Using Noise Addition To Improve Measurement Precision

What do you think when you read the title of this post? Normally, in any measurement, noise addition to the signal acquired from a measuring transducer is the source of imprecision, then how can I say that we can also use a noise to improve the measurement precision? Yes, we can ad a noise to the acquired measurement signal to improve its precision.

Have you ever made repetitive measurement to obtain a measured value? You take the measurements for many times and then compute the averages of them. Usually, such multiple measurement to get more confident result is applied when a measurement is not precisely reproducible, so you’ll get confuse deciding whether you have to choose the value from the first or the second measurement. Just make multiple measurement and average it. If you get a same result from multiple measurement because you have a good enough instrument then it waste your time to repeat your measurement.

In analog-to-digital converter (ADC) , the precision of the reading depends on the bit resolution of the ADC design. Oversampling technique has been a common method to obtain higher resolution by averaging multiple reading. In the absence of noise, multiple reading will result in same values, making it useless to average them. The solution is by adding some noise to the signal that need to be measured by the ADC. Example of practical implementation of this technique, triangular dithering, is presented by Dave Van Ess in his article: Squeeze 10-Bit Performance From An 8-Bit ADC published in Electronic Design Magazine.

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