Microwave Transistors - The Backbone of 5G and Beyond Communication Systems

The era of global mobile connectivity began more than 40 years ago with the introduction of the first generation (1G) of mobile communication systems in 1979. With 1G it became possible to exchange voice messages between interlocutors being in the same building or thousands of miles apart without the need for a fixed line. Meanwhile 5G systems are in operation, much more than just voice messages are exchanged, and the mobile data traffic is growing extremely quickly. Therefore, higher frequency bands have to be used for mobile data transmission. In the present paper we discuss the status of microwave transistors, which represent the backbone of the hardware of mobile communication systems. Furthermore, we deal with the questions if microwave transistors operating properly in the upper frequency bands allocated for 5G communications are at hand and whether transistors for the 100 GHz … 3 THz range envisaged for beyond 5G systems are feasible.