In addition to the benefits listed, there are also some challenges in applying a loaded PIFA. The PIFA is a unique antenna type. It is not commonly known and can not be treated the same in implementation as most of other antenna types (Patches, monopoles, and etc.) The antenna elements are connected to ground causing strong relation between antenna performance and PCB features. Because of this, the Board is part of the radiating structure; the whole board couples to body tissue in close proximity to the board. With the loaded PIFA, this coupling does not cause much detuning in frequency but degrades the total radiation efficiency. All electrically small antennas with ground connections suffer from the same effect to some degree.