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:
Jan. 11, 1994
Filed:
Jul. 17, 1992
Clarion Co., Ltd., Tokyo, JP;
Abstract
A spread spectrum communication device according to the present invention includes a transmitter and a receiver, and suppresses demodulation errors to a minimum value, even if there exit a plurality of narrow band disturbing signals. In the transmitter, a first PN (pseudo noise) code from a fist PN code generator and a second PN code having a delayed phase coming from a shift register are inputted to a multiplexer and switched according to an exclusive logic sum of data and a disturbing signal. The multiplexer output is modulated by a modulator so that it can be transmitted. In the receiver, a correlation output from a correlator is detected by a detector and a detection output thereof is digitalized by a voltage comparator. A correlation pulse thus obtained is applied to two AND gates. Two time window pulses are each applied to two multiplexers nd are switched by a control signal, the outputs of the multiplexers being respectively applied to these AND gates. Pulses from these AND gates are counted by an up-counter and a down-counter in a demodulating circuit to demodulate the data.