Metrel (Slovenia)

The systematic bias error of the non-parametric frequency estimation due to leakage effect can be effective reduced by the interpolated discrete Fourier transform. For fast decline of the long-range leakages the Rife-Vincent windows are used and the RV class II windows perform the lowest bias error.

High quality analog-to-digital (A/D) conversion is obtained using the non-uniform exponential tracking procedure. Samples of the analog signal and differences of the previous estimations are cycled rapidly through a non-uniform coarse quntizer while the round off error is fed back and subtracted from the input. It has been shown that the proposed A/D conversion gives better results than a classical A/D conversion with the successive approximation procedure due to b-times more available sampling points and the adaptive property of the A/D procedure that every previous approximation step to signal become the centre of observation with exponential increasing resolution in the new step. Evaluation of the exponential tracking A/D conversion performs better results considering both systematic and random errors than the tracking A/D procedure with a uniform quantization.

State-of-the-art information technology enables a variety of specific metrological applications. The first benefit for the metrology community is in significantly increased remote functionality of the measuring systems (e.g., connected in distributed legal metrology measuring systems, or remote operation of the measuring instruments in severe environmental conditions). The next significant improvement comes from the introduction of new metrological services (e.g., time service, remote calibration, and remote software validation). Finally, it is important to mention the increased availability of the metrology-related information which is available on the World Wide Web. Presented approaches and solutions are not exclusively specific for the metrology community; however, it is important to mention them in order to make metrologists aware of their existence. This chapter is not an attempt at giving the complete overview of available solutions, but rather the first insight into the mentioned areas which will be the starting point for further investigations.