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. 15, 1988
Filed:
Oct. 03, 1986
Applicant:
Inventors:
David M Motley, Santa Ana, CA (US);
John F Stockman, Costa Mesa, CA (US);
Assignee:
Hycom Incorporated, Irvine, CA (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04B / ; H04L / ;
U.S. Cl.
CPC ...
375 58 ; 375101 ; 375103 ; 375 60 ;
Abstract
Filter quality is substantially improved (or complexity substantially reduced) in a digital PSK modem requiring an overall filter characteristic of the percent raised cosine type by using, in both the transmitter and the receiver, a filter having the same percent raised cosine response but at a higher cutoff frequency which satisfies the formula ##EQU1## where f.sub.f is the cutoff frequency (6 db) of the new filter, f.sub.o is one-half the baud rate of the modem, and .alpha. is the percent raised cosine expressed in decimal form.