  The report presents a general approach for estimating quantum information
technologies by means of fuzzy quantum measurements. The developed methods are
used for precision reconstruction of quantum states under conditions of
significant influence of decoherence and quantum noise. Monitoring of the
amount of information about quantum states and their parameters, including the
loss of information caused by the effect of quantum noise, is considered.
Examples of the developed approach as applied to readout errors and phase
relaxation are presented.
