This paper presents innovative schemes of “full-flash” and “subranging” A/D converter architectures. These new architectures are based on a conversion technique inferred by an electrical interpretation of the calliper rule. This kind of ADC implementation allow the dramatic reduction of the required resistors. Indeed, while a traditional full-flash or subranging ADC requires a voltage comparison scale realized by a series of 2n resistors, being n the number of bits of the resulting binary samples, the proposed architectures require only 3*2n/2 resistors. This reduction produces an obvious advantage in general case but can render possible the realization of full-flash ADC of large word lengths.

From many years in various science and technical areas there are introduced data fusion methods, lately also in metrological applications. Now there are conducted investigations connected with determining of importance of data fusion in classical metrology, complex measurement systems and also in measuring-control, diagnostic, classification systems, etc. The paper presents author’s point of view on data fusion process. It pointed that using of data fusion methods in metrology is possible and purposeful. Data fusion process in the paper is presented on example of the phase angle measurement method with improved tolerance on harmonic distortions. The purpose of data fusion in this case is reduction of basic error of analysed method. It has been proposed introduction of an additional data processing line (as a source of new information in measurement process), and shows a method for combining information acquired from these two lines. The analysis presented in the paper indicates that using the method of information combining (data fusion) in measurement applications brings measurable effects (basic error of considered system lowered more than 200 times).

The comparative analysis of lossy transformation compression algorithms for measurement signals is presented in the paper. A limiting error criterion and testing signals of synthetic character were proposed for comparing the compression algorithms. The application of such algorithms to test the lossy compression algorithms makes the results obtained in such a way independent of the shape of a single signal and makes them valid for the whole class of measurement signals while the determined limiting errors assume the character of maximum errors. By varying the parameters of the synthetic signals the operation of algorithms can be tested within certain intervals of signal parameter variability, not for single values of these parameters as it occurs for real measurement signals. The DCT, DST, DFT, DWHT, and DWH transformation algorithms were compared for various transformation orders and the classes of signals with single limit (variability range) or two limits (variability range and signal variability rate).

A bridge, suitable for 1:1 and 10:1 ratio measurements of four terminal-pair impedances to frequencies up to 5 MHz, has been constructed and is presently under testing. The purpose of the bridge is to extend the Italian national standard of capacitance toward higher frequencies; however, the bridge will be employed for resistance comparisons also. Expected best uncertainty is in the order of a few parts in 10-5 for 10 nF - 1 nF ratio measurements, at 1 MHz.

In this paper we present a technique to improve the accuracy of a measurement system. This technique is based on the arithmetic of the integer numbers in finite fields and represent an extension of the well known “calliper rule”. The said technique is explained by using some simple measurement examples, in particular length, time and mass measurements. Some related possibilities of improvement for the modern instrumentation are suggested and discussed.