A method for applying spread spectrum noise reduction techniques to USB specifically USB2.0 communications systems includes the step of generating a base (seed) frequency for the USB system, modulating the base (seed) frequency with a spread spectrum (SS) characteristic, and utilizing (as-is, not modified)...http://www.google.com.hk/patents/US7953175?utm_source=gb-gplus-share專利 US7953175 - USB system with spread spectrum EMI reduction
