Improve the resolution of analog digital conversion by software processing

This paper proposes a method to improve the resolution of analog to digital conversion by software. It is based on the statistical characteristics the AD sampling data and their uncertainty, and suitable to process slowly varied signal with some noise distribution. It provides an idea to select an ADC through eclectic consideration of hardware and software. So the system complexity and cost are lowered. Applications in chromatograph and thermocouple adjuster are introduced.

I. Introduction

In the automatic digital measurement and control systems, some applications demand high-resolution analog to digital conversion. It is a usually method for users to select ADC hardware unit according to the required measurement or control resolution. For example, to obtain a measurement resolution of 0.001%, the ADC resolution is selected to be 17 bits (about 0.0008%) or higher. Obviously, the higher the ADC resolution is, the more complicated and expensive the hardware circuit. So it is desired to improve the ADC resolution using software processing.