JP2000287246A - Radio communication terminal - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication terminal which changes conditions to activate base station search and can provide connection to the base station of more excellent speech quality by switching plural decision conditions for deciding switching of a connector and deciding whether or not switching of the connector is performed by a switched decision condition. SOLUTION: A memory 6 is provided with a table 67 where decision condition information is stored and a table 68 where identification information of a specific base station is to be stored. A base station search means 57 performs base station search and a decision condition selecting means 58 selects the decision condition information and performs switching to a base station where speech quality is excellent. Thus, since plural decision conditions to be used in deciding that a connection base station is to be switched are prepared and a plurality of decision conditions are switched, it is possible to make it easier to begin the base station search by the selected decision condition, to largely reduce an uncomfortable feeling of a user or a situation in which the user cannot speak depending upon the condition of a mobile communication device and to improve a transmission speed in data communication.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable telephone or PHS (personal digital
The present invention relates to a wireless communication terminal that performs communication by connecting to any one of a plurality of base stations, such as a terminal of a handy horn system.

[0002]

2. Description of the Related Art In a small cell type radio system such as a PHS system, the installation density of radio base stations is high in urban areas and low in suburbs in order to make up for traffic differences. Further, in the PHS system, since the radio zone of the base station is narrow, the connected base station is switched to another base station (performs base station handover) due to deterioration of the communication quality due to movement of the terminal and changes in the surrounding environment. The situation is likely to occur. In such a case, the criterion at the time of shifting to the base station search in the mobile terminal used in the PHS system is uniform regardless of the base station installation density, and is adapted to the case where the base station installation density is low. That is, a search criterion is set so that a search for another base station is started under the limit condition that a certain level of communication quality can be ensured, and handover to a base station with more stable communication quality is performed.

In an area where the base station installation density is high, there are many cases where a plurality of connectable base stations exist simultaneously. Therefore,
During a call, there is a high possibility that a base station with more stable call quality will appear. However, at present, since the criterion for executing the base station search is based on the case where the base station installation density is low, even if there is a base station with more stable communication quality, the communication quality is degraded more than this criterion. Or, there has been a problem that the search for the base station is not performed unless the handover instruction is given from the base station.

In recent years, in addition to the mobile terminal automatically searching for a base station as described above, a PHS terminal that searches for a base station in accordance with an instruction from a user has appeared. However, it is based on searching for a base station having better communication quality.

[0005] However, when a call is made by connecting to the base station selected by the above base station search, a base station having better call quality is selected from only the measured values. However, it is not always the case that the user actually talks and is in a comfortable talking state. That is, a base station having a strong electric field strength or the like and a base station having little noise or echo are not always limited.

Therefore, even if the base station is searched automatically or instructed by the user and a connection to a different base station is made, a comfortable communication state is not always realized, and a low transmission rate is required for data communication. There was a problem that communication was possible only with the Internet.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the problems of the conventional wireless communication terminal such as a PHS terminal and the like, and an object thereof is to change a condition for starting a base station search. Another object of the present invention is to provide a wireless communication terminal capable of realizing connection with a base station having better call quality. Another object is to provide a wireless communication terminal capable of realizing a comfortable call state in a specific place.

[0008]

SUMMARY OF THE INVENTION A wireless communication terminal according to the present invention detects whether or not to switch a connection device based on a state of a wireless line with a connection device connected to a wired line. When switching the connection device, in the wireless communication terminal that searches for another connection device, a plurality of determination conditions for determining switching of the connection device are switched by a predetermined operation, and switching of the connection device is performed based on the switched determination condition. It is characterized by comprising control means for determining whether or not to perform. As a result, it is possible to detect whether or not to switch the connection base station and switch the determination condition used when determining to switch, thereby making it easier to perform a base station search.

A wireless communication terminal according to the present invention provides a wireless communication terminal based on a state of a wireless line with a connection device connected to a wired line.
Storing means for detecting whether or not to switch the connection device and, when switching the connection device, storing a plurality of determination conditions for determining the switching of the connection device in a wireless communication terminal that searches for another connection device. And switching means for switching the determination conditions stored in the storage means.
Therefore, base station search can be easily performed by detecting whether or not to switch the connection base station and selecting a determination condition used for determination.

[0010] A wireless communication terminal according to the present invention is provided based on a state of a wireless line with a connection device connected to a wired line.
Control means for instructing to switch the connection to another connection device; a wireless communication terminal for connecting to another connection device in accordance with an instruction from the control device; storing identification information for identifying the connection device; Connection means for connecting to a connection device corresponding to the identification information to be connected. Thereby, when the user can comfortably talk, the identification information of the base station is registered, and the connection can be controlled again to the corresponding base station by using the registered identification information according to the instruction.

[0011] The wireless communication terminal according to the present invention, based on the state of the wireless line with the connection device connected to the wired line,
A wireless communication terminal for connecting to another connection device according to an instruction from the control device, the storage device storing identification information for identifying the connection device; Storage means for storing identification information of a connection device connected via a wireless line in the storage means, and connection means for connecting to a connection device corresponding to the identification information stored in the storage means. It is characterized by the following. Thereby, when the user can communicate comfortably, the identification information of the base station is registered, and the connection can be controlled again to the corresponding base station using the registered identification information in accordance with the instruction.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A radio communication terminal according to the present invention will be described below with reference to the accompanying drawings. In each drawing, the same components are denoted by the same reference numerals, and redundant description will be omitted.
In the following description, a PHS terminal is taken as an example, but other wireless communication devices such as a mobile phone can be similarly configured. As shown in FIG. 1, the telephone includes a radio unit 1 having an antenna 11, a modem unit 2, a TDMA unit 3, a communication unit 4, a control unit 5, and a power supply unit 7. The control unit 5 includes an operation unit 51 including various keys, a touch panel, and the like.
An LCD (liquid crystal display) 52, an LCD controller 53 for controlling the LCD 52, a sounder 54 for generating a ringing tone, and a vibrator 59 for notifying an incoming call by vibration are connected.

In the above telephone, a radio frequency signal arriving from the home base station BSH or the public base station BSP is received by the antenna 11, and the radio frequency switch (S
W) The receiving unit 13 is reached via 12. In the receiving unit 13, the radio frequency signal received as described above is mixed with a receiving local oscillation signal generated from the frequency synthesizer 14 and converted into a receiving intermediate frequency signal. The local oscillation frequency generated by the frequency synthesizer 14 is instructed by the control unit 5 according to the radio channel frequency. The radio unit 1 includes a reception field strength detection unit (RSSI) 1
6 are provided. The reception field strength detection unit 16 detects the reception field strength RSSI of the radio frequency signal arriving from the home base station BSH or the public base station BSP, and notifies the control unit 5 of the detected value.

The received intermediate frequency signal output from the receiving section 13 is sent to the digital demodulation circuit 21 of the modem section 2. The digital demodulation circuit 21 digitally demodulates the received intermediate frequency signal, thereby reproducing a digital communication signal.

The TDMA decoder 31 of the TDMA unit 3
In accordance with an instruction from the control unit 5, a digital communication signal is extracted from a time slot assigned to the own device, and the extracted digital communication signal is transmitted to the communication unit 4. The communication unit 4 uses an adaptive differential PCM codec (ADPCM-COD).
EC) 41 and a PCM codec (PCM-CODE)
C) 42, and the digital speech signal is sequentially decoded by the adaptive difference PCM codec 41 and the PCM codec 42 to reproduce an analog speech signal.
The reproduced analog call signal is output from the speaker 43 after being amplified by a receiver amplifier (not shown).

On the other hand, the transmitted voice input to the microphone 44 is sequentially encoded by the PCM codec 42 and the applied differential PCM codec 41 to be a digital speech signal. In the TDMA encoder 32, the digital communication signal transmitted from the adaptive difference codec 41 is inserted into a time slot specified by the control unit 5 and transmitted to the digital modulation circuit 22. In the digital modulation circuit 22, the carrier signal is modulated by the digital communication signal, and the modulated signal according to the modulation result is transmitted to the transmission unit 15. In the transmitting section 15, the modulated signal is mixed with the transmitting local oscillation signal generated from the frequency synthesizer 14 to be frequency-converted to the radio channel frequency specified by the control section 5 and further amplified to a predetermined transmission power level. Is done. The radio frequency signal transmitted from the transmitting unit 15 is transmitted from the antenna 11 via the high frequency switch 12 to the home base station BSH or the public base station BS.
Sent to P.

The power supply unit 7 includes a battery 71 composed of a secondary battery.
And the output voltage of the battery 71 is changed to a predetermined operating voltage Vcc.
And a power supply circuit 72 for converting the power supply to In the above, the transmission unit 15, the digital modulation circuit 22, and the TDMA encoder 32 constitute a transmission system for transmitting data, and the reception unit 13, the digital demodulation circuit 21, and the TDMA decoder 3
1 constitutes a receiving system for receiving data. The transmission system can be in a battery saving state in preparation for data transmission, in which state power consumption is reduced.

FIG. 2 shows a front view of the terminal according to the present embodiment. An LCD 52 is provided on the surface of the terminal housing, and displays a message input by the terminal, a message arriving via a wireless line, and other image data. Further, a key input unit 55 including a cursor key and a dial key for moving a cursor displayed on the LCD up, down, left, and right is provided. Further, between the LCD 52 and the key input unit 55, it functions as a hook key 56a for answering a call or an incoming call and ending the call, and as a switching unit for switching a determination condition used when determining to switch the connection base station. A condition switching key 56b, a switching instruction key 56c functioning as a switching instruction unit for instructing switching of a base station to be connected, a registration request key 56d used for making a registration request for a specific base station, and an instruction for connecting to a specific base station. Is provided, and constitutes a part of the operation unit 51. All or some of these keys may be provided on the side surface of the housing or the like in consideration of operability.

As shown in FIG. 1, the control unit 5 includes a base station search unit 57, a judgment condition selection unit 58, a storage control unit 61, a specific base station connection control unit 62, and a display control unit 6.
3 are provided. The memory 6 includes a table 67 in which determination condition information is stored and a table 68 in which identification information of a specific base station is stored. Here, the determination condition information is information of a determination condition used when determining to switch the connection base station. The identification information of the specific base station is the identification information of the base station (specific base station) instructed to register by the user among the identification information of the base station transmitted by the base station.

A specific example of the judgment condition information will be described with reference to FIGS. The determination condition information A is, as shown in FIG.
Frame error rate FER (Frame error rate: 240
This is a parameter indicating how many frame errors occur in a frame (1.2 sec).
ec), if the unique word of the own slot (0.625 msec) does not correspond to “error of 1 bit or less”,
A case where the CRC decoding check does not correspond to “no error” is regarded as a frame error. ) Is the first value FER
If the condition is greater than or equal to 1 or the field strength RSSI is less than or equal to the first value RSSI1, that is, if the communication quality is within the range of the hatched area in FIG. 3, it is determined that the currently connected base station and others are to be switched to another base station. Information. However, the condition is that the call quality is detected m times continuously (COUNT1) that the call quality is in the range of the hatched portion in FIG. 3 when the call quality is detected. The bit error of the unique word and the CRC decoding check are performed in the TDMA decoder 31.

On the other hand, as shown in FIG. 4, the determination condition information B includes a condition that the frame error rate FER (frame error rate) is equal to or more than a second value FER2 or the field strength RSSI is equal to or less than a second value RSSI2. In other words, this is information for determining that the currently connected base station is to be switched to another base station when the communication quality is in the range indicated by the diagonal lines in FIG. However, when the call quality is detected, it is continuously (n <m) times (COUNT <) that the call quality is in the range of the hatched portion in FIG.
2) Condition is to be detected.

In the terminal configured as described above, the control unit 5 executes the program of the flowchart shown in FIG. By selecting condition information, switching to a base station having better communication quality is performed. That is, when a call is started or during a call, it is detected which of the determination condition information A and B is selected (S1). The user can select either A or B of the determination condition information using the condition switching key 56b shown in FIG. Here, when it is detected that the judgment condition information A is selected, the frame error rate FER is measured, it is detected whether the result is equal to or more than the first value FER1, and the field strength RSSI is measured. The result is first
Is detected to be less than or equal to the value RSSI1, and it is detected whether at least one of the values is applicable (S2).

When branching to YES in step S2, the corresponding count is incremented (S3), and the corresponding number m
Is determined (S4). Then, steps S2 and S3 are repeated until the number m is reached, and when the number m is reached, a base station search is executed (S6). That is, a search is performed to determine whether there is another base station that is currently connected and does not satisfy the determination condition information A. As a result, if a base station having a vacant channel that does not satisfy the determination condition information A can be searched, handover (connection switching) to this suitable base station is performed. If another base station cannot be searched, the terminal is currently connected. The connection with the base station is continued (returned) (S7).

On the other hand, when it is detected that the determination condition information B is selected, the frame error rate FER is measured, and it is determined whether the result is equal to or more than the second value FER2. Then, the electric field strength RSSI is measured, and it is detected whether the result is equal to or less than the second value RSS2, and it is detected whether at least one of them is applicable (S8). The criterion of the determination condition information B is looser than that of the above-described determination condition information A, and the condition is easily satisfied.

If step S8 branches to YES, the corresponding count is incremented (S9), and the corresponding number n
Is determined (S10). And the corresponding number n
Steps S8 and S9 are repeated until
Then, a base station search is executed (S11). Here also, since n <m, the condition is easily satisfied. And a base station different from the currently connected base station,
A search is performed to determine whether there is a base station that does not satisfy the determination condition information B. As a result, a base station having an empty channel that does not satisfy the determination condition information B can be searched (other base stations can be easily found because the determination condition information B is employed).
And handover to this preferred base station (connection switching)
If the search is not successful, the connection with the currently connected base station is continued (switched back) (S12).

As described above, two types of condition information for transitioning to a search for another base station having better communication quality are prepared, and for example, a condition for transitioning to a search for a base station in response to a user instruction. Can be loosened or strict,
Appropriate connection switching with the base station can be performed according to the level of the base station installation density. And, in an area where the installation density of the radio base stations is high, such as in an urban area, since different determination condition information B is provided, the user can select this determination criterion, and the terminal can select a base having stable communication quality. The probability of being connected to a station can be higher than before. Further, in the above-described embodiment, the determination condition information A and B are described as being used. However, the determination condition information is not limited to two pieces of information, but may be a plurality.

As described above, in the connection switching with the base station based on the communication quality, a comfortable and good communication cannot always be performed. Therefore, in the present terminal, as shown in FIG. 6, a plurality of base stations are located in a specific place S where the user's movement amount is not so large, such as a room at home or work, and the comfort and goodness of the call do not change significantly. In some service areas. For example, in the figure, the mobile station is located in the service area of the base stations CS-1 and CS-2, but is far from the specific place S and has a lower communication quality such as electric field strength than the specific base station CS-2. Suppose that a comfortable and good call can be made when connected. In such a case, the identification information of the specific base station CS-2 is stored, and when the user is at the specific location S, a connection with the specific base station CS-2 is obtained based on the stored identification information. .

The terminal configured as described above functions as storage control means 61 by executing the program of the flowchart shown in FIG.
Registration of CS-ID, which is the identification information of, is enabled. That is, the control unit 5 detects whether a registration request for a specific base station has been input (S15). CS-ID of this specific base station
The registration request can be made by operating the registration request key 56d shown in FIG. 2 during a comfortable and favorable call. Here, the CS-I of the specific base station
If there is no D registration request, it is detected whether an instruction to switch base stations has been input (S16). The instruction for base station switching is
It can be performed by operating the switching instruction key 56c shown in FIG.

In FIG. 6, when the switching instruction key 56c is operated when there is a lot of noise or echo during a call while being connected to the base station CS-1, the currently connected base station CS-1 is operated.
-1 to detect whether there is another base station, by receiving the identification information CS-ID transmitted from the base station, and determining an appropriate base station (communication quality) based on the selected determination condition information (A or B). Is searched for, and in this example, the base station CS-2 is detected and switching is performed (S17). If there is no base station whose speech quality is appropriate in relation to the determination condition information, no switching occurs.

When the connection base station is switched as described above and the process returns to step S17, the user can make a good call, and operates the registration request key 56d. In response, the flow branches to YES in step S15, and the base station C
The identification information (CS-ID) of S-2 is stored in the table 68 of the memory 6 (S18). If the operation of the switching instruction key 56c cannot be detected in step S16, the base station search and handover processes described in FIG. 5 are executed automatically (S19).

The control unit 5 of the terminal executes a program corresponding to the flowchart of FIG. 8 so that a connection with a specific base station CS-2 can be obtained based on the identification information registered as described above. It functions as the specific base station connection control means 62 and the display means 63. That is, it is detected whether or not an instruction to connect to the specific base station has been issued in the call state (S21). This instruction can be input by the user operating the connection instruction key 56e shown in FIG. When an instruction to connect to a specific base station is issued, based on the identification information (CS-ID) of the base station CS-2, which is the specific base station, stored in the table 68 of the memory 6, It is detected whether there is a vacancy in the second line (S22).

Here, the base station CS-2, which is a specific base station,
If no line is available, it is detected whether a preset number of re-searches has been reached (S24). If the number of times of re-search has not been reached, the processes of steps S22 and S23 are performed again to detect a free line of the base station CS-2. During this repetition, if a line vacancy of the base station CS-2 is detected, connection with the base station CS-2, which is a specific base station, is made (S25). And the base station CS which is the specific base station
-2 is displayed on the LCD 52, for example, "Connected to the designated base station" (S26), and it is detected whether or not switching by normal handover occurs (S27). ). The switching by the handover includes the switching by the process described with reference to the flowchart of FIG. 5 and the switching by the base station.

If switching by handover does not occur in the above, the connection with the specific base station CS-2 is continued (S28). On the other hand, if switching by handover occurs, the base station as specific base station is generated. The connection with the CS-2 is released (S29), the connection with another base station detected as a result of the base station search is made (S30), and the automatic base station search by the process described with reference to the flowchart of FIG. (S31).

When the number of re-searches is reached during the repetition of steps S22 and S23, base stations other than the specific base station (including the currently connected base station)
Is established (S32), and the process proceeds to the automatic base station search by the processing described with reference to the flowchart of FIG. 5 (S33).

As described above, the communication distance such as the electric field strength is inferior to that of the base station CS-1 due to the distance from the specific place S, but it is connected to the specific base station CS-2 capable of making a comfortable and good call. A call can be made, and user satisfaction can be obtained. The specific location is not limited to one, but may be a plurality of locations, and each specific location may be displayed as “specific location 1”, “specific location 2”, or the like by a key operation so that it can be designated. Further, instead of storing the identification information of one specific base station for one specific location, the identification information of a plurality of specific base stations may be stored and selected for connection.

The terminal performs only the processing according to the program corresponding to FIGS. 7 and 8 and does not perform the processing according to the program for providing a plurality of determination condition information shown in FIG. A terminal that performs processing using the type of determination condition information can also be realized. Further, it is also possible to realize a terminal that includes only a plurality of pieces of determination condition information shown in FIG. 5 and performs only processing by a program for selection, and does not perform the processing shown in FIGS. 7 and 8.

[0037]

As described above, according to the radio communication terminal of the present invention, a plurality of determination conditions used when determining to switch the connection base station are prepared, and the plurality of determination conditions are switched. Base station search can be easily performed by the determined determination condition, and the discomfort of the user or the situation where a call cannot be made can be greatly reduced depending on the condition of the mobile communication device, and the transmission speed is improved in data communication. Can be.

Further, according to the wireless communication terminal of the present invention, when the user can comfortably talk, the identification information of the base station is registered, and the registered base information is used by using the registered identification information according to the instruction. Since the connection control to the station is performed, the user can realize a comfortable call.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a wireless communication terminal according to the present invention.

FIG. 2 is a plan view of a PHS terminal as an example of the wireless communication terminal according to the present invention.

FIG. 3 is an explanatory diagram of judgment condition information A used in the wireless communication terminal according to the present invention.

FIG. 4 is an explanatory diagram of judgment condition information B used in the wireless communication terminal according to the present invention.

FIG. 5 is a flowchart showing an operation of selecting a plurality of pieces of determination condition information by the wireless communication terminal according to the present invention.

FIG. 6 is a diagram illustrating registration of a specific base station by a wireless communication terminal according to the present invention.

FIG. 7 is a flowchart showing an operation of registering a specific base station by the wireless communication terminal according to the present invention.

FIG. 8 is a flowchart showing an operation of connecting to a specific base station by the wireless communication terminal according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Radio part 2 Modem part 3 TDMA part 4 Talk part 5 Control part 6 Memory 7 Power supply part 51 Operation part 52 LCD 53 LCD control part 54 Sounder 55 Key input part 56a Hook key 56b Condition switching key 56c Switching instruction key 56d Registration request key 56e Connection instruction key 57 Base station search means 58 Judgment condition selection means 61 Storage control means 62 Specific base station connection control means 63 Display control means

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masato Donaka 3-1-1 Asahigaoka, Hino-shi, Tokyo F-term in the Toshiba Hino Plant (reference) 5K027 AA11 BB03 CC08 5K067 AA13 AA15 BB04 DD19 DD44 DD46 EE02 EE10 FF13 FF15 GG01 GG11 HH05 HH23 JJ11 JJ31 JJ72 JJ78

Claims (7)

[Claims] 1. A method for detecting whether to switch a connection device based on a state of a wireless line between the connection device and a connection device connected to a wired line. A wireless communication terminal performing a search, comprising: control means for switching a plurality of determination conditions for determining switching of a connected device by a predetermined operation, and determining whether to switch the connected device based on the switched determination condition. A wireless communication terminal characterized by the above-mentioned. 2. A method for detecting whether to switch a connection device based on a state of a wireless line between the connection device and a connection device connected to a wired line. A wireless communication terminal performing a search, comprising: storage means for storing a plurality of determination conditions for determining switching of a connection device; and switching means for switching the determination conditions stored in the storage means. Terminal. 3. The wireless communication terminal according to claim 1, wherein the determination condition is whether the frame error rate and the received electric field strength satisfy predetermined values. 4. The wireless communication terminal according to claim 1, wherein the determination condition is whether or not the number of times that the frame error rate and the received electric field strength satisfy a predetermined value is continued a predetermined number of times. 5. A control unit for instructing switching of connection to another connection device based on a state of a wireless line with a connection device connected to a wired line, and the control unit instructing another connection device to issue an instruction. What is claimed is: 1. A radio communication terminal for connecting to a connection device, comprising: identification means for identifying the connection device; and connection means for connecting to the connection device corresponding to the stored identification information. . 6. A control unit for instructing switching of connection to another connection device based on a state of a wireless line with a connection device connected to a wired line, and controlling the connection to another connection device by an instruction from the control unit. A wireless communication terminal that connects to a connection device; a storage unit that stores identification information for identifying the connection device; and a storage control unit that stores identification information of the connection device connected via a wireless line in the storage unit. A wireless communication terminal comprising a connection unit for connecting to a connection device corresponding to the identification information stored in the storage unit. 7. The communication device according to claim 6, further comprising a notifying unit for notifying when the connection unit is connected to a connection device corresponding to the identification information stored in the storage unit. The wireless communication terminal as described in the above.