The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 03, 2011
Filed:
Feb. 16, 2005
Shunji Kimura, Chiba, JP;
Tomoaki Yoshida, Chiba, JP;
Koji Kitahara, Zama, JP;
Hiroshi Takada, Mito, JP;
Shunji Kimura, Chiba, JP;
Tomoaki Yoshida, Chiba, JP;
Koji Kitahara, Zama, JP;
Hiroshi Takada, Mito, JP;
Nippon Telegraph and Telephone Corporation, Tokyo, JP;
NTT Electronics Corporation, Tokyo, JP;
Abstract
A bit-rate automatic control circuit for feedback controlling the gain and bandwidth of a preamplifier in dependence on the bit-rate of a signal is disclosed. The circuit includes a bit-rate discrimination circuit configured to discriminate the bit rate of the signal, and an alarm circuit configured to determine whether the value of received power of the signal is less than the minimum acceptable value of the preamplifier or not. If said alarm circuit determines that the value of received power of the signal is less than the minimum acceptable value of the preamplifier, the bit-rate automatic control circuit determines, irrespective of the discrimination of said bit-rate discrimination circuit, that the bit-rate of the signal is low, and feedback controls the preamplifier based on the determination. According to the above arrangements, if a determination is made that the reception level of the input signal is lower than the minimum acceptable value of received power, the preamplifier can be switched from a state for receiving a high bit-rate signal to a state for receiving a low bit-rate signal.