JPS5570145A - Adaptive dpcm system - Google Patents

Adaptive dpcm system

Info

Publication number
JPS5570145A
JPS5570145A JP14397778A JP14397778A JPS5570145A JP S5570145 A JPS5570145 A JP S5570145A JP 14397778 A JP14397778 A JP 14397778A JP 14397778 A JP14397778 A JP 14397778A JP S5570145 A JPS5570145 A JP S5570145A
Authority
JP
Japan
Prior art keywords
adaptive
quantizer
effect
predicting unit
transmission code
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
JP14397778A
Other languages
Japanese (ja)
Inventor
Kazunori Ozawa
Taku Arazeki
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric 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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP14397778A priority Critical patent/JPS5570145A/en
Publication of JPS5570145A publication Critical patent/JPS5570145A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B14/00—Transmission systems not characterised by the medium used for transmission
    • H04B14/02—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation
    • H04B14/06—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation using differential modulation, e.g. delta modulation
    • H04B14/066—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation using differential modulation, e.g. delta modulation using differential modulation with several bits [NDPCM]
    • H04B14/068—Transmission systems not characterised by the medium used for transmission characterised by the use of pulse modulation using differential modulation, e.g. delta modulation using differential modulation with several bits [NDPCM] with adaptive feedback

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Transmission Systems Not Characterized By The Medium Used For Transmission (AREA)

Abstract

PURPOSE:To secure a quick recovery for the effect of the error of the transmission code through a simple device constitution by securing the recovery from the effect of the transmission code error with every frame time and via the backward-type adaptive predicting unit to perform the adaptive primary prediction. CONSTITUTION:Input signal Xj sent from terminal 105 is applied to subtractor 110, and the subtraction is given to the output of adaptive predicting unit 150 to deliver residual ej. Then residual ej is quantized at adaptive quantizer 120 to the prescribed sampling time to deliver quantization level lj. The level lj is applied to adaptive reverse quantizer 130 featuring the reverse characteristics to encoder 180 and quantizer 120, and output code qj of encoder 180 is transmitted to the reception side via multiplexer 190. Here backward-type quantization step size correction circuit 170 is provided at the transmission side, and the prediction coefficient value of one unit is set to the prescribed value. And the frame synchronous signal is combined with the quantized value. Then adaptive predicting unit 270, adaptive reverse quantizer 240, etc. are installed at the reception side, thus ensuring a quick recovery from the effect of the transmission code error.
JP14397778A 1978-11-21 1978-11-21 Adaptive dpcm system Pending JPS5570145A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP14397778A JPS5570145A (en) 1978-11-21 1978-11-21 Adaptive dpcm system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP14397778A JPS5570145A (en) 1978-11-21 1978-11-21 Adaptive dpcm system

Publications (1)

Publication Number Publication Date
JPS5570145A true JPS5570145A (en) 1980-05-27

Family

ID=15351439

Family Applications (1)

Application Number Title Priority Date Filing Date
JP14397778A Pending JPS5570145A (en) 1978-11-21 1978-11-21 Adaptive dpcm system

Country Status (1)

Country Link
JP (1) JPS5570145A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1985005747A1 (en) * 1984-05-28 1985-12-19 Sony Corporation Digital signal transmission device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1985005747A1 (en) * 1984-05-28 1985-12-19 Sony Corporation Digital signal transmission device

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