20100008189 | METHODS AND SYSTEMS FOR COMMUNICATING DATA THROUGH A PIPE - An acoustic telemetry system includes a piezoelectric stack at least partially disposed within a segment of pipe, and electrical circuitry for controlling the piezoelectric stack. In response to a signal from the electrical circuitry, the piezoelectric stack generates a plurality of acoustic signals for transmission through the pipe at different frequencies spanning multiple regions of a frequency response for the pipe. | 01-14-2010 |