RF-MEMS for 5G mobile communications: A basic attenuator module demonstrated up to 50 GHz

After fluctuating expectations and disillusionments, RF-MEMS technology is starting to make its way into market applications. To this regard, the upcoming field of 5G seems to be the fitting application area for such a technology to fully express its potential. In this work, we present an RF-MEMS basic 2-state attenuator module, simulated and measured up to 50 GHz. A series resistive load, inserted on the RF line, can be shorted by electrostatically actuating a suspended Gold thin membrane. When the load is inserted, a rather flat attenuation level (S21) is observed over the whole range, it spanning from −9 dB to −6 dB as the frequency increases. On the other hand, when shorted, the module exhibits a loss (S21) better than −1.4 dB up to 50 GHz. The discussed basic module can then be exploited as building block to implement more complex RF signal conditioning functions.