JP2008131303A - Power line carrier communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power line carrier communication system capable of performing effective power line carrier communication. <P>SOLUTION: A demultiplexer/mixer 22 receives a television signal received by an antenna 1 through a coaxial line and superposes the received television signal on a PLC signal modulated by a PLC modem to generate a superposed signal. A distributor 23 receives the superposed signal superposed by the first demultiplexer/mixer 22 through the coaxial line and distributes the received superposed signal. A demultiplexer/mixer 31 receives the superposed signal distributed by the distributor 23 through the coaxial line, demultiplexes the received superposed signal into the television signal and the PLC signal and outputs the demultiplexed television signal to a television receiver 6 through the coaxial line. The PLC modem 4 demodulates the PLC signal demultiplexed by the demultiplexer/mixer 31 and outputs the demodulated PLC signal to a terminal apparatus 5. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a power line carrier communication system for performing data communication using a power line wired in an office or a house, etc. and a coaxial cable for broadcasting.

  In recent years, a local area network (LAN) connecting a plurality of computers has been rapidly spread in offices and houses. In such a LAN, a communication cable (so-called LAN cable) is usually used as a communication medium for connecting computers. However, when a new LAN is introduced into an existing office or house, wiring work or In consideration of cost, power line communication (PLC) that performs data communication using indoor wiring (power line) for power supply may be employed.

Patent Document 1 discloses a home or office for the purpose of transmitting an electrical information signal to an electrical appliance requiring information (paragraph [0009], etc.) without separately wiring an electrical information transmission line in a building. In addition to supplying power to various places in the building via the power supply line, the power supply line in the building, etc., and the electric information transmission line inside and / or outside the building are combined. A centralized processing method for power supply and electrical information transmission that also transmits an electrical information signal transmitted from the information transmission line to the power supply line is disclosed (claim 1 and the like).
JP 2001-258081 A

  However, since the power line (power supply line in Patent Document 1) used for the PLC is not originally laid as a communication path, the wiring form (topology) is not defined and the transmission characteristics cannot be guaranteed. Also, communication such as electrical equipment connected to the power line generates noise in the PLC signal band (for example, 2 to 30 MHz, which is the frequency band of high-speed PLC signals), and the impedance of the electrical equipment is low in the PLC signal band. It does not have sufficient performance as a track.

  The objective of this invention is providing the power line carrier communication system and branching mixer which can perform favorable power line carrier communication.

  A power line carrier communication system according to the present invention includes a television signal receiving unit that receives a television signal, a first PLC that receives communication data transmitted via a predetermined network, modulates the communication data, and generates a PLC signal. A television signal received by the modem and the television signal receiver is received through a coaxial line, and the received television signal and the PLC signal generated by the first PLC modem are superimposed to generate a superimposed signal. A first demultiplexing mixer that receives the superimposed signal generated by the first demultiplexing mixer via a coaxial line, and distributes the received superimposed signal, and is distributed by the distributor. The received superimposed signal is received via a coaxial line, the received superimposed signal is demultiplexed into a television signal and a PLC signal, and the demultiplexed television signal is output to a television receiver via the coaxial line. And a second PLC modem that demodulates the PLC signal demultiplexed by the second demultiplexer and outputs the demodulated PLC signal to the first terminal device. 1).

  According to this configuration, the television signal and the PLC signal modulated by the first PLC modem are superimposed by the first branching mixer to generate a superimposed signal. Then, the superimposition signal is distributed by the distributor, the superimposition signal is demultiplexed into a television signal and a PLC signal by the second demultiplexer, and the demultiplexed television signal is output to the television receiver. Then, the PLC signal demultiplexed by the second demultiplexing mixer is demodulated by the second PLC modem and output to the first terminal device.

  That is, the PLC signal received by the first PLC modem is superimposed on the television signal to be a superimposed signal. Since this superimposed signal flows on the coaxial line, the coaxial line is superior as a communication line compared to the power line. It is possible to transmit a PLC signal using, and good power line carrier communication can be realized.

  The second PLC modem modulates communication data output from the first terminal device and generates a PLC signal, and the second demultiplexing mixer is generated by the second PLC modem. The superimposed PLC signal and the television signal are superimposed to generate a superimposed signal, and the first demultiplexing mixer receives the superimposed signal generated by the second demultiplexing mixer via the distributor. Then, the received superimposed signal is demultiplexed into a television signal and a PLC signal, and the demultiplexed PLC signal is output to the first PLC modem. The first PLC modem demodulates the first PLC signal. And output to the network.

  According to this configuration, the communication data output from the first terminal device is modulated into a PLC signal by the second PLC modem, and the PLC signal and the television signal modulated by the second PLC modem are The demultiplexed signal is demultiplexed by the first PLC modem. The demultiplexed PLC signal is demodulated by the first PLC modem. And output to the network. Therefore, the communication data output from the first terminal device can be satisfactorily transmitted by the PLC.

  In addition, it is preferable that a blocking filter for preventing a PLC signal from flowing from the first demultiplexing mixer to the television signal receiving unit side is provided.

  According to this configuration, it is possible to prevent a PLC signal from flowing from the first demultiplexing mixer to the television signal receiver, and when an antenna is used as the television signal receiver, the PLC is connected to the PLC. It is possible to prevent the signal from being radiated into the air.

  A first line that supplies power from the distribution board to the second PLC modem via a power outlet; and a branch point disposed between the power outlet and the distribution board in the first line. And a second line connecting the second demultiplexing mixer, and a leakage of the PLC signal to the distribution board side between the branch point and the distribution board in the first line It is preferable to further comprise a second blocking filter that prevents the above (claim 4).

  According to this configuration, it is possible to prevent leakage of the PLC signal to the distribution board side.

  The television signal receiver preferably includes an antenna that receives a television signal, and a booster that is disposed between the antenna and the first demultiplexer and amplifies the television signal. .

  According to this configuration, since the output impedance of the booster is high, it is possible to prevent the PLC signal from being radiated from the antenna into the air without providing a blocking filter between the antenna and the first demultiplexer.

  The TV signal receiving unit includes a booster that receives a cable TV downstream signal transmitted from a cable TV broadcasting station and outputs the cable TV upstream signal to the cable TV broadcasting station, and the cable output by the booster. A first bypass device that outputs a TV down signal to the first demultiplexer, a second terminal device connected to the second demultiplexer via a cable modem, and the second demultiplexer A second bypass device connected between the demultiplexing mixer and the cable modem; and a bypass line connecting between the first and second bypass devices, wherein the second bypass device includes the second bypass device, A cable television upstream signal output from the terminal device of 2 via the cable modem is output to the bypass line, and the first bypass device is configured to May output a cable television uplink signal outputted from the bypass unit to the cable television broadcast station (claim 6).

  According to this configuration, the cable TV upstream signal flows to the table television broadcasting station side through a bypass line different from the television signal, so that interference between the cable TV upstream signal and the PLC signal can be prevented. .

  The first terminal device includes a first radio device, converts the PLC signal demultiplexed by the second demultiplexer into a radio signal, and outputs the signal to the first radio device. It is preferable that a wireless device is provided (claim 7).

  According to this configuration, the PLC signal demultiplexed by the second demultiplexer can be transmitted to the first terminal device by radio.

  According to the present invention, good power line carrier communication can be performed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals denote the same components.

(Embodiment 1)
FIG. 1 shows an overall configuration diagram of a power line carrier communication system according to Embodiment 1 of the present invention. The power line carrier communication system includes an antenna 1 (television signal receiver), an information panel 2, an outlet box 3, a PLC modem 4 (second PLC modem), a terminal device 5 (first terminal device), and a distribution board 8 It has. The information board 2 includes a PLC modem 21 (first PLC modem), a demultiplexer / mixer 22 (first demultiplexer / mixer), and a distributor 23. The outlet box 3 includes a branching mixer 31 (second branching mixer), a television signal outlet 32, and a power outlet 33.

  Between antenna 1 and demultiplexing mixer 22, between demultiplexing mixer 22 and distributor 23, between distributor 23 and demultiplexing mixer 31, between demultiplexing mixer 31 and TV signal outlet 32, and TV signal outlet 32 and the television receiver 6 are connected by a coaxial line. The coaxial line is a coaxial line having a characteristic impedance of 75Ω used for transmission of a television signal.

  The PLC modem 21, the distribution board 8, and the branching mixer 22 are connected by a power line. The distribution board 8, the demultiplexing mixer 31, the power outlet 33, and the PLC modem 4 are connected by a power line. The PLC modem 21 and a predetermined network (for example, the Internet 7), and the PLC modem 4 and the terminal device are connected by a LAN cable.

  The antenna 1 receives a television signal. The PLC modem 21 receives communication data transmitted via the Internet 7, modulates the received communication data, and generates a PLC signal. The PLC modem 21 demodulates the PLC signal demultiplexed by the demultiplexing mixer 22 and outputs it to the Internet 7.

  The demultiplexing mixer 22 receives the television signal received by the antenna 1 through a coaxial line, and superimposes the received television signal and the PLC signal generated by the PLC modem 21 to generate a superimposed signal. Further, the demultiplexing mixer 22 receives the superimposed signal generated by the demultiplexing mixer 31 via the distributor 23, demultiplexes the received superimposed signal into a television signal and a PLC signal, and demultiplexes the PLC signal. Is output to the PLC modem 21.

  FIG. 2A is a block diagram showing a detailed configuration of the demultiplexing mixer 22. As shown in FIG. 2A, the demultiplexing mixer 22 includes terminals T11 to T13, a balun 221, and a low-pass filter 222. The terminal T11 is connected to the antenna 1, the terminal T12 is connected to the PLC modem 21 and the distribution board 8, and the terminal T13 is connected to the distributor 23.

  The low-pass filter 222 is connected to the terminal T11 via the line L11. The low-pass filter 222 is connected to the terminal T13 via a line L12 connected to the branch point P11 on the line L11. A low pass filter 222 and a balun 221 are connected in series in this order between the branch point P11 and the terminal T12. The balun 221 insulates the power line from the coaxial line and converts the signal from balanced transmission to unbalanced transmission. The low-pass filter 222 has a characteristic of attenuating a signal of 70 MHz or more and allowing a signal of 70 MHz or less to pass, and causes a 2 MHz to 30 MHz PLC signal to flow to the terminal T12, and a 70 MHz to 770 MHz television signal to flow to the terminal T12. Stop.

  The distributor 23 receives the superimposed signal superimposed by the demultiplexing mixer 22 via the coaxial line, and distributes the received superimposed signal. Specifically, a plurality of coaxial lines D11 to D14 are connected to the distributor 23, and the superimposed signal output from the demultiplexing mixer 22 is distributed to the coaxial lines D11 to D14. In FIG. 1, the outlet box 3 is connected only to the coaxial line D11, but actually, the outlet box 3 is also connected to each of the coaxial lines D12 to D14.

  The demultiplexing mixer 31 receives the superimposed signal distributed by the distributor 23 via a coaxial line, demultiplexes the received superimposed signal into a television signal and a PLC signal, and demultiplexes the television signal via the coaxial line. To the TV signal outlet 32. Further, the demultiplexing mixer 31 superimposes the PLC signal generated by the PLC modem 4 and the television signal to generate a superimposed signal, and outputs it to the distributor 23.

  FIG. 2B is a block diagram illustrating a detailed configuration of the demultiplexing mixer 31. As shown in FIG. 2B, the demultiplexing mixer 31 includes terminals T21 to T23, a balun 311 and a high-pass filter 312. The terminal T21 is connected to the distributor 23, the terminal T22 is connected to the distribution board 8 and the power outlet 33, and the terminal T23 is connected to the television signal outlet 32.

  The high pass filter 312 is connected between the terminal T21 and the terminal T23. The balun 311 is connected between the terminal T21 and the terminal T22. The balun 311 insulates the power line and the coaxial line and converts the signal from balanced transmission to unbalanced transmission. The high-pass filter 312 has a characteristic of allowing a signal of 70 MHz or more to pass and attenuating a signal of 70 MHz or less, causing a 70 MHz to 770 MHz television signal to flow to the terminal T23, and a 2 MHz to 30 MHz PLC signal to flow to the terminal T23. Stop.

  The TV signal outlet 32 is an outlet for connecting the TV receiver 6 and the demultiplexing mixer 31. The power outlet 33 is a household outlet to which a power plug included in a household electrical device is connected.

  The PLC modem 4 demodulates the PLC signal demultiplexed by the demultiplexing mixer 31 and outputs it to the terminal device 5 as communication data. In addition, the PLC modem 4 modulates the communication data output from the terminal device 5 into a PLC signal, and outputs the PLC signal to the demultiplexing mixer 31 via the power outlet 33.

  The terminal device 5 includes a personal computer connected to the PLC modem 4 via a LAN cable, and transmits and receives communication data. The distribution board 8 includes a breaker or the like, and supplies commercial power to the PLC modems 21 and 4.

  Next, an operation when the terminal device 5 receives communication data in the power line carrier communication system shown in FIG. 1 will be described. First, the antenna 1 receives a television signal, and the PLC modem 21 modulates communication data transmitted via the Internet 7 to generate a PLC signal. Next, the demultiplexing mixer 22 superimposes the television signal received by the antenna 1 and the PLC signal modulated by the PLC modem 21 to generate a superimposed signal. Next, the distributor 23 distributes the superimposed signal generated by the branching mixer 22. Next, the demultiplexing mixer 31 demultiplexes the superposed signal distributed by the distributor 23 into a television signal and a PLC signal, and the demultiplexed television signal is sent to the television receiver 6 via the television signal outlet 32. Output. Next, the PLC modem 4 demodulates the PLC signal demultiplexed by the demultiplexing mixer 31 and outputs it to the terminal device 5.

  Next, the operation when the terminal device 5 transmits communication data in the power line carrier communication system shown in FIG. 1 will be described. First, the terminal device 5 outputs communication data to the PLC modem 4. Next, the PLC modem 4 modulates the communication data output from the terminal device 5 and generates a PLC signal. Next, the demultiplexing mixer 31 receives the PLC signal generated by the PLC modem 4 via the power outlet 33, and superimposes the received PLC signal on the television signal to generate a superimposed signal. Next, the demultiplexing mixer 22 receives the superimposed signal generated by the demultiplexing mixer 31 via the distributor 23 and demultiplexes the received superimposed signal into a television signal and a PLC signal. Next, the PLC modem 21 demodulates the demultiplexed PLC signal and outputs it to the Internet 7.

  As described above, according to the power line carrier communication system according to the present embodiment, the PLC signal received by the PLC modem 21 is superimposed on the television signal to be a superimposed signal, but this superimposed signal flows on the coaxial line. In addition, it is possible to transmit a PLC signal using a coaxial line that is superior as a communication line compared to a power line, and it is possible to realize good power line carrier communication.

(Embodiment 2)
Next, a power line carrier communication system according to Embodiment 2 of the present invention will be described. FIG. 3 is an overall configuration diagram of the power line carrier communication system according to the second embodiment. The power line carrier communication system according to the second embodiment is characterized in that, in the power line carrier communication system according to the first embodiment, a blocking filter 24 (first blocking filter) is provided between the antenna 1 and the demultiplexing mixer 22. To do.

  The blocking filter 24 prevents the PLC signal from flowing from the demultiplexing mixer 22 to the antenna 1 side. FIG. 4 is a diagram showing a detailed configuration of the blocking filter 24. As shown in FIG. 4, the blocking filter 24 includes a high pass filter 241. The high-pass filter 241 is a high-pass filter that has a characteristic of blocking a PLC signal of 2 to 30 MHz and allowing a television signal of 70 MHz to 770 MHz to pass.

  As described above, according to the power line carrier communication system according to the second embodiment, since the blocking filter 24 is provided between the antenna 1 and the demultiplexing mixer 22, it is possible to prevent the PLC signal from flowing to the antenna 1 side. The PLC signal can be prevented from radiating from the antenna 1 into the air.

(Embodiment 3)
Next, a power line carrier communication system according to Embodiment 3 will be described. FIG. 5 shows an overall configuration diagram of a power line carrier communication system according to the third embodiment. In the power line carrier communication system according to the third embodiment, in the power line carrier communication system according to the second embodiment, a booster 25 (television signal receiving unit) is arranged instead of the blocking filter 24, and between the distribution board 8 and the PLC modem 21. And a blocking filter 34 (second blocking filter) is disposed between the distribution board 8 and the power outlet 33.

  The booster 25 is a TV signal booster that amplifies the television signal received by the antenna 1 and outputs the amplified signal to the demultiplexing mixer 22a.

  The blocking filter 26 prevents the PLC signal generated by the PLC modem 21 and the PLC signal demultiplexed by the demultiplexing mixer 22 from leaking to the distribution board 8 side. FIG. 6B is a diagram showing a detailed configuration of the blocking filter 26. As shown in FIG. 6B, the blocking filter 26 is composed of a high cut filter HCF (High Cut Filter). The high cut filter HCF has a characteristic of passing an AC signal (50 Hz, 60 Hz) and attenuating the PLC signal.

  The blocking filter 34 prevents the PLC signal generated by the PLC modem 4 and the PLC signal demultiplexed by the demultiplexing mixer 31 from leaking to the distribution board 8 side. The blocking filter 34 is constituted by a high cut filter HCF shown in FIG.

  The power line L31 supplies the power from the distribution board 8 to the PLC modem 4 via the power outlet 33. The branch point P31 is disposed between the power outlet 33 and the distribution board 8 in the power line L31. The power line L32 connects the branch point P31 and the demultiplexing mixer 31a. The blocking filter 34 is disposed between the branch point P31 and the distribution board 8 in the power line L31.

  FIG. 6A is a diagram showing a detailed configuration of the demultiplexing mixer 22a. As shown in FIG. 6A, the demultiplexing mixer 22a is a high pass between the terminal T11 (first terminal) and the terminal T13 (third terminal) in the demultiplexing mixer 22 shown in FIG. The filter 312 is arranged. The terminal T13 is connected to the booster 25, the terminal T12 (second terminal) is connected to the PLC modem 21 and the blocking filter 26, and the terminal T11 is connected to the distributor 23. Here, the high-pass filter 312 shown in FIG. 6A is the same as the high-pass filter 312 shown in FIG. The high pass filter 312 and the low pass filter 222 correspond to an example of a superimposing unit.

  If the demultiplexing mixer 22a is configured as shown in FIG. 6A, the demultiplexing mixer 22a and the demultiplexing mixer 31a can have the same configuration.

  That is, the demultiplexing mixer 31a has a configuration in which the low pass filter 222 is arranged between the terminal T11 and the balun 311 in the demultiplexing mixer 31 shown in FIG. Then, as shown in FIG. 6A, the demultiplexing mixers 22a and 31a are configured, the terminal T13 is connected to the booster 25, the terminal T12 is connected to the PLC modem 21, and the terminal T11 is connected to the distributor 23. , The terminal T21 is connected to the distributor 23, the terminal T22 is connected to the power outlet 33, and the terminal T23 is connected to the television signal outlet 32, so that the demultiplexing mixer shown in FIGS. Since the same operation as 22 and 31 can be achieved, the demultiplexers 22a and 31a can be shared, and the cost can be reduced.

  As described above, according to the power line carrier communication system according to the third embodiment, since the blocking filters 26 and 34 are provided, it is possible to prevent the PLC signal from leaking to the distribution board 8 side. Further, since the booster 25 is provided and the impedance on the output side of the booster 25 is high, the PLC signal can be prevented from flowing to the antenna 1 side, and the antenna 1 can be provided without providing the blocking filter 24 as shown in FIG. It is possible to prevent the PLC signal from being radiated into the air. In addition, as a booster 25, you may employ | adopt the thing into which the television signal transmitted from a table television broadcasting station is input instead of the thing into which the television signal received by the antenna 1 is input.

(Embodiment 4)
Next, a power line carrier communication system according to the fourth embodiment will be described. FIG. 7 shows an overall configuration diagram of a power line carrier communication system according to the fourth embodiment. The power line carrier communication system according to the fourth embodiment is the same as the power line carrier communication system according to the third embodiment. The information panel 2 includes a bypass device 27 (first bypass device), and the outlet box 3 includes a bypass device 35 (second bypass device). And a booster 25 is input with a cable TV down signal transmitted from a cable TV broadcasting station instead of a TV signal from the antenna 1.

  The booster 25 (TV signal receiving unit) receives a cable TV downstream signal transmitted from a cable TV broadcasting station, amplifies the input cable TV downstream signal, and amplifies the cable TV upstream signal to a cable TV broadcasting station. Output to.

  The bypass device 27 outputs the cable television down signal output from the booster 25 to the demultiplexing mixer 22a, and the cable television up signal output from the bypass device 35 via the bypass line 11 via the booster 25. Output to cable TV station.

  FIG. 8 is a diagram showing a detailed configuration of the bypass device 27. As shown in FIG. 8, the bypass device 27 includes terminals T31 to T33, a high-pass filter 271, and a low-pass filter 272. The terminal T31 is connected to the booster 25, the terminal T32 is connected to the bypass line 11, and the terminal T33 is connected to the demultiplexing mixer 22a. The high-pass filter 271 is connected between the terminal T31 and the terminal T33, has a characteristic of passing a signal of 70 MHz or higher and attenuating a signal of 55 MHz or lower, and allows a cable TV downstream signal input to the terminal T31 to flow to the terminal T33. At the same time, the cable television upstream signal input to the terminal T32 is prevented from flowing to the terminal T33.

  The low-pass filter 272 is connected between the terminal T31 and the terminal T32, and has a characteristic of passing a signal of 55 MHz or less and attenuating a signal of 70 MHz or more. The low-pass filter 272 sends the cable TV upstream signal input to the terminal T32 to the terminal T31. The cable TV down signal input to the terminal T31 is prevented from flowing to the terminal T32.

  The bypass device 35 is connected between the demultiplexing mixer 31 a and the TV signal outlet 32, and outputs the cable TV upstream signal output from the terminal device 10 via the cable modem 9 and the TV signal outlet 32 to the bypass line 11. To do.

  FIG. 8 is a diagram showing a detailed configuration of the bypass device 35. In FIG. 8, a symbol in parentheses indicates the bypass device 35. As shown in FIG. 8, the bypass device 35 includes terminals T41 to T43, a high-pass filter 351, and a low-pass filter 352.

  The terminal T41 is connected to the cable modem 9 via the television signal outlet 32, the terminal T42 is connected to the bypass line 11, and the terminal T43 is connected to the demultiplexing mixer 31a. The high-pass filter 351 is a high-pass filter that is connected between the terminal T41 and the terminal T43 and has the same characteristics as the high-pass filter 271. The cable TV downstream signal input to the terminal T43 flows to the terminal T41 and is input to the terminal T41. Cable TV upstream signal is prevented from flowing to terminal T43.

  The low-pass filter 352 is a low-pass filter that is connected between the terminal T41 and the terminal T42 and has the same characteristics as the low-pass filter 272. The low-pass filter 352 sends the cable TV upstream signal input to the terminal T41 to the terminal T42 and is input to the terminal T43. The cable TV down signal is prevented from flowing to the terminal T42.

  FIG. 9 shows frequency characteristics of the PLC signal, the cable TV upstream signal, and the cable TV downstream signal. As shown in FIG. 9, the frequency band of the PLC signal is 2 MHz to 30 MHz, and the frequency band of the cable television upstream signal is 10 MHz to 55 MHz. Therefore, both signals overlap the band of 10 MHz to 30 MHz. Therefore, if the terminal device 5 that communicates with the PLC signal and the terminal device 10 that communicates with the cable TV upstream signal are provided side by side and both signals flow on the same line, both signals will interfere and perform good communication. There is a risk that it will be impossible. Therefore, in the present embodiment, a band of 30 MHz or more of the cable TV upstream signal is sent to the bypass line 11 so that the PLC signal and the cable TV upstream signal do not flow on the same line, and good communication by both signals is performed. Realized.

  The terminal device 10 (second terminal device) is composed of a personal computer and is connected to the TV signal outlet 32 via the cable modem 9 to transmit and receive communication data.

  The cable modem 9 is connected to the terminal device 10 via a LAN cable, and is connected to a television signal outlet 32 via a coaxial line. The cable modem 9 modulates communication data transmitted from the terminal device 10 and transmits a cable TV upstream signal. Is output to the TV signal outlet 32, and the cable TV downstream signal output from the TV signal outlet 32 is demodulated and output to the terminal device 10 as communication data.

  The bypass line 11 is composed of a coaxial line used for transmitting television signals, and is connected between the bypass device 27 and the bypass device 35.

  As described above, according to the power line carrier communication system according to the present embodiment, the cable TV upstream signal flows to the table television broadcasting station side through the bypass line on a different path from the television signal. Interference with the PLC signal can be prevented.

(Embodiment 5)
Next, a power line carrier communication system according to the fifth embodiment will be described. FIG. 10 shows an overall configuration diagram of a power line carrier communication system according to the fifth embodiment. The power line carrier communication system according to Embodiment 5 is characterized in that the terminal device 5 transmits and receives communication data wirelessly.

  As shown in FIG. 10, the power line carrier communication system according to the fifth embodiment is the same as the power line carrier communication system according to the first embodiment, except that a booster 25 is connected between the demultiplexing mixer 22 and the antenna 1. A wireless device 36 (second wireless device) is connected, and the terminal device 5 includes a wireless device 51 (first wireless device).

  The radio device 36 converts the PLC signal demultiplexed by the demultiplexing mixer 31 into a radio signal and outputs the radio signal to the radio device 51. Here, the wireless device 36 transmits and receives wireless signals in accordance with a communication method such as wireless communication (for example, applied wireless USB) using UWB (Ultra Wide Band), which is an ultra-wideband wireless technology, or a wireless LAN (IEEE802.11a, etc.). . The wireless device 51 transmits and receives wireless signals according to the same communication method as the wireless device 36.

  Thus, according to the power line carrier communication system of the fifth embodiment, the terminal device 5 can transmit and receive communication data wirelessly.

1 shows an overall configuration diagram of a power line carrier communication system according to Embodiment 1 of the present invention. FIG. (A) is a block diagram showing a detailed configuration of the demultiplexing mixer 22, and (b) is a block diagram showing a detailed configuration of the demultiplexing mixer 31. FIG. 3 shows an overall configuration diagram of a power line carrier communication system according to a second embodiment. It is the figure which showed the detailed structure of the blocking filter. FIG. 5 is an overall configuration diagram of a power line carrier communication system according to a third embodiment. (A) is a figure which shows the detailed structure of a demultiplexing mixer, (b) is the figure which showed the detailed structure of the blocking filter. FIG. 6 shows an overall configuration diagram of a power line carrier communication system according to a fourth embodiment. It is a figure which shows the detailed structure of a bypass apparatus. The frequency characteristics of a PLC signal, a cable television upstream signal, and a cable television downstream signal are shown. FIG. 7 shows an overall configuration diagram of a power line carrier communication system according to a fifth embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna 2 Information panel 3 Outlet box 4 PLC modem 5 Terminal device 6 Television receiver 7 Internet 8 Distribution board 9 Cable modem 10 Terminal device 11 Bypass line 21 PLC modem 22, 22a Demultiplexing mixer 31, 31a Demultiplexing mixer 23 Distributor 24, 26, 34 Blocking filter 25 Booster 27, 35 Bypass device 32 Television signal outlet 33 Power outlet 36 Wireless device 51 Wireless device 221, 311 Balun 222, 272, 352 Low pass filter 241, 271, 312, 351 High pass Filters D11 to D14 Coaxial lines L11 and L12 Lines L31 and L32 Power line

Claims (7)

A television signal receiver for receiving television signals;
A first PLC modem that receives communication data transmitted via a predetermined network, modulates the communication data, and generates a PLC signal;
A television signal received by the television signal receiving unit is received via a coaxial line, and the received television signal and the PLC signal generated by the first PLC modem are superimposed to generate a superimposed signal. A demultiplexer of
A distributor for receiving the superimposed signal generated by the first demultiplexing mixer via a coaxial line and distributing the received superimposed signal;
The superimposed signal distributed by the distributor is received via a coaxial line, the received superimposed signal is demultiplexed into a television signal and a PLC signal, and the demultiplexed television signal is output to a television receiver via the coaxial line. A second demultiplexer;
A power line carrier communication system, comprising: a second PLC modem that demodulates a PLC signal demultiplexed by the second demultiplexer and outputs the demodulated PLC signal to a first terminal device. The second PLC modem modulates communication data output from the first terminal device to generate a PLC signal,
The second branching mixer generates a superimposed signal by superimposing the PLC signal generated by the second PLC modem and the television signal,
The first demultiplexing mixer receives the superimposed signal generated by the second demultiplexing mixer via the distributor, demultiplexes the received superimposed signal into a television signal and a PLC signal, and demultiplexes them. Outputting the waved PLC signal to the first PLC modem;
The power line carrier communication system according to claim 1, wherein the first PLC modem demodulates the first PLC signal and outputs the demodulated signal to the network.   3. The power line carrier communication system according to claim 1, further comprising a blocking filter that prevents a PLC signal from flowing from the first demultiplexer to the television signal receiver. A first line for supplying power from the distribution board to the second PLC modem via a power outlet;
A second line connecting the branch point disposed between the power outlet and the distribution board in the first line, and the second branching mixer;
2. A second blocking filter disposed between the branch point and the distribution board in the first line and further preventing a PLC signal from leaking to the distribution board side. The power line carrier communication system according to any one of items 1 to 3.   The said television signal receiving part is equipped with the booster which is arrange | positioned between the antenna which receives a television signal, and the said antenna and the said 1st demultiplexing mixer, and amplifies a television signal. 3. The power line carrier communication system according to 2. The TV signal receiving unit is provided with a booster that outputs a cable TV upstream signal to the cable TV broadcast station, as well as a cable TV downstream signal transmitted from the cable TV broadcast station.
A first bypass device that outputs the cable TV downstream signal output by the booster to the first demultiplexer;
A second terminal device connected to the second branching mixer via a cable modem;
A second bypass device connected between the second branching mixer and the cable modem;
Further comprising a bypass line connecting between the first and second bypass devices,
The second bypass device outputs a cable TV upstream signal output from the second terminal device via the cable modem to the bypass line,
The power line carrier communication system according to claim 1 or 2, wherein the first bypass device outputs a cable television upstream signal output from the second bypass device to the booster. The first terminal device includes a first wireless device;
7. A second radio apparatus that converts a PLC signal demultiplexed by the second demultiplexer into a radio signal and outputs the radio signal to the first radio apparatus. The power line carrier communication system according to any one of the items.

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