JPS6090441A - Zone switching system of mobile communication - Google Patents

Abstract

PURPOSE:To eliminate the useless zone switching and to decrease the number of times of zone switching by storing the locus of a mobile device and estimating the future course based on the obtained locus information to switch to an optimum zone. CONSTITUTION:A radio circuit control station MCS contains a memory 5 which stores the locus of a mobile device MSS and a locus information controller 4 which performs writing and reading to the memory 5 and also measures the distances between the MSS and radio base stations MBS(1-3). Thus the distances between the MSS and these base stations MSB are measured several times for a period while the MSS moved from a point A to a point B. When each station MBS sends a distance measurement signal packet (a) to the MSS, the MSS sends a distance measurement answer packet (b) back to each station MBS. Each station MBS obtains a distance l from the answer time and sends it to the station MCS. The controller 4 selects three nearest distances li, lj and lk out of the distance information and stores them in the form of coordinates (li, lj, lk) to the memory 5. When a zone is switched at the point B, the zone is inserted externally from the coordinates of points A and B to estimate a course.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a zone switching system for mobile communications.

[Backbone of invention]

As a conventional zone switching method for mobile communication, for example, in the wireless zone switching method used in car phones,
As shown in Figure 1, the zone switching method is outlined in order to determine the wireless zone to which mobile station M88 will move from the zone it was previously in to another zone. The field level of radio waves from mobile devices was received at each radio base station, and the zone corresponding to the radio base station that received the highest level of radio waves was designated as the new radio zone.

However, in this conventional method, when mobile station MS8 moves from point A to point B in zone 1 as shown in FIG. The drawback was that it was not possible to properly determine whether the signal was coming from the level of the radio waves. In other words, if C7
If 2 is determined, the mobile device will soon move from zone 2 to zone 3, so the zone must be switched again immediately, which puts pressure on the control channel and requires the control processor. There were disadvantages such as putting pressure on the processing capacity of the system.

[Purpose of the invention]

The purpose of the present invention is to eliminate the above-mentioned drawbacks of the prior art, and to provide a mobile communication system that can always switch to the optimal zone based on appropriate judgment, reduce the number of switching operations, and alleviate pressure on control channels and control processor processing capacity. To provide a zone switching method.

[Summary of the invention]

In order to achieve the above object, the present invention stores the locus of movement of a mobile device and estimates the course it is expected to follow based on the locus information, thereby switching to an optimal zone and eliminating unnecessary zone switching. This is a zone switching method for mobile communication that eliminates zone switching and reduces the number of switching times.

[Embodiments of the invention]

An embodiment in which the present invention is applied to a car telephone will be described below with reference to FIGS. 2 to 4.

FIG. 2 is a conceptual diagram showing an overview of a zone switching system for mobile communication according to the present invention. In Fig. 2, in mobile radio communication such as a car phone, a mobile device that communicates while moving communicates with a partner device by communicating with a radio base station, but the communication area of one radio base station ( Since the number of wireless zones (wireless zones) is limited, mobile devices continue communication by switching communication zones one after another as they move. Currently, the mobile station MSS is C7 of wireless base station MBSI.
If you are moving in the direction of the arrow from point A in point A to point C in zone 3 of wireless base station MBS3, at point B you will switch the wireless zone from zone 1, where you were previously located, to the next zone. However, in such cases, in the conventional method, the electric field level in other zones was compared at point B and the zone was switched to the zone of the wireless base station that received the strongest electric field at that time. According to the present invention, the radio network control station MC8 stores the movement trajectory of the mobile device, estimates the future course based on the trajectory information, and switches to the next zone.

FIG. 3 is a side view of the configuration of radio channel control station MC8 in FIG. 2. In FIG. 3, the wireless network control station MC8 has a storage device 5 for storing the trajectory of the mobile device, and the distance from each wireless base station to the mobile device is measured by writing to and reading from the storage device. (distance measurement) trajectory information control device 4
is installed, and the distance to each radio base station is measured several times before the mobile station MSS moves from point A to point B.

FIG. 4 shows an example of a frame format of a packet for distance measurement that the signal control device 3 of FIG. 3 transmits to and receives from each radio base station.

FIG. 4(a) shows a packet sent from each radio base station MBS to the mobile station MSS according to instructions from the signal control device 3.
Following the preamble P and flag F, it is written that the mobile device number, the signal type is a control signal, and the signal content is a ranging signal. FIG. 4(b) shows a ranging response packet sent from the mobile station MSS to the wireless base station MBS, and the mobile station MS8 returns this packet to the wireless base station MB8 within a certain predetermined time limit. There must be. This packet describes the mobile device number, the signal type as a control signal, and the signal content as a ranging response signal. Each radio base station MBS calculates the distance β from its response time and sends it to the radio network control station MC8. Then, the trajectory information control device 4 selects, for example, the three nearest distances from this information, ij, Itk, and calculates the coordinates (Tofij, Itk).
1. ) in the storage area of the storage device 5 corresponding to the mobile station MSS.

For example, in FIG. 2, the nearest wireless base stations MBS1~
The distances 1□, 2□, and β3 from 3 to the mobile station MSS are distances Ri, 1j, and Ak, respectively. If the measurement time points were at points A and B, the corresponding coordinates (11, fi□, 23) would be “IAI '2Al
'3□) and (It1n+ LzB+ 13n)
becomes. Therefore, when switching the zone at point B, the vector from point A to point B is converted to the above two coordinates (j!
□□, 2□□+ 13A) and (β□3, 1□B”3B)
Coordinates of point C (k□..) estimated by estimating the course by extrapolating it.

A,, 13o) is round. At this point C, that distance!
Since mobile station MS8 is within the radius of zone 3,
is estimated to have moved to zone 3, and it can be seen that the optimal zone switching at point B is to switch to zone 3.

Based on this trajectory information, the zone switching control device 6 in FIG.
After switching from zone 3 to zone 3 and capturing the required new communication channel using existing technology, communication path control device 2 instructs communication path device 1 to switch to the new communication channel, and signal control device 3 It instructs the station Ml (83) to start communication with the mobile station MSS, while instructing the wireless base station MBSI to stop communication.As mentioned above, as the mobile station moves, the wireless This means that the zone has been switched from the old zone to the optimal new zone.

Although the above embodiment has been described with respect to a car telephone, it is equally applicable to other mobile communication systems such as airplanes and mobile phones, and not only to telephone communication but also to non-telephone communication systems.

As described above, according to the present embodiment, when switching from the current wireless zone to the next zone, by installing a device that stores the trajectory of the mobile device up to that point, It is possible to estimate the route and determine the wireless zone corresponding to the optimal wireless base station with which to communicate at the destination.

〔Effect of the invention〕

As explained above, according to the mobile communication zone switching method of the present invention, it is possible to switch to an optimal wireless zone by estimating the future course direction from the trajectory of the mobile device. This has the effect of reducing the number of switching operations and reducing the pressure on the processing capacity of the control channel and control processor.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram showing an overview of the zone switching method for mobile communications, FIG. 2 is a conceptual diagram showing an embodiment of the zone switching method for mobile communications according to the present invention, and FIG. 3 is the radio line control shown in FIG. 2. FIGS. 4(a) and 4(b) are block diagrams showing an example of the configuration of the station, and are side views of the configuration of the distance measuring packet frames for transmission and reception in FIG. 2. MSS...Mobile station, MBS1-3...Radio base station,
MC8... Radio channel control station, 1... Communication path device of radio channel control station, 2... Communication path control device, 3... Signal control device, 4... Trajectory information control device, 5. ...Storage device, 6...Zone switching control device. Agent Patent Attorney Tadashi Akimoto Minoru, 1j21 Figure 2 Figure 3 Figure 4 (a) MSS-MBS-MC5 (b)

Claims (1)

[Claims] In the zone switching method of mobile communication, in which the mobile device continues to communicate with the other device while switching the radio zone of the wireless base station with which it communicates as the mobile device moves, a means is provided for storing the trajectory of the movement of the mobile device, and the trajectory information is stored in the zone switching method. A zone switching system for mobile communications, comprising a means for estimating the route of a mobile device and determining and switching the wireless zone of a wireless base station with which to communicate at a destination.