JP2531356B2 - Base station with function to secure re-call slot at abnormal disconnection - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base station with a function to secure a recalled call slot during abnormal disconnection, and more particularly to a function of securing a slot for a recalled call after abnormal disconnection in a radio base station of a mobile communication network. Regarding base stations.

[0002]

2. Description of the Related Art In a mobile communication network, a mobile device performs wireless communication with a wireless base station. Although mobile telephones, mobile telephones, and the like are known as mobile devices of such mobile communication networks, in recent years, digital cordless telephones (PHP: Per) have been used.
The personal handy phone) became known. Although the output power of this PHP is weaker than that of a car phone or a mobile phone, one PHP can communicate with a plurality of parent devices, and the parent device used indoors is a public telephone as a wireless base station outdoors. It will be installed in boxes, telephone poles, etc.

Such a radio base station has basically the same configuration as a radio base station of a car telephone network, and is capable of multiplexing, for example, 4 calls per station by a time division multiple access system (TDMA). It is likely to be affected by an aerial medium such as interference, in which case a so-called abnormal disconnection may occur in which the call is disconnected against the intention of the caller. When this abnormal disconnection occurs, the mobile device (PHP), which has been talking until then, makes a call again.

[0004]

However, in the conventional radio base station, the lines are connected in the order in which the calls are made. Therefore, if the line is abnormally disconnected due to the above-mentioned interference or other air problems, the call is continued until then. If another mobile station makes a call before the mobile station that was doing the call recalls, the abnormally disconnected mobile station connects to the line and starts the call using the time slot that was being used up to that point. It will be.

Therefore, in the conventional radio base station, if the above-mentioned abnormal disconnection occurs when the traffic happens to be concentrated, it is difficult for the abnormally disconnected mobile unit to regain the communication slot and resume the call. Therefore, there is a problem that the call cannot be continued due to the re-call. Although obtaining a time slot has been known in the past (for example, Japanese Patent Laid-Open No. 2-206251), this method uses a time slot for the purpose of evenly using the slots among the nodes of the local area network. The time slot reservation reservation area is provided in the slot, and is not intended to continue the call in the mobile communication network.

The present invention has been made in view of the above points,
It is an object of the present invention to provide a base station with a function to secure a re-call slot for an abnormal disconnection, which solves the above-mentioned problem by securing a communication slot before the abnormal disconnection for a predetermined time when the abnormal disconnection occurs.

[0007]

In order to achieve the above-mentioned object, the present invention is a base station which wirelessly communicates with a mobile device using a time slot which is available at the time of calling, from the transmission signal of the mobile device to the mobile device. A storage unit that stores an identification number and a first unit that determines whether a call disconnection is an abnormal disconnection due to a problem on the air
And a slot securing means for securing a time slot at the time of disconnection when the abnormal disconnection is determined by the first determining means, and a second determining means and a call resuming means. It is configured.

The second determination means compares the identification number of the calling mobile device extracted from the call transmission signal of the mobile device within the set time with the identification number read from the storage unit, and is disconnected abnormally. It is determined whether the call is a re-call from the mobile device. The call resuming means reconnects to the other party using the reserved time slot for disconnection when the second determining means determines that the call is reissued from the mobile device that is abnormally disconnected. Is a means for restarting a call using a time slot.

[0009]

According to the present invention, when the base station determines by the first determining means that an abnormal disconnection has occurred due to a problem on the air in a state where the mobile station and the other party are communicating with each other via the base station. , The slot securing means secures the time slot for the set time. When the second determining means determines that there is a re-call from the abnormally disconnected mobile device within this set time, the call re-starting means restarts the call using the above-mentioned secured time slot. Even if the traffic volume is concentrated at the time of the call, the call can be immediately resumed within the set time.

[0010]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, a base station includes an antenna 1, a receiving unit 2 for receiving a signal from a mobile device, a demodulating unit 3 for demodulating a received signal, a channel codec unit 4, a modulating unit 5 for performing a predetermined modulation, and a modulated signal. Transmission unit 6 for converting into a predetermined signal band, control unit 7 for controlling / managing the entire call, PS of mobile device
A storage unit 8 for storing the ID and a comparing unit 9 for comparing the received PS-ID with the stored PS-ID.

Next, the operation of this embodiment will be described.
The base station is capable of multiplexing four calls per station, and when it receives a call from a mobile station such as a digital cordless telephone (not shown), it notifies the digital cordless telephone of an empty time slot. As a result, the digital cordless telephone modulates the voice signal for a call by a predetermined modulation method using the designated time slot and transmits it to the base station.

This transmission signal is received by the receiving section 2 via the antenna 1, further demodulated by the demodulating section 3 and then input to the channel codec section 4 to be converted into a voice signal. The PS-ID, which is a unique identification number of each digital cordless telephone in the demodulated signal, is stored in the storage unit 8 through the channel codec unit 4 and the control unit 7. This storage unit 8 stores PS-IDs for four calls.

The output signal of the channel codec unit 4 is transmitted to the other party via the exchange and the ISDN network. The voice signal from the other party is input to the channel codec section 4 through a route reverse to the above, is assigned to the time slot used under the control of the control section 7, and further from this, the modulation section 5, the transmission section 6 and It transmits to the calling side digital cordless telephone via the antenna 1. This enables a call.

The present embodiment is characterized by the control operation when there is a call disconnection. Next, this characteristic will be described with reference to the flowchart of FIG. That is, when the control unit 7 receives a disconnection request from the digital cordless telephone (step 101), it determines whether it is an abnormal disconnection due to a problem on the air (step 102). As for this judgment, for example, when the error rate of the demodulated signal deteriorates above a threshold value or when the received electric field strength sharply drops below a predetermined threshold value, it is judged to be abnormal disconnection. The first determining means is realized by the above step 102.

When the control section 7 determines that the cutting is abnormal,
For example, the built-in timer is started (step 103), the used time slot is secured (step 104),
After that, it is judged whether it is time-out (step 10).
5) It is determined whether or not a re-call from a mobile device (here, a digital cordless telephone) that has been abnormally disconnected within the timeout has been accepted (step 106).

The slot securing means can be realized by the steps 104 and 105, and the second judging means can be realized by the step 106. The time until the timeout described above is appropriately determined depending on the application and the like, but is, for example, about 10 seconds to 1 minute.

Whether the call is a re-call from the abnormally disconnected mobile unit is determined by the received PS-ID from the calling mobile unit within the time during which the timer is operating after the timer is started in step 103. And the stored PS-ID of the abnormally disconnected mobile device read from the storage unit 8 are compared based on the comparison result obtained by comparing and comparing the comparison unit 9, and if they match, control is performed. It is determined that the unit 7 has accepted the re-call from the mobile device that is abnormally disconnected.

When the control unit 7 judges that the re-call from the abnormally disconnected mobile unit is accepted, the line is connected using the time slot secured so far and the call is resumed (step 107). This step 107 is a step for realizing the call resuming means.

On the other hand, when the comparison result indicating the disagreement is input from the comparison unit 9 to the control unit 7, the control unit 7 determines that the call is made from a device other than the mobile unit which is abnormally disconnected in step 106. In this case, when the traffic volume is concentrated and the remaining three time slots except the reserved time slot are all in use, the control unit 7 rejects the call (step 108) and returns to step 105 again. Return Abnormal Return to the standby state for accepting a re-call from the disconnected mobile device.

At step 106, when it is determined that the control unit 7 has received a call from a mobile device other than the abnormally disconnected mobile device, among the remaining three time slots other than the secured time slot, an empty time slot is available. If there is, the empty time slot is allocated to allow the call between the calling mobile station and the other party (that is, the call is not rejected in this case). Then, in this case as well, the process returns to step 105 again to return to the state of waiting for re-call acceptance from the mobile device that is abnormally disconnected.

When it is determined in step 102 that the disconnection request is a normal disconnection request, the control unit 7 releases all time slots without securing time slots (step 109), and step 105. If it is determined that there is a time-out, it is determined that there is no re-call from the abnormally disconnected mobile device, and the time slot secured in step 104 is released (step 109).

In this way, according to the present embodiment, when a re-call is made from the abnormally disconnected mobile station before the time-out, the call is immediately continued using the reserved time slot. be able to.

[0023]

As described above, according to the present invention, by securing a time slot within the set time after the abnormal disconnection, the abnormally disconnected mobile unit makes a call by re-calling within the set time. Since it is possible to restart immediately, even if the traffic volume is concentrated at the time of the re-call of the abnormally disconnected mobile device, the call can be continued immediately,
Therefore, service operation can be improved as compared with the conventional one.

[Brief description of drawings]

FIG. 1 is a block diagram of one embodiment of the present invention.

FIG. 2 is a flow chart for the operation of one embodiment of the present invention.

[Explanation of symbols]

 1 Antenna 2 Receiver 3 Demodulator 5 Modulator 6 Transmitter 7 Control 8 Storage 9 Comparison

Claims (2)

(57) [Claims] 1. A base station that wirelessly communicates with a mobile device using a time slot that is vacant when a call is made, a storage unit that stores the identification number of the mobile device from a transmission signal of the mobile device, and a call disconnection over the air. A first determining means for determining whether or not the abnormal disconnection is caused by the above problem, and when the first determining means determines the abnormal disconnection,
A slot securing means for securing a time slot for disconnection for a set time , the identification number of the calling mobile device extracted from the call transmission signal of the mobile device within the set time, and the identification number read from the storage unit are compared. Second determining means for determining whether or not a re-call from the abnormally disconnected mobile device is made, and when the second determining means determines that the re-call is from the abnormally disconnected mobile device, the above-mentioned securement is performed. A base station with a slot securing function for re-calling at abnormal disconnection, which has means for reconnecting to the other party by using a time slot at disconnection and restarting a call. 2. The abnormal disconnection when the first determination means detects at least one of a case where an error rate of a demodulated signal deteriorates to a predetermined value or more and a case where a received electric field strength falls below a threshold value. The base station with the slot securing function for re-calling at the time of abnormal disconnection according to claim 1.