Techniques are presented herein for distinguishing between the DC component of a real signal and DC energy of a received signal due to the radio receiver circuitry. Samples are obtained of a received signal derived from output of a receiver of a communication device. A mean of the samples is computed over a sample window comprising a predetermined number of samples. First and second thresholds are provided, the first threshold being greater than the second threshold. An absolute value of the mean is compared with respect to the first threshold and the second threshold as samples are obtained in the sample window. A selection is made between the first threshold and the second threshold for purposes of comparison with the absolute value of the mean to determine whether energy at DC is a true/real DC component of the received signal or is due to circuitry of the receiver.