JP2007312176A - Power line communication equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide power line communication equipment by which a user easily learns whether or not communication speed and communication quality are secured before starting data communication by the power line communication equipment connected to a power line. <P>SOLUTION: The power line communication equipment sets a setting value by a criterion setting part 101 which sets a criterion via a user interface 100, a comparison criterion setting part 102 which sets a comparison criterion, a judgment/comparison frequency setting part 103 which sets judgment/comparison frequencies or a judgment/comparison period setting part 104 which sets judgment/comparison periods, judges a state of a transmission path based on information in handshake performed prior to communication with a communication partner by a transmission path state judgment part 105, stores its judgment results in a memory part 107, judgment results accumulated in the memory part 107 are compared with one another by a comparison part 106 and its comparison result is displayed by a display part 108 to notify the user of it. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to information on a personal computer or the like in a power line communication (also referred to as “PLC: Power Line Communication”) system in which a home communication network connected to an external trunk Internet communication network via an ADSL or an optical fiber is constituted by a power line. The present invention relates to a power line communication device such as a PLC adapter that enables information on a terminal (hereinafter abbreviated as “PC”) to be exchanged via a power line.

  At present, power line communication devices mainly for home use that are sold and used in the United States and Europe are adapter types (PLC adapters) that can be directly connected to a power outlet installed on the wall as a power line outlet.

  Many of these types of power line communication devices have an Ethernet (registered trademark) connector in addition to a connection terminal to a power line (a plug of a type that is usually plugged into an outlet). A function to display only the communication establishment such as Ethernet establishment / abnormality was provided.

  With regard to communication speed and communication quality, an information terminal such as a personal computer (hereinafter referred to as “PC”) is connected to the power line communication device that is actually connected to the power outlet, and the throughput that operates on the PC is measured. If the application software to be used is not used, the data throughput is good, that is, the communication speed and communication quality cannot be known.

  From the above, in order to select a power outlet with high communication speed and communication quality among many power outlets in the house, first connect the power line communication device to the power outlet, and connect the PC to the Ethernet. After connecting and starting application software for throughput measurement on a PC, a series of operations such as actual communication occurs, and it takes time to determine the power outlet.

  As a technique for improving the communication speed and communication quality in a power line communication system, conventionally, transmission parameters can be transmitted by using transmission parameters corresponding to the transmission path conditions based on the number of times of error detection / correction of data exchanged and the number of retransmissions. A technique for performing power line communication with high efficiency has been proposed (see, for example, Japanese Patent Laid-Open No. 2000-174731: Patent Document 1).

  In addition, as a communication line connecting the data processing terminal and the terminal controller, a power line and a communication line other than the power line are used together, and a line that is preset as to whether to use a power line or a communication line as a transmission medium for each type of transmission data Proposed technology to improve communication efficiency between power line and communication line by providing selection table and line identification means to identify transmission medium according to the type of transmission data based on the line selection table when transmission data occurs (For example, refer to JP 2000-339551 A: Patent Document 2).

However, the ones disclosed in Patent Documents 1 and 2 relate to a technique for examining the transmission characteristics of a line, but regarding a plurality of power outlets installed in parallel on the same line, it is not possible to investigate the throughput of each power outlet. The problem of being unable to do so remains.
JP 2000-147331 A JP 2000-339551 A

  The present invention has been made to solve the above-described conventional problems, and the user can determine whether the communication speed and the communication quality can be ensured before starting the data communication by the power line communication device connected to the power line. It is an object to provide a power line communication device that can be easily known.

  The present invention provides a power line communication device used in a power line communication system that is interposed between an information terminal and a power line and communicates using the power line as a transmission line, and a power supply unit that supplies power to the power line communication device connected to the power line; The power line communication unit that inputs / outputs communication signals to / from the power line used as the transmission line and the information on the state of the transmission line based on the information at the time of handshake prior to communication with the communication partner when the power line communication device is connected to the power line A transmission path status determination section; a memory section that stores the determination result of the transmission path status determination section; a comparison section that compares the determination results stored in the memory section; and a display section that informs a user of the comparison result. Is a power line communication device.

  In the present invention, it is preferable to provide a determination criterion setting unit for the user to set the determination criterion, determination frequency, or determination cycle of the transmission status path determination unit.

  In the present invention, it is preferable to include a comparison reference setting unit for the user to set the comparison reference, comparison frequency, or comparison cycle of the comparison unit that compares the determination results stored in the memory unit.

  In the present invention, it is preferable that the display unit that informs the user of the comparison result has a function of displaying that the transmission path status is being determined or being compared.

  According to the present invention, when the power line communication device is connected to the power line, the state of the transmission path (for example, the function information of the device and the communication method / method information) is performed based on the information at the time of handshaking prior to communication with the communication partner (for example, The communication method, communication speed, etc. that can be used on the transmission line with the paired power line communication device are determined, and based on the determination result, the power outlet of the power line connected by the user ensures the communication speed and communication quality. Whether it is possible to use LED (photoelectric conversion element), LCD (liquid crystal element), etc., and convey it in an easy-to-understand manner.

  Therefore, when the power line communication device is connected to the power line, it becomes possible to quickly identify the optimum power outlet meeting the user's needs, and the transmission path condition after installation can be monitored.

  For example, when a user selects an outlet with a high communication speed and communication quality from many power outlets in the house, the present invention allows the user to grasp the transmission path status simply by connecting the power line communication device to the power outlet. Since the outlet can be selected easily, as in the past, after installing the power line communication device, connect the PC via Ethernet, start the application software for throughput measurement on the PC and actually communicate Since there is no need to perform work, the power outlet can be determined quickly without taking time.

  In addition, by providing each setting unit and allowing the user to arbitrarily set the determination criteria, comparison criteria, determination / comparison period, and cycle, it is possible to set the communication speed and communication quality that meet the user's needs.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a block diagram illustrating an embodiment (also referred to as a PLC adapter) of a power line communication apparatus according to the present invention.

This power line communication apparatus will be described.
As shown in FIG. 1, the power line communication apparatus according to the embodiment is used in a power line communication system that performs communication between PCs or between a PC and the outside (external line 30) via the power line 10. , A comparison interface, a determination / comparison count, a user interface 100 that is an interface for setting a determination / comparison cycle, a determination criterion setting unit 101 that sets a determination criterion, and a comparison criterion setting unit 102 that sets a comparison criterion A determination / comparison number setting unit 103 for setting the number of determinations and comparisons, a determination / comparison period setting unit 104 for setting the determination / comparison period, and a transmission path based on information at the time of handshaking performed prior to communication with the communication partner. A transmission path status determination unit 105 that determines the status of the transmission path, a memory unit 107 that stores a determination result from the transmission path status determination unit 105, and a memory unit 1 Comparing unit 106 compares the the determination result stored in 7, and a comparison result comprises mainly a display unit 108 to inform the user.

  Further, the power line communication apparatus is configured to supply power to the power line communication apparatuses 201, 203, and 205 based on the power received from the power line 10, and to exchange data between the external line 30 and the PCs 202 and 204. 110 includes a PLC communication unit (power line communication unit) 109 that performs PLC communication from the power line 10 through the power line 10.

  In the embodiment, the broadband router 200 and the PCs 202 and 204 are connected to the PLC communication units 109... Of the power line communication devices 201, 203, and 205 through communication lines 20 such as Ethernet cables.

  Further, the signal path of the external line 30 is connected to the PLC communication unit 109 of one power line communication device via a broadband router 200 and a communication line 20 described later.

  In addition, the PLC communication units 109 of the power line communication apparatuses 201, 203, and 205 can perform PLC communication from the power supply unit 110 through the power line 10.

  The determination criterion setting unit 101 sets the data transmission speed (throughput (Mbps: megabit second)) as a determination criterion within a predetermined or arbitrary range.

  The comparison reference setting unit 102 sets the data transmission rate (throughput) when the power line communication device is connected to the outlet at a predetermined time, for example, as a comparison reference at a predetermined time.

  The determination / comparison count setting unit 103 arbitrarily sets the determination result and the number of determinations performed by the transmission path condition determination unit 105 that repeats the comparison result and the number of comparisons performed by the comparison unit 106.

The determination and comparison are performed multiple times for the following reason.
General household power lines are basically connected to other home appliances, and the noise level generated and whether the impedance of the power line itself is temporal in terms of whether the home appliances are operating or not. Changes to. In addition, transmission path conditions change due to external factors such as being adversely affected by noise such as surges. Therefore, if the determination and comparison are performed once when the power line communication device is connected to the outlet, the result may be influenced by some external factor, and an erroneous determination may be made. Therefore, preferably, a series of procedures for determination and comparison is repeated a plurality of times.

  However, if it is repeated many times, the accuracy of the determination result is increased, or time is spent until the establishment of the line, so in the embodiment, it is repeated five times.

  The determination / comparison cycle setting unit 104 determines and compares the connection status because the communication status changes due to the external factors as described above after connection of the outlet and the initially desired communication quality cannot be ensured or the line connection is interrupted. A series of procedures is performed at a predetermined cycle, for example, every hour.

  In the embodiment, the display unit 108 notifies the user of the comparison result by displaying the red LED and the green LED continuously on or blinking. The display unit can arbitrarily install a display device other than the LED. For example, an LCD (liquid crystal) display can be provided, and the history of determinations and comparison results can be displayed on the display screen as before, last time, and so on.

Next, the details of the power line communication system will be described.
FIG. 2 is a configuration diagram of a communication system in which the power line communication devices 201, 203, and 205 according to the embodiment are arranged. The power line communication apparatuses 201, 203, and 205 connect a plurality (or one) of PCs 202 and 204 to the power line, respectively.

  In the power line communication system shown in FIG. 2, a broadband router 200 having an interface for connecting to an external line such as ADSL or optical fiber, and the broadband router 200 is connected by a communication line 20 (20a) such as an Ethernet cable. A power line communication device 201 that converts data transmitted (received) via the line 20 into data for PLC communication and is connected to the power line 10 to transmit (receive) PLC communication data on the power line 10; Data connected to the PCs 202 and 204 via the communication line 20 (20b and 20c) and transmitted (received) via the communication line 20 is converted into data for PLC communication, and connected to the power line 10, and the power line 10 Power line communication devices 203 and 205 for transmitting (receiving) data It is.

  In the power line communication devices 201, 203, and 205, a low-voltage single-phase power line used for, for example, a household lamp line is used as the power line 10, and a two-terminal type (which may have a ground terminal) of the power line 10 provided as appropriate. Connection is made by inserting a 2p plug into the power outlet 40.

  Here, for example, when the PC 204 tries to connect to the Internet via the broadband router 200 via the external line 30 such as ADSL or optical fiber, the Internet connection request of the PC 204 is transmitted in a normal Ethernet frame (communication Via the line 20) to the power line communication device 205.

  In this case, the power line communication apparatus 205 converts the Internet connection request of the PC 204 from the Ethernet frame to the PLC frame, and transmits it to the power line communication apparatus 201 via the power line 10.

The power line communication apparatus 201 converts the Internet connection request of the received PLC frame into an Ethernet frame and transmits it to the broadband router 200.
The broadband router 200 connects to the Internet through the external line 30 in accordance with the received Ethernet frame data.

  FIG. 3 is a flowchart when the user selects the power outlet 40 to which the power line communication device is connected in the power line communication system shown in FIG. Each step is abbreviated as “S...”.

First, the user connects the PLC adapter to an arbitrary power outlet 40 (S301).
The connected power line communication apparatus starts a handshake for establishing communication with the power line communication apparatus (PLC adapter) 201 connected to the already connected broadband router 200 (S302).

Normally, handshaking is performed to exchange information on the functions installed in communication devices, information on methods and protocols that can be used in actual data communication, and data at the time of handshaking as information. Need to be transmitted. Therefore, in data transmission, a modulation scheme with a short frame size and a low symbol rate is used so that no data error or data retransmission occurs. (For example, in the US power line communication standard Homeplug 1.0 (hereinafter referred to as Homeplug 1.0) established by the Homeplug Powerline Alliance, a US powerline communication promotion organization, ROBO (Robust) A low-speed control mode of 3 to 5 Mbps called an OFDM (orthogonal frequency division multiplexing) mode is used.)
The handshaking method is generally a three-way handshake used in TCP / IP communication (Transmission Control Protocol / Internet Protocol) using message data such as a communication request on the transmission side and a request response on the reception side. . Here, there is no regulation of the handshake method itself, but it is assumed that a 3-way handshake is used to simplify the explanation of the embodiment.

In the handshake exchange, first, the transmission side transmits a communication request including its own device capability information (corresponding protocol, communication speed, etc.) to the communication partner.
The communication partner (reception side) receives the transmission request, extracts the device capability information of the transmission side included therein, and this time sends a request response including the device capability information of the communication partner itself to the transmission side.
The transmission side extracts the device capability information of the communication partner from the request response from the communication partner, takes into account the error rate and reception strength in modulation / demodulation in this series of operations, and is the optimum communication method for itself and the communication partner ( For example, in Homeplug 1.0, parameters such as DBPSK (operational phase modulation system) or DQPSK (differential quadrature phase shift keying) are used as a modulation system, and which subcarrier is used. Selection).
The communication partner that received the notification also gives the permission notification if the notified content is acceptable, taking into account the error rate and reception strength in modulation / demodulation on its own terminal side, and if it is not acceptable, the communication failure notification is sent. At the same time, the transmission side is notified of an acceptable communication method. This exchange is performed until each device can accept it.
As described above, the exchanged data (parameters) is a compromise for mutual communication between the devices, that is, this indicates that the communication is suitable between the current transmission path and the device. (For example, in Homeplug 1.0, in the case of an ideal transmission path, DQPSK is used as a modulation method and communication is performed using 84 subcarriers).

Parameters relating to the optimum communication method exchanged by the above-described handshake are extracted (S303).
Before the power line communication devices 201, 203, 205 are connected to the outlet or before the determination and comparison processing, the determination criterion setting unit 101 and the comparison criterion setting unit 102 have default (or user settings) determination criteria for the transmission path condition. The initial value of the comparison reference of the determination result is set and stored in the memory unit 107 (S304, S305).
In the embodiment, the determination criterion is, for example, a throughput of 2 Mbps to 5 Mbps. Further, the comparison reference is set to the content to be compared with the result when connected to the previous outlet. Of course, at least one of the determination criterion and the comparison criterion can be changed from the default initial value according to the setting or various conditions after the operation of the power line communication apparatus is started.

  Here, based on the parameters related to the optimum communication method exchanged by the extracted handshake, the transmission path status determination unit 105 determines the transmission path status using the set determination criterion (S306). The determination is performed according to the contents such as the initial value of the determination criterion setting unit 101.

The determination result is transmitted to the memory unit 107 and the comparison unit 106.
The memory unit 107 stores the determination result, and the comparison unit 106 compares according to the comparison setting content of the comparison reference setting unit 102 (S307), and transmits the comparison result to the display unit 108 (S308).

The display unit 108 notifies the user of the comparison result using an LED, an LCD, or the like.
In this case, if both the determination result and the comparison result are the results of clearing the respective criteria and the transmission path state in which the line can be established (OK), the green LED is lit on the display unit 108 (S308). ).

  On the other hand, if at least one of the determination result and the comparison result is not a satisfactory result (NG) such that the respective criteria cannot be cleared or the channel condition is difficult to establish (NG), the red LED is lit on the display unit 108 (S309).

FIG. 4 is a flowchart when the user sets determination criteria and comparison criteria.
The user connects the power line communication device to an arbitrary power outlet (S401).

  The connected power line communication device starts a handshake for establishing communication with the power line communication device 201 connected to the already connected broadband router 200 (S402).

  Parameters relating to the optimum communication method exchanged by handshaking are extracted (S403). At this time or after this, the user arbitrarily uses the user interface 100 to set the determination criterion, the comparison criterion, the number of determinations / comparisons, and the determination / comparison cycle, the determination criterion setting unit 101, the comparison criterion setting unit 102, the determination / Comparison count setting unit 103 and determination / comparison cycle setting unit 104 can be set (S404). The user interface 100 may be configured such that a switch such as a dip switch is integrally attached to the power line communication device itself, even if it is not a separate body. The user can make settings directly on the power line communication device.

  If the switch described in the determination criteria, for example, the throughput is 2 Mbps or more and 5 Mbps or less is turned ON by any user setting using the user interface 100, the setting content is set in the determination criterion setting unit 101 ( S405). Based on the determination criteria, the transmission path status is determined based on the handshake information (S406). For example, if it is found from the handshake information that communication is performed at a communication speed of 4 Mbps, it is determined that this transmission path can secure the 4 Mbps communication speed, and the user setting conditions are cleared. You can proceed to the step.

  Also, if the switch described with the comparison result as the previous result is turned ON, the comparison reference of the comparison reference setting unit 102 is set to the content to be compared with the result when connected to the previous outlet. (S407). The comparison unit 106 reads the previous result from the memory unit 107, and compares whether or not the throughput is equal or higher (S408). For example, in this case, assuming that the previous determination result is 3 Mbps, 3 Mbps is stored in the memory unit 107, and the comparison unit 106 compares the 3 Mbps with 4 Mbps. Since the result is better than the previous result, the comparison criterion can be cleared and the process can proceed to the next step.

  If the switch with the number of determinations / comparisons set to 5 is turned ON, the determination / comparison number setting unit 103 is set to repeat the determination / comparison sequence five times (S409). For example, if the result of the procedure up to S408 is 4 Mbps for all five times, the process can proceed to the next step.

  Further, the determination / comparison cycle is set to 1 hour in the determination / comparison cycle setting unit 104 (S411), and the determination / comparison is performed five times and every hour with the same determination / comparison standard ( S410, S412). For example, after 1 hour, the above steps up to S409 are performed again. Similarly, if it is 4 Mbps, the condition is satisfied, and the determination result is OK for the user by the display unit using the display means such as LED or LCD. This is displayed to notify (notify). In addition, it can also be notified by voice or vibration.

If the number of determinations / comparisons increases, it takes time until a comparison result is obtained. During this time, the display unit 108 notifies the user that the determination is being performed using the LED and LCD (S413).
For example, a display method such as blinking an LED may be used.

  Regarding the display of the determination / comparison result on the display unit 108, in the case of the above-described content, if the determination criterion satisfies the throughput of 2 Mbps to 5 Mbps, the process proceeds to the comparison process. If not, the comparison process is performed. At that time, the display is not performed and the LED is lit red (S414).

  On the other hand, if the determination criteria are met and the process shifts to comparison processing, the comparison is performed according to the comparison criteria, and compared with the previous result. If the throughput is equal or higher, the LED is lit in green, etc. Display is performed (S415). If it is less than that, a display such as turning on the LED in red is performed as described above.

It is a block diagram explaining the structure of the power line communication apparatus (PLC adapter) which concerns on embodiment of this invention. It is a connection diagram of the power line communication system according to the embodiment. It is a basic flowchart of transmission-path condition determination. It is a transmission-path condition determination flowchart by a user setting.

Explanation of symbols

10 power line 20 communication line 30 external line 40 power outlet 100 user interface 101 determination reference setting unit 102 comparison reference setting unit 103 determination / comparison number setting unit 104 determination / comparison cycle setting unit 105 transmission path state determination unit 106 comparison unit 107 memory unit 108 Display Unit 109 PLC Communication Unit (Power Line Communication Unit)
110 Power supply 200 Broadband router 202,204 PC
201, 203, 205 Power line communication device (PLC adapter)

Claims (4)

In a power line communication device used in a power line communication system that is interposed between an information terminal and a power line and communicates with the power line as a transmission line,
A power supply unit for supplying power to a power line communication device connected to the power line;
A power line communication unit for inputting / outputting communication signals to / from a power line as a transmission path;
A transmission path status determination unit that determines the status of the transmission path based on information at the time of handshaking prior to communication with the communication partner when the power line communication device is connected to the power line;
A memory unit for storing the determination result of the transmission path status determination unit;
A comparison unit for comparing determination results accumulated in the memory unit;
A power line communication apparatus comprising: a display unit that informs a user of a comparison result.   The power line communication apparatus according to claim 1, further comprising a determination criterion setting unit for a user to set a determination criterion, a determination count, or a determination cycle of the transmission path condition determination unit.   2. The power line communication according to claim 1, further comprising a comparison reference setting unit for a user to set a comparison reference, a number of comparisons, or a comparison cycle of the comparison unit that compares the determination results stored in the memory unit. apparatus.   The power line communication apparatus according to claim 1, wherein the display unit that notifies the user of the comparison result has a function of displaying that the transmission path status is being determined or being compared.