Dealing with noise

In a previous post I explained the sources of (electrical) noise in test systems. Noise introduces error into measurements and will cause control systems to malfunction by responding to erroneous inputs. This post covers noise suppression strategies.

Have you ever stepped into a crowded restaurant and been hit with the cacophony of a mass of humanity all speaking at once? Like in the video below.

If you are far enough away a from a large crowd all you hear is an unintelligible din. But you are able to enter the crowd and carry on a conversation with individuals, while filtering out all of the garbled background noise. Why? Well, you’d have to ask a neuroscientist for a precise answer, but essentially the brain is able to “lock on” to a specific voice while filtering out all of the background noise.

The environment a test system operates in is no different. The world is awash in electronic noise. The test engineer is required to design a test system that will “lock on” to the signal of interest while filtering out all of the useless background noise. This is accomplished through a choice of transmission signal, cabling and wiring techniques, and using specialized circuit components such as signal conditioning modules (SCM).