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:
Jun. 25, 2002
Filed:
Aug. 25, 1998
Sony Corporation, Tokyo, JP;
Abstract
A correlation detecting apparatus is capable of securely detecting a M sequence code forming a reference for timing even when a plurality of signals with different amplitudes are time division multiplexed includes matched filter ( ) for detecting a predetermined code from a received signal, an average amplitude detector circuit ( ) for detecting an average amplitude of the received signal, and a divider circuit ( ) for normalizing an output of the matched filter ( ) by an output of the average amplitude detector circuit 83 are provided. The output of the matched filter ( ) normalized by the divider circuit ( ) is compared with a threshold value for outputting a correlation detecting signal. When a received signal level is large, the output level of the matched filter ( ) becomes large. However, in this case because the average amplitude of the received signal also becomes large, a divided value of the output level of the matched filter ( ) by the output level of the average amplitude detector circuit ( ) makes almost no change. In contrast to this, the output level of the matched filter when an M sequence is received remains nearly constant irrespective of an input signal level. Therefore, the received signal of M sequence can be detected without fail from the output of the comparator circuit ( ).