JP5217758B2 - Non-contact communication device and antenna device - Google Patents

Description

  The present invention relates to a non-contact communication device that communicates with a non-contact IC medium in a non-contact manner, for example, and an antenna device used in the non-contact communication device.

  Conventionally, a non-contact IC medium called an RF-ID tag or an RF-ID card, and a non-contact communication apparatus that performs non-contact communication with the non-contact IC medium are provided. This non-contact communication apparatus is provided with a scan antenna that performs non-contact communication with a non-contact IC medium, and a reader / writer that performs communication control by transmitting and receiving signals to and from the scan antenna. The scan antenna and the reader / writer are connected by a transmission cable such as a coaxial cable, and an RF signal is transmitted and received between them.

  On the other hand, as such a non-contact communication apparatus, a reader capable of changing the directivity for non-contact communication has been proposed by the applicant (see Patent Document 1). This Patent Document 1 describes that field holes can be reduced by changing the directivity of an antenna portion provided in a scan antenna under the control of a reader / writer (see paragraph [0080]).

  Here, the antenna unit is connected to the reader / writer via a transmission cable, and transmits / receives a modulated signal obtained by modulating transmission data to / from the reader / writer via this transmission cable. And in order to control the directivity of an antenna part, in addition to this transmission cable, the control cable which transmits the antenna designation | designated signal 28 shown by FIG. 1 of patent document 1, and FIG. 7 of patent document 1 are shown. A control cable for transmitting the scan control signal 54 is required.

However, when there are two cables in this way, there is a problem that the connection work is complicated when the scan antenna and the reader / writer are installed and connected in different places.
JP 2007-292744 A

  In view of the above-described problems, an object of the present invention is to provide a non-contact communication device and an antenna device that can control the antenna unit as well as the communication with one transmission cable without connecting a separate control cable. To do.

  The present invention includes an antenna unit that can change a directivity direction and performs a non-contact communication by the antenna unit, and a communication signal connected to the directivity variable antenna via a transmission cable. A non-contact communication device including a reader / writer that performs communication control by transmitting and receiving a signal to the reader / writer through a transmission cable together with the communication signal and a directivity direction switching signal for switching the directivity direction of the antenna unit. A non-contact communication apparatus comprising a switching signal transmission means for transmitting, and an antenna operation switching means for detecting the directivity direction switching signal and switching the directivity direction of the antenna unit on the directivity variable antenna. And

  The directivity direction switching signal is a signal that can be recognized by the antenna operation switching means at least when the directivity direction can be switched, such as a trigger signal indicating only switching or an instruction signal instructing which directivity direction to use. be able to.

  Further, the directivity direction switching signal includes the communication signal output ON, output OFF, the combination of output ON and output OFF, the time when the communication signal is output OFF, the voltage difference of the DC voltage superimposed on the communication signal. Other systems without damaging the communication signal, such as the rise or fall of the DC voltage superimposed on the communication signal, the amplitude modulated signal of the DC voltage superimposed on the communication signal, and the signal of a different frequency superimposed on the communication signal The signal can be obtained by an appropriate method of adding the above signal.

  The switching signal transmitting means is a communication signal transmitting means for controlling the time for which the communication signal is output ON, output OFF, or the communication signal is output OFF, and the switching control of the voltage difference of the DC voltage superimposed on the communication signal. , Rise or fall control of the DC voltage superimposed on the communication signal, voltage control means for controlling the amplitude modulation of the DC voltage superimposed on the communication signal, and instructions for transmitting signals of different frequencies superimposed on the communication signal The signal can be obtained by an appropriate method of adding a signal of another system without damaging the communication signal, such as a signal transmission unit.

  The antenna operation switching means stores a plurality of types of phase patterns that determine the directivity direction of the antenna unit in an appropriate storage means such as a nonvolatile memory, and each phase pattern in a predetermined order or randomly every time a trigger signal is received. Or a means for switching the directivity direction, such as a means for receiving an instruction signal designating the directivity direction and switching to a phase pattern corresponding to the instruction signal.

  According to the present invention, it is possible to provide a non-contact communication device capable of controlling the directivity direction of the antenna unit together with communication with one transmission cable without connecting a separate control cable. In addition, it is possible to ensure that the directivity direction switching timing of the directivity variable antenna is after receiving an instruction from the reader / writer. For this reason, it can be prevented that the directivity variable antenna independently changes the directivity direction and the communication is disconnected while the reader / writer is performing communication processing.

As an aspect of the present invention, the reader / writer can be provided with output means for outputting the directivity direction of the antenna unit so that a human can recognize it.
The output means may be an appropriate notification such as an image display means such as a liquid crystal display or an organic EL display for displaying an image, a light emitting display means having a plurality of light emitting means such as LEDs to indicate a directivity direction, an audio output means for notifying by voice. It can be a means.
By this aspect, the user can easily recognize the current pointing direction.

  Further, as an aspect of the present invention, the switching signal transmission means is configured to instruct switching of a directivity direction by at least one of output ON and output OFF of the communication signal, and the antenna operation switching means is configured to output the output ON and output. It can be configured to detect at least one of OFF and switch the directivity direction of the antenna unit.

  Thereby, it is possible to realize switching of the directivity direction of the antenna unit through the transmission cable without hindering the communication processing of the reader / writer through the transmission cable with a simple configuration using the output ON and the output OFF of the communication signal.

  Further, as an aspect of the present invention, the antenna operation switching of the directivity variable antenna is provided between the switching signal transmission unit of the reader / writer and the transmission cable, and includes a power supply unit that superimposes a DC voltage on the communication signal. Means for detecting the output of the communication signal; a phase control unit for controlling the phase of the signal transmitted to the antenna unit; and output and ON of the communication signal detected by the power detection unit A control circuit unit that controls the phase control unit using at least one of OFF as the directivity direction switching signal can be configured.

As a result, the reader / writer can add a directivity direction switching signal that triggers the superposition of the DC voltage and the switching of the directivity direction to the communication signal with a simple configuration. Further, variable directivity antenna can detects the pointing direction switching signal with a simple configuration to switch the directivity direction of the antenna unit.

  Further, as an aspect of the present invention, the antenna operation switching means includes: a power detection unit that detects an output of the communication signal; a phase control unit that controls a phase of a signal transmitted to the antenna unit; and the power detection unit. A control circuit unit that controls the phase control unit based on at least one of output ON and output OFF of the detected communication signal, and rectifies a part of the communication signal coming from the transmission cable to extract a DC voltage And a DC voltage extraction unit for supplying each unit.

  Thus, if a directivity variable antenna is prepared, it can be used simply by installing software on an existing reader / writer.

  The present invention also includes an antenna unit that can change a directivity direction, a power detection unit that detects an output of a communication signal received from a transmission cable, a phase control unit that controls a phase of a signal transmitted to the antenna unit, A control circuit unit that controls the phase control unit based on at least one of output ON and output OFF of the communication signal detected by the power detection unit, and rectifies a part of the communication signal received from the transmission cable The antenna device may include a DC voltage extraction unit that extracts a DC voltage and supplies the DC voltage to each unit.

  Accordingly, it is possible to provide an antenna device that can change the directing direction in response to an instruction from the reader / writer.

  According to the present invention, it is possible to provide a non-contact communication apparatus and an antenna apparatus that can control the antenna unit as well as the communication with one transmission cable without connecting a separate control cable.

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

  FIG. 1 is a block diagram showing a configuration of a non-contact communication system 1 that performs non-contact communication with a non-contact IC medium called an RF-ID tag or an RF-ID card. FIG. 2 is a perspective view showing an external configuration of the scan antenna 30.

  The non-contact communication system 1 mainly includes a PC 2, a reader / writer 10, and a scan antenna 30. The reader / writer 10 and the scan antenna 30 are connected by a coaxial cable 20, and the reader / writer 10 and the scan antenna 30 connected by the coaxial cable 20 constitute a non-contact communication device 5.

  The PC 2 is a personal computer, and is composed of input means such as a mouse and keyboard, display means such as a CRT display, communication means such as a LAN card, control means composed of a CPU, ROM and RAM, a hard disk, and the like. It is composed of appropriate components such as storage means.

  The reader / writer 10 is provided with an RF transmission / reception unit 11 and a capacitor 12 connected to the subsequent stage of the RF transmission / reception unit 11, and a coaxial cable 20 is connected to the subsequent stage of the capacitor 12. Further, the reader / writer 10 is provided with a DC power supply 15 and a coil 16 connected to the subsequent stage of the DC power supply 15, and a coaxial cable 20 is connected to the subsequent stage of the coil 16. Therefore, it branches off from one coaxial cable 20, the capacitor 12 and the RF transmitter / receiver 11 are connected in series in this order on one side, and the coil 16 and the DC power supply 15 are connected in series in this order on the other side. .

  The RF transmission / reception unit 11 is formed in an appropriate circuit configuration including a control unit, a modulation unit, an amplification unit, and the like, and executes transmission / reception of an RF signal to / from the scan antenna 30 via the capacitor 12.

  The DC power supply 15 smoothes the AC power supplied from the AC power supply 4 to generate a DC voltage, and superimposes this DC voltage on the RF signal via the coil 16. This superimposed signal is transmitted to the scan antenna 30 via the coaxial cable 20.

  The reader / writer 10 is connected to the PC 2 via the LAN cable 3. Therefore, when a control signal is received from the PC 2 via the LAN cable 3, the RF transmission / reception unit 11 can execute an operation according to the control signal.

  The scan antenna 30 includes an antenna unit 31, a phase control unit 32, a capacitor 33, a coil 35, an RF power detector 39, a display 41, and a control circuit unit 40.

  A phase control unit 32 is connected to the antenna unit 31 at the subsequent stage, a capacitor 33 is connected to the subsequent stage, and the coaxial cable 20 is connected to the subsequent stage of the capacitor 33. A control circuit unit 40 is also connected to the phase control unit 32. The control circuit unit 40 is connected to a coil 35 that is branched between the capacitor 33 and the coaxial cable 20 and provided in parallel with the capacitor 33. Similarly, an RF power detector 39 that branches between the branch section and the coaxial cable 20 and is provided in parallel with the capacitor 33 is connected to the control circuit section 40. A display 41 is also connected to the control circuit unit 40.

  The antenna unit 31 can change the directivity direction. Specifically, for example, the antenna unit 31 can be configured by a three-element array antenna whose directing direction can be adjusted from 35 ° to −35 °. Further, the change of the directivity direction is executed by controlling the phase difference that supplies power to each of a plurality of antenna elements. As the directivity direction, for example, pattern 1 (35 °, communication area 51), pattern 2 (0 °, communication area 52), and pattern 3 (-35 °, communication area 53) are set in appropriate directions. Can be set.

  The phase control unit 32 stores a plurality of phase patterns, and controls the phase difference to be fed to each of the plurality of antenna elements provided in the antenna unit 31 according to the phase patterns. Thus, phase control is performed, and the directivity direction of the antenna unit 31 is changed.

  The RF power detector 39 detects whether or not power is supplied from the coaxial cable 20, that is, whether or not radio waves are emitted from the antenna unit 31, and transmits a detection signal to the control circuit unit 40.

  As shown in FIG. 2, the display device 41 is composed of a plurality of LEDs 41a to 41c. The indicator 41 lights any one of the LEDs 41a to 41c to display the current pointing direction of the antenna unit 31 so that a human can recognize it.

  As shown in FIG. 1, the control circuit unit 40 changes the directivity direction of the antenna unit 31 by transmitting a control signal to the phase control unit 32 according to the switching signal received from the coaxial cable 20 via the RF power detector 39. Let In addition, the control circuit unit 40 stores the directivity direction switching law in a storage unit such as a memory in order to change the directivity direction. In the first embodiment, the control circuit unit 40 detects whether the RF signal is ON, OFF, fixed time OFF, or a plurality of these as a switching signal, and when this switching signal is detected, the designated direction switching law (predetermined order) is detected. Or the direction of the antenna unit 31 is switched to the phase control unit 32 in accordance with the random number).

  A configuration in which the directivity direction switching setting that determines the directivity direction of the antenna unit 31 for each OFF time when the RF signal is OFF may be stored in the storage unit of the control circuit unit 40. In this case, the control circuit unit 40 determines the directivity direction corresponding to the time when the RF signal is turned off based on the designated direction switching setting, and sets the directivity direction of the antenna unit 31 to be the determined directivity direction. It is good to make the control part 32 switch. When configured in this way, the reader / writer 10 can control in which directivity direction the scan antenna 30 is contactlessly communicated.

FIG. 3 is a flowchart for explaining the operation of the contactless communication system 1.
The RF transmitter / receiver 11 of the reader / writer 10 initializes the variable n by substituting 1 for the variable n (step S1), and instructs the scan antenna 30 to set the directivity of the antenna unit 31 (step S1). S2). This instruction may be given by an appropriate signal such as RF signal output ON, OFF, or OFF for a certain period of time. In this embodiment, the following description will be given with respect to the case where OFF is performed for a certain period of time.

  The control circuit unit 40 of the scan antenna 30 detects the directivity set instruction by the RF power detector 39, transmits a signal to the phase control unit 32, and sets the directivity direction by the antenna unit 31 (step S11). At this time, the control circuit unit 40 also sets the display of the directivity direction by the display device 41 to the display indicating the set directivity direction.

  The RF transmission / reception unit 11 of the reader / writer 10 starts transmission of an RF signal (step S3), and performs communication between the non-contact communication device 5 and the non-contact IC medium (step S4).

  The RF transmission / reception unit 11 continues the communication until communication with all non-contact IC media in the communication area of the antenna unit 31 in the current pointing direction is completed (step S5: No). Communication with all these non-contact IC media is performed by anti-collision.

  When communication with all the non-contact IC media in the communication area is completed (step S5: Yes), the RF transceiver 11 stops the RF signal (step S6) and changes the directivity of the antenna unit 31. An instruction is given to the scan antenna 30 (step S7). This instruction may be performed by an appropriate predetermined signal such as ON / OFF of the RF signal or OFF for a certain period of time.

  The control circuit unit 40 of the scan antenna 30 detects the directivity change instruction by the RF power detector 39, transmits a signal to the phase control unit 32, and changes the directivity direction by the antenna unit 31 (step S12). At this time, for changing the directivity direction, the changed directivity direction is determined according to a predetermined appropriate standard, such as setting to the next directivity direction according to a predetermined order, or setting the directivity direction at random. It should be noted that settings such as the changing direction of the directivity direction may be stored in a memory (not shown) provided in the control circuit unit 40. At this time, the control circuit unit 40 also changes the display of the directivity direction on the display device 41 to the display indicating the changed directivity direction.

  The RF transmitter / receiver 11 returns the process to step S3 after changing the directivity direction and repeats the communication operation from steps S3 to S6. By performing this communication operation in all directivity directions, communication is performed with all non-contact IC media existing somewhere for the entire communication area including all communicable areas in each directivity direction of the antenna unit 31. can do.

  With the above configuration and operation, communication with the non-contact IC medium and switching of the directivity direction of the scan antenna 30 can be realized only by the coaxial cable 20 without providing a separate control cable for the connection between the reader / writer 10 and the scan antenna 30. can do. Accordingly, it is possible to eliminate the trouble of connecting the reader / writer 10 and the scan antenna 30 with the two cables of the coaxial cable and the control cable as in the conventional case.

  Switching of the directivity direction of the scan antenna 30 is not performed by the scan antenna 30 on its own, but is performed by an instruction from the reader / writer 10, so that reliable communication between the non-contact IC medium and the non-contact communication device 5 can be realized. it can. That is, if the scanning antenna 30 switches the directivity direction at an appropriate timing independently of the operation of the reader / writer 10, the directivity direction may change during communication by the reader / writer 10 and a communication error may occur. When a communication error occurs in this way, the directivity direction has been changed to another communication area even though communication with all the non-contact IC media in the communication area has not been completed. On the other hand, by switching the directivity direction at the timing according to the instruction from the reader / writer 10, it is possible to prevent the directivity direction from being switched during the communication as described above, and to realize reliable communication. In particular, when there are a plurality of non-contact IC media in the communication area, the time for completing communication with all the non-contact IC media by anti-collision varies depending on the number of non-contact IC media. Also in such a case, after the reader / writer 10 has completed communication with all the non-contact IC media, it is possible to instruct switching of the directivity direction, and the scan antenna 30 can change the directivity direction in response to this instruction. Therefore, as soon as the reading time is completed in a short time, the next directivity direction can be changed and communication can be performed in the next communication area. If the reading time is long, all communication is completed. The waiting direction can be changed after waiting, and communication in each pointing direction can be performed efficiently and reliably.

  Further, since the directivity direction switching rule or the directivity direction switching setting is stored in the control circuit unit 40 of the scan antenna 30, a signal for changing the directivity direction received via the coaxial cable 20 is a simple ON / OFF signal. It can be. Thereby, the change of the directivity direction of the scan antenna 30 based on the instruction from the reader / writer 10 can be realized with a simple circuit configuration.

  In addition, since the display device 41 is provided, it is possible for a human to visually confirm which direction the scan antenna 30 is directed. Therefore, what is invisible to the human eye, that is, the direction of communication by the antenna unit 31, can be visualized by the display device 41. Thereby, the installation adjustment of the scan antenna 30 can be facilitated.

FIG. 4 is a block diagram illustrating a configuration of the non-contact communication system 1a according to the second embodiment.
The reader / writer 10a of the non-contact communication device 5a is provided with a voltage control unit 17 instead of the DC power supply 15 of the first embodiment. The voltage control unit 17 switches the DC voltage superimposed on the communication signal to a plurality of types of voltages.

  The scan antenna 30a is the same as the first embodiment except that the RF power detector 39 of the first embodiment is omitted. Note that the display (the display 41 of the first embodiment) is not shown.

Since other configurations are the same as those of the first embodiment, detailed description thereof is omitted.
The non-contact communication system 1a configured as described above operates in the same manner as the flowchart described with reference to FIG. 3 of the first embodiment, but the directivity set in steps S2 and S7 and the directivity change in steps S11 and S12. Only the instruction method is different. That is, in step S2, the voltage control unit 17 issues a directivity setting instruction based on the difference in voltage superimposed on the RF signal.
In step S11, the scan antenna 30a that has received the set instruction sets the directivity corresponding to the received voltage and starts communication. More specifically, the control circuit unit 40 detects the voltage, and the control circuit unit 40 determines the directivity according to the detected voltage, and changes the directivity of the antenna unit 31 to the determined directivity.

In step S <b> 7, the voltage control unit 17 issues a directivity setting instruction based on the voltage difference superimposed on the RF signal.
In step S12, the control circuit unit 40 of the scan antenna 30 that has received this determines the directivity according to the detected voltage, and changes the directivity of the antenna unit 31 to the determined directivity.

  With the above configuration and operation, the same effects as those of the first embodiment can be achieved. In addition, since the superimposed voltage can be made different, when the antenna unit 31 receives the superimposed voltage, the antenna unit 31 is changed so as to change the communication areas 51 to 53 in the directivity direction corresponding to the voltage value. Can be controlled.

In this embodiment, the directivity direction is changed depending on the voltage difference, but the directivity direction may be changed by another method using a DC voltage.
For example, as shown in the timing chart of FIG. 5A, the directing direction may be changed by the rising and falling of the DC voltage superimposed on the RF signal. In this case, when the DC voltage rises, for example, the directivity direction of the pattern 1 is set as illustrated, and when the DC voltage falls, the RF output is stopped. Further, when the DC voltage rises next time, it is preferable to transmit the RF signal with a pattern 2 different from the previous one. The order of the patterns 1 to 3 may be in the order of numbers or may be selected at random. Even in this case, the same effects as described above can be obtained. In addition, by using the rise or fall of the DC voltage in this way, it is not necessary to change the voltage, and the circuit configuration can be simplified.

  Further, as shown in the timing chart of FIG. 5B, the directivity voltage may be changed by amplitude-modulating the DC voltage superimposed on the RF signal. In this case, the control circuit unit 40 receives the amplitude-modulated DC voltage, for example, sets the directivity direction of the pattern 1 as shown, and then receives the amplitude-modulated DC voltage and sets the directivity direction of the pattern 3. In this way, it is preferable to set the directivity direction according to the type of amplitude modulation. Even in this case, the same effects as described above can be obtained.

FIG. 6 is a block diagram illustrating a configuration of the contactless communication system 1b according to the third embodiment.
The reader / writer 10b of the non-contact communication device 5b is provided with an HPF (High Pass Filter) 13, an LPF (Low Pass Filter) 14, and a scan control RF transceiver 18 in addition to the configuration of the first embodiment.

The HPF 13 is connected to the RF transmitter / receiver 11 side rather than the branching portion where the coaxial cable 20 branches to the RF transmitter / receiver 11 and the DC power supply 15.
The LPF 14 is connected to the tip of a branch provided between the branch portion and the coaxial cable 20, and is connected in parallel to the coil 16.
The scan control RF transceiver 18 is connected to the preceding stage of the LPF 14.

  With this configuration, the reader / writer 10b can use a high frequency as a communication signal and use a low frequency as a control signal in a directivity direction. That is, the communication signal transmitted / received by the RF transmitter / receiver 11 is made high frequency by the HPF 13, and the DC voltage supplied from the DC power supply 15 via the coil 16 is superimposed. A signal for switching and controlling the directivity direction transmitted from the scan control RF transmitting / receiving unit 18 is made to have a low frequency by the LPF 14 and further superimposed on a signal in which a DC voltage is superimposed on a communication signal, and is then superimposed on the scan antenna 30 b by the coaxial cable 20. Sent to.

  Compared with the scan antenna 30 of the first embodiment, the scan antenna 30b is provided with an LPF (low-pass filter) 36 instead of the RF power detector 39, and other components are the same.

The scan antenna 30b obtains a control signal in the directivity direction from the low frequency component extracted by the LPF 36, and the control circuit unit 40 controls the phase control unit 32 in accordance with the control signal. Thereby, the directivity direction of the antenna unit 31 is controlled.
Since other configurations are the same as those of the first embodiment, detailed description thereof is omitted.

  The non-contact communication system 1b configured as described above operates in the same manner as the flowchart described with reference to FIG. 3 of the first embodiment, but the directivity set in steps S2 and S7 and the directivity change in steps S11 and S12. Only the method of instruction is different.

  That is, in steps S2 and S7, the scan control RF transceiver 18 superimposes a low-frequency control signal on the RF signal. In steps S11 and S12, the control circuit unit 40 of the scan antenna 30 obtains a control signal by separating and acquiring the low frequency component from the RF signal by the LPF 36, and controls the phase control unit 32 by the control signal to control the antenna. The directivity direction of the unit 31 is changed.

  With the above configuration and operation, the same effects as those of the first embodiment can be achieved. Since the control signal to be superimposed can be made different, when the antenna unit 31 receives the superimposed control signal, the communication areas 51 to 53 are changed toward the directivity direction corresponding to the control signal. Thus, the antenna unit 31 can be controlled.

  In this embodiment, the program stored in the control circuit unit 40 may be updated from the reader / writer 10. In this case, a new program may be transmitted from the scan control RF transmitting / receiving unit 18 at a low frequency, and the old program stored in the memory of the control circuit unit 40 may be rewritten with a new program. Thereby, when the program for operating the scan antenna 30 needs to be updated, it can be updated from the reader / writer 10.

FIG. 7 is a block diagram illustrating a configuration of the non-contact communication system 1c according to the fourth embodiment.
The reader / writer 10c of the non-contact communication device 5c is configured by deleting the capacitor 12, the DC power supply 15, and the coil 16 from the configuration of the first embodiment. That is, the reader / writer 10c does not have a special component for controlling the directivity direction, and is manufactured in the same configuration as an existing reader / writer.

  A program for controlling the directivity of the antenna unit 31 of the scan antenna 30 is stored in an appropriate storage unit of the RF transceiver unit 11. This program transmits a control signal for directivity control by output ON, output OFF, or a combination of output ON and output OFF of a communication signal transmitted from the RF transceiver 11. In the combination of output ON and output OFF, for example, a plurality of OFF times from when the output is turned off until when the output is turned on are prepared, and the pointing direction can be specified based on the OFF time.

  Compared with the scan antenna 30 of the first embodiment, the scan antenna 30c has no capacitor 33, and instead of the coil 35, an RF rectifier circuit unit 37 and a power storage unit 38 are provided in series, and other components are the same. It is configured.

  The scan antenna 30c detects the output ON / OFF of the communication signal by the RF power detector 39, and the control circuit unit 40 controls the phase control unit 32 by the output ON / OFF. Thereby, the directivity direction of the antenna unit 31 is controlled.

  The RF rectifier circuit unit 37 rectifies a part of the communication signal supplied from the coaxial cable 20 and extracts a DC voltage. The power storage unit 38 stores the extracted DC voltage and stabilizes the operation.

The power storage unit 38 has a function of continuously supplying power to each unit as a battery, and the communication signal supplied from the coaxial cable 20 is interrupted due to a change in the direction of the antenna unit 31 (output OFF). Even if the power is stored, the power is continuously supplied to each unit by the stored power. As a result, it is possible to prevent the control circuit unit 40 from being turned off every time the directivity direction is changed and to start the operation from the beginning, thereby enabling continuous operation.
Since other configurations are the same as those of the first embodiment, detailed description thereof is omitted.

  The non-contact communication system 1c configured as described above operates in the same manner as the flowchart described in FIG. 3 of the first embodiment, but the directivity set in steps S2 and S7 and the directivity change in steps S11 and S12. Only the method of instruction is different.

  That is, in steps S2 and S7, the scan control RF transceiver 18 executes ON / OFF of the output of the communication signal. In steps S11 and S12, the control circuit unit 40 of the scan antenna 30c detects the ON or OFF by the RF power detector 39, and controls the phase control unit 32 by this detection to change the directivity direction of the antenna unit 31. Let

  With the above configuration and operation, the same effects as those of the first embodiment can be achieved. Further, an existing reader / writer can be used as the reader / writer 10c, and it can be dealt with only by software update.

FIG. 8 is a block diagram illustrating a configuration of a contactless communication system 1d according to the fifth embodiment.
The reader / writer 10 d includes an HPF 13 instead of the capacitor 12, an LPF 14 instead of the coil 16, and a scan control RF transmitter / receiver 18 instead of the DC power supply 15 in the configuration of the first embodiment.

  With this configuration, the reader / writer 10d can use a high frequency as a communication signal and use a low frequency as a control signal in a directivity direction. That is, the communication signal transmitted / received by the RF transmission / reception unit 11 is made high frequency by the HPF 13, and the signal for switching control of the directivity direction transmitted from the scan control RF transmission / reception unit 18 is made low frequency by the LPF 14 for communication. The signal is superimposed on the signal for transmission and transmitted to the scan antenna 30d through the coaxial cable 20.

  Compared to the scan antenna 30 of the first embodiment, the scan antenna 30d includes an HPF 34 instead of the capacitor 33, an RF rectifier circuit unit 37 instead of the coil 35, and an LPF 36 instead of the RF power detector 39. Other components are configured identically.

The scan antenna 30d obtains a control signal in the directivity direction from the low-frequency component extracted by the LPF 36, and the control circuit unit 40 controls the phase control unit 32 according to the control signal. Thereby, the directivity direction of the antenna unit 31 is controlled.
Since other configurations are the same as those of the first embodiment, detailed description thereof is omitted.

  The non-contact communication system 1b configured as described above operates in the same manner as the flowchart described with reference to FIG. 3 of the first embodiment, but the directivity set in steps S2 and S7 and the directivity change in steps S11 and S12. Only the method of instruction is different.

  That is, in steps S2 and S7, the scan control RF transceiver 18 superimposes a low-frequency control signal on the RF signal. In steps S11 and S12, the control circuit unit 40 of the scan antenna 30 obtains a control signal by separating and acquiring the low frequency component from the RF signal by the LPF 36, and controls the phase control unit 32 by the control signal to control the antenna. The directivity direction of the unit 31 is changed.

  With the above configuration and operation, the same effects as those of the first embodiment can be achieved. In addition, since a plurality of types of signals can be used as superimposed control signals, when the antenna unit 31 receives the superimposed control signals, the communication areas 51 to 53 are directed toward the directivity direction corresponding to the control signals. The antenna unit 31 can be controlled to change.

In addition, the configuration of the display 41 of the scan antenna 30 and the setting of the directing direction to be changed in each of the above-described embodiments can be an appropriate configuration and setting.
For example, as shown in the perspective view of FIG. 9A, the directivity directions of the patterns 1 to 5 (communication areas 51 to 55) may be displayed by a combination of the print display 42 and the LEDs 41a to 41e. In this case, the print display 42 may be printed with angle display characters 43 and direction display lines 44 as shown in FIG.

  Accordingly, if any one of the LEDs 41a to 41e is turned on, the user can visually recognize the printed display 42 and easily check the current directivity direction. In the example shown in the figure, the directivity direction is set to five levels, but the user can easily recognize which direction of the five levels is the current communication area.

  Further, a liquid crystal display may be provided as the display device 41 as shown in FIG. In this case, an arrow 45 and an angle 46 may be displayed on the liquid crystal display as shown in FIG.

  Also in this case, the user can easily recognize the directivity direction. In addition, when the setting type of the directivity direction is set to different settings such as three steps and five steps depending on the user's request, it can be handled only by software setting without changing the hardware, and versatility can be increased.

In correspondence between the configuration of the present invention and the above-described embodiment,
The switching signal transmission means of the present invention corresponds to the RF transmission / reception unit 11, the voltage control unit 17, or the scan control RF transmission / reception unit 18 of the embodiment.
Similarly,
The power supply means corresponds to the DC power supply 15,
The transmission cable corresponds to the coaxial cable 20,
The directivity variable antenna and the antenna device correspond to the scan antenna 30,
The antenna operation switching means corresponds to the phase control unit 32 and the control circuit unit 40,
The DC voltage extraction unit corresponds to the RF rectification circuit unit 37,
The power detector corresponds to the RF power detector 39,
The output means corresponds to the display device 41,
The communication signal corresponds to the RF signal,
The present invention is not limited only to the configuration of the above-described embodiment, and many embodiments can be obtained.

The block diagram which shows the structure of a non-contact communication system. The perspective view which shows the external appearance structure of a scan antenna. The flowchart explaining operation | movement of a non-contact communication system. The block diagram which shows the structure of the non-contact communication system of Example 2. FIG. Explanatory drawing of a timing chart. FIG. 4 is a block diagram illustrating a configuration of a contactless communication system according to a third embodiment. The block diagram which shows the structure of the non-contact communication system of Example 4. FIG. FIG. 9 is a block diagram illustrating a configuration of a contactless communication system according to a fifth embodiment. Explanatory drawing which shows the other structural example of a display. Explanatory drawing which shows the other structural example of a display.

DESCRIPTION OF SYMBOLS 5 ... Non-contact communication apparatus, 10 ... Reader / writer, 11 ... RF transmission / reception part, 15 ... DC power supply, 17 ... Voltage control part, 18 ... RF transmission / reception part for scan control, 20 ... Coaxial cable, 30 ... Scan antenna, 31 ... Antenna unit 32... Phase control unit 37 37 RF rectifier circuit unit 39 RF power detector 40 Control circuit 41 Display

Claims (6)

A directional variable antenna that has an antenna unit that can change the directional direction and performs non-contact communication by the antenna unit, and is connected to the directional variable antenna with a transmission cable to transmit and receive communication signals via the transmission cable. A non-contact communication device including a reader / writer that performs communication control,
The reader / writer includes switching signal transmission means for transmitting a directivity direction switching signal for switching the directivity direction of the antenna unit together with the communication signal through the transmission cable.
The non-contact communication apparatus provided with the antenna operation switching means which detects the said directivity direction switching signal and switches the directivity direction of the said antenna part in the said directivity variable antenna. The non-contact communication apparatus according to claim 1, wherein the reader / writer includes output means for outputting a directivity direction of the antenna unit so that a human can recognize the direction. The switching signal transmitting means is configured to instruct switching of the directing direction by at least one of output ON and output OFF of the communication signal,
The non-contact communication apparatus according to claim 1, wherein the antenna operation switching unit is configured to detect at least one of the output ON and the output OFF and switch a directivity direction of the antenna unit. Power supply means for superimposing a DC voltage on the communication signal between the switching signal transmission means of the reader / writer and the transmission cable,
The antenna operation switching means of the directivity variable antenna;
A power detector for detecting the output of the communication signal;
A phase control unit for controlling a phase of a signal transmitted to the antenna unit;
The non-contact communication apparatus according to claim 3, further comprising a control circuit unit that controls the phase control unit based on at least one of output ON and output OFF of the communication signal detected by the power detection unit. The antenna operation switching means;
A power detector for detecting the output of the communication signal;
A phase control unit for controlling a phase of a signal transmitted to the antenna unit;
A control circuit unit that controls the phase control unit using at least one of output ON and output OFF of the communication signal detected by the power detection unit as the directivity direction switching signal;
The non-contact communication apparatus according to claim 3, further comprising: a DC voltage extraction unit that rectifies a part of a communication signal coming from the transmission cable, extracts a DC voltage, and supplies the DC voltage to each unit. An antenna unit that can change the direction of directivity;
A power detector for detecting the output of a communication signal received from the transmission cable;
A phase control unit for controlling a phase of a signal transmitted to the antenna unit;
A control circuit unit that controls the phase control unit based on at least one of output ON and output OFF of the communication signal detected by the power detection unit;
An antenna apparatus comprising: a DC voltage extraction unit that rectifies a part of a communication signal received from the transmission cable, extracts a DC voltage, and supplies the DC voltage to each unit.

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