JPS5595435A - Power-line carrier type interphone unit - Google Patents

Power-line carrier type interphone unit

Info

Publication number
JPS5595435A
JPS5595435A JP180679A JP180679A JPS5595435A JP S5595435 A JPS5595435 A JP S5595435A JP 180679 A JP180679 A JP 180679A JP 180679 A JP180679 A JP 180679A JP S5595435 A JPS5595435 A JP S5595435A
Authority
JP
Japan
Prior art keywords
signal
power
circuit
power line
level
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP180679A
Other languages
Japanese (ja)
Inventor
Hiroshi Kito
Hideaki Yatabe
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP180679A priority Critical patent/JPS5595435A/en
Publication of JPS5595435A publication Critical patent/JPS5595435A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B1/00—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission
    • H04B1/62—Details of transmission systems, not covered by a single one of groups H04B3/00 - H04B13/00; Details of transmission systems not characterised by the medium used for transmission for providing a predistortion of the signal in the transmitter and corresponding correction in the receiver, e.g. for improving the signal/noise ratio
    • H04B1/64—Volume compression or expansion arrangements

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To reduce noise caused by a power line by narrowing a carrier occupancy band by transmitting a signal with its amplitude compressed according to a sound signal level and then by expanding it at a reception side corresponding to the level. CONSTITUTION:Power-line carrier system interphone units I1 and I2 are connected together by power cord plugs 1 and 1' of power line (l), and transmission and reception operations are alternated by duplexers 11 and 12 to obtain transmission or reception by using microphone speaker 13. At the output side of sound signal amplifier 8 of this transmission side, signal voltage compression circuit 9 is provided which compresses the amplitude of a signal corresponding to a sound signal level, and the output of circuit 9 is applied to band-pass filter 4 via modulation circuit 10 to send the signal out to power line (l). To the output of demodulator circuit 5 of the reception side, signal voltage expander circuit 6 is provided so as to expand the signal corresponding to the level of the received signal, and consequently the carrier occupancy band of the sound signal in the carrier is narrowed to reduce effectively noises caused by power line (l).
JP180679A 1979-01-11 1979-01-11 Power-line carrier type interphone unit Pending JPS5595435A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP180679A JPS5595435A (en) 1979-01-11 1979-01-11 Power-line carrier type interphone unit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP180679A JPS5595435A (en) 1979-01-11 1979-01-11 Power-line carrier type interphone unit

Publications (1)

Publication Number Publication Date
JPS5595435A true JPS5595435A (en) 1980-07-19

Family

ID=11511809

Family Applications (1)

Application Number Title Priority Date Filing Date
JP180679A Pending JPS5595435A (en) 1979-01-11 1979-01-11 Power-line carrier type interphone unit

Country Status (1)

Country Link
JP (1) JPS5595435A (en)

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