To efficiently emit radio waves, the antenna itself should be separated in order to avoid degradation of characteristics. There are two ways to help avoid such degradation: physically separate the audio circuit from the antenna, and electrically isolate the antenna. As this slide illustrates, traditional cellphones initially utilized the first method. However, due to increasing circuit density of smartphones in recent years, it has become increasingly difficult to physically isolate the antenna. Thus, electrical isolation is often used. An example of electrical isolation is shown here. When using the NFZ series in this case, the power radiated from the antenna has shown great improvements.