<p>A system and method for transmitting mud pulse signals in a downhole environment is disclosed. In one embodiment, a mud pulser system includes a valve (32), a wire (26) comprising shape memory alloy (SMA), and operable to have a first shape at a first temperature and a second shape at a second temperature; a thermal energy source (18) to heat the wire (26) from the first temperature to the second temperature; and a valve poppet (32) coupled to the wire, wherein the valve poppet is extended to close the valve when the wire is in the first shape and wherein the valve poppet is retracted to open the valve when the wire is in the second shape.</p>
