Communication in pipes using acoustic modems that provide minimal obstruction to fluid flow

An acoustic communication system for use in a tubulation, comprising:

• a tubulation having a first end and at least a second end;
• a plurality of phased array acoustic communication devices, each of said plurality of phased array acoustic communication devices configured to send acoustic signals and to receive acoustic signals, a first one of said plurality of phased array acoustic communication devices situated proximate to said first end of said tubulation and having at least one input port for communication with a controller and having at least one output port for communication with said controller, and a second of said plurality of phased array acoustic communication devices situated at a distance from said first one of said plurality of phased array acoustic communication devices, said second of said plurality of phased array acoustic communication devices configured to communicate with and to receive instructions by way of said first of said plurality of phased array acoustic communication devices;
• and
• a controller configured to activate said one of said plurality of phased array acoustic communication devices by way of said input port, configured to receive a signal from said one of said plurality of phased array acoustic communication devices by way of said output port input terminal and configured to provide at a controller output port an electrical signal representative of an acoustic signal received by said one of said plurality of phased array acoustic communication devices.