With the advent of integrated circuits (IC), digital systems have become widely used in modern electronic devices, including communications and measurement equipment. Direct Digital Frequency Synthesizers (DDS) are used in communications as transmitter exciters and local oscillators in receivers. The advantages are superior frequency stability, the same as that of the driving clock oscillator, and short switching times. The difficulties are lower output frequencies and rather large spurious signals.

Compiled for practicing engineers who do not have the prerequisite of a specialist's...