A.A. Silkin - leading design engineer, JSC «Concern «Automation». E-mail: saa@oao-avtomatika.ru

The confidentiality is one of the three information security (InfoSec) attributes. Of particular importance it has in a special communication systems organization. Attackers typical actions directed against confidentiality are eavesdropping and Signals intelligence with the electromagnetic field. A radiation from protected space (in terms of InfoSec) (e.g., through windows) should be overlapped by noise. To evaluate degree of security (of information contained in signal) you can use indicators of noise effectiveness, namely, noise/signal ratio. Before a blocking any sources of data leak you should use special experimental investigations, but it may be expensive and time consuming. Therefore the method of statistical imitating modeling (SIM) finds here its application. In a number of previous articles distributions and descriptive statistics of power levels for the random aperture antennas (RAA) were obtained and identified. This article develops them logically. It describes results of a physical modeling, where distributions of power levels for RAA model were determined. These results were compared with those obtained using a simulation model. Also this article describes a selection of some area of input parameters for SIM-model, under which it is most closely match physical model RAA; also it considers a legitimacy of using a term «the phase error».