JP2002152109A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To avoid the erroneous judgement of communication possibility caused by the deterioration of radio channel quality or the like by shortening time for the judgement of communication possibility while effectively utilizing radio resources. SOLUTION: When judging possibility in communication by mutually exchanging a confirm signal and a response signal thereto among plural transmitters and receivers, when a data signal is transmitted, the exchange of the confirm signal and the response signal is replaced with the exchange of this data signal.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used for wireless communication in which the quality of a wireless channel between transmitters and receivers changes, such as mobile communication. The present invention relates to a technology for periodically determining whether communication is possible between a plurality of transceivers using a wireless line.

[0002]

2. Description of the Related Art In a wireless communication system in which the quality of a wireless link between a transmitter and a receiver changes, such as in mobile communication, it is determined whether or not communication is possible even when communication is not actually being performed. For example, if this determination result is notified to the user, the user can perform communication after moving to a place where communication is possible. Such a communication availability determination is called a health check, and a device for performing the health check is called a health check device.

FIG. 5 shows a configuration of a conventional transceiver, and FIG. 6 shows a configuration of a conventional health check device. FIG. 7 shows a conventional communication availability determination procedure. As shown in FIG.
The transceiver includes a transmission unit 1, a reception unit 2, a health check device 3, and a data transmission / reception unit 4. The transmission and reception of the data signal is performed by the data transmitting and receiving unit 4. In the health check device 3, the acknowledgment signal transmitting unit 20 shown in FIG. 6 periodically transmits an acknowledgment signal, and the communication availability determination unit 21 detects a response signal to the acknowledgment signal, thereby making a communication availability determination. Therefore, as shown in FIG. 7, in the conventional communication availability determination, an acknowledgment signal is transmitted to the other party at regular time intervals, and when a response is received, it is determined that communication with the other party transceiver is possible.

Here, a situation in which communication with the other party's transceiver is possible is, for example, that the other party's transceiver is in a range where radio waves can be reached or the power has not been cut off. For example, the situation in which the other party's transceiver is out of the range of radio waves or the power is turned off.

[0005]

In the conventional communication availability determination, a confirmation signal is always transmitted at regular time intervals. Therefore, if this time interval is shortened, the confirmation signal is transmitted frequently, and the effective use of radio resources is reduced. No, if you increase this time interval,
There is a problem that the time required until it is determined that communication with the other party's transceiver is impossible is long.

The present invention has been made in view of such a background, and an object of the present invention is to provide a radio communication system capable of shortening the time required to determine whether communication is possible while effectively utilizing radio resources. I do. An object of the present invention is to provide a wireless communication system that can avoid erroneous determination of communication availability due to deterioration of wireless channel quality and the like.

[0007]

SUMMARY OF THE INVENTION A wireless communication system according to the present invention is capable of transmitting and receiving a data signal when a plurality of transceivers mutually transmit and receive an acknowledgment signal and a response signal to determine whether communication is possible. In this case, the transmission and reception of the data signal is replaced with the transmission and reception of the confirmation signal and the response signal.

Thus, even if the transmission interval of the acknowledgment signal is shortened to shorten the time required to determine whether communication is possible, the acknowledgment signal is not transmitted during the data signal transmission / reception period. Since the number of transmissions of the acknowledgment signal can be reduced, it is possible to shorten the time required to determine whether communication is possible or not while effectively using wireless resources.

That is, the present invention includes a plurality of transceivers, and the transceiver includes a confirmation unit for periodically determining whether communication is possible between the transmission and reception units. The confirmation unit transmits a confirmation signal to a partner transceiver. Means for transmitting, and means for waiting for a response from the transmission time of the confirmation signal for a certain period of time, when there is a response, determining that communication with the other party transceiver is possible, and when there is no response, determining that communication with the other party transceiver is impossible. And a wireless communication system comprising:

Here, a feature of the present invention is that, when a data signal transmitted from the other party's transceiver is received within a predetermined time, there is provided means for stopping transmission of the confirmation signal by the transmitting means. The means for judging includes means for judging that communication with the partner transceiver is possible by receiving the data signal.

At this time, when the response to the acknowledgment signal is not within the predetermined time, there is provided a means for repeatedly executing the transmission of the acknowledgment signal to the counterpart transceiver for a predetermined number of times. It is preferable that a means is provided for determining that communication with the counterpart transceiver is impossible when there is no response from the counterpart transceiver even though the confirmation signal is transmitted the predetermined number of times.

[0012] This makes it possible to avoid erroneous determination due to failure to receive a response signal to a confirmation signal caused by a relatively short time degradation of radio channel quality or the like. In particular, in the present invention, since the transmission interval of the confirmation signal is set shorter than in the past, it is easily affected by temporary deterioration of the radio channel quality, but this configuration can avoid this.

Further, according to the present invention, one transceiver in the wireless communication system of the present invention is set as a master station,
The other plurality of transceivers are set as slave stations, and the checking means of the master station includes means for performing communication availability determination on the plurality of slave stations, and the checking means of the slave station includes: A wireless communication system may be provided that includes means for executing communication availability determination for the one master station.

[0014]

FIG. 1 shows a wireless communication system according to the present invention.
This will be described with reference to FIG. FIG. 1 is a block diagram of a health check device according to an embodiment of the present invention. FIG. 2 is a flowchart showing a procedure for determining whether communication is possible according to the first embodiment of the present invention. FIG. 3 is a flowchart showing a communication availability determination procedure according to the second embodiment of the present invention. FIG. 4 is an overall configuration diagram of a wireless communication system according to a third embodiment of the present invention. Although the configuration of the transceiver according to the embodiment of the present invention is common to the conventional configuration shown in FIG. 5, the internal configuration of the health check device is different.

As a first embodiment, as shown in FIG.
It has transceivers A and B, and the transceivers A and B
Comprises a health check device 3 for periodically determining whether or not communication is possible between the devices, and the health check device 3 includes a check signal transmitting unit 10 for sending a check signal to a partner transceiver.
A communication availability determination unit that waits for a response for a certain period of time from the transmission time of the confirmation signal, determines that communication is possible with the partner transceiver when there is a response, and determines that communication with the partner transceiver is not possible when there is no response. 11 is a wireless communication system including

Here, a feature of the present invention is that, as shown in FIG. 1, when a data signal transmitted from a partner transceiver is received within a predetermined time, an acknowledgment signal transmitting unit 1 is provided.
A confirmation signal transmission control unit 12 for stopping the transmission of the confirmation signal of 0 is provided, and the communication availability determination unit 11 determines that communication with the partner transceiver is possible by receiving the data signal.

In a second embodiment, the acknowledgment signal transmission control unit 12 repeatedly transmits the acknowledgment signal to the partner transceiver a predetermined number of times when the response to the acknowledgment signal is not within the predetermined time. Then, the communication availability determination unit 11 determines that communication with the partner transceiver is not possible when there is no response from the partner transceiver even though the confirmation signal is transmitted the predetermined number of times.

As a third embodiment, as shown in FIG.
In the wireless communication system of the first or second embodiment, one transceiver is set as a master station, and other transceivers are set as slave stations, and the health check device 3 of the master station includes a plurality of slave stations. The communication availability determination is performed for the station, and the health check device 3 of the slave station performs the communication availability determination for the one master station.

Hereinafter, embodiments of the present invention will be described in more detail.

(First Embodiment) A first embodiment will be described with reference to FIGS. 1, 2 and 5. FIG. As shown in FIG. 5, the wireless communication system according to the present invention includes a plurality of transceivers A and B. One transceiver A, B includes a transmitter 1,
It comprises a receiving unit 2, a health check device 3, and a data transmitting / receiving unit 4. The health check device 3 includes a confirmation signal transmission unit 10, a communication availability determination unit 11, and a confirmation signal transmission control unit 12, as shown in FIG.

As shown in FIG. 2, the transceiver A operates at time T
The data signal from the transceiver B is monitored in units, and if the data signal from the transceiver B is received within the time T, it is determined that communication with the transceiver B is possible.

If the data signal is not received from the transceiver B within the time T, a confirmation signal requesting a response is transmitted to the transceiver B, and the transceiver B is transmitted for the time Ta.
Wait for a response signal from. If the response signal returns within the time Ta, it is determined that communication with the transceiver B is possible. If there is no response signal from the transceiver B within the time Ta, it is determined that communication with the transceiver B is not possible. The same procedure is performed in the transceiver B.

(Second Embodiment) A second embodiment will be described with reference to FIG. In the second embodiment, as shown in FIG. 3, the data signal from the transceiver B was not received within the time T, and the confirmation signal requesting a response was transmitted, but the response signal did not return within the time Ta. In this case, a confirmation signal requesting a response is transmitted again, and a response is again waited for a time Ta. If the response signal returns within a predetermined number of times (two in FIG. 3) of the transmission of the confirmation signal requesting the response, it is determined that communication with the transceiver B is possible.

Further, even if the number of transmissions of the confirmation signal requesting a response reaches a predetermined number of times, if there is no response from the transceiver B within the time Ta, it is determined that communication with the transceiver B is impossible. The same procedure is performed in the transceiver B.

(Third Embodiment) A third embodiment will be described with reference to FIG. In the third embodiment, as shown in FIG. 4, the transceiver A of the first or second embodiment is a master station, the transceiver B is a slave station, and the master station (transmitter / receiver A) has a plurality of slave stations. It monitors whether (Transceiver B) is in a position where radio waves can reach or whether the power has been turned off. Similarly, each slave station (transmitter / receiver B) monitors whether the master station (transmitter / receiver A) is located at a position where radio waves can reach or whether the power has been turned off.

If the configuration of the third embodiment is used, a cordless phone system or a PH used in a home or an office can be used.
The present invention can be applied to an S (Personal Handy phone System) or a mobile phone system.

[0027]

As described above, according to the present invention,
It is possible to shorten the time required to determine whether communication is possible while effectively using wireless resources. Further, it is possible to avoid erroneous determination as to whether or not communication is possible due to deterioration of wireless channel quality or the like.

[Brief description of the drawings]

FIG. 1 is a block diagram of a health check device according to the present invention.

FIG. 2 is a flowchart illustrating a communication availability determination procedure according to the first embodiment;

FIG. 3 is a flowchart illustrating a communication availability determination procedure according to a second embodiment;

FIG. 4 is a diagram showing an entire configuration of a third embodiment.

FIG. 5 is an overall configuration diagram of a wireless communication system.

FIG. 6 is a block diagram of a conventional health check device.

FIG. 7 is a flowchart showing a conventional communication availability determination procedure.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transmission part 2 Receiving part 3 Health check device 4 Data transmission / reception part 10, 20 Confirmation signal transmission part 11, 21 Communication availability judgment part 12 Confirmation signal transmission control part A, B transceiver

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Yoshitaka Shimizu 2-3-1 Otemachi, Chiyoda-ku, Tokyo Nippon Telegraph and Telephone Corporation F-term (reference) 5K011 GA01 JA01 KA12 KA13 LA02 5K067 AA13 AA14 AA33 BB04 BB08 DD24 EE02 EE10 EE25 GG01 GG11 HH21

Claims (3)

[Claims] 1. A communication system comprising: a plurality of transceivers; and a confirmation means for periodically determining whether communication is possible between the transceivers. The confirmation means includes means for transmitting a confirmation signal to a partner transceiver. Means for waiting for a response for a certain period of time from the transmission time of the confirmation signal, determining that communication is possible with the partner transceiver when there is a response, and determining that communication with the partner transceiver is not possible when there is no response. In a wireless communication system, when a data signal transmitted from a partner transceiver is received within a predetermined time, a means for stopping transmission of the acknowledgment signal of the transmitting means is provided. A wireless communication system, comprising: means for determining that communication is possible with a counterpart transceiver by reception. 2. When the response to the acknowledgment signal is not within the fixed time period, the acknowledgment means includes means for repeatedly transmitting the acknowledgment signal to the counterpart transceiver for a predetermined number of times. 2. The wireless communication system according to claim 1, further comprising: means for determining that communication with the other party's transceiver is impossible when there is no response from the other party's transceiver despite the predetermined number of transmissions. 3. The wireless communication system according to claim 1, wherein one transceiver is set as a master station, and a plurality of other transceivers are set as slave stations. Means for executing a communication availability determination for the slave station, wherein the confirmation means of the slave station includes means for performing a communication availability determination for the one master station. Wireless communication system.