Signal generation using single-bit sigma-delta techniques

In this paper, we present a digital oscillator, based on the single-bit (Sigma) (Delta) modulation principle. With the exception of a front end analog filter, the proposed circuit is entirely digital. The oscillator is achieved by the use of a (Sigma)(delta) modulator in the digital resonator loop. A novel topology for constructing stable high-order 1-bit modulators is described. A fourth-order low-pass and eighth-order bandpass oscillators are implemented in field-programmable gate array prototype. The experimental results demonstrate stability and feasibility, achieving more than 110-dB dynamic range for the generated signals.