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:
Mar. 09, 1999
Filed:
Dec. 31, 1996
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
In a transmitting unit, an input signal is converted into an I data sequence of an in-phase (I) symbol and a Q data sequence of a quadrature (Q) symbol, a differential encoding is performed for the I and Q data sequences according to a differential binary phase shift keying (DBPSK) modulation to produce an I code sequence and a Q code sequence, a spectrum of the I code sequence is spread by a first spreading code signal to produce an I spread spectrum signal, a spectrum of the Q code sequence is spread by a second spreading code signal to produce a Q spread spectrum signal, the I and Q spread spectrum signals are quadrature-modulated to a synthesized signal, and the synthesized signal is transmitted to a receiving unit. In the receiving unit, the synthesized signal is quadrature-demodulated to a first baseband signal and a second baseband signal, the first and second baseband signals are respectively correlated with each of the first and second spreading code signals to obtain first and second I correlated signals and first and second Q correlated signals, and a BPSK delay detection is performed for a group of the first and second I correlated signals and a group of the first and second Q correlated signals to reproduce the I and Q data sequences.