JPS62107541A - Power line carrier communication repeater - Google Patents

Abstract

PURPOSE:To obtain a repeater excellent in workability and flexibility by constituting the repeater with a reception means receiving a pulse, a pulse head detecting means detecting the head of the pulse, a pulse generating means generating the pulse of a prescribed length after the detection of the head of pulse and a transmission means amplifying the generated pulse and sending the result to a power line. CONSTITUTION:A reception means 11 being a component of the repeater receives a pulse of power line carrier communication comprising a high frequency signal sent from a control equipment and the received pulse is fed to the pulse head detection means 12. When the pulse head detection means 12 detects the pulse head, the information is sent to a pulse generating means 13, which generates a pulse of a prescribed width used for the power line carrier communication after the detection of the head of pulse, the pulse is amplified at the transmission means 14 and sent to a power line 10. Thus, in installing the repeater, it has only to be executed by the parallel connection to the power line thereby improving the performance of work.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a power line carrier communication repeater using an indoor commercial power line as a communication transmission path.

Conventional technology A communication system using power lines as a communication transmission path is
1' In order to facilitate the separation of frequency components and signal components, a pulse signal using a carrier wave of a sufficiently higher frequency is superimposed on the 50 Hz or 60 Hz AC voltage of the power line to control indoor electrical equipment. This is what we do. This has the advantage that there is no need for special wiring for control, so the effort and cost associated with installation is low. However, power lines have the disadvantage that the impedance as a communication transmission path changes depending on the electrical equipment connected and the length of the power line, and the signal level also changes, making control impossible in some cases.

Moreover, the frequency and signal strength of the high-frequency signals to be superimposed are limited by legal regulations such as the Radio Law and electrical equipment technical standards. One way to solve the above problem is to use a repeater in the communication transmission path. A conventional power line carrier communication repeater will be described below with reference to the drawings.

FIG. 3 is a block diagram of power line communication using a conventional power line communication repeater. A control device 2 and a terminal device 3 are connected on a power line 1 which is a transmission communication path. If a control request has occurred, the control device 2 transmits a control signal to the terminal device 3 via the power line 1. The terminal device 3 that received the control signal controls the connected electrical device 4 according to the contents of the message. As an example of the control content, 0N10FF control of the power supply can be considered. When attempting to control the terminal device 6 from the control device 2, if the impedance of the electrical device 4 is low, the signal on the power line is attenuated and cannot be reached, making it impossible to control the electrical device 6. Therefore, by inserting a repeater 7 in the middle of the power line 1, it is possible to transmit the signal to a long distance. The repeater 7 has the function of freely passing the power line power supply voltage between the terminals 8 and 9, amplifying the signal voltage input from the terminal 8, and outputting it from the terminal 9. In this way, by appropriately inserting the repeater 7 in the middle of the power line 1, it is possible to carry out power line communication over long distances.

Problems that the invention aims to solve Because conventional repeaters amplify signals input from one side and transmit them to the other, it is necessary to cut a part of the power line that is the transmission communication path before inserting the repeater. . Therefore, there is a problem in that a lot of labor is required to install a conventional repeater. Furthermore, if the installed repeater is installed in an inappropriate location, more labor will be required to relocate the repeater. In other words, there is also the problem that flexibility in changing the installation is poor.

The present invention solves these conventional problems and provides a repeater with good workability and flexibility.

Means for Solving the Problems The power line carrier communication repeater of the present invention includes a receiving means for receiving pulses, a pulse head detecting means connected to the receiving means and detecting the head of the pulse, and a pulse head detecting means for detecting the head of the pulse. The pulse generating means is connected to the pulse generating means and generates a pulse of a predetermined length after detecting the beginning of the pulse, and the transmitting means amplifies the pulse generated by the pulse generating means and transmits the amplified pulse onto the power line.

In the second configuration, pulses from the power line are input to the pulse head detecting means via the receiving means 6 and 7. If the leading edge of the pulse signal is detected here, the pulse generating means generates a pulse of a predetermined length, and this pulse is multiplied by the transmitting means.
] and transmitted over the power line.

Embodiment An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of an embodiment of a power line carrier communication repeater, which is connected in parallel to a power line a10. The receiving means 11 constituting the repeater receives power line carrier communication pulses consisting of high frequency signals transmitted from the control equipment. The received pulse is applied to pulse head detection means 12. Pulse head detection means 12
When detecting the leading edge of the pulse, it sends information to that effect to the pulse generating means 13. After detecting the leading edge of the pulse, the pulse generating means 13 generates a pulse of a predetermined length used in power line carrier communication. The generated pulse is amplified and transmitted from the transmitting means 14 to the power line 1o.

FIG. 2 shows waveforms at various parts of the configuration explained in FIG. 1. Waveform A is a high-frequency signal on a power line AC waveform 15. Pulses 16 and 17°1 of a constant pulse length T are made up of high-frequency signals 6 and 6.
8.19 is shown superimposed. Here, the pulse is in the first half of the half cycle of the power line AC waveform 15 (pulse 16.
17) in logic 1. What is in the second half (Pulse 18.19
) as logical 0 and combine them to create a message,
It controls each terminal device connected to the power line 10. Waveform B shows pulse 16. The pulse head detecting means 12 detects the head l of this pulse. This detection can be easily achieved by receiving the leading edge of the pulse for a short period of time. After detecting the leading edge e of the pulse, the pulse generating means 13 generates a pulse 2 having a predetermined pulse length TI, as shown by waveform C.
1 is generated and output from the transmitting means 14. Here TI=
Let it be T-1 dust T. That is, if the original pulse 16 is detected at its leading edge l, the time required for the detection is minimized, and the pulse length T' is made close to the pulse length T, the pulse 21 becomes the original pulse 16. It is almost a reproduction of. Here, when outputting to the power line 10, the original waveform B
The pulse on the power line at this point has approximately the original pulse length and position, and is amplified by the amplitude. This makes power line carrier communication possible over even greater distances.

In the above embodiment, communication using pulse position modulation was explained, but the idea of the present invention can be applied to any communication that uses pulses of a fixed length.

Effects of the Invention When installing the power line carrier communication repeater of the present invention, it is only necessary to connect it in parallel to a power line, for example, if there is an outlet, it is only connected there. Therefore, it has the effect of good workability. It is easy to change the installation location, and the rework FV including maintenance is also good. In addition, it is possible to easily increase or decrease the number of installations due to changes in the scale of the system, which has the effect of providing good flexibility regarding system changes.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a signal waveform diagram thereof, and FIG. 3 is a block diagram showing a conventional example. 1o... power line, 11... receiving means,
12...Pulse head detection means, 13...
- Pulse generation means, 14...transmission means.

Claims (1)

[Claims] In power line carrier communication that performs bidirectional communication by superimposing pulses consisting of high-frequency signals of a certain length on a power line, a receiving means for receiving the pulses and a pulse head detection unit connected to the receiving means and detecting the head of the pulses are used. a pulse generating means connected to the pulse head detecting means and generating a pulse of a predetermined length after detecting the pulse head; and a transmitting means amplifying the pulse generated by the pulse generating means and transmitting the amplified pulse onto a power line. A power line carrier communication repeater consisting of a power line and connected in parallel to a power line.