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:
Aug. 02, 1977
Filed:
Oct. 01, 1975
Oke A Fredriksson, Fullerton, CA (US);
Elmer L Thomas, Fullerton, CA (US);
Chevron Research Company, San Francisco, CA (US);
Abstract
This disclosure relates to a non-recursive digital synthesizer for producing a surprisingly accurate synthesized sinusoid suitable for testing elements of a geophysical data acquisition system in either a laboratory or a field environment. In accordance with the present invention, [(C/2)+1]-discrete--16-bit binary words are stored in a read-only memory (ROM), representing discrete amplitudes of a digitized sinusoid in a frequency range of 1-500 Hz, and then accessed in succession to a digital-to-analog converter (DAC). A separate suppression circuit means at the output of the DAC is adapted to operate in synchronization with movement of the binary words through the DAC; in that way, glitches generated by the various digital elements of the synthesizer are suppressed. Result: accuracy of the generated sinusoid to the elements under test is assured.