Utilizing arbitrary waveform generators to produce noise with imposed spectral characteristics

The reliability and performance of many systems mostly depend of their noise rejection capability. The behavior of systems that are prone to noise is therefore investigated since the early production stage, as well as routinely during periodical maintenance actions. Actually, there are very few noise sources available on the market, the majority of which is capable of generating only noise characterized by a uniform power spectral density in a limited bandwidth; generators capable of producing colored noise are instead very rare. In theory, arbitrary waveform generators could be deployed and suitably programmed to serve as noise sources. But, the technicians charged of test and measurement assignments will barely find application notes that support them in stepping from theory to practice. This work presents tutorial notes related to the simulation of colored noise, and proposes an analog generator that exploits an arbitrary waveform generator as noise source. The proposed generator is capable of producing noise signals characterized by arbitrary power spectral densities.