JP2003219480A - Mobile communication apparatus and display control method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a mobile communication apparatus capable of adequately displaying a communication enable/disable state. <P>SOLUTION: During the packet communication, a CPU 5 controls a radio unit 2 to perform a perch scan for retrieving a perch channel of a communicable level. It decides whether the retrieved channel adapts to the packet communication. If adapting to the packet communication, the CPU 5 selects the retrieved channel as a new packet channel. But, if not adapting to the packet communication, it sets a skip mode on a selection table generated in a RAM 4 and continues retrieving other channels. If the skip mode is set on the selection table in the RAM 4 whereas no channel is ensured after ending the perch scan, the CPU 5 indicates a symbol showing own location being inside a communication area on a display 6, not indicating own location being out of the communication area. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a mobile communication device and a display control method.

[0002]

2. Description of the Related Art In recent years, with the progress of mobile communication systems, mobile communication devices such as mobile phones have become widespread.
In such a mobile communication system, a plurality of base stations are installed in a distributed manner, and the mobile communication device communicates with other mobile communication devices, etc. via a nearby base station (base station within communication range). Communicate between.

A mobile communication device executes a process called "perch scan" when the power is turned on or when it is outside the communication range. This perch scan measures the reception level of all channels that are candidates for the perch channel, searches for a channel that enables stable communication, and then attempts to synchronize with the control channel to wait It is the process of moving to. Then, if a channel at the communicable level cannot be searched at all, or if the control channel cannot be synchronized even if it can be searched, the mobile communication device waits for a predetermined time and then performs a perch scan again. To do. In this way, while repeating perch scanning, it becomes impossible to make and receive calls,
In order to inform the user, the mobile communication device
For example, the symbol "out of service" is displayed on the display unit. That is, the mobile communication device displays the out-of-range display while the perch channel cannot be secured.

Recently, mobile communication devices that can send and receive e-mails and access the Internet as well as making telephone calls have become widespread. Such a mobile communication device can perform data transmission with a predetermined service provider or the like via a base station by packet communication, and can display useful received information on a display unit.

[0005]

In the mobile communication system described above, there is a zone in which only voice transmission / reception can be performed (non-packet support zone) and a zone in which packet communication is also possible (packet support zone). ing. That is, base stations that cannot perform packet communication and base stations that can perform packet communication are arranged in a distributed manner.
Therefore, during packet communication in the packet support zone, a user carrying a mobile communication device may move to the non-packet support zone. In such a case, there is a problem that the mobile communication device displays the out-of-range display although the mobile communication device can make and receive a voice call.

[0006] For example, as shown in FIG. 7, in a situation where a zone A, which is a packet support zone, and a zone B, which is a non-packet support zone, are adjacent to each other, a user carrying a mobile communication device is X1. It is assumed that the point has been sequentially moved to the point X4. In this case, before reaching point X2,
A symbol s1 indicating the communication range (radio wave reception level) is displayed on the display unit of the mobile communication device during packet communication. Nevertheless, after crossing the point X2, the mobile communication device repeatedly searches for a base station (base station capable of packet communication) by a perch scan, so that the display section displays the symbol s3 indicating the out-of-coverage area. The Rukoto. When the packet communication ends due to a timeout or the like before reaching the point X3, a perch scan is searched for a base station that can make and receive a voice call. After that, when synchronization with the control channel that can be searched for is completed at the point X3, the symbol s1 indicating the communication area is displayed again on the display unit of the mobile communication device.

In addition to this, even when the wireless quality for packet communication deteriorates while staying in the packet support zone, the mobile communication device similarly stops the base station (base station capable of packet communication). Since the tree scan is repeatedly searched, the symbol indicating the outside of the communication area is displayed on the display unit during that time.

When the mobile communication device displays the symbol indicating the out-of-communication range (out-of-service display) in a situation where voice calls can be made and received as described above, unnecessary misunderstanding or confusion is given to the user. Will be given. For example, a user may misunderstand that the mobile communication device may have failed, or may mistakenly consider that the service area of the mobile communication system is inadequate, and the user may trust the mobile communication device or the mobile communication system. You will lose your sense.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a mobile communication device and a display control method capable of appropriately displaying the communication enabled / disabled state.

[0010]

In order to achieve the above object, a mobile communication device according to a first aspect of the present invention is applied to a mobile communication system adopting a cell system, and a base station in the vicinity of the mobile communication device is used. A mobile communication device for performing packet communication and voice communication via a packet communication device, wherein scanning means for searching a perch channel according to predetermined channel information and base station of the perch channel searched by the scanning means are packet communication. And at least during packet communication, if the base station of the perch channel is determined not to support packet communication, at least during packet communication, information indicating out-of-communication range And a display unit that displays information indicating the communication area without displaying.

To achieve the above object, a mobile communication device according to a second aspect of the present invention is applied to a mobile communication system adopting a cell system, and packet communication and voice are transmitted via a base station in the vicinity. A mobile communication device that makes a call, performs scanning of a perch according to a predetermined frequency table, and a scanning unit that searches for a perch channel of a predetermined reception level, and a base station of the channel searched by the scanning unit is a packet. At least during packet communication according to the determination means for determining whether or not communication is supported, the storage means for storing the determination information defining the determination result determined by the determination means, and the determination information stored in the storage means. Display means for displaying information indicating a communicable / non-communicable state.

[0012] The display means displays the out-of-communication area at least when the storage means stores the discrimination information indicating that the searched base station of the perch channel does not support the packet communication at least during the packet communication. The information indicating the communication area may be displayed without displaying the information.

To achieve the above object, a mobile communication device according to a third aspect of the present invention is applied to a mobile communication system adopting a cell system, and packet communication and voice are transmitted via a base station in the vicinity. A mobile communication device that makes a call, at least during packet communication, searches for a perch channel according to predetermined channel information,
When it is determined that the searched perch channel base station does not support packet communication, the information indicating the out-of-communication area is displayed on a predetermined display unit without displaying the information indicating the out-of-communication area. And

To achieve the above object, a mobile communication device according to a fourth aspect of the present invention is applied to a mobile communication system adopting a cell system, and packet communication and voice are transmitted via a base station in the vicinity. A mobile communication device that makes a call, performs a perch scan according to a predetermined frequency table, searches for a perch channel with a predetermined reception level, and determines whether the base station of the searched channel supports packet communication. It is determined that the determination result is stored in a predetermined storage unit, and the determination information that defines the determination result is stored in a predetermined storage unit. At least during packet communication, the determination information stored in the storage unit is information that does not support packet communication. In this case, the information indicating the out-of-communication area is displayed on a predetermined display unit without displaying the information indicating the out-of-communication area.

In order to achieve the above object, the display control method according to the fifth aspect of the present invention is applied to a mobile communication system adopting a cell system, and packet communication and voice communication are performed via a base station in the vicinity. A method of controlling display in a mobile communication device for performing, in accordance with predetermined channel information, a scanning step of searching for a perch channel, and a base station of the perch channel searched in the scanning step for packet communication. A determination step of determining whether or not it is compatible, and at least during packet communication, when it is determined that the base station of the perch channel is not compatible with packet communication in the determination step,
A display step of displaying the information indicating the coverage area on a predetermined display unit without displaying the information indicating the coverage area.

In order to achieve the above object, a display control method according to a sixth aspect of the present invention is applied to a mobile communication system adopting a cell system, and packet communication and voice communication are performed via a base station in the vicinity. A display control method in a mobile communication device for performing a perch scan according to a predetermined frequency table, a scan step of searching for a perch channel of a predetermined reception level, and a channel searched in the scan step. A determination step of determining whether or not the base station of the present invention is compatible with packet communication, and a storage step of storing determination information defining a determination result determined in the determination step in a predetermined storage unit,
A display step of displaying at least information indicating a communicable / uncommunicable state during packet communication on a predetermined display section according to the discrimination information stored in the storage section in the storing step.

The display step indicates that the communication area is out of the communication area when the storage unit stores the discrimination information indicating that the searched base station of the perch channel does not support the packet communication at least during the packet communication. The information indicating the communication area may be displayed on the display unit without displaying the information.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION A mobile communication device according to an embodiment of the present invention will be described below with reference to the drawings. It should be noted that this mobile communication device is used in a mobile communication system adopting a cell system.

FIG. 1 is a block diagram showing an example of a mobile communication device applied to the embodiment of the present invention. As shown, this mobile communication device includes an antenna 1, a wireless unit 2, a ROM 3, a RAM 4, a CPU 5, a display unit 6, a key operation unit 7, a speaker 8, and a microphone 9. Composed of. This mobile communication device is capable of data transmission by packet communication in addition to normal voice communication.

The antenna 1 is composed of a predetermined rod antenna or the like having an element, superimposes the communication information supplied from the radio section 2 on a carrier wave of a predetermined frequency, and transmits it to a nearby base station or the like. The antenna 1 also receives communication information (radio waves) sent from a nearby base station or the like, and supplies it to the wireless unit 2.

The radio unit 2 is controlled by the CPU 5 and transmits predetermined communication information (voice information, voice information, etc.) to a nearby base station (finally, another mobile phone, a service provider, etc.) via the antenna 1. Send and receive communication packets, etc.). The radio unit 2 also measures the electric field strength (RSSI) of each channel (a plurality of channels that are candidates for a perch channel) that are present in the vicinity and received via the antenna 1.

A ROM (Read Only Memory) 3 stores in advance programs that define packet communication processing, perch scanning processing, out-of-service display control processing, rescan processing, etc., which will be described later. The ROM 3 also stores in advance a frequency table and the like that defines the frequencies and the like of multiple channels that are candidates for perch channels.

A RAM (Random Access Memory) 4 is a C
The PU 5 stores work information, variables, and the like necessary when executing packet communication processing, perch scan processing, and the like, which will be described later. For example, the RAM 4 stores a selection table or the like for selecting a handover candidate or the like according to the electric field strength of each channel measured by the wireless unit 2. In addition, RAM4
Stores the electric field strength value and the like measured for the channel currently used by the mobile communication device. The selection table, the electric field strength value, and the like are updated by the CPU 5 at predetermined timings. The RAM 4 also stores the number of times perch scanning has been performed.

CPU (Central Processing Unit) 5
Executes a program stored in the ROM 3 (packet communication processing, perch scanning processing, etc., which will be described later), and controls the entire mobile communication device. Specifically, the CPU 5 controls the wireless unit 2 to perform a perch scan or the like, generate a selection table for selecting a handover candidate or the like, and generate the RAM 4
To memorize. At that time, the selection table is generated while determining whether or not the packet communication is possible. Then, according to the generated selection table and the like, the CPU 5 displays the symbol indicating the communication enabled / disabled state on the display unit 6.

The display unit 6 is composed of a liquid crystal display panel or the like,
Various information for notifying the user of the operation status of the mobile communication device is displayed. For example, the display unit 6 displays information such as date / time, information indicating the remaining amount of the battery, communication range (reception level of the channel currently used), information indicating outside the communication range, and the like.

The key operation unit 7 is composed of a plurality of operation keys arranged on the front surface (front surface) of the device or the like. For example, the operation unit 7 includes numeric keys, character keys, function keys, and
It includes a call key, etc.

The speaker 8 emits a voice or the like in accordance with a voice signal or the like demodulated by a base band unit (not shown) or the like. The microphone 9 is composed of a condenser microphone or the like, converts the collected voice of the user into a voice signal, and supplies the voice signal to a baseband unit or the like (not shown).

The operation of the mobile communication device according to the embodiment of the present invention will be described below with reference to FIGS. 2 is a flow chart for explaining the packet communication process, FIG. 3 is a flow chart for explaining the perch scan process, and FIG. 4 is a flow chart for explaining the out-of-service display control process. Then, FIG. 5 is a flowchart for explaining the rescan processing. It should be noted that these processes are executed by appropriately reading the program stored in the ROM 3 by the CPU 5.

First, the packet communication process will be described with reference to FIG. It is assumed that the mobile communication device has started packet communication with a service provider or the like in a predetermined packet support zone.

First, the CPU 5 transmits / receives a predetermined packet via the radio unit 2 or the like (step S11). That is, the CPU 5 transmits / receives a packet via a base station in the vicinity on the currently used channel.

The CPU 5 obtains the quality measurement result by interrupt processing (step S12). For example, CPU5
Gets the field strength (RSSI) value measured for the channel currently in use.

The CPU 5 determines whether or not the level of the currently used channel has deteriorated (step S1).
3). For example, the CPU 5 determines whether the level has deteriorated by comparing the acquired electric field strength value with a predetermined reference value.

When the CPU 5 determines that the level of the currently used channel has not deteriorated, the CPU 5 advances the process to step S15 described later. On the other hand, when it is determined that the level has deteriorated, the CPU 5 executes the perch scanning process (step S14). That is, the CPU 5
According to the frequency table stored in the OM3, the reception level is measured for each perch channel, and channels above a certain level are secured. The details of the perch scanning process will be described later.

The CPU 5 determines whether or not the packet communication is completed (step S15). For example, CPU5
Determines whether or not the user has instructed to end the packet communication via the key operation unit 7.

When it is determined that the packet communication is not completed, the CPU 5 returns the process to step S11 and repeatedly executes the processes of steps S11 to S15 described above. On the other hand, when it is determined that the packet communication is completed,
The CPU 5 ends the packet communication process.

Next, the perch scanning process performed in step S14 will be described with reference to FIG. First, the CPU 5 controls the wireless unit 2 to perform a perch scan (step S21). That is, the CPU 5
Adjusts frequencies to a plurality of channels according to a frequency table stored in advance in the ROM 3 and measures the electric field strength value of each channel. Then, a selection table for selecting handover candidates and the like is generated and stored in the RAM 4.

The CPU 5 sets no skip for all channels in the selection table stored in the RAM 4 (step S22). That is, the CPU 5 clears the skip information in the selection table.

The CPU 5 updates the number of scans stored in the RAM 4 (step S23). That is, the CPU
The value 5 is updated by adding 1 to the value for managing the number of perch scans.

The CPU 5 searches the perch scan performed in step S21 for a channel having a reception level capable of stable communication, and determines whether or not the searched channel has a selectable control channel (step S21). Step S24). That is, the CPU 5 determines whether or not there is a controllable channel that is a communicable level channel.

When the CPU 5 determines that there is a selectable control channel, it determines whether the packet service is available (step S25). That is, CP
The U5 determines from the information obtained from the control channel whether or not the packet service is available at the base station.

When the CPU 5 determines that the packet service is not available (only voice transmission / reception is available), the CPU 5 sets skip in the corresponding channel of the selection table (step S26). Then, the CPU 5 returns the process to step S24 described above.

On the other hand, when it is determined that the packet service is available, the CPU 5 selects the searched channel as a new packet channel (step S2).
7). Then, after selecting the packet channel, the process is returned to the packet communication process shown in FIG.

If it is determined in step S24 that there is no selectable control channel, the CPU 5
Performs out-of-service display control processing (step S28). The details of the out-of-service display control process will be described later.

The CPU 5 sets the next scan timing (step S29). For example, the CPU 5 sets, in a timer circuit (not shown), the remaining time until the next perch scan is started. Then, after setting the scan timing, the CPU 5 returns the process to the packet communication process shown in FIG.

Next, regarding the out-of-service display control process performed in step S28 of the perch scanning process described above,
This will be described in detail with reference to FIG. First, the CPU 5 determines whether the set value of the option switch is "A",
It is determined whether it is "B" (step S31).
The option switch is a set value for selecting out-of-service display control during packet communication or out-of-service display control when the number of perch scans exceeds a specified value. The setting value of this option switch is arbitrarily set by the user. With this option switch, the out-of-service area display control during packet communication can be made even more desired by the user.

When the CPU 5 determines that the setting value of the option switch is "A", it determines whether packet communication is in progress (step S32).

When it is determined that the packet communication is not being performed (when the perch channel is not secured during the voice communication), the CPU 5 advances the processing to step S35 described later. On the other hand, when it is determined that packet communication is in progress, the CPU 5 determines whether or not there is a skip setting in the selection table stored in the RAM 4 (step S33). That is, the CPU 5 determines whether or not there is a channel through which voice can be transmitted / received during packet communication.

When the CPU 5 determines that the setting with skip is present, for example, the symbol of 0 antennas (the symbol representing only the antenna) is generated and the display unit 6 is operated.
(Step S34). That is, the CPU 5
Displays the symbol indicating the coverage area on the display unit 6 without displaying the symbol indicating the coverage area. In addition, instead of displaying the symbol of 0 antennas on the display unit 6,
The symbol indicating the current reception level (the symbol indicating the antenna and the vertical bar) may be continuously displayed as it is.

When the CPU 5 displays the symbols of 0 antennas on the display unit 6, the CPU 5 finishes the out-of-range display control process and returns the process to the perch scanning process shown in FIG.

On the other hand, if it is determined that there is no skip setting in the selection table (including the case where it is determined that packet communication is not in progress in step S32), the CPU
5 displays a symbol indicating the outside of the communication range on the display unit 6 (step S35). Then, the out-of-service display control process is completed, and the process is returned to the perch scanning process in FIG. 3 described above.

When it is determined in step S31 that the value of the option switch is "B", it is determined whether packet communication is in progress (step S36). C
If the PU 5 determines that packet communication is not in progress (when a perch channel is not secured during voice communication), the process proceeds to step S39 described below. On the other hand, if it is determined that packet communication is in progress, the CPU 5
Determines whether or not there is a skip setting in the selection table stored in the RAM 4 (step S37).

When the CPU 5 determines that there is no skip setting in the selection table, the process proceeds to step S39 described later. On the other hand, if it is determined that there is a setting with skip in the selection table, the CPU 5
Determines whether the number of scans stored in the RAM 4 (the number of perch scans) is larger than the specified value N (step S38). When the CPU 5 determines that the number of scans is not larger than the specified value N (is equal to or smaller than the specified value N), the CPU 5 advances the process to step S34 described above, and displays the symbols of 0 antennas on the display unit 6 without displaying the out-of-range. indicate. On the other hand, when it is determined that the number of scans is larger than the specified value N (including the case where it is determined that the packet communication is not in progress in step S36 and the setting with skip is not present in step S37), CP
U5 displays the symbol indicating the outside of the communication range on the display unit 6 (step S39). Then, the out-of-service display control process is completed, and the process is returned to the perch scanning process in FIG. 3 described above.

Next, the rescan processing performed after the next scan timing is set in step S29 of the perch scan of FIG. 3 described above will be briefly described with reference to FIG. First, the CPU 5 waits for subsequent processing until the set scan timing arrives (step S41). Then, when the scan timing arrives, the CPU 5 executes a perch scanning process (step S42). That is, the CPU 5 executes the perch scanning process of FIG. 3 and the out-of-service display control process of FIG. 4 described above.

The operation of the mobile communication device according to the above-mentioned processing will be described more specifically below. For example,
As shown in FIG. 6, in a situation where the zone A, which is a packet support zone, and the zone B, which is a non-packet support zone, are adjacent to each other, a user carrying the mobile communication device according to the present embodiment It is assumed that the movement has been made in order from point X1 to point X4. It is assumed that the mobile communication device is in packet communication from the point X1.

In this case, before reaching the point X2, the symbol s1 indicating the service area (radio wave reception level) is displayed on the display unit of the mobile communication device during packet communication. Then, when the point reaches the point X2, in step S13 of the packet communication processing of FIG. 2 described above, the level deterioration of the channel is determined, and the perch scanning processing is executed.

When the perch scanning process shown in FIG. 3 is executed, the existence of a selectable control channel (B zone) is discriminated in step S24, and step S2
At 5 it is determined that the packet service is not available. Therefore, the skip table is set in the selection table of the RAM 4. Subsequently, in step S28, the out-of-service display control process is executed.

When the out-of-service display control process shown in FIG. 4 is executed (assuming that the setting value of the option switch is "A"), it is determined in step S32 that packet communication is in progress, and selected in step S33. It is determined that the table is skipped. Therefore, in step S34, a symbol with zero antennas is displayed.

That is, as shown in FIG. 6, even when the point reaches the point X2, the symbol s2 indicating the communication area is displayed (the symbol indicating the outside of the communication area is not displayed). When the packet communication ends due to a timeout or the like before reaching the point X3, a perch scan is searched for a base station that can make and receive a voice call. After that, when synchronization with the control channel that can be searched for is completed at the point X3, the symbol s1 indicating the communication area is displayed again on the display unit of the mobile communication device.

When the setting value of the above-mentioned option switch is "A", the out-of-service / in-service notification can be performed speedily. That is, it is effective when the user carrying the mobile communication device frequently moves. On the other hand, when the setting value of the above-mentioned option switch is "B", within-range notification is given until the number of perch scans exceeds the specified value N, and when the number of perch scans exceeds the specified value N, an out-of-range notification is given. Will be done. Therefore, when the vehicle is stopped between the points X2 and X3 shown in FIG. 6, the out-of-service notification can be performed more accurately than when the set value is “A”. That is, it is effective when the user carrying the mobile communication device does not move much.

As described above, even if the zone is moved to the non-packet support zone during the packet communication, if the voice call can be made and received, the out-of-range display is not performed. For this reason, unlike the prior art (as shown in FIG. 7), it is not displayed as out-of-service area during packet communication and is not displayed in service area after the packet communication is completed, which does not cause unnecessary misunderstanding or confusion to the user. That is, the user is not misunderstood that the mobile communication device is out of order or the service area of the mobile communication system is insufficient, and the reliability of the mobile communication device or the mobile communication system is not impaired. In addition to this, when the wireless quality for packet communication is deteriorated while staying in the packet support zone, appropriate display can be performed as in the above case. In other words, even if the wireless quality for packet communication deteriorates in the packet support zone, the perch scanning process and out-of-range display control process described above are executed, and if outbound / incoming voice is possible, out-of-range display is performed. Absent. As a result, it is possible to properly display the communication enabled / disabled state.

In the above embodiment, at the time of perch scanning (step S2 in the perch scanning process of FIG. 3).
Although the skip information of the selection table is cleared in 2), the skip information of the selection table may be cleared at another timing when roaming is considered. For example, the skip information in the selection table may be cleared when the scan on the home network and all roaming networks has failed.

In the above embodiment, since it is not preferable to let the user recognize the distinction between the packet support zone and the non-packet support zone, the case where the display is simply divided into the in-range display and the out-of-range display has been described. , May be sorted into other displays. For example, the display of the communication state may be divided into voice communication and packet communication, and voice transmission / reception enabled / disabled and packet communication enabled / disabled may be displayed respectively.

[0063]

As described above, according to the present invention,
It is possible to properly display whether communication is possible or not.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a configuration of a mobile communication device according to an embodiment of the present invention.

FIG. 2 is a flowchart for explaining packet communication processing according to the embodiment of the present invention.

FIG. 3 is a flowchart for explaining a perch scanning process according to the embodiment of the present invention.

FIG. 4 is a flowchart for explaining out-of-service display control processing according to the embodiment of the present invention.

FIG. 5 is a flowchart for explaining rescan processing according to the embodiment of the present invention.

FIG. 6 is a schematic diagram showing an example of symbols displayed on the display unit as the mobile communication device according to the embodiment of the present invention moves.

FIG. 7 is a schematic diagram showing an example of symbols displayed on a display unit along with movement of a conventional mobile communication device.

[Explanation of symbols]

1 antenna 2 radio section 3 ROM 4 RAM 5 CPU 6 Display 7 Key operation part 8 speakers 9 microphone

Claims (8)

[Claims] 1. A mobile communication device which is applied to a mobile communication system adopting a cell system and which performs packet communication and voice communication via a base station in the vicinity, and which stops in accordance with predetermined channel information. A scanning means for searching the tree channel; a judging means for judging whether or not the base station of the perch channel searched by the scanning means supports packet communication; and a perch by the judging means at least during packet communication. When the base station of the channel is determined not to support the packet communication, the mobile device is provided with a display unit for displaying the information indicating the coverage area without displaying the information indicating the coverage area. Body communication equipment. 2. A mobile communication device which is applied to a mobile communication system adopting a cell system and which performs packet communication and voice communication via a nearby base station, and is a perch according to a predetermined frequency table. Scan means for performing a scan to search for a perch channel of a predetermined reception level; discriminating means for discriminating whether or not the base station of the channel retrieved by the scanning means supports packet communication; and the discriminating means for discriminating. Storage means for storing discrimination information defining the discrimination result, and display means for displaying at least information indicating a communicable state / incapable state during packet communication according to the discrimination information stored in the storage means. A characteristic mobile communication device. 3. The display means communicates at least during packet communication, when discrimination information indicating that the searched base station of the perch channel does not support packet communication is stored in the storage means. The mobile communication device according to claim 2, wherein the information indicating the communication area is displayed without displaying the information indicating the out-of-service area. 4. A mobile communication device which is applied to a mobile communication system adopting a cell system and performs packet communication and voice communication via a base station in the vicinity, which is predetermined at least during packet communication. If the perch channel is searched for according to the channel information and it is determined that the base station of the perch channel that is searched does not support packet communication, the information indicating the coverage area is displayed without displaying the information indicating the out-of-coverage area. Is displayed on a predetermined display unit. 5. A mobile communication device which is applied to a mobile communication system adopting a cell system and which performs packet communication and voice communication via a nearby base station, and is a perch according to a predetermined frequency table. Performs a scan to search for a perch channel with a predetermined reception level, determines whether the base station of the searched channel is compatible with packet communication, and stores the determination information that defines the determination result in a predetermined storage unit. However, at least during packet communication, if the discrimination information stored in the storage unit is information indicating that the packet communication is not supported, the information indicating the out-of-coverage area is displayed without displaying the information indicating the out-of-coverage area. A mobile communication device characterized by being displayed on a predetermined display unit. 6. A display control method applied to a mobile communication system adopting a cell system and performing packet communication and voice communication via a base station in the vicinity, which is a predetermined channel. According to the information, a scanning step of searching for a perch channel, a determining step of determining whether or not the base station of the perch channel searched in the scanning step supports packet communication, and at least during packet communication, When it is determined that the base station of the perch channel does not support packet communication in the determination step, the information indicating the out-of-communication area is displayed on the predetermined display unit without displaying the information indicating the out-of-communication area. A display control method comprising: a display step. 7. A display control method applied to a mobile communication system adopting a cell system and performing packet communication and voice communication via a base station in the vicinity, the display control method comprising a predetermined frequency. A scanning step of performing a perch scan according to the table to search for a perch channel of a predetermined reception level; and a determining step of determining whether or not the base station of the channel searched in the scanning step supports packet communication. According to the determination information stored in the storage unit in the storing step, the storage step of storing the determination information defining the determination result in the determination step in a predetermined storage unit, and at least communication during packet communication is possible. A display step of displaying information indicating the impossible state on a predetermined display unit, Display control how. 8. The display step is outside the communication range, at least during packet communication, when discrimination information indicating that the searched base station of the perch channel does not support packet communication is stored in the storage unit. The display control method according to claim 7, wherein the information indicating the communication area is displayed on the display unit without displaying the information indicating the.