The 5G Effect on RF Filter Technologies

A great deal is being written about the next generation mobile standards, “5G.” As with the early stages of previous generations, it is hard to clearly see the direction forward. The intersection of technological obstacles, economic realities, and political forces produces a path that is not only difficult to predict but curiously interesting in retrospect. Even with this history we press on and predict-it is our way. Even with all the publications on 5G and its many technical challenges there is a dearth of information on the radio frequency (RF) filters required. This is somewhat surprising as filters have become a major part of the radio in a mobile phone. State of the art smartphones now contain more than 60 filters and command the largest share of the RF wallet. The key starting point is the proposed new RF bands that will be used for 5G. The FCC has recently proposed band sections between 3.5-6 GHz, 27-40 GHz, and 64-71 GHz. As anyone familiar with radios in these areas knows, each band commands its own set of issues and solutions. The span of filter solutions for 5G will be more diverse than in the current mobile technology bands.