JP3562691B2 - Wireless data collection device - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a wireless data collection apparatus that performs wireless data collection of devices, and more particularly to a wireless data collection apparatus that can reduce power consumption.
[0002]
[Prior art]
In the conventional data collection of equipment, a patrol member goes to the vicinity of the equipment, visually confirms an instruction value of the equipment, and manually inputs data to a device such as a handy terminal.
[0003]
Thus, in Japanese Patent Application No. 7-112216, etc., which is filed by the applicant of the present application, a device is provided with a transponder, and the data of the device is read out from the interrogator wirelessly, thereby enabling manual input to a device such as a handy terminal. Was unnecessary.
[0004]
In Japanese Patent Application No. Hei 7-112216, one antenna on the interrogator side is used for both transmission and reception by using a circulator, and two antennas are provided on the interrogator side for transmission and reception.
[0005]
However, when trying to reduce the size of the interrogator so that it is convenient to carry, using a circulator as described above can reduce the size but increase the cost.
[0006]
On the other hand, when the two antennas are configured using a printed circuit board having a commonly used dielectric constant, the antennas themselves become large and it is difficult to reduce the size. In addition, when a printed circuit board having a high dielectric constant is used for miniaturization, the gain of the antenna is reduced and the transmission distance of the interrogation wave sent from the interrogator is reduced.
[0007]
Therefore, as shown in Japanese Patent Application No. 8-007950 filed by the applicant of the present invention, when transmitting data in which transmission distance is a problem, the receiving antenna is switched to transmitting by the antenna function selecting means, and the two antennas are arrayed. By operating as an antenna, miniaturization was enabled while maintaining the transmission distance of the interrogation wave.
[0008]
FIG. 2 is a configuration block diagram showing an example of such a conventional example. In FIG. 2, 1 is an oscillator for generating a carrier, 2 and 4 are distributors, 3 and 18 are modulation circuits, 5, 8 and 15 are antennas, 6 and 7 are switch circuits, 9 is a terminating resistor, and 10 is a transmission data output. A circuit, 11 is a switch control circuit, 12 is an amplifier, 13 is a synchronous detection circuit, 14 is a display circuit, 16 is a detection circuit, 17 is a control circuit, and 19 is a sensor circuit.
[0009]
Also, 1 to 14 are interrogators 50, 15 to 18 are transponders 51, 1 to 3 and 10 are modulation means 52, 4, 6, 7, 9 and 11 are antenna function selection means 53, 12 and 13 constitutes a demodulation means 54, 16 and 17 constitute a detection means 55, and 18 constitutes a modulation means 56, respectively.
[0010]
The output of the oscillator 1 is connected to the distributor 2, and one output of the distributor 2 is connected to one input terminal of the modulation circuit 3. The output of the modulation circuit 3 is connected to a distributor 4, and one output of the distributor 4 is connected to an antenna 5. The output of the transmission data output circuit 10 is connected to the other input terminal of the modulation circuit 3.
[0011]
The other output of the distributor 4 is connected to the input terminal of the switch circuit 6, one output terminal of the switch circuit 6 is connected to the input terminal of the switch circuit 7, and the input / output terminal of the switch circuit 7 is connected to the antenna 8. You. The other output terminal of the switch circuit 6 is connected to one end of the terminating resistor 9, and the other end of the terminating resistor 9 is grounded.
[0012]
The output terminal of the switch circuit 7 is connected to the synchronous detection circuit 13, and the output of the synchronous detection circuit 13 is connected to the display circuit 14. The other output of the distributor 2 is connected to a carrier input terminal of a synchronous detection circuit 13 via an amplifier 12.
[0013]
Further, the control signal of the transmission data output circuit 10 is connected to the switch control circuit 11, and each control signal of the switch control circuit 11 is connected to the control terminals of the switch circuits 6 and 7, respectively.
[0014]
On the other hand, the output of the antenna 15 is connected to the detection circuit 16, and the output of the detection circuit 16 is connected to the control circuit 17. The output of the control circuit 17 is connected as a control signal to a sensor circuit 19 connected to the outside.
[0015]
The output of the sensor circuit 19 is connected to the modulation circuit 18, and the output of the modulation circuit 18 is connected to the antenna 15.
[0016]
Here, the operation of the conventional example shown in FIG. 2 will be described. In the interrogator 50, at the time of data transmission, the switch control circuit 11 determines that data transmission is to be performed based on a control signal from the transmission data output circuit 10, and switches the switch circuit 6 to the "A" side in FIG. Each is switched to the "C" side in FIG.
[0017]
On the other hand, the modulation circuit 3 performs ASK (Amplitude Shift Keying) modulation on the output signal of the oscillator 1 as a carrier based on the output data of the transmission data output circuit 10, and transmits the result as a query wave from the antenna 5 via the distributor 4.
[0018]
Since the output of the distributor 4 is also output to the antenna 8 via the switch circuits 6 and 7, the ASK-modulated interrogation wave is transmitted from the antenna 8 at the same time.
[0019]
When a series of data transmission is completed, the interrogator 50 enters a data reception state. In the data receiving state, the switch control circuit 11 determines that the data transmission has been completed based on the control signal from the transmission data output circuit 10, and sets the switch circuit 6 to the "b" side in FIG. Switch to the middle "d" side.
[0020]
In the data receiving state, the modulation circuit 3 transmits the output signal of the oscillator 1 as a carrier from the antenna 5 via the distributor 4 as it is as an unmodulated interrogation wave. At this time, the interrogation wave is not transmitted because the antenna 8 is used for reception.
[0021]
The transponder 51 receives the ASK-modulated interrogation wave transmitted from the interrogator 50 by the antenna 15, detects it by the detection circuit 16, and outputs it to the control circuit 17. The control circuit 17 interprets the contents of the data transmitted from the interrogator 50 and performs processing according to the contents of the data.
[0022]
For example, when the data content is a data read command from the externally connected sensor circuit 19, the control circuit 17 outputs a control signal to the sensor circuit 19.
[0023]
Then, the sensor circuit 19 outputs measurement data and the like to the modulation circuit 18 based on the control signal of the control circuit 17.
[0024]
The modulation circuit 18 applies BPSK (binary phase shift keying) modulation to the unmodulated interrogation wave transmitted from the interrogator 50 based on the output data of the sensor circuit 19, and reflects it as a response wave to the interrogator 50.
[0025]
The interrogator 50 receives the BPSK-modulated response wave reflected from the transponder 51 by the antenna 8 and inputs the response wave to the synchronous detection circuit 13 via the switch circuit 7.
[0026]
The synchronous detection circuit 13 synchronously detects the BPSK-modulated response wave based on the carrier supplied through the amplifier 12 and outputs the result to the display circuit 14. Then, the display circuit 14 displays the input data and the like.
[0027]
As a result, at the time of data transmission where the transmission distance is a problem, the antenna 8 is switched for transmission by the antenna function selecting means 53 and the antennas 5 and 8 are operated as an array antenna, so that the gain of the antenna is increased and The transmission distance of the ASK-modulated interrogation wave becomes longer.
[0028]
[Problems to be solved by the invention]
However, in the conventional example shown in FIG. Even at the time of data transmission of the interrogator 50, the output of the oscillator 1 is input to the synchronous detection circuit 13 constituting the demodulation means 54 via the amplifier 12, that is, although the demodulation processing is unnecessary, the amplifier 12 and the The synchronous detection circuits 13 were both in operation and the power consumption was wasted.
[0029]
In the data reception state of the interrogator 50, the modulation circuit 3 transmits the output signal of the oscillator 1 as a carrier as it is from the antenna 5 via the distributor 4 as an unmodulated interrogation wave. Is terminated by the terminating resistor 9 via the switch circuit 6, so that half of the output power from the modulation circuit 3 is wasted.
Accordingly, an object of the present invention is to realize a wireless data collection device capable of reducing power consumption.
[0030]
[Means for Solving the Problems]
In order to achieve such an object, in the first aspect of the present invention,
Interrogator, in a wireless data collection device comprising a transponder that modulates the interrogation wave from the interrogator based on data and reflects it as a response wave,
Said transponder;
Modulation means for outputting a modulated signal or a non-modulated carrier obtained by modulating a carrier based on transmission data; first and second antennas; and demodulation means for demodulating the response wave received by the second antenna based on the carrier. And transmitting the modulated signal as the interrogation wave from the first and second antennas, or transmitting an unmodulated carrier from the first antenna as the interrogation wave and transmitting the response wave to the second antenna. And an antenna function selecting means for selecting whether to supply the unmodulated carrier as the carrier to the demodulating means based on a state of the modulating means. Things.
[0031]
In order to achieve such an object, in the second aspect of the present invention,
In the first of the present invention,
A distributor that distributes the modulated signal or the unmodulated carrier and supplies one output to the first antenna; and supplies the modulated signal to the second antenna or supplies the response wave to the demodulation unit. A first switch circuit, a second switch circuit for supplying the modulation signal of the other output of the distributor to the first switch circuit or supplying the unmodulated carrier to the demodulation means, And a switch control circuit for controlling the first and second switch circuits based on the state of the means.
[0032]
In order to achieve such an object, in the third aspect of the present invention,
In the first and second aspects of the present invention,
The modulation means for outputting the ASK-modulated signal is used.
[0033]
In order to achieve such an object, in a fourth aspect of the present invention,
In the first and second aspects of the present invention,
The transponder performs BPSK modulation on the unmodulated carrier and reflects the response carrier as a response wave to the interrogator.
[0034]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a configuration block diagram showing one embodiment of a wireless data collection device according to the present invention.
[0035]
1, 1, 3 to 8, 10, 11, 13 to 19, 51, 55, and 56 are denoted by the same reference numerals as in FIG.
[0036]
1, 3 to 8, 10, 11, 13 and 14 are interrogators 50a, 1, 3 and 10 are modulating means 52a, 4, 6, 7 and 11 are antenna function selecting means 53a, and 10 is demodulation. Each of the means 54a is constituted.
[0037]
An output of the oscillator 1 is connected to one input terminal of the modulation circuit 3, an output of the modulation circuit 3 is connected to a distributor 4, and one output of the distributor 4 is connected to an antenna 5. The output of the transmission data output circuit 10 is connected to the other input terminal of the modulation circuit 3.
[0038]
The other output of the distributor 4 is connected to the input terminal of the switch circuit 6, one output terminal of the switch circuit 6 is connected to the input terminal of the switch circuit 7, and the input / output terminal of the switch circuit 7 is connected to the antenna 8. You.
[0039]
The output terminal of the switch circuit 7 is connected to the synchronous detection circuit 13, and the output of the synchronous detection circuit 13 is connected to the display circuit 14. The other output terminal of the switch circuit 6 is connected to the carrier input terminal of the synchronous detection circuit 13.
[0040]
Further, the control signal of the transmission data output circuit 10 is connected to the switch control circuit 11, and each control signal of the switch control circuit 11 is connected to the control terminals of the switch circuits 6 and 7, respectively.
[0041]
However, the connection relation regarding the transponder 51 is the same as that of the conventional example shown in FIG.
[0042]
Here, the operation of the embodiment shown in FIG. 1 will be described. The basic operation is the same as that of the conventional example. At the time of data transmission in the interrogator 50a, the switch control circuit 11 determines that data transmission is to be performed based on a control signal from the transmission data output circuit 10, and switches the switch circuit 6 in FIG. The switch circuit 7 is switched to the "A" side in FIG. 1 and to the "C" side in FIG.
[0043]
On the other hand, the modulation circuit 3 performs ASK (Amplitude Shift Keying) modulation on the output signal of the oscillator 1 as a carrier based on the output data of the transmission data output circuit 10, and transmits the result as a query wave from the antenna 5 via the distributor 4.
[0044]
Since the output of the distributor 4 is also output to the antenna 8 via the switch circuits 6 and 7, the ASK-modulated interrogation wave is transmitted from the antenna 8 at the same time.
[0045]
At this time, the synchronous detection circuit 13 is in a non-operating state because no carrier is input to the carrier input terminal.
[0046]
When a series of data transmission is completed, the interrogator 50a enters a data reception state. In the data receiving state, the switch control circuit 11 determines that the data transmission has been completed based on the control signal from the transmission data output circuit 10, and sets the switch circuit 6 to the "b" side in FIG. Switch to the middle "d" side.
[0047]
In the data receiving state, the modulation circuit 3 transmits the output signal of the oscillator 1 as a carrier from the antenna 5 via the distributor 4 as it is as an unmodulated interrogation wave. At this time, the interrogation wave is not transmitted because the antenna 8 is used for reception.
[0048]
In the transponder 51, the non-modulated interrogation wave from the interrogator 50a is subjected to BPSK (binary phase shift keying) modulation and reflected as a response wave to the interrogator 50a as in the conventional example.
[0049]
The interrogator 50a receives the BPSK-modulated response wave reflected from the transponder 51 by the antenna 8, and inputs the response wave to the synchronous detection circuit 13 via the switch circuit 7.
[0050]
At this time, the modulation circuit 3 outputs the output signal of the oscillator 1 as a carrier as it is, and this output is also supplied to the carrier input terminal of the synchronous detection circuit 13 via the distributor 4 and the switch circuit 6. Become.
[0051]
Therefore, the synchronous detection circuit 13 synchronously detects the response wave based on the carrier supplied through the distributor 4 and the switch circuit 6 and outputs the response wave to the display circuit 14. Then, the display circuit 14 displays the input data and the like.
[0052]
That is, at the time of data transmission by the interrogator 50a, no carrier is supplied to the synchronous detection circuit 13 constituting the demodulation means 54a, so that the synchronous detector 13 is in a non-operating state and the power consumption is reduced. Since the carrier is supplied to the synchronous detection circuit 13 via the switch circuit 6, half of the output power from the modulation circuit 3 is not wasted.
[0053]
Further, when the interrogator 50a is driven by a battery, it is possible to extend the life of the battery, so that the size of the battery can be reduced.
[0054]
As a result, the unmodulated interrogation wave output from the modulation circuit 3 is supplied to the synchronous detection circuit 13 as a carrier by the antenna function selection means 53a at the time of data reception, and the carrier is not supplied at the time of data transmission, thereby reducing power consumption. Becomes possible.
[0055]
In the embodiment shown in FIG. 1, a wireless data collection system is exemplified, but it is of course possible to apply the present invention to a mobile object identification device.
[0056]
In addition, BPSK is exemplified as a modulation method of the response wave reflected by the transponder 51, but ASK (Amplitude Shift Keying), QPSK (Quadrature Phase Shift Keying), and QAM (Quadrature Amplitude Modulation), and the like are good modulation methods. .
[0057]
【The invention's effect】
As is apparent from the above description, the present invention has the following effects.
An antenna function selecting means supplies an unmodulated interrogation wave output from the modulation circuit as a carrier to the synchronous detection circuit at the time of data reception to the synchronous detection circuit, and does not supply the carrier at the time of data transmission, thereby reducing power consumption. The device can be realized.
[Brief description of the drawings]
FIG. 1 is a configuration block diagram illustrating an embodiment of a wireless data collection device according to the present invention. FIG. 2 is a configuration block diagram illustrating an example of a conventional example.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Oscillator 2, 4 Divider 3, 18 Modulation circuit 5, 8, 15 Antenna 6, 7 Switch circuit 9 Termination resistor 10 Transmission data output circuit 11 Switch control circuit 12 Amplifier 13 Synchronous detection circuit 14 Display circuit 16 Detection circuit 17 Control circuit 19 Sensor circuits 50, 50a Interrogator 51 Transponders 52, 52a, 56 Modulation means 53, 53a Antenna function selection means 54, 54a Demodulation means 55 Detection means

Claims (4)

Interrogator, in a wireless data collection device comprising a transponder that modulates the interrogation wave from the interrogator based on data and reflects it as a response wave,
Said transponder;
Modulation means for outputting a modulated signal or a non-modulated carrier obtained by modulating a carrier based on transmission data; first and second antennas; and demodulation means for demodulating the response wave received by the second antenna based on the carrier. And transmitting the modulated signal as the interrogation wave from the first and second antennas, or transmitting an unmodulated carrier from the first antenna as the interrogation wave and transmitting the response wave to the second antenna. And an antenna function selecting means for selecting whether to supply the unmodulated carrier as the carrier to the demodulating means based on a state of the modulating means. Wireless data collection device. A distributor that distributes the modulated signal or the unmodulated carrier and supplies one output to the first antenna; and supplies the modulated signal to the second antenna or supplies the response wave to the demodulation unit. A first switch circuit, a second switch circuit for supplying the modulated signal of the other output of the distributor to the first switch circuit or supplying the unmodulated carrier to the demodulation means, 2. The wireless data collection device according to claim 1, wherein said antenna function selecting means comprises a switch control circuit for controlling said first and second switch circuits based on a state of said means. apparatus. 3. The wireless data collection device according to claim 1, wherein the modulation unit that outputs the ASK-modulated signal is used. 3. The wireless data collection device according to claim 1, wherein the transponder applies BPSK modulation to the unmodulated carrier and reflects the non-modulated carrier as a response wave to the interrogator.

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