Patent ID: 8981980
Filing Date: 2015-03-17
Classification: H03F,H03M,H04B,H04L

Abstract:
1. A method, comprising: receiving a first stream of samples to a sample input of a first digital to analog converter (DAC) for setting an output level at an output of the first DAC based upon a value of the samples and at a time indicated by a first sample clock signal having a sample frequency, fs, applied to a clock input of the first DAC; applying the first sample clock signal to a local oscillator (LO) input of a first up-converter and receiving an output signal from the output of the first DAC at a signal input of the first up-converter; receiving a second stream of samples to a sample input of a second DAC, the second stream of samples having a sample time coincident with the timing of a second sample clock signal applied to a clock input of the second DAC, the second sample clock signal having the same sample frequency as the first sample clock signal and a quadrature offset in time from the first sample clock signal; applying the second sample clock signal to an LO input of a second up-converter and receiving an output signal from an output of the second DAC at a signal input of the second up-converter; and summing an output of the first up-converter and an output of the second up-converter to generate a radio frequency (RF) output signal in which at least one of a lower sideband (LSB), an upper sideband (USB), and one or more spectral images are suppressed.