JP2000115827A - Communication terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the selection efficiency of a base station used while it is in a standby state or the like. SOLUTION: When acquisition operation for a control channel is conducted, searching is started to receive sequentially control channels (ST1-ST4). A base station related to a control channel, whose received signal strength indicator RSSI is higher than a zone selection level and where a CS-ID inserted thereto is not included in a selection disable data list of a RAM, is used as an object of selection among received control channels an CS data (CS-ID, RSSI or the like) of the selection object are written and stored in the RAM (ST5-ST10). For example, control channels are received in the order of higher reception signal strength to acquire a system information notice, whether or not the base station object can be selected and used in the standby state is discriminated, and a first selection object discriminated to be selectable is used for a base station used in the standby state (ST11-ST17). Since the configuration of eliminating base stations disabled of selection from selection objects is adopted, the selection efficiency of one base station utilized in the standby state is enhanced.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device suitable for use in a portable telephone or the like. More specifically, by selecting a base station that performs wireless communication, based on the identification information of the non-selectable base station stored in the memory means, and excluding the base station that cannot be selected in advance, it is possible to perform standby and the like. The present invention relates to a communication terminal device capable of efficiently selecting one base station to be used.

[0002]

2. Description of the Related Art Conventionally, a portable telephone (PHS: Pers)
onal Handyphone System)
When an operation of capturing a control channel is performed after communication with a base station (CS: Cell Station) is completed, a base station to be used for standby is selected as described below. That is, a control channel is received, and a base station associated with a control channel having a received signal strength equal to or higher than a certain value is selected as a base station selection candidate to be used for standby. It is determined whether or not the base station can be selected as a base station that can be used for standby regardless of the reason, and the first selection candidate determined to be selectable is set as a base station that can be used for standby.

[0003]

As described above, in the related art, a base station related to a control channel having a received signal strength of a certain value or more is set as a candidate for selecting a base station to be used for standby. Therefore, since this selection candidate includes an unnecessary base station corresponding to the base station selection failure reason, the efficiency in selecting one base station to be used in standby from this selection candidate is reduced. .

[0004] Conventionally, in a simplified portable telephone, a control channel is received even when a call operation is performed or an incoming call is detected, and a base station associated with the control channel having a received signal strength equal to or more than a predetermined value is transmitted. As a selection candidate of a base station to be used in a calling operation or a receiving operation, one base station to be used in a calling operation or a receiving operation is selected from the selection candidates. In this case as well, there is the same inconvenience as in the case of selecting one base station to be used for standby during the control channel capturing operation described above.

Accordingly, an object of the present invention is to provide a communication terminal device capable of efficiently selecting one base station to be used for standby or the like.

[0006]

According to the present invention, there is provided a communication terminal apparatus comprising: a receiving means for receiving a control channel from a base station; a first storing means for storing identification information of an unselectable base station; Second storage means for storing information on a selection candidate of a base station for communication, and identification information of a base station whose received signal strength is greater than or equal to a certain value and which is inserted into control channels received by the receiving means. Is a base station related to a control channel that is not included in the base station identification information stored in the first storage unit as a selection candidate of a base station that performs wireless communication, and stores information on the selection candidate in a second storage unit. And a base station selecting means for selecting one base station for performing wireless communication based on the information on the selection candidates stored in the second storage means.

In the present invention, the first storage means includes:
The identification information of the base station that cannot be selected is stored. When selecting a base station that performs wireless communication such as standby, calling operation, incoming call operation, etc., first, a receiving unit receives a control channel. For example, when selecting a base station to be used for standby, the control channel is received within a predetermined time from the start of the control channel acquisition operation. Further, for example, when selecting a base station to be used in a calling operation, the control channel is received within a predetermined time after the calling operation. In addition, for example, when selecting a base station to be used in an incoming call operation, the control channel is received within a predetermined time after the incoming call is detected. Then, of the received control channels, the received signal strength is equal to or more than a certain value, and the identification information of the base station inserted therein is included in the identification information of the base station stored in the first storage means. A base station related to a control channel that does not exist is a candidate for selecting a base station that performs wireless communication.

[0008] Then, based on the information on the selection candidates stored in the second storage means, one base station for performing wireless communication is selected. For example, it is determined whether or not it can be selected as a base station that performs wireless communication (a base station used for a standby, a calling operation, an incoming call operation, and the like) in order from a selection candidate having a higher priority, for example, in order of a higher received signal strength. The first selection candidate that is determined and can be selected is selected as one base station that performs wireless communication. As described above, since a base station that cannot be selected in advance is excluded from base station selection candidates for performing wireless communication, it is possible to efficiently select one base station to be used for standby or the like. .

In the case where the determination is made in the descending order of the received signal strength, the second storage means stores, as the information on the selection candidate, at least the identification information of the selection candidate and at least the control channel from the selection candidate. The received signal strength information is stored. Further, the identification information of the selection candidate determined not to be selected because it corresponds to the base station selection unavailable reason may be additionally stored in the first storage means. Further, since the reason why the base station cannot be selected may disappear, the identification information of the unselectable base station stored in the first storage unit is cleared, for example, when the power is turned off.

In the case of selecting a base station to be used for standby, for example, a second storage means stores a first storage area for storing data of group 1 and a second storage area for storing data of group 2
And information on selection candidates in the location-registered paging area is written as group 1 data in the first storage area, and the location-registered paging area is stored in the first storage area. Information on the selection candidates outside the area is written to the second storage area as group 2 data. Then, it is determined whether or not the selection candidates related to the data of group 1 can be selected as base stations to be used in standby in order from the selection candidates having the highest priority. It is determined whether or not the base station to be used as a standby base station can be selected in order from the selection candidate with the highest priority.

As described above, the selection candidate relating to group 1 is given priority over the selection candidate relating to group 2,
When the selection candidate relating to group 1 is selected as a base station to be used for standby, both outgoing and incoming calls are possible,
This is because, when the selection candidate related to group 2 is selected as a base station to be used for standby, a call can be made, but location registration is required to enable a call.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a simplified mobile phone 100 as an embodiment.

The telephone 100 includes a microcomputer, a control unit 101 for controlling the entire system, a transmitting / receiving antenna 102, and a receiving signal of a predetermined frequency captured by the antenna 102. Convert to π / 4 shift QPSK (Quadrature P
hase Shift Keying) signal and a radio section 103 for up-converting a π / 4 shift QPSK signal output from a digital modulation / demodulation section to be described later to obtain a transmission signal of a predetermined frequency. The π / 4 shift QPSK signal is demodulated to obtain received data, and TDMA (Time Division Mu
and a digital modulation / demodulation unit 104 for performing a modulation process on transmission data output from the ltiple access processing unit to obtain a π / 4 QPSK signal.

Further, telephone set 100 selects preset downlink slot data from received data (time-division multiplexed data of a plurality of slots) output from digital modulation / demodulation section 104, and separates the data into control data and compressed voice data. In addition, a TDMA for multiplexing compressed audio data output from an audio codec unit described later and control data output from the control unit 101 into a preset uplink slot.
It has a processing unit 105.

The telephone 100 includes a TDMA processing unit 1
Decoding processing (including error correction processing) is performed on the compressed audio data output from the receiver 05 to obtain a received audio signal, and compression encoding processing (including error correction code addition processing) is performed on the transmission audio signal. ) To obtain compressed audio data, and an audio codec 1
06, a low-frequency amplifier 107 for amplifying the received voice signal output from the amplifier 106, a speaker 108 as a receiver for outputting a voice based on the voice signal output from the amplifier 107, and a DTM for receiving the voice signal output from the voice codec unit 106.
When the signal is an F signal, the DTMF demodulator 109 demodulates the DTMF signal to obtain a 4-bit (1 nibble) DTMF signal code. In this case, the DTMF signal code obtained by the DTMF demodulator 109 is supplied to the control unit 101.

The telephone 100 includes a microphone 111 as a transmitter, a low-frequency amplifier 112 for amplifying an audio signal output from the microphone 111, and a DTMF signal code supplied from the control unit 101.
A DTMF modulator 113 for converting to a signal, and an amplifier 112
Output audio signal or output DT of the DTMF modulator 113
The MF signal is selectively extracted and the audio codec section 106
And a change-over switch 114 for supplying a transmission audio signal to the switch.

In this case, the output side of the amplifier 112 is connected to the fixed terminal on the a side of the changeover switch 114, and the output side of the DTMF modulator 113 is connected to the fixed terminal on the b side. The changeover switch 114 is controlled by the control unit 101, and is connected to the b side when transmitting a DTMF signal, and is connected to the a side when performing another call or the like.

The telephone 100 includes an operation unit 115 for the user to perform various key operations, a display unit 116 including a liquid crystal display, a nonvolatile memory 117, and a control unit 101 for controlling the control unit 101 when an incoming call is received. And a ring tone output section 118 for outputting a ring tone. These operation units 11
5. The display unit 116, the nonvolatile memory 117, and the ringing tone output unit 118 are connected to the control unit 101, respectively.

Here, the operation unit 115 includes a call key for instructing a call or answering an incoming call, a call termination key for ending a call, a numeric keypad for inputting a telephone number, and telephone directory data. A key or the like for searching is provided. The display unit 116 displays, in addition to the state of the system, the telephone directory data selected in the search for the telephone directory data, the telephone number input with the ten keys, and the like. Non-volatile memory 11
7 stores telephone directory data and the like.

The control unit 101 also includes a ROM (read only memory) 11 in which an operation program of the microcomputer and a conversion format for converting a DTMF signal code into a character code are written.
And a random access memory (RAM) for storing a DTMF signal code obtained by the DTMF demodulator 109, identification information of a non-selectable base station (non-selectable data list), information on a selection candidate of a base station for performing wireless communication, and the like. ) 120
And

Next, the simplified portable telephone 100 shown in FIG.
Will be described. Immediately after the power is turned on, after the communication with the base station using the communication channel is completed, and when the mobile terminal is out of the service area, the synchronization with the control channel is lost. Is performed.
That is, the control channel is received within a predetermined time after the start of the control channel capturing operation, and a selection candidate of a base station to be used in standby can be obtained. Thereafter, it is determined whether or not it can be selected as a base station to be used for standby in order from the selection candidate with the highest priority, and the first selection candidate determined to be selectable is set as a base station to be used for standby,
The standby using the base station is started. If the location has not been registered, the location registration using the communication channel is performed for the selected base station, and then the above-described operation at the time of establishing the synchronization is performed again. Details of the operation at the time of establishing the synchronization will be described later.

FIG. 2 shows a configuration example of the logical control channel (LCCH). However, the first of the TDMA frame
This is an example in which slots are allocated to a logical control channel (LCCH), and an LCCH superframe is composed of m intermittent transmission slots for each nTDMA frame.

The base station (CS) uses four slots for downlink (transmission) and four slots for subsequent uplink (reception).
The slot forms a 5 [ms] TDMA frame. And a downlink logical control channel (LCCH)
Exist for every nTDMA frame. That is, the downlink intermittent transmission cycle is 5 × n [ms].

The minimum period (5 × n × m [ms]) of the downlink logical control channel (LCCH) that specifies the slot positions of all LCCH elements is defined as an LCCH superframe. Downlink logical control channel (LCCH)
Is composed of a broadcast channel (BCCH), a paging channel (PCH), and an individual cell channel (SCCH). The BCCH is transmitted in the first slot of the LCCH super frame.
Is notified. On the other hand, the uplink logical control channel (LCCH) is configured by an individual cell channel (SCCH). The slot position of the uplink logical control channel (LCCH) is determined by the control carrier configuration information element in the radio channel information broadcast message on the BCCH.
The mobile station (PS) is notified from S).

FIG. 3 shows the configuration of the BCCH. B
CCH is a downlink one-way channel for broadcasting control information from CS to PS. The BCCH transfers information about the channel structure, system information, and the like.

The BCCH has a preamble pattern (P
R), a unique word for synchronization (UW), a channel type code (CI), a calling identification code, data (BCCH), and a cyclic error detection code (CRC). The calling identification code (CS-ID) is composed of a carrier identification code, a paging area number, and an additional ID. The data (BCCH) is composed of octet 1 to octet 8. Then, by the lower 7 bits of octet 1,
The type of message by octet 2 to octet 8 is shown.

FIG. 4 shows the configuration of the SCCH. S
CCH is a point-to-point bidirectional channel that transfers information required for call connection between CS and PS. This S
In the CCH, independent information is transferred for each cell.

The SCCH has a preamble pattern (P
R), unique word for synchronization (UW), channel type code (CI), calling identification code, destination identification code, data (SC
CH) and a cyclic error detection code (CRC). In the SCCH (downlink), the calling identification code (CS-ID) is composed of a carrier identification code, a paging area number and an additional ID, and the destination identification code is composed of a PS calling code (PS-ID). SCCH (not shown)
In (up), the above-mentioned calling identification code becomes the receiving identification code, and the above-mentioned receiving identification code becomes the calling identification code. The data (SCCH) is composed of octet 1 to octet 5. The lower 7 bits of octet 1 indicate the type of message by octet 2 to octet 5.

The PCH is a point-multipoint downlink one-way channel for simultaneously transferring the same information from the CS to the PS to a single cell or a wide area (paging area) of a plurality of cells. With this PCH, C
S notifies the PS that there is an incoming call. As shown in FIG. 2, a plurality of PCHs are included in the LCCH superframe.
CH (PCH1 to PCHn) exists.

FIG. 5 shows the configuration of the PCH. PC
H is a preamble pattern (PR), a unique word for synchronization (UW), a channel type code (CI), a calling identification code, data (PCH), and a cyclic error detection code (CR).
C). The calling identification code is composed of a carrier identification code, a paging area number, and an additional ID. The data (PCH) includes octet 1 to octet 8.

In this case, since the PCH defines only a single message, there is no area indicating the message type. 5 to 7 bits of octet 1, no call, BCD 13 digit or less PS number call service, hexadecimal 7 digit PS
A call service type such as a call service by number is displayed. The PS number is indicated by octets 1 to 7. Further, octet 8 instructs reception of a broadcast channel (BCCH). If a change occurs during intermittent reception, which will be described later, the PS receives the BCCH according to the reception instruction.

The PS recognizes a PCH to be received from a plurality of PCHs (PCH1 to PCHn) based on a paging group number. The PS is based on the PS number and the content of the BCCH (n _PCH , n _GROUP , control carrier configuration) from the CS,
The incoming call group number is calculated by equation (1). here,
n _PCH is the number of the same incoming call group, and n _GROUP is the incoming group factor. X = 2 when the incoming groups of the PCH are related to each other using two frequencies (2LCCH), and X = 1 otherwise. Incoming call group number = (PS number) MOD (n _PCH × n _GROUP × X) +1 (1)

In the standby state described above, the telephone (P
S) 100 shifts to intermittent reception in which only the PCH corresponding to the calculated paging group number is received. In this case, since the PCH corresponding to the calculated paging group number exists for each LCCH superframe, in the conventional standby state, intermittent reception is performed, for example, every 1.2 seconds.

FIG. 6 shows the operation of intermittent reception of the PCH in the standby state. It is assumed that the PCH corresponding to the destination group number is PCHa. First, the control channel is continuously received to receive the BCCH. It calculates its own paging group number from the information in the BCCH, calculates the reception timing based on the paging group number, and
Receives Ha. After that, only PCHa is intermittently received at a fixed reception timing.

The operation for making a call will be described.
In this case, for example, if a telephone number of the other party is input by key operation of the operation unit 115 or a call key is operated after searching the telephone directory data, an operation at the time of calling is performed. That is, the control channel is received within a predetermined time after the calling operation, and a selection candidate of the base station used in the calling operation is obtained. Thereafter, it is determined whether or not the selection candidate having the highest priority can be selected as the base station to be used in the calling operation, and the first selection candidate determined to be selectable is the base station to be used in the calling operation. And a calling operation using the base station is started. The details of the operation at the time of calling will be described later. In a calling operation, as is well known, after a link channel is established and a call setting operation is performed, a line connection with the other party is performed, and a transition is made to a call possible state.

Here, with reference to FIG. 7, the configuration of a communication physical slot during a call will be described. Base station (CS)
Are 4 [down (transmission) slots and 4 subsequent up (reception) slots, 5 [m
s]. PS is each TD
In the MA frame, data is transmitted to the CS in an uplink setting slot, and data in a downlink setting slot is received data.

Further, paging data is transmitted from the base station as control data using the control channel, and this paging data is supplied from the TDMA processing unit 105 to the control unit 101, and when an incoming call is detected, the incoming call data is transmitted. The operation is performed. That is, the control channel is received within a predetermined time after the detection of the incoming call, and a selection candidate of the base station to be used in the incoming call operation is obtained. Thereafter, it is determined whether or not the selection candidate having the highest priority can be selected as the base station to be used in the incoming call operation, and the first selection candidate determined to be selectable is the base station to be used in the incoming call operation. And the incoming call operation using the base station is started. Details of the operation at the time of receiving a call will be described later. In the incoming call operation, as is well known, after the link channel is established and the call setting operation is performed, a response is made by operating the call key, so that the line connection with the other party is performed and the call is ready. Move to

In the talking state, the TDMA processing unit 105 outputs the compressed voice data transmitted through the talking channel. The compressed audio data is supplied to the audio codec unit 106, where it is converted into an analog signal after being subjected to a decoding process. Then, the received audio signal output from the audio codec unit 106 is transmitted to the speaker 10 via the amplifier 107.
8 and the speaker 108 outputs a sound based on the received sound signal.

The transmission audio signal output from the microphone 111 is amplified by the amplifier 112, supplied to the audio codec unit 106, converted into a digital signal, and then compression-encoded to form compressed audio data. . Then, the compressed audio data output from the audio codec unit 106 is supplied to the TDMA processing unit 105, and transmitted to the other party through the communication channel.

Next, the control unit 101 at the time of capturing the control channel will be described with reference to the flowcharts of FIGS.
Will be described.

Immediately after the power is turned on, after the communication with the base station using the communication channel is completed, the mobile terminal is out of the service area, and the like. When the control channel capture operation starts in step ST1, it becomes available in step ST2. A search for sequentially receiving control channels of the base station is started, and a built-in timer (not shown) for obtaining an elapsed time of the search is started. Then, in step ST3, it is determined whether or not a predetermined time, for example, 100 to 150 msec has elapsed since the start of the search. If the predetermined time has not elapsed, it is determined in step ST4 whether a control channel has been received. If the control channel has not been received, the process returns to step ST3. On the other hand, when the control channel has been received, in step ST5, it is determined whether or not the RSSI (Receive Signal Strength Indicate) is equal to or higher than a zone selection level (a level that can be awaited).

If the RSSI is not equal to or higher than the zone selection level, at step ST6, the base station identification information (CS-ID), RSSI, FER (Fr
CS data such as ameError Rate) is discarded, and the process returns to step ST3. On the other hand, if the RSSI is equal to or higher than the zone selection level, it is determined in step ST7 whether or not the received base station identification information on the control channel is included in the non-selectable data list in the RAM 120.

If the base station identification information relating to the received control channel is included in the non-selectable data list, in step ST6, the received CS data relating to the control channel is discarded, and the process returns to step ST3. On the other hand, when the base station identification information related to the received control channel is not included in the non-selectable data list, in step ST8,
It is determined whether or not the location has been registered.

In this case, if the paging area number included in the received control channel is the same as the paging area number of the base station whose position is registered, it is determined that the position has been registered. If the location has been registered, in step ST9, in addition to the base station identification information (CS-ID) related to the received control channel, CS data including at least RSSI is used as group 1 data as group 1 data.
0 is written to the first storage area, and then the step S
Return to T3. On the other hand, if the location has not been registered, the same CS data is written as group 2 data in the second storage area in the RAM 120 in step ST10.
Thereafter, the process returns to step ST3.

The above operation is executed until it is determined that a predetermined time has elapsed since the start of the search in step ST3. As a result, a selection candidate of a base station to be used for standby is obtained, and the CS data of the selection candidate is included in the group 1
The data and group 2 data are written and held in the RAM 120.

Next, when a predetermined time has passed since the search was started in step ST3, in step ST11,
It is determined whether or not the first storage area in the RAM 120 has CS data as group 1 data. If there is group 1 data, the process proceeds to step ST12. In step ST12, a selection candidate having the highest priority is selected from selection candidates (base stations) related to the group 1 data, a control channel from the selection candidate is received, and system information broadcast and second system information broadcast are performed. get. For example, the priority order is determined based on the RSSI included in the CS data stored as the group 1 data, and is set higher for a candidate for a control channel with a higher RSSI.

Then, in step ST13, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the CS selection disable reason. Here, the reasons why the CS cannot be selected include RT (Radio Frequency Transmission Management) · M
M (Mobility Management) Protocol version mismatch, LCH (Link Channel) type mismatch, L
CH protocol mismatch, extended LCH protocol mismatch,
CC (Call Control) protocol mismatch, country code mismatch. Generally, these reasons are not immediately resolved.

If the reason corresponds to the CS selection impossible reason, in step ST14, the identification information (CS-ID) of the selection candidate (base station) is added to the above-mentioned selection impossible data list in the RAM 120, and the selection is made. The candidate CS data is deleted from the first storage area in the RAM 120, and thereafter, the process returns to step ST11. The contents of the non-selectable data list are cleared, for example, when the power is turned off.

On the other hand, when the reason does not correspond to the CS selection impossible reason, in step ST15, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the standby disable reason. judge. Here, the reasons for the non-standby state include the unavailable use of the selection candidate (base station) and the location registration restriction and outside the location-registered paging area. In general, these reasons may soon disappear.

If the reason corresponds to the non-standby reason, in step ST16, the CS data of the selection candidate is stored in the RAM 120.
From the first storage area in
Return to 11. On the other hand, if it is not the reason for the standby failure,
In step ST17, standby using the selection candidate (base station) is started.

When there is no group 1 data without selecting a base station to be used for standby,
Proceeding to step ST21, it is determined whether or not there is group 2 data in the second storage area in the RAM 120. If there is group 2 data, the process proceeds to step ST22. In step ST22, a selection candidate having the highest priority is selected from selection candidates (base stations) related to the group 2 data, and a control channel from the selection candidate is received.
The system information notification and the second system information notification are obtained.
For example, the priority order is determined based on the RSSI included in the CS data stored as the group 2 data, and is set higher for a selection candidate related to a control channel with a higher RSSI.

Then, in step ST23, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the above-mentioned CS selection disable reason. If the reason corresponds to the CS selection impossible reason, in step ST24, the identification information (CS-ID) of the selection candidate (base station) is added to the above-mentioned selection impossible data list in the RAM 120, and the CS of the selection candidate is added. The data is deleted from the second storage area in the RAM 120, and thereafter, the process returns to step ST21.

On the other hand, if the reason does not correspond to the CS selection unavailable reason, in step ST25, based on the system information notification and the second system information notification, the selected selection candidate is
It is determined whether or not the above-described standby reason is applicable. If it corresponds to the reason for being unable to stand by, it is determined in step ST26 whether or not the reason for being unable to stand is out of location registration restricted and outside the location-registered paging area. If so, the process proceeds to step ST27. Otherwise, step S
At T28, the CS data of the selection candidate is deleted from the second storage area in the RAM 120, and thereafter, at Step ST2
Return to 1. In step ST27, the selection candidate CS
The data is written as the group 3 data in the third storage area in the RAM 120, and the CS data of the selection candidate is deleted from the second storage area, and then the step S
Return to T21.

If it is determined in step ST25 that the reason does not correspond to the standby failure reason, in step ST29, standby using the selected candidate (base station) is started. And
Since the location of the selected base station has not been registered as described above, the location is subsequently registered in step ST30. Since this location registration is performed using the communication channel, after the location registration is completed, step ST2 is performed.
Then, the above-described operation at the time of establishing the synchronization is performed again.

When the base station to be used for standby is not selected and the group 2 data is gone,
Proceeding to step ST31, it is determined whether or not there is group 3 data in the third storage area in the RAM 120. If there is no group 3 data, the process proceeds to step ST32, for example, "out of service area" is displayed on the display unit 116, and the operation ends. On the other hand, when there is group 3 data, in step ST33, a selection candidate having the highest priority is selected from the selection candidates (base stations) related to the group 3 data, and standby using the selection candidate (base station) is performed. To start. In this case, since the base station that is waiting is under the position registration restriction, the position registration restriction of the base station is canceled and the position registration is performed.

As described above, the CS data of the selection candidate of the base station to be used in the standby mode is stored in the RAM 120 as the group 1 data and the group 2 data. In this case, since the base station that cannot be selected is excluded from the selection candidates in advance (see ST7), it is possible to efficiently select one base station to be used for standby.

When selecting a base station to be used for standby from the selection candidates, the RAM 120 stores identification information of a selection candidate (base station) determined to be unavailable for standby because it corresponds to the CS selection unavailable reason. (ST14, ST24).
reference). Therefore, when the control channel capturing operation is started and a selection candidate is obtained thereafter, the base station associated with the added identification information (CS-ID) can be removed in advance, and the base station corresponding to that can be used for standby. Base station selection efficiency can be increased.

The CS data of the selection candidate in the location-registered paging area is stored in the RAM 1 as group 1 data.
20 is written to the first storage area, and the CS data of the selection candidate outside the location-registered paging area is written to the second storage area as group 2 data (ST
9, ST10), and it is determined whether or not the selection candidates related to group 1 data can be selected as base stations to be used in standby in order from the selection candidate with the highest priority (ST).
Then, it is determined whether or not the selection candidates related to the group 2 data can be selected as base stations to be used in standby in order from the selection candidates with the highest priority (see ST21 to ST29). As described above, it is determined whether or not the selection candidate for the group 1 data can be selected as a base station to be used for standby in preference to the selection candidate for the group 2 data. There is a high possibility that one base station used for standby will be selected. Therefore, the frequency of location registration using a communication channel can be reduced, and battery consumption can be suppressed.

Next, the operation of the control unit 101 at the time of calling will be described with reference to the flowchart of FIG.

When there is a call operation in step ST41, a search for sequentially receiving control channels of available base stations is started in step ST42, and a built-in timer (not shown) for obtaining an elapsed time of this search. ) Is started. Then, in step ST43, it is determined whether or not a predetermined time, for example, 100 to 150 msec has elapsed since the start of the search. If the predetermined time has not elapsed, it is determined in step ST44 whether a control channel has been received. If the control channel has not been received, the process returns to step ST43. On the other hand, when the control channel has been received, it is determined in step ST45 whether or not the RSSI is equal to or higher than the zone selection level.

When the RSSI is not equal to or higher than the zone selection level, in step ST46, the received CS data such as base station identification information (CS-ID), RSSI, and FER for the control channel is discarded, and thereafter, the process returns to step ST43. . On the other hand, if the RSSI is equal to or higher than the zone selection level, it is determined in step ST47 whether or not the received base station identification information on the control channel is included in the non-selectable data list in the RAM 120.

If the base station identification information on the received control channel is included in the non-selectable data list, in step ST46, the received CS data on the control channel is discarded, and the process returns to step ST43. on the other hand,
If the base station identification information related to the received control channel is not included in the non-selectable data list, step ST4
In step 8, base station identification information (C
In addition to (S-ID), CS data including at least RSSI is written to a predetermined area in the RAM 120 as holding data, and thereafter, the process returns to step ST43.

The above operation is executed until it is determined that a predetermined time has elapsed since the search was started in step ST43. As a result, a selection candidate of a base station to be used in a calling operation is obtained, and the CS data of the selection candidate is stored in RAM 1.
20 is written and held in a predetermined area.

Next, if a predetermined time has elapsed since the start of the search in step ST43, the process proceeds to step ST51.
Then, it is determined whether or not there is stored data in a predetermined area in the RAM 120, that is, C as a selection candidate of a base station used in a calling operation.
It is determined whether the S data is held. When CS data is held, the process proceeds to step ST52.
In step ST52, a selection candidate with the highest priority is selected from the selection candidates (base stations) related to the held CS data, a control channel from the selection candidate is received, and the system information broadcast, the second system Get information alerts. For example, the priority order is determined based on the RSSI included in the held CS data, and is set higher for a candidate for a control channel with a higher RSSI.

Then, in step ST53, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the CS selection failure reason. The reason why the CS cannot be selected is the same as the reason why the CS cannot be selected in the above-described operation at the time of establishing synchronization. If the reason corresponds to the CS selection impossible reason, in step ST54, the identification information (CS-ID) of the selection candidate (base station) is added to the above-mentioned selection impossible data list in the RAM 120, and the CS of the selection candidate is added. The data is deleted from the held data in the RAM 120, and thereafter, the process returns to step ST51. The contents of the non-selectable data list are cleared, for example, when the power is turned off.

On the other hand, when the reason does not correspond to the CS selection impossible reason, in step ST55, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the call disabling reason. judge. Here, the call disabling reason includes that the selection candidate (base station) cannot be used and that the call is being restricted. In general, these reasons may soon disappear.

If the reason corresponds to the call disapproval reason, the CS data of the selection candidate is stored in the RAM 120 in step ST56.
Is deleted from the stored data in step ST51.
Return to On the other hand, if the reason does not correspond to the call disapproval reason, in step ST57, a call operation using the selection candidate (base station) is started.

If the base station to be used in the calling operation is not selected and the stored data is exhausted, the process proceeds to step ST58, for example, "call failure" is displayed on the display unit 116, and the operation is started. To end.

As described above, the CS data of the selection candidate of the base station used in the calling operation is stored in the predetermined area in the RAM 120. In this case, the base station that cannot be selected is excluded from the selection candidates in advance (see ST47), so that one base station used in the calling operation can be efficiently selected.

Further, when selecting a base station to be used in the call operation from the selection candidates, identification of a selection candidate (base station) determined to be unusable in the call operation because it corresponds to the CS selection unavailable reason. The information is added to the non-selectable data list in the RAM 120 (see ST54). Therefore, when there is a call operation after that, when a selection candidate is obtained, the base station associated with the added identification information (CS-ID) can be removed in advance, and only one of the base stations used in the call operation can be used. The efficiency of base station selection can be increased.

Next, the operation of the control unit 101 when receiving a call will be described with reference to the flowchart of FIG. If an incoming call is detected in step ST61, the process proceeds to step ST62.
Then, a search for sequentially receiving control channels of available base stations is started, and a built-in timer (not shown) for obtaining an elapsed time of the search is started. And
At step ST63, a predetermined time after starting the search,
For example, it is determined whether 100 to 150 msec has elapsed. If the predetermined time has not elapsed, step ST6
At 4, it is determined whether a control channel has been received. If the control channel has not been received, the process returns to step ST63. On the other hand, when the control channel is received, it is determined in step ST65 whether or not the RSSI is equal to or higher than the zone selection level.

If the RSSI is not equal to or higher than the zone selection level, in step ST66, the received CS data such as base station identification information (CS-ID), RSSI, and FER relating to the control channel is discarded, and thereafter, the process returns to step ST63. . On the other hand, if the RSSI is equal to or higher than the zone selection level, it is determined in step ST67 whether the received base station identification information on the control channel is included in the non-selectable data list in the RAM 120.

If the base station identification information related to the received control channel is included in the non-selectable data list, the received CS data related to the control channel is discarded in step ST66, and the process returns to step ST63. on the other hand,
If the base station identification information on the received control channel is not included in the non-selectable data list, step ST6
At 8, it is determined whether or not the location has been registered. In this case, if the paging area number included in the received control channel is the same as the paging area number of the base station whose position is being registered, it is determined that the position has been registered.

If the position has not been registered, step ST
At 66, the received CS data related to the control channel is discarded, and thereafter, the process returns to step ST63. On the other hand, when the location has been registered, in step ST69, in addition to the base station identification information (CS-ID) related to the received control channel,
CS data including at least RSSI is stored in RAM 120
Then, the data is written as the holding data in a predetermined area, and the process returns to step ST63.

The above operation is executed until it is determined that a predetermined time has elapsed since the start of the search in step ST63. As a result, a selection candidate of a base station to be used in the incoming call operation is obtained, and the CS data of the selection candidate is stored in RAM 1
20 is written and held in a predetermined area.

Next, if a predetermined time has elapsed since the start of the search in step ST63, the process proceeds to step ST71.
Then, it is determined whether or not there is stored data in a predetermined area in the RAM 120, that is, C as a selection candidate of a base station to be used in the incoming call operation.
It is determined whether the S data is held. When CS data is held, the process proceeds to step ST72.
In step ST72, a selection candidate having the highest priority is selected from the selection candidates (base stations) related to the held CS data, and a control channel from the selection candidate is received. Get information alerts. For example, the priority order is determined based on the RSSI included in the held CS data, and is set higher for a candidate for a control channel with a higher RSSI.

Then, in step ST73, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the CS selection failure reason. The reason why the CS cannot be selected is the same as the reason why the CS cannot be selected in the above-described operation at the time of establishing synchronization. If the reason corresponds to the CS selection impossible reason, in step ST74, the identification information (CS-ID) of the selection candidate (base station) is added to the above-mentioned selection impossible data list in the RAM 120 and the CS of the selection candidate is added. The data is deleted from the held data in the RAM 120, and thereafter, the process returns to step ST71. The contents of the non-selectable data list are cleared, for example, when the power is turned off.

On the other hand, when the reason does not correspond to the CS selection unavailable reason, in step ST75, based on the system information notification and the second system information notification, it is determined whether or not the selected selection candidate corresponds to the incoming call unavailable reason. judge. Here, the reason why the incoming call is not possible is that the selection candidate (base station) cannot be used. In general, this reason may soon disappear.

If the reason corresponds to the reason why the call cannot be received, the CS data of the selection candidate is stored in the RAM 120 in step ST76.
Is deleted from the stored data in step ST71.
Return to On the other hand, when the reason does not correspond to the reason for not being able to receive a call, in step ST77, a call receiving operation using the selected candidate (base station) is started.

If the base station to be used in the incoming call operation is not selected and the stored data is exhausted, the process proceeds to step ST78, for example, "incoming call failure" is displayed on the display unit 116, and the operation is started. To end.

As described above, the CS data of the selection candidate of the base station used in the incoming call operation is stored in the predetermined area in the RAM 120. In this case, base stations that cannot be selected are excluded from the selection candidates in advance (see ST67), so that one base station to be used in the incoming call operation can be efficiently selected.

Also, when selecting a base station to be used in the call receiving operation from the selection candidates, identification of a selection candidate (base station) determined to be unusable in the calling operation because it corresponds to the CS selection unavailable reason. The information is added to the non-selectable data list in the RAM 120 (see ST74). Therefore, when the incoming call is detected and the selection candidate is obtained thereafter, the base station related to the added identification information (CS-ID) can be removed in advance, and only one base station used for the incoming call operation can be removed. The efficiency of station selection can be increased.

In the above embodiment, the RSS
Although the priorities of the selection candidates are determined based on I, for example, the priority of the selection candidates may be determined including FER in addition to the RSSI, or the priority of the selection candidates may be determined based only on FER. You may.

In the above-described embodiment, the communication terminal device is a simple type mobile phone. However, it is needless to say that the present invention can be similarly applied to other communication terminal devices.

[0085]

According to the communication terminal device of the present invention,
From the selection candidate of the base station performing the wireless communication, based on the identification information of the non-selectable base station stored in the memory means,
The configuration excludes base stations that cannot be selected in advance, and one base station to be used for standby or the like can be efficiently selected. Further, when one base station is selected from the selection candidates, the identification information of the selection candidate (base station) determined to be unselectable because it corresponds to the base station selection failure reason is added to the memory means. Then, when obtaining a selection candidate for performing wireless communication thereafter, the base station related to the added identification information can be removed in advance, thereby increasing the efficiency of selecting one base station to be used for standby or the like. Can be.

[Brief description of the drawings]

FIG. 1 shows a simplified portable telephone (PH) as an embodiment.
It is a block diagram which shows the structure of S).

FIG. 2 is a diagram illustrating a configuration of a logical control channel (LCCH).

FIG. 3 is a diagram illustrating a configuration of a broadcast channel (BCCH).

FIG. 4 is a diagram illustrating a configuration of an individual cell channel (SCCH).

FIG. 5 is a diagram showing a configuration of a paging channel (PCH).

FIG. 6 is a diagram illustrating an operation of intermittent reception of a PCH in a standby state.

FIG. 7 is a diagram illustrating a configuration of a communication physical slot during a call;

FIG. 8 is a flowchart (1/2) illustrating the operation of the control unit when capturing a control channel.

FIG. 9 is a flowchart (2/2) showing the operation of the control unit when capturing a control channel.

FIG. 10 is a flowchart showing the operation of the control unit at the time of calling.

FIG. 11 is a flowchart showing the operation of the control unit when receiving a call.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 Simplified mobile phone 101 Control unit 102 Transmission / reception antenna 103 Radio unit 104 Digital modulation / demodulation unit 105 TDMA processing unit 106 Audio codec unit 107, 112 Low frequency amplifier 108 Speaker 109 DTMF demodulator 111 Microphone 113 DTMF modulator 114 Switching switch 115 Operation unit 116 Display unit 117 Non-volatile memory 118 Ring sound output unit

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Ryoji Terada 1-2-1 Ikenohata, Taito-ku, Tokyo F-term in Aiwa Corporation (reference) 5K067 AA14 BB04 CC06 DD13 DD19 DD23 EE02 EE10 EE24 FF02 FF03 HH23 JJ13 JJ71 JJ72 KK05 KK15

Claims (27)

[Claims] 1. A receiving means for receiving a control channel from a base station, a first storage means for storing identification information of an unselectable base station, and information on a selection candidate of a base station for performing wireless communication. A second storage unit, and, among the control channels received by the reception unit, the received signal strength is equal to or more than a predetermined value, and identification information of a base station inserted in the control channel is stored in the first storage unit. A selection candidate writing unit that sets a base station related to a control channel not included in the identification information of the base station as a selection candidate of a base station that performs wireless communication, and writes information about the selection candidate into the second storage unit; A communication terminal device comprising: a base station selecting unit that selects one base station that performs the wireless communication based on the information on the selection candidate stored in the second storage unit. 2. The communication terminal device according to claim 1, wherein the control channel received by said receiving means is a control channel received within a predetermined time by said receiving means. 3. The base station selecting means determines whether or not the selection candidate stored in the second storage means can be selected as a base station for performing the wireless communication in order from a selection candidate having a higher priority. The communication terminal apparatus according to claim 1, wherein the first selection candidate that is determined and determined to be selectable is one base station that performs the wireless communication. 4. The information regarding the selection candidate is stored in the second storage means, in addition to the identification information of the selection candidate,
The communication terminal device according to claim 3, wherein at least received signal strength information of a control channel from the selection candidate is stored, and the priority is determined using the received signal strength information. 5. An information adding means for adding and storing, to the first storage means, identification information of a selection candidate determined by the base station selection means to be unselectable because it corresponds to a base station selection failure reason. The communication terminal device according to claim 3, further comprising: 6. The communication according to claim 1, further comprising information clearing means for clearing the identification information of the non-selectable base station stored in the first storage means when the power is turned off. Terminal device. 7. A receiving unit for receiving a control channel from a base station, a first storage unit for storing identification information of an unselectable base station, and storing information on a candidate for selecting a base station to be used for standby. When performing the control channel capture operation with the second storage means, the control channel received by the receiving means has a received signal strength equal to or more than a certain value, and the identification information of the base station inserted in the received control signal is A base station related to a control channel that is not included in the base station identification information stored in the first storage means is selected as a base station selection candidate to be used in the standby mode, and information on the selection candidate is stored in the second base station. A selection candidate writing unit that writes in a storage unit, and a base station selection unit that selects one base station to be used in the standby based on the information about the selection candidate stored in the second storage unit. Communication terminal apparatus, characterized in that it comprises a means. 8. The control channel according to claim 7, wherein the control channel received by the receiving means is a control channel received by the receiving means within a predetermined time from the start of the control channel capturing operation. Communication terminal device. 9. The base station selecting means determines whether or not to select as a base station to be used in the standby in order from a selection candidate having a higher priority order among selection candidates stored in the second storage means. The communication terminal device according to claim 7, wherein the first selection candidate that has been determined and determined to be selectable is one base station used in the standby mode. 10. The selection candidate writing means, wherein the second storage means has a first storage area for storing data of group 1 and a second storage area for storing data of group 2. Writes information about the selection candidates in the location-registered paging area as the data of the group 1 in the first storage area and information about the selection candidates outside the location-registered paging area. Is stored in the second storage area as the data of the group 2, and the base station selecting means selects base stations to be used in the standby in order from the selection candidates having the highest priority with respect to the selection candidates related to the data of the group 1. It is determined whether or not the station can be selected as a station, and thereafter, the selection candidates related to the data of the group 2 are used in the standby in order from the selection candidate with the highest priority. Determining whether choices for the base station communication terminal apparatus according to claim 9, characterized in. 11. The second storage means stores, as information about the selection candidate, at least reception signal strength information of a control channel from the selection candidate, in addition to the identification information of the selection candidate, The communication terminal device according to claim 9, wherein the order is determined using the received signal strength information. 12. An information adding means for adding and storing, in the first storage means, identification information of a selection candidate determined to be unselectable because the base station selection means falls under the reason for base station selection failure. The communication terminal device according to claim 9, further comprising: 13. The information processing apparatus according to claim 7, further comprising information clearing means for clearing the identification information of the non-selectable base station stored in said first storage means when the power is turned off.
Or the communication terminal device according to 12. 14. The apparatus according to claim 11, further comprising: third storage means for storing data of group 3, wherein said selection candidate writing means is in a state in which a selection candidate relating to said data of group 2 is restricted in location registration by said base station selection means. When it is determined that there is no selection, the information on the selection candidate is written in the third storage unit, and the base station selection unit uses the selection candidate related to the data of the group 2 in the standby mode. 11. The communication terminal apparatus according to claim 10, wherein when one base station cannot be selected, the selection candidate having the highest priority among the selection candidates related to the group 3 is used as the base station used in the standby mode. . 15. The second storage means stores, as information on the selection candidate, at least reception signal strength information of a control channel from the selection candidate, in addition to the identification information of the selection candidate. The communication terminal device according to claim 11, wherein the order is determined using the received signal strength information. 16. A receiving means for receiving a control channel from a base station, a first storage means for storing identification information of an unselectable base station, and information on a candidate for selecting a base station to be used in a calling operation. A second storage unit for storing, when there is a call operation, of the control channels received by the receiving unit, the received signal strength is equal to or more than a certain value, and the identification information of the base station inserted in the control channel is A base station related to a control channel that is not included in the base station identification information stored in the first storage means is selected as a base station selection candidate to be used in the calling operation, and information on the selection candidate is stored in the first base station. Selection means writing means for writing in the second storage means, and base station selection means for selecting one base station to be used in the calling operation based on the information on the selection candidates stored in the second storage means And Communication terminal device according to claim Rukoto. 17. The control channel according to claim 16, wherein the control channel received by the receiving unit is a control channel received within a predetermined time after the calling operation is performed by the receiving unit. Communication terminal device. 18. The base station selecting means as to whether or not to select as a base station to be used in the calling operation in order from a selection candidate with a higher priority order among selection candidates stored in the second storage means. 17. The communication terminal device according to claim 16, wherein the first selection candidate that is determined to be selectable is set as one base station used in the calling operation. 19. The second storage means stores, as information on the selection candidate, at least reception signal strength information of a control channel from the selection candidate, in addition to the identification information of the selection candidate. 19. The communication terminal device according to claim 18, wherein the order is determined using the received signal strength information. 20. An information adding means for adding and storing, in the first storage means, identification information of a selection candidate determined by the base station selection means to be unselectable because it corresponds to a base station selection failure reason. The communication terminal device according to claim 18, further comprising: 21. An apparatus according to claim 1, further comprising information clearing means for clearing the identification information of the non-selectable base station stored in said first storage means when the power is turned off.
21. The communication terminal device according to 6 or 20. 22. A receiving means for receiving a control channel from a base station, a first storage means for storing identification information of a base station which cannot be selected, and information on a selection candidate of a base station to be used in an incoming call operation. A second storage unit for storing, when an incoming call is detected, among the control channels received by the receiving unit, the received signal strength is equal to or more than a certain value, and the identification information of the base station inserted in the control channel is A base station related to a control channel that is not included in the base station identification information stored in the first storage means is selected as a base station selection candidate to be used in the incoming call operation, and information on the selection candidate is referred to as the base station selection information. And a base station selecting means for selecting one base station to be used in the incoming call operation based on the information on the selection candidates stored in the second storage means. And Communication terminal and wherein the obtaining. 23. The control channel according to claim 22, wherein the control channel received by the receiving means is a control channel received within a predetermined time after the reception is detected by the receiving means. Communication terminal device. 24. Whether the base station selecting means can select as a base station to be used in the incoming call operation in order from a selection candidate having a higher priority among selection candidates stored in the second storage means. 23. The communication terminal device according to claim 22, wherein the first selection candidate that is determined to be selectable is set as one base station used in the incoming call operation. 25. The second storage means stores, as information on the selection candidate, at least reception signal strength information of a control channel from the selection candidate, in addition to the identification information of the selection candidate. The communication terminal device according to claim 24, wherein the order is determined using the received signal strength information. 26. An information adding means for adding and storing, in the first storage means, identification information of a selection candidate determined by the base station selecting means to be unselectable because it corresponds to a base station non-selection reason. The communication terminal device according to claim 24, further comprising: 27. An apparatus according to claim 2, further comprising information clearing means for clearing the identification information of the unselectable base station stored in said first storage means when the power is turned off.
27. The communication terminal device according to 2 or 26.