JP2007053671A - Communication device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication device capable of realizing a high quality and stable data transmission in a system adopting an electric light line as a transmission medium. <P>SOLUTION: A communication device 511 comprises an electric light cable transmitter 501, and an electric light cable receiver 502 for transmitting and receiving data using an electric light line; a radio transmitter 503 and a radio receiver 504 for transmitting and receiving data using radio; and a transmission medium determination portion 505 for controlling the electric light cable transmitter 501, the electric light cable receiver 502, the radio transmitter 503, and the radio receiver 504, and allowing these portions to transmit and receive data, using both of the electric light cable and radio simultaneously as a transmission medium. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a communication device used for power line communication, and more particularly to a communication device capable of improving the reliability and high speed of data transmission.

  Power line communication that can perform data transmission using existing power lines does not require the installation of a new data transmission path. For this reason, power line communication has been attracting attention as a network infrastructure for homes and access systems because it is possible to construct a network at a low cost. However, power lines are not originally laid for communication purposes. Furthermore, the state of the transmission line of the power line greatly fluctuates due to noise generated by the operating state of various home appliances connected to the outlet. Even when the home appliance is not operating, the impedance in the frequency domain used for data transmission may be very low just by connecting the home appliance to a power outlet. In such a case, the data signal is significantly attenuated on the power line. Furthermore, when the relationship between the outlets to which terminals that communicate with each other are connected is a heterogeneous relationship, the transmission path condition on the power line between these terminals is often poor. In such a poor transmission path environment, the transmitted data does not reach the destination terminal. Alternatively, the transmitted data is not normally received even if it reaches the destination terminal. As a result, data errors may frequently occur.

  As described above, there are various obstacles in using an existing power line for data communication. Many common communication terminals include a data retransmission mechanism in a data link layer or the like. When the transmitted data does not reach the destination terminal, or when it is not normally received at the destination terminal, the data is retransmitted. Even when there is a failure as described above, the data may eventually arrive at the destination terminal due to the retransmission of the data, and the data may be normally received at the destination terminal. However, depending on the condition of the transmission path, even if the data is retransmitted many times, it may not be normally received at the destination terminal, and retransmission may be repeated. Such frequent data retransmission causes a significant decrease in transmission efficiency.

  As a technique for solving the above-described problem, a communication apparatus that uses both a wired communication system such as power line communication and a wireless communication system such as a wireless LAN has been proposed (for example, see Patent Document 1).

  The conventional communication device described in Patent Document 1 switches between both communication methods, a wired communication means for performing wired communication using a power line and the like, a wireless communication means for performing wireless communication using a wireless LAN, and the like. Communication method switching means. The conventional communication device is in a case where the communication status in wired communication such as a power line is inferior due to inter-phase communication in power line communication or the influence of connection with home appliances, that is, transmission data does not reach the destination terminal In addition, when the transmission data is not normally received at the destination terminal and the transmission terminal repeatedly retransmits the data, it is determined that the desired transmission rate cannot be achieved by data transmission using wired communication such as a power line. When such a determination is made, the conventional communication terminal switches from the wired communication means to the wireless communication means by the communication method switching means, and performs data communication using wireless.

  On the other hand, when there is a shield between spatially terminals that perform data communication with each other, the conventional communication device has a poor communication status in wireless communication such as a wireless LAN, and is desirable for data transmission by wireless communication. It is determined that the transmission speed cannot be realized. In such a case, the conventional communication terminal switches data from the wireless communication means to the wired communication means by the communication method switching means, and performs data communication by a wired communication method such as a power line.

  FIG. 29 is a flowchart showing an operation flow in a communication method for switching from power line communication to wireless communication. Hereinafter, an operation flow in a communication method for switching from power line communication to wireless communication will be described with reference to FIG.

  First, the transmitting terminal transmits data using a power line as a communication medium (step S901).

  Next, the transmission terminal evaluates data transmission through the power line when a predetermined fixed period has arrived (step S902). Specifically, for example, the transmission terminal transmits a known signal to the destination terminal at regular intervals. The destination terminal uses the known signal to evaluate the transmission path condition between the transmission terminal and the terminal that is the destination terminal. Then, the destination terminal notifies the transmission terminal of the evaluation result of the transmission path condition. The transmission terminal is notified of the evaluation result from the destination terminal, thereby grasping the transmission path condition on the power line between the transmission terminal and the destination terminal.

  Next, the transmission terminal actually realizes by counting the number of retransmissions and determining how much data the terminal has successfully transmitted using the power line at what time. The transmission rate is calculated, and it is determined whether or not the desired data transmission is realized (step S903).

  If the transmission line condition on the power line is good and the desired data transmission can be realized, the transmitting terminal returns to the operation of step S901 and continues the data communication on the power line.

  On the other hand, due to circumstances such as home appliances connected to an outlet being operated, the transmission path condition becomes poor.For example, when the number of retransmissions of the transmission terminal exceeds a predetermined number or when the transmission path evaluation is performed, the destination is When the parameter indicating the reception status notified from the terminal does not satisfy the predetermined value, or when the actual transmission rate is lower than the desired transmission rate, the transmitting terminal does not transmit the desired data. It is determined that it is possible, and the process proceeds to step S904.

  In step S904, the transmission terminal changes the communication mode such as the modulation scheme and the modulation multi-level, and enhances the noise resistance of the data instead of reducing the amount of data transmitted per fixed time. As a result, although the amount of data that can be transmitted per fixed time is reduced compared to before the communication mode is changed, the probability of data error on the receiving terminal side due to noise or the like is reduced. In this way, by preventing frequent data retransmission, the amount of data normally received on the receiving side per fixed time increases, and a desired transmission rate can be realized even in poor transmission path conditions.

  After step S904, the transmitting terminal evaluates data transmission as described in step S902, and determines whether or not desired data transmission is realized (step S905). When the desired data transmission is realized, the transmitting terminal returns to the operation of step S901 and continues the power line communication in the communication mode.

  On the other hand, due to noise from home appliances, the influence of transmission path fluctuations is large, and even after changing the communication mode such as modulation method and modulation multi-value, the transmission terminal repeats retransmission, etc. If the transmission rate is not realized, the transmitting terminal proceeds to the operation of step S906.

  In step S906, the transmission terminal switches to data transmission using radio, which is one communication medium. Thereafter, the transmitting terminal transmits data by wireless communication (step S907), and completes the data communication (step S908).

Thus, when the communication status of the communication medium being used is poor, data communication is performed using the other communication medium, thereby avoiding the influence of the poor communication status and reducing the transmission efficiency. Can be reduced.
JP 2002-319947 A

  However, as described above, power line communication uses a power line that is not laid for communication purposes as a network infrastructure. Furthermore, in power line communication, the transmission path status varies depending on the relationship between outlets, such as when the relationship between outlets to which communication terminals communicating with each other are connected is in a different phase or in the same phase. Moreover, since the topology of the network changes each time the electrical appliance is plugged in or unplugged, the transmission path status of the power line changes. Further, in general, various home appliances such as a refrigerator, a microwave oven, and an air conditioner are connected to an outlet in a home. Therefore, regardless of whether or not these home appliances use a power line as a communication medium of a data communication network, data transmission using the power line is affected by noise generated by those home appliances. In addition, since existing shortwave broadcasting and amateur radio use a part of the frequency band used by the power line communication system, there is a concern about interference with these other systems in the power line communication. When receiving interference from these other systems, the signals of the other systems and the power line communication signal are mixed, and data transmission in the power line communication is greatly affected. Thus, since there are a wide variety of environments surrounding power line communication, the transmission path over which data communication is performed varies very complexly in terms of frequency and time.

  On the other hand, in wireless communication, if there is a shield such as a wall or ceiling between communication terminals that communicate with each other, the radio wave may be attenuated by the shield and the radio wave may not reach the destination terminal. . Even if the radio wave reaches the destination terminal, if the radio wave is attenuated by the shielding object, the destination terminal cannot receive data normally. Also, various noises and interference sources exist in wireless communication. For example, wireless communication using a 2.4 GHz band such as a wireless LAN is affected by artificial noise leaked from household appliances such as a microwave oven. In addition, the wireless communication interferes with a signal of another communication system that uses the same frequency band, such as a Bluetooth (registered trademark) system.

  Furthermore, power line communication and wireless communication use different communication media and frequency bands. Furthermore, the factors that affect the transmission path conditions in data communication in each method are also different. Therefore, there is no dependency on fluctuations in the transmission line status of power line communication and wireless communication.

  As described above, the transmission path conditions in power line communication and wireless communication fluctuate very complicatedly in terms of frequency and time. In addition, there is no dependency on each transmission path condition. Therefore, the transmission path condition in either one of the communication media is not always good.

  In other words, as in the case of conventional communication devices, when the transmission path status of one of the power lines and radios fluctuates, the desired data transmission is always realized even if the other communication method is switched. It is not always possible. Therefore, as with conventional communication devices, switching between the power line communication method and the wireless communication method according to the status of each transmission line, and the method of performing data transmission using only one of the communication methods, is always high quality and stable. It is difficult to realize data transmission.

  Therefore, an object of the present invention is to provide a communication device that can realize high-quality and stable data transmission in a system using a power line as a communication medium.

  In order to solve the above problems, the present invention has the following features. The present invention is a communication device capable of communicating with other communication devices using a power line and / or radio as a communication medium, a power line transmission / reception unit for transmitting / receiving data using the power line, Communication medium determination that can transmit and receive data by using both the power line and the radio simultaneously as a communication medium by controlling the radio transmission and reception unit for transmitting and receiving data, and the power line transmission and reception unit and the radio transmission and reception unit A part.

  According to the present invention, data is transmitted using both the power line and the radio at the same time, so even if the communication quality of one of the communication media is degraded, the data is sent to the destination communication device. Increases the probability of delivery. Therefore, high quality and stable data transmission can be realized in a system using a power line as a communication medium.

  Preferably, the communication medium determining unit may transmit the data using both the power line and the wireless communication medium at the same time when communication quality of a predetermined level or more is required for the data to be transmitted.

  Thus, for data that requires high quality transmission, the data is transmitted using both communication media simultaneously.

  Preferably, the communication medium determination unit may transmit the data using one of the power line and the wireless communication medium when the communication quality higher than a predetermined level is not required for the data to be transmitted.

  As a result, for data for which high-quality transmission is not required, data is transmitted using either one of the communication media, so that communication resources can be used effectively.

  Preferably, when communication using one communication medium is not normally performed, the communication medium determining unit may transmit data using the other communication medium.

  As a result, the communication medium on which communication is normally performed is used, so that the probability of normal communication can be improved.

  Preferably, when communication using the other communication medium is not normally performed, the communication medium determination unit may transmit data using both the power line and the wireless communication medium at the same time.

  This improves the probability that the data normally reaches the destination communication device.

  Preferably, the communication medium determination unit recognizes the quality of the transmission path between other communication devices as destinations, and based on the recognized quality of the transmission path, both the power line and the radio are used simultaneously. In addition, it may be determined which communication medium is used to transmit the first and second data to be transmitted.

  This improves the probability that two different pieces of data are normally transmitted to the destination communication device.

  Preferably, the communication medium determination unit transmits data having a higher priority among the first and second data using a communication medium having a better transmission path quality, and has a lower priority. Data may be transmitted using a communication medium having a poor transmission path quality.

  As a result, a communication medium having a good quality is assigned to data having a high priority, so that a high-quality and stable communication is realized.

  Preferably, the information processing apparatus further includes an identification information correspondence storage unit for storing data transmitted from another communication device and identification information related to the data, and the communication device to which the data transmitted from the other communication device is a destination normally If not received, the communication medium determination unit may cause the wireless transmission / reception unit or the power line transmission / reception unit to retransmit the data stored in the identification information correspondence storage unit to the destination communication device.

  As a result, the probability that the data normally reaches the destination communication device is improved.

  Preferably, the communication medium determination unit may delete the data and the identification information stored in the identification information correspondence storage unit when receiving an acknowledgment signal from the destination communication device.

  Thereby, useless data and identification information are deleted, so that the storage area in the communication device can be effectively used.

  Preferably, when the communication medium determination unit does not receive a response signal from the destination communication device even after a predetermined time-out period has elapsed, the communication medium determination unit stores the data stored in the identification information correspondence storage unit as the destination It is good to make it retransmit to a wireless transmission / reception part or a power line transmission / reception part.

  As a result, the communication medium is inferior, and even if the response cannot be transmitted even by the destination communication device, data is retransmitted toward the destination communication device, and improvement in communication quality can be expected.

  Preferably, when the communication medium determination unit can normally transmit the data stored in the identification information correspondence storage unit to the destination communication device, the communication medium determination unit acts as a proxy for the communication device of the data transmission source. A proxy retransmission completion signal indicating that retransmission has been completed may be transmitted.

  As a result, the transmission source communication apparatus can recognize that it is not necessary to retransmit the data because the proxy retransmission is normally performed, and the transmission source communication apparatus can reduce processing and traffic. it can.

  Preferably, when the proxy retransmission completion signal is received, the communication medium determination unit determines that it is not necessary to perform proxy retransmission if the proxy retransmitted data is stored in the identification information correspondence storage unit, The data may be deleted.

  As a result, in another communication apparatus that can perform proxy retransmission, it is possible to prevent unnecessary proxy retransmission, thereby reducing the processing burden on the other terminal and reducing traffic.

  Preferably, the communication quality between the communication device that transmitted the proxy retransmission completion signal and the destination communication device, the communication quality between the own device and the destination communication device, and the own device and the proxy retransmission completion signal Based on the communication quality with the transmitted communication device, further comprising a communication route determination unit for determining a communication route from the own device to the destination communication device, by the communication device that has transmitted the proxy retransmission completion signal, The communication quality between the communication apparatus that has transmitted the proxy retransmission completion signal and the destination communication apparatus may be notified.

  As a result, data is transmitted using a communication path with good communication quality, and a high-quality and stable system can be provided.

  Preferably, the communication medium determining unit may store the data and the identification information in the identification information correspondence storage unit when the communication quality between the own device and the destination communication device is equal to or higher than a predetermined quality.

  As a result, the communication quality with the destination communication device is poor, so that even if proxy retransmission is wasted, data is not stored. Therefore, it is possible to improve communication quality and reduce the processing load on the communication device.

  According to the present invention, it is possible to improve the speed and reliability of data transmission by performing data transmission using a plurality of communication media simultaneously. In addition, even when the transmission path conditions in both communication media between the transmission source communication device and the destination communication device are poor, terminals other than the transmission terminal can retransmit data instead of the transmission terminal. It is possible to prevent the transmission terminal from repeating retransmission and to prevent wasteful use of bandwidth. Further, by receiving a proxy retransmission completion signal and obtaining communication status information between the destination communication device added to the proxy retransmission completion signal and the communication device that performed proxy retransmission, a destination that efficiently uses both media Since the communication path to the communication device can be determined, more efficient data transmission can be performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the embodiment of the present invention, a power line and radio are used as an example of a plurality of communication media used for data communication.

(First embodiment)
In the first embodiment, data transmission is performed using both the power line and the wireless communication medium at the same time, thereby reducing the probability of data retransmission of the transmitting terminal and improving the reliability and high speed of data transmission. A communication device that can be used will be described.

  FIG. 1 is a block diagram showing a functional configuration of a communication apparatus according to the first embodiment of the present invention. In FIG. 1, a communication device 511 includes an Ethernet (registered trademark) transmission / reception unit 500, a power line transmission unit 501, a power line reception unit 502, a wireless transmission unit 503, a wireless reception unit 504, and a communication medium determination unit 505. With. The power line transmission unit 501 and the power line reception unit 502 are collectively referred to as a power line transmission / reception unit. The wireless transmission unit 503 and the wireless reception unit 504 are collectively referred to as a wireless transmission / reception unit.

  The Ethernet transmitting / receiving unit 500 performs control for transmitting / receiving data using an Ethernet cable. The power line transmission unit 501 performs control for transmitting data using the power line. The power line receiving unit 502 performs control for receiving data via the power line. The wireless transmission unit 503 performs control for transmitting data using wireless. The wireless reception unit 504 performs control for receiving data via wireless. The communication medium determination unit 505 determines a communication medium to be used for data transmission based on one or more parameters among transmission performance, data type, data amount, and the like required for transmission data. The communication medium determining unit 505 transmits / receives data using the determined communication medium, the Ethernet (registered trademark) transmission / reception unit 500, the power line transmission unit 501, the power line reception unit 502, the wireless transmission unit 503, and the wireless reception. The unit 504 is controlled.

  FIG. 2 is a diagram illustrating an example of a configuration of a communication network to which the communication apparatus illustrated in FIG. 1 is applied. In FIG. 2, the communication network includes communication devices 201 and 202, communication devices 203 and 204, and communication devices 205 and 206. The communication devices 201, 202, 205, and 206 transmit and receive data using only an Ethernet cable as a communication medium. The communication devices 203 and 204 have the configuration shown in FIG. 1, and transmit and receive data using power lines, radio, and Ethernet cables as communication media.

  Each communication device has identification information on each network of power line communication, wireless communication, and Ethernet communication. FIG. 3 is a diagram illustrating an example of identification information. As shown in FIG. 3, for example, for the communication device 203, the identification information on the power line communication network is C1, the identification information on the wireless communication network is C2, and the identification information on the Ethernet communication network is Suppose that it is C3. Further, since the communication device 201 uses only the Ethernet cable as the communication medium, it has only the identification information A3 on the Ethernet communication network. The identification information is, for example, a MAC address.

  In FIG. 2, a solid line arrow indicates a communication path of a power line, a broken line arrow indicates a wireless communication path, and a double line arrow indicates a path of Ethernet communication.

  Here, an Ethernet communication path from the communication apparatus 201 to the communication apparatus 203 is defined as a path 211, an Ethernet communication path from the communication apparatus 202 to the communication apparatus 203 is defined as a path 212, and wireless communication from the communication apparatus 203 to the communication apparatus 204 is performed. The communication path is the path 214, the communication path by the power line from the communication apparatus 203 to the communication apparatus 204 is the path 213, the communication path by Ethernet from the communication apparatus 204 to the communication apparatus 205 is the path 215, and the communication apparatus 204 to the communication apparatus A communication path by Ethernet to 206 is defined as a path 216.

  Here, the communication device 201 sets a route from the communication device 201 to the communication device 206, via the route 211, through at least one of the route 213 and the route 214, and then through the route 216. To do.

  Further, it is assumed that the communication device 202 sets a route through the route 215 after passing through the route 212 and at least one of the route 213 and the route 214 as the route from the communication device 202 to the communication device 205. . Although communication paths other than the above should actually exist, communication paths other than the above are omitted here for simplicity.

  First, consider a case where data is transmitted from the communication device 201 to the communication device 206 in the network shown in FIG. As a route from the communication device 201 to the communication device 206 which is the final destination communication device, a route using the route 211 is first set. Therefore, the communication apparatus 201 transmits data to the communication apparatus 203 via the path 211.

  FIG. 4 is a diagram illustrating a format of data transmitted from the communication apparatus 201 when the communication apparatus 201 transmits data to the communication apparatus 203 via the path 211. In the format example shown in FIG. 4, prior to the data storage field 1004, a field 1001 for storing identification information in Ethernet communication of the final destination communication device of the data, and identification information in Ethernet communication of the transmission source communication device are stored. A field 1002 for storing and a field 1003 for storing identification information for identifying the type and priority of the data are added. In the example shown in FIG. 4, F3 is stored in the field 1001, and A3 is stored in the field 1002.

  The communication device 203 that has received the data shown in FIG. 4 recognizes that the final destination is the communication device 206. As a route to the communication device 206, a route via the route 216 is set via at least one of the route 213 and the route 214. Therefore, the communication device 203 transfers data to the communication device 204.

  When transferring the data to the communication device 204, the communication device 203 uses at least one of a power line and a wireless communication medium according to the flowchart shown below.

  FIG. 5 is a flowchart showing the operation of the communication apparatus according to the first embodiment of the present invention. Hereinafter, the operation of the communication apparatus 203 will be described with reference to FIG.

  First, the communication medium determination unit 505 (hereinafter simply referred to as the communication medium determination unit 505 in the description of FIG. 5) of the communication device 203 that has received the data addressed to its own device identifies the type of data added to the data. The type of data is recognized with reference to the identification information for doing this (step S101). Next, the communication medium determination unit 505 determines whether or not the recognized data type requires high communication quality that is greater than or equal to a predetermined value (step S102). Note that the communication medium determination unit 505 may determine whether the data requires high communication quality with reference to the priority of the data added to the data. Specifically, the communication medium determination unit 505 registers in advance in the table whether or not high communication quality is required according to the type (or priority) of the data, and refers to the table. The determination in step S102 may be performed, and when the data type (or priority) is represented by a certain parameter, the determination may be performed in step S102 by comparing the parameter with a predetermined value. .

  In step S102, when the type of data requires high communication quality, the communication medium determining unit 505 transmits the data to the communication apparatus 204 simultaneously using both the power line and the wireless medium (step S102). S103). Data that requires high communication quality includes control signals. On the other hand, if the data type does not require high communication quality, the communication medium determination unit 505 proceeds to the operation of step S104.

  In step S <b> 104, the communication medium determination unit 505 transfers data to the communication device 204 using either the power line or the wireless communication medium. Here, in step S104, a power line is selected as the communication medium.

  The communication medium determining unit 505 determines whether or not the transmitted data has been normally received on the receiving side based on whether or not an acknowledgment signal has been received (step S105).

  If the data is received normally, the communication medium determination unit 505 causes the power line transmission unit 501 to complete the data transmission (step S106).

  On the other hand, when the data is not normally received, the communication medium determination unit 505 determines whether or not the number of retransmissions exceeds a predetermined value (step S107). If the number of retransmissions does not exceed the predetermined value, the communication medium determination unit 505 retransmits the data using the same communication medium (that is, the power line) as the communication medium selected in step S104 (step S108), and step S105. Return to the operation. Note that, for example, in a situation where the communication device 203 transfers data to the communication device 204 using only the power line, the data transmitted when the outlet of the household electrical appliance is connected or disconnected at the outlet to which the communication device 204 is connected. An error occurs and data is not received normally. If it is determined in step S107 that the number of retransmissions exceeds a predetermined value, the communication medium determination unit 505 proceeds to the operation in step S109.

  In step S109, the communication medium determination unit 505 controls the wireless transmission unit 503 so as to retransmit data using another communication medium (that is, wireless) different from the communication medium selected in step S104. At this time, when the communication device 203 has data to be transferred to the communication device 204 in addition to the data to be retransmitted, the retransmission data is transmitted using radio, and at the same time, the other data is transmitted using the power line. 204.

  After step S109, the communication medium determination unit 505 determines whether or not the transmitted data has been normally received on the receiving side based on whether or not an acknowledgment signal has been received (step S110). When the data is normally received, the communication medium determination unit 505 proceeds to the operation of step S106 and causes the wireless transmission unit 103 to complete the data transmission. On the other hand, when the data is not normally received, the communication medium determination unit 505 determines whether or not the number of retransmissions exceeds a predetermined value (step S111). If the number of retransmissions does not exceed the predetermined value, the communication medium determination unit 505 causes the wireless transmission unit 503 to retransmit the data using the same communication medium (that is, wireless) as the communication medium used in step S109. Control (step S112) and return to the operation of step S110. On the other hand, when the number of retransmissions exceeds a predetermined value, the communication medium determining unit 505 transmits data simultaneously using both communication media (that is, the power line and the radio) (step S113).

  As in step S113, by retransmitting data using both the power line and the wireless medium at the same time, retransmission data is transmitted by the destination communication device 204 as compared with the case where data is retransmitted using only one communication medium. Probability of normal reception increases.

  As described above, according to the first embodiment, when data to be transmitted requires high quality, or the transmission path conditions in both the power line and the wireless medium are not good, data transmission by either one of the communication media In this case, if the data to be transmitted is greatly delayed and the required data transmission is impossible, the data using both media at the same time instead of either the power line or the radio is used. Will be sent. As a result, the probability that data arrives at the destination communication apparatus and is normally received is improved, and as a result, transmission speed and reliability can be improved.

  In the first embodiment, whether or not the data requires high communication quality is determined based on the identification information indicating the type and priority of the data added in the data. High communication quality using parameters such as port number of upper layer protocol, type of upper layer protocol, presence / absence of retransmission, required transmission rate, allowable delay time, etc., or a combination of these It may be determined whether or not the data is required.

  Note that the communication device on the receiving side that is the destination communication device can also be the transmission source, and therefore includes the functional blocks shown in FIG. Since the power line receiving unit and the wireless receiving unit can always receive the transmitted data, when the communication device functions as the receiving side, the communication medium determining unit transmits and receives the power line according to the communication medium to be used. And the wireless transmitter / receiver need not be controlled.

(Second Embodiment)
In 2nd Embodiment, since the structure of a communication apparatus is the same as that of 1st Embodiment, FIG. 1 is used. In addition, FIG. 2 is used as an example of the network configuration, which is the same as that of the first embodiment. In the second embodiment, a description will be given of how the communication medium determination unit 505 of the communication apparatus determines a communication medium to be used when there is a request for transmission (transfer) of a plurality of data.

  FIG. 6 is a flowchart showing the operation of the communication apparatus according to the second embodiment when a plurality of data transmission (transfer) requests are met. Here, in FIG. 2, stream data used for HD-TV transmission or the like is transmitted from the communication device 201 to the communication device 206, and the required transmission speed is lower than the stream data from the communication device 202 to the communication device 205 and the allowable delay is large. The operation of the communication apparatus according to the second embodiment when a plurality of data transmission (transfer) requests are met will be described by exemplifying the case of transmitting data for file transfer or the like.

  The communication device 203 receives the stream data transmitted from the communication device 201 to the communication device 203 via the path 211, and receives the data transmitted from the communication device 202 to the communication device 203 via the path 212. If received, the operation proceeds to step S201.

  In step S201, the communication medium determination unit 505 of the communication device 203 (hereinafter simply referred to as the communication medium determination unit 505 in the description of FIG. 6) identifies information that identifies the type of data added to each received data. And information identifying the priority of data such as a priority value.

  Next, the communication medium determination unit 505 compares the identification information (step S202). In the above example, the communication medium determination unit 505 determines that the stream data from the communication device 201 has a higher priority than the data from the communication device 202.

  Next, the communication medium determining unit 505 performs transmission path evaluation in both the power line and the wireless medium, and the transmission path status (transmission path quality) in both media between the own communication apparatus 203 and the destination communication apparatus 204. (Step S203).

  Next, it is assumed that the communication medium determining unit 505 transmits data having a higher priority using a communication medium having a better transmission path condition and transmitting data having a lower priority using a communication medium having a lower transmission path condition. Then, it is determined which medium is used to transfer each data (step S204). For example, when there is no shielding object between the communication device 203 and the communication device 204, the wireless transmission path condition is good. When the relationship between the outlets to which the communication device 203 and the communication device 204 are connected is in a different phase, the transmission line status of the power line is not good compared to the wireless transmission status. In such a case, the communication medium determination unit 505 determines to transfer the stream data from the communication device 201 having a high priority to the communication device 204 from the communication device 203 using radio having a good transmission path condition. This is because the communication medium determination unit 505 determines that the required transmission speed is higher for the stream data, the allowable delay is smaller, and the priority is higher than the data from the communication device 202. The communication medium determination unit 505 determines that the data received from the other communication apparatus 202 is transferred to the communication apparatus 204 using the power line that is the other communication medium.

  By using a communication medium having a good transmission path condition for transmission of higher priority stream data, data transmission satisfying a high required transmission rate and a low allowable delay can be achieved. In data transmission using the other communication medium, since the transmission path condition is not good, there is a possibility that data will not be correctly received on the receiving side and retransmission will occur. However, the data received from the communication device 202 is lower in required transmission rate than the stream data received from the communication device 201, and a certain delay is allowed. Therefore, although the frequency of retransmission is increased, data transmission can be completed without any problem even when transmission is performed using a communication medium in which the transmission path condition is not good, that is, the required transmission rate and allowable delay can be satisfied.

  As described above, according to the second embodiment, when performing data transmission, the communication medium determination unit 505 determines the type and amount of data to be transmitted, such as a required transmission rate of transmission data, an allowable delay, and retransmission data. Further, both the power line and the wireless communication medium can be used efficiently and simultaneously depending on the transmission path conditions of the power line and the wireless communication medium. Thereby, high-quality data transmission is realized.

  In the second embodiment, the priority is determined based on the identification information indicating the type of data added to the data and the priority value. However, the allowable delay, the required transmission speed, and the data amount of the data are determined. May be added to the data, and the priority may be determined based on the information indicating the allowable delay of the data and the required transmission rate.

(Third embodiment)
In the third embodiment, when there is one communication device that can receive data transmitted from the transmission communication device to the destination communication device, in addition to the transmission communication device and the reception communication device, other than the transmission communication device and the reception communication device. A method for preventing the transmission communication device from repeating data retransmission by retransmitting data to the destination communication device instead of the transmission communication device will be described. In the third embodiment, in a situation before data is transmitted to the destination communication device instead of the transmission communication device, each communication device performs data transmission / reception according to the first or second embodiment. It shall be.

  FIG. 7 is a block diagram illustrating a functional configuration of the communication device 111 according to the third embodiment. In FIG. 7, the communication device 111 includes an Ethernet transmission / reception unit 500, a power line transmission unit 501, a power line reception unit 502, a wireless transmission unit 503, a wireless reception unit 504, a communication medium determination unit 105, and identification information. And a correspondence storage unit 106. In FIG. 7, portions having the same functions as those in the first embodiment are denoted by the same reference numerals, and description thereof is omitted.

  The identification information correspondence storage unit 106 receives the data, the identification information of the data, the identification information of the destination terminal of the data, and the identification information of the transmission source terminal of the data when the destination receives data other than its own device. Remember.

  FIG. 8 is a diagram illustrating an example of a format of information stored in the identification information correspondence storage unit 106 when data other than the own device is received as a destination. As illustrated in FIG. 8, the identification information correspondence storage unit 106 uses, for example, the identification information of the received data as an index, for each identification information of the received data, the corresponding received data, the identification information of the destination terminal of the received data, and A set of identification information of the transmission source terminal of the received data is stored as a list. Note that the format of the information stored in the identification information correspondence storage unit 106 is not limited to the format shown in FIG. 8, and may be a hash structure, for example.

  FIG. 9 is a diagram illustrating an example of a communication network configured by the communication device 111 illustrated in FIG. 7 using a power line, radio, and an Ethernet cable as a communication medium, and a communication device using only an Ethernet cable as the communication medium. is there. In FIG. 9, the communication device 302, the communication device 303, and the communication device 304 have a structure shown in FIG. 7 using power lines, radio, and Ethernet cables as communication media. The communication device 301 and the communication device 305 use only an Ethernet cable as a communication medium. Each communication device has identification information (identifier) on each network of power line communication, wireless communication, and Ethernet communication.

  FIG. 10 is a diagram illustrating an example of a management table of medium-specific communication device identification information stored in the identification information correspondence storage unit 106 of each communication device. In FIG. 10, a set of identification information on the power line network, identification information on the wireless communication network, and identification information on the Ethernet communication network is stored for each communication device.

  Since the communication device 301 uses only Ethernet communication, the identification information on the power line network and the identification information on the wireless communication network are not described for the communication device 301, and only the identification information G3 on the Ethernet communication network is described. Are listed.

  Since the communication device 302 uses all three types of networks, the communication device 302 has identification information H1 on the power line network, identification information H2 on the wireless communication network, and identification information H3 on the Ethernet communication network. Are listed.

  Similarly, since the communication devices 303 and 304 also use all three types of networks, identification information I1, I2, I3 and J1, J2, J3 on each network is described for each of the communication devices 303 and 304. .

  Since the communication device 305 uses only the Ethernet communication network in the same manner as the communication device 301, the identification information on the power line network and the identification information on the wireless communication network are not described for the communication device 305. Only the identification information K3 above is described.

  In FIG. 10, the identification information of all the five communication devices from the communication device 301 to the communication device 305 is described. However, actually, for example, the information held by the communication device 301 is described in a table held by the communication device 301. It does not have to be. Further, in FIG. 10, a format for holding identification information on each network is taken for each communication device, but the format is not necessarily limited to this format.

  In FIG. 9, a solid line indicates a power line, a solid line arrow indicates a communication path on the power line, a dotted line arrow indicates a wireless communication path, and a double line arrow indicates a communication path on Ethernet communication.

  Here, as communication paths between the communication apparatuses, the communication path by Ethernet from the communication apparatus 301 to the communication apparatus 302 is the path 317, the communication path by Ethernet from the communication apparatus 304 to the communication apparatus 305 is the path 318, and from the communication apparatus 302. A communication path by a power line from the communication apparatus 302 to the communication apparatus 303 is a path 313, a communication path by a power line from the communication apparatus 302 to the communication apparatus 303 is a path 313, and a communication path by a power line from the communication apparatus 303 to the communication apparatus 304 is a path 312. Further, a wireless communication route from the communication device 302 to the communication device 304 is a route 314, a wireless communication route from the communication device 302 to the communication device 303 is a route 316, and a wireless communication route from the communication device 303 to the communication device 304 is a route. A route 315 is defined. In the communication device 301, as a communication route from the communication device 301 to the communication device 305, a route that passes through the route 317, passes through at least one of the route 311 and the route 314, and then passes through the route 318 is set. . In the communication device 302, it is assumed that a route that passes through at least one of the route 311 and the route 314 and then passes through the route 318 is set as a communication route from the communication device 302 to the communication device 305. In the communication device 303, it is assumed that a communication route that passes through at least one of the route 312 and the route 315 is set as a communication route from the communication device 303 to the communication device 304.

  Consider a case where data is sent from the communication device 301 to the communication device 305 in the network of FIG. Data transmitted from the communication device 301 and whose destination is the communication device 305 is received by the communication device 302 via the path 317. Since the communication device 302 that has received the data whose destination is the communication device 305 has set a communication route that passes through at least one of the route 311 and the route 314 as the communication route to the communication device 305, the power line The data is transferred to the communication device 304 using at least one of a wireless communication medium. When the communication device 302 transfers the data to the communication device 304 using a power line, the data passes through the path 311. On the other hand, when the data is transferred to the communication device 304 using radio, the data passes through the path 314.

  Here, in the network of FIG. 9, the communication device 302, the communication device 303, and the communication device 304 that use a power line as a communication medium share a communication medium called a power line, and each communication device is physically connected to the power line. Connected.

  Accordingly, the data transmitted from the communication device 302 using the power line and whose destination is the communication device 304 reaches not only the communication device 304 but also the communication device 303 via the power line (path 313). That is, the communication device 303 can receive data transmitted from the communication device 302 to the communication device 304 using the power line. Even when the communication device 302 transfers data to the communication device 304 using wireless communication, if the communication device 303 is within a range where radio waves radiated from the communication device 302 can reach, the communication device 303 passes the route 316. The data addressed to the communication device 304 can be received via.

  FIG. 11 is a flowchart showing the operation of the communication apparatus 111 when data other than the address for the own apparatus is received. Hereinafter, the operation of the communication apparatus 111 when receiving data other than that addressed to the own apparatus will be described with reference to FIG.

  First, when the communication medium determination unit 105 of the communication device 111 (hereinafter, simply referred to as the communication medium determination unit 105 in the description of FIG. 11) receives data other than that addressed to its own device, It is stored in the identification information correspondence storage unit 106 (step S301).

  For example, when the communication apparatus 302 transfers data received from the communication apparatus 301 via the path 311 to the communication apparatus 304 using the power line, the data transferred from the communication apparatus 302 to the communication apparatus 304 via the power line is the path 313. The communication device 303 received via the communication device 304 is the communication device 304, that is, the data identification information (L1) and the data destination communication device even though the data is not addressed to the communication device 304, that is, the device itself. The identification information (J1) on the power line of the communication device 304 and the identification information (H1) on the power line of the communication device 302 that is the transmission source communication device of the data are stored in the identification information correspondence storage unit 106.

  Next, the communication medium determination unit 105 determines whether or not an acknowledgment signal transmitted from the destination communication device has been received (step S302). When the acknowledgment signal is received, the communication medium determining unit 105 deletes each identification information stored in the identification information corresponding device unit 106 (step S303). On the other hand, when the acknowledgment signal is not received, the communication medium determination unit 105 proceeds to the operation of step S304.

  In step S304, the communication medium determination unit 105 determines whether or not a negative acknowledgment signal transmitted from the destination communication device has been received.

  If it is determined in step S304 that a negative response signal has not been received, the communication medium determination unit 105 determines whether or not a timeout time has elapsed (step S305). If the timeout time has not elapsed, the communication medium determination unit 105 returns to the operation of step S302. On the other hand, when the timeout time has elapsed, the communication medium determination unit 105 proceeds to the operation of step S309.

  If it is determined in step S304 that a negative response signal has been received, the communication medium determination unit 105 proceeds to the operation of step S306.

  For example, when the relationship between the outlets to which the communication device 302 and the communication device 304 are connected is different, and the transmission line condition of the power line between the communication device 302 and the communication device 304 is not good, the communication device 304 Suppose that the data transmitted from the communication device 302 to the communication device 304 through the power line cannot be normally received, and a negative response signal is transmitted to the communication device 302 using the communication medium used for receiving the data, that is, the power line. Reply to. As described above, the communication device 303 is physically connected to the communication device 302, the communication device 304, and the power line. Therefore, the communication device 303 can receive the negative acknowledgment signal transmitted from the communication device 304.

  FIG. 12 is a diagram illustrating an example of the format of the negative response signal. In this format example, the negative response signal includes a field 2101 for storing identification information of the destination communication device of the negative response signal, a field 2102 for storing identification information of the transmission source communication device of the negative response signal, and data that has been negatively acknowledged. Field 2103 for storing the identification information. In this example, the field 2101 stores H1, the field 2102 stores J1, and the field 2103 stores L1.

  In step S306, the communication medium determination unit 105 receives the identification information (L1 in the example shown in FIG. 12) of the data that has been negatively acknowledged by the negative response signal and the destination communication device of the negative response signal, that is, the negatively acknowledged data. Identification information (H1 in the example shown in FIG. 12) of the transmitted communication device and the transmission line of the negative response signal, that is, identification information on the power line of the communication device that has made a negative response (in the example shown in FIG. 12) , J1). Then, the communication medium determination unit 105 checks whether the identification information obtained by receiving the negative response signal is stored in the identification information correspondence storage unit 106.

  FIG. 13 is a diagram illustrating an example of information stored in the identification information correspondence storage unit 106. For example, when information as illustrated in FIG. 13 is stored and a negative response signal as illustrated in FIG. 12 is received, the communication device 303 determines that the identification information L1 of the negatively acknowledged data is the received data illustrated in FIG. The identification information H1 on the power line of the destination communication device of the negative response signal is the identification information on the power line of the transmission source communication device of the received data shown in FIG. It is recognized that the identification information J1 is stored as the identification information on the power line of the destination communication device of the received data shown in FIG.

  After step S306, the communication medium determination unit 105 determines whether or not the identification information of the negatively acknowledged data is stored based on the investigation in step S306 (step S307). If not stored, the communication medium determination unit 105 returns to the operation of step S302. On the other hand, if stored, the communication medium determination unit 105 proceeds to the operation of step S308.

  In step S308, the communication medium determination unit 105 determines that the stored data has not been received normally, and proceeds to the operation of step S309.

  In step S309, the communication medium determining unit 105 transmits the power line so that the stored data is retransmitted to the destination communication device of the data using at least one of the power line and the wireless communication medium. The unit 501 and / or the wireless transmission unit 503 are controlled (step S309).

  Next, the communication medium determination unit 105 determines whether or not the reception response signal from the communication device that is the destination of the retransmitted data is an affirmative response (step S310). For example, when data retransmitted from the communication device 303 using at least one of a power line and a wireless communication medium is normally received by the communication device 304, the communication device 304 sends the retransmission to the communication device 303. An acknowledgment signal is returned using the communication medium used for data reception. For example, when the communication apparatus 303 retransmits the data to the communication apparatus 304 using radio, the communication apparatus 304 returns an acknowledgment signal using radio.

  FIG. 14 is a diagram illustrating an example of a format of an acknowledgment signal indicating that the retransmitted data has been normally received. In the format example shown in FIG. 14, the acknowledgment signal includes a field 2201 for storing identification information of the destination communication device of the acknowledgment signal, a field 2202 for storing identification information of the transmission source communication device of the acknowledgment signal, and an acknowledgment. And a field 2203 for storing identification information of the recorded data. In this example, the field 2201 stores identification information I2 on the wireless communication network of the communication device 303 that is the destination communication device of the acknowledgment signal, and the field 2202 is the communication that is the communication device that is the transmission source of the acknowledgment signal. The identification information J2 on the wireless communication network of the device 304 is stored, and the field 2203 stores the identification information L1 of the acknowledged data.

  If it is determined in step S310 that the reception response signal is not an affirmative response signal, the communication medium determination unit 105 returns to the operation of step S309. On the other hand, if it is determined that the reception response signal is an affirmative response signal, the communication medium determination unit 105 recognizes that the data retransmitted by the own communication device has been normally received by the destination communication device, and in step S311 Proceed to operation.

  In step S311, the communication medium determination unit 105 searches for and recognizes the original transmission source communication device of the acknowledged data based on the identification information stored in the identification information correspondence storage unit 106. For example, in the example shown in FIG. 14, the communication medium determination unit 105 searches whether the identification information L1 of the acknowledged data is stored in the identification information correspondence storage unit 106, and if it is stored, the communication information determination unit 105 stores the identification information L1 in the identification information L1. The identification information of the corresponding transmission source communication device is obtained.

  Next, the communication medium determination unit 105 retransmits the data with respect to the original transmission source communication device instead of the original transmission source communication device, and the retransmission data is normal in the destination communication device. The proxy retransmission completion signal for notifying that it has been received is transmitted (step S312), and the process ends.

  For example, the communication device 303 recognizes that the identification information L1 of the acknowledged data is stored as shown in FIG. 13, and further, the data transmission source communication device (transfer source communication) having the identification information L1. It is recognized that the identification information of (device) is H1 and the identification information of the transfer destination communication device is J1 (step S311). Thereby, the communication apparatus 303 transmits a proxy retransmission completion signal to the communication apparatus 302 (step S312).

  FIG. 15 is a diagram illustrating an example of a format of a proxy retransmission completion signal. In this format example, prior to the field 1305 for storing the identification information of the data for which the proxy retransmission has been completed, the field 1301 for storing the identification information of the destination communication device of the proxy retransmission completion signal, the source communication device of the transmission source of the proxy retransmission completion signal A field 1302 for storing the identification information, a field 1303 for storing the identification information of the destination communication apparatus for the data retransmitted by proxy, and a field 1304 for storing the identification information of the original transmission source communication apparatus for the data retransmitted by proxy are added. ing.

  In the example shown in FIG. 15, the field 1305 stores identification information L1 of data for which proxy retransmission has been completed, and the field 1301 stores on the power line communication network of the communication device 302 that is the destination communication device for the proxy retransmission completion signal. Is stored in field 1302, and identification information I1 on the power line communication network of communication device 303, which is the transmission source communication device of the proxy retransmission completion signal, is stored in field 1302, and proxy retransmission is completed in field 1303. The identification information J1 on the power line communication network of the communication device 304 that is the destination communication device of the received data is stored, and the field 1304 includes the light of the communication device 302 that is the original transmission source communication device of the data for which proxy retransmission has been completed. The identification information H1 on the line communication network is stored.

  The communication device 302 that has received the proxy retransmission completion signal recognizes that the data transmitted to the destination communication device 304 and has been negatively acknowledged is proxy retransmitted by the communication device 303 and that the data has been normally received by the communication device 304. . As a result, the communication apparatus 302 determines that it is not necessary to retransmit the data, and does not retransmit the data to the communication apparatus 304.

  Note that the communication medium determination unit 105 may set a timeout time when storing the identification information of the received data in the identification information correspondence storage unit 106. FIG. 16 is a diagram illustrating an example of information stored in the identification information correspondence storage unit 106 when the timeout information is set and the identification information is stored.

  For example, as shown in FIG. 16, the communication device 303 receives data from the communication device 302 to the communication device 304, and the identification information correspondence storage unit 106 stores the data, the identification information L1 of the data, When storing the identification information J1 on the power line of the communication device 304 as the destination communication device and the identification information H1 on the power line of the communication device 302 as the transmission source communication device, a timeout time (X1) is set together. The communication medium determination unit 105 of the communication device 303 stores the identification information in the identification information correspondence storage unit 106, and then transmits the data from the destination communication device of the data during the set timeout period X1. When an acknowledgment signal or negative acknowledgment signal for the data to the original communication apparatus is not received (in the case of “Yes” in step S305 in FIG. 11), the data is retransmitted (step S309 in FIG. 11). .

  As a result, the data transmitted from the communication device 302 to the communication device 304 is not normally received by the communication device 304, and the data (signal) itself does not reach the communication device 304. Even when neither an acknowledgment signal nor a negative response signal is transmitted, the communication apparatus 303 determines that the data needs to be retransmitted, and retransmits the data that has not arrived to the communication apparatus 304 on behalf of the communication apparatus 302. can do. Then, when the data retransmitted by proxy by the communication device 303 is normally received by the communication device 304 and the communication device 303 receives an acknowledgment signal for the proxy retransmission data from the communication device 304, the communication device 303 Then, a proxy retransmission completion signal is transmitted to the communication apparatus 302.

  As described above, according to the third embodiment, the communication device stores data other than that addressed to itself, and retransmits the data to the destination communication device of the data instead of the transmission source communication device of the data. can do. Accordingly, it is possible to prevent the retransmission of data by the transmission source communication device when the transmission path condition between the transmission source communication device and the destination communication device of the data is inferior, and the destination communication device. It is possible to improve the probability that data will arrive normally.

  When receiving data other than that addressed to the own device, the communication device determines the state of the transmission path between the data and the destination communication device, and does not store the data and its identification information depending on the state of the transmission path. You may do it. FIG. 17 is a flowchart showing the operation of the communication apparatus when the data and its identification information are not stored depending on the transmission path condition. Hereinafter, the operation of the communication apparatus when not storing the data and the identification information thereof will be described with reference to FIG.

  First, the communication medium determination unit 105 of the communication device recognizes the destination communication device of the data when receiving data other than that addressed to the own device (step S401). Next, a parameter representing a transmission path condition between the own device and the destination communication device is referred to (step S402). Next, it is determined whether or not the parameter satisfies a predetermined value, that is, whether or not the communication quality between the own device and the destination communication device is equal to or higher than the predetermined quality (step S403).

  For example, the received CNIR at the communication device 304 in each medium between the communication device 303 and the communication device 304 is used as a parameter representing the transmission path status. At this time, if the received CNIR is larger than the predetermined value, the communication medium determining unit 105 of the communication device 303 determines that the parameter satisfies the predetermined value.

  If it is determined in step S403 that the parameter satisfies the predetermined value, the communication medium determination unit 105 of the communication apparatus stores the received data and its identification information in the identification information correspondence storage unit 106 (step S404). On the other hand, if it is not determined that the predetermined parameter value is satisfied, the communication medium determination unit 105 of the communication apparatus does not store the received data and its identification information in the identification information correspondence storage unit 106 (step S405). In the case of step S405, even if the communication medium determination unit 105 of the communication device receives a negative response signal for the data transmitted from the destination communication device of the data, the communication medium determination unit 105 uses the data instead of the transmission source communication device. Do not resend.

  As described above, in a situation where the transmission path condition between the communication device that is going to perform proxy retransmission and the destination communication device is not good, and there is a high probability that the destination communication device will not receive normally even if proxy retransmission is performed. Prevents retransmission of data that has a high probability of being not normally received by the destination communication device. As a result, it is possible to prevent unnecessary traffic from increasing on the network.

(Fourth embodiment)
In the third embodiment, when there is one communication device to be retransmitted instead of the transmission source communication device, the communication device retransmits data to the destination communication device instead of the transmission source communication device. Thus, the method for preventing repeated data retransmission of the transmission source communication apparatus has been described. In the fourth embodiment, when there are two or more communication devices to be retransmitted instead of the source communication device, if one communication device performs proxy retransmission and proxy retransmission is successful, A method for preventing proxy retransmission by the communication apparatus will be described. In the fourth embodiment, in a situation before data is transmitted to the destination communication device instead of the transmission communication device, each communication device performs data transmission / reception according to the first or second embodiment. It shall be.

  Since the functional configuration of the communication device in the fourth embodiment is the same as that in the third embodiment, FIG. 7 is used.

  18 is a diagram illustrating an example of a communication network including the communication device illustrated in FIG. 7 using a power line, radio, and an Ethernet cable as communication media, and the communication device using only an Ethernet cable as the communication medium. . In FIG. 18, the communication network includes communication devices 402, 403, 404, and 406 that perform communication using power lines, radio, and Ethernet cables as communication media, and communication devices 401 and 405 that use only Ethernet cables as communication media. And is composed of.

  Each communication device has identification information on each network of power line communication, wireless communication, and Ethernet communication. FIG. 19 is a diagram illustrating an example of identification information assigned to each communication device. For example, it is assumed that the identification information on the power line communication network of the communication device 406 is M1, the identification information on the wireless communication network is M2, and the identification information on the Ethernet communication network is M3.

  In FIG. 18, a solid line indicates a power line, a solid line arrow indicates a communication path by a power line, a dotted line arrow indicates a wireless communication path, and a double arrow indicates a communication path by Ethernet communication ing. Here, as communication paths between the communication apparatuses, the communication path by Ethernet from the communication apparatus 401 to the communication apparatus 402 is a path 417, the communication path by Ethernet from the communication apparatus 404 to the communication apparatus 405 is a path 418, and from the communication apparatus 402. A communication path by a power line from the communication apparatus 402 to the communication apparatus 403 is a path 413. A communication path by a power line from the communication apparatus 403 to the communication apparatus 404 is a path 412. Further, the wireless communication path from the communication device 402 to the communication device 404 is a route 414, the wireless communication route from the communication device 402 to the communication device 403 is a route 416, and the wireless communication route from the communication device 403 to the communication device 404 is a route. Route 415, communication path from the communication device 402 to the communication device 406 via a power line , A wireless communication route from the communication device 402 to the communication device 406, a wireless communication route from the communication device 406 to the communication device 404 by a power line 422, and a wireless communication route from the communication device 406 to the communication device 404. A communication path is defined as a path 421. By using this, in the communication device 401, a route via the route 418 is set as the communication route from the communication device 401 to the communication device 405 via the route 417 and at least one of the route 411 and the route 414. Has been. In the communication device 403, a communication route passing through at least one of the route 412 and the route 415 is set as a communication route from the communication device 403 to the communication device 404. In the communication device 406, it is assumed that a communication route passing through at least one of the route 421 and the route 422 is set as a communication route from the communication device 406 to the communication device 404.

  Hereinafter, the operation of the communication apparatus according to the fourth embodiment will be described. In FIG. 18, the case where data transmission is performed from the communication apparatus 401 to the communication apparatus 405 as in the third embodiment is illustrated as appropriate. The operation will be described.

  FIG. 20 is a flowchart showing the operation of the communication apparatus according to the fourth embodiment when data other than the address for the own apparatus is received.

  When the communication device 402 transmits data transmitted from the communication device 401 to the communication device 404 using a power line, the data transmitted from the communication device 402 is received by the communication device 404 via the path 411. The communication device 403, the communication device 406, and the communication device 402 share a communication medium called a power line. Accordingly, data transferred from the communication device 402 to the communication device 404 via the power line reaches the communication device 403 via the path 413 and also reaches the communication device 406 via the path 420.

  As described above, the communication medium determination unit 105 of the communication device that has received data other than the one addressed to the own device stores the received data and each identification information in the identification information correspondence storage unit 106 (step S501). Here, the communication device 403 and the communication device 406 transmit the data and the data, even though the destination of the data transferred from the communication device 402 to the communication device 404 using the power line is not addressed to the own communication device. Identification information on the power line communication network of the destination communication device of the data, and identification information on the power line communication network of the transmission source communication device of the data are stored in the identification information correspondence storage unit 106.

  Then, in the same manner as in the third embodiment (steps S302 to S308 in FIG. 11), the communication medium determination unit 105 of the communication device (403, 406) that has received data other than the device addressed from the communication device 404 communicates. When a negative response signal for the data is received to the device 402, it is determined that the data stored in the identification information correspondence storage unit 106 has not been normally received by the destination communication device 404 of the data, and the data is It tries to retransmit to the destination communication device 404 instead of the communication device 402. In the following, among the communication devices 403 and 406 that receive the negative acknowledgment signal from the communication device 404 and perform proxy retransmission to the communication device 404, the communication device 403 performs the communication device 406 in the operation of step S309 in FIG. Consider a case in which the transmission right is obtained earlier and proxy retransmission is performed to the communication device 404.

  The communication apparatus 403 that has obtained the transmission right for proxy retransmission receives the negative acknowledgment signal (step S304 in FIG. 11), and retransmits the negatively acknowledged data to the communication apparatus 404 instead of the communication apparatus 402 (step S308 in FIG. 11). ). Similarly to the third embodiment, when the communication device 403 receives an acknowledgment signal from the communication device 404 for the retransmission data (step S310), the communication device that is the original transmission source of the retransmission data for which the response has been affirmed A proxy retransmission completion signal indicating that the own communication device 403 has completed the retransmission of the data instead of the communication device 402 is transmitted to 402 using the power line (step S312). FIG. 21 is a diagram illustrating an example of the format of a proxy retransmission completion signal. This proxy retransmission completion signal transmitted from the communication device 403 to the communication device 402 reaches not only the communication device 402 that is the destination communication device of the proxy retransmission completion signal but also the communication device 406 via the power line.

  FIG. 20 shows the operation of the communication apparatus that receives the proxy retransmission completion signal. The communication medium determination unit 105 of the communication apparatus that has received the proxy retransmission completion signal without performing the proxy retransmission (step S502) checks whether the data for which the proxy retransmission has been completed is stored in the identification information correspondence storage unit 106 ( Step S503).

  Here, the communication device 406 that has received the proxy retransmission completion signal shown in FIG. 17 from the communication device 403 to the communication device 402 has received the identification transmitted from the communication device whose identification information is H1 to the communication device whose identification information is J1. It is recognized that the data having the information N1 is proxy retransmitted by the communication device that is the transmission source communication device of this proxy retransmission completion signal and the identification information is I1, and is normally received by the destination communication device of the data. Then, the communication device 406 checks whether or not N1 that is identification information of data for which proxy retransmission has been completed is stored in the identification information correspondence storage unit 106. FIG. 22 is a diagram illustrating an example of information stored in the identification information correspondence storage unit 106 of the communication device 403. As illustrated in FIG. 22, the communication device 403 recognizes that the identification information correspondence storage unit 106 stores identification information N1 and data having the identification information N1.

  Returning to FIG. 20, after step S503, the communication medium determination unit 105 determines whether data for which proxy retransmission has been completed is stored (step S504). When the data for which the proxy retransmission has been completed is not stored, the communication medium determination unit 105 returns to the operation of step S502. On the other hand, when data for which proxy retransmission has been completed is stored, the communication medium determination unit 105 proceeds to the operation of step S505.

  In step S505, the communication medium determination unit 105 determines that the proxy retransmission of the data stored in the identification information correspondence storage unit 106 has been completed. Next, the communication medium determination unit 105 determines that it is not necessary to perform proxy retransmission of the stored data (step S506), and deletes the stored data and each corresponding identification information (step S507). The process is terminated. Here, the communication device 406 receives from the identification information correspondence storage unit 106 data having identification information N1, identification information N1 of the data, identification information J1 of the destination communication device of the data, and source communication of the data The device identification information H1 is deleted so that the proxy retransmission of the data is not performed.

  As described above, according to the fourth embodiment, the communication apparatus receives the proxy retransmission completion signal, stores the identification information identical to the identification information of the data for which the proxy retransmission has been completed, in the identification information correspondence storage unit 106. The identification information, the data having the identification information, the identification information of the destination terminal of the data, and the identification information of the transmission source terminal of the data are deleted from the identification information correspondence storage unit 106, and the data Do not perform proxy resend of. As a result, retransmission of data that has already been normally received by the destination communication apparatus can be prevented, and unnecessary traffic on the network can be prevented from increasing.

(Fifth embodiment)
In the fourth embodiment, when there are two or more communication devices to be retransmitted instead of the transmission communication device, one communication device performs proxy retransmission, and when the proxy retransmission is successful, A method for preventing proxy retransmission of a communication device has been described. In the fifth embodiment, when the proxy retransmission is successful, the transmission source communication device uses the proxy retransmission completion signal that the communication device that performed the proxy retransmission transmits to the original transmission source communication device of the retransmission data. A method for determining a communication path with higher transmission efficiency to the destination communication apparatus will be described. In the fifth embodiment, in a situation before data is transmitted to the destination communication device instead of the transmission communication device, each communication device performs data transmission / reception according to the first or second embodiment. It shall be.

  FIG. 23 is a block diagram illustrating a functional configuration of a communication device 611 according to the fifth embodiment. In FIG. 23, parts having the same functions as those in the first and third embodiments are denoted by the same reference numerals and description thereof is omitted. 23, the communication device 611 includes an Ethernet transmission / reception unit 500, a power line transmission unit 501, a power line reception unit 502, a wireless transmission unit 503, a wireless reception unit 504, and an identification information correspondence storage unit 106. A medium determination unit 605 and a communication path determination unit 607 are provided.

  The communication path determination unit 607 transmits the transmission path status between the communication apparatus that has performed proxy retransmission and the destination communication apparatus, the transmission path status between the local apparatus and the communication apparatus that has performed proxy retransmission, the own apparatus, and the destination. Based on the state of the transmission path with the communication apparatus, a communication path to the destination communication apparatus that enables more efficient data transmission is determined.

  In the fifth embodiment, for example, the communication devices 402, 403, 404, and 406 constituting the communication network shown in FIG. 18 are the communication devices shown in FIG. 23 using the power line, the radio, and the Ethernet cable as communication media. Assume that the communication devices 401 and 406 are communication devices that use only an Ethernet cable as a communication medium, as in the fourth embodiment. Further, as in the fourth embodiment, each communication device has, for example, the identification information shown in FIG. Furthermore, the communication devices 402, 403, 404, and 406 shown in FIG. 18 represent the communication status in each communication medium between the own communication device and all communication devices connected to the own communication device by a power line or wirelessly. It shall have parameters.

  FIG. 24 is a diagram illustrating an example of a parameter representing a communication status of the communication device. As shown in FIG. 24, for example, the communication device 402 includes a parameter (O1 and P1) indicating a communication status of each communication medium with the communication device 403 and a parameter (O1 and P1) indicating a communication status of each communication medium with the communication device 404. Q1 and R1) and parameters (S1 and T1) representing the communication status of each communication medium with the communication device 406.

  In FIG. 18, when data transmission is performed from the communication device 401 to the communication device 405, a change in the communication path of data from the communication device 402 to the communication device 404 when data is transferred from the communication device 402 to the communication device 404 is considered. .

  First, the communication apparatus 402 transfers the data transmitted from the communication apparatus 401 to the communication apparatus 404 using a power line, wireless, or both media. When the relationship between the outlets to which the communication device 402 and the communication device 404 are connected is in a different phase, or when a home appliance is connected to one of the outlets, a power line between the communication device 402 and the communication device 404 The transmission path condition is not good. In addition, when there is a shielding object between the communication device 402 and the communication device 404, the wireless transmission path condition between the communication device 402 and the communication device 404 is not good. In such a case, if the data transmitted from the communication device 402 is not normally received by the communication device 404, as described in the fourth embodiment, the communication device 403 other than the transmission source communication device 402 of the data. Alternatively, the communication device 406 retransmits data that was not normally received by the communication device 404 instead of the communication device 402.

  When the communication apparatus 403 performs proxy retransmission and the data retransmitted by proxy by the communication apparatus 403 is normally received by the communication apparatus 404, an acknowledgment signal for the data retransmitted by the communication apparatus 403 is transmitted from the communication apparatus 404 to the communication apparatus. It is returned to 403. When the communication device 403 receives this acknowledgment signal, the communication device 404 uses the at least one of the power line and the wireless communication medium to indicate that the retransmitted data on behalf of the communication device 402 has been normally received by the communication device 404. 402 is notified. FIG. 25 is a diagram illustrating an example of the format of a proxy retransmission completion signal in the fifth embodiment. For example, as shown in FIG. 25, the communication device 403 includes a parameter (hereinafter referred to as a communication status parameter) indicating communication quality on the power line between itself and the destination communication device 404 in the proxy retransmission completion signal to the communication device 402. And a wireless communication status parameter between the device itself and the destination communication device 404 are added. Note that the communication device 402 recognizes the communication status parameter in each communication medium based on the transmission speed with the destination communication device 404 or the like.

  FIG. 26 is a flowchart showing the operation of the transmission source communication apparatus that has received the proxy retransmission completion signal. Hereinafter, the operation of the transmission source communication apparatus that has received the proxy retransmission completion signal will be described with reference to FIG.

  The communication path determination unit 607 of the transmission source communication device that has received the proxy retransmission completion signal refers to the proxy retransmission completion signal and determines the communication status parameter of each communication medium between the destination communication device and the communication device that has performed proxy retransmission. Obtain (step S601).

  Next, the communication path determination unit 607 refers to the communication status parameter of each communication medium between the communication device that has undergone proxy retransmission and its own device, and the communication status of each communication medium acquired in step S601 with reference to the proxy retransmission completion signal. Based on the parameters, among the communication paths to the destination communication apparatus, a communication path that relays data to be transmitted to the proxy communication apparatus that has been resent by proxy and transmits the data to the destination communication apparatus, and a communication path that directly transmits to the destination communication apparatus Parameters such as the transmission speed to be realized are calculated and compared (step S602). In the example illustrated in FIG. 18, the communication apparatus 402 transmits data to the communication apparatus 403 that has performed proxy retransmission via the path 413, and the communication apparatus 403 relays the data to the communication apparatus 404 via the path 415. A first communication path for transmission, and a second communication path for transmitting data to the communication apparatus 403 via the path 416, and for the communication apparatus 403 to relay the data and transmit to the communication apparatus 404 via the path 412. Calculating a parameter representing transmission efficiency such as a transmission speed realized in each communication path for the current communication path (that is, a path for transmitting data directly to at least one of the path 411 and the path 414). ,Compare.

  Next, the communication path determination unit 607 determines the communication path with the highest transmission efficiency among the calculated parameters as the communication path to the destination communication apparatus (step S603). Thereafter, the communication medium determination unit 605 determines a communication medium to be used so that data is transmitted using the communication path determined by the communication path determination unit 607, and the power line transmission unit 501 and the power line reception unit. 502, the wireless transmission unit 503, and the wireless reception unit 504 are controlled.

  For example, when the communication status parameter is a carrier-to-interference noise power ratio (CINR), the communication path determination unit 607 determines the CINR value, the modulation multi-value number calculated from the value, the transmission speed, And the parameter is compared for each communication path to the destination communication apparatus, and the communication path having the highest transmission efficiency indicated by the parameter is selected.

  FIG. 27 is a diagram illustrating an example of a communication network using a transmission rate as a communication status parameter in order to compare the transmission efficiency of each communication path to a destination communication device. As described above, as illustrated in FIG. 24, the communication device 402 communicates between the communication status parameter in each communication medium between the communication device 402 and the communication device 404 and each communication between the communication device 402 and the communication device 403. The communication status parameter in the medium and the communication status parameter in each communication medium between the communication device 402 and the communication device 406 are held. Further, the communication device 402 receives the proxy retransmission completion signal transmitted from the communication device 403, whereby communication in each communication medium between the communication device 403 and the communication device 404 added to the proxy retransmission completion signal. Get status parameters. The communication device 402 calculates a transmission rate that can be realized in each communication path based on a communication status parameter in each communication medium. The numerical value on each communication path in FIG. 27 is a transmission rate that can be realized in each path calculated by the communication apparatus 402. The communication device 402 calculates the transmission rate of each communication path from the communication device 402 to the destination communication device 404 based on the calculated numerical value.

  As shown in FIG. 27, the transmission speed of the communication path from the communication apparatus 402 to the communication apparatus 404 via the path 411 using only the power line is 5 Mbps. The transmission speed of the communication path from the communication apparatus 402 to the communication apparatus 404 via the path 414 using only radio is 5 Mbps. The transmission speed of the communication path from the communication apparatus 402 to the communication apparatus 404 via the path 411 and the path 414 using the power line and the radio at the same time is set using only the power line and passing through the path 411 and using only the radio. The total with the route 414, that is, 10 Mbps.

  Consider a communication path that is transmitted from the communication apparatus 402 to the communication apparatus 403 via the path 413 using the power line, and transmitted to the communication apparatus 404 via the path 415 using the wireless communication. The transmission speed realized in the path 413 is 30 Mbps. The transmission speed realized in the path 415 is 25 Mbps. The communication device 402 that transmits via the path 413 and the communication device 403 that transfers data received via the path 413 via the path 415 transmit data using different communication media. In other words, the communication device 403 can receive data transmitted from the communication device 402 at a transmission rate of 30 Mbps, and simultaneously transfer the received data to the communication device 404 at a transmission rate of 25 Mbps using wireless communication. Therefore, in the case of a communication path in which the communication device 402 transmits data to the communication device 403 using a power line, and simultaneously transfers data received by the communication device 403 to the communication device 404 using wireless communication, the communication device 402 transmits the data. The transmission rate at which the data arrives at the destination communication device 404 is the smaller of the transmission rate realized on the route 413 and the transmission rate realized on the route 415, that is, 25 Mbps.

  Similarly, the transmission speed is 5 Mbps in the case of a communication path transmitted from the communication apparatus 402 to the communication apparatus 403 via the path 416 using radio, and transmitted from the communication apparatus 403 to the communication apparatus 404 via the path 412 using the power line. It becomes.

  As described above, the communication path determination unit 607 of the communication apparatus 402 calculates the transmission rate realized by each communication path to the communication apparatus 404. As a result, the communication path determination unit 607 of the communication apparatus 402 uses the communication line from the communication apparatus 402 to the communication apparatus 404 as the communication path from the communication apparatus 402 to the communication apparatus 403 using the power line. Simultaneously with the data transmission, it is determined that the communication path for transferring the data received by the communication apparatus 403 to the communication apparatus 404 by radio is the communication path that can obtain the highest transmission rate (the highest efficiency).

  Here, when the communication apparatus 402 transmits data to the communication apparatus 403 using wireless communication and transfers the data received by the communication apparatus 403 to the communication apparatus 404 using wireless communication, the communication apparatus 402 transmits data to the communication apparatus 403. When the communication medium used for data transmission and the communication medium used by the communication apparatus 403 for data transfer to the communication apparatus 404 are the same, the communication apparatus 402 and the communication apparatus 403 perform data transmission using the same communication medium. Therefore, data transmission from the communication device 402 to the communication device 403 and data transfer from the communication device 403 to the communication device 404 cannot be performed simultaneously. Therefore, the communication path to the destination communication apparatus through two paths using the same communication medium, that is, the communication apparatus 402 transmits data to the communication apparatus 403 using the power line, and the data received by the communication apparatus 403 is transmitted to the power line. And a communication path for transmitting data to the communication apparatus 403 using wireless communication and a communication path for transferring data received by the communication apparatus 403 to the communication apparatus 404 using wireless communication. The communication path determination unit 607 determines that the communication path is inefficient, and does not enter such a communication path candidate that uses such a communication path.

  As described above, when the communication path determination unit 607 determines that the communication path using the path 413 and the path 415 as the communication path from the communication apparatus 402 to the communication apparatus 404 can perform the most efficient transmission, The communication device 402 transmits the data received from the communication device 401 to the communication device 403 via a path 413 using a power line. Then, the communication device 403 relays the received data and transmits it to the communication device 404 via the path 415.

  FIG. 28 is a diagram illustrating an example of a data format when the data received by the communication device 403 is relayed and transmitted to the destination communication device 404. In the data format shown in FIG. 28, prior to the data storage field 705, a field 703 for storing the identification information of the final destination communication device of the data and the identification information of the first transmission source communication device of the data are stored. A field 704, a field 701 for storing identification information of the data transfer destination communication apparatus, and a field 702 for identifying the data transfer source communication apparatus are added. In the example shown in FIG. 28, the field 701 stores identification information I1 on the power line communication network of the communication device 403 that is the data transfer destination communication device. The field 702 stores identification information H1 on the power line communication network of the communication device 402 which is the communication source device of the data. The field 703 stores identification information K3 on the Ethernet communication network of the communication device 405 that is the final destination communication device of the data. The field 704 stores identification information G3 on the Ethernet communication network of the communication device 401 which is the first transmission source communication device of the data.

  The communication device 403 that has received the data from the communication device 402 via the path 413 recognizes the identification information of the final destination communication device 405. Since a communication path that passes through at least one of the path 412 and the path 415 is set as a communication path from the communication apparatus 403 to the communication apparatus 405, the communication apparatus 403 has a path 412 that uses a power line and a path 415 that uses radio. , The other communication medium that is not the communication medium used for receiving the transfer data from the communication device 402, that is, the wireless data is transferred to the communication device 404 via the path 415.

  As described above, according to the fifth embodiment, when a communication apparatus that has performed retransmission on behalf of a transmission source communication apparatus notifies the transmission source communication apparatus of completion of proxy retransmission, between the communication apparatus itself and the destination communication apparatus. The communication status in each communication medium is added to the proxy retransmission completion signal. Thus, the transmission source communication device that has received the proxy retransmission completion signal can acquire the communication status in each communication medium between the communication device that has performed proxy retransmission and the destination communication device, and the acquired communication status and The communication path that enables more efficient data transmission can be selected using the communication status between the own communication device and the proxy retransmission communication device that the own communication device has.

  The communication device of the present invention may be realized by a computer device including a CPU executing a program for realizing the operation described above.

  The functional blocks necessary for realizing the communication device of the present invention may be realized as an LSI that is an integrated circuit. These functional blocks may be made into one chip, or may be made into one chip so as to include a part or all of them. Here, LSI is referred to as an IC, a system LSI, a super LSI, or an ultra LSI depending on the degree of integration. Further, the method of circuit integration is not limited to LSI, and circuit integration may be performed with a dedicated circuit or a general-purpose processor. Also, an FPGA (Field Programmable Gate Array) that can be programmed after manufacturing the LSI, or a reconfigurable processor that can reconfigure the connection and setting of circuit cells inside the LSI may be used. Further, if integrated circuit technology comes out to replace LSI's as a result of the advancement of semiconductor technology or a derivative other technology, it is naturally also possible to integrate function blocks using this technology. There is a possibility of adaptation of biotechnology.

  The communication device according to the present invention has a mechanism that can simultaneously use a plurality of communication media for a communication device that uses a plurality of communication media, a mechanism that performs retransmission on behalf of a transmission source communication device, and more efficient up to the destination communication device. For example, bridge devices that use multiple media such as power line, radio, and coaxial line communication, and communications that use multiple media as well. It is useful for computers with built-in modules, printers, and various network home appliances.

The block diagram which shows the functional structure of the communication apparatus which concerns on the 1st Embodiment of this invention. The figure which shows an example of a structure of the communication network to which the communication apparatus shown in FIG. 1 is applied. The figure which shows an example of identification information The figure which shows the format of the data transmitted from the communication apparatus 201, when the communication apparatus 201 transmits data addressed to the communication apparatus 203 via the path | route 211. The flowchart which shows operation | movement of the communication apparatus which concerns on the 1st Embodiment of this invention. The flowchart which shows operation | movement of the communication apparatus which concerns on 2nd Embodiment when the transmission (transfer) request | requirement of several data meets. The block diagram which shows the functional structure of the communication apparatus 111 in 3rd Embodiment. The figure which shows an example of the format of the information memorize | stored in the identification information corresponding | compatible memory | storage part 106, when a destination receives data other than an own apparatus. The figure which shows an example of the communication network comprised by the communication apparatus 111 shown in FIG. 7 which uses a power line, radio | wireless, and an Ethernet cable as a communication medium, and the communication apparatus which uses only an Ethernet cable as a communication medium. The figure which shows the example of the management table of the communication apparatus identification information classified by medium memorize | stored in the identification information corresponding | compatible memory | storage part 106 of each communication apparatus. Flowchart showing operation of communication device 111 when data other than addressed to own device is received The figure which shows an example of the format of a negative response signal The figure which shows an example of the information memorize | stored in the identification information corresponding | compatible memory | storage part 106 The figure which shows an example of the format of the acknowledgment signal which shows that the retransmitted data was received normally The figure which shows an example of the format of a proxy retransmission completion signal The figure which shows an example of the information stored in the identification information corresponding | compatible memory | storage part 106 when setting timeout time and memorize | stored identification information Flowchart showing the operation of the communication device when not storing the data and its identification information depending on the transmission path condition The figure which shows an example of the communication network comprised by the communication apparatus shown in FIG. 7 which uses a power line, radio | wireless, and an Ethernet cable as a communication medium, and the communication apparatus which uses only an Ethernet cable as a communication medium. The figure which shows an example of the identification information allocated to each communication apparatus The flowchart which shows operation | movement of the communication apparatus which concerns on 4th Embodiment when data other than addressed to an own apparatus is received. The figure which shows an example of the format of a proxy retransmission completion signal The figure which shows an example of the information memorize | stored in the identification information corresponding | compatible memory | storage part 106 of the communication apparatus 403. The block diagram which shows the functional structure of the communication apparatus 611 which concerns on 5th Embodiment. The figure which shows an example of the parameter showing the communication condition which a communication apparatus has The figure which shows an example of the format of the proxy retransmission completion signal in 5th Embodiment The flowchart which shows operation | movement of the transmission source communication apparatus which received the proxy retransmission completion signal The figure which shows an example of the communication network which used the transmission rate as a communication condition parameter in order to compare the transmission efficiency of each communication path to a destination communication apparatus. The figure which shows an example of a data format when relaying the data which the communication apparatus 403 received, and transmitting to the destination communication apparatus 404 Flow chart showing an operation flow in a communication method for switching from power line communication to wireless communication

Explanation of symbols

511 Communication device 500 Ethernet transmission / reception unit 501 Power line transmission unit 502 Power line reception unit 503 Wireless transmission unit 504 Wireless reception units 505, 105, 605 Communication medium determination unit 106 Identification information correspondence storage unit 607 Communication path determination unit

Claims (14)

A communication device capable of communicating with other communication devices using a power line and / or radio as a communication medium,
A power line transmitting and receiving unit for transmitting and receiving data using the power line;
A wireless transceiver for transmitting and receiving data using the wireless;
A communication medium determining unit that controls the power line transmission / reception unit and the wireless transmission / reception unit to simultaneously transmit and receive data using both the power line and the radio as the communication medium; A communication device.   The communication medium determining unit transmits the data using both the power line and the wireless communication medium at the same time when communication quality of a predetermined level or more is required for the data to be transmitted. The communication apparatus according to claim 1.   The communication medium determining unit transmits the data using one of the power line and the wireless communication medium when communication quality of a predetermined level or higher is not required for the data to be transmitted. The communication device according to claim 2.   The communication according to claim 3, wherein the communication medium determining unit transmits the data using the other communication medium when communication using the one communication medium is not normally performed. apparatus.   When the communication using the other communication medium is not normally performed, the communication medium determination unit transmits the data using both the power line and the wireless communication medium at the same time. The communication apparatus according to claim 4.   The communication medium determining unit recognizes the quality of a transmission path with another communication apparatus as a destination, and based on the recognized quality of the transmission path, both the power line and the radio are used simultaneously. The communication apparatus according to claim 1, wherein the communication apparatus determines which communication medium is used to transmit the first and second data to be transmitted.   The communication medium determining unit transmits data having a higher priority among the first and second data using a communication medium having a better transmission path quality, and data having a lower priority. The communication apparatus according to claim 1, wherein a communication medium having a poor transmission path quality is transmitted. An identification information correspondence storage unit for storing data transmitted from another communication device and identification information related to the data;
When the data transmitted from the other communication device is not normally received by the destination communication device, the communication medium determination unit uses the data stored in the identification information correspondence storage unit as the destination communication. The communication apparatus according to claim 1, wherein the wireless transmission / reception unit or the power line transmission / reception unit is retransmitted to the apparatus.   The communication medium determination unit, when receiving an acknowledgment signal from the destination communication device, erases the data and the identification information stored in the identification information correspondence storage unit. Item 9. The communication device according to Item 8.   When the communication medium determining unit does not receive a response signal from the communication device serving as the destination even after a predetermined time-out period has elapsed, the communication medium determining unit uses the data stored in the identification information correspondence storage unit as the destination communication. The communication apparatus according to claim 8, wherein the wireless transmission / reception unit or the power line transmission / reception unit is retransmitted to the apparatus.   If the communication medium determination unit can normally transmit the data stored in the identification information correspondence storage unit to the destination communication device, the communication medium determination unit acts as a proxy for the communication device of the data transmission source. 9. The communication apparatus according to claim 8, wherein a proxy retransmission completion signal indicating that retransmission has been completed is transmitted.   When the proxy retransmission completion signal is received, the communication medium determination unit determines that it is not necessary to perform proxy retransmission if the proxy retransmitted data is stored in the identification information correspondence storage unit, 12. The communication apparatus according to claim 11, wherein the data is erased. Communication quality between the communication apparatus that has transmitted the proxy retransmission completion signal and the destination communication apparatus, communication quality between the own apparatus and the destination communication apparatus, and transmission of the own apparatus and the proxy retransmission completion signal A communication path determination unit for determining a communication path from the own apparatus to the destination communication apparatus based on the communication quality with the communication apparatus performed,
12. The communication quality between the communication apparatus that has transmitted the proxy retransmission completion signal and the destination communication apparatus is notified by the communication apparatus that has transmitted the proxy retransmission completion signal. Communication equipment.   The communication medium determination unit stores the data and the identification information in the identification information correspondence storage unit when communication quality between the own device and a destination communication device is equal to or higher than a predetermined quality. The communication apparatus according to claim 8.

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