JP2001285930A - Wireless communication terminal and wireless communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress deterioration in communication quality in the case that a channel whose throughput is comparatively deteriorated is started as a start channel. SOLUTION: When the mobile phone terminal 1 detects that the throughput of a channel 11 started as the start channel is comparatively deteriorated while the mobile phone terminal 11 has started the channel 11 provided by a base station (A) 11 as the start channel 11, the mobile phone terminal 1 starts a channel 21 newly provided by a base station (B) 12 as the start channel and uses the channel 21 started as the new start channel after that to make communications with the base station (B) 12. When the throughput of the channel 21 started as the new start channel is comparatively well, the communication quality is not deteriorated after that and thus the deterioration in the communication quality can be suppressed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication terminal such as a portable telephone terminal and a radio communication system comprising the above radio communication terminal and a base station.

[0002]

2. Description of the Related Art Conventionally, wireless communication terminals such as mobile telephone terminals and vehicle-mounted telephone terminals have been widely used. By activating any one of a plurality of channels as an activation channel, this type of wireless communication terminal can communicate with a base station using the channel activated as an activation channel. It has a possible configuration.

However, in this case, if a channel having a relatively low throughput among a plurality of channels is activated as an activation channel, a channel having a relatively low throughput is used thereafter to communicate with a base station. Communication has to be performed between the devices, which causes a problem that the communication quality is degraded.

The present invention has been made in view of the above circumstances, and has as its object to reduce the communication quality even when a channel whose throughput is relatively poor is activated as an activation channel. It is an object of the present invention to provide a wireless communication terminal and a wireless communication system that can suppress the operation.

[0005]

According to the radio communication terminal of the present invention, the control means activates any one of the plurality of channels as an activation channel and activates the channel as an activation channel. When it is detected that the throughput is below a predetermined level, another channel is newly activated as an activation channel.

[0006] That is, according to this, when it is detected that the throughput of the channel activated as the activation channel is equal to or lower than a predetermined level, another channel is activated as an activation channel, and thereafter, a new activation is performed. Since communication is performed with the base station using another channel activated as a channel, if the throughput of another channel newly activated as a startup channel exceeds a predetermined level, the Thereafter, the communication quality does not decrease, thereby suppressing the communication quality from decreasing.

According to the second aspect of the present invention, when the control means detects that the throughput of the channel activated as the activation channel is equal to or lower than a predetermined level, the control means newly identifies the adjacent station. The channel provided by the base station is activated as an activation channel.

That is, according to this, when it is detected that the throughput of a channel activated as an activation channel is equal to or lower than a predetermined level, a channel provided by a base station newly identified as an adjacent station is activated. And then communicates using the channel newly activated as the activation channel, so that the channel provided by the base station identified as an adjacent station newly activated as the activation channel If the throughput exceeds a predetermined level, it is possible to suppress a decrease in communication quality thereafter in the same manner as the above-described claim 1.

In this case, instead of activating a channel provided by a base station newly identified as its own station as an activation channel, a channel provided by a base station newly identified as an adjacent station is activated. Since it is configured to be activated as a channel, a channel provided by a base station different from the base station providing a channel whose throughput is equal to or lower than a predetermined level is activated as a new activation channel. It is possible to increase the probability that the throughput of the set channel exceeds a predetermined level and increase the probability that the communication quality can be prevented from deteriorating.

According to the third aspect of the present invention, the control means detects the time from when the I-frame is transmitted to the base station to when the RR-frame is received from the base station, so that the control means can be used as an activation channel. Detect the throughput of the activated channel.

[0011] That is, according to this, by detecting the time from when the I frame is transmitted to the base station to when the RR frame is received from the base station, the throughput of the channel activated as the activation channel can be reduced. Because it is configured to detect the existing I frame and R
By using the R frame, it is not necessary to define a new frame to communicate with the base station, and the throughput of the channel activated as the activation channel can be detected relatively easily.

According to the wireless communication terminal of the fourth aspect, the control means receives the traffic information from the base station and analyzes the received traffic information to reduce the throughput of the channel activated as the activation channel. To detect.

[0013] That is, according to this configuration, since the traffic information is received from the base station and the received traffic information is analyzed, the throughput of the channel activated as the activation channel is detected. When compared with the above-described claim 3,
It is not necessary to transmit the I frame to the base station, and the throughput of the channel activated as the activation channel can be detected.

According to a fifth aspect of the present invention, there is provided a wireless communication system comprising the wireless communication terminal according to the fourth aspect and a base station for transmitting traffic information to the wireless communication terminal. By receiving the traffic information from the base station and analyzing the received traffic information, it is possible to detect the throughput of the channel activated as the activation channel.

When it is detected that the throughput of the channel activated as the activation channel is equal to or lower than a predetermined level, another channel is activated as an activation channel, and thereafter, the other channel is activated as a new activation channel. Since the communication is performed using the channel of the first channel, if the throughput of another channel newly activated as the activation channel exceeds a predetermined level, thereafter, the configuration described in claim 1 will be used. Similarly,
A decrease in communication quality can be suppressed.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) A first embodiment in which the present invention is applied to a portable telephone terminal will be described with reference to FIG.
This will be described with reference to FIG. First, FIG. 1 schematically shows an electric functional block of a mobile phone terminal and a configuration of a network. In the mobile phone terminal 1, C
The PU 2 (control means in the present invention) includes a wireless circuit 3 for performing wireless processing, a voice circuit 6 for performing voice processing of a transmission voice input by the microphone 4 and a reception voice output by the receiver 5, and a telephone circuit for starting a call. A keypad 7 having a number of keys such as a "call start" key, an "end call" key for ending a call, and a "numeric" key for inputting numbers "0" to "9"; A display 8 for displaying various display information and a memory 9 for storing various storage information are connected.

The mobile phone terminal 1 is connected to the mobile phone network 1
For example, the service area of the base station (A) 11 and the service area of the base station (B) 12 at 0 are located in an overlapping area, whereby the base station (A) 11 and the base station (B) 12 It is possible to perform handover between the two base stations.

Next, the operation of the above configuration will be described with reference to FIG.
5 will be described with reference to FIG. Here, it is assumed that the mobile telephone terminal 1 has identified the base station (A) 11 as its own station and has identified the base station (B) 12 as an adjacent station. Then, the mobile phone 1 is, as shown in FIG.
By activating, for example, channel 11 among the n channels of channels 11 to 1n provided by the base station (A) 11 identified as the own station as a start channel, communication with the base station (A) 11 is started. In response to this, the base station (B) 12 identified as (n-1) channels from channel 12 to channel 1n provided by the base station (A) 11 and the adjacent station is Channels 21 to provide
Assume that n channels of channel 2n have been identified as activation candidate channels that are candidates for activation channels.

In the portable telephone terminal 1, during communication with the base station (A) 11, the CPU 2 determines whether or not a request (event) for transmitting an I frame (information frame) has occurred. If it is determined that a request to transmit an I frame has occurred (step S1), "YES" is determined in step S1, and the I frame is transmitted to the base station.
(A) Transmit to 11 (step S2). And CPU
At about the same time, 2 clears (initializes) the counter (step S3) and starts the timer (step S4).

The CPU 2 transmits the I frame to the base station (A) 11 until the timer expires, and as shown in FIG.
It is determined whether an RR frame (receivable frame) has been received from step 11 (steps S5 and S6).

When the CPU 2 detects that the RR frame has been received from the base station (A) 11 before the timer expires, the CPU 2 determines "Y" in step S5.
ES ”and stop the timer (step S
7) Returning to step S1, it is determined again whether a request to transmit an I frame has been issued.

On the other hand, the CPU 2 has the base station (A) 1
If it is detected that the timer has expired before receiving the RR frame from No. 1, it is determined to be "YES" in step S6, and the count value is incremented (step S8).

Then, the CPU 2 determines whether or not the count value has exceeded the threshold value (step S9). If the count value has not exceeded the threshold value, the CPU 2 determines "N" in step S9.
O ", the timer is reset (restarted) (step S11), the process returns to step S5, and the RR frame is received again from the base station (A) 11 until the timer expires. It is determined whether or not (steps S5 and S6).

On the other hand, if the count value exceeds the threshold value, CPU 2 determines “YES” in step S 9.
Is determined, and a new channel different from the channel activated as the activation channel at that time is activated as an activation channel (step S11), and the process returns to step S1 described above, and a request for transmitting an I frame is generated again. It is determined whether or not it has been performed.

More specifically, since the CPU 2 activates the channel 11 provided by the base station (A) 11 as an activation channel, the CPU 2 identifies it as its own station as shown in FIG. For example, among the (n-1) activation candidate channels provided by the base station (A) 11 and the n activation candidate channels provided by the base station (B) 12 identified as adjacent stations, for example, channel 21 is used. Start as a new start channel.

As described above, the portable telephone terminal 1 transmits the I frame to the base station while the channel 11 provided by the base station (A) 11 is activated as the activation channel.
(A) When the RR frame is not received from the base station (A) 11 within a predetermined time after being transmitted to the base station (A) 11, it is determined that the throughput of the channel 11 activated as the activation channel is relatively poor. Instead of the channel 11 provided by the station (A) 11, for example, the channel 21 provided by the base station (B) 12 newly identified as an adjacent station is activated as an activation channel.

In the above description, the configuration in which the base station (A) 11 is identified as its own station and the base station (B) 12 is identified as an adjacent station is described. Even when the base station (B) 12 is identified as its own station and the base station (A) 11 is identified as an adjacent station, the same processing is performed.

In the above description, the channel 11 provided by the base station (B) 12 newly identified as an adjacent station replaces the channel 11 provided by the base station (A) 11 identified as its own station. Although the description has been given of the configuration in which the base station (A) 11 newly identified as its own station is activated, for example, the channel 12 other than the channel 11 provided by the base station (A) 11 is activated as the activation channel. It is also possible.

In the above description, a configuration is described in which only one base station (B) 12 is identified as an adjacent station. However, a plurality of base stations identified as adjacent stations may be used. If a station exists, it is also possible to configure so that any channel provided by any one of the plurality of base stations identified as the adjacent stations is activated as an activation channel. .

As described above, according to the first embodiment, when the channel 11 provided by the base station (A) 11 is activated as the activation channel, the throughput of the channel 11 activated as the activation channel Is relatively poor, a new base station (B) 1
2 is activated as an activation channel, and thereafter, communication is performed with the base station (B) 12 using the channel 21 newly activated as an activation channel. If the throughput of the channel 21 activated as the activation channel is relatively good, the communication quality does not decrease thereafter, and the decrease in the communication quality can be suppressed.

In this case, instead of activating a channel provided by the base station (A) 11 newly identified as its own station as an activation channel, a base station (A) newly identified as an adjacent station is not activated. Since the channel 21 provided by B) 12 is configured to be activated as an activation channel, the base station (B) 12 which is different from the base station (A) 11 which provides a channel whose throughput is relatively poor is provided. Since the channel 21 is newly activated as the activation channel, the probability that the throughput of the channel 21 newly activated as the activation channel is relatively good can be increased, and a decrease in communication quality can be suppressed. Probability can be increased.

Further, in this case, the I frame is transmitted to the base station.
(A) By detecting the time from transmitting to the base station (A) 11 to receiving the RR frame from the base station (A) 11,
Since the configuration is such that the throughput of the channel 11 activated as an activation channel is detected, a frame to be newly communicated with the base station (A) 11 is defined by using the existing I frame and RR frame. Therefore, the throughput of the channel 11 activated as the activation channel can be detected relatively easily.

Second Embodiment Next, a second embodiment of the present invention will be described.
An embodiment will be described with reference to FIGS.
The description of the same parts as in the first embodiment is omitted,
Hereinafter, different parts will be described. In the above-described first embodiment, by detecting the time from transmitting the I frame to the base station (A) 11 to receiving the RR frame from the base station (A) 11, it is activated as an activation channel. In contrast, in the second embodiment, the traffic information is received from the base station (A) 11 as shown in FIG. By analyzing the traffic information obtained, the throughput of the channel 11 activated as the activation channel is detected.

That is, in the portable telephone terminal 1, the CP
During communication with the base station (A) 11, U2 determines whether or not traffic information has been received from the base station (A) 11 (step S21). When it is detected that the traffic information has been received, step S
21 is determined to be "YES", and the received traffic information is analyzed (step S22).

If the traffic value indicating the load on the base station (A) 11 exceeds the threshold value as a result of analyzing the traffic information, the CPU 2 determines “YES” in step S23, and In the same manner as in the first embodiment, a new channel different from the channel currently activated as the activation channel is activated as the activation channel (step S24), the process returns to step S21, and the base station (A ) It is determined whether or not traffic information has been received from 11.

As described above, the mobile telephone terminal 1 receives the traffic information from the base station (A) 11 while activating the channel 11 provided by the base station (A) 11 as an activation channel, and When the value exceeds the threshold value, it is determined that the throughput of the channel 11 activated as the activation channel is relatively poor, and another channel is newly provided in place of the channel 11 provided by the base station (A) 11. Is activated as an activation channel.

In this case, in the portable telephone terminal 1,
It is also possible to store a threshold value serving as a criterion as a fixed value in the memory 9, and the base station (A) 11 transmitting the traffic information may be configured according to the form and load of the communication system. By transmitting the threshold value, it is also possible to configure so that the threshold value serving as a criterion is stored in the memory 9 as a variable value.

Further, the base station (A) 11 can be configured to actively transmit traffic information to the portable telephone terminal 1 at regular intervals, for example, by using a time as a trigger. By receiving a request from the mobile phone 1 as a trigger, traffic information can be passively transmitted to the mobile phone 1.

As described above, according to the second embodiment, the same functions and effects as those of the first embodiment can be obtained. In particular, in this case, the traffic information is received from the base station (A) 11, and the received traffic information is analyzed to detect the throughput of the channel 11 activated as the activation channel. Compared to the first embodiment described above,
It is not necessary to transmit the I frame to the base station, and the throughput of the channel 11 activated as the activation channel can be detected.

(Other Embodiments) The present invention is not limited to the above embodiment, but can be modified or expanded as follows. As a wireless communication terminal,
The present invention is not limited to the mobile phone terminal, and may be a vehicle-mounted phone terminal. In the first embodiment, the channel may be an information channel or a user packet channel. In the second embodiment, the channel is not limited to the information channel or the user packet channel. It may be a channel.

[Brief description of the drawings]

FIG. 1 schematically shows a first embodiment of the present invention.

FIG. 2 shows a local station channel and an adjacent station channel.

FIG. 3 is a flowchart showing control contents.

FIG. 4 is a sequence diagram

FIG. 5 is a diagram corresponding to FIG. 2;

FIG. 6 is a flowchart showing control contents according to a second embodiment of the present invention.

FIG. 7 is a diagram corresponding to FIG. 4;

[Explanation of symbols]

In the drawing, 1 is a mobile phone terminal (wireless communication terminal), 2 is a CP
U (control means), 11 is a base station (A) (base station), and 12 is a base station (B) (base station).

Claims (5)

[Claims] 1. A wireless system comprising: control means for activating any one of a plurality of channels as an activating channel and performing communication with a base station using the channel activated as the activating channel. In the communication terminal, when the control unit detects that the throughput of a channel activated as an activation channel is equal to or lower than a predetermined level, the control unit newly activates another channel as an activation channel. . 2. The control unit, when detecting that the throughput of a channel activated as an activation channel is equal to or lower than a predetermined level, sets a channel provided by a base station newly identified as an adjacent station to an activation channel. The wireless communication terminal according to claim 1, wherein the terminal is activated. 3. The control means detects the time from transmitting an I frame to a base station to receiving an RR frame from the base station, thereby detecting the throughput of the channel activated as the activation channel. The wireless communication terminal according to claim 1, wherein: 4. The control unit according to claim 1, wherein the control unit receives traffic information from a base station, and analyzes the received traffic information to detect a throughput of a channel activated as an activation channel. 1
Or the wireless communication terminal according to 2. 5. A wireless communication system, comprising: the wireless communication terminal according to claim 4; and a base station that transmits traffic information to the wireless communication terminal.