. The mobile radio terminal is hierarchically configured from a small cell having a smaller service area than the medium cell, and the mobile radio terminal sets up data as a reference for selecting one of the large cell, the medium cell and the small cell. A communication line setting method comprising storing in a data format to generate a communication line setting signal and transmitting the communication line setting signal to a radio base station provided for each cell.