Patent ID: 8037114

Claim:
An apparatus for calculating a signal energy of an information amplitude signal, comprising a transformer for decomposing an information amplitude signal into spectral values present in an x-bit representation with a logarithm not taken; a processor for performing a squaring at the x-bit representation with the logarithm not taken of each spectral value in order to receive a respective squared spectral value, and a summation at the squared spectral values in order to receive a sum of squares as a calculation result in a y-bit representation with the logarithm not taken, wherein the processor is adapted such that the representation with the logarithm not taken of the calculation result is scaled with an effective scaling factor compared to the sum of squares; a logarithm taker for applying a logarithm function to y bits of the representation with the logarithm not taken of the calculation result in order to receive a scaled representation with the logarithm taken of the calculation result, wherein y is less than or equal to 2 times x; and a rescaler for adding or subtracting a correction value to or from respectively the scaled logarithmic representation, the value corresponding to the logarithm function applied to the effective scaling factor, in order to receive a representation with the logarithm taken of the calculation result as the signal energy.