JPH1094032A - Portable terminal equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To select an optimum base station from plural base stations by performing the processing of position registration to the newly selected optimum base station. SOLUTION: When an opposite telephone number is inputted by a key input part 21 and a communication key is operated, control data are supplied to a TDMA processing part 15 by a microcomputer 11 and transmitted to the base station by a control channel. Thus, communication is connected and a communicable state is attained. Also, the data of the communication frequency of a communication channel and a slot position are transmitted as the control data from the base station and supplied from the TDMA processing part 15 to the microcomputer 11. The microcomputer 11 controls a radio part 13 based on the communication frequency data and matches a transmission frequency with the communication frequency of the communication channel. Further, based on the slot position data, a slot selected in the TDMA processing part 15 is set. Thus, the communication is performed by the communication channel informed by the base station.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a portable terminal device such as a portable telephone. Specifically, even if the location is registered with respect to a certain base station, an optimal base station is selected from one or a plurality of base stations that can receive and identify the control channel at predetermined time intervals, and the base station performs location registration. When the base station is different from the base station,
The present invention relates to a portable terminal device capable of constantly registering a position with an optimal base station in a communication state.

[0002]

2. Description of the Related Art Conventional portable telephones (PHS: Pers)
In the onal handyphone system, at the time of power-on, a location registration process is performed on a base station having the largest signal strength among one or a plurality of base stations that can receive and identify a control channel. Then, the position registration state is held until the signal strength of the base station whose position is registered becomes lower than the holding level (constant level).

[0003] A flowchart of FIG. 11 shows an operation at the time of power-on or the like in a conventional simplified portable telephone.

First, when the power is turned on, step ST
In step 1, the control channel is received. Then, in step ST2, the received logical control channel (LCC
H) is analyzed to detect one or a plurality of base stations that can be identified by the identification code.
(Receive Signal Strength Indicate) The signal strength of each base station is measured based on the signal.

[0005] Next, in step ST4, a base station having the maximum signal strength is selected, in step ST5, synchronization with the control channel of the selected base station is established, and in step ST6, location registration processing is performed. Then, in step ST7, it is determined whether or not the position registration is successful. If the position registration is not successful, the process returns to step ST1 and performs the same operation as described above.

If the location registration is successful in step ST7, the signal strength is measured based on the RSSI signal in step 8, and it is determined in step ST9 whether the signal strength is equal to or higher than the holding level. If the signal strength is smaller than the holding level, the process returns to step ST1 and performs the same operation as described above. On the other hand, if the signal strength is equal to or higher than the holding level, it is determined in step ST10 whether the state has transitioned. That is, it is determined whether or not a transition has been made from the standby state to the incoming call state, the outgoing call state, or the like. Step ST
In step 10, when the state has changed, the corresponding process is performed in step ST11 and the process returns to step ST8. When the state has not changed, the process immediately returns to step ST8 and performs the same operation as described above.

[0007]

As described above, in the conventional simple type portable telephone, after the location registration for a certain base station is performed, until the signal strength of the base station becomes smaller than the holding level, the conventional mobile phone performs the registration. The state of location registration is maintained. For this reason, even if a base station that is more suitable for location registration than a base station for which location registration has been performed due to movement of a terminal or the like, location registration cannot be performed again for the optimal base station, and reception signal quality is poor. I had to be content with my condition.

For example, it is assumed that a user moves from a base station A to a base station B with a terminal (simplified mobile phone) in an area where the location can be registered with a plurality of base stations. First, the terminal performs location registration for the optimal base station A having a large signal strength. However, when the user moves from the base station A to a location closer to the base station B, the signal strength of the base station B becomes the largest. However, as long as the signal strength of the base station A does not become smaller than the holding level, the position registration with respect to the base station A is not canceled and is held as it is.

In view of the above, the present invention provides a portable terminal device capable of constantly registering a position with an optimal base station in a communication state.

[0010]

SUMMARY OF THE INVENTION A portable terminal device according to the present invention measures signal strength of one or a plurality of base stations which can receive and identify a control channel, and this signal strength measuring means. Base station selecting means for selecting an optimum base station from one or a plurality of base stations based on the measurement result of the above, and position registration processing means for performing position registration processing for the optimum base station selected by the base station selecting means When the location registration processing for the optimal base station by the location registration processing means succeeds, the base station selecting means newly optimizes from one or more base stations based on the measurement result of the signal strength measuring means at predetermined time intervals. And when the newly selected optimum base station is different from the base station whose position has already been registered, the position registration processing means selects the newly selected optimum base station. In which a control means for causing the process of location registration of.

In the present invention, the signal strength measuring means measures the signal strength of one or a plurality of base stations which can receive and identify the control channel. Then, based on the signal strength measurement result, the base station selecting means selects an optimal base station from the one or more base stations. For example, the signal strength is measured a certain number of times for each of one or a plurality of base stations, and the base station with the lowest signal strength, the base station with the smallest change in signal strength, and the like are selected as the optimal base stations. You.

The location registration processing means performs location registration processing on the optimal base station selected as described above. When the location registration succeeds, the state shifts to the standby state. And when the location registration is successful,
Every predetermined time, a new optimal base station is selected from the one or more base stations by the base station selecting means based on the measurement result of the signal strength measuring means. When the newly selected optimum base station is different from the base station whose position has already been registered, the position registration processing means performs position registration processing on the newly selected optimum base station. In other words, even if the signal strength of the base station is equal to or higher than the holding level in a state where the position is registered with respect to a certain base station, if there is an optimum base station from that base station, the optimum base station Is subjected to location registration processing.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a simplified portable telephone 10 as an embodiment.

The telephone 10 includes a microcomputer 11 (hereinafter, referred to as a “microcomputer”) for controlling the entire system, an antenna 12 for transmission and reception,
2 is down-converted to a π / 4 shift QPSK (Quadrature Phase Shim).
ft Keying) signal, a radio section 13 for up-converting a π / 4 shift QPSK signal output from a digital modulation / demodulation section described later to obtain a transmission signal of a predetermined frequency, and an output from the radio section 13 The π / 4-shifted QPSK signal is demodulated to obtain received data, and TDMA (Time Division Multiple Acces
s) a digital modulation / demodulation unit 14 for modulating transmission data output from the processing unit to obtain a π / 4 QPSK signal.

The telephone 10 selects predetermined downlink slot data from received data (time-division multiplexed data of a plurality of slots) output from the digital modulation / demodulation unit 14, and separates the data into control data and compressed voice data. In addition, it has a TDMA processing unit 15 that multiplexes compressed audio data output from an audio codec unit to be described later and control data output from the microcomputer 11 into a preset uplink slot.

The telephone 10 includes a TDMA processing unit 15.
The received audio signal is obtained by performing a decoding process (including an error correction process) on the output compressed audio data, and a compression encoding process (including an error correction code addition process) is performed on the transmission audio signal. ) To obtain compressed audio data, and an audio codec 16
It has a speaker (receiver) 17 to which a received audio signal is supplied, and a microphone (speaker) 18 for supplying a transmission audio signal to the audio codec section 16.

Further, the telephone 10 instructs a call,
Key input including a call key for answering an incoming call, an end key for ending a call, a function key for changing modes such as a telephone directory registration mode, and a numeric keypad for inputting a telephone number, etc. Unit 21, a display unit 22 composed of a liquid crystal display element or the like for displaying the telephone number of the other party at the time of calling, the state of the system, and the like, and a nonvolatile memory for storing telephone directory data, redial data, and the like. 23, and a ring tone output unit 24 that outputs a ring tone under the control of the microcomputer 11 when receiving a call. The key input unit 21, the display unit 22, the non-volatile memory 23, and the ring tone output unit 24
Are connected to the microcomputer 11.

Next, the operation of the telephone 10 shown in FIG. 1 will be described.

At the time of power-on, since the synchronization with the control channel is lost, the control channel transmitted from the base station is received and the synchronization with the control channel is established. Thereafter, location registration that the user is in the area of the base station is performed. This location registration is performed using a call channel. After the location registration is completed, the mobile station returns to the control channel reception state and enters the standby state.

FIG. 2 shows a configuration example of a 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 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 (UN), a channel type code (CI), a source identification code, data (BCCH), and a cyclic error detection code (CRC). The calling identification code is composed of a carrier identification code, a paging area number, and an additional ID. In addition, data (BCCH)
Is composed of octet 1 to octet 8. The lower 7 bits of octet 1 indicate the type of message by octet 2 to octet 8.

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), a unique word for synchronization (UN), a channel type code (CI), a calling identification code, a destination identification code, and data (SC).
CH) and a cyclic error detection code (CRC). In the SCCH (downlink), the calling identification code 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). Although not shown, on the SCCH (uplink), the above-described calling identification code is a called identification code, and the above-mentioned called identification code is a calling identification code. The data (SCCH) is
It 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 a CS to a 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 (UN), 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 present embodiment, the microcomputer 11 performs power control according to the flowcharts of FIGS. Controls operations such as turning on.

First, when the power is turned on, step ST
At 11, the control channel is ready to be received. And
In step ST12, the received logical control channel (L
By analyzing the CCH), a base station that can be identified by the identification code is detected, and in step ST13, the identification code of the base station is set to A (J).

Next, in step ST14, the identification code is A
(J), the signal strength of the base station is measured.
At 5, the signal intensity is set to B. And step ST
At 16, the B is set to the minimum value C (J) and the maximum value D (J). Here, the measurement of the signal strength is performed based on the RSSI signal supplied from the wireless unit 13 to the microcomputer 11.
This is the same in the following measurement of the signal strength.

Next, in step ST17, the identification code is A
(J), the signal strength of the base station is measured.
At 8, the signal strength is set to B. And step ST
At 19, it is determined whether or not C (J)> B. C (J)>
If B, in step ST20, C (J) = B, and the minimum value C (J) is updated. On the other hand, if C (J)> B is not satisfied, the minimum value C (J) is not updated and step S
Proceed to T21.

In step ST21, it is determined whether or not D (J) <B. If D (J) <B, at step ST22, D (J) = B and the maximum value D (J) is updated. On the other hand, if D (J) <B, the process proceeds to the next step without updating the maximum value D (J).

The above-mentioned steps ST17 to ST2
Operation 2 is repeated n times. As a result, the signal strength of the base station whose identification code is A (J) is measured n times, and its minimum value C (J) and maximum value D (J) are obtained. Further, the above-described operations of steps ST11 to ST22 are repeated m times. This m times is equal to the number of base stations that can be identified by the identification code. Thus, the identification codes A (1) to
For the base station of A (m), the minimum signal strength C
(1) to C (m) and the maximum values D (1) to D (m) are obtained.
9 is stored in a memory (not shown) in the microcomputer 11.
As shown in the table, a data table in which minimum values C (1) to C (m) and maximum values D (1) to D (m) are recorded corresponding to the identification codes A (1) to A (m). (Before sorting) is formed.

Next, in step ST23, G = 0, and
In step ST24, it is determined whether or not C (I)> G. If C (I)> G, G is determined in step ST25.
= C (I), and in step ST26, H = I, and the process proceeds to step ST27. On the other hand, when C (I)> G is not satisfied, the process immediately proceeds to step ST27.

Then, in step ST27, P (J) = D
(H), and in step ST28, Q (J) = C (H),
In step ST29, R (J) = A (H) and step S
At T30, C (H) = 0, and the process proceeds to the next step.

Steps ST24 to ST2 described above
Step 6 is repeated m times. Thereby, the minimum value C
The largest C (H) is selected from (1) to C (m), and the corresponding identification code A (H) is determined in step ST29.
Are set to the priority order J. Then, in step ST30, the minimum value C (H) corresponding to the base station that has already been determined to the priority order J is removed from the selection targets in steps ST24 to ST26. Further, the operation of steps ST23 to ST30 is repeated m times. Thereby, the priorities are set for the base stations of the identification codes A (1) to A (m). In this case, the priorities of the base stations of the identification codes A (1) to A (m) are in the order of the smallest signal strength.

Then, in the memory of the microcomputer 11, for example, as shown in FIG.
A data table (after sorting) in which .about.A (m) are sorted is formed. As will be described later, in the present embodiment, only the base station with the highest priority order needs to be found, and the above-described processing for setting the priority order of 2 to m can be omitted.

Next, in step ST31, the sorting result
That is, it is determined whether or not the base station with the highest priority, which is the optimum base station, is the same as the previous base station. If not the same as the previous time, the process proceeds to step ST32. Immediately after power-on, 1
At the time of the second time, it is determined that it is not the same as the previous time. On the other hand, if it is the same as the previous time, it is determined in step ST33 whether or not the position is already registered. If the position has not been registered, the process proceeds to step ST32 because the position needs to be registered. If the position has already been registered, the process does not need to be performed again, and the process immediately proceeds to step ST37.

In step ST32, the base station with the highest priority is selected as the most suitable base station based on the data table. In step ST33, synchronization with the control channel of the base station is established. Perform the registration process. Then, in a step ST35, it is determined whether or not the position registration is successful. If the location registration is not successful, the process returns to step ST11 and performs the same operation as described above.

If the location registration has succeeded in step ST35, the process shifts to the standby state and proceeds to step ST35.
Proceed to 37. In step ST37, the signal strength of the base station that performs location registration is measured, and in step ST38, it is determined whether the signal strength is equal to or higher than the holding level. If the signal strength is smaller than the holding level, step ST11
Then, the same operation as described above is performed.

If the signal strength is equal to or higher than the holding level in step ST38, it is determined in step ST39 whether or not the state has changed. That is, from the standby state,
It is determined whether a transition has been made to an incoming call state, a calling state, or the like. If the state has changed in step ST39, the process proceeds to step S39.
At T40, a corresponding process is performed. Step ST described above
After repeating the operations from 37 to ST40 L times, that is, for a predetermined time, the process returns to step ST11 to perform the same operations as described above. Thereby, even if the signal strength of the base station performing the location registration is equal to or higher than the holding level,
After a predetermined time, a new data table is created.
If the base station with the first priority is not the same as the last base station, the base station with the first priority is selected as the optimal base station, and the location registration process is performed again.

In the operation according to the flowcharts of FIGS. 6 to 8, even if the signal strength of the base station performing the location registration is equal to or higher than the holding level, a new data table is created at predetermined time intervals and the priority is given. If the base station with the highest priority is not the same as the last base station, the base station with the first priority is selected as the optimum base station and the position registration process is performed again. For this reason, there is an advantage that the location can be registered with the base station in the communication state that is always optimal.

Also, in the telephone 10 shown in FIG.
Alternatively, when the call key is operated after searching the redial data or telephone directory data, first, the microcomputer 11 supplies telephone number data and the like as control data to the TDMA processing unit 15 and transmits the data to the base station through a control channel. As a result, the line connection with the other party is established, and a call is made possible.

Here, the communication is performed using a communication channel. At the time of the line connection processing, the communication frequency and slot position data of the communication channel are transmitted as control data from the base station using the control channel, and the TDMA processing is performed. The data is supplied from the unit 15 to the microcomputer 11. The microcomputer 11
The radio section 13 is controlled based on the communication frequency data so that the transmission / reception frequency matches the communication frequency of the communication channel, and the slot selected by the TDMA processing section 15 is set based on the slot position data. Therefore, the call is made using the call channel notified from the base station.

Also, call data is transmitted as control data from the base station using the control channel, and this call data is supplied from the TDMA processing unit 15 to the microcomputer 11 and when the incoming call is detected, the microcomputer 11 makes a call sound. The output unit 24 is controlled to output a ringing tone.

While this calling operation is being performed,
When the call key is operated and there is a response, response data is supplied from the microcomputer 11 as control data to the TDMA processing unit 15 and transmitted to the base station via the control channel. As a result, the line connection with the other party is established, and a call is made possible. Also in this case, the communication is performed using the communication channel notified from the base station.

In the talk state, the compressed voice data transmitted through the talk channel is output from the TDMA processing unit 15. The compressed audio data is supplied to the audio codec 16 and subjected to a decoding process, and then converted into an analog signal. Then, the received audio signal output from the audio codec section 16 is supplied to the speaker 17 and the speaker 1
7 outputs a sound.

The transmission audio signal output from the microphone 18 is supplied to the audio codec 16 and converted into a digital signal, which is then subjected to a compression encoding process to form compressed audio data. Then, the audio codec section 16
The output compressed audio data is supplied to the TDMA processing unit 15 and transmitted to the other party through a communication channel.

In the above embodiment, the data table is created at predetermined time intervals in the standby state.
Although it has been described that the process of selecting the optimum base station and re-executing the position registration is performed, the same process may be performed by interruption every predetermined time during a call.

In the above embodiment, the data table corresponds to the base stations of the identification codes A (1) to A (m), and the minimum value C (1) to C (m) and the maximum value D ( 1) to D (m)
Are recorded, but when determining the priority order in which the minimum value is large as described above, the maximum values D (1) to D (m) are unnecessary, and the recording thereof is unnecessary. It is.
However, when determining the priority order in which the change amount, which is the difference between the minimum value and the maximum value, is small, the minimum values C (1) to C (m)
And the maximum values D (1) to D (m) are both required. In this case, the change amount itself may be recorded in the data table. Furthermore, when determining the priority order in which the maximum value is large, only the maximum values D (1) to D (m) need to be recorded.

In the above-described embodiment, the present invention is applied to a simple type portable telephone. However, the present invention is applied to other portable terminal devices which need to register a position in a base station and shift to a standby state. Can of course be applied in the same manner.

[0055]

According to the present invention, even when a location is registered with respect to a certain base station, an optimum base station is selected from one or a plurality of base stations which can receive and identify a control channel at predetermined time intervals. However, when the base station is different from the base station whose position is registered, the position registration is retried, and there is an advantage that the position can be registered with the base station in the best communication state at all times.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a simplified mobile phone as an embodiment.

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

FIG. 3 is a diagram showing a configuration of a BCCH.

FIG. 4 is a diagram illustrating a configuration of an SCCH.

FIG. 5 is a diagram showing a configuration of a PCH.

FIG. 6 is a flowchart (1/3) showing an operation at the time of power-on and the like in the embodiment.

FIG. 7 is a flowchart (2/3) showing an operation at the time of power-on and the like in the embodiment.

FIG. 8 is a flowchart (3/3) showing an operation at the time of power-on and the like in the embodiment.

FIG. 9 is a diagram showing a data table (before sorting) created in the embodiment.

FIG. 10 is a diagram showing a data table (after sorting) created in the embodiment.

FIG. 11 is a diagram showing an operation at power-on and the like in a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Simplified mobile phone 11 Microcomputer 12 Transmission / reception antenna 13 Radio unit 14 Digital modulation / demodulation unit 15 TDMA processing unit 16 Audio codec unit 17 Speaker (receiver) 18 Microphone (transmitter) 21 Key input unit 22 Display unit 23 Non-volatile memory 24 Ring output section

Claims (3)

[Claims] 1. A signal strength measuring means for measuring a signal strength of one or a plurality of base stations capable of receiving and discriminating a control channel, and said one or more base stations based on a measurement result of said signal strength measuring means. Base station selecting means for selecting an optimal base station; position registration processing means for performing position registration processing for the optimal base station selected by the base station selecting means; and the optimal base by the position registration processing means. When the location registration is successful in the location registration process with respect to the station, the base station selecting means is provided with a new optimal base station from the one or more base stations at predetermined time intervals based on the measurement result of the signal strength measuring means. And when the newly selected optimum base station is different from the base station whose position has already been registered, the position registration processing means selects the newly selected optimum base station. And a control means for performing a location registration process for the portable terminal device. 2. The method according to claim 1, wherein the base station selecting unit performs the signal strength measurement on the one or more base stations by the signal strength measuring unit a predetermined number of times. The portable terminal device according to claim 1, wherein an optimal base station is selected. 3. When the location registration is not successful in the location registration processing for the optimal base station by the location registration processing means, the base station selecting means is configured to transmit the one or more information based on the measurement result of the signal strength measuring means. Control means for selecting a new optimal base station from a plurality of base stations and causing the location registration processing means to perform location registration processing for the newly selected optimal base station is further provided. The portable terminal device according to claim 1.