Thermal Radiation Measurement With Thermoresistive Sigma–Delta Modulator

This paper presents a radiometer project based on a sigma-delta modulator. A model of the static and dynamic instrument behavior is made, relating the parameters of a sensor/heater to noise and measurement error. It is shown that the output binary code has a linear relationship with the power being measured independent of the sensor's nonlinearity. Experimental results obtained from a prototype ratify the results predicted by modeling, showing that this approach can be useful as a basis for generating a digital output related to the unknown power.