JP2008288954A - Radio communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication apparatus capable of suppressing transmission power in accordance with receiving sensitivity regardless of the existence of an operation through an inputting and outputting part when a radio wave state is satisfactory. <P>SOLUTION: An operation processing part automatically adjusts transmission power to an optimum value in accordance with receiving sensitivity occasionally acquired from a radio transmitting and receiving part connected to an antenna part. A conversion table for obtaining optimum transmission power corresponding to the receiving sensitivity from the receiving sensitivity is stored in a main storing part that can be read from the operation reading part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wireless communication device, and more particularly to an electric power saving method in a wireless communication device capable of adjusting transmission power.

  As a technique related to the present invention, a method for reducing power consumption of a wireless communication device is known. However, in any case, the power consumption is reduced when the wireless communication device is not in operation, such as intermittent communication during standby, no communication outside the radio wave coverage area, or long-term no operation.

FIG. 1 is a block diagram of a wireless communication apparatus in the related technology.
The wireless communication apparatus in the related technology includes an antenna unit 1, a wireless transmission / reception unit 2, a wireless control unit 3, an arithmetic processing unit 4, a main storage unit 5, a power supply unit 6, and an input / output unit 7. To do.

  The antenna unit 1 is connected to the wireless transmission / reception unit 2. The wireless transmission / reception unit 2 is further connected to a wireless control unit 3. The wireless control unit 3 is further connected to the arithmetic processing unit 4. The arithmetic processing unit 4 is further connected to a main storage unit 5 and an input / output unit 7. The power supply unit 6 is connected to the wireless transmission / reception unit 2 and the wireless control unit 3. Although not particularly illustrated, the power supply unit 6 may be further connected to the arithmetic processing unit 4, the main storage unit 5, the input / output unit 7, and the like.

  The radio transmission / reception unit 2 transmits / receives data to / from the antenna unit 1 in accordance with the timing signal input from the radio control unit 3, and also amplifies the reception signal. The wireless control unit 3 generates a data transmission / reception timing signal according to the setting input from the arithmetic processing unit 4 and transmits the data transmission / reception timing signal to the wireless transmission / reception unit 2, and performs transmission / reception and control of data to / from the wireless transmission / reception unit. The arithmetic processing unit 4 reads and writes data from and to the main storage unit 5 and executes programs for realizing each function of the wireless communication device. The main storage unit 5 stores data necessary for the arithmetic processing unit 4 to execute the program. The power supply unit 6 supplies power to the wireless transmission / reception unit 2 and the wireless control unit 3. Although not particularly illustrated, the power supply unit 6 may supply power to the arithmetic processing unit 4 and the main storage unit 5.

  The wireless communication apparatus according to the related technology may implement the following measures for power saving in an environment where radio wave conditions are getting worse. That is, the arithmetic processing unit 4 extends the wireless communication interval or temporarily stops the wireless communication itself according to the reception information obtained from the wireless transmission / reception unit 2 via the wireless control unit 3. Further, when a preset time elapses with no change in the input from the input / output unit 7, the operation of the arithmetic processing unit 4 is stopped.

In relation to the above, Patent Document 1 (Japanese Patent Laid-Open No. 58-139536) discloses an invention relating to a transmission power control apparatus.
The transmission power control device of the invention of Patent Document 1 is a satellite communication relay device or various wireless transmissions equipped with a transmission / reception system device of a plurality of systems including a reception system including an intermediate frequency amplifier and a transmission system including a transmission power amplifier and the like. It is the transmission power control apparatus in the system relay apparatus. The transmission power control apparatus shares a high-voltage power supply circuit for a plurality of transmission power amplifiers. The transmission power control device includes a monitor circuit, an identification circuit, a designation circuit, and a control circuit. Here, the monitor circuit monitors the received power of each intermediate frequency amplifier. The discriminating circuit discriminates the strength of received power of each receiving system based on the monitor information of each monitor circuit and determines the output power of the corresponding transmission power amplifier. The designation circuit determines a supply voltage value to each transmission power amplifier according to an instruction from the identification circuit. The control circuit controls the supply voltage from the high-voltage power supply circuit to each transmission power amplifier according to an instruction from the designation circuit.

Patent Document 2 (Japanese Patent Laid-Open No. 1-105624) discloses an invention relating to a wireless transmission / reception apparatus with transmission output control.
The wireless transmission / reception apparatus with transmission output control of the invention of Patent Document 2 is a portable and portable simplex wireless transmission / reception apparatus using a single frequency and incorporating a battery. It has monitoring means and transmission output reduction means. Here, the monitoring means monitors the electric field level at the time of reception. The transmission means reducing means decreases the transmission output during transmission when the monitoring means determines that there is an electric field level above a certain level. The wireless transmission / reception apparatus with transmission output control reduces power consumption and extends the use time of a call in near field communication.

Patent Document 3 (Japanese Patent Laid-Open No. 10-84312) discloses an invention relating to a mobile radio telephone.
The mobile radiotelephone of the invention of Patent Document 3 is connected to a base station via a radio line. In addition, a wireless reception unit, a reception electric field strength detection unit, a wireless transmission unit, a transmission output reduction control unit, and a notification unit are provided. Here, the wireless receiving means receives a wireless signal from the base station. The received electric field strength detecting means detects the received electric field strength of the radio signal from the base station. The wireless transmission means transmits a wireless signal to the base station. The transmission output reduction control means operates when the reception electric field strength of the radio signal from the base station detected by the reception electric field strength detection means is stronger than a predetermined value, and the radio signal transmitted from the radio transmission means to the base station Reduce the transmission output of. The notification means notifies the operation state of the transmission output reduction control means.

Patent Document 4 (Japanese Patent Laid-Open No. 2005-12308) discloses an invention related to a power saving device.
The power saving device of the invention of Patent Document 4 includes wireless communication means, received electric field strength detection means, movement detection means, power supply means, and control means. Here, the wireless communication means performs wireless communication with the base station. The received electric field strength detecting means detects the received electric field strength of information from the base station received by the wireless communication means. The movement detection means detects the movement of the device provided with the power saving device. The power supply means supplies power to at least the wireless communication means and the movement detection means. When the received electric field strength of the information detected by the received electric field strength detecting means is not more than a predetermined level and the movement detecting device does not detect the movement of the device provided with the power saving device, at least wireless communication is performed. The power supply means is controlled so as to stop the power supplied to the means, and when the movement of the device is detected by the movement detection means, the power supply is resumed to the wireless communication means for which the power supply has been stopped. Thus, the power supply means is controlled.

Patent Document 5 (Japanese Patent Application Laid-Open No. 2006-345363) discloses an invention relating to a wireless communication apparatus.
The wireless communication device of the invention of Patent Document 5 is a wireless communication device that adaptively controls the modulation method and coding rate of the data channel based on the received channel state information. In addition, a first data table, a second data table, a first means, a second means, a third means, and a fourth means are provided. Here, the first data table represents the correspondence between the channel state information, the modulation scheme, and the coding rate. The second data table represents the correspondence between the channel state information and the transmission power of the control channel. The first means receives channel state information from the communication partner. The second means accesses the first data table and selects the modulation method and coding rate of the data channel corresponding to the received channel state information. The third means accesses the second data table and selects the transmission power of the control channel corresponding to the received channel state information. The fourth means transmits the data channel with the selected modulation scheme and coding rate, and transmits the control channel based on the selected transmission power.

JP 58-139536 A JP-A-1-105624 Japanese Patent Laid-Open No. 10-84312 JP 2005-12308 A JP 2006-345363 A

  The measures for power saving in the wireless communication apparatus in the related technology described above will cause a decrease in function as a wireless communication service in order to extend the interval of wireless communication or temporarily stop wireless communication. . Therefore, it is not suitable for implementation when the reception sensitivity is good. Moreover, the power saving measure based on the input change from the input / output unit 7 requires an external start operation. Therefore, it is not suitable for implementation when there is no external input.

An object of the present invention is to provide a wireless communication device capable of suppressing transmission power in accordance with reception sensitivity regardless of the presence or absence of an external start operation when the radio wave condition is good.
Another object of the present invention is to provide a wireless communication method capable of suppressing transmission power in accordance with reception sensitivity regardless of the presence or absence of an external start operation when the radio communication device has a good radio wave condition. is there.

  Hereinafter, means for solving the problem will be described using the numbers used in (Best Mode for Carrying Out the Invention). These numbers are added to clarify the correspondence between the description of (Claims) and (Best Mode for Carrying Out the Invention). However, these numbers should not be used to interpret the technical scope of the invention described in (Claims).

A wireless communication apparatus according to the present invention includes an antenna unit, a wireless transmission / reception unit, a wireless control unit, an arithmetic processing unit, a main storage unit, and a power supply unit. Here, the wireless transmission / reception unit is connected to the antenna unit, and performs transmission / reception and amplification of communication data. The wireless control unit generates a timing signal for the wireless transmission / reception unit to transmit / receive communication data, and acquires reception sensitivity information from the wireless transmission / reception unit. The arithmetic processing unit executes the wireless communication program and monitors the wireless control unit. The main storage unit stores data necessary for the arithmetic processing unit to execute the wireless communication program. The power supply unit supplies power to the wireless transmission / reception unit and the wireless control unit.
The main storage unit also includes a conversion table. Here, the conversion table is used for adjusting the transmission power consumed by the wireless transmission / reception unit in response to a change in reception sensitivity.

  In the wireless communication apparatus of the present invention, the conversion table includes a portion in which transmission power continuously decreases as reception sensitivity increases.

  In the wireless communication apparatus of the present invention, the reception sensitivity has a plurality of ranges. In each of a plurality of ranges of reception sensitivity, transmission power is a linear function based on reception sensitivity. The conversion table has three columns. The first column stores a plurality of threshold values that divide the reception sensitivity into a plurality of ranges. The second column stores a numerical value corresponding to the slope coefficient of the linear function for each of the plurality of bands. The third column stores numerical values corresponding to the intercept coordinates of the linear function for each of the plurality of bands.

  In the wireless communication apparatus of the present invention, the conversion table relates to correspondence between reception sensitivity and transmission power. The arithmetic processing unit receives the reception sensitivity, refers to the conversion table, and outputs a transmission power value.

  In the wireless communication apparatus of the present invention, the wireless control unit receives the value of the transmission power from the arithmetic processing unit and controls the wireless transmission / reception unit so as to output the transmission power corresponding to the input value.

  In the wireless communication apparatus of the present invention, the conversion table relates to correspondence between reception sensitivity and wireless transmission / reception unit voltage. The arithmetic processing unit receives the reception sensitivity, refers to the conversion table, and outputs the voltage value of the wireless transmission / reception unit.

  In the wireless communication apparatus of the present invention, the power supply unit receives the value of the wireless transmission / reception unit voltage from the arithmetic processing unit and supplies the voltage corresponding to the input value to the wireless transmission / reception unit.

  In the wireless communication method of the present invention, (a) the wireless communication device suppresses transmission power according to reception sensitivity when the radio wave condition is good, and (b) the wireless transmission / reception unit of the wireless communication device receives the signal. Monitoring the sensitivity, (c) the arithmetic processing unit of the wireless communication device determines the value of the transmission power corresponding to the reception sensitivity, and (d) the transmission power of the wireless communication device is changed. It comprises.

  In the wireless communication method of the present invention, the step (b) includes (b-1) setting the transmission power to a predetermined initial value when the reception sensitivity is less than a predetermined threshold; ) When the reception sensitivity is equal to or higher than a predetermined threshold, the wireless transmission / reception unit outputs the reception sensitivity.

  In the wireless communication method of the present invention, the step (c) includes (c-1) a conversion table for the main storage unit to obtain an output voltage set in the wireless transmission / reception unit according to the reception sensitivity from the reception sensitivity. (C-2) The arithmetic processing unit reads the value of the transmission power corresponding to the reception sensitivity with reference to a predetermined conversion table stored in the main storage unit of the wireless communication device. And (c-3) storing the read transmission power value in the main storage unit.

  In the wireless communication method of the present invention, in step (d), (d-1) the arithmetic processing unit controls the wireless control unit to transmit the value stored in the main storage unit, and (d-2) ) The radio control unit controls the radio transmission / reception unit to set the voltage of transmission power to a value stored in the main storage unit; and (d-3) power supplied from the power supply unit by the radio control unit Wireless transmission with a set value of power.

  In the wireless communication method of the present invention, step (c) includes (c-1 ′) a conversion table for the main storage unit to obtain an output voltage to be set in the power supply unit according to the reception sensitivity from the reception sensitivity. And (c-2 ′) the processing unit reads the value of the power supply unit output voltage corresponding to the reception sensitivity with reference to the conversion table, and (c-3 ′) The processing unit includes storing the read transmission power value in the main storage unit.

  In the wireless communication method of the present invention, in step (d), (d-1 ′) the arithmetic processing unit controls the power supply unit to set the voltage of the transmission power to a value stored in the main storage unit. , (D-2 ′) the power supply unit supplies the transmission power of the set value to the wireless transmission / reception unit, and (d-3 ′) the wireless control unit uses the power supplied from the power supply unit, Performing wireless transmission.

According to the wireless communication apparatus of the present invention, when the reception sensitivity is good, the power consumption of the wireless communication apparatus is saved by suppressing the transmission power. In addition, since the arithmetic processing unit 4 automatically adjusts the transmission power in response to a change in reception sensitivity, there is no need for the user to perform any operation via the input / output unit 7.
Similarly, according to the wireless communication method of the present invention, when the reception sensitivity is good, the power consumption of the wireless communication device is saved by suppressing the transmission power. In addition, since the arithmetic processing unit 4 automatically adjusts the transmission power in response to a change in reception sensitivity, there is no need for the user to perform any operation via the input / output unit 7.

The best mode for carrying out a wireless communication device according to the present invention will be described below with reference to the accompanying drawings.
FIG. 2 is a block diagram of a wireless communication apparatus according to the present invention. The wireless communication apparatus of the present invention can realize at least the following two types of embodiments by switching the connection relationship between the components.

(First embodiment)
FIG. 3 is a block diagram of the wireless communication apparatus according to the present embodiment.
The wireless communication apparatus of this embodiment includes an antenna unit 1, a wireless transmission / reception unit 2, a wireless control unit 3, an arithmetic processing unit 4, a main storage unit 5, a power supply unit 6, and an input / output unit 7. To do.
Here, since the antenna unit 1 and the input / output unit 7 are not related to the essence of the present invention, there are no particular limitations or conditions. Any antenna may be used for the antenna unit 1. The input / output unit 7 includes all elements other than the antenna unit 1, the wireless transmission / reception unit 2, the wireless control unit 3, the arithmetic processing unit 4, the main storage unit 5, and the power supply unit 6. For example, a display device or an operation keypad may be included.

  The antenna unit 1 is connected to the wireless transmission / reception unit 2. The wireless transmission / reception unit 2 is further connected to a wireless control unit 3. The wireless control unit 3 is further connected to the arithmetic processing unit 4. The arithmetic processing unit 4 is further connected to a main storage unit 5 and an input / output unit 7. The power supply unit 6 is connected to the wireless transmission / reception unit 2 and the wireless control unit 3. Although not particularly illustrated, the power supply unit 6 may be further connected to the arithmetic processing unit 4, the main storage unit 5, the input / output unit 7, and the like.

  The radio transmission / reception unit 2 transmits / receives data to / from the antenna unit 1 in accordance with the timing signal input from the radio control unit 3, and also amplifies the reception signal. The wireless control unit 3 generates a data transmission / reception timing signal according to the setting input from the arithmetic processing unit 4 and transmits the data transmission / reception timing signal to the wireless transmission / reception unit 2, and performs transmission / reception and control of data to / from the wireless transmission / reception unit 2. . The arithmetic processing unit 4 reads and writes data from and to the main storage unit 5 and executes programs for realizing each function of the wireless communication device. The main storage unit 5 stores data necessary for the arithmetic processing unit 4 to execute the program. The power supply unit 6 supplies power to the wireless transmission / reception unit 2 and the wireless control unit 3. Although not particularly illustrated, the power supply unit 6 may supply power to the arithmetic processing unit 4 and the main storage unit 5.

FIG. 4 is a control flow diagram of the wireless communication method in the present embodiment.
First, in step S <b> 11, the wireless control unit 3 obtains reception sensitivity from the wireless transmission / reception unit 2. The arithmetic processing unit 4 compares the reception sensitivity with the power saving threshold value a to determine whether the reception sensitivity is sufficiently good. If the reception sensitivity is greater than or equal to the power saving threshold a, it is determined that the reception sensitivity is sufficiently good, and the control flow proceeds to step S14.

  On the contrary, if the reception sensitivity is less than the power saving threshold value a, it is determined that the reception sensitivity is not sufficiently good. In this case, the control flow proceeds to step S12. In step S12, the transmission power is reset to the initial value. The initial value for transmission power is preferably set in advance at the time of industrial shipment. Thereafter, the control flow returns to step S11 and continues the loop until it is determined that the reception sensitivity is sufficiently good.

In step S <b> 13, the arithmetic processing unit 4 reads the reception sensitivity transmission power conversion table stored in the main storage unit 5.
If there is a sufficient storage capacity in the arithmetic processing unit 4, all or part of the reception sensitivity transmission power conversion table read once may reside in the arithmetic processing unit 4.

  In step S14, the arithmetic processing unit 4 refers to the reception sensitivity transmission power conversion table and derives a transmission power setting value corresponding to the reception sensitivity obtained in step S11.

  In step S15, the arithmetic processing unit 4 stores the transmission power setting value derived in step S14 in the main storage unit 5.

  In step S <b> 16, the arithmetic processing unit 4 controls the radio control unit 3 to transmit the transmission power setting value stored in the main storage unit 5 in step 15. The radio control unit 3 changes the transmission power adjustment voltage according to the transmission power setting value.

  In step S <b> 17, the transmission power adjustment voltage is reduced, whereby the power consumed by transmission performed from the wireless transmission / reception unit 2 via the antenna unit 1 is reduced.

  After step S17, the process returns to step S11 and the control flow loop is repeated.

  FIG. 5 is a diagram for comparing the power consumed by the wireless communication apparatus of the present invention with the power consumed by the wireless communication apparatus of the related technology. In connection with the step S17, the reduction of transmission power will be described.

  FIG. 5A is a diagram showing the relationship between the reception sensitivity and the transmission power corresponding to the reception sensitivity in the wireless communication apparatus of the present invention. The horizontal axis represents reception sensitivity, and the vertical axis represents transmission power. On the horizontal axis, a point a indicates a power saving threshold value a. When the reception sensitivity is less than the power saving threshold a, the transmission power is fixed to the maximum value. On the horizontal axis, the point b indicates the reception sensitivity threshold value b. When the reception sensitivity is equal to or higher than the reception sensitivity threshold b, the transmission power is fixed to the minimum value. When the reception sensitivity is greater than or equal to the power saving threshold value a and less than the reception sensitivity threshold value b, the higher the reception sensitivity, the lower the transmission power. The relationship between the reception sensitivity and the transmission power in the case where the reception sensitivity is greater than or equal to a and less than b is depicted as an oblique straight line in FIG. 5 (a), but this shape is not necessarily required. For example, as will be described later, a threshold value may be further provided between the points a and b, and the sections divided by the plurality of threshold values may be connected by lines having different shapes.

  FIG.5 (b) is a figure which shows the relationship between the reception sensitivity in the radio | wireless communication apparatus by the said related technology, and the transmission power corresponding to the reception sensitivity. The transmission power is fixed at the maximum value when the reception sensitivity is less than b with respect to the reception sensitivity threshold b, and the transmission power is fixed at the minimum value when the reception sensitivity is b or more. ing.

  FIG. 5 (c) is an overlay of FIG. 5 (a) and FIG. 5 (b). FIG.5 (c) shows the power consumption saved in the radio | wireless communication apparatus of this invention compared with the radio | wireless communication apparatus by the said related technology. In the case where the reception sensitivity is greater than or equal to the power saving threshold a and less than the reception sensitivity threshold b, the shaded portion indicates the power consumption that is saved.

FIG. 6 is a diagram illustrating a correspondence relationship between reception sensitivity and transmission power when arbitrary threshold values a ₁ , a ₂ , and a ₃ are provided between the points a and b in FIG. is there. FIG. 6 is the same as FIG. 5A when the reception sensitivity is less than a and greater than or equal to b, but is different in other cases. That is, when the reception sensitivity is a or more and less than a ₁ , when a ₁ or more and less than a ₂ , and when a ₂ or more and less than a ₃ , the reception sensitivity and the transmission power are represented by a plurality of straight lines having different slopes. The correspondence relationship is shown.

  FIG. 7 is an example of a reception sensitivity transmission power conversion table stored in the main storage unit of the wireless communication apparatus of FIG. 3 and used in step S13 of FIG. Here, the conversion table includes three columns, and the left column indicates a plurality of threshold values in reception sensitivity. The middle column shows the slope of the straight line in that section. The right column shows the intersection with the vertical axis of the straight line in that section, that is, the intercept coordinates.

FIG. 8 is a graph showing the result of calculating the transmission voltage Y from the reception sensitivity X based on the conversion table of FIG. fundamentally,
Y = AX + B
The graph of the linear function expressed by is drawn. For example, if the reception sensitivity is less than a,
Y _{= B MAX}
And
If the reception sensitivity is a or more and less than a1,
Y = A ₀ X + B ₀
Holds. Furthermore, the continuity of the output power is ensured at each of the plurality of thresholds, for example, at point a,
B _MAX = A ₀ a + B ₀
It is desirable that

  What should be noted in the wireless communication apparatus or wireless communication method of the present embodiment is that the entire wireless communication apparatus is first saved by reducing the transmission power. Next, since it is not necessary to add a component as compared with the wireless communication device according to the related technology, power saving can be realized without increasing the cost. Furthermore, the power saving of the wireless communication device is to reduce the cost because the capacity of a power source such as a battery or a battery necessary for operating the wireless communication device for the same time can be reduced. In addition, when the wireless communication device is fixedly installed, the radio wave condition is stabilized, and as a result, variation in the transmission power setting value or the wireless transmission / reception unit voltage value is suppressed, so that a stable power saving effect is obtained. That is.

(Second embodiment)
FIG. 9 is a block diagram of the wireless communication apparatus in the present embodiment.
The components of the wireless communication apparatus in the present embodiment are exactly the same as those in the first embodiment, and thus description thereof is omitted.

Since the connection relationship between the components of the wireless communication apparatus in this embodiment is substantially the same as that in the first embodiment, the description of the common parts of both embodiments will be omitted.
In this embodiment, in addition to the connection relationship in the first embodiment, the arithmetic processing unit 4 and the power supply unit 6 are also connected.

The operation of the wireless communication apparatus according to the present embodiment is the same as that of the first embodiment until halfway, but all will be described without omission for the sake of safety.
The radio transmission / reception unit 2 transmits / receives data to / from the antenna unit 1 in accordance with the timing signal input from the radio control unit 3, and also amplifies the reception signal. The wireless control unit 3 generates a data transmission / reception timing signal according to the setting input from the arithmetic processing unit 4 and transmits the data transmission / reception timing signal to the wireless transmission / reception unit 2, and performs transmission / reception and control of data to / from the wireless transmission / reception unit. The arithmetic processing unit 4 reads and writes data from and to the main storage unit 5 and executes programs for realizing each function of the wireless communication device. The main storage unit 5 stores data necessary for the arithmetic processing unit 4 to execute the program. The power supply unit 6 supplies power to the wireless transmission / reception unit 2 and the wireless control unit 3. Although not particularly illustrated, the power supply unit 6 may supply power to the arithmetic processing unit 4 and the main storage unit 5.

FIG. 10 is a control flowchart of the wireless communication method in the present embodiment.
First, in step S <b> 21, the wireless control unit 3 obtains reception sensitivity from the wireless transmission / reception unit 2. Step S21 corresponds to step S11 in the first embodiment. The arithmetic processing unit 4 compares the reception sensitivity with the power saving threshold value a to determine whether the reception sensitivity is sufficiently good. If the reception sensitivity is equal to or greater than the power saving threshold value a, it is determined that the reception sensitivity is sufficiently good, and the control flow proceeds to step S24. Step S24 corresponds to step S14 in the first embodiment.

  On the contrary, if the reception sensitivity is less than the power saving threshold value a, it is determined that the reception sensitivity is not sufficiently good. In this case, the control flow proceeds to step S22. Step S22 corresponds to step S12 in the first embodiment. In step S22, the transmission power is reset to the initial value. The initial value for transmission power is preferably set in advance at the time of industrial shipment. Thereafter, the control flow returns to step S21 and continues the loop until it is determined that the reception sensitivity is sufficiently good.

In step S <b> 23, the arithmetic processing unit 4 reads the reception sensitivity wireless transmission / reception unit voltage conversion table stored in the main storage unit 5. Step S23 corresponds to step S13 in the first embodiment.
If there is a sufficient storage capacity in the arithmetic processing unit 4, all or part of the reception sensitivity transmission power conversion table read once may reside in the arithmetic processing unit 4.

  In step S24, the arithmetic processing unit 4 refers to the reception sensitivity wireless transmission / reception unit voltage conversion table to derive a wireless transmission / reception unit voltage setting value corresponding to the reception sensitivity obtained in step S21.

  In step S <b> 25, the arithmetic processing unit 4 stores the wireless transmission / reception unit voltage setting value derived in step S <b> 24 in the main storage unit 5. Step S25 corresponds to step S15 in the first embodiment.

  In step S26, the arithmetic processing unit 4 controls the power supply unit 6 to transmit the transmission power setting value stored in the main storage unit 5 in step S25. Step S26 corresponds to step S16 in the first embodiment. The power supply unit 6 supplies power corresponding to the transmission power setting value to the wireless transmission / reception unit 2.

  In step S27, the transmission power adjustment voltage is reduced, so that the power consumed in transmission performed from the wireless transmission / reception unit 2 via the antenna unit 1 is reduced. Step S27 corresponds to step S17 in the first embodiment.

  After step S27, the process returns to step S21 and the control flow loop is repeated.

  In the present embodiment, the reduction of the voltage of the wireless transmission / reception unit is equivalent to the reduction of power consumption as a result of the wireless communication device. Therefore, the description relating to the reduction of transmission power using FIGS. 5A to 5C and FIG. 8 in the first embodiment is also applied to this embodiment as it is.

  FIG. 11 is an example of the reception sensitivity wireless transmission / reception unit voltage conversion table stored in the main storage unit of the wireless communication apparatus of FIG. 9 and used in step S23 of FIG. Here, the conversion table includes three columns, and the left column indicates a plurality of threshold values in reception sensitivity. The middle column shows the slope of the straight line in that section. The right column shows the intersection with the vertical axis of the straight line in that section, that is, the intercept coordinates.

FIG. 12 is a graph showing the result of calculating the transmission voltage Y ′ from the reception sensitivity X based on the conversion table of FIG. fundamentally,
Y '= CX + D
The graph of the linear function expressed by is drawn. For example, if the reception sensitivity is less than a,
Y _{'= D MAX}
And
If the reception sensitivity is a or more and less than a1,
Y ′ = C ₀ X + D ₀
Holds. Furthermore, the continuity of the output power is ensured at each of the plurality of thresholds, for example, at point a,
D _MAX = C ₀ a + D ₀
It is desirable that

  In common with the first embodiment and the second embodiment, the wireless communication apparatus or the wireless communication method of the present invention is particularly notable. First, by reducing the transmission power, the entire wireless communication apparatus is reduced in power consumption. Is Rukoto. Next, since it is not necessary to add a component as compared with the wireless communication device according to the related technology, power saving can be realized without increasing the cost. Furthermore, the power saving of the wireless communication device is to reduce the cost because the capacity of a power source such as a battery or a battery necessary for operating the wireless communication device for the same time can be reduced. In addition, when the wireless communication device is fixedly installed, the radio wave condition is stabilized, and as a result, variation in the transmission power setting value or the wireless transmission / reception unit voltage value is suppressed, so that a stable power saving effect is obtained. That is.

FIG. 1 is a block diagram of a wireless communication apparatus according to a technique related to the present invention. FIG. 2 is a block diagram of the wireless communication apparatus of the present invention. FIG. 3 is a block diagram of the first embodiment of the present invention. FIG. 4 is a control flow diagram of the first embodiment of the present invention. FIG. 5 is a diagram for explaining the power saving according to the present invention. FIG. 6 is a diagram illustrating an example of conversion between reception sensitivity and transmission power according to the present invention. FIG. 7 is an example of a reception sensitivity transmission power conversion table. FIG. 8 is a graph of the result of calculating the transmission voltage from the reception sensitivity based on the reception sensitivity transmission power conversion table. FIG. 9 is a block diagram of the second embodiment of the present invention. FIG. 10 is a control flow diagram of the second embodiment of the present invention. FIG. 11 is an example of a reception sensitivity wireless transmission / reception unit voltage conversion table. FIG. 12 is a graph showing the result of calculating the transmission voltage from the reception sensitivity based on the reception sensitivity wireless transmission / reception unit voltage conversion table.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna part 2 Wireless transmission / reception part 3 Wireless control part 4 Arithmetic processing part 5 Main memory part 6 Power supply part 7 Input / output part

Claims (13)

An antenna section;
A wireless transmission / reception unit connected to the antenna unit for transmitting / receiving and amplifying communication data;
A wireless control unit that generates a timing signal for the wireless transmission / reception unit to transmit / receive the communication data, and obtains reception sensitivity information from the wireless transmission / reception unit;
An arithmetic processing unit that executes a wireless communication program and monitors the wireless control unit;
A main memory for storing data necessary for the arithmetic processing unit to execute the wireless communication program;
A power supply unit that supplies power to the radio transmission / reception unit and the radio control unit;
The main storage unit
A wireless communication apparatus comprising a conversion table for adjusting transmission power consumed by the wireless transmission / reception unit in response to a change in the reception sensitivity. The wireless communication device according to claim 1,
The conversion table is
A wireless communication apparatus comprising a portion in which the transmission power continuously decreases as the reception sensitivity improves. The wireless communication device according to claim 2,
The reception sensitivity has a plurality of ranges,
In each of the plurality of ranges, the transmission power is a linear function based on the reception sensitivity,
The conversion table is
A column for storing a plurality of threshold values for dividing the reception sensitivity into the plurality of ranges;
For each of the plurality of bands, a column that stores a numerical value corresponding to the slope coefficient of the linear function;
A wireless communication device comprising: a column for storing a numerical value corresponding to an intercept coordinate of the linear function for each of the plurality of bands. In the radio | wireless communication apparatus in any one of Claims 1-3,
The conversion table relates to the correspondence between the reception sensitivity and the transmission power,
The arithmetic processing unit is a wireless communication device that receives the reception sensitivity and outputs the value of the transmission power with reference to the conversion table. In the radio | wireless communication apparatus in any one of Claims 1-4,
The wireless control unit is configured to receive the value of the transmission power from the arithmetic processing unit, and to control the wireless transmission / reception unit to output transmission power corresponding to the input value. In the radio | wireless communication apparatus in any one of Claims 1-3,
The conversion table relates to the correspondence between the reception sensitivity and the wireless transceiver voltage,
The arithmetic processing unit is a wireless communication device that receives the reception sensitivity and outputs a voltage value of the wireless transmission / reception unit with reference to the conversion table. In the radio | wireless communication apparatus in any one of Claims 1-3 or 6,
The power supply unit receives a value of the wireless transmission / reception unit voltage from the arithmetic processing unit and supplies a voltage corresponding to the input value to the wireless transmission / reception unit. (A) when the radio communication device is in a good radio wave state, suppressing transmission power according to reception sensitivity;
(B) the wireless transmission / reception unit of the wireless communication device monitors reception sensitivity;
(C) an arithmetic processing unit of the wireless communication device determines the transmission power according to the reception sensitivity;
(D) A wireless communication method comprising: changing the transmission power of the wireless communication device. The wireless communication method according to claim 8, wherein
The step (b)
(B-1) When the reception sensitivity is less than a predetermined threshold, the transmission power is set to a predetermined initial value;
(B-2) A wireless communication method comprising: when the reception sensitivity is equal to or higher than a predetermined threshold, the wireless transmission / reception unit outputs the reception sensitivity. The wireless communication method according to claim 8 or 9,
The step (c)
(C-1) The main storage unit stores in advance a conversion table for obtaining an output voltage set in the wireless transceiver according to the reception sensitivity from the reception sensitivity;
(C-2) The arithmetic processing unit reads the value of the transmission power according to the reception sensitivity with reference to a predetermined conversion table stored in the main storage unit of the wireless communication device;
(C-3) A wireless communication method comprising: the arithmetic processing unit storing the read transmission power value in the main storage unit. In the radio | wireless communication method in any one of Claims 8-10,
The step (d)
(D-1) the arithmetic processing unit controls the wireless control unit to transmit the value stored in the main storage unit;
(D-2) the wireless control unit controls the wireless transmission / reception unit to set the voltage of the transmission power to the value stored in the main storage unit;
(D-3) The radio | wireless communication method which comprises the said radio | wireless control part performing radio transmission with the electric power of the said set value among the electric power supplied from the said power supply part. The wireless communication method according to claim 8 or 9,
The step (c)
(C-1 ′) the main storage unit stores in advance a conversion table for obtaining an output voltage to be set in the power supply unit according to the reception sensitivity from the reception sensitivity;
(C-2 ′) the arithmetic processing unit reads the value of the power supply unit output voltage according to the reception sensitivity with reference to the conversion table;
(C-3 ′) A wireless communication method comprising: the arithmetic processing unit storing the read transmission power value in the main storage unit. The wireless communication method according to claim 8, 9 or 12,
The step (d)
(D-1 ′) the arithmetic processing unit controls the power supply unit to set the voltage of the transmission power to the value stored in the main storage unit;
(D-2 ′) the power supply unit supplies transmission power of the set value to the wireless transmission / reception unit;
(D-3 ′) A wireless communication method in which the wireless control unit performs wireless transmission using power supplied from the power supply unit.

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