JPS6442928A - Two-wire type full duplex modem with echo canceller - Google Patents

Two-wire type full duplex modem with echo canceller

Info

Publication number
JPS6442928A
JPS6442928A JP19814687A JP19814687A JPS6442928A JP S6442928 A JPS6442928 A JP S6442928A JP 19814687 A JP19814687 A JP 19814687A JP 19814687 A JP19814687 A JP 19814687A JP S6442928 A JPS6442928 A JP S6442928A
Authority
JP
Japan
Prior art keywords
power
deciding
circuit
echo canceller
signal
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
JP19814687A
Other languages
Japanese (ja)
Inventor
Mitsuharu Yano
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
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 filed Critical NEC Corp
Priority to JP19814687A priority Critical patent/JPS6442928A/en
Publication of JPS6442928A publication Critical patent/JPS6442928A/en
Pending legal-status Critical Current

Links

Landscapes

  • Bidirectional Digital Transmission (AREA)
  • Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)

Abstract

PURPOSE:To surely decide double talk state by increasing or decreasing sequentially the power of a transmission signal by an output of a monitoring circuit monitoring whether or not a power level of an error signal obtained from a deciding circuit deciding the reception data is a certain level or above. CONSTITUTION:A monitoring circuit 7 outputs a signal when a power level of an error signal obtained from a deciding circuit 6 deciding a reception data and supplies it to a power control circuit 2 as a control signal. The power control circuit 2 gives a difference to correct the difference of the loss conversely even when the loss of the subscriber line at the outgoing side and the incoming side differs between the power of the transmission signals of two sets of MODEMs at the outgoing side and incoming side, thereby increasing or decreasing the power of transmission signal sequentially. Thus, even when a network echo canceller 4 does not have a reception function of a disable tone, the decision of double talk state is ensured.
JP19814687A 1987-08-10 1987-08-10 Two-wire type full duplex modem with echo canceller Pending JPS6442928A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP19814687A JPS6442928A (en) 1987-08-10 1987-08-10 Two-wire type full duplex modem with echo canceller

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP19814687A JPS6442928A (en) 1987-08-10 1987-08-10 Two-wire type full duplex modem with echo canceller

Publications (1)

Publication Number Publication Date
JPS6442928A true JPS6442928A (en) 1989-02-15

Family

ID=16386227

Family Applications (1)

Application Number Title Priority Date Filing Date
JP19814687A Pending JPS6442928A (en) 1987-08-10 1987-08-10 Two-wire type full duplex modem with echo canceller

Country Status (1)

Country Link
JP (1) JPS6442928A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0399571A (en) * 1989-09-12 1991-04-24 Aiwa Co Ltd Transmission level adjusting method for terminal equipment

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH0399571A (en) * 1989-09-12 1991-04-24 Aiwa Co Ltd Transmission level adjusting method for terminal equipment

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