JP2001078257A - System for reducing waiting transition time - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a system for reducing a waiting transition time where a time required for failure in a waiting channel selection processing is reduced by increasing a hit rate of the waiting channel selection processing with respect to the system for reducing waiting transition time so as to reduce a time until an in-zone waiting state transition. SOLUTION: The system is provided with a perch channel usage rate storage means 11 placed in a mobile station and storing a usage rate of a perch channel and with a perch channel selection means 12 that preferentially selects a perch channel with a high usage rate obtained from the perch channel usage rate storage means 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a system for reducing standby travel time, and more particularly to a system for reducing standby travel time in a digital mobile telephone system (PDC system).

[0002]

2. Description of the Related Art FIG. 9 is a conceptual diagram of wireless channel switching in a PDC system. In the figure, reference numeral 1 denotes a mobile station (cellular phone device), which shows an example mounted on a car. Reference numeral 2 denotes a base station, which indicates a base station A and a base station B. Point A is a voice communication start point, and point B is a voice communication end point. In the figure, “CCH” indicates a control physical channel, “TCH” indicates a communication physical channel, and 3 indicates a zone where radio waves of a specific station reach.

In the figure, the level at point A is 100c
h, 200ch, 300ch, 400ch, 600c
h, 500 ch, and the level at point B is 4
The order is 00 ch, 100 ch, 300 ch, and 500 ch.

A mobile station (a mobile telephone device in a PDC system) communicates with a base station (a device on the network side in the PDC system that performs wireless communication with the mobile station) by using a wireless channel (a wireless communication device). The control physical channel (a channel for receiving an incoming call or network information from a communication partner), a communication physical channel (a channel used for voice communication), and a packet communication physical channel (a packet There is a communication channel), and the mobile station 1 performs communication by properly using the wireless channel.

[0005] Normally, the mobile station 1 waits for an incoming call or an outgoing call on a control physical channel (hereinafter referred to as a service waiting state).
In voice communication and packet communication, the wireless channel is switched from the control physical channel to the communication physical channel and the packet physical channel, and communication is performed. Works to go back.

When the mobile station 1 is powered on, the communication ends (end of communication using the communication physical channel or the packet physical channel), and when the zone shifts (switches the base station with which communication is performed during standby), the mobile station 1 is in the standby state. Since the control physical channel to be used sometimes is not known, it is necessary to search for an available control physical channel (a state in which the control physical channel is searched is called an out-of-service state).

The process of searching for the control physical channel includes:
There are perch channel scan processing and standby channel selection processing. In the perch channel scanning process, an operation of measuring a radio level of a predetermined control physical channel (hereinafter referred to as a perch channel) for receiving information from the network and selecting a radio channel having a level higher than the usable level is performed. Perform

In the standby channel selection process, the perch channel selected in the perch channel scanning process is opened, and information on the control radio channel used in the standby mode is obtained from the network, and the control physical channel is opened. Perform the operation.

In order to shift from the power-on state to the area standby state, a perch channel scanning process is executed,
The standby channel selection process is performed using the perch channel selected here. At the end of communication or at the time of zone transition, during communication or in the standby state during communication, since perch channel information is notified from the network, only the standby channel selection process is executed using the perch channel information,
The perch channel scanning processing is omitted, and the operation is performed so as to shorten the time required for transition to the area waiting state.

In the standby channel selection processing, processing is performed on the perch channel information notified from the network. At this time, if the processing fails and it is not possible to shift to the in-service standby state, the perch channel scanning processing is performed. To work.

FIG. 10 is a functional block diagram of a conventional PDC radio control unit. The details will be described below. In the figure, a PDC software radio control unit 100 maintains a radio state in a mobile station. PDC control memory 300
Is a memory area for the PDC software radio control unit 100 to perform processing. The perch channel scan control unit 101 is a control unit that performs a perch channel scan process, measures the reception level of the perch channel set in the perch channel storage area 301 with the level measuring device 200, and determines whether or not it can be used. Level perch channel is detected.
2 is stored.

The perch channel storage area 301 is an area for storing perch channel information measured by the perch channel scan control section 101, and the perch channel table 302 based on the detection level is stored in the perch channel scan control section 101. 9 is a table in which detected perch channels are associated with reception levels and sorted in descending order of reception level. Level measuring device 200 is a device that measures a reception level.

The standby channel selection control unit 102 is a control unit that performs a standby channel selection process, and is a perch channel state control unit that is a perch channel stored in the detection level sequential perch channel table 302 or another control unit. 103, network information (hereinafter referred to as broadcast information) for sequentially opening the perch channels for the perch channels specified by the voice communication control section 104 and the packet communication control section 105, and shifting to an area waiting state. Is received, and if the process is successful, the in-service waiting state control unit 103 is activated. If there is no perch channel to be processed and the process fails, the perch channel scan control unit 101 is activated. To work.

In the figure, the in-zone standby state control unit 103
The radio communication control unit 104 performs radio control during standby in the area, the voice communication control unit 104 performs radio control of communication using the communication physical channel, and the packet communication control unit 105
Wireless control of communication using the physical channel for packet is performed.

The operation of the mobile station configured as described above will be described below. When the power is turned on, the standby channel selection control unit 1 is executed after the perch channel scan control unit 101 is executed.
02, and transits to the in-service waiting state. When the zone transition is performed by the zone waiting state control unit 103, the perch channel is notified from the network, and the standby channel selection control unit 102 is activated for the channel having the highest reception level.

When the communication is completed by the voice communication control unit 104, a perch channel for transitioning to the in-service waiting state is notified from the network during communication. Selection control unit 1
02 is started. Similarly, when the communication is terminated by the packet communication control unit 105, the perch channel for transitioning to the in-service standby state is notified, and the standby channel selection control unit 102 is activated for the perch channel. Is done.

[0017]

However, the above-mentioned conventional system has the following problems. The first is a perch channel scan control unit 101
In this case, when the reception level is detected, the reception level is temporarily detected to be high for reasons such as radio wave interference. After that, there is a case where the reception level is low at the time of actually executing the standby channel selection processing, so that there is a high possibility that the standby channel selection processing will fail.

The second is a case where the communication is terminated in the voice communication or the packet communication due to a communication abnormality or a low reception level. There is a case where the perch channel specified from the network cannot be used at the time of executing the standby channel selection processing after the communication ends, so that there is a high possibility that the standby channel selection processing will fail.

As described above, as shown in the above two cases, when the standby channel selection processing is successful, the time required for one wave of the perch channel is generally less than 1 second, whereas the standby channel selection processing is performed. Fails, the time per wave of the perch channel is 1 to
Since the time is about 10 seconds, there is a problem that it takes a long time to shift to the standby state within the service area.

For example, referring to the conceptual diagram of FIG. 9, when voice communication starts at point A, moves to point B while voice communication is in progress, and ends voice communication at point B, it is designated from the network. A standby channel selection process is performed on the perch channel 100 in the service area. At this time, the base station B is already approaching, and the standby channel selection processing of 100 fails, and the processing shifts to perch channel scanning processing.

Thereafter, a standby channel selection process is performed again on the perch channel 400 having a high reception level, and there is a high possibility of success for the first time. Assuming that the time per wave of the perch channel at the time of failure is 10 seconds and the time per wave of the perch channel at the time of success is 1 second, 1
This will take one second.

More specifically, in the above-described perch channel scanning process, the perch channels 200 and 6
The reception level of 00 is actually a reception level at which the standby channel selection process fails, but if it is detected temporarily high, 20 seconds are added and 31 seconds are required. Therefore, depending on the situation, there is a high possibility that the standby channel selection process will fail. If the process fails, there is a problem that it takes time to shift to the in-service standby state.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and reduces the time required for a failure in a standby channel selection process by increasing the success rate of a standby channel selection process, thereby enabling a transition to an in-service standby state. It is an object of the present invention to provide a standby transition time shortening system capable of shortening the time until the standby time.

[0024]

FIG. 1 is a block diagram showing the principle of the present invention. In the figure, reference numeral 1 denotes a mobile station, which performs wireless communication with a base station. In the mobile station 1, reference numeral 11 denotes a perch channel usage rate storage means provided in the mobile station in which the usage rate of the perch channel is stored. Reference numeral 12 denotes a perch channel having a high usage rate from the perch channel usage rate storage means 11. It is characterized by comprising a perch channel selecting means for selecting preferentially.

With such a configuration, the perch channel selection means 12 uses the perch channel having a high usage rate from the perch channel usage rate storage means 11 to eliminate the failure of the channel selection process, and until the transition to the area standby state. Can be shortened.

(2) In a system for performing wireless communication between a mobile station and a base station, the invention according to claim 2 is characterized in that when the mobile station performs a standby channel selection operation at the end of communication,
The present invention is characterized in that the reception levels of the perch channels of the visited zone and the peripheral zone stored in the storage unit in the mobile station in advance are measured, and a zone having a higher reception level is preferentially selected.

With this configuration, since the zone having the higher reception level is preferentially selected, the time required for the failure of the standby channel selection processing can be reduced, and the time until the in-area standby time can be reduced. .

[0028]

Embodiments of the present invention will be described below in detail with reference to the drawings. 1 and 10 are denoted by the same reference numerals. In the figure, hatched portions indicate control and storage areas newly added to the control of the related art, and hatched portions indicate control for adding and modifying the control of the related art. In the figure, a PDC software radio control unit 100 maintains a radio state in a mobile station. Also, the PDC control memory 300 is
C is a memory area in which the software defined radio controller 100 performs processing. Reference numeral 200 denotes a level measuring device for measuring a reception level of a radio wave.

Perch channel scan control unit 101
Is a control unit added so as to activate the statistical information control unit 510 after the perch channel scan processing similar to the conventional technique. The perch channel storage area 301 is an area in which perch channel information measured by the perch channel scan control unit 101 is stored, and the perch channel table 302 detected in order of detection level is detected by the perch channel scan control unit 101. It is a table in which perch channels are associated with reception levels and sorted in descending order of reception level.

The statistical information control unit 510 stores a usage frequency statistical information storage area 512 which is a past perch channel usage rate.
Based on the information, the level detected in the perch channel scan, preferentially select the past high perch channel usage rate, when performing the standby channel selection process,
The control unit has a function of rewriting the detection level sequential perch channel table 302 and a function of executing a standby channel selection process.

The standby channel selection control unit 102 is a control unit that performs a standby channel selection process similar to the prior art. The in-range standby state control unit 103 has a function of storing the usage rate of the currently used perch channel in the usage frequency statistical information storage area 512 in addition to the processing in the in-range standby state as in the related art. It is.
The usage frequency statistical information storage area 512 is an area for storing the usage frequency information of the perch channel calculated by the in-area standby control unit 103.

FIG. 3 is a block diagram showing a second embodiment of the present invention. The same components as those in FIG. 2 are denoted by the same reference numerals. In the figure, the in-range waiting state control unit 10
No. 3 has a function of storing, in addition to the processing in the area waiting state similar to the related art, the perimeter channel information on the periphery and the currently opened perch channel information in the located / peripheral perch channel storage area 502. The control unit has a control unit added to execute the standby channel selection activation determination unit 500 when the process shifts to the standby channel selection process similar to the related art.

Stored / peripheral perch channel storage area 50
Reference numeral 2 denotes an area for storing perch channel information written by the in-zone standby state control unit 103, the voice communication control unit 104, and the packet communication control unit 105.

The voice communication control unit 104 has a function of storing, in addition to the existing processing at the time of voice communication, perimeter perch channel information notified from the network in the located / peripheral perch channel storage area 502. It is a control unit that has been added to execute the standby channel selection activation determination unit 500 when the process shifts to the existing standby channel selection process.

The in-packet communication control unit 105 has a function of storing peripheral perch channel information notified from the network in the located / peripheral perch channel storage area 502 in addition to the existing packet communication processing. However, the control unit is added to execute the standby channel selection activation determination unit 500 when shifting to the existing standby channel selection.

Standby channel selection / activation judging section 500
Detects, using the level detector 200, the reception levels of the perch channel recorded in the located / peripheral perch channel storage area 502 and the perch channel notified from the network for transition to the waiting state. If a level higher than the available level exists for the channel with the higher reception level, the standby channel selection control unit 102 is activated, and if no level higher than the available level exists, the perch channel scan control unit 101 Is a control unit that has a function of selecting to start up.

Perch channel scan controller 101
Is a control unit that performs the same perch channel scan processing as in the prior art. Standby channel selection control unit 10
A control unit 2 performs a standby channel selection process similar to the related art.

In the embodiment shown in FIGS. 2 and 3, when the control is shifted from the execution of the perch channel scan control unit 101 to the execution of the standby channel selection control unit 102, the statistical information control unit 510 is executed. Since a perch channel having a success record of the standby channel selection processing in the past is preferentially selected and operated to execute the standby channel selection processing, a perch whose temporarily high level is detected due to interference or the like is temporarily detected. Since the priority of the channel can be lowered, the success rate of the standby channel selection processing can be increased (FIG. 2).

When the in-service standby state control unit 103, the voice communication control unit 104, and the packet communication control unit 105 execute the standby channel selection control unit 102, the control is transferred to the standby channel selection control unit 102. At this time, the standby channel selection / activation determination unit 500 is executed, and if there is a usable level, the standby channel selection control unit 102 is executed with the highest level of the perch channel, and there is no usable level. In this case, the perch channel scan control unit 101 is operated to execute, so that the execution of the standby channel selection process for the perch channel of the unusable reception level is suppressed, and all the detection levels are unusable. In such a case, operate so as not to execute the standby channel selection processing itself. It can be (Figure 3).

As described above, it is possible to reduce the influence of the failure of the standby channel selection process before the transition to the coverage area standby state, and to shorten the transition time to the coverage area standby state.

FIG. 4 is a first operation explanatory diagram of the embodiment of the present invention, and corresponds to the configuration of FIG. The shaded portions in the figure are control and storage areas added according to the present invention. FIG. 4 shows an embodiment of a method for selecting a perch channel when selecting a standby channel according to the usage rate of a perch channel.

In the figure, the perch channel scan control unit 101 refers to the perch channel storage area 301, acquires the perch channel number and the corresponding frequency code, and sets the reception level of the frequency corresponding to the frequency code to the level. The detection is performed using the measuring device 200, the detection result is sorted in the order of the reception level, and the result is written into the perch channel storage area 302 in the order of the detection level, and the statistical information control unit 510 is started.

The activated statistical information control unit 510 sets the reception level corresponding to the perch channel of the perch channel table 302 of the detection level order to (1 + the usage rate of the same perch channel number in the usage frequency statistical information storage area 512). , And writes the value in the detection level sequential perch channel table 302. This process is performed for all the perch channels in the detection level order perch channel table 302, the detection level order perch channel table 302 is rewritten in the order of the changed reception level, and the standby channel selection control unit 102 is started.

The activated standby channel selection control unit 1
02, the detection level sequential perch channel storage area 30
2, a perch channel is established in order from the perch channel having the highest reception level, the broadcast information is received from the network, and when the processing is successful, the in-zone standby state control unit 1
03, and transits to the in-service waiting state. If the establishment of all the perch channels fails, the perch channel scan control unit 101 is executed, and the process transitions to the perch channel scan process.

FIG. 5 is a second operation explanatory diagram of the embodiment of the present invention, and corresponds to the configuration of FIG. When the in-range standby state control unit 103 cannot maintain the in-range standby state, when transitioning to voice communication, and when transitioning to packet communication, the perch channel used in the past with respect to the in-range standby time accumulated value is used in the past. The time and the ratio of the total time of the time used this time are calculated, and the calculation result is written to the usage frequency statistical information storage area 512.

Therefore, the statistical information control unit 510 converts the perch channel numbers “38, 1,...” And the reception levels “31, 30” of the permutation level perch channel table 302 generated by the perch channel scan control unit 101.
... ”, the reception level is“ 31 × (1 + 0.04), 3
0 × (1 + 0.10)... ”, The contents of the detection level sequential perch channel table 302 are changed to perch channel numbers“ 1, 38... ”And reception levels“ 33, 32. The order is changed.

Since the standby channel selection process is started in the order of the reception level in the detection level sequential perch channel table 302, the first perch channel to be started is the perch channel number 1, which is the past level in addition to the current level. Is executed with priority given to the perch channel taking into account the perch channel with a high track record of use.

According to the above-described embodiment, the perch channel selection means 12 uses the perch channel having a high usage rate from the perch channel usage rate storage means 11 to eliminate the failure of the channel selection processing and to wait in the service area. The time required for the state transition can be reduced.

FIG. 6 is a third operation explanatory diagram of the embodiment of the present invention, and corresponds to the configuration of FIG. This figure shows an example of an embodiment in which information is set in the located / peripheral perch channel storage area 502.

When the in-range waiting state control unit 103 is running, the broadcast information is transmitted. When the voice communication control unit 104 is running, the radio status report information / system information is transmitted. When the packet communication control unit 105 is running, the broadcast information is broadcast. Upon receiving a signal from the network in the / zone information notification, the present and nearby perch channel information existing in the signal is set in the present / peripheral perch channel storage area 502. Then, when it becomes impossible to maintain the reception level enough to maintain the standby state (hereinafter referred to as standby maintenance impossibility), when the voice communication or the packet communication ends, the standby channel selection / activation determining unit 500 is executed.

FIG. 7 is a fourth operation explanatory view of the embodiment of the present invention, and corresponds to the configuration of FIG. The same components as those in FIG. 3 are denoted by the same reference numerals. Each of the standby channel selection and activation determination units 500 executed by the in-range standby state control unit 103, the voice communication control unit 104, and the packet communication control unit 105 determines whether the in-service / peripheral perch channel storage area 502 is in the service / stop. The reception level is measured with reference to the tree channel information, and if the maximum level of the detected levels is equal to or lower than the standby permission level (the minimum level for entering the area standby state), the perch channel scanning process is started, and so on. If not, the standby channel selection control unit 102 is activated by the perch channel having the maximum level among the detected levels.

Therefore, the in-range standby state control unit 103,
Voice communication control unit 104 or packet communication control unit 1
The received perch channel received from the network at 05 is "8
2 "and the surrounding perch channels are" 12, 105 ... "
If it is, the area / perimeter perch channel storage area 5
02 is set to “82, 12, 105...”, The standby channel selection control unit 102 measures the reception level of the perch channel in the serving / peripheral perch channel storage area 502 and determines the perch channel “82, 12,. , 105 ... "
Are detected as “−1, 16, 26...”, The perch channel having the highest reception level is the perch channel number 105, and the standby channel selection control unit 102
Is activated by the perch channel of the perch channel number 105 of the maximum reception level.

In the prior art, when the reception level measured by the perch channel scan control section 101 is temporarily detected to be a high level due to interference or the like, or when standby cannot be maintained / voice communication ends / packet communication ends. If the perch channel specified at the time is not a sufficient reception level, in order to perform a standby channel selection process for a perch channel that is not a sufficient reception level, if the probability of processing failure is high, if It takes a lot of time to shift to the standby state again.

According to this embodiment, when a high level is temporarily detected by the perch channel scan control section 101, a perch channel which has been used in the past is preferentially selected. It operates to start the standby channel selection processing, and operates to start the standby channel selection processing using a perch channel with a sufficient reception level when standby cannot be maintained / when voice communication ends / packet communication ends. Therefore, there is a high probability that the standby channel selection process will succeed immediately.

For example, referring to the conceptual diagram of FIG. 9 and an example of a standby transition time shortening process (details will be described later) of FIG.
0, without immediately performing the standby channel selection process.
After measuring the reception level of the serving perch channel 100 and the surrounding perch channels 300, 400, 500,
When the standby channel selection process is performed at 400 having a high reception level, there is a high probability that the standby channel selection process immediately succeeds. In the prior art, the standby transition time that required 11 seconds or 31 seconds was completed in 1 second, and 10 seconds or 30 seconds.
Seconds can be reduced.

FIG. 8 is an explanatory diagram of the process of shortening the standby transition time according to the present invention. First, voice communication is started at point A (S1). Next, a system information message is received from the located 100 ch (S2). The received channel is stored in the visited / perimeter perch channel storage area 502 (S3).

Next, the mobile station receives the radio status report information message (S4), and stores the channel ch of the received message in the visited / perimeter perch channel storage area 502 (S5). Next, the mobile station ends the voice call at the point B (S6). Next, referring to the visited / peripheral perch channel storage area 502, the level measurement of the visited / peripheral perch channel is started (S7). As a result, the level measurement is completed (S8). The completed levels are 8 dB for 100 ch, 5 dB for 200 ch, 12 dB for 300 ch,
20ch for 400ch, 10dB for 500ch, 600
It is assumed that ch is 3 dB. The mobile station performs a standby channel selection process on the 400ch with the highest reception sensitivity (S9).

According to this embodiment, a zone having a high reception level is preferentially selected, so that the time required for the failure of the standby channel selection processing is reduced, and the time until the in-area standby time is reduced. Can be.

The following can be considered as another embodiment of the present invention. Usage frequency statistical information storage area 51
In 2, the ratio of the waiting time of the perch channel is used as the usage rate, but the operation may be performed based on other information such as the ratio of the number of times the perch channel is used.

In the statistical information control section 510, the reception level is corrected by (1 + use rate), but may be corrected by using another calculation method such as an average deviation. The standby channel selection / activation determination unit 500 may identify a plurality of channels with high reception levels and sequentially activate the standby channel selection control unit 102 for them.

In standby channel selection / activation determining section 500, the level measurement for the same channel may be performed a plurality of times to improve the measurement accuracy. Also, the present invention relates to PD
The present invention is not limited to the C system, and can be similarly applied to other wireless communication systems.

[0062]

As described above, according to the present invention, the following effects can be obtained. (1) According to the first aspect of the present invention, the perch channel usage rate storage means provided in the mobile station unit in which the usage rate of the perch channel is stored, and the perch channel usage rate storage means stops at a high usage rate. By providing the perch channel selecting means for preferentially selecting the perch channel, the perch channel selecting means can use the high perch channel from the perch channel usage rate storing means to prevent the channel selection process from failing. Thus, it is possible to shorten the time required for shifting to the waiting state within the service area.

(2) According to the second aspect of the invention, when the mobile station performs a standby channel selection operation at the end of communication,
By measuring the reception level of the perch channel of the visited zone and the peripheral zone stored in advance in the internal storage unit of each mobile station, and prioritizing and selecting the zone having the higher reception level, the zone having the higher reception level is prioritized. Therefore, the time required for the failure of the standby channel selection processing can be reduced, and the time until the in-area standby time can be reduced.

As described above, according to the present invention, by increasing the success rate of the standby channel selection processing, the time required for the failure of the standby channel selection processing can be reduced, and the time required for transition to the in-service standby state can be reduced. A system for shortening a standby transition time can be provided.

[Brief description of the drawings]

FIG. 1 is a principle block diagram of the invention according to claim 1;

FIG. 2 is a block diagram illustrating a first embodiment of the present invention.

FIG. 3 is a block diagram showing a second embodiment of the present invention.

FIG. 4 is a first operation explanatory diagram of the embodiment of the present invention.

FIG. 5 is a second operation explanatory diagram of the embodiment of the present invention.

FIG. 6 is a third operation explanatory diagram of the embodiment of the present invention.

FIG. 7 is a diagram illustrating a fourth operation according to the embodiment of the present invention.

FIG. 8 is an explanatory diagram of a process of reducing a standby transition time according to the present invention.

FIG. 9 is a conceptual diagram of wireless channel switching in the PDC system.

FIG. 10 is a functional configuration diagram of a conventional PDC wireless control unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Mobile station 11 Perch channel utilization storage means 12 Perch channel selection means

Continued on the front page (72) Inventor Yuki Saito 1-1-5 Shimonopporo Techno Park, Atsetsu-ku, Sapporo, Hokkaido Fujitsu Hokkaido Communication Systems Co., Ltd. (72) Masato Hayasaka 1-1-5 Shimonopporo Techno Park, Atsubetsu-ku, Sapporo, Hokkaido Fujitsu Hokkaido Communication Systems Co., Ltd. (72) Inventor Hiroshi Karasawa 1-5-1, Shimonopporo Techno Park, Atsubetsu-ku, Sapporo, Hokkaido Fujitsu Hokkaido Communication Systems Co., Ltd. (72) Hideyuki Akiba 1-1-1, Shimonopporo Techno Park, Atsubetsu-ku, Sapporo, Hokkaido No. 5 Fujitsu Hokkaido Communication System Co., Ltd. F term (reference) 5K067 AA14 BB04 CC04 EE02 EE10 GG06 JJ03 JJ13 JJ19 KK15

Claims (2)

[Claims] In a system for performing wireless communication between a mobile station and a base station, a perch channel usage rate storage means provided in a mobile station for storing a perch channel usage rate, and the perch channel usage rate storage. A standby travel time reduction system comprising a perch channel selecting means for preferentially selecting a perch channel having a high use rate from the means. 2. A system for performing wireless communication between a mobile station and a base station, wherein when the mobile station performs a standby channel selection operation at the end of communication, a visited zone and a peripheral zone stored in a storage unit in the mobile station in advance. A reception level of a perch channel of the mobile station is measured, and a zone having a high reception level is preferentially selected.