Title:
AFC CONTROL METHOD
Document Type and Number:
Japanese Patent JP3541643
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To transit a control value of an AFC loop to a normal point in the case that the AFC loop is made stable at a deviated point due to the effect of a reflection wave when an input signal with the reflection wave superimposed thereon is given to a QPSK demodulation system.
SOLUTION: An AFC control range of a digital value in 8-bit expressed by the 2's complement is divided and the divided ranges are used for an AFC control variable and the AFC loop is controlled from a positive direction and a negative direction without fail, then the AFC loop that is set stably to a deviated point due to the effect of the reflection wave or the like where the frequency error component is not zero is transited to the point that is set substantially normally.
Inventors:
Katsuhiro Hamada
Kei Hasegawa
Ken Aruga
Kei Hasegawa
Ken Aruga
Application Number:
JP27838597A
Publication Date:
July 14, 2004
Filing Date:
October 13, 1997
Export Citation:
Assignee:
Matsushita Electric Industrial Co., Ltd
International Classes:
H04L27/227; (IPC1-7): H04L27/227
Domestic Patent References:
| JP3244247A | ||||
| JP4170238A |
Attorney, Agent or Firm:
Fumio Iwahashi
Tomoyasu Sakaguchi
Hiroki Naito
Tomoyasu Sakaguchi
Hiroki Naito