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:
Apr. 02, 2013
Filed:
Jun. 03, 2008
Hosei Matsuoka, Yokosuka, JP;
Takeshi Yoshimura, Yokohama, JP;
Toshirou Kawahara, Yokohama, JP;
NTT DoCoMo, Inc., Tokyo, JP;
Abstract
A modulation device, a demodulation device, and a transmission system and acoustic signal transmission method using them which can carry out a synchronization process for data signals without using a carrier frequency for a synchronization signal. The modulation device transmits an acoustic signal superposed with a PN sequence set according to a carrier frequency and a data signal. A demodulation device receives the acoustic signal, determines the PN sequence having the highest maximum correlation value with the acoustic signal in a plurality of PN sequences, detects a symbol synchronization point according to the correlation value between the thus determined PN sequence and the acoustic signal, and performs a synchronization process. Thereafter, according to the detected synchronization point and determined PN sequence, an OFDM demodulation processing unit decides the carrier frequency band of the data signal superposed on the acoustic signal and demodulates the data signal.