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:
Dec. 17, 1996
Filed:
Nov. 12, 1993
Applicant:
Inventors:
Seppo E Lamberg, Salo, FI;
Zhi C Honkasalo, Helsinki, FI;
Assignee:
Nokia Mobile Phones Ltd., Salo, FI;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04L / ;
U.S. Cl.
CPC ...
329304 ; 375329 ; 375330 ; 375281 ; 375283 ;
Abstract
A method is disclosed of demodulating a signal (20) modulated by differential quadrature phase shift keying so that two bits of information are coded into each symbol period. The method comprises using a high frequency clock to determine the time taken (t.sub.1, t.sub.2, t.sub.3, t.sub.4), for the modulated signal to execute a predetermined number of cycles, such as 21, in the symbol period (T) and comparing the time thereby determined with the time (t.sub.o) of execution of the predetermined number of cycles for an unmodulated signal.