JP2014230181A - Communication device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication device capable of preventing in-device interference.SOLUTION: A communication device 1 includes a plurality of communication units 2, 3 and wired interfaces 4, 5 for connecting the communication units 2, 3 via wireline in a communicable manner. The communication units 2, 3 can notify the other communication units 2, 3 of the own communication state via the wired interfaces 4, 5. While one communication unit 2 is receiving data, the other communication unit 3 does not start data transmission.

Description

  The present invention relates to a communication device including a plurality of communication devices.

  Conventionally, a communication device equipped with a plurality of communication devices for reasons such as different communication methods, for example, a wireless repeater including a wireless communication device for a terminal and a wireless communication device for a base station, a wireless local area network ( There is a mobile phone or the like equipped with a wireless communication device for WLAN and a wireless communication device for Bluetooth (registered trademark).

  When each wireless communication device of such a communication device uses wireless communication and uses the same frequency band, while one wireless communication device is receiving data, the other wireless communication device When data transmission is started, in-device interference occurs in which data transmission of the other wireless communication device interferes with data reception of one wireless communication device. Therefore, there is a problem that one wireless communication device cannot receive data continuously.

  In addition, a communication method in which a plurality of wireless communication devices use wireless communication using the same frequency band and each wireless communication performs carrier sense (that is, check the communication status of other wireless communication devices, In the case where each wireless communication device operates independently, when another wireless communication device operates independently, the other wireless device can perform communication with another wireless device. When the communication device starts carrier sense, the one wireless communication device that started carrier sense first starts data transmission earlier than the other wireless communication device that started carrier sense later. Accordingly, there is a problem that a wireless communication apparatus that has started carrier sense cannot start data transmission until the wireless communication apparatus that has started carrier sensing first completes data transmission.

  As a countermeasure for the above problem, conventionally, in a wireless repeater including two types of wireless communication devices, that is, a wireless communication device for a terminal and a wireless communication device for a base station, an interference canceller is used to wrap around the other wireless communication device. A method for avoiding in-device interference by removing signal components is disclosed (for example, see Patent Document 1).

  In addition, when mounting a wireless communication device for WLAN and a wireless communication device for Bluetooth using the same frequency band on the same device, the state of the two wireless communication devices (device state such as operating state, power saving state, etc.) is considered. A method of giving priority to each wireless communication device is disclosed (for example, see Patent Document 2).

JP 2001-186072 A Special table 2012-530472 gazette

  For example, in a communication device equipped with a first communication device and a second communication device using wireless communication, when the second communication device starts data transmission while the first communication device is receiving data, the first communication device The data received up to and the data transmitted from the second communication device are received. At this time, when the signal level in the reception band of the first communication device of the data transmitted from the second communication device is a level that interferes with the reception level of the data that the first communication device has received so far In this case, the first communication device cannot continue to receive the data that has been received. That is, in-device interference occurs. This in-device interference is not limited to the case where the first communication device and the second communication device use the same frequency band, and unnecessary radiation contained in the output signal from the second communication device is caused by the first communication device. This includes cases of interference. In order to avoid in-device interference, it is necessary to provide an interference canceller. However, if an interference canceller is provided, there is a problem that the circuit scale and power consumption increase, leading to an increase in cost.

  In the case where the first communication device and the second communication device use wireless communication, for example, the first communication device is a communication method in which carrier sense is performed, and the second communication device is a communication method in which carrier sense is not accompanied. When the second communication device starts data transmission during the carrier sense of the first communication device, the first communication device receives the data transmitted from the second communication device. At this time, when the signal level in the transmission band of the first communication device of the data transmitted from the second communication device is higher than the carrier sense level of the first communication device, the carrier sense result of the first communication device is There is no channel available, and the first communication device cannot start its own data transmission until the data transmission of the second communication device is completed. That is, there is a restriction on data transmission timing in the first communication device (hereinafter referred to as transmission timing restriction).

  In the case where the first communication device and the second communication device use wireless communication and the first communication device and the second communication device perform the carrier sense, for example, the first communication device is in the carrier sense. When the second communication device starts carrier sense, the carrier sense of the first communication device is completed before the carrier sense of the second communication device is completed, and the first communication device starts data transmission. At this time, when the signal level in the transmission band of the second communication device of the data transmitted from the first communication device is higher than the carrier sense level of the second communication device, the carrier sense result of the second communication device is There is no channel available, and the second communication device cannot start its own data transmission until the data transmission of the first communication device is completed. That is, there is a transmission timing restriction in the second communication device.

  In contrast to the above problem, Patent Document 1 includes the above-described interference canceller in order to avoid in-device interference. Therefore, there is a problem that the circuit scale and power consumption increase, leading to an increase in cost.

  Further, in Patent Document 2, the state as a communication device such as whether the wireless communication device is in an operating state or a power saving state is taken into consideration, and therefore, when two wireless communication devices operate simultaneously, It is possible to prevent the other wireless communication device from starting data transmission while the other wireless communication device is receiving data, or to prevent the other wireless communication device from starting carrier sensing while the other wireless communication device is performing carrier sensing. Have difficulty.

  The present invention has been made to solve these problems, and an object of the present invention is to provide a communication device that can avoid in-device interference.

  In order to solve the above-described problems, a communication device according to the present invention includes a plurality of communication devices and an interface that wire-connects the communication devices so that they can communicate with each other, and each communication device transmits its communication state via the interface. Each of the other communication devices can notify the other communication device, and when one communication device is receiving data, the other communication devices do not start data transmission.

  According to the present invention, it is provided with a plurality of communication devices and an interface for wired connection of the communication devices so that they can communicate with each other, and each communication device can notify each other communication device of its communication state via the interface. In the case where one communication device is receiving data, the other communication devices do not start data transmission, so that it is possible to avoid in-device interference.

It is a block diagram which shows an example of a structure of the communication apparatus by Embodiment 1 of this invention. It is a flowchart which shows an example of operation | movement of the communication apparatus by Embodiment 1 of this invention. It is a flowchart which shows another example of operation | movement of the communication apparatus by Embodiment 1 of this invention. It is a flowchart which shows an example of operation | movement of the communication apparatus by Embodiment 2 of this invention. It is a flowchart which shows another example of operation | movement of the communication apparatus by Embodiment 2 of this invention. It is a flowchart which shows an example of operation | movement of the communication apparatus by Embodiment 3 of this invention.

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

<Embodiment 1>
FIG. 1 is a block diagram showing an example of a configuration of a communication device 1 according to Embodiment 1 of the present invention.

  As illustrated in FIG. 1, the communication device 1 includes a first communication device 2, a second communication device 3, and a wired interface 4 that is wired to be communicable from the first communication device 2 toward the second communication device 3. And a wired interface 5 that is wired to be communicable from the second communication device 3 toward the first communication device 2.

  The first communication device 2 can communicate with the first opposing communication device 6 wirelessly, and the second communication device 3 can communicate with the second opposing communication device 7 wirelessly.

  The first communication device 2 and the second communication device 3 correspond to different systems, respectively. Accordingly, the first communication device 2 and the first counter communication device 6 are communication devices corresponding to the same system, and the second communication device 3 and the second counter communication device 7 are communication devices corresponding to the same system. Here, a different system means each system in which each communication device and a communication device to be externally communicated are connected through different communication paths.

  The first communication device 2 is in one of three states (that is, its own state) in which the first communication device 2 is transmitting data, receiving data, or is not performing data transmission and data reception. The communication state is notified to the second communication device 3 via the wired interface 4 as the communication state of the first communication device 2.

  The second communicator 3 sets one of the three states that are waiting while the second communicator 3 is transmitting data, receiving data, or not performing data transmission and data reception. 3 is notified to the first communication device 2 via the wired interface 5.

  FIG. 2 is a flowchart showing an example of the operation of the communication device 1, and particularly shows the operation of the first communication device 2.

  In FIG. 2, the N communication devices (the first communication device 2 and the second communication device 3) provided in the communication device 1 use a wireless communication system in which no carrier sense is performed, and the first communication device 2. The operation at the time of starting data transmission of the first communication device 2 when there is a communication device whose threshold is smaller than the transmission data signal level of the first communication device in its own reception band among other communication devices ing.

  Note that the threshold value set in each communication device is determined based on, for example, the reception sensitivity of each communication device, that is, the minimum received power for obtaining a required quality (communication quality). It is assumed that the threshold set in each communication device is shared by other communication devices.

  In the following description, a communication device whose threshold is smaller than the transmission data signal level of another k-th communication device (k is an integer not less than 1 and not more than N) within its own reception band is referred to as the coverage of the kth communication device. Interference communication device. The interfered communication device of the k-th communication device is not limited to one, and all communication devices satisfying the above conditions are interfered communication devices.

  In step S11, a request for data transmission to the first opposed communication device 6 is made.

  In step S12, it is determined whether a communication state indicating that data is being received is notified from the interfered communication device. When the communication status indicating that data is being received is notified from the interfered communication device, the processing in step S12 is repeated (that is, waiting until the communication status indicating that data is being received from the interfered communication device is not notified). To do). On the other hand, when the communication state indicating that data is being received is not notified from the interfered communication device, the process proceeds to step S13. Here, which communication device is the interfered communication device is determined based on the transmission data signal level of the first communication device 2 and the threshold value set in the other communication device.

  In step S13, data transmission to the first opposite communication device 6 is started, and the process is terminated.

  As described above, the first communication device 2 transmits data from the first communication device 2 in order to start data transmission after the interfered communication device completes data reception (when the interfered communication device is not receiving data). It can be avoided that the received signal becomes interference at the time of data reception of the interfered communication device.

  FIG. 3 is a flowchart showing another example of the operation of the communication apparatus 1, and particularly shows the operation of the first communication device 2.

  In FIG. 2, whether or not data transmission is possible is determined by checking the data reception state of the interfered communication device. However, since the power consumption during transmission of each communication device is large, the instantaneous maximum power consumption in the entire communication device 1 is reduced. When there is a purpose such as, it is possible to avoid simultaneous transmission of data by a plurality of communication devices by combining the operation shown in FIG. 2 with the operation shown in FIG. The operation shown in FIG. 3 will be described below.

  In step S21, data transmission to the first counter communication device 6 is requested.

  In step S22, it is determined whether or not a communication state indicating that data is being transmitted from another communication device has been notified. When the communication status indicating that data transmission is in progress is notified from another communication device, the process of step S22 is repeated (that is, waiting until the communication status indicating that data transmission is in progress is not notified from another communication device). To do). On the other hand, when the communication state indicating that data transmission is being performed is not notified from another communication device, the process proceeds to step S23.

  In step S23, data transmission to the first opposite communication device 6 is started, and the process is terminated.

  From the above, by combining the operation shown in FIG. 2 and the operation shown in FIG. 3, it is possible to avoid simultaneous transmission of data by a plurality of communication devices, so that the instantaneous maximum power consumption in the entire communication device 1 is reduced. be able to.

  From the above, according to the first embodiment, when the interfered communication device (one communication device) is receiving data, each of the other communication devices does not start data transmission. It can be avoided that the signal transmitted from the device becomes interference when receiving data of the interfered communication device. In addition, when one communication device is transmitting data, the other communication devices do not start data transmission, so that the instantaneous maximum power consumption in the entire communication device can be reduced.

  In FIG. 1, the wired interface 4 and the wired interface 5 are illustrated as separate signal lines, but may be configured with a common wired interface as long as the interfaces can communicate bidirectionally.

  Moreover, although FIG. 1 shows the case where the communication device 1 includes two communication devices (first communication device 2 and second communication device 3), the communication device 1 may include three or more communication devices. In this case, it is assumed that each communication device is wired to be communicable with all other communication devices via a wired interface.

  2 and 3, the first communication device 2 has been described. However, other communication devices (N−1 communication devices) other than the first communication device 2 perform the same operation as in FIGS. Shall.

  In addition, in FIG. 3, the present invention is not limited to the case where all of the communication devices use wireless communication, but can be applied to the case where any of N communication devices performs wired communication with an external communication device. is there.

  In the case where the operation shown in FIG. 2 and the operation shown in FIG. 3 are combined, the processing order of step S12 in FIG. 2 and step S22 in FIG.

<Embodiment 2>
In the second embodiment of the present invention, a case will be described in which any of N communication devices provided in a communication device uses a communication scheme in which carrier sense is performed.

  The configuration of the communication device 1 according to the second embodiment is the same as that shown in FIG.

  In the following description, it is assumed that the first communication device 2 uses a communication method in which carrier sense is performed. That is, the first communication device 2 (carrier sense communication device) performs carrier sense prior to data transmission.

  Referring to FIG. 1, the first communication device 2 is on standby when the first communication device 2 is transmitting data, receiving data, performing carrier sensing, or not performing data transmission, data reception, and carrier sensing. One of the four states is notified as the communication state of the first communication device 2 to the second communication device 3 via the wired interface 4.

  The second communicator 3 sets one of the three states that are waiting while the second communicator 3 is transmitting data, receiving data, or not performing data transmission and data reception. 3 is notified to the first communication device 2 via the wired interface 5.

  FIG. 4 is a flowchart showing an example of the operation of the communication device 1, and particularly shows the operation of the first communication device 2.

  In FIG. 4, the first communication device 2 uses a communication method in which carrier sense is performed, and among the communication devices other than the first communication device 2, the threshold is the transmission of the first communication device within its own reception band. The operation | movement at the time of the data transmission start of the 1st communication apparatus 2 in case there exists a communication apparatus smaller than a data signal level, ie, an interfered communication apparatus, is shown.

  Note that the threshold value set in each communication device is determined based on, for example, the reception sensitivity of each communication device, that is, the minimum received power for obtaining a required quality (communication quality). It is assumed that the threshold set in each communication device is shared by other communication devices.

  In step S31, a request for data transmission to the first opposite communication device 6 is made.

  In step S32, carrier sense is started.

  In step S33, it is determined whether there is a channel available. If there is no available channel, the process proceeds to step S32. On the other hand, if there is a vacant channel, the process proceeds to step S34.

  In step S34, it is determined whether a communication state indicating that data is being received is received from the interfered communication device. When a communication state indicating that data is being received is notified from the interfered communication device, the process proceeds to step S32. On the other hand, when the communication state indicating that data is being received is not notified from the interfered communication device, the process proceeds to step S35.

  In step S35, data transmission to the first opposite communication device 6 is started, and the process is terminated.

  From the above, the first communication device 2 starts data transmission after the carrier sense is performed and after the interfered communication device completes data reception (when the interfered communication device is not receiving data). It can be avoided that the signal transmitted from the first communication device 2 becomes interference at the time of data reception of the interfered communication device.

  As another example, for example, during the carrier sense of the first communication device 2, another communication device, for example, the second communication device 3 starts data transmission, and the first communication device of the data transmitted from the second communication device 3. 2 is higher than the carrier sense level of the first communication device 2, the result of the carrier sense of the first communication device 2 is that there is no channel available, and the first communication device 2 performs the second communication. Until the data transmission of the machine 3 is completed, the data transmission cannot be started.

  In order to solve the above problem, in the second embodiment, other communication devices other than the first communication device 2 check the carrier sense state of the first communication device 2 before starting data transmission, After the first communication device 2 performs carrier sense and starts data transmission, data transmission is started from itself.

  FIG. 5 is a flowchart showing another example of the operation of the communication device 1, and particularly shows the operation of the second communication device 3. In FIG. 5, description will be made assuming that the other communication device other than the first communication device 2 is the second communication device 3.

  In step S41, a request for data transmission to the second opposite communication device 7 is made.

  In step S42, it is determined whether or not a communication state indicating that carrier sense is being performed is notified from the first communication device 2. When the communication state indicating that the carrier sense is being performed is notified from the first communication device 2, the process of step S42 is repeated (that is, the communication state indicating that the carrier sense is being performed is not notified from the first communication device 2). Wait until). On the other hand, when the communication state indicating that the carrier sense is being performed is not notified from the first communication device 2, the process proceeds to step S43.

  In step S43, data transmission to the second opposite communication device 7 is started, and the process ends.

  From the above, according to the second embodiment, a communication device (one communication device) that performs carrier sense determines that carrier sense is performed and data transmission is possible, and then the other communication devices (covered devices). Since the data transmission is started when the interfering communication device is not receiving data, it is possible to avoid that the signal transmitted from the communication device performing carrier sense becomes an interference at the time of data reception of the interfered communication device. . In addition, when a communication device that performs carrier sense is in carrier sense, each other communication device that does not perform carrier sense starts data transmission after the communication device that performs carrier sense completes carrier sense. It is possible to avoid a transmission timing restriction in a communication device that performs sensing.

  In the second embodiment, the first communication device 2 has been described as using a communication method in which carrier sense is performed. However, N−1 communication devices other than the first communication device 2 perform communication in which carrier sense is performed. It is also applicable when using the method.

  Further, although the first communication device 2 has been described with reference to FIG. 4, other communication devices other than the first communication device 2 that do not perform carrier sense may perform the operation illustrated in FIG. 2. You may make it perform the operation | movement which combined the operation | movement shown and the operation | movement shown in FIG.

  In FIG. 5, the case has been described where the first communication device 2 is the only communication device that cannot transmit data when the second communication device 3 starts data transmission. However, the present invention is not limited to this. In addition to the first communication device 2, when there is a communication device that cannot transmit data when the second communication device 3 starts data transmission, the second communication device 3 includes all communication devices that perform carrier sense. Data transmission is started after confirming that carrier sense is not being performed.

<Embodiment 3>
In Embodiment 3 of the present invention, a case will be described in which all communication devices included in a communication device use a communication scheme in which carrier sense is performed. That is, each communication device (carrier sense communication device) performs carrier sense prior to data transmission.

  The configuration of the communication device 1 according to the third embodiment is the same as that shown in FIG.

  Referring to FIG. 1, the first communication device 2 is on standby when the first communication device 2 is transmitting data, receiving data, performing carrier sensing, or not performing data transmission, data reception, and carrier sensing. One of the four states is notified as the communication state of the first communication device 2 to the second communication device 3 via the wired interface 4.

  The second communication device 3 is one of the four states in which the second communication device 3 is in the middle of data transmission, data reception, carrier sense, or standby in which data transmission, data reception, and carrier sense are not performed. This state is notified to the first communication device 2 via the wired interface 5 as the communication state of the second communication device 3.

  The first communication in the case where there is a communication device whose threshold is smaller than the transmission data signal level of the first communication device, that is, the interfered communication device, within the communication band other than the first communication device 2 The operation at the start of data transmission of the machine 2 is the same as the operation shown in FIG. Specifically, after performing carrier sense, the first communication device 2 starts data transmission after the interfered communication device completes data reception (when the interfered communication device is not receiving data). Therefore, it can be avoided that the signal transmitted from the first communication device 2 becomes interference when the interfered communication device receives data. The same applies to communication devices other than the first communication device 2.

  Note that the threshold value set in each communication device is determined based on, for example, the reception sensitivity of each communication device, that is, the minimum received power for obtaining a required quality (communication quality). It is assumed that the threshold set in each communication device is shared by other communication devices.

  As another example, for example, when the first communication device 2 starts carrier sense during the carrier sense of the second communication device 3, the carrier sense of the second communication device 3 is completed during the carrier sense of the first communication device 2. The second communication device 3 starts data transmission. The result of the carrier sense of the first communication device 2 when the signal level of the data transmitted from the second communication device 3 within the reception band of the first communication device 2 is higher than the carrier sense level of the first communication device 2 No channel is available, and the first communication device 2 cannot start its own data transmission until the data transmission of the second communication device 3 is completed.

  In order to solve the above problem, in the third embodiment, the first communication device 2 confirms the carrier sense state of other communication devices other than the first communication device 2 before starting carrier sense, The first communication device 2 and other communication devices start data transmission at the same time.

  FIG. 6 is a flowchart showing an example of the operation of the communication device 1, and particularly shows the operation of the first communication device 2. In FIG. 6, it is assumed that the second communication device 3 is included in communication devices other than the first communication device 2.

  In step S51, a request for data transmission to the first opposed communication device 6 is made.

  In step S <b> 52, it is determined whether a communication state indicating that carrier sense is being performed is notified from a communication device other than the first communication device 2. When the communication state indicating that carrier sense is being performed is not notified from another communication device, the process proceeds to step S53. On the other hand, when a communication state indicating that carrier sense is being performed is notified from another communication device, the process proceeds to step S56.

  In step S53, carrier sense is started.

  In step S54, it is determined whether there is a channel available. If there is no available channel, the process proceeds to step S53. On the other hand, if there is a vacant channel, the process proceeds to step S55.

  In step S55, data transmission to the first opposite communication device 6 is started, and the process is terminated.

  In step S56, the carrier sense is requested to be interrupted with respect to another communication device in the carrier sense.

  In step S57, carrier sense is started so that carrier sense is completed at the same time (at the same timing) as another communication device in which carrier sense is interrupted. That is, the first communication device 2 and the other communication devices each start carrier sense so that carrier sense is completed simultaneously.

  In step S58, it is determined whether there is a channel available. If there is no available channel, the process proceeds to step S57. On the other hand, if there is a vacant channel, the process proceeds to step S59.

  In step S59, data transmission is started at the same time as another communication device whose carrier sense is interrupted by the request in step S56, and the process is terminated.

  From the above, according to the third embodiment, when all communication devices included in the communication device 1 perform carrier sense, at least one other communication is performed when one communication device performs carrier sense. In the case where the machine has already performed carrier sense, after another communication device interrupts carrier sense, one communication device and another communication device simultaneously start carrier sense so that carrier sense is completed. The communication devices (one communication device and another communication device) can start data transmission at the same time, and the transmission timing restriction in each communication device can be avoided. In addition, since one communication device performs carrier sense and determines that data transmission is possible, the other communication device (interfered communication device) starts data transmission when data is not being received. It can be avoided that the signal transmitted from the communication device becomes interference at the time of data reception of the interfered communication device.

  Although the first communication device 2 has been described with reference to FIG. 6, the same operation is performed for other communication devices other than the first communication device 2.

  In the first to third embodiments, it has been described that one communication device 1 includes a plurality of communication devices (for example, the first communication device 2 and the second communication device 3), but is not limited thereto. For example, one communication device may be provided with one communication device, and the number of communication devices provided in the communication device is arbitrary. At this time, it is assumed that each communication device is wired to be communicable with all other communication devices via a wired interface.

  It should be noted that the present invention can be freely combined with each other within the scope of the invention, and each embodiment can be appropriately modified or omitted.

  DESCRIPTION OF SYMBOLS 1 Communication apparatus, 1st communication apparatus, 2nd communication apparatus, 4,5 Wired interface, 6 1st opposing communication apparatus, 7 2nd opposing communication apparatus.

Claims (9)

With multiple communicators,
An interface for connecting each of the communication devices in a communicable manner;
With
Each of the communication devices can notify each other communication device of its communication state via the interface,
The communication apparatus, wherein when one of the communication devices is receiving data, each of the other communication devices does not start data transmission.   The communication apparatus according to claim 1, wherein the communication state includes a state in which the data is being transmitted, the data is being received, or a standby state in which the data transmission and the data reception are not performed.   3. The communication device according to claim 1, wherein, when one of the communication devices is transmitting the data, each of the other communication devices does not start the data transmission. The one communication device is a carrier sense communication device that performs carrier sense prior to the data transmission,
When the carrier sense communication device is in the carrier sense, each of the other communication devices not performing the carrier sense starts the data transmission after the carrier sense communication device completes the carrier sense. The communication device according to claim 1, wherein the communication device is characterized.   The carrier sense communication device, after performing the carrier sense and determining that the data transmission is possible, starts the data transmission when each of the other communication devices is not receiving the data. The communication apparatus according to claim 4.   The carrier sense communication device includes the communication state including the standby state in which the data transmission, the data reception, the carrier sense, or the data transmission, the data reception, and the carrier sense are not performed. 6. The communication apparatus according to claim 4, wherein the communication apparatus notifies the other communication apparatuses. Each of the communication devices is a carrier sense communication device that performs carrier sense prior to the data transmission,
When one carrier sense communication device performs the carrier sense, when at least one other carrier sense communication device has already performed the carrier sense,
After another carrier sense communication device interrupts the carrier sense, one carrier sense communication device and another carrier sense communication device start the carrier sense so that the carrier sense is completed at the same time. The communication device according to claim 1, wherein the communication device is characterized.   The carrier sense communication device includes the communication state including the standby state in which the data transmission, the data reception, the carrier sense, or the data transmission, the data reception, and the carrier sense are not performed. The communication device according to claim 7, wherein the communication is notified to each of the other carrier sense communication devices.   9. The communication device according to claim 1, wherein each of the communication devices corresponds to a different system.

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