JPS6423630A - Demodulator for satellite communication - Google Patents

Demodulator for satellite communication

Info

Publication number
JPS6423630A
JPS6423630A JP17949387A JP17949387A JPS6423630A JP S6423630 A JPS6423630 A JP S6423630A JP 17949387 A JP17949387 A JP 17949387A JP 17949387 A JP17949387 A JP 17949387A JP S6423630 A JPS6423630 A JP S6423630A
Authority
JP
Japan
Prior art keywords
frequency
sweeping
circuit
locking
vco
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
JP17949387A
Other languages
Japanese (ja)
Inventor
Hideto Furukawa
Yoshiharu Tozawa
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.)
Fujitsu Ltd
Original Assignee
Fujitsu 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 Fujitsu Ltd filed Critical Fujitsu Ltd
Priority to JP17949387A priority Critical patent/JPS6423630A/en
Publication of JPS6423630A publication Critical patent/JPS6423630A/en
Pending legal-status Critical Current

Links

Abstract

PURPOSE:To make time required for re-locking a sub-synchronous carrier reproducing circuit shorter when the locking of the circuit is stepped-out, by causing sweeping by means of a sweeping circuit to be started after the sweeping starting point is set at the minimum or maximum frequency of a voltage-controlled oscillator (VCO) by resetting the counter of the sweeping circuit only. CONSTITUTION:When the carrier frequency changes from fc to fc' due to the relative movement of a geostationary satellite and the locking state is stepped- out, a counter 71 starts counting after it is reset and the sweeping by means of a sweeping circuit 7 is started from a frequency fVMIN in the vicinity of the minimum frequency fVMIN or a frequency fVMAX in the vicinity of the maximum frequency fVMAX of a voltage controlled oscillator (VCO) 8 as shown by the solid line or chain line. Then the sweeping is carried out in the direction, in which the frequency of the VCO 8 is successively raised or lowered. Therefore, the locking frequency fc can be searched in a short period.
JP17949387A 1987-07-17 1987-07-17 Demodulator for satellite communication Pending JPS6423630A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17949387A JPS6423630A (en) 1987-07-17 1987-07-17 Demodulator for satellite communication

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17949387A JPS6423630A (en) 1987-07-17 1987-07-17 Demodulator for satellite communication

Publications (1)

Publication Number Publication Date
JPS6423630A true JPS6423630A (en) 1989-01-26

Family

ID=16066788

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17949387A Pending JPS6423630A (en) 1987-07-17 1987-07-17 Demodulator for satellite communication

Country Status (1)

Country Link
JP (1) JPS6423630A (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05191216A (en) * 1992-01-10 1993-07-30 Nec Corp Sweep range control system
JPH05211424A (en) * 1992-01-30 1993-08-20 Nec Corp Frequency sweep range controller
JP2006284539A (en) * 2005-04-05 2006-10-19 Teraoka Seiko Co Ltd Load cell and balance

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05191216A (en) * 1992-01-10 1993-07-30 Nec Corp Sweep range control system
JPH05211424A (en) * 1992-01-30 1993-08-20 Nec Corp Frequency sweep range controller
JP2006284539A (en) * 2005-04-05 2006-10-19 Teraoka Seiko Co Ltd Load cell and balance

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SHAKHTARIN et al. Signal locking by a phase-locked AFC system in the frequency-search mode(Signal frequency capture probability vs frequency search rates and AFC loop parameters determined in phase locked oscillator)