Patent ID: 8634273

Claim:
A method comprising: transmitting a data communication by an acoustic signal that is modulated within multiple non-overlapping passbands in a jointed tubing string, wherein the modulated acoustic signal is separately modulated in each of the multiple passbands; before transmitting the acoustic signal, selecting the multiple passbands to place each passband substantially within a respective range of frequencies that is passed by the jointed tubing string, and to place intermodulation distortion components in stop bands substantially within respective a ranges of frequencies that are blocked by the jointed tubing string; receiving the modulated acoustic signal from the multiple passbands at a location proximate the earth's surface; performing amplitude and phase equalization for each passband of the received modulated acoustic signal to generate an equalized signal for each passband, the equalized signals for different passbands being generated based on different respective parameters for equalization; and demodulating the modulated acoustic signal after performing the equalization for each passband.