A Novel Data Compression Technique for 420 Ma Current Loop Transmitters

Abstract

This paper presents a new data compression method for current loop transmitters. In this method, the 4-20 mA current domain is divided into some equal pieces that are used for distinct data domain with a constant relative resolution, resulting in widening the signal span. This technique eliminated the need for high resolution ADC’s or DAC’s in communication of 4-20mA current loop signals. Furthermore, because of high amplitude of current steps the sensitivity of transmitter and receiver to noise and interference is reduced. As this is a software-based technique, there is no need to change the structure of the intelligent transmitters.