JPH11122321A - Data communication system using mobile terminals - Google Patents

Abstract

(57) [Summary] Data communication using a mobile terminal capable of realizing a higher bearer speed than the currently provided bearer speed without changing the structural function of a network infrastructure that requires a huge investment cost. Provide a method. In a data communication system using a mobile terminal, a function having a capability of independently establishing, maintaining, and releasing a plurality of calls using different telephone numbers is provided on the side of the mobile terminal; Has a multi-link point-to-point protocol using a plurality of links and a terminal adapter function having a bandwidth allocation control protocol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a data communication system using a mobile terminal.

[0002]

2. Description of the Related Art Data communication services are currently provided using mobile communication terminals. These are one communication call (ca
In most cases, a fixed information rate is provided for ll). In addition, the actual communication speed called the throughput varies depending on the state of the error in the transmission path. For example, the cellular communication system PDC (Personal Digit
al Cellular), up to 28.8 Kbit / s for one call
Packet data service that achieves
PHS (Personal Handy phone System) has 32Kbit / s
Data transmission service PIAFS (PHS Intemet) that realizes a maximum throughput of 29.2 Kbit / s by applying error control to
rnet Access Forum Standard) is provided.

[0003]

[Problems to be solved by the invention]

(1) Cost of providing high-speed data transmission With the development of multimedia technology, higher-speed data communication services are required not only for fixed communication but also for mobile communication. In this case, as an effect on the system, a request for improvement of a network infrastructure such as a base station usually requires a large cost for replacement / repair and it is difficult to quickly respond. (2) Disconnection at the time of handover In the current mobile communication system, there is a problem that instantaneous interruption occurs every time a terminal switches a connection destination base station (handover), and data transmission becomes impossible during this time.

[0004] It is an object of the present invention to provide a mobile terminal capable of realizing a higher bearer rate than the currently provided bearer rate without changing the structural functions of the network infrastructure, which requires a huge investment cost. It is to provide a data communication method using the data communication method.

[0005]

In order to achieve this object, a data communication system using a mobile terminal according to the present invention comprises:
In a data communication system using a mobile terminal, a function having the capability of independently establishing, maintaining, and releasing a plurality of calls using different telephone numbers on the side of the mobile terminal, and being established on the plurality of calls. It has a configuration characterized by having a multilink point-to-point protocol using a plurality of links and a terminal adapter function having a bandwidth allocation control protocol.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, a mobile terminal establishes a number of calls corresponding to a required transmission rate, and allocates data transmission distributed by a multi-link protocol to each call, thereby realizing a network infrastructure. High-speed data transmission that cannot be realized by the conventional technology can be realized without changing the structure. In addition, independent handover control of each call to avoid simultaneous handover of all communication calls enables continuous data transmission without instantaneous interruption while changing the effective transmission speed. This is an advantage of the present invention that cannot be obtained when performing high-speed data communication with a single call.

[0007]

An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a 32Kbit / s per call on a wireless transmission path.
ADPCM A PHS system capable of voice and data transmission, using a portable terminal that can handle two calls at the same time and providing a transmission path of up to 64 Kbit / s by way of example,
1 shows a configuration of the present invention.

In FIG. 1, a portable terminal S101 has the functions of two conventional PHS terminals, and has a function of independently handling two calls. The terminal is also assigned two telephone numbers. These are # DN1 and # DN2. S103 is PHS
Can support data communication protocol for
A TA (Terminal Adapter) that supports the conventional data communication service PIAFS protocol and is based on the Internet standard RFC 1990, PPP (Point to Point Pr
otocol) Multilink Protocol (MP) and standard RF
Bandwidth allocation control protocol (BAP, BACP) based on C2125
Is implemented. ISDN for terminal adapter S106 for PHS
A terminal adapter (TA) connected to the subscriber line S110 and having the same function as the terminal adapter S103. The base station S102 is a PHS base station and can usually handle three independent calls.

<Calling phase> When the mobile terminal S101 attempts to perform data communication, the mobile terminal S101 first starts the server S1.
Make a call to the telephone number # DNS1 of 07. As a result, an information transmission path of 32 Kbit / s is secured between [wireless transmission path S108-PHS access system S109-PHS / ISDN network S105-ISDN subscriber line S110]. Thereafter, the data communication service PI is transmitted between the [terminal adapters S103 and S106] by mutual signal transmission between the [PHS terminal adapter S103 and the PHS terminal adapter S106].
When the AFS protocol is established, [Terminal adapter S1
03-S106], data communication at a maximum of 29.2 Kbit / s can be performed. At the same time, by using the link control protocol authentication option exchanged when the point-to-point protocol PPP is established, the multilink protocol MP between the [PHS terminal adapters S103-S106] is used.
Make sure it is compatible.

<64 Kbit / s transmission line link establishment phase>
Subsequently, the mobile terminal S101 uses the terminal function of another terminal to call the telephone number # DNS1 of the server S107. The receiving side is IS
This call is received by the other B-ch of the DN and passed to the PHS terminal adapter S106. This PHS Terminal Adapter S1
06 recognizes that a packet passing through this link has the same protocol identifier as the protocol identifier on the link established earlier, and confirms that this link is a multilink. In this way, the PHS terminal adapter S106
Establishes a 64 Kbit / s logical channel that bundles PHS transmission links for two B-chs.

<Handover Phase> When the quality of the transmission path deteriorates, for example, when the terminal moves closer to the outside of the communicable range of the base station, a handover is required. FIG.
FIG. 3 is a block diagram for explaining a handover procedure in this case. Need for handover is mobile terminal S101
May be determined, or the terminal adapter S103 may determine. When handover is required for both lines, the handover is always started in the order of poorer transmission path conditions such as worse line quality. In any case,
At this time, the PHS terminal adapter S103 disconnects the link on the handover call prior to the handover.
This link disconnection is performed by performing mutual signal transmission using the bandwidth allocation control protocol BAP or by using LCP (LinK Control
l Protocol: A link control protocol is used to notify the other party S106 of the link disconnection. When the handover is successful and the line via the new base station S112 is connected, the terminal adapter S103 on the portable terminal S101 establishes a link again by the multilink protocol MP. After the link is established, 64 Kbit / s communication can be performed again using two 32 Kbit / s links.

As described above, the link is disconnected during the handover, but if the handover does not occur simultaneously on two lines, the worst one 32 Kbit / s link can be secured. This is shown in FIG.

In the above example, a PHS system is used.
Although only the method of transmitting 64 Kbit / s has been illustrated, if the portable terminal is configured to handle more calls, the present invention can be applied to further transmit at 128 Kbit / s or higher. Also, an arbitrary data processing and transmitting device such as a digital camera and a video device can be connected to the terminal.

[0014]

As described above, according to the present invention,
It is possible to provide a higher bearer rate than the currently provided bearer rate without waiting for the upgrade of the network infrastructure, which is a huge investment cost. Further, if the handover method described in the present invention is adopted, data communication has always been momentarily interrupted at the time of handover, but continuous data communication becomes possible from the viewpoint of an application, and its practical effect is extremely large. .

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a mobile data communication system of the present invention applied to 64 Kbit / s using PHS.

FIG. 2 is an example of a sequence illustrating a handover according to the present invention.

FIG. 3 is an example of a change in the effective transmission rate at the time of handover according to the configuration of the present invention using two 32 Kbit / s links.

[Explanation of symbols]

 S101 PHS terminal S102, S212 PHS base station S103 PHS compatible TA (terminal adapter) S104 remote access terminal S105 PHS / ISDN network S106 PHS compatible TA (terminal adapter) S107 server S108 wireless transmission path S109 PHS access system S110 ISDN subscriber line

Claims (2)

[Claims] 1. A data communication system using a mobile terminal, wherein the mobile terminal has a function capable of independently establishing, maintaining, and releasing a plurality of calls by using different telephone numbers; A mobile data communication system using a mobile terminal, comprising: a multilink point-to-point protocol using a plurality of links established above; and a terminal adapter function having a bandwidth allocation control protocol. 2. The portable terminal has a function of controlling handover, and when a handover is required for a call forming the plurality of calls, a multilink is individually formed for the call. 2. The system according to claim 1, wherein the handover function is activated after disconnecting the link to be performed, and control for maintaining the multilink is performed by reestablishing the link after the handover is completed. A mobile data communication system using the mobile terminal described in the above.