JPH05336026A - Mobile communication system and mobile terminal equipment used for the system - Google Patents

Abstract

PURPOSE:To reduce the control signal traffic required for position registration revision by deciding optimizingly the shape of a position registration zone for a mobile terminal equipment mounted on a mobile body depending on a moving speed, a moving direction at that time and on a kind of the mobile body. CONSTITUTION:The mobile set main body 19 of a mobile terminal equipment is provided with a reception system section 12 receiving and recognizing a coordinate sent from a base station being an opposite party of communication and with a coordinate memory 15' being a means storing the coordinate. An algorithm control section 15 in the mobile terminal equipment sets the position registration zone in the following way depending on plural constants based on a kind of the mobile body on which the mobile terminal equipment is mounted, a moving speed, a moving direction of the mobile terminal equipment. That is, the length up to a succeeding position registration zone is set longer in the traveling direction of the mobile terminal equipment and shorter in the opposite direction. The moving direction is identified based on the coordinate transition of the base station having a higher reception sensitivity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for mobile radio communication for communicating with mobile phones, mobile phones and other base stations. In particular, the present invention relates to a technology for reducing control signal traffic required for location registration at the time of switching and configuration of a location registration zone of a mobile terminal in mobile radio communication.

[0002]

2. Description of the Related Art In mobile communication, there are a mobile terminal device, a base station wirelessly connected to the mobile terminal device, and a control station wiredly connected to the base station. The current position of the moving mobile terminal device is registered in the base station and the control station, and when a call is made to the mobile terminal device, a radio wave is transmitted from the registered base station to the mobile terminal device. .. A section in which the mobile terminal device registers its own current position is called a position registration zone. Here, the location registration zone refers to a set of radio wave propagation areas possessed by a plurality of base stations.

A conventional example will be described with reference to FIG. FIG. 6 is a block diagram of a conventional mobile telephone device. The control unit 15
In addition to performing control in ordinary telephone communication performed by a fixed terminal device, it receives a control signal from a base station and identifies the base station with the highest reception level as the closest base station, and belongs to that base station. The zone is searched to determine whether or not the zone belongs to the zone in which the current location is registered. If the base station does not belong to the zone in which the location is currently registered, the location registration is updated.

[0004]

In such a method, if the location registration zone is predetermined and fixed, the mobile terminal device near the boundary of the location registration zone repeats only a few movements. However, a large number of location registration updates are repeated, resulting in an increase in control signal traffic required for location registration.

In order to avoid this problem, there is also known a method in which once location registration is performed, a plurality of peripheral base stations around the base station are collectively used as the location registration zone of the mobile terminal device. If this method is used, the location registration update is not frequently performed because the location registration zone is moved across the boundary. However, this method is good when the distance traveled is short, but for a mobile terminal device that continues to move, to perform the next location registration update, the location registration is performed again by moving a distance equal to the radius of the location registration zone. You have to update.

Of course, in the case of the fixed zone method described above, the same point is required to update the location registration every time the user moves to the next zone, but a plurality of base stations are collectively formed into a new zone. In this method, the belonging of the mobile terminal device must be notified to a plurality of base stations that compose the zone, and the procedure is complicated and the control signal traffic required for it is naturally large. The decline is inevitable.

The present invention has been made against such a background, and is a system in which a plurality of base stations are registered in advance in a mobile terminal device, and a mobile terminal capable of reducing control signal traffic required for location registration update. The purpose is to provide a device. The present invention aims at effective use of radio waves.

[0008]

The first aspect of the present invention is to:
In the mobile terminal device, which is a mobile terminal device and includes means for receiving and recognizing coordinates transmitted from a base station which is a communication partner, and a means for storing the coordinates, a new base station registered in the storing means. For, the length to the next location registration zone should be longer in the direction of travel of the mobile terminal device from the multiple constants determined by the type of mobile unit equipped with the mobile terminal device and the direction and speed of movement of the mobile terminal device. It is characterized in that a means for setting the position registration zone so as to be shortened in the opposite direction is provided.

It is preferable that the moving direction includes means for identifying the moving direction based on coordinate transition of a base station having high reception sensitivity.

It is desirable that the moving speed is measured by a fading pitch of a radio wave coming from the base station.

A second aspect of the present invention is a mobile communication system using this mobile terminal device, comprising a plurality of base stations and a mobile terminal device communicating with the base station, wherein the base station comprises: In a mobile communication system including means for transmitting coordinates to the mobile terminal device, the mobile terminal device of the present invention is provided as the mobile terminal device.

[0012]

The optimum location registration zone is set based on the moving direction and speed of the mobile terminal device itself. That is, the location registration zone is configured such that the next location registration zone becomes longer in the traveling direction of the mobile terminal device and becomes shorter in the opposite direction. As a result, even if the area of the location registration zone is constant, it is possible to reduce the traffic for control signals for changing the setting of location registration.

Further, by setting the constants in the zone calculation calculation according to the moving speed, moving direction, and type of the moving body on which the device of the present invention is mounted, the position registration zone setting with a small possibility of being reset individually is set. You can

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The configuration of the first embodiment of the present invention will be described with reference to FIG. FIG. 1 is a block diagram of a first embodiment device of the present invention.

The present invention is a receiving system unit 12 which is means for receiving and recognizing coordinates transmitted from a base station which is a communication partner.
And a coordinate memory 15 'which is a means for storing these coordinates.
In the mobile terminal device provided with, for the new base station registered in the coordinate memory 15 ', from a plurality of constants determined from the type of mobile body in which the mobile terminal device is mounted and the moving direction and speed of the mobile terminal device. The control unit 15 is equipped with an algorithm that is a means for setting the position registration zone so that the length to the next position registration zone is long in the traveling direction of the mobile terminal device and short in the opposite direction. .. This moving direction is identified based on the coordinate transition of the base station with high reception sensitivity.

Next, a first embodiment of the present invention will be described with reference to FIG. FIG. 2 is a diagram showing a location registration zone. At the center of each zone, there are base stations Z _{1 to} Z _{i + 1} , and these base stations Z _{1 to} Z _{i + 1} transmit their position information coordinates as radio signals by radio waves. This is the base station Z ₁ -Z
_This is done by transmitting the coordinate information of the base stations Z _{1 to} Z _{i + 1} following the _{i + 1} identification code. This coordinate information is X
Information of several digits for each of Y and Y is sufficient, and the radio wave transmission time does not become long at all.

[0017] It is also possible to set in advance in the memory of the mobile terminal apparatus in correspondence with the base station Z ₁ ~Z i + ₁ of coordinate information identifying information of the base station Z ₁ ~Z i + _1.

In the first embodiment of the present invention, the base stations Z _{1 to} Z _{i + 1.}
Can be represented by two-dimensional coordinates of X and Y because they are arranged in a plane.
The coordinates of the base station Z ₁ are (X ₁ , Y ₁ ), the coordinates of the base station Z ₂ are (X ₂ , Y ₂ ), ..., The coordinates of the base station Z _{i + 1} are (X _{i + 1} , Y _{i +). 1} ).

When the mobile terminal device 1 is in the zone of the base station Z _i , the location registration zone 1'of the mobile terminal device 1 includes the base stations Z ₁ , Z ₂ , Z ₃ , Z _i-1 , Z _i . It consists of 10 zones. When the mobile terminal device 1 is in the zone of the base station Z _i is the coordinate which is transmitted from the base station Z _i (X _i,
Y _i ) is received and stored. When the mobile terminal 1 comes to move from the zone of the base station Z _i to the base station Z _{i + 1} zone, the mobile terminal apparatus 1 is transmitted from the base station Z _{i + 1} coordinates (X i _{+ 1,} Y _{i + 1} ) is received. Mobile terminal device 1
Determines whether the position of the coordinates (X _{i + 1} , Y _{i + 1} ) is outside the position registration zone 1 ′ and the position registration update is required. As shown in FIG. 2, since the position of the coordinates (X _{i + 1} , Y _{i + 1} ) is outside the position registration zone 1 ', the position registration is updated. From the mobile terminal device 1, the number of the mobile terminal device 1 and the coordinates (X _i , Y _i ) of the base station Z _i are used as a position registration signal.
To the base station Z _{i + 1} .

The base station Z _{i + 1} has the number of the mobile terminal _{1 and} the coordinates (X _i , Y _i ) and (X _{i +} ) of the base stations Z _i and Z _{i + 1} with respect to a control station (not shown). ₁ , Y _{i + 1} )
A position registration number including the above is transmitted, and a position registration confirmation signal is transmitted to the mobile terminal device 1.

Next, how the mobile terminal device 1 moves from the base station Z _i to the base station Z _{i + 1} and determines the position registration zone 2'when the position registration is updated will be described with reference to FIG.
Will be described. FIG. 3 is a diagram for explaining an algorithm for setting the location registration zone 2 '. When the mobile terminal device 1 moves from the base station Z _i to the base station Z _{i + 1} , the position registration update is performed if the base station Z _{i + 1} is outside the existing position registration zone 1 '. The new zone is the range surrounded by the straight lines L1, L2, L3, and L4 in FIG. The straight lines L1, L2, L3 and L4 are obtained as follows.

Since the straight line L0 passes through the coordinates (X _i , Y _i ) and the coordinates (X _{i + 1} , Y _{i + 1} ), Y = [(Y _{i + 1} −Y _i ) / (X _{i + 1)} -X _i)] represented by _{X + (X i + 1 ·} Y i -X i · Y i + 1) / (X i + 1 -X i). Next, the straight line L1 is obtained. Since the straight line L1 is a straight line whose distance from the straight line L0 is M1, Y = L0 + Z = [(Y _{i + 1} −Y _i ) / (X _{i + 1} −X _i )] _{X + (X i + 1 ·} Y i -X i · Y i + 1) / (X i + 1 -X i) + Z _{where, Z = M1 (X i +} 1 -X i) / W + M1 (Y i + ₁ -Y _i) ² / _{[W (X i + 1 -X i} ) ] W = _{[(X i + 1 -X i)} 2 + (Y i + 1 -Y i) 2 ] ^1/2. Similarly, L2 is a straight line obtained by translating the straight line L0 by -M2 in the perpendicular direction. L3 is a straight line that is parallel to the line L0 and passes through the coordinates (X _{i + 1} , Y _{i + 1} ) by -M3 in the orthogonal direction, and L4 is a straight line that is translated by M4 in the orthogonal direction. .. These straight lines L2, L3,
Any of L4 can be easily coordinated (X _i ,
Y _i ), (X _{i + 1} , Y _{i + 1} ) and the parallel translated distances M2, M3, M4, respectively.

Each time the mobile terminal device 1 performs a mobile registration update, a new location registration zone 2'is created by this algorithm.
And when entering the zone of the next base station Z _{i + 1} , receive the coordinates (X _{i + 1} , Y _{i + 1} ) from that base station Z _{i + 1} ,
It is determined whether or not it is within the area surrounded by the calculated straight line, and if it is within the area, position registration update is not performed, and only the coordinates (X _{i + 1} , Y _{i + 1} ) of the base station Z _{i + 1} Memorize If the coordinates (X _{i + 1} , Y _{i + 1} ) are outside the area, the position registration is updated. The same algorithm is calculated in the control station and is used as a paging area for incoming calls to the mobile terminal device 1.

Next, how to determine the constants M1, M2, M3 and M4 will be described. These constants set the size of the location registration zone 2'and therefore usually depend on the system design of the mobile communication system. For example, if M1 = M2 = M3 = M4, it is close to a normal circular zone. Location registration zone 1 ', 2' since the incoming call paging zone to the mobile terminal device 1, the number of the base station Z ₁ to Z i + ₁ contained therein, controls who is small is easy .. On the other hand, the control signal traffic required for location registration is smaller in the location registration zones 1'and 2 '. Therefore, it is desirable to use a system in which the location registration zones 1'and 2'have the same size and require less control signal traffic for location registration.
An object of the present invention is to set (M1 + M2) × (M3 + M4) constant, that is, even if the size of the position registration zones 1 ′, 2 ′ is the same, (M1 + M2) <(M3 + M4) or M3 <M4 The purpose is to reduce the traffic for control signals required for registration. That is, for a mobile terminal device 1 having a linear movement distance that is larger than the diameters of the position registration zones 1 ', 2', even if M1 + M2 is made small, the mobile terminal device 1 moves in the direction perpendicular to the traveling direction. Since it is considered that the number of traffic signals is small, the traffic for control signals required for location registration does not increase. Further, since it is considered that the probability of moving in the opposite direction to the traveling direction is low, setting M3 <M4 makes it possible to reduce the control signal traffic required for location registration. The simplest of these constants M
The method of determining 1, M2, M3, and M4 is to determine in advance according to the type of mobile body on which the mobile terminal device 1 is mounted. That is, since it moves at high speed when mounted on a car, A: M1 = M2 = 1 km, M3 =
1Km, M4 = 4Km, since it rarely moves back when mounted on a train, B: M1 = M2 = 0.5Km, M
3 = 0.2 Km, M4 = 9.8 Km, C: M1 = M2 = 1.5 when mounted on a slow-moving moving body such as a bicycle.
Km, M3 = 1Km, M4 = 2.3Km, etc. may be decided.

However, more precisely these constants M
To determine 1, M2, M3, M4, the mobile terminal device 1
Moving speed information is required. That is, when the movement is fast, the constants M1, M2, M3, M close to the above A and B are set.
4 is set, and when the movement is slow, the value is close to the above C, so that the constants M1, M2, M3, and M4 can be finely determined. The moving speed can be easily detected on the side of the mobile terminal device 1 as shown in FIG. 1 in the case where a speedometer such as an automobile or a train is provided. When the moving speed is measured by the mobile terminal device 1, the speed or constants M1, M2, M3 and M4 obtained from the speed are sent to the control station when the position registration is performed. As a method of determining the constants M1, M2, M3 and M4 from the speed, there are a method of multiplying the speed by a constant count and a method of using a predetermined value in the case of a certain range of speeds. In one embodiment, a method is used in which the speed is multiplied by a constant count to obtain.

Next, the location registration control procedure will be described with reference to FIG. FIG. 4 is a flowchart showing the location registration control procedure. The radio wave of the base station Z _i is received (S1). If deterioration is found in the radio waves of this base station Z _i, a new base station Z _{i
The i + 1} radio wave is received (S2 → S3). The coordinates (X _{i + 1} , Y _{i + 1} ) of this new base station Z _{i + 1} are received and stored (S4). Whether or not this new base station Z _{i + 1} is within the area of the current location registration zone 1'is determined based on the location registration zone calculation formula (S5), and if it is outside the area, the location registration update procedure is executed.

The moving speed of the moving body equipped with the mobile terminal device 1 is detected (S6). A position registration signal including the number of the mobile terminal device 1, the coordinates (X _i , Y _i ) of the old base station, and the moving speed is transmitted (S7). A confirmation of acceptance of the position registration signal is received from the base station Z _{i + 1} (S8). A calculation formula for the position registration zone 2'is created (S9).

Next, FIG. 5 shows a second embodiment of the present invention. FIG. 5 is a block diagram of the apparatus of the second embodiment of the present invention. When measuring the speed of a mobile body not equipped with the speedometer 21, such as a mobile phone carried by a pedestrian, the base stations Z _{1 to} Z _{i + 1.}
It can be measured by measuring the fading pitch of the radio wave received from.

The advantage of the second embodiment of the present invention is that, as shown in FIG. 5, the speed detecting section 22 based on the fading pitch of the radio waves received from the base stations Z _{1 to} Z _{i + 1} is provided in the receiving system section 12. This is the point where The speed detection unit 22 can set the optimum position registration zone 2'for the mobile phone depending on the moving speed. In particular, in the case of a mobile phone, the moving speed is significantly different between when the wearer is walking and when riding in a car. The moving speed is detected, and when the moving speed is fast, the constants M1, M2, M3, and M4 of A and B described above are applied, and when the moving speed is slow, C is applied.

In the above description, an area surrounded by a straight line is considered as an algorithm for obtaining the position registration zone 2 '.
However, the location registration zone 2'is not limited to the area surrounded by the straight line. Another example is an ellipse. In the case of an ellipse, the constants that determine the size of the position registration zone 2'are the major axis and minor axis of the ellipse, and the base station Z ₁ from one focus.
The deviation is ~ Z _{i + 1} . In the mobile terminal device 1 mounted on a high-speed moving body, if the major axis is made longer and the minor axis is made shorter and the coordinates of the registered base stations Z _{1 to} Z _{i + 1} are brought close to the zone boundary, the position registration is performed. A configuration for reducing the traffic for control signals required for is realized. Further, in the first embodiment of the present invention, the straight line L0 passing through the base station Z _{i + 1} in the location registration zone 2 '
Tilted position registration base station Z _{i + 1} of coordinate Been of _{(X i + 1, Y i} + 1) and, the previous base station Z _i coordinates (X
_i , Y _i ), but when the radio wave propagation radii of the base stations Z _{1 to} Z _{i + 1} are small, the coordinates (X _i ,
In some cases, the coordinates before a plurality of stations are more appropriate than Y _i ). Further, in order to detect the average moving direction, a plurality of base stations Z
It is also possible to take the average of the coordinates _{1 to} Z _{i + 1} .

[0031]

As described above, according to the present invention, since the optimum location registration zone is constructed from the moving direction and speed of the own mobile terminal device, the control signal traffic required for location registration update can be reduced. .. Therefore, effective use of radio waves can be achieved.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a location registration zone.

FIG. 3 is a diagram illustrating setting of a location registration zone.

FIG. 4 is a flowchart showing a location registration control procedure.

FIG. 5 is a configuration diagram of a second embodiment device of the present invention.

FIG. 6 is a configuration diagram of a conventional device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Mobile terminal device 1 ', 2'position registration zone 10 Antenna 11 Transmission / reception duplexer 12 Reception system part 13 Transmission system part 14 Frequency synthesizer 15 Control part 15' Coordinate memory 16 Handset 17 Input switch / display 18 Transmitter 19 Mobile unit main body 20 Telephone 21 Speedometer 22 Speed detector Z _{1 to} Z _{i + 1} base station

Claims (4)

[Claims] 1. A mobile terminal device comprising means for receiving and recognizing coordinates transmitted from a base station as a communication partner, and means for storing the coordinates, wherein a new base station registered in the means for storing. Is a long constant in the traveling direction of the mobile terminal device, based on a plurality of constants determined by the type of moving body equipped with the mobile terminal device and the moving direction and speed of the mobile terminal device. A mobile terminal device comprising means for setting a location registration zone so as to be shortened in a direction. 2. The mobile terminal device according to claim 1, further comprising means for identifying the moving direction based on a coordinate transition of a base station having high reception sensitivity. 3. The mobile terminal device according to claim 1, wherein the moving speed is measured by a fading pitch of a radio wave coming from the base station. 4. A mobile communication system, comprising: a plurality of base stations; and a mobile terminal device that communicates with the base station, wherein the base station includes a means for transmitting coordinates to the mobile terminal device. A mobile communication system comprising the device according to claim 1 or 2 as a mobile terminal device.