Abstract: This paper firstly introduces the meaning and prospects of simultaneous wireless information and power transmission network (SWIPT). And then designs the model of SWIPT system. For problem of optimizing harvested energy, we point out a method of optimizing harvested energy and build the related model. Due to this model is a non-convex problem and is hard to be solved, we transforms it into a solvable convex problem by semi-definite program (SDP). Finally, we use the Matlab software to simulate and verify that MISO system has a better performance. In addition, we conclude that with the increasing number of antennas, the energy receiver can harvest more energy.