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. 26, 1989
Filed:
Mar. 10, 1988
Timothy H Pearce, Springfield, GB;
The General Electric Company, p.l.c., London, GB;
Abstract
An analogue-to-digital converter in accordance with the invention comprises a feed-forward arrangement in which, in a first stage, the analogue input signal is applied via a filter to a subtractor along a first path and is applied via a second path to an analogue-to-digital converter followed by a digital filter and then converted back into analogue form to be applied via a bandpass filter to the subtractor. The output of the subtractor is therefore an error signal representative of the difference between the analogue input signal and the predicted signal in analogue form. The error signal is applied to an analogue-to-digital converter and is combined with the predicted signal in digital form taken from the output of the digital filter via another filter to produce the digital output signal. Control means are provided to provide phase and gain matching between different parts of the circuit. The digital filter is such that its output noise spectrum is arranged to be shaped so as to include a null around the quarter sampling frequency, enabling the following D-A converter to be of low resolution.