As is well known, the logarithmic system of nomenclature when estimating the level of signals or interference uses decibels, in which the following formula is used for the ratio of powers: N_p(dB)=10log(P_2/P_1), While for voltage(or currents)the following formula is used: N_U(dB)=20log(U_2/U_1). Here and henceforth quantities in logarithmic units will be distinguished by semibold type. The drawbacks of this system have been considered in detail in[1]whit numerous references to other publications. These drawbacks consist not only of the fact that there is ambiguity(different formulas for the power and the voltage)or in The inconvenience of memorisation[2], but also of the fact that it is difficult to change to logarithmic units in the case of other Non-energy quantities.
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