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. 27, 1982
Filed:
Dec. 12, 1979
Paul W Baier, Kaiserslautern, DE;
Klaus Dostert, Kaiserslautern, DE;
Madhukar Pandit, Kaiserslautern, DE;
Reinhard Simons, Kaiserslautern, DE;
Siemens Aktiengesellschaft, Berlin & Munich, DE;
Abstract
A receiving circuit for an interference-suppressing communications system having a narrow-band conventional message modulation and additional pseudo-noise phase shift keying (PN-PSK), has a pseudo-random generator whose pseudo-random sequence is identical to the pseudo-random sequence provided by the system transmitter. The pseudo-random generator actuates a phase-shift keying element to cancel the phase shift modulation produced at the transmitter. A matched filter or correlation network for correlation of the pseudo-random sequence at the receiver with the pseudo-random sequence contained in the received signal is provided. The message modulation impairs the function of the matched filter or the correlation network. The degrading influence of message modulation is to be eliminated, at least, reduced. To this end, a demodulation circuit is provided which receives the entire received signal and the signal present after removal of the phase-shift keying to provide an input for the matched filter or correlation network. This signal only exhibits the pseudo-noise phase-shift keying contained in the received signal, but no longer has the message modulation.