Method and device for determining a measured value indicating the degree to which data signals are reproducible outside a digital information processing system

摘要

In the neighbourhood of information processing and telecommunication systems, data signals, which are exchanged within that system, can, due to electromagnetic emission outside the relevant system, to a greater or less degree, be received - in a wireless way - and - generally after the received signal has been restored - be reproduced and displayed. The present invention relates to a measuring method and a device for determining a characteristic value indicating the degree to which data signals of a digital information processing system are reproducible outside that system. According to the invention a signal (3) received outside the information processing system to be tested is compared with a threshold value (5), and converted into a binary signal (6), of which the relatively shortest time (t₀) between two consecutive starting times of the ascending pulses is determined, said characteristic value being proportional to that number of ascending pulses for which it applies that the time (tx) between the starting time of that ascending pulse and the starting time of the ascending pulse preceding that pulse is, within certain tolerances, equal to {(n *t₀) / 2}, in which t₀ represents said relatively shortest time and n is a random natural number from the series {3,4,5,...}.