Patent ID: 8948306
Filing Date: 2015-02-03
Classification: H03F,H04L

Abstract:
1. A system for generating a modulated radio frequency (RF) output signal representing an analog baseband input signal, the system comprising: a digitizer configured to sample the analog baseband input signal and produce an N-bit digital signal representing a scaled linear function of the signal amplitude, where N is an integer greater than one, the digitizer utilizing an analog-to-digital amplitude converter with equal input voltage steps to provide the N-bit digital signal as a series of multi-bit binary word values, with each multi-bit binary word value varying in proportion to the instantaneous amplitude of the input signal at respective sampling times; an RF signal source configured to produce an RF carrier signal; N amplifier paths, each comprising at least one amplifier configured to receive the RF carrier signal as an input and provide a corresponding output RF signal, the amplifiers associated with each of the N amplifier paths being active only when a corresponding bit of the digital signal assumes a first value and each of the N amplifier paths providing a maximum voltage out that is different from each other of the N amplifier paths; and a power combiner assembly configured to combine the outputs of the plurality of amplifier paths to deliver the modulated RF output signal.