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. 07, 1993
Filed:
Jun. 24, 1992
Richard C Edwards, Cedar Rapids, IA (US);
Rockwell International Corporation, Seal Beach, CA (US);
Abstract
A digital amplitude modulator receives a plurality of phase coherent input signals from a plurality of amplifiers (A1-An) respectively representing the bits of a plural bit digital word and converts them to a single output signal on an output with a first plurality of transformers having transformer ratios which vary substantially in accordance with a power of two corresponding to the significance of the bit represented by the input signal being converted thereby and a second plurality of transformers having primaries connected to the first plurality of transformers, respectively, and secondaries all connected in series together to an output terminal and transformer ratios which vary in substantial accordance with the same powers of two that the transformer ratio of the first plurality of transformers to which they are connected vary. In one embodiment the second group of transformers are transmission line element transformers with electrical lengths equal to one quarter wavelength, while in another embodiment element coil transformers are employed.