Various embodiments associated with use of an echo signal are described. A plurality of sensors can be deployed to obtain editions of a signal of interest. The signal of interest may be so far away from the sensors that the editions collected are too noisy to be analyzed. A processing center can send an echo signal to the sensors and the sensors can respond to the processing center with a signal edition of the signal of interest and the echo signal. Since the processing center knows information about the echo signal, offsets among the sensors can be calculated based on the returned echo signals. These offsets can then be used to align the signal editions. At the processing center, the aligned signal editions can be combined into a combined signal and a demodulation scheme for the combined signal can be determined and then used for demodulation of the signal.