Design of CMOS – GaN hybrid mm-wave transceivers

The last decades, wireless communication showed a tremendous evolution resulting in ever higher communication speeds. The wide public standards evolved from 2G to 4G which is most common today. To deal with the need for ever increasing communication speeds, higher radio frequencies are being used and this has resulted in the 5G standard, which is starting to find its way in current cellphones. This standard defines multiple frequency bands, some of which being in the mm-wave range and new ones are still being reserved.

Operation at mm-wave frequencies comes with its own challenges. One of the main challenges is to deliver sufficient RF power at mm-wave frequencies with sufficient linearity, to enable complex waveforms and related high communication speeds, and efficiency to limit the environmental impact, improve battery life of handheld devices and limit heat dissipation. Advanced III-V technologies such as RF GaN have the potential to deliver power efficiently but they lack the high level of integration and complexity possible in CMOS.

During your PhD you will design mm-wave PAs in an advanced RF GaN process aimed for the upcoming FR3 bands from 8 to 24GHz. You will go beyond the traditional PA architectures typically used in III-V designs and add a level of complexity by leveraging on design techniques known from CMOS RF design. As this complexity is not fully implementable in GaN, you will define an architecture in which CMOS and GaN are combined through heterogeneous packaging so that both technologies are employed at their best and the sum is outperforming today’s solutions. Depending on the architecture you will propose, you will also design the CMOS circuits in an advanced process.