05736893 is referenced by 18 patents and cites 10 patents.

A clock reference frequency is digitally derived from a base signal, then digitally modulated by ramping the clock reference frequency up and down about a desired frequency. The modulation occurs in periodic fashion at a prescribed modulation frequency. Such modulation spreads the electromagnetic energy of the system signals over a band that is a portion of the desired clock frequency. As a result, energy in harmonics of the respective system signals also are spread. When the energy spreading of any system signal or harmonic of such signal occurs over a bandwidth greater than the 120 kHz bandwidth of conventional communication receivers, adverse EMI emissions are reduced.

Title
Digital method and apparatus for reducing EMI emissions in digitally-clocked systems
Application Number
8/592975
Publication Number
5736893
Application Date
January 29, 1996
Publication Date
April 7, 1998
Inventor
Preston D Brown
Eugene
OR, US
Robert B E Puckette
Corvallis
OR, US
Assignee
Hewlett Packard Company
CA, US
IPC
H03B 29/00
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