JP2006101179A - Status monitoring method of power line communication network - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power line communication network status monitoring method which acquires status information of the network from all a plurality of terminals for a short time for monitoring the network status by acquiring status information of the plurality of terminals from base stations. <P>SOLUTION: The power line communication network status monitoring method connects a base station BS, a plurality of repeaters RPT, and a plurality of terminals RMT connected to the plurality of repeaters RPT, respectively, through power lines used as transmission lines to constitute a power line communication network system. The plurality of repeaters RPT send broadcast information each to the plurality of terminals RPT connected subordinate to the repeaters at fixed intervals, thus storing response information sent from each of the plurality of repeaters against the sent report information each in own repeater, and send the response information from the terminals RMT stored in own repeaters to the base station BS as response information when the broadcast information are sent from the base station BS. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a power line communication (PLC) network state monitoring method, and more particularly, to a power line communication network state monitoring method for monitoring a network state by collecting terminal device state information from a base station. .

  In recent years, home appliances such as various home appliances have a power line communication function in homes, etc., and monitor and control these home appliances from a master unit constituted by a PC, etc. There has been proposed a system that enables access to the above-described master unit via the Internet, and allows monitoring and controlling home devices from the outside. In addition, it enables high-speed signals to be handled by power line communication, and multimedia information such as video information and audio information from ISPs (Internet Service Providers) via public communication networks including the Internet is real-time A system that enables display on a display device has also been proposed.

  In recent years, large-scale power line communication network systems have been introduced for large-scale condominiums and the like. Such a power line communication network system is connected to a media converter, a switch hub, a base station, a plurality of repeaters connected to the base station, and a plurality of repeaters connected to a global network such as the Internet. Generally, a plurality of terminal devices are connected by a power line. When such a system is applied to a large-scale apartment, etc., each of the terminal devices described above is provided in each residence in the apartment, and a plurality of household electrical appliances, PCs, etc. provided in the residence and the base station. Control of communication between the devices, and control of communication between multiple devices provided in the house.

  In the base station configured as described above, the transmission line used for communication with the terminal device is a power line, so the state of the transmission line with the terminal device is monitored and the state is It is necessary to transmit communication signals. For this reason, the base station needs to monitor the state of the network, and the base station transmits a signal for monitoring the state called general broadcast information to all the terminal devices at regular time intervals from all the terminal devices. To collect response information.

  FIG. 5 is a sequence chart for explaining the state monitoring process performed by the base station, and FIG. 6 is a diagram showing the structure of a data packet as response information that each terminal device transmits to the base station in response to a signal for state monitoring. In the following, the state monitoring method according to the prior art will be described with reference to these drawings. FIG. 5 shows a base station (base station BS), a repeater (repeater RPT), and a plurality of terminal devices (remote terminal devices RMT1 to RMTn). There are multiple units. The illustrated terminal device is a terminal device connected to the illustrated repeater at a lower level.

  In FIG. 5, when the base station intends to monitor the state of the transmission path, first, the base station transmits broadcast information to all the repeaters and terminal devices by broadcast (sequence 501). This broadcast information is received by all of the repeater and the terminal device, and each of the repeater and the terminal device detects the state of the transmission path based on the received broadcast information and uses the state as response information. Return to the station (sequence 502 to 50n). The response information can be returned without confirming that each of the repeater and the terminal device has another communication signal on the power line as the transmission path, so that they do not collide with each other.

  In the above, the configuration of the data packet of the response information returned by each of the repeater and the terminal device is the information indicating the 3-bit transmission power level, the packet length of the 4-bit return packet, as shown in FIG. Information, 1-byte packet control information, maximum 3 bytes of communication speed (transmission rate) information, maximum 2047 bytes of data, and error correction information. Note that the response information for the broadcast information does not include data. The base station that has received such response information controls the transmission information to be optimum when transmitting information to the terminal device based on the information indicating the transmission power level and the communication speed information. Is going.

In addition, the prior art which measures the line quality of the power line at the time of performing data transmission using a power line as mentioned above, and ensures transmission quality is described in patent document 1 etc., for example. In addition, as a conventional technique related to a large-scale power line communication network system as described above, for example, a technique described in Patent Document 2 is known.
JP-A-6-291700 Japanese Patent No. 3330329

  In the state monitoring method according to the above-described prior art, it takes a very long time until the base station can receive the response information from all the terminal devices after transmitting the broadcast information. It has a problem that it cannot be performed. That is, in the large-scale power line communication network system described above, 20 to 30 terminal devices are connected to the lower level of one repeater, and several tens of repeaters are connected to one base station. In general, the number of terminal devices may reach several hundred. From the time when the base station transmits broadcast information to the time when response information is received from all terminal devices. It takes 2 to 3 hours.

  The object of the present invention is to solve the above-described problems of the prior art and collect status information from all terminal devices when monitoring the status of the network by collecting status information of a plurality of terminal devices from the base station. An object of the present invention is to provide a state monitoring method for a power line communication network that can be collected in a short time.

  According to the present invention, the object is to provide a power line in a power line communication network system configured by connecting a base station, a plurality of repeaters, and a plurality of terminal devices connected to each of the plurality of repeaters using a power line as a transmission path. In the communication network status monitoring method, each of the plurality of repeaters transmits simultaneous broadcast information to the plurality of terminal devices connected to the lower level of the repeater at a certain period, and On the other hand, response information transmitted from each of the plurality of terminal devices is stored in the own repeater, and when broadcast information is transmitted from the base station, it is stored in the own repeater. This is achieved by transmitting response information from the terminal device as response information to the base station.

  The object is achieved by the fact that the response information from the terminal device is information indicating the state of the transmission path.

  The object is achieved by the fact that the response information from the terminal device is information calculated by the terminal device for transmission power, data length and transmission rate suitable for communication using the transmission path.

  Furthermore, the object is achieved by the base station performing transmission control of information to each of a plurality of terminal devices based on response information from the terminal devices received from the repeater.

  Embodiments of a power line communication network status monitoring method according to the present invention will be described below in detail with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration example of a power line communication network system to which the present invention is applied, and FIG. 2 is a block diagram showing a basic configuration of a repeater and a terminal device shown in FIG. 1 and 2, 11 to 19 are terminal devices (RMT), 21 to 23 are repeaters (RPT), 24 is a base station (BS), 25 is a switch hub (SWHUB), 26 is a media converter, and 27 is A global network, 28 is a power line, 31 is a transmission circuit, 32 is a reception circuit, 33 is a computing unit, and 34 is a memory.

  As shown in FIG. 1, a power line communication network system to which the present invention is applied includes a base station 24, a plurality of repeaters 21 to 23 connected to the base station 24 using a power line 28 as a signal transmission path, Each of the repeaters 21 to 23 includes a plurality of terminal devices 11 to 19 connected to the same power line 28 as described above as signal transmission paths. The base station 24 is connected to a global network 27 such as the Internet via a switch hub 25 and a media converter 26. A communication path connecting the base station 24 to the media converter 26 may be Ethernet (registered trademark), LAN, or the like.

  In the above description, when a PC or the like connected to the terminal devices 11 to 19 communicates with a provider or the like that performs an information service accommodated in the global network 27, the signal from the terminal device is 1 of the repeaters 21 to 23. After being relayed, the power line communication signal from the terminal device is converted into a communication signal that can be transmitted on the global network 27 under the control of the base station 24, via the switch hub 25 and the media converter 26. The communication signal from the provider or the like is received by the base station 24 via the media converter 26 and the switch hub 25, and the communication signal on the global network 27 is controlled by the base station 24. Is converted into a power line communication signal and transmitted to a predetermined terminal device.

  The repeaters 21 to 23 and the terminal devices 11 to 19 include a well-known PLC modem chip and a signal superimposing circuit (including a separation circuit) on the power line, and basically have the same configuration. As shown in FIG. 2, a transmission circuit 31, a reception circuit 32, a calculator 33, and a memory 34 are provided. When the circuit shown in FIG. 2 is a repeater, the repeater receives the power line communication signal on the power line 28 by the receiving circuit 32, amplifies, and then transmits the power line communication signal from the transmission circuit 31 to the power line 28. It is only necessary to perform the operation. The power line communication signal on the power line stores the address of the terminal that is performing communication. Therefore, the repeater transmits / receives the terminal device connected to the lower level of its own repeater using this address. It is sufficient to perform the relay operation only for the power line communication signal being received.

  When the circuit shown in FIG. 2 is a terminal device and a PC or the like is directly connected to the terminal device, the PC or the like is connected to the computing unit 33 via an interface. In this case, the terminal device processes a signal including various information including sound, images, data, and the like from a PC or the like by the arithmetic unit 33 to convert the signal into a power line communication signal, and the power line communication signal is transmitted to the transmission circuit. It is sufficient to transmit from 31 to the power line 28. The power line communication signal transmitted from the terminal device to the power line 28 is transmitted to the global network 27 via the repeaters 21 to 23 and the base station 24. A communication signal from the global network 27 received by the base station 24 is received by a predetermined terminal device via the repeaters 21 to 23 and input to a PC or the like. It is also possible to perform communication between terminal devices. In this case, terminal devices that are subordinate to the same repeater can directly communicate with each other and terminals that are subordinate to different repeaters. The devices can communicate with each other via each repeater.

  Further, in the case where the circuit shown in FIG. 2 is a terminal device, and this terminal device performs monitoring control of home appliances and the like in the house, this terminal device is provided in each of the home appliances in the house. It is possible to control each household electrical appliance by performing communication using a power line as a transmission path with a terminal device having a similar configuration, and monitoring signals from various sensors in the household electrical appliance And can be transmitted to a central monitoring device or the like on the global network 27.

  In the system configured as described above, as in the case of the prior art, the base station needs to monitor the state of the transmission path with the terminal device and transmit a communication signal according to the state. There is. Next, a power line communication network state monitoring method for monitoring the state of the transmission line in the embodiment of the present invention will be described.

  FIG. 3 is a sequence chart for explaining a process in which the base station performs state monitoring in the embodiment of the present invention, and FIG. 4 shows a data packet transmitted to the repeater as response information to the broadcast information for each terminal device for state monitoring. FIG. 1 is a diagram illustrating a configuration, and a state monitoring method according to an embodiment of the present invention will be described below with reference to these drawings. For simplification of explanation, FIG. 3 shows a base station, one repeater, and two terminal devices (RMT1, RMT2). As described above, there are a plurality of devices and a large number of terminal devices.

  First, a sequence for monitoring the state of the power line network will be described with reference to FIG.

(1) The repeater transmits broadcast information to a plurality of terminal devices under the supervision of the own repeater connected to the lower order of the own repeater at a constant cycle. In this case, the broadcast information is also received by the base station, but the base station ignores the broadcast information and does not respond (sequences 301 and 302).

(2) Each terminal device detects the state of the transmission path based on the received broadcast information, and returns the state to the repeater as response information. The repeater receives the response state including the line state information from each terminal device, stores the line state information included in the response information in the memory table in the own repeater, and updates it (sequence 303). -304).

  Although not shown, the processes of sequences 301 to 304 are performed for a plurality of terminal devices that are monitored by a self-relay device in which a plurality of repeaters are independently connected to a lower level of the self-relay device. And update the memory table in the repeater.

(3) The base station transmits the broadcast information to a plurality of repeaters under the supervision of the base station connected to the lower level of the base station at a constant cycle. This broadcast information is also received by the terminal device. However, the terminal device detects that the broadcast information is issued from the base station, and ignores the broadcast information and transmits a response signal. No (sequence 305 to 307).

(4) In the sequence 305, the broadcast information transmitted from the base station is received by each repeater. Then, the repeater that has received the broadcast information from the base station transmits the line state information included in the response information from each terminal device stored in the memory table in the own repeater to the base station. Based on the information received from the relay station, the base station stores and manages information on the line state of all terminal devices managed by the base station in a memory provided therein (sequence 308). .

  In the above description, when a terminal device is newly added to the power line communication network monitored by the repeater, the repeater additionally stores and manages the added terminal device information in the internal memory table. When the terminal device is deleted, the deleted terminal device information is deleted from the internal memory table. And in the above-mentioned sequence, when the broadcast information is received from the base station, information on addition and deletion of those terminal devices is transmitted to the base station. In addition, the repeater transmits information to the base station even when there is a large number of additions and deletions of terminal devices and the table in the memory is significantly changed, even when a general broadcast from the base station is not transmitted. can do.

  Next, the configuration of a data packet that is transmitted as response information to the repeater when each terminal device receives broadcast information for state monitoring will be described with reference to FIG.

  As shown in FIG. 4, the configuration of the data packet of the response information returned by each terminal device is as follows: 2-byte packet control information, transmission power level consisting of a maximum of 3 bytes, packet (data) length, communication Information including speed (transmission rate) and bit error rate, data of maximum 2047 bytes, and error correction information. Note that the response information for the broadcast information does not include data.

  The information including the transmission power level (transmission power), the packet length, the transmission rate, and the bit error rate included in the information composed of a maximum of 3 bytes described above receives the broadcast information transmitted from the repeater by each terminal device. Then, the state of the transmission line is judged from the error state of the received data, and the optimum transmission power, packet length, and transmission rate are calculated. Information on the transmission power, packet length, and transmission rate optimized in this way is stored in a data packet as response information and transmitted to the repeater.

  As described above, when the repeater receives the response information for the broadcast information, the repeater receives the optimized transmission power, data length, and transmission rate information included in the response information for the terminal device. Stored in the memory table. After that, when the repeater receives the broadcast information from the base station, the repeater transmits the above-described optimized transmission power, data length, and transmission rate information for each terminal device stored in the table in the memory. Send to station.

  When the base station receives the information on the optimized transmission power, data length, and transmission rate for each terminal device transmitted from the repeater as response information to the broadcast information, the base station stores the received information in the base station. Store as data in the memory. These pieces of information are information indicating what state each terminal device is in via the transmission line using the power line, and are used by a system administrator or the like.

  That is, the installer or administrator of the power line communication network system to which the present invention is applied can know what the state of the transmission path is by reading and checking the above-mentioned data in the base station. It is possible to improve the portion of the transmission line that is in a bad state.

  According to the embodiments of the present invention described above, a media converter connected to a global network such as the Internet, a switch hub, a base station, a plurality of repeaters connected to the base station, and each of the plurality of repeaters In a large-scale power line communication network system configured by connecting a plurality of terminal devices connected to each other by a power line, broadcast information is sent to the terminal devices monitored by its own repeater at a certain time interval. By transmitting and collecting and holding the state of the terminal device at regular intervals in advance, when the broadcast information is transmitted from the base station, it is supposed to transmit the held information to the base station. The time required for the base station to collect the state of each terminal apparatus can be greatly reduced.

It is a block diagram which shows the structural example of the power line communication network system to which this invention is applied. It is a block diagram which shows the basic composition of the repeater and terminal device shown in FIG. It is a sequence chart explaining the process in which the base station in embodiment of this invention performs state monitoring. It is a figure which shows the structure of the data packet which each terminal device transmits to a repeater as response information with respect to the broadcast information for state monitoring. It is a sequence chart explaining the process in which a base station performs state monitoring. It is a figure which shows the structure of the data packet as response information which each terminal device transmits to a base station with respect to the signal for state monitoring.

Explanation of symbols

11-19 Terminal equipment (RMT)
21-23 Repeater (RPT)
24 Base Station (BS)
25 Switch Hub (SWHUB)
26 Media Converter 27 Global Network 28 Power Line 31 Transmitter Circuit 32 Receiver Circuit 33 Arithmetic Unit 34 Memory

Claims (4)

In a power line communication network state monitoring method in a power line communication network system configured by connecting a power line to a base station, a plurality of repeaters, and a plurality of terminal devices connected to each of the plurality of repeaters,
Each of the plurality of repeaters transmits simultaneous broadcast information to the plurality of terminal devices connected to a lower level of the repeater at a constant period, and the plurality of relay devices Response information transmitted from each is stored in the own repeater, and when broadcast information is transmitted from the base station, the response information from the terminal device stored in the own repeater is A method for monitoring a state of a power line communication network, characterized by transmitting the response information to a base station.   The power line communication network state monitoring method according to claim 1, wherein the response information from the terminal device is information indicating the state of the transmission path.   2. The power line communication network according to claim 1, wherein the response information from the terminal device is information calculated by the terminal device for transmission power, data length, and transmission rate suitable for communication using the transmission path. Status monitoring method.   4. The power line communication according to claim 1, wherein the base station performs transmission control of information for each of a plurality of terminal devices based on response information from the terminal devices received from the repeater. Network status monitoring method.

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