JPS6232651B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a signal relay system in a power line transport system.

FIG. 1 is a schematic circuit block diagram of a power line transport system. In the figure, a transmitter 1 and a receiver 2 are connected to a commercial power line 3, respectively. Transmitter 1
modulates the carrier wave with a control signal for receiver 2,
It is transmitted to the commercial power line 3 which is a signal line. The waveform on this commercial power line 3 is shown in FIG. A control signal 4 in the form of a high frequency signal is superimposed on a waveform 5 of the commercial power source. FIG. 3 shows the signal format of the transmitter 1, in which the control signal 4 includes a start mark 6 indicating the start of the signal;
It consists of a channel code 7 indicating which receiver 2 the control signal 4 is directed to, and a control code 8 indicating the content of the control.

By the way, when long-distance transmission is performed using the power line transport system described above, signal attenuation in the commercial power line 3, which is a transmission line, becomes a major problem.
Therefore, a method has been proposed that uses a repeater to return the signal to its original level midway through the process. A schematic circuit block diagram of this method is shown in FIG. 4, where 9 is a repeater. Briefly explaining the function of this repeater 9, the control signal 4 transmitted from the transmitter 1 is attenuated at the connection point of the receiver 2, so that it cannot be directly received. The repeater 9 receives the control signal 4 from the transmitter 1 and temporarily stores it. After the transmitter 1 finishes transmitting, the repeater 9 starts transmitting and retransmits the same signal 4' as the control signal 4 previously transmitted by the transmitter 1. Since repeater 9 is closer to receiver 2 than transmitter 1, receiver 2
receives the signal from the repeater 9 and operates. FIG. 5 shows the transmission timing of each transmission signal of the transmitter 1 and the receiver 2. Figure 1a shows the transmitted number of the transmitter 1, and Figure b shows the transmitted number of the repeater 9, respectively. By the way, the function of the repeater 9 is to receive the control signal 4 from the transmitter 1, temporarily store it, and when the control signal 4 disappears on the commercial power line 3, transmit the same signal 4' as the stored control signal 4. It is something. Therefore, there was a problem when using two repeaters 9 to extend the transmission distance. This problem is caused by the fact that when there are multiple repeaters 9, one repeater 9 naturally also relays the signals relayed by the other repeaters 9, but two repeaters 9
are in positions where they can transmit information to each other, the same operation is repeated over and over again. FIG. 6 shows a circuit block diagram using two repeaters 9. In the figure, the control signal 4 transmitted from the transmitter 1 is transmitted to the repeater 9.
₁ , 9, _{and 2} , and transmitted to the receiver 2. The problem here is that if the signal 4' from repeater ₉₁ is relayed and transmitted by repeater ₉₂ ,
₁ receives the signal 4' from the repeater ₉₂ again and relays it again. Therefore, the control signal 4 transmitted from the transmitter 1 in FIG. 7a is alternately and permanently relayed between the repeaters ₉₁ and ₉₂ . 7b shows the transmitting number 4' of the repeater ₉₁ , and FIG. 7c shows the transmitting number 4'' of the repeater ₉₂ .

Next, the transmitter 1 is connected between the two repeaters ₉₁ and ₉₂ .
Considering a case (shown in FIG. 8), in this case, the control signal 4 <FIG. 9 a> from the transmitter 1 can be received by both the repeaters 9 ₁ and 9 ₂ , so the repeater 9
₁ and 9 ₂ start relay transmission at the same time. 9th
Figure b shows the transmission number 4' of repeater _9-1 , and figure c shows the transmission number 4'' of repeater _9-2.By the way, when relay transmission is carried out at two places at the same time, interference occurs and mutual interference occurs. There was a problem in that signals 4' and 4'' interfered with each other and normal transmission could not be carried out.

When a plurality of repeaters 9 are used as described above, depending on the position of the transmitter 1, the relay transmission may become an endless loop and the transmission may not be completed, or interference may occur.

The present invention has been made in view of the above-mentioned problems, and its purpose is to enable relay transmission of control signals in a power line transport system without causing any trouble, thereby increasing the reliability of transmission. The present invention provides a signal relay method in a power line transport system.

The present invention will be explained below with reference to Examples.

First, the transmitter 1 used in the system of the present invention includes, for example, a CPU 10 and a receiver 11 as shown in FIG.
When an operation button of the transmission operation section 13 is operated, a control signal 4 including a channel code 7 and a control code 8 corresponding to the operation button is generated by the control operation of the CPU 10. The transmitter 12 then superimposes the signal on the waveform 5 of the commercial power source as shown in FIG. On the other hand receiver 2
As shown in FIG. 11, the transmitter 1 shown in FIG.
The control signal 4 superimposed on the power line 3 is received by the receiver 11', and if the channel code 7 is present in the control signal 4, the control code 8 is taken in and controlled by the control operation of the CPU 10. The relay 5 is operated via the drive circuit 26 to turn the external load on or off, and at the same time a return signal is sent back to the transmitter 1 from the transmitter 12'. The transmitter 1 is a receiver 11
A return signal is received by the CPU 10, and an operation display lamp provided corresponding to an operation button of the transmission operation section 13 is turned on by the operation of the CPU 10, for example. In the receiver 2, the channel setting section 14 can arbitrarily set the channel. By the way, the control signal 4 is formed according to a program stored in advance in the CPU 10, and in the first invention, the control signal 4 includes 4 bits in addition to the control code 8, channel code 7, and start mark 6. It is programmed to newly add relay mode code 15. FIG. 12 shows the signal format of the control signal 4. Then, the transmitter 1 forms an initial value in which the logical value of each bit of the relay mode code 15 is "0000" and transmits it. On the other hand, the repeater 9 used in the first invention is the 13th
As shown in the figure, the signal received by the receiving section 16 is temporarily held in the data memory 17, and the receiving section 16
The presence of the control signal 4 on the power line 3 is detected, and if the control signal 4 is not present, the transmitting section 18 relays the control signal 4. However, the relay mode code 15 in the control signal 4 received by the verification circuit section 19 The logic of a predetermined bit is tested, and if the logic value of the predetermined bit is the initial value "0", the transmitter 18 is controlled so that the logic value of that bit is inverted to "1" and transmitted at the time of the above-mentioned relay transmission. Conversely, if the logical value of the predetermined bit is "1", it is determined that the control signal 4 from the repeater 9 is being received, and the transmitter 18 is controlled to stop transmitting. ing. The bits tested by the verification circuit 9 are different for each repeater. For example, in the system shown in FIG. 6, the test bit of the repeater ₉₁ is the least significant bit, and during relay transmission, A relay mode code 15 of 1” is created. The verification bit of the repeater ₉₂ is the second bit from the lowest, and a relay mode code 15 of "xx1x" is created at the time of relay transmission. If the operating program of the receiver 2 is set to be controlled only by the channel code 7 and the control code 8 regardless of the contents of the relay mode 15, the connection relationship shown in FIG. 6 will be obtained. In the system, each repeater 9 ₁ , 9 ₂ verifies a predetermined bit of the relay mode code 15 of the control signal 4 received by each repeater 9 ₁ , 9 ₂ .
Even if the repeater receives a control signal that has already been relayed, it does not repeat the relay, thereby preventing the repeater from falling into an endless loop.

FIG. 14 shows a circuit diagram of a repeater 9 according to an embodiment of the second invention for preventing troubles in the system connected as shown in FIG. 4, the transmission detection signal from the receiver 23 is input to the PE terminal, and during this input, the priority setting switch 21
The setting inputs P ₂ , P ₁ , P ₀ are used as data, and the receiving section 23
When there is no longer a detection signal during transmission from the transmitter, the counter counts down, and when the count reaches "0", transmission can start. Therefore, the initial value of the down counter 20 (a value determined by the setting of the priority setting switch 21)
By increasing , it is possible to set a longer time from when signal reception ends to when relay transmission starts. 22 is a data memory for storing the data of each received signal received by the receiving section 23; 24 is a transmitting section; this transmitting section 24 is enabled by a transmission enable signal from the down counter 20; There is. Reference numeral 25 denotes a gate for controlling input of the clock pulse CP to the clock input terminal CK of the down counter 20.

In the system of FIG. 8, when the control signal 4 is transmitted from the transmitter 1 as shown in FIG. 15a,
Both repeaters 9 ₁ and 9 ₂ receive the control signal 4, and one repeater 9 ₁ receives the control signal 4 after a preset transmission delay time t ₁ from the timing when the transmission detection signal disappears, as shown in FIG. 15b. On the other hand, since the transmission delay time of repeater _9-2 is set to _t2 , which is longer than _t1 , when the transmission of repeater _9-1 starts, the transmission of repeater _9-2 starts as shown in Fig. 15c. It is not possible to transmit at the broken line position, and the transmission from repeater 9 ₁ stops and the transmission delay time t ₂ elapses, when repeater 9
₂ relay transmission will be performed as shown in FIG. 15c. Therefore, it is possible to prevent interference from occurring in the system shown in FIG.

It goes without saying that if the repeater 9 that combines the first invention and the second invention is used, troubles during relaying can be prevented in both the systems of FIG. 6 and FIG. 8.

The first invention adds a relay mode code for repeater identification to a control signal, assigns each bit of the relay mode code to a repeater connected between a transmitter and a receiver on a one-to-one basis, and performs relay transmission. a signal forming means for inverting the logical value of the assigned bits of the relay mode code with respect to the initial value of the relay mode code transmitted from the transmitter; and determining whether the assigned bits of the relay mode code of the received control signal are at the initial value. Since each repeater is equipped with a verification means that determines if the transmission is true and stops the relay transmission if it is not, for example, even if multiple repeaters are placed between the transmitter and the receiver and the relay is performed, the relay will not be transmitted. By verifying the mode code, it is possible to prevent re-relaying of control signals that have already been relayed by the relevant repeater, and as a result, a loop in which repeating is performed infinitely between repeaters is prevented, and control signals are reliably transmitted. This has the effect that relaying can be performed and long-distance transmission is possible without any trouble.

Further, in the second invention, a setting means for setting a transmission delay time from when a control signal disappears on the power line until relay transmission is provided is provided in each repeater connected to the power line, and the transmission delay time of each repeater is individually set. Since the transmission start order is set by adjusting the settings of the setting means so that the transmission start order is different, it is possible to reduce the interference that occurs when each repeater performs relay transmission at the same time, for example in a system where repeaters are placed on both sides of a transmitter. This can be prevented by using different transmission delay times, resulting in the effect that long-distance transmission can be performed without interference.

[Brief explanation of the drawing]

Figure 1 is a circuit block diagram of the basic system, Figure 2
The figure is a waveform diagram for explaining the operation as above, Figure 3 is a diagram for explaining the signal format as above, Figure 4 is a circuit block diagram using one repeater, and Figures 5a and b are for explaining the operation as above. Fig. 6 is a circuit block diagram of a system with multiple repeaters, Fig. 7 a to c are time charts for explaining the conventional operation of the same as above, and Fig. 8 is a circuit diagram of a system with multiple repeaters. FIGS. 9a to 9c are time charts for explaining the conventional operation of the same system, FIG. 10 is a schematic circuit block diagram of the transmitter used in the present invention, and FIG. 11 is a receiver used in the present invention. FIG. 12 is a diagram explaining the signal format of the control signal according to an embodiment of the first invention, FIG. 13 is a schematic circuit block diagram of the repeater used in the above, and FIG. A schematic circuit block diagram of a repeater according to an embodiment, and FIGS. 15a to 15c are time charts for explaining the operation of the same as above, in which 1 is a transmitter, 2 is a receiver, 3 is a power line, 4 is a control signal, and 7
is the channel code, 8 is the control code, 9 ₁ , 9
₂ is a repeater, 15 is a relay mode code, 20 is a down counter, 21 is a priority setting switch, 2
2 is a data memory.

Claims (1)

[Claims] 1. A control signal having a channel code and a control code is superimposed and conveyed from a transmitter to a power line, and a repeater connected to the power line between the transmitter and receiver receives and holds the control signal to generate power. In a power transfer system that relays and transmits a control signal from a repeater when there is no control signal on the line, a relay mode code for identifying the repeater is added to the control signal, and each bit of the relay mode code is transmitted between the transmitter and receiver. a signal forming means that allocates one-to-one to the relay mode code connected to the relay mode code on a one-to-one basis and inverts the logical value of the allocated bit of the relay mode code with respect to the initial value of the relay mode code transmitted from the transmitter during relay transmission; A power line carrier characterized in that each repeater is equipped with a verification means for determining whether the assigned bit of the relay mode code of the received control signal is the initial value or not, and stopping the relay transmission if not. Signal relay method in control system. 2 A control signal having a channel code and a control code is superimposed and conveyed from a transmitter to a power line, and a repeater connected to the power line receives and holds the control signal, and when there is no control signal on the power line, the repeater transmits the control signal. In a power line transport system that performs relay transmission, each repeater connected to the power line is provided with a setting means for setting the transmission delay time from when a control signal disappears on the power line until the relay transmission occurs, and the transmission delay of each repeater is provided. 1. A signal relay method in a power line carrier control system, characterized in that the transmission start order is set by setting and adjusting a setting means so that the times are different from each other.