JP2005142804A - Power line carrier communication apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a power line carrier communication apparatus that prevents the power consumption of a receiving amplifier from increasing due to the input of its own transmission to a reception means at transmission. <P>SOLUTION: The power line carrier communication apparatus is provided with: a transmission / reception section 1 for outputting a transmission signal and receiving a reception signal; a transmission amplifier 2 whose output terminal is coupled to a power line 5 and for amplifying the transmission signal from the transmission / reception section 1 and transmitting the amplified signal to the power line; and a reception amplifier 7 whose input terminal is coupled to the power line 5 and for amplifying the received signal from the power line 5 and transmitting the amplified received signal to the transmission / reception section 1, and the communication apparatus bypasses the reception amplifier 7 to input the transmission signal to the transmission / reception section 1 at transmission and shuts off a power supply voltage applied to the reception amplifier 7. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a power line carrier communication device such as a power line carrier modem.

  FIG. 4 shows a conventional power line carrier communication device taking a power line carrier communication repeater as an example. The power line carrier communication repeater is connected to the power line 10 in parallel. The receiving means 11 constituting the repeater receives the power line carrier communication pulse including the high frequency signal transmitted from the control device via the power line 10. The received pulse is applied to the pulse head detection means 12. When the pulse head detection means 12 detects the head of the pulse as a pulse after receiving it for a finite time, it sends information to that effect to the pulse generation means 13.

  The pulse generation means 13 generates a pulse having a length of time from the time of detection to the scheduled end of the pulse after detection of the head of the pulse, and can be realized by, for example, a monostable multivibrator. The generated pulse is amplified from the transmission means 14 and transmitted to the power line 10 (see, for example, Patent Document 1).

Japanese Examined Patent Publication No. 7-46793 (FIG. 1)

  The pulse transmission signal output from the transmission unit 14 is transmitted to the power line 10 and is fed back to the reception unit 11 at that time. This is unavoidably fed back, but alternatively, it may be fed back to the receiving means 11 in order to monitor the transmission signal. In any case, its own transmission signal is input to the receiving means 11. Since the receiving means 11 is provided with an amplifier for amplifying a transmission signal from the communication partner (reception signal for the receiving side), this amplifier is excited by the transmission signal when its own transmission signal is fed back during transmission. As a result, power consumption increases.

  An object of the present invention is to prevent an increase in power consumption in a receiving amplifier due to an input of its own transmission signal to a receiving means during transmission.

  In order to solve the above problems, a transmission / reception unit that outputs a transmission signal and receives a reception signal, an output terminal coupled to a power line, a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends the transmission signal to the power line, A reception amplifier coupled to the power line and amplifying a reception signal from the power line and sending the transmission signal to the transmission / reception unit, and bypassing the reception amplifier during transmission to transmit / receive the transmission signal The power supply voltage supplied to the receiving amplifier was cut off.

  A transmission / reception unit that outputs a transmission signal and receives the reception signal; an output end coupled to a power line; a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends the transmission signal to the power line; A reception amplifier that is coupled to a power line and amplifies a reception signal from the power line and transmits the amplified signal to the transmission / reception unit. A switch means is provided at an input terminal of the reception amplifier, and the reception amplifier is bypassed during transmission. The transmission signal is input to the transmission / reception unit, and the input of the transmission signal is blocked by the switch means.

  Further, the power supply voltage supplied to the receiving amplifier was cut off.

  A transmission / reception unit that outputs a transmission signal and receives the reception signal; an output end coupled to a power line; a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends the transmission signal to the power line; A reception amplifier coupled to a power line and amplifying a reception signal from the power line and transmitting the amplified signal to the transmission / reception unit, the transmission signal output from the transmission amplifier at the time of transmission via the attenuator Input to the amplifier.

  In addition, a switch means is provided at the input terminal of the reception amplifier, and the attenuator is connected in parallel to the switch means, and the switch means is turned off during transmission.

  As described above, according to the power line carrier communication device of the first aspect, the transmission signal is output and the transmission / reception unit that receives the reception signal and the output end are coupled to the power line, and the transmission signal from the transmission / reception unit is amplified. A transmission amplifier for transmitting to the power line, and a reception amplifier whose input terminal is coupled to the power line, amplifies the reception signal from the power line and transmits it to the transmission / reception unit, and bypasses the reception amplifier during transmission to transmit the signal. Since the power supply voltage supplied to the reception amplifier is cut off, the transmission signal can be monitored and power consumption in the reception amplifier can be completely eliminated.

  According to the power line carrier communication apparatus of claim 2, the transmission / reception unit that outputs the transmission signal and receives the reception signal and the output end are coupled to the power line, and the transmission signal from the transmission / reception unit is amplified to the power line. A transmission amplifier for transmission, and a reception amplifier whose input terminal is coupled to the power line, amplifies a reception signal from the power line and transmits the signal to the transmission / reception unit, and is provided with switch means at the input terminal of the reception amplifier. By bypassing the reception amplifier and inputting the transmission signal to the transmission / reception unit, the input of the transmission signal is cut off by the switch means, so that the transmission signal can be monitored and the increase in power consumption due to amplification of the signal in the reception amplifier is Absent.

  According to the power line carrier communication apparatus of claim 3, since the power supply voltage supplied to the reception amplifier is cut off, the power consumption in the reception amplifier can be completely eliminated.

  According to the power line carrier communication device of claim 4, the transmission / reception unit that outputs the transmission signal and receives the reception signal and the output end are coupled to the power line, and the transmission signal from the transmission / reception unit is amplified to the power line. A transmission amplifier for transmission, and a reception amplifier whose input terminal is coupled to the power line, amplifies the reception signal from the power line and transmits the transmission signal to the transmission / reception unit, and attenuates the transmission signal output from the transmission amplifier during transmission Therefore, the transmission signal can be monitored, and an increase in power consumption due to signal amplification in the reception amplifier can be suppressed to a small extent.

  According to the power line carrier communication device of claim 5, since the switch means is provided at the input terminal of the reception amplifier, the attenuator is connected in parallel to the switch means, and the switch means is turned off at the time of transmission. It can be input to the receiving amplifier via an attenuator.

  An embodiment of the power line carrier communication device of the present invention will be described with reference to FIGS. The power line carrier communication device in the present embodiment is a power line communication modem.

  First, in FIG. 1 showing the first embodiment, a transmission / reception unit 1 exchanges a transmission signal and a reception signal under the control of a control unit (not shown), and outputs an output end of the transmission signal, an input end of the reception signal, and a transmission / reception switching signal. Output terminal. The transmission signal output from the transmission / reception unit 1 is amplified by the transmission amplifier 2 and transmitted to the power line 5 through the band pass filter 3 and the insulating transformer 4. The transmission amplifier 2 includes, for example, two stages of balanced amplifier circuits 2 a and 2 b, and the output ends thereof are connected to the band pass filter 3. The second-stage amplifier circuit 2b is controlled via the switching circuit 6 by the switching signal SW from the transmission / reception unit 1 so as to operate at the time of transmission.

  A reception signal transmitted via the power line 5 is amplified by the reception amplifier 7 and input to the transmission / reception unit 1. The reception amplifier 7 includes, for example, two-stage amplifier circuits 7 a and 7 b and a band pass filter 7 c, and an input end thereof is connected to the band pass filter 3. Therefore, the output terminal of the transmission amplifier 2 and the input terminal of the reception amplifier 7 are connected to each other. The first stage amplifier circuit 7a has balanced input and unbalanced output.

Here, the output terminal of the first-stage amplifier circuit 2 a in the transmission amplifier 2 and the input terminal of the band-pass filter 7 c in the reception amplifier 7 are coupled by the bypass transformer 8. Therefore, the transformer 8 has a balanced input and an unbalanced output.
The power supply voltage is supplied to the amplifier circuits 7 a and 7 b of the reception amplifier 7 through the switch means 9. The switch means 9 is controlled by the switching circuit 6.

  In the above configuration, when receiving a signal from a communication partner, the signal is input to the reception amplifier 7 via the isolation transformer 4 and the band pass filter 3. At this time, the switching signal SW output from the transmission / reception unit 1 is input to the switch means 9 via the switching circuit 6 to the amplifier circuits 7a and 7b, which is turned on, and the power supply voltage is supplied. The reception signal amplified by the reception amplifier 7 is input to the transmission / reception unit 1. The operation of the second-stage amplifier circuit 2 b of the transmission amplifier 2 is stopped by the switching circuit 6.

At the time of transmission, first, the second-stage amplifier circuit 2 b in the transmission amplifier 2 is put into an operation state by the switching circuit 6. Then, a transmission signal from the transmission / reception unit 1 is transmitted to the power line 5 via the transmission amplifier 2, the band pass filter 3, and the insulation transformer 4. At this time,
Since the switch circuit 9 is turned off by the switching circuit 6 to the two amplifier circuits 7a and 7b in the reception amplifier 7, the supply of the power supply voltage is stopped. The transmission signal output from the first-stage amplifier circuit 2 a is input to the final-stage bandpass filter 7 c in the reception amplifier 7 through the transformer 8. That is, the transmission signal is fed back to the transmission / reception unit 1 by bypassing the amplifier circuits 7a and 7b. As a result, transmission signals can be monitored and power consumption in the reception amplifier 7 can be avoided.

  FIG. 2 shows the configuration of the second embodiment. In this embodiment, the bypass transformer 8 is provided in the same manner as in FIG. 1, but the switch means 10 is provided on the input side of the reception amplifier 7. The switch means 10 is controlled by the switching circuit 6 and is turned on at the time of reception and turned off at the time of transmission. Therefore, the transmission signal output from the transmission amplifier 2 is not input to the reception amplifier 7 during transmission. Therefore, even when the power supply voltage is supplied to the amplifier circuits 7a and 7b of the reception amplifier 7, only the power consumption in the steady state is obtained, and there is no increase in power consumption due to signal amplification. At this time, similarly to the configuration of FIG. 1, if the supply of the power supply voltage to the amplifier circuits 7a and 7b is stopped, the current consumption can be further reduced.

  FIG. 3 shows the configuration of the third embodiment. This embodiment differs from the configuration of FIG. 2 in that an attenuator 11 is connected in parallel to the switch means 10 instead of deleting the bypass transformer 8. Similar to the configuration of FIG. 2, the switch means 10 is turned on at the time of reception and turned off at the time of transmission. Accordingly, at the time of transmission, the transmission signal output from the transmission amplifier 2 is input to the reception amplifier 7 via the attenuator 11. However, since the level of the transmission signal input to the reception amplifier 7 is suppressed, an increase in current due to the operation of the reception amplifier 7 is small. Therefore, power consumption can be reduced. In this embodiment, it is necessary to supply power to the reception amplifier 7 unlike FIG.

It is a circuit diagram which shows the structure of 1st embodiment in the power line carrier communication apparatus of this invention. It is a circuit diagram which shows the structure of 2nd embodiment in the power line carrier communication apparatus of this invention. It is a circuit diagram which shows the structure of 3rd embodiment in the power line carrier communication apparatus of this invention. It is a circuit diagram which shows the structure of the conventional power line carrier communication apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1: Transmission / reception part 2: Transmission amplifier 2a, 2b: Amplifier circuit 3: Band pass filter 4: Insulation transformer 5: Power line 6: Switching circuit 7: Reception amplifier 7a, 7b: Amplifier circuit 7c: Band pass filter 8: Transformer for bypass 9, 10: Switch means 11: Attenuator

Claims (5)

A transmission / reception unit that outputs a transmission signal and receives a reception signal; an output end coupled to a power line; a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends it to the power line; and an input end connected to the power line And a reception amplifier that amplifies a reception signal from the power line and sends the transmission signal to the transmission / reception unit, and at the time of transmission, bypasses the reception amplifier and inputs the transmission signal to the transmission / reception unit, A power line carrier communication device characterized in that a power supply voltage supplied to a receiving amplifier is cut off. A transmission / reception unit that outputs a transmission signal and receives a reception signal; an output end coupled to a power line; a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends it to the power line; and an input end connected to the power line And a receiving amplifier that amplifies a received signal from the power line and sends the amplified signal to the transmission / reception unit, provided with a switch means at an input end of the receiving amplifier, and bypasses the receiving amplifier during transmission A power line carrier communication device, wherein a transmission signal is input to the transmission / reception unit, and the input of the transmission signal is blocked by the switch means. The power line carrier communication device according to claim 2, wherein a power supply voltage supplied to the reception amplifier is cut off. A transmission / reception unit that outputs a transmission signal and receives a reception signal; an output end coupled to a power line; a transmission amplifier that amplifies the transmission signal from the transmission / reception unit and sends it to the power line; and an input end connected to the power line And a reception amplifier that amplifies a reception signal from the power line and transmits the amplified signal to the transmission / reception unit, and transmits the transmission signal output from the transmission amplifier to the reception amplifier via an attenuator during transmission. A power line carrier communicator characterized by input. 5. The power line carrier communicator according to claim 4, wherein switch means is provided at an input terminal of the reception amplifier, the attenuator is connected in parallel to the switch means, and the switch means is turned off at the time of transmission. .

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