Patent ID: 6546061
Filing Date: 2003-04-08
Classification: H03H,H04J,H04L

Abstract:
A signal transformation method, comprising the steps of:modulating at least a set of complex digital baseband signals; up-sampling the set of complex digital baseband signals, each having an I component and a Q component, to form a set of complex digital high-frequency signals, each having a corresponding I component and a Q component; forming a set of real digital narrowband high-frequency signals by filtering said set of complex high-frequency signals through a corresponding set of complex digital bandpass filters having substantially non-overlapping narrow passbands; combining said real narrowband high-frequency signals to form a real digital wideband high-frequency signal; and D/A converting the real digital wideband high-frequency bandpass signal into a real analog wideband high-frequency bandpass signal.