Energy-harvesting technologies harvesting energy from ambient power sources, such as vibration, heat, and electromagnetic waves, have recently attracted significant attention. Among the multiple ambient energy sources, the wireless energy-harvesting technology has dramatically grown recently due to prevalence of wireless signals, such as TV, radio, cellular, satellite, and WiFi signals. In this project, existing work on antennas for energy harvesting will be reviewed, and an antenna array will be proposed to improve the antenna gain and energy harvesting efficiency. The antenna and the required RF circuit will be simulated separately, and linked together to form a rectenna (antenna + rectifier) array system. The performance of the newly proposed system will be compared to the existing ones and justify the feasibility of using antenna array for energy harvesting technology.