Patent ID: 6826237
Filing Date: 2004-11-30
Classification: H03D,H04L

Abstract:
A radio transmitter comprising modulation means for producing quadrature modulated signals, first frequency-translation means for translating said signals to a variable intermediate frequency (IF) signal in digital form in an IF frequency band, digital to analogue conversion means for converting said variable IF signal to analogue form, second frequency-translation means for translating said analogue IF signal by a fixed frequency to a radio frequency (RF) signal, said fixed frequency being provided by a fixed frequency voltage controlled oscillator (VCO) source, reference oscillator means having an output, power amplifying means for amplifying said RF signal to form an amplified signal, and signal propagation means for propagating said amplified signal, wherein said first frequency-translation means includes a digital up-converter configured to receive signals from an IF synthesizer, and wherein said output of said reference oscillator means is connected to said IF synthesizer and said fixed frequency VCO.