Demodulators – Phase shift keying or quadrature amplitude demodulator – Input signal combined with local oscillator or carrier...
Patent
1993-01-28
1994-12-13
Mis, David
Demodulators
Phase shift keying or quadrature amplitude demodulator
Input signal combined with local oscillator or carrier...
329308, 329309, 329310, 375 81, 375 82, 375 85, H03C 300, H03D 300, H03D 320, H04L 2714
Patent
active
053732472
ABSTRACT:
An AFC method is used in a demodulator, which employs a 2.sup.n -phase phase shift keying modulation system, where n is an integer greater than or equal to two, to correct an error between a received carrier frequency and a local frequency. The AFC method includes the steps of (a) subjecting an intermediate frequency signal of a signal received by the demodulator to a quadrature wave detection to obtain I-axis and Q-axis signals, (b) converting amplitude information of the I-axis and Q-axis signals into phase information which includes frequency information, and (c) correcting the local frequency based on the frequency information included in the phase information.
REFERENCES:
patent: 4238739 (1980-12-01), Mosley et al.
patent: 4250456 (1981-02-01), Shinmyo et al.
patent: 4470145 (1984-09-01), Williams
patent: 5068876 (1991-11-01), Yoshikawa et al.
patent: 5260671 (1993-11-01), Iso et al.
patent: 5282227 (1994-01-01), Crawford
Furukawa Hideto
Matsuyama Koji
Sato Tomonori
Fujitsu Limited
Mis David
LandOfFree
Automatic frequency control method and circuit for correcting an does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic frequency control method and circuit for correcting an, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic frequency control method and circuit for correcting an will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1195645