JP2000101680A - Radio communication equipment, communication speed control method and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication equipment, a communication speed control method and storing medium which realizes a data communication/voice communication service at an optimal communication speed according to the quality of a radio line and utilizing a battery being the finite source for a portable radio terminal equipment by preventing operation at an unnecessarily high communication speed. SOLUTION: The equipment/method/medium is provided with an error rate detecting means 153 detecting an error rate based on the number of frames, where the judging result of an error correcting code included in received frames, and the number of the received frames, and a communication speed selecting means 152 selecting a communication speed from a communication speed selecting table based on the error rate detected by the means 153.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio communication device, a communication speed control method, and a storage medium. More particularly, the present invention relates to a radio communication speed selectable from a plurality of specified values.
In a variable communication speed wireless terminal device accommodated in a wireless communication system (such as a broadband CDMA mobile communication system) that requires higher transmission power in order to obtain good wireless channel quality, the communication speed of the communication device in consideration of power consumption is reduced. The present invention relates to a wireless communication device, a communication speed control method, and a storage medium suitable for performing setting / change.

[0002]

2. Description of the Related Art Conventionally, a PDC (Personal Di) has been developed.
digital Cellular: PHS (Personal Handy-pho)
ne System: TDMA (Time Division Multiple) represented by a simplified type mobile phone
In a wireless communication system such as a le Access (time-division multiple access) type mobile communication system, the transmission output on the wireless terminal side is controlled because the idea is that the received electric field strength on the base station side should exceed a reference value. There was no provision for doing so. Also, the communication speed was constant regardless of the quality of the wireless communication line.

[0003] In the above-mentioned radio communication system, a radio line with a high communication speed requires better radio line quality than a radio line with a low communication speed. Further, only the reception electric field strength is used for the determination of the radio channel quality, and it is general that larger transmission power is required to obtain good radio channel quality.

[0004]

However, in the above conventional example, since the communication speed is constant, the communication speed cannot be reduced even when the quality of the wireless communication line is poor, causing noise in a call or an error during data communication. There was a problem that occurred. Further, since the transmission power is constant, there is a problem that constant power is always consumed even when the quality of the wireless communication line is poor.

In recent years, wideband CDMA (W-CDM)
A) There is a difference in required communication line quality depending on the communication speed provided by a wireless line, such as mobile communication, and a wireless communication system capable of selecting the communication speed is emerging. is there.

[0006] However, in the case of this type of wireless communication system, the required wireless channel quality increases as the communication speed increases. For this reason, when the wireless channel quality is deteriorated due to the movement of the wireless terminal device or the like, in order to maintain the communication speed, the transmission output is increased on the wireless terminal side, and the wireless channel quality, that is, the electric field strength on the receiving side is increased. There is a need.

In the case of a portable wireless terminal device, a power source (battery) for operating the device is a finite resource, and an increase in transmission output consumes the battery and leads to a reduction in the operable time of the device.

The present invention has been made in view of the above points, and realizes a data communication / voice communication service at an optimum communication speed according to the quality of a wireless channel, and realizes an unnecessarily high communication speed. An object of the present invention is to provide a wireless communication device, a communication speed control method, and a storage medium that prevent operation and enable use of a battery, which is a finite resource of a portable wireless terminal device, according to wireless line quality. .

[0009]

To achieve the above object, according to the present invention, there is provided a radio communication apparatus capable of discriminating the presence or absence of a reception error, comprising an error correction code included in a reception frame. And a communication rate determining means for determining a communication rate based on the error rate detected by the error rate detecting means.

To achieve the above object, according to the present invention, the error rate detecting means detects an error rate based on the number of frames and the number of received frames for which an error correction code determination result is not possible. It is characterized by the following.

According to a third aspect of the present invention, the communication speed determining means selects a communication speed from a communication speed selection table based on an error rate detected by the error rate detecting means. It is characterized by.

According to a fourth aspect of the present invention, in order to achieve the above object, the communication speed determining means continuously varies the communication speed based on the error rate detected by the error rate detecting means. And

[0013] To achieve the above object, the present invention according to claim 5 is characterized in that wireless communication corresponding to a wideband CDMA mobile communication system is performed.

In order to achieve the above object, the present invention according to claim 6 is characterized in that wireless communication corresponding to a narrowband CDMA mobile communication system is performed.

According to another aspect of the present invention, there is provided a communication speed control method applied to a wireless communication apparatus capable of determining the presence or absence of a reception error. An error rate detecting step for detecting an error rate based on a result of the determination of the correction code, and a communication speed determining step for determining a communication speed based on the error rate detected in the error rate detecting step.

In order to achieve the above object, according to the present invention, in the error rate detecting step, the error rate is detected based on the number of frames and the number of received frames for which an error correction code determination result is not possible. It is characterized by the following.

According to a ninth aspect of the present invention, in the communication speed determining step, the communication speed is selected from a communication speed selection table based on the error rate detected in the error rate detecting step. It is characterized by.

In order to achieve the above object, according to the present invention, in the communication speed determining step, the communication speed is continuously varied based on the error rate detected in the error rate detecting step. And

In order to achieve the above object, the present invention according to claim 11 is characterized in that it is applicable to a radio communication apparatus for performing radio communication corresponding to a wideband CDMA mobile communication system.

In order to achieve the above object, the present invention according to claim 12 is characterized in that the present invention is applicable to a radio communication apparatus for performing radio communication corresponding to a narrowband CDMA mobile communication system.

In order to achieve the above object, the present invention according to claim 13 reads out by a computer storing a program for executing a communication speed control method applied to a wireless communication apparatus capable of determining the presence or absence of a reception error. A storage medium capable of detecting an error rate based on a determination result of an error correction code included in a received frame, and an error rate detected in the error rate detection step. And a communication speed determining step of determining a communication speed based on the communication speed.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

As an embodiment of the present invention, a broadband CDM
1 shows an example of a portable wireless terminal device for an A (W-CDMA) mobile communication system.

FIG. 2 shows a W-CD according to an embodiment of the present invention.
FIG. 2 is a conceptual diagram illustrating a configuration of an MA mobile communication system.
The W-CDMA mobile communication system according to the embodiment of the present invention includes a communication speed variable wireless communication terminal device 21, a wireless base station 22A, a wireless base station 22B, a wireless control device 23,
ISDN (Integrated ServicesD)
digital Network) 24, ATM (Asy)
nchronous Transfer Mode) 2
5. LAN (Local Area Network) 2
6 and so on. In the figure, 20A and 20B indicate notification signals. Note that the system configuration shown in FIG. 2 is an example and is not limited to the illustrated configuration.

The configuration of each of the above components will be described in detail. The variable communication speed wireless communication terminal device 21 is a wireless communication terminal device having a variable communication speed to which the present invention is applied, and a wireless communication terminal device via a wireless base station 22A. Perform communication. The wireless base station 22A and the wireless base station 22B manage connection between a wireless communication line and a wired communication line. The wireless control device 23 includes a wireless base station 22A,
2B connected wired communication line and existing communication network (ISD
N24, ATM 25, LAN 26, etc.), and routes a communication path with the wireless communication terminal device. The broadcast signals 20A and 20B regularly transmit information essential for system control, such as the communication carrier to which the radio base stations 22A and 22B provide the service, the identification information of the radio base station of the signal transmission source, and the like. Signal.

FIG. 3 shows a W-CD according to an embodiment of the present invention.
FIG. 4 is an explanatory diagram showing an information format of broadcast signals 20A and 20B of the MA mobile communication system. On the air slot, the broadcast signal is divided into two radio frames 37a and 37b.
, And are decoded by baseband processing on the wireless communication terminal device side, and the contents indicated by 31 to 36 are read out.

Reference numeral 31 denotes information indicating the type of the broadcast signal, 32 denotes the transmission power of the base station of the broadcast signal, 33 denotes the information frame number added cyclically, and 34 denotes the information on the receiving side of the base station. Interference information, 35 is an information element detailed area for transmitting identification information of a communication carrier or a radio base station or various information necessary for system control, and 36 is an error correction for detecting and correcting an error in the decoding. Sign.

FIG. 1 shows a W-CD according to an embodiment of the present invention.
FIG. 2 is a functional block diagram illustrating a configuration of a variable communication speed wireless communication terminal device of the MA mobile communication system. The variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention includes a radio unit 11, a baseband processing unit 12, a frame disassembly unit 13, a communication application 14, And a control unit 15. Further, the control unit 15 includes a communication control processing unit 151,
Communication speed selection means 152 and ECC error counter 15
3a, and an error rate detection means 153 having a reception frame counter 153b.

The structure of each unit will be described in detail.
Manages transmission and reception of radio waves. The baseband processing unit 12
Controls modulation and demodulation. The frame disassembly / assembly unit 13 manages disassembly / assembly of transmission / reception data in units of frames. The communication application 14 is various communication applications that make a wireless line connection request, which will be described later. The control unit 15 controls the wireless communication and the communication application 14, and executes processing shown in flowcharts of FIGS. 4 and 5 described later.

The communication control processing means 151 of the control unit 15
Perform communication control processing. Communication speed selection means 1 of control unit 15
52 selects a predetermined communication speed. The error rate detecting means 153 of the control unit 15 detects an error rate, and uses an error correction code (ECC: Error Corr).
There is an ECC error counter 153a for storing the number of NGs for determining (Recoding Code) determination, and a reception frame counter 153b for storing the number of received frames.

The correspondence between the components in the claims and the components in the variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention is as follows. is there. The error rate detecting means corresponds to the error rate detecting means 153, and the communication speed determining means corresponds to the communication speed selecting means 152.

Next, when setting a wireless channel by a trigger from a variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention configured as described above, The process for selecting the communication speed requested in the above will be described with reference to FIGS.

FIGS. 4 and 5 are flowcharts showing a communication speed selection process in the variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention. FIG. 6 is a diagram showing a W- according to an embodiment of the present invention.
FIG. 3 is an explanatory diagram showing an information format of a broadcast signal of the CDMA mobile communication system. In the figure, 61a and 61b denote radio frames, 62a to 62p denote time slots, 63 denotes synchronization pull-in information, 64 denotes power control information, and 65 denotes a logical channel information area. FIG. 7 is an explanatory diagram showing a communication speed selection table in the variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention. The communication speed in the communication speed selection table is an example, and is not limited to the illustrated values.

The control unit 15 that has received the wireless line connection request from the communication application 14 or the like starts this processing before starting the wireless line connection sequence. First, the notification signals 20A and 20B that the connection target wireless base stations 22A and 22B are constantly transmitting are received (step S40).
1). The validity of the received broadcast signal is determined by an operation using the error correction code 36 (step S402), and if there is an error in the reception, it is determined whether the error is a predetermined number of consecutive errors (step S410). ).

If the error is within the specified number of times in step S410, the notification signal is received again (step S4).
01), if the number of errors has reached the specified number in step S410, the line setting disabled status is set (step S411), and the process ends. If the line setting disabled status is set, it is determined that the radio line quality is poor, and the radio line connection sequence is not activated. On the other hand, if there is no error in the reception in step S402, the wireless line connection sequence is started. This causes a transition to the communication phase (step S403), and the connection state of the wireless line is established. On the air slot, a communication channel having the signal format of FIG. 6 is transmitted and received.

The following processing is started every time a radio frame of 10 ms is received. When the radio frame is received, the reception frame counter 153b of the error rate detection means 153 of the control unit 15 is incremented (step S40).
4) Further, the validity of the received communication channel is determined by an operation using the error correction code 36 (step S40).
5) If NG, the ECC error counter 153a is incremented (step S406). Next, it is determined whether the number of received frames has reached the specified number (Step S).
407).

If the number of received frames is equal to or smaller than the specified number in step S407, one processing unit of this processing is terminated. If the number of received frames has reached the specified number in step S407, the communication speed selection unit 152 of the control unit 15
With reference to the value of the error counter 153a, a communication speed specified by the number of errors is selected according to the communication speed selection table of FIG. 7 (step S408). For example, if the number of errors is equal to or less than a, a maximum speed of 2 Mbps is selected. Thereafter, the ECC error counter 153a and the reception frame counter 153b are reset (step S4).
09), one processing unit of this processing ends.

As described above, according to the embodiment of the present invention, a service zone is formed by a plurality of radio cells formed by a plurality of radio base stations connected to a wired communication network, and a service zone is formed in the service zone. Make a wireless connection with an existing wireless terminal, and after the wireless line connection, instruct the wireless terminal being connected to the line to control the transmission power of the wireless terminal from the wireless base station using the additional information of the communication channel. The communication speed of the formed wireless channel can be selected from a plurality of specified values, and the W-CDMA mobile communication system requires a large transmission power to obtain good wireless channel quality. In the wireless communication terminal device with variable communication speed, the error rate is determined based on the number of frames in which the determination result of the error correction code included in the received frame is NG and the number of received frames. Error rate detection means 15 for detecting
3 and the communication speed selection means 152 for selecting the communication speed from the communication speed selection table based on the error rate detected by the error rate detection means 153, the following operations and effects are obtained.

When the number of received frames has reached the specified number, the communication speed selection means 152 of the control unit 15 of the communication speed variable type wireless communication terminal device refers to the value of the ECC error counter 153a and checks the error in the communication speed selection table. Select the communication speed specified by the number of times. That is, from the received electric field strength of the signal from the wireless base station, a combination of the communication speed and the required power consumption for performing communication in the current situation is calculated,
The communication speed is determined according to a desired condition (error rate value) stored in the wireless communication terminal device.

Therefore, in the embodiment of the present invention,
By measuring the error rate of the received frames, it is possible to realize data communication / voice communication services at the optimum communication speed according to the quality of the wireless link, and to prevent operation at unnecessary high communication speeds. There is an effect that the battery, which is a finite resource of the wireless terminal device, can be used according to the quality of the wireless channel.

In addition to the above-described embodiment of the present invention, the following other embodiments can be considered.

In the above embodiment, the communication speed can be selected from a plurality of specified values, and a wireless line with a high communication speed requires better wireless line quality than a wireless line with a low communication speed. Wideband CDMA is an example of a variable communication speed wireless communication terminal device for a wireless communication system.
Although an example of a portable wireless terminal device for a (W-CDMA) mobile communication system has been described, a portable wireless terminal device of a system (such as a narrow band CDMA mobile communication system) using another similar communication medium has been described. This is also effective for selecting and changing the communication speed.

In the above-described embodiment, the communication speed can be selected from a plurality of specified values. However, it is also effective that the communication speed can be continuously varied depending on the value of the error rate.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. A storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or an apparatus, and a computer (or CPU or MPU) of the system or the apparatus executes the program code stored in the storage medium. Needless to say, this can also be achieved by executing the reading.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program code, not only the functions of the above-described embodiment are realized, but also the OS or the like running on the computer is actually executed based on the instructions of the program code. It goes without saying that a part or all of the above-described processing is performed, and the functions of the above-described embodiments are realized by the processing.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0049]

As described above, according to the radio communication apparatus of the first aspect of the present invention, a radio communication apparatus capable of determining the presence or absence of a reception error is provided. Since there are an error rate detecting means for detecting an error rate based on the result of the determination and a communication speed determining means for determining a communication speed based on the error rate detected by the error rate detecting means, the following effects are obtained. An error rate is detected based on the determination result of the error correction code included in the received frame, and a communication speed is determined based on the detected error rate, so that data communication / speech communication at an optimum communication speed according to wireless channel quality is performed. Realizes services and prevents operation at unnecessarily high communication speeds, and uses the battery, which is a finite resource of wireless communication devices (wireless communication devices such as portable wireless terminal devices), according to the quality of the wireless line. There is an effect that can be performed.

According to the second aspect of the present invention, the error rate detecting means detects the error rate based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible. The following effects are obtained. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible, and the communication speed is determined based on the detected error rate. A battery, which is a finite resource of a wireless communication device (a wireless communication device such as a portable wireless terminal device), is provided by realizing a data communication / voice communication service and preventing operation at an unnecessarily high communication speed. There is an effect that it can be used according to the quality.

According to the wireless communication apparatus of the present invention, the communication speed determining means selects the communication speed from the communication speed selection table based on the error rate detected by the error rate detecting means. The effect is as follows. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible. A wireless communication device (a wireless communication device such as a portable wireless terminal device) that realizes a data communication / voice communication service at a high communication speed and prevents operation at an unnecessarily high communication speed.
There is an effect that the battery, which is a finite resource, can be used according to the quality of the wireless channel.

According to the wireless communication apparatus of the present invention, the communication speed determining means continuously varies the communication speed based on the error rate detected by the error rate detecting means. Effect. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible, and the communication speed is continuously varied based on the detected error rate, so that the optimum communication according to the radio channel quality A battery which is a finite resource of a wireless communication device (a wireless communication device such as a portable wireless terminal device) by realizing a data communication / voice communication service at a high speed and preventing operation at an unnecessarily high communication speed. There is an effect that it is possible to use the communication according to the radio line quality.

According to the wireless communication apparatus of the present invention, since the wireless communication corresponding to the wideband CDMA mobile communication system is performed, the following effects are obtained. In a wireless communication device that performs wireless communication corresponding to a broadband CDMA mobile communication system, a data communication / voice communication service at an optimum communication speed according to wireless channel quality is realized, and an unnecessarily high communication speed is used. There is an effect that it is possible to prevent the operation and use the battery, which is a finite resource of the wireless communication device (portable wireless terminal device), according to the quality of the wireless channel.

According to the wireless communication apparatus of the present invention, since the wireless communication corresponding to the narrow band CDMA mobile communication system is performed, the following effects are obtained. In a wireless communication device that performs wireless communication corresponding to a narrowband CDMA mobile communication system, a data communication / voice communication service at an optimum communication speed according to wireless channel quality is realized, and an unnecessarily high communication speed is used. There is an effect that it is possible to use the battery which is a finite resource of the wireless communication device (portable wireless terminal device) according to the quality of the wireless line by preventing the operation of the wireless communication device.

According to the communication speed control method of the present invention, a communication speed control method applied to a wireless communication device capable of determining whether or not there is a reception error, wherein an error correction included in a received frame is performed. An error rate detection step of detecting an error rate based on the determination result of the code, and a communication speed determination step of determining a communication speed based on the error rate detected in the error rate detection step,
The following effects are obtained. An error rate is detected based on the determination result of the error correction code included in the received frame, and a communication speed is determined based on the detected error rate, so that data communication / speech communication at an optimum communication speed according to wireless channel quality is performed. Realizes services and prevents operation at unnecessarily high communication speeds, and uses the battery, which is a finite resource of wireless communication devices (wireless communication devices such as portable wireless terminal devices), according to the quality of the wireless line. There is an effect that can be performed.

According to the communication rate control method of the present invention, in the error rate detecting step, the error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible. The following effects are obtained. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible, and the communication speed is determined based on the detected error rate. A battery, which is a finite resource of a wireless communication device (a wireless communication device such as a portable wireless terminal device), is provided by realizing a data communication / voice communication service and preventing operation at an unnecessarily high communication speed. There is an effect that it can be used according to the quality.

According to the communication speed control method of the present invention, in the communication speed determination step, a communication speed is selected from a communication speed selection table based on the error rate detected in the error rate detection step. The following effects are obtained. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible. Realizing data communication / voice communication service at high communication speed and preventing operation at unnecessarily high communication speed by using limited resources of wireless communication devices (wireless communication devices such as portable wireless terminal devices). There is an effect that a certain battery can be used according to the quality of the wireless line.

According to the communication speed control method of the present invention, in the communication speed determining step, the communication speed is continuously varied based on the error rate detected in the error rate detecting step. It has the following effects. The error rate is detected based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible, and the communication speed is continuously varied based on the detected error rate, so that the optimum communication according to the radio channel quality A battery which is a finite resource of a wireless communication device (a wireless communication device such as a portable wireless terminal device) by realizing a data communication / voice communication service at a high speed and preventing operation at an unnecessarily high communication speed. There is an effect that it is possible to use the communication according to the radio line quality.

According to the communication speed control method of the present invention, it is possible to apply the present invention to a wireless communication device that performs wireless communication corresponding to a wideband CDMA mobile communication system, and thus has the following effects. In a wireless communication device that performs wireless communication corresponding to a broadband CDMA mobile communication system, a data communication / voice communication service at an optimum communication speed according to wireless channel quality is realized, and an unnecessarily high communication speed is used. There is an effect that it is possible to prevent the operation and use the battery, which is a finite resource of the wireless communication device (portable wireless terminal device), according to the quality of the wireless channel.

According to the communication speed control method of the twelfth aspect of the present invention, since it can be applied to a wireless communication device that performs wireless communication corresponding to a narrowband CDMA mobile communication system, the following effects are obtained. . In a wireless communication device that performs wireless communication corresponding to a narrowband CDMA mobile communication system, a data communication / voice communication service at an optimum communication speed according to wireless channel quality is realized, and an unnecessarily high communication speed is used. There is an effect that it is possible to use the battery which is a finite resource of the wireless communication device (portable wireless terminal device) according to the quality of the wireless line by preventing the operation of the wireless communication device.

According to the storage medium of the thirteenth aspect of the present invention, a computer-readable storage medium storing a program for executing a communication speed control method applied to a wireless communication apparatus capable of determining the presence or absence of a reception error. A medium, the communication rate control method comprising: an error rate detection step of detecting an error rate based on a determination result of an error correction code included in a received frame; and a communication rate control based on the error rate detected in the error rate detection step. And a communication speed determining step of determining the communication speed. An error rate is detected based on the determination result of the error correction code included in the received frame, and a communication speed is determined based on the detected error rate, so that data communication / speech communication at an optimum communication speed according to wireless channel quality is performed. Realizes services and prevents operation at unnecessarily high communication speeds, and uses the battery, which is a finite resource of wireless communication devices (wireless communication devices such as portable wireless terminal devices), according to the quality of the wireless line. There is an effect that can be performed.

[Brief description of the drawings]

FIG. 1 is a functional block diagram showing a configuration of a variable communication speed wireless communication terminal device of a W-CDMA mobile communication system according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a configuration of a W-CDMA mobile communication system according to an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing an information format of a broadcast signal of the W-CDMA mobile communication system according to the embodiment of the present invention.

FIG. 4 is a flowchart showing a communication speed selection process in a variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention.

FIG. 5 is a flowchart showing a communication speed selection process in the variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention.

FIG. 6 is an explanatory diagram showing an information format of a broadcast signal in the W-CDMA mobile communication system according to the embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a communication speed selection table in the variable communication speed wireless communication terminal device of the W-CDMA mobile communication system according to the embodiment of the present invention.

[Description of Signs] 15 Control unit 152 Communication speed selection unit 153 Error rate detection unit 153a ECC error counter 153b Received frame counter

Claims (13)

[Claims] 1. A wireless communication device capable of determining the presence or absence of a reception error, comprising: an error rate detection means for detecting an error rate based on a determination result of an error correction code included in a received frame; And a communication speed determining means for determining a communication speed based on the error rate detected in the step (c). 2. The wireless communication apparatus according to claim 1, wherein said error rate detection means detects an error rate based on the number of frames and the number of received frames for which the determination result of the error correction code is not possible. 3. The wireless communication apparatus according to claim 1, wherein said communication speed determining means selects a communication speed from a communication speed selection table based on an error rate detected by said error rate detecting means. 4. The wireless communication apparatus according to claim 1, wherein said communication speed determining means continuously varies the communication speed based on an error rate detected by said error rate detecting means. 5. The wireless communication device according to claim 1, wherein the wireless communication device performs wireless communication corresponding to a broadband CDMA mobile communication system. 6. The wireless communication apparatus according to claim 1, wherein the wireless communication apparatus performs wireless communication corresponding to a narrowband CDMA mobile communication system. 7. A communication rate control method applied to a wireless communication device capable of determining the presence or absence of a reception error, the method comprising detecting an error rate based on a determination result of an error correction code included in a received frame. And a communication speed determination step of determining a communication speed based on the error rate detected in the error rate detection step. 8. The communication speed control method according to claim 7, wherein in the error rate detecting step, an error rate is detected based on the number of frames and the number of received frames for which an error correction code determination result is not possible. 9. The communication speed control method according to claim 7, wherein in the communication speed determination step, a communication speed is selected from a communication speed selection table based on the error rate detected in the error rate detection step. . 10. The communication speed control method according to claim 7, wherein in the communication speed determination step, the communication speed is continuously varied based on the error rate detected in the error rate detection step. 11. The communication speed control method according to claim 7, wherein the communication speed control method is applicable to a wireless communication device that performs wireless communication corresponding to a broadband CDMA mobile communication system. 12. The communication speed control method according to claim 7, wherein the communication speed control method is applicable to a wireless communication device that performs wireless communication corresponding to a narrowband CDMA mobile communication system. 13. A computer-readable storage medium storing a program for executing a communication speed control method applied to a wireless communication device capable of determining the presence or absence of a reception error, the communication speed control method comprising: An error rate detection step of detecting an error rate based on a determination result of an error correction code included in a received frame, and a communication rate determination step of determining a communication rate based on the error rate detected in the error rate detection step. Characteristic storage medium.