Digital Sinusoidal Recursive Oscillators with Quadrature and Three Phase Outputs

Digital oscillators are essential parts in many applications. They are used in communications, control, radar, in digital signal processing and music synthesis. Flexibility, and low cost are the main advantages of such type of oscillators. Moreover, the parameters of a digitally generated sine signal are easy to control. Nowadays a Direct Digital Synthesis oscillators (DDS) with sine look-up table are most often used as a conventional method for generating sinusoidal waveforms, but recursive digital oscillators with quadrature or three phase outputs can be also used in different applications. Because of the finite word-length and therefore quantization it can be therefore some problems with amplitude stabilization and amplitude changing. In this paper, examples of quadrature outputs and three phase outputs are analyzed, simulated and constructed by microcontroller.