JPS6489830A - Modem communication system with primary and secondary channels - Google Patents

Modem communication system with primary and secondary channels

Info

Publication number
JPS6489830A
JPS6489830A JP22260888A JP22260888A JPS6489830A JP S6489830 A JPS6489830 A JP S6489830A JP 22260888 A JP22260888 A JP 22260888A JP 22260888 A JP22260888 A JP 22260888A JP S6489830 A JPS6489830 A JP S6489830A
Authority
JP
Japan
Prior art keywords
receiver
secondary channels
primary
main channel
communication system
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.)
Granted
Application number
JP22260888A
Other languages
Japanese (ja)
Other versions
JP2747562B2 (en
Inventor
Kamaaman Aadoriaan
Piitorasu Noobaatasu Yohaanesu
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.)
NCR Voyix Corp
Original Assignee
NCR 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
Priority claimed from GB8721260A external-priority patent/GB2209648B/en
Application filed by NCR Corp filed Critical NCR Corp
Publication of JPS6489830A publication Critical patent/JPS6489830A/en
Application granted granted Critical
Publication of JP2747562B2 publication Critical patent/JP2747562B2/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Abstract

PURPOSE: To attain high main channel signal suppression with the minimum circuitry in a digital signal processing by using a low-pass filter, and sharing an analog/digital converter by main and secondary channels. CONSTITUTION: A receiving line 24 is connected to an analog/digital converter 54 of the transmitter/receiver of a control MODEM, and the output is connected through a notch filter 58 to a main channel receiver 60 and also to a secondary channel receiver 62. The secondary channel receiver 62 is provided with low-pass IIR digital filters 110A, 110B, and 110C. Thus, the exact filtering and high suppression of a main channel signal frequency can be attained without causing any frequency hold-over.
JP22260888A 1987-09-10 1988-09-07 Modem communication system with primary and secondary channels Expired - Fee Related JP2747562B2 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
GB8721260A GB2209648B (en) 1987-09-10 1987-09-10 Modem communication system having main and secondary channels
US8721260 1988-03-30
US07/175,375 US4860308A (en) 1987-09-10 1988-03-30 Modem communication system having main and secondary channels
US175,375 1988-03-30

Publications (2)

Publication Number Publication Date
JPS6489830A true JPS6489830A (en) 1989-04-05
JP2747562B2 JP2747562B2 (en) 1998-05-06

Family

ID=26292707

Family Applications (1)

Application Number Title Priority Date Filing Date
JP22260888A Expired - Fee Related JP2747562B2 (en) 1987-09-10 1988-09-07 Modem communication system with primary and secondary channels

Country Status (1)

Country Link
JP (1) JP2747562B2 (en)

Also Published As

Publication number Publication date
JP2747562B2 (en) 1998-05-06

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Legal Events

Date Code Title Description
LAPS Cancellation because of no payment of annual fees