Methods for digitizing weak signals much less the LSB level

Abstract

In contemporary software definer radiodevices (SDR), processing of signals is carried out in a digital kind, since entrance cascades of a high-frequency path. The contradiction between very small (by level) analog signals and large value of the least significant bit (LSB) is removed by addition of the vobulation noise. The size and a kind of distribution of this noise essentially influence quality of reception in the whole. In the article, means of the MATLAB system are used to, research of opportunities of numbering of signals, which level much is less than the minimal category of quantization. The empirical expressions for calculation of potential characteristics of transformation of weak signals in ADC are received. It is shown that at the offered numbering there are no combinational handicapes. Results of experimental confirmation of adequacy for models of digital reception of weak signals are obtained.