JP5149144B2 - Wireless communication system, wireless device, and wireless communication method - Google Patents

Description

  The present invention relates to a wireless communication system, a wireless device, and a wireless communication method for performing wireless communication at a short distance. For example, a wireless communication system, a wireless communication system, and a wireless communication method that easily secure security in wireless communication by controlling a reach of a transmission radio wave. The present invention relates to a device and a wireless communication method.

  Conventionally, in a general authentication system for a wireless portable device (hereinafter referred to as a wireless device), it is necessary to input data such as a preset ID and password. On the other hand, in order to simplify the authentication process by omitting the data input at the time of authentication, the transmission power is controlled and the communication range is narrowed, so that only the desired wireless device transmits and receives necessary signals for authentication. It has been proposed to perform data communication by increasing transmission power after exchanging information and completing exchange of authentication information (see, for example, Patent Documents 1 and 2).

On the other hand, assuming a system with a narrow communication range, such as a long communication range of about several tens of centimeters, there is a possibility that a signal leaks to a so-called third-party wireless device other than the desired wireless device only with transmission power control. high. It is better to exchange authentication information after confirming in advance the signal leakage to the third party's wireless device, but the above patent document does not describe these methods.
Patent No. 366293 JP 2005-323149 A

  The present invention provides a wireless communication system, a wireless device, and a wireless communication method capable of performing communication while suppressing leakage of radio waves to the outside as much as possible.

A wireless communication system as one aspect of the present invention includes:
A first wireless device having a first antenna device in which a first communication antenna is installed inside a first metal housing whose one surface is open;
A second antenna device having a second communication antenna installed in a second metal casing with one side open, and a detection antenna provided around the second metal casing; Wireless devices,
With
The first wireless device is:
A communication request signal is transmitted to the second wireless device via the first communication antenna in a state where the one surface of the first metal housing is close to the one surface of the second metal housing. Including request sending means,
The second wireless device is
Request receiving means for receiving the communication request signal transmitted from the first wireless device via the second communication antenna;
Inspection means for inspecting the reception state of radio waves at the detection antenna when the communication request signal is received;
Response transmission means for transmitting the response signal including the reception state information of the radio wave to the first wireless device via the second communication antenna,
The first wireless device includes a response receiving unit that receives the response signal via the first communication antenna;
Determining means for determining whether to perform wireless communication with the second wireless device based on the reception state information included in the response signal;
A first communication means for performing the wireless communication with the second wireless device via the first communication antenna when it is determined to perform the wireless communication;
The second wireless device includes second communication means for performing wireless communication with the first wireless device via the second communication antenna.
It is characterized by that.

A wireless device as one embodiment of the present invention includes:
An antenna device in which a communication antenna is installed in a metal case that is open on one side;
A detection antenna provided around the metal casing;
Request receiving means for receiving a communication request signal transmitted from another wireless device via the communication antenna;
Inspection means for inspecting the reception state of radio waves at the detection antenna when the communication request signal is received;
A response transmission means for transmitting a response signal including the reception state information of the radio wave to the other wireless device via the communication antenna;
Communication means for performing wireless communication with the other wireless device via the communication antenna;
Is provided.

A wireless device as one embodiment of the present invention includes:
An antenna device in which a communication antenna is installed inside a metal casing that is open on one side;
A communication request signal is sent via the communication antenna to another wireless device in which another communication antenna is installed inside another metal case that is open on one side and a detection antenna is provided around the other metal case. A request transmitting means for transmitting;
Response receiving means for receiving, via the communication antenna, a response signal including reception state information of radio waves at the detection antenna when the communication request signal is received from the other wireless device;
Determining means for determining whether to perform wireless communication with the other wireless device based on the reception state information of the radio wave;
Communication means for performing the wireless communication with the other wireless device via the communication antenna when it is determined to perform the wireless communication;
Is provided.

A wireless communication method as one aspect of the present invention includes:
A first wireless device having a first antenna device in which a first communication antenna is installed inside a first metal housing whose one surface is open;
A second antenna device having a second communication antenna installed in a second metal casing with one side open, and a detection antenna provided around the second metal casing; A wireless communication method performed by a wireless device,
The first and second wireless devices are close to each other so that the one surface of the first and second metal casings face each other;
The first wireless device transmits a communication request signal from the first communication antenna to the second wireless device;
The second wireless device inspects the reception state of the radio wave at the detection antenna when the communication request signal is received by the second communication antenna, and sends a response signal including the reception state information of the radio wave to the first Transmitted to the first wireless device by two communication antennas,
The first wireless device determines whether to perform wireless communication with the second wireless device based on the reception state information included in the response signal received by the first communication antenna, and performs the communication. When it is decided to perform, the wireless communication is performed with the two wireless devices via the first communication antenna.
It is characterized by that.

  According to the present invention, communication can be performed in a state in which leakage of radio waves to the outside is suppressed as much as possible.

  Hereinafter, the present embodiment will be described in detail with reference to the drawings.

(First embodiment)
1 and 2 show a wireless communication system according to a first embodiment of the present invention.

  This wireless communication system includes three wireless devices A to C. FIG. 1 shows a case where wireless devices A and B are sufficiently close to each other and authentication information (information necessary for data encryption (encryption key, etc.)) is transmitted and received between wireless device A and wireless device B. 2 shows a case where data communication is performed based on the authentication information in a state where the wireless devices A and B are slightly separated after the transmission and reception of the authentication information between the wireless devices A and B in FIG. Transmission / reception of authentication information means sending authentication information from one wireless device to the other wireless device. The wireless devices A and B may perform data communication in a close state as shown in FIG.

  FIG. 3 shows a configuration of the antenna device (antenna device with a wall) according to the first embodiment of the present invention.

  This antenna device is configured as a communication antenna (first or second communication antenna) disposed inside a metal casing (first or second metal casing) that is open on one side. More specifically, a communication antenna 200 disposed at a position about a quarter wavelength above the metal plate (ground plate) 101, and a height 2 surrounding the communication antenna 200 and having one end grounded to the metal plate 101 And a metal wall 102 having a wavelength of about 1 / wavelength. The height of the metal wall 102 is the length in the direction perpendicular to the side connected to the metal plate 101. The metal plate 101 and the metal wall 102 form a metal casing. For example, a dielectric is embedded in the metal casing. Here, the metal wall 102 is formed of a plurality of plate-like metals, but is formed by via holes formed at regular intervals (for example, intervals of about 1/10 wavelength or less of the operating frequency) along the outer periphery of the dielectric. May be. One end of the plate-like metal wall 102 means a side, but one end of the metal wall formed by a via hole means the end of the via hole. Conversely, the other end of the metal wall 102 means a side parallel to the side (one end) connected to the base plate in the case of a plate-like metal wall, and in the case of a via hole, the other end facing the end connected to the base plate Means the end. Here, the communication antenna is more generally arranged at a position away from the metal plate 101 by m × λ / 2−λ / 4 (m is an arbitrary integer of 1 or more, and λ is a wavelength of the operating frequency). The metal wall 102 has a height of n × λ / 2 (n is an arbitrary integer greater than or equal to m). The example of FIG. 3 shows an example where m = 1 and n = 1.

  Each of the wireless devices A to C includes this antenna device. The transmitting side and the receiving side communicate with each other using this antenna device. In particular, when communication is performed in close proximity between the transmission side and the reception side, communication is performed such that one surface (open surface) of each antenna device is close to and face each other as shown in FIG.

  The antenna device of FIG. 3 draws a radiation pattern as shown in FIG. 3 and operates as an antenna with a reflector when the transmitting side and the receiving side communicate with each other sufficiently apart. On the other hand, as shown in FIG. 4, if both are arranged at a sufficiently short distance at a desired position, the communication antenna 200 is surrounded by the metal plate 101 and the metal wall 102 of each antenna device. Transmitted radio waves from 200 remain in the space surrounded by the metal plate 101 and the metal wall 102, and leakage outside the wall 102 is prevented. In this state, the distance between the metal plates 101 facing each other in this sealed space is approximately one wavelength of the operating frequency, so that two electric field standing waves are raised, and both communication antennas 200 are located on the antinodes of the standing waves. Therefore, suitable communication performance can be obtained. At this time, since the contact surface between the metal walls 102 is located at the node of the standing wave, even if the contact position slightly deviates in the direction parallel to the ground plane, the radio wave leaking outside is small. Such a relationship between the antinodes and the nodes is maintained as long as the above-described antenna element height constraint and metal wall height constraint are satisfied.

  In this way, if authentication information is sent and received when there is no external leakage as shown in Fig. 4, higher security can be obtained than when communication is performed by narrowing the communication range by conventional transmission power control. Can do. That is, suitable communication with small information leakage can be performed, and communication of authentication information can be performed safely. However, when actually transmitting / receiving authentication information, it is determined whether the transmitting device and the receiving device having the antenna device are disposed at a sufficiently short distance at a desired position, that is, outside the desired range. It is necessary to judge correctly whether there is no radio wave leakage.

  Therefore, in the present embodiment, in order to enable such a determination, an antenna for detecting radio wave leakage (detection antenna) is arranged around the wall 102 of the wall-mounted antenna device shown in FIG.

  FIG. 5 shows an example in which four detection antennas are arranged around the wall 102 of the wall-mounted antenna device.

  The detection antennas 1 to 4 are arranged outside the wall 102 of the antenna apparatus with a wall, and it is assumed that there is a radio wave leakage state while the detection antennas 1 to 4 detect a radio wave having a reception level equal to or higher than a threshold value. During the state, a secret signal (for example, authentication information) that is desired to be transmitted / received only by two desired wireless devices is not transmitted / received. In FIG. 5, a wall 102 is arranged around the communication antenna 200 so that a rectangular open surface is formed in a plan view. However, the shape of the open surface is not limited to the shape of this figure, and is circular. But other shapes are no problem. Further, the detection antennas 1 to 4 may be elements having simpler elements than the communication antenna used for the communication, as long as radio wave leakage can be detected.

  In addition, since the wall-mounted antenna device draws a radiation pattern as shown in FIG. 3, if the detection antenna is arranged at a long distance from the wall of the wall-mounted antenna device, there is a high possibility that it cannot be detected despite radio wave leakage. . Therefore, the detection antenna is disposed at a short distance from the wall of the wall-mounted antenna device. In addition, the number of detection antennas to be arranged is likely to cause the wall-mounted antenna device to shift in any direction parallel to the surface of the metal plate 101 when trying to match open surfaces close to each other as shown in FIG. If is high, 4 or more is desirable. On the other hand, for example, when a card (wireless device) having a wall-mounted antenna device is held over a card reader or the like, if the card reader supports the card in one direction, the one direction Deviation in the direction is physically suppressed, and deviation in the other direction becomes a problem. In such an application, the number of detection antennas may be two. In the above description, two examples in which the number of detection antennas is four and two have been described. However, the number of detection antennas according to the present proposal is not limited to the above number.

  FIG. 6 is a block diagram showing a configuration example of the wireless device according to the first embodiment of the present invention.

  This wireless device includes at least a wall antenna apparatus 10 for communication, two detection antennas 20, an RF (Radio Frequency) unit 30, a detection RF unit 40, and a digital unit 50. The digital unit 50 includes a transmission unit 51, a reception unit 52, and a radio wave leakage management unit 53. The transmission unit 51 and the reception unit 52 are connected to an upper layer processing unit (not shown) to control transmission signals and reception signals. Hereinafter, the operation of each element in the wireless device will be described in detail with reference to FIG.

  FIG. 7 shows a sequence of processes performed in the wireless devices A and B from when the wireless devices A and B having the configuration of FIG. 6 start connection, transmit and receive authentication information, and start transmitting and receiving data. It is a chart. Hereinafter, a case where the user A of the wireless device A brings the wireless device A close to the wireless device B fixedly installed and requests connection from the wireless device A to the wireless device B will be described as an example.

  First, the wireless device A requesting a connection makes a connection request signal in a state where the open surface of the metal housing of the antenna device of the wireless device A is close to the open surface of the metal housing of the antenna device of the wireless device B. A (communication request signal) is transmitted from the transmission unit 51 via the RF unit 30 and the wall-mounted antenna device 10 (S11). Therefore, the transmission unit 51 of the wireless device A includes request transmission means for transmitting a connection request signal (communication request signal) to the wireless device B via the communication antenna of the wall-mounted antenna device 10. In the present embodiment, the wireless device A knows the address of the wireless device B in advance, transmits the connection request signal after designating the address as the destination address. Note that the processing when the destination address is not designated will be described in the second embodiment.

  On the other hand, in the wireless device B, the connection request signal transmitted from the wireless device A is received by the receiving unit 52 via the antenna device 10 and the RF unit 30. Therefore, the receiving unit 52 of the wireless device B includes request receiving means for receiving the connection request signal transmitted from the wireless device A via the communication antenna.

  The receiving unit 52 of the wireless device B determines whether or not the destination address of the connection request signal is for itself. When it is determined that the destination of the connection request signal is addressed to itself, the reception unit 52 notifies the transmission unit 51 to that effect, and the transmission unit 51 creates a connection response signal.

  At the same time, in the radio wave leakage management unit 53, based on the signal from the RF unit 40 connected to each detection antenna 20, the presence or absence of radio wave leakage to each detection antenna 20 (that is, whether the reception level is equal to or higher than a threshold), Then, the magnitude of the radio wave leakage (reception level) is calculated and notified to the transmission unit 51 (S12). Therefore, the radio wave leakage management unit 53 includes inspection means for inspecting the reception state of radio waves such as the presence or absence of radio wave leakage in the detection antenna 20 and the magnitude of radio wave leakage when the connection request signal is received.

  The transmission unit 51 of the wireless device B inserts the presence / absence of the radio wave leakage notified from the radio wave leakage management unit 53 and the magnitude of the radio wave leakage into the connection response signal for transmission (S13). Therefore, the transmission unit 51 of the wireless device B includes a response transmission unit that transmits a connection response signal including the reception state information of the radio wave detected by the radio wave leakage management unit 53 to the wireless device A via the communication antenna.

  Here, the presence / absence of radio wave leakage and the magnitude of radio wave leakage are included in the connection response signal, but either one of these signals may be inserted into the connection response signal. Alternatively, the signal different from these may include, for example, an authentication information transmission permission or non-permission signal (a signal indicating whether communication is permitted). The information on the presence / absence of radio wave leakage, the information on the magnitude of radio wave leakage, and the information indicating whether or not to allow communication correspond to the radio wave reception state information (radio wave leakage information) of the present invention. The reception status information is defined as information that can be used to determine whether or not short-range communication is performed between the wireless devices A and B. The transmission unit 51 transmits the connection response signal including the reception state information.

  On the other hand, the wireless device A enters a reception standby state after transmitting the connection request signal in S11, and thereafter receives the connection response signal from the wireless device B at the receiving unit 52 via the antenna device 10 and the RF unit 30. Accordingly, the receiving unit 52 of the wireless device A includes response receiving means for receiving a connection response signal via the communication antenna of the antenna device 10. The receiving unit 52 of the wireless device A confirms the information (radio wave reception state information) described in the received connection response signal (S14), and whether there is radio wave leakage (that is, whether to communicate with the wireless device B) Or). Therefore, the receiving unit 52 of the wireless device A includes a determination unit that determines whether or not there is a radio wave leakage (that is, whether or not to communicate with the wireless device B) based on the reception state information of the radio wave. Here, “there is no radio wave leakage” means that the reception level of each detection antenna is less than the threshold value, for example. If it can be determined that there is no radio wave leakage, the authentication information is sent from the reception unit 52 to the transmission unit 51, and the transmission unit 51 transmits the authentication information via the RF unit 30 and the wall-mounted antenna device 10 (S15). Alternatively, the wireless device A may receive the authentication information from the wireless device B at the receiving unit 52 via the wall-mounted antenna device 10 and the RF unit 30 instead of sending the authentication information to the wireless device B.

  After that, when receiving a response signal (denoted as ACK signal in the figure) for the transmission of the authentication information (S16), the reception A is a trigger, and the user A places the wireless device A slightly away from the wireless device B ( Release the contact (S17) and exchange data signals (S18). For example, the data is encrypted with an encryption key and transmitted based on the authentication information, or the encrypted data is received and decrypted based on the authentication information.

  As can be understood from the description of S15 to S18, the wireless device A communicates with the wireless device B via the communication antenna via the first communication means (receiving unit 52 and transmitting unit 51) that performs wireless communication such as authentication information or data signal. The wireless device B includes second communication means (receiving unit 52 and transmitting unit 51) for performing wireless communication such as authentication information or data signal with the wireless device A via the communication antenna.

  In step S14, if radio wave leakage is confirmed, the wireless device A that has transmitted the connection request does not transmit authentication information, and the user A moves the wireless device A and then sends a connection request signal from the wireless device A. resend.

  Here, a specific method for confirming the presence / absence of radio wave leakage and the magnitude of radio wave leakage by the radio wave leakage management unit 53 in step S12 will be described. That is, a method for measuring the reception state of radio waves such as the presence / absence of radio wave leakage in radio device B and the magnitude of radio wave leakage when a connection request signal is received from radio device A will be specifically described.

  The radio wave leakage management unit 53 periodically checks the presence / absence of radio wave leakage (whether the reception level is equal to or higher than a threshold) and the magnitude of the radio wave leakage based on the received signal input from the detection antenna 20 via the RF unit 40. The test result is held in association with the input time of the received signal. When receiving the notification that the connection request signal has been received from the receiving unit 52, the radio wave leakage management unit 53 confirms the inspection result of the input time corresponding to the time when the notification is received. The radio wave leakage management unit 53 may use the inspection result of the input time corresponding to the time before a certain period from when the notification indicating that the connection request signal is received. Further, the radio wave leakage management unit 53 may be notified of the reception time of the connection request signal from the reception unit 52, and this reception time may be used instead of the time when the notification is received.

  As another method, a means for inspecting the presence / absence of radio wave leakage and the magnitude of radio wave leakage is arranged on the detection antenna 20 side, and the radio wave leakage management unit 53 is periodically notified of the inspection result from the means. May store the inspection results sent periodically in association with the notification time of the inspection results. In this case, when receiving the notification that the connection request signal has been received from the receiving unit 52, the radio wave leakage management unit 53 confirms the test result corresponding to the time when the notification is received. The radio wave leakage management unit 53 may use the inspection result of the input time corresponding to the time before a certain period from when the notification indicating that the connection request signal is received. Alternatively, the reception unit 52 may be notified of the reception time of the connection request signal, and this reception time may be used instead of the time when the notification is received. In addition, the detection antenna 20 notifies the radio wave leakage management unit 53 of the start time and end time of the radio wave leakage, and the radio wave leakage management unit 53 has a radio wave leakage if the notified time is between the start time and the end time. You may judge.

  As described above, according to the first embodiment, the antenna for detecting radio wave leakage is arranged around the wall of the antenna device with a wall, and transmission / reception of a secret signal (authentication information, etc.) that is desired to be shared only between desired wireless devices. Before detecting radio leaks and sending and receiving the confidential signal only when there is no radio leaks, authentication with the radio leaks to the outside reliably suppressed (with increased security) It becomes possible to transmit and receive confidential signals such as information. In the case of transmission / reception other than a confidential signal such as authentication information, transmission / reception can be performed even when the transmission device and the reception device are separated.

(Second embodiment)
In the first embodiment, the connection request signal is transmitted by specifying the destination address of the connection partner as the destination address of the connection request signal. On the other hand, in the second embodiment, the destination address of the connection request signal is transmitted as a broadcast address without specifying a specific wireless device. In this way, communication can be started without knowing the address of the counterpart device in advance.

  FIG. 8 is a sequence chart showing a sequence of processing performed by the wireless devices A and B from when the wireless devices A and B start connection, transmit and receive authentication information, and start transmitting and receiving data according to the present embodiment. It is.

The wireless device A requesting connection transmits a connection request signal specifying a broadcast address as a destination address from the transmission unit 51 via the RF unit 30 and the wall-mounted antenna device 10 (S21).
When receiving the connection request signal whose destination address is the broadcast address, the RF unit 30 of the wireless device B that has received the connection request signal notifies the transmission unit 51 and creates a connection response signal in the transmission unit 51. . At the same time, based on the signal from the RF unit 40 connected to the detection antenna 20, the presence or absence of radio wave leakage to the detection antenna in the radio wave leakage management unit 53 (whether the reception level of the detection antenna is equal to or higher than a threshold), Then, the magnitude of the radio wave leakage (the reception level of the detection antenna) is calculated and notified to the transmission unit 51 (S22). The transmission unit 51 inserts the presence / absence of radio wave leakage notified from the radio wave leakage management unit 53 and the magnitude of the radio wave leakage into the connection response signal and transmits it.

  The connection request signal transmitted from the wireless device A can be received by peripheral wireless devices other than the wireless device B depending on the contact status with the desired wireless device B, and a connection response signal can also be received from the peripheral wireless device. There is sex. In the example of FIG. 8, the connection request signal is also received by the wireless device C, and the connection response signal is returned from the wireless device C to the wireless device A (S23, S25). In such a case, the wireless device A specifies a desired wireless device (a nearby wireless device) from the received power intensity (reception level) of each connection response signal or the magnitude of radio wave leakage.

  The magnitude of radio wave leakage seems to have a larger difference between the desired wireless device and other wireless devices than the received power intensity, but in this embodiment, even if judgment is made using either one of the above information Alternatively, the determination may be made using both information. For example, the wireless device A compares the received signal strengths of the connection response signals, and designates the wireless device having the maximum received power strength as the desired wireless device. Alternatively, the maximum value of the detection antenna reception level is specified for each wireless device, the maximum values between the wireless devices are compared, and the wireless device with the minimum maximum value (that is, the wireless device with the minimum radio wave leakage) is the desired wireless device. Specify as. As described above, when a plurality of connection response signals are received, the wireless device A selects the wireless device that has transmitted the connection response signal having the maximum reception level as a desired wireless device. Alternatively, the wireless device A selects a wireless device that has transmitted reception state information describing the lowest detection antenna reception level as a desired wireless device.

The subsequent sequence is the same as in the first embodiment. That is, if the radio wave leakage status (reception status information) described in the connection response signal from the specified wireless device is confirmed and it can be determined that there is no radio wave leakage, the authentication information is directed to the destination address of the specified wireless device. (S27). When the response signal is received from the designated wireless device (S28), the wireless device A is slightly separated from the proximity state (S29), and the data signal is transmitted / received (S30).
In the above description, the wireless device A has identified a desired wireless device by analyzing connection response signals from a plurality of wireless devices, but the connection response signal is received from the wireless devices B and C that have received the connection request signal. They are transmitted at the same timing, and they may collide. Therefore, the wireless devices B and C that have received the connection request signal determine whether they are the desired wireless device from the radio wave leakage state, and transmit the connection response signal only when it can be determined that it is the desired wireless device. It may be. For example, each of the wireless devices B and C checks whether or not the maximum value of the reception level of the detection antenna is greater than or equal to a threshold value. Send. As a result, the wireless device A receives the connection response signal from only one of the wireless devices B and C, and therefore, processing may be performed according to the above-described sequence based on the radio wave leakage state described in the received connection response signal. .

  As described above, according to the second embodiment, there is no need to perform a so-called association operation such as transmission / reception of an address signal or the like with a counterpart device before transmission of a connection request signal. The sequence between them can be reduced. In addition, since the wireless device that has received the connection request signal determines whether it is the desired wireless device from the radio wave leakage state, the wireless device that transmits the connection response signal is limited. The possibility that the response signals collide can be greatly reduced.

(Third embodiment)
FIG. 9 is a block diagram illustrating a configuration example of a wireless device according to the third embodiment. Below, it demonstrates centering on the difference with 1st and 2nd embodiment.

  A power management unit 54 is newly provided for the block diagram of FIG. Under the control of the power management unit 54, power supply to the RF unit 40 and the radio wave leakage management unit (inspection means) 53 connected to the detection antenna 20 is stopped during standby. The RF unit 40 and the radio wave leakage management unit 53 form a radio wave leakage detection block.

  When the signal is received by the receiving unit 52, the receiving unit 52 determines whether or not the received signal is a connection request signal, and in the case of the connection request signal, determines whether or not the destination address is addressed to itself or broadcast. . When the connection request signal and the destination address are addressed to itself or the broadcast address, the receiving unit 52 sends a start request signal to the power management unit 54, and the power management unit 54 that has received the start request signal connects to the detection antenna 20. The power supply to the RF unit 40 and the radio wave leakage management unit (inspection means) 53 to be started is started. In addition, the receiving unit 52 notifies the transmitting unit 51 that the connection request signal has been received and that the function of the radio wave leakage detection block has been turned off, and the transmitting unit 51 has not yet performed the radio wave leakage inspection. A connection response signal including information indicating that the communication request has not been received (information on radio wave leakage non-inspection information) is created, and the created connection response signal is notified to the wireless device that has transmitted the connection request signal. The response signal including the radio wave leakage non-inspection information corresponds to, for example, a retransmission request signal for requesting retransmission of the connection request signal, and the transmission unit 51 includes retransmission processing means for transmitting the retransmission request signal. Note that the power supply management unit 54 may stop the power supply of the transmission unit 51 other than the above during standby.

  The wireless device that has received the connection response signal including the radio wave leakage non-inspection information retransmits the connection request signal. The wireless device that has received the connection request signal detects the presence or absence of radio wave leakage, etc., because the radio wave leakage detection block (RF unit 40 and radio wave leakage management unit 53) is activated at the time of reception. Attached to connection response signal. Since this process is the same as the method described in the first embodiment, the description thereof is omitted here.

  When the data communication is completed, for example, the receiving unit 52 notifies the power management unit 54 of a stop signal, and the power management unit 54 stops the power supply to the RF unit 40 and the radio wave leakage management unit 53 connected to the detection antenna 20. To do.

  In the above operation, when the radio wave leakage detection block is OFF when the first connection request signal is received, a connection response signal (retransmission request signal) including radio wave leakage non-inspection information is transmitted. A configuration in which a connection response signal (retransmission request signal) is not transmitted may be employed. In that case, the wireless device that has transmitted the connection request signal retransmits the connection request signal when a response to the wireless device does not return within a certain time. When the retransmitted connection request signal is received, the radio wave leakage detection block is on (ON), and the above-described operation may be performed. Accordingly, the transmission unit 51 includes a retransmission processing unit that waits for retransmission of the connection request signal without transmitting the retransmission request signal.

  As described above, the retransmission processing means included in the transmission unit 51 of the wireless device may be configured to wait for retransmission of the connection request signal, or return a connection response signal (retransmission request signal) including radio wave leakage non-inspection information. You may comprise as follows.

  In the first and second embodiments, the radio wave detection block (the RF unit 40 and the radio wave leakage management unit 53) is always in an operating state, but in the third embodiment, the radio wave detection block is only necessary. , And the power of the radio wave detection block is turned off during standby, so that power consumption during standby can be suppressed.

(Fourth embodiment)
FIG. 10 is a block diagram illustrating a configuration example of a wireless device according to the fourth embodiment.

  Similar to the third embodiment, the wireless device includes a power management unit 54. The power management unit 54 stops the power supply to the RF unit 30 for signal transmission / reception, the transmission unit (response transmission unit, communication unit) 51, and the reception unit (request reception unit, communication unit) 52 during standby. That is, in the third embodiment, power supply to the radio wave leakage detection block (RF unit 40 and radio wave leakage management unit 53) is stopped during standby, but in this embodiment, only the radio wave leakage detection block is used during standby. Start up.

  A signal (for example, a beacon signal periodically transmitted) transmitted from a wireless device while approaching to transmit a connection request signal is transmitted to the RF unit 40 and the radio wave leakage management unit 53 connected to the detection antenna 20. Then, the radio wave leakage management unit 53 calculates the magnitude of the radio wave leakage. As a result, if it is determined that there is a received radio wave based on the threshold judgment (when a radio wave with a magnitude greater than a certain value is detected), it is assumed that there is at least a signal from a nearby wireless device, and an activation request is sent to the power management unit 54 Send a signal.

  Upon receiving the activation request signal, the power management unit 54 starts supplying power to the RF unit 30 for signal transmission / reception, the transmission unit (response transmission unit, communication unit) 51, and the reception unit (request reception unit, communication unit) 52. . In addition, for example, when calculating the magnitude of radio wave leakage, if it is determined that the magnitude of radio wave leakage is gradually decreasing, wait for the radio wave leakage to become less than the threshold and use it as a trigger for the power management unit. A mechanism for notifying the activation request signal to 54 may be adopted.

  In general, compared with an RF unit and a communication antenna used for signal transmission / reception, the detection RF unit and the detection antenna are often made simple and suppress power consumption. Therefore, as in the present embodiment, by activating only the detection RF unit and the detection antenna during standby, the power consumption can be further reduced as compared with the third embodiment.

(Fifth embodiment)
In this embodiment, at the time of radio wave leakage inspection, by specifying the direction of radio wave leakage and notifying the other device in addition to the presence or absence of radio wave leakage and the magnitude of the radio wave leakage, the other device has a large radio wave leakage and authentication information A case will be described in which the position adjustment of the counterpart device is assisted when it is determined that transmission is impossible.

  For example, when the detection antennas 1 to 4 are arranged around the antenna device with a wall as shown in FIG. 5, the detection antenna 1 in the wireless device has detected radio wave leakage (the reception level is equal to or higher than the threshold value). It is assumed that the detection antennas 2 to 4 did not detect radio wave leakage (the reception level is less than the threshold value). In this case, there is a high possibility that the antenna device with a wall of the counterpart wireless device is displaced downward along the paper surface. Therefore, when the wireless device transmits a connection response signal to the counterpart wireless device, the wireless device also notifies that the shift is downward. That is, the radio wave leakage management unit (inspection means) 53 of the wireless device determines the direction of radio wave leakage based on the relationship between the detection antenna that has detected a reception level that is equal to or greater than the threshold and the detection antenna that has detected a reception level that is less than the threshold. And a value indicating the direction of radio wave leakage (or the opposite direction) is included in the connection response signal transmitted by the transmission unit 51. As a result, the user of the wireless device that has received the connection response signal moves the wireless device slightly upward, and tries again to transmit the connection response signal from the wireless device. In this way, based on the relationship between the detection antenna that has detected a reception level that is greater than or equal to the threshold and the detection antenna that has detected a reception level that is less than the threshold, the direction of deviation (or radio leakage that is opposite to the direction of deviation). Direction).

  However, in order to do this, it is necessary to notify the counterpart device in advance of the position (direction) of at least one of the plurality of detection antennas (here, the detection antenna 1). For this purpose, for example, the wireless device trial-transmits a signal from the detection antenna 1 before returning a connection response. That is, the transmission unit 51 of the wireless device includes a signal transmission unit that transmits a signal from the detection antenna 1 that is at least one of the plurality of detection antennas.

  In the radio wave leakage management unit (inspection means) 53 of the counterpart device, the direction of the detection antenna 1 of the wireless device is specified from the reception level of the signal at each of the detection antennas 1 to 4, and the direction of the specified detection antenna 1 And the direction of each detection antenna of the wireless device (or the direction of each detection antenna of its own device) from the predetermined reference. That is, the radio wave leakage management unit (inspection unit) 53 of the counterpart device receives the signal transmitted from the signal transmission unit of the wireless device via each of the detection antennas 1 to 4 and the RF unit 40, and based on each received signal Specific means for specifying the direction of each detection antenna of the wireless device is provided. For example, when the highest reception level is detected by the detection antenna 3 among the detection antennas 1 to 4 of the counterpart device, the direction of the detection antenna 3 of the counterpart device and the direction of the detection antenna 1 of the wireless device are If they match, the receiving unit 52 of the counterpart device determines. Then, the counterpart device uses the detection antenna 1 to 1 of the wireless device based on a predetermined reference (for example, clockwise) with reference to the direction of the detection antenna 1 of the wireless device (or the direction of the detection antenna 3 of the own device). 4 directions (or directions of the detection antennas 1 to 4 of the own device) are determined.

  In addition, in order to display the notified direction in a form that is understandable to the user, for example, LEDs (indicator lamps) are mounted on each device, for example, in the direction you want to move, that is, the direction of the radio wave leakage (the direction opposite to the deviation direction) It is conceivable to blink the (display lamp). In addition, the wireless device is provided with an LED (indicator lamp) in each direction, and the radio device of the wireless device that has received the connection request signal without notifying the other device of the deviation direction from the wireless device that has received the connection request signal. The leakage management unit (inspection means) 53 blinks the LED (indicator lamp) in the direction of radio wave leakage (opposite the direction of deviation), and the direction that the user wants to move, that is, the direction of radio wave leakage (deviation) It is also possible to display the opposite direction).

  As described above, in the fifth embodiment, at the time of radio wave leakage inspection, in addition to the presence or absence of radio wave leakage and the magnitude of radio wave leakage, it is possible to easily avoid the state of radio wave leakage by notifying the direction of radio wave leakage. I can do it.

(Sixth embodiment)
In the first to fifth embodiments, when there is radio wave leakage, a mechanism for eliminating radio wave leakage and a case where transmission of authentication information is refrained are shown. On the other hand, in the present embodiment, a case will be described in which, when there is a radio wave leak, transmission / reception of a signal that may be leaked to a third party is performed instead of refraining from communication.

  Depending on the type of signal to be transmitted / received or the environment around the wireless device performing the transmission / reception, the selection of whether to refrain from communication when there is radio wave leakage or to continue communication is different. For example, when it is desired to perform personal exchanges such as e-mails, it is preferable to refrain if there is a radio wave leak, but there may be a case where transmission / reception is possible even if there is a slight radio wave leak such as TV video distribution. In addition, for example, when it is known that there is no other device in the vicinity, for example, by performing a peripheral scan in advance, there may be some radio wave leakage.

  FIG. 11 is a sequence chart showing a sequence of processes performed by the wireless devices A and B from when the wireless devices A and B start connection, transmit and receive authentication information, and start transmitting and receiving data according to the present embodiment. It is.

  When wireless device B receives the connection request signal from wireless device A (S41) and performs a radio wave leak check (S42), if there is a radio wave leak (a reception level above the threshold is detected by one of the detection antennas) If there is a radio wave), the connection response signal notifies that there is radio wave leakage and the magnitude of the radio wave leakage (S43).

  On the other hand, the wireless device A that has received the connection response signal determines whether or not to execute transmission of the data signal based on the type of the signal to be transmitted or (and) the surrounding environment of the partner (wireless device B) that performs transmission / reception. Then, the radio wave leakage management unit (type determination means, peripheral inspection means) 53 makes the determination (S44). The radio wave leakage management unit 53 includes a type determination unit that determines the type of data to be transmitted, and a peripheral inspection unit that monitors the wireless channel and checks for the presence of peripheral devices.

  For example, if it is determined that there is radio leak from the connection response signal, but the magnitude of the radio leak is less than or equal to a threshold (greater than the threshold in S42), depending on the type of transmission signal determined by the type determination means Thus, it is determined that the signal leakage is acceptable (for example, a TV signal), and the wireless device A transmits / receives a data signal without transmitting / receiving the authentication information (S45).

  Further, although it is determined from the connection response signal that there is radio leakage, the peripheral inspection means determines that there are no other wireless devices in the vicinity (for example, the radio leakage management unit 53 monitors the wireless channel via the detection antenna, If it is determined that the reception level of the wireless channel is equal to or lower than the threshold value, the wireless device A transmits / receives the data signal without transmitting / receiving the authentication information (S45). Alternatively, the authentication information may be transmitted, and then data may be encrypted based on the authentication information for transmission / reception.

  Furthermore, when the type of the transmission signal matches the predetermined type by the type determination unit, the data signal is transmitted by the communication unit (the transmission unit 51 and the reception unit 52) regardless of the determination result (presence / absence of radio wave leakage) of the determination unit. May be sent and received. Alternatively, when the type of the transmission signal matches a predetermined type, the signal leakage determination by the signal leakage management unit 53 may be omitted and the data signal may be transmitted / received.

In addition, when it is determined by the peripheral inspection means that there is no peripheral device, the communication means (the transmission unit 51 and the reception unit 52) transmits and receives data signals regardless of the determination result (the presence or absence of radio wave leakage) of the determination means. You may go. Alternatively, when it is determined that there is no peripheral device, the signal leakage determination itself by the signal leakage management unit 53 may be omitted and data signals may be transmitted and received.
Thus, in the sixth embodiment, transmission signals can be transmitted and received as necessary in consideration of the type of transmission signal and the surrounding environment of the wireless device even in a situation where there is radio wave leakage.

  In the first to sixth embodiments described so far, the description has been made based on the configuration of a wireless device including only one communication antenna that performs transmission / reception. However, a wireless device in which a plurality of communication antennas that perform transmission / reception are arranged is used. Even if it is used, it is clear that each embodiment can be applied. In that case, for example, as shown in FIG. 12, one detection antenna 2 may be shared by adjacent wall-mounted antenna devices.

  Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, some components may be deleted from all the components shown in the embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

The block diagram of the radio | wireless communications system provided with radio | wireless apparatus AC based on the 1st Embodiment of this invention. FIG. 2 is a diagram showing a state in which wireless devices A and B are separated in FIG. The lineblock diagram of the antenna with a wall concerning a 1st embodiment of the present invention. The figure which shows the state which piled up the antenna with two walls facing each other. The figure which shows the example of arrangement | positioning of the antenna for electric wave leak detection. The figure which shows the structural example of the radio | wireless apparatus which concerns on the 1st Embodiment of this invention. The sequence chart which concerns on the 1st Embodiment of this invention. 6 is a sequence chart according to the second embodiment of the present invention. FIG. 9 is a diagram illustrating a configuration example of a wireless device according to a third embodiment of the present invention. FIG. 9 is a diagram illustrating a configuration example of a wireless device according to a fourth embodiment of the present invention. 10 is a sequence chart according to the sixth embodiment of the present invention. The figure which shows the example of arrangement | positioning of the antenna for a detection in case two or more antennas with a wall exist.

Explanation of symbols

A, B, C: Wireless device 101: Metal plate 102: Metal wall 200: Communication antennas 1-4: Antenna for detection 10: Antenna device 20: Antenna for detection 30: RF unit 40: RF unit 50: Digital unit 51: Transmission unit 52: Reception unit 53: Radio wave leakage management unit 54: Power supply management unit

Claims (20)

A first wireless device having a first antenna device in which a first communication antenna is installed inside a first metal housing whose one surface is open;
A second antenna device having a second communication antenna installed in a second metal casing with one side open, and a detection antenna provided around the second metal casing; Wireless devices,
With
The first wireless device is:
A communication request signal is transmitted to the second wireless device via the first communication antenna in a state where the one surface of the first metal housing is close to the one surface of the second metal housing. Including request sending means,
The second wireless device is
Request receiving means for receiving the communication request signal transmitted from the first wireless device via the second communication antenna;
Inspection means for inspecting the reception state of radio waves at the detection antenna when the communication request signal is received;
Response transmission means for transmitting the response signal including the reception state information of the radio wave to the first wireless device via the second communication antenna,
The first wireless device includes a response receiving unit that receives the response signal via the first communication antenna;
Determining means for determining whether to perform wireless communication with the second wireless device based on the reception state information included in the response signal;
A first communication means for performing the wireless communication with the second wireless device via the first communication antenna when it is determined to perform the wireless communication;
The second wireless device includes second communication means for performing wireless communication with the first wireless device via the second communication antenna.
A wireless communication system. The first communication unit of the first wireless device transmits or receives authentication information necessary for data encryption with the second communication unit of the second wireless device,
Thereafter, the data is encrypted based on the authentication information and transmitted to the second wireless device, or the encrypted data is received from the second wireless device and the received data signal is decrypted based on the authentication information.
The wireless communication system according to claim 1. The first wireless device includes a plurality of second detection antennas provided around the first metal casing,
A plurality of the detection antennas are provided around the second metal casing,
The second wireless device includes signal transmission means for transmitting a signal from at least one of the plurality of detection antennas,
The first wireless device receives a signal transmitted from the signal transmission unit via the plurality of second detection antennas, and specifies a direction of each detection antenna based on a reception level of the signal Including
The inspection unit of the second wireless device detects a detection antenna that detects a reception level that is equal to or greater than the threshold and a detection level that is less than the threshold when there is a detection antenna whose reception level is equal to or greater than the threshold. The radio communication system according to claim 1 or 2, wherein a direction of radio wave leakage is specified based on a relationship with an antenna, and a value indicating the radio wave leakage direction or the opposite direction is included in the response signal. A plurality of the detection antennas are provided around the second metal casing,
The second wireless device includes a display lamp corresponding to each of a plurality of directions,
The inspection unit of the second wireless device detects a detection antenna that detects a reception level that is equal to or greater than the threshold and a detection level that is less than the threshold when there is a detection antenna whose reception level is equal to or greater than the threshold. The radio communication system according to claim 1 or 2, wherein a direction of radio wave leakage is specified based on a relationship with an antenna, and a display lamp corresponding to the radio wave leakage direction or the opposite direction is turned on. The first antenna device is:
A first ground plane;
The first communication antenna disposed at a position away from the first ground plane by m × λ / 2−λ / 4 (m is an arbitrary integer greater than or equal to 1 and λ is a wavelength of an operating frequency);
A first metal wall having a height of n × λ / 2 (n is an arbitrary integer greater than or equal to n), which surrounds the first communication antenna and has one end connected to the first ground plane. Including
The set of the first ground plane and the first metal wall corresponds to the first metal casing with the one surface released,
The second antenna device is
A second ground plane;
The second communication antenna disposed at a position away from the second ground plane by m × λ / 2−λ / 4 (m is an arbitrary integer of 1 or more, λ is a wavelength of an operating frequency);
A second metal wall having a height of n × λ / 2 (n is an arbitrary integer greater than or equal to n), which surrounds the second communication antenna and has one end connected to the second ground plane. Including
The set of the second ground plane and the second metal wall corresponds to the second metal casing in which the one surface is released. 5. Wireless communication system. An antenna device in which a communication antenna is installed in a metal case that is open on one side;
A detection antenna provided around the metal casing;
Request receiving means for receiving a communication request signal transmitted from another wireless device via the communication antenna;
Inspection means for inspecting the reception state of radio waves at the detection antenna when the communication request signal is received;
A response transmission means for transmitting a response signal including the reception state information of the radio wave to the other wireless device via the communication antenna;
Communication means for performing wireless communication with the other wireless device via the communication antenna;
Wireless equipment equipped with. The request receiving means receives the communication request signal specifying a broadcast address as a destination address,
The response transmission means does not transmit the response signal when the reception level of the radio wave is greater than or equal to a threshold value, and transmits the response signal when the reception level of the radio wave is less than the threshold value. The wireless device described. Power management means for stopping power supply to the inspection means during standby and supplying power to the inspection means when the communication request signal specifying the address of the wireless device or a broadcast address as a destination address is received;
A retransmission processing means for transmitting a retransmission request signal for requesting retransmission of the communication request signal or waiting for retransmission of the communication request signal when power is supplied to the inspection means;
The wireless device according to claim 6, further comprising: When the request receiving means, the response transmitting means, and the communication means are turned off during standby, and the inspection means detects a radio wave having a magnitude greater than a certain value, the request receiving means, the response transmitting means, the communication The wireless device according to claim 6, further comprising power management means for supplying power to the means. The antenna device is
With the main plate,
The communication antenna disposed at a position away from the ground plane by m × λ / 2−λ / 4 (m is an arbitrary integer of 1 or more, λ is a wavelength of an operating frequency);
A metal wall having a height of n × λ / 2 (where n is an arbitrary integer equal to or greater than m), which surrounds the communication antenna and has one end connected to the ground plane.
The wireless device according to any one of claims 6 to 9, wherein a set of the base plate and the metal wall corresponds to the metal casing in which the one surface is released. An antenna device in which a communication antenna is installed inside a metal casing that is open on one side;
A communication request signal is sent via the communication antenna to another wireless device in which another communication antenna is installed inside another metal case that is open on one side and a detection antenna is provided around the other metal case. A request transmitting means for transmitting;
Response receiving means for receiving, via the communication antenna, a response signal including reception state information of radio waves at the detection antenna when the communication request signal is received by the other communication antenna from the other wireless device;
Determining means for determining whether to perform wireless communication with the other wireless device based on reception state information of the radio wave at the detection antenna when the communication request signal is received by the another communication antenna ;
Communication means for performing the wireless communication with the other wireless device via the communication antenna when it is determined to perform the wireless communication;
Wireless equipment equipped with. The reception state information includes a magnitude relationship between a reception level and a threshold value, or a magnitude of the reception level. The determination unit determines to perform the wireless communication when the reception level is equal to or less than the threshold value. The wireless device according to claim 11, characterized in that: Further comprising a type determining means for determining the type of data to be transmitted to the other wireless device;
When the data type matches a predetermined type, the communication unit performs the wireless communication with the other wireless device via the communication antenna regardless of the determination result of the determination unit. The wireless device according to claim 11 or 12. Further comprising a type determining means for determining the type of data to be transmitted to the other wireless device;
The determination means omits the determination when the data type matches a predetermined type,
The wireless device according to claim 11 or 12, wherein the communication unit performs the wireless communication with the other wireless device via the communication antenna. Peripheral inspection means to monitor the wireless channel and inspect for peripheral devices,
The communication means, when it is determined that there is no peripheral device, performs the wireless communication with the other wireless device via the communication antenna regardless of the determination result of the determination means. Item 13. The wireless device according to Item 11 or 12. Peripheral inspection means to monitor the wireless channel and inspect for peripheral devices,
The determination means omits the determination when it is determined that there is no peripheral device,
The wireless device according to claim 11 or 12, wherein the communication unit performs the wireless communication with the other wireless device via the communication antenna. The request transmission means transmits the communication request signal designating a broadcast address as a destination address,
When the response receiving unit receives the response signal from a plurality of the other wireless devices, the determining unit selects a wireless device having the maximum reception level of the response signal, and performs the wireless communication with the selected wireless device. The wireless device according to claim 11, wherein it is determined whether or not to perform the operation. The request transmission means transmits the communication request signal designating a broadcast address as a destination address,
The determination unit selects the other wireless device that has transmitted the reception state information having the lowest reception level of the detection antenna when the response reception unit receives the response signal from a plurality of the other wireless devices. The wireless device according to claim 11, wherein it is determined whether to perform the wireless communication with the selected wireless device. The antenna device is
With the main plate,
The communication antenna disposed at a position away from the ground plane by m × λ / 2−λ / 4 (m is an arbitrary integer of 1 or more, λ is a wavelength of an operating frequency);
A metal wall having a height of n × λ / 2 (where n is an arbitrary integer equal to or greater than m), which surrounds the communication antenna and has one end connected to the ground plane.
The wireless device according to any one of claims 11 to 18, wherein a set of the ground plane and the metal wall corresponds to the metal casing in which the one surface is released. A first wireless device having a first antenna device in which a first communication antenna is installed inside a first metal housing whose one surface is open;
A second antenna device having a second communication antenna installed in a second metal casing with one side open, and a detection antenna provided around the second metal casing; A wireless communication method performed by a wireless device,
The first and second wireless devices are close to each other so that the one surface of the first and second metal casings face each other;
The first wireless device transmits a communication request signal from the first communication antenna to the second wireless device;
The second wireless device inspects the reception state of the radio wave at the detection antenna when the communication request signal is received by the second communication antenna, and sends a response signal including the reception state information of the radio wave to the first Transmitted to the first wireless device by two communication antennas,
The first wireless device determines whether to perform wireless communication with the second wireless device based on the reception state information included in the response signal received by the first communication antenna, and performs the communication. When it is decided to perform, the wireless communication is performed with the two wireless devices via the first communication antenna.
A wireless communication method.

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