The following operators can be used to better focus your queries.
( ) , AND, OR, NOT, W/#
? single char wildcard, not at start
* multi char wildcard, not at start
(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*
This guide provides a more detailed description of the syntax that is supported along with examples.
This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.
Concept Search - What can I type?
For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.
Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.
Illustrated is an active technique for cancelling common-mode and differential-mode noise conducted on power lines and communication cables.
English (United States)
This text was extracted from a PDF file.
At least one non-text object (such as an image or picture) has been suppressed.
This is the abbreviated version, containing approximately
54% of the total text.
Page 1 of 3
Conducted Noise Cancellation
Illustrated is an active technique for cancelling common-mode and
differential-mode noise conducted on power lines and communication cables.
Electromagnetic noise generated by electrical and electronic equipment can
escape by propagating on power cables and communication lines which attach to
the equipment. This conducted noise is a potential source of interference to
communications and other equipment.
This technique allows conducted noise to be cancelled. Fig. 1 shows the
general set-up for cancelling common-mode noise on a communication cable or
power cord. Fig. 2 shows the wire arrangement for cancelling differential-mode
noise on a two-wire power cord or communication line.
The noise is generated in the product 1 by source V/N/ which has impedance
Z/1/. The noise propagates along the cable 2 and results in a load voltage V/L/
and load current I/L/ in load Z/2/.
A pick-up current probe 3 samples the noise current flowing on the cable.
The output of this current probe is fed to an amplifier 4 which has adjustable
gain. The output of the amplifier passes through an RF filter 5 and drives an
injection current probe 6 which induces a voltage on the cable equal in
magnitude and opposite in phase to V/N/, thus reducing the load voltage V/L/ and
For broadband operation, that is, for simultaneously cancelling noise over a
wide portion of the spectrum, distances d1 and d2 should be much less than the
wavelength of the highest frequency. A...