Patent ID: 7570707
Filing Date: 2009-08-04
Classification: H03C,H03F,H04L

Abstract:
1. An RF transmitter, comprising: digital processor for producing outgoing digital IF signals comprising an envelope magnitude component and a phase component wherein the envelope magnitude component is produced on an envelope signal path and wherein the phase component is produced on a phase signal path, wherein the digital processor further includes a time shift block in at least one of the envelope and phase signal paths, wherein the time shift block implements a cubic polynomial that generates a time shift based upon a plurality of sequential sampled values of the outgoing digital IF signals to one of the envelope magnitude and phase components, the time shift block including: first and second digital to analog converters (DACs) on the envelope and phase signal paths coupled to receive the envelope magnitude and phase components, respectively, the first and second DACs producing outgoing analog envelope and phase components; first and second low pass filters for producing filtered outgoing magnitude and phase components, respectively, based upon the outgoing magnitude and phase components; translational loop for up-converting the filtered outgoing phase component from IF to RF to produce an outgoing RF phase component; and power amplifier that produces outgoing RF based upon the outgoing RF phase component having an outgoing power level based upon the filtered outgoing magnitude component.