Design considerations for 5G mm-wave transceivers

To meet the yet higher speed and capacity demands, 5G is turning to mm-waves for more bandwidth. In this presentation, some transceiver design issues occurring when moving from current 4G frequency bands to mm-wave frequencies are discussed. The local oscillator phase noise increases with carrier frequency by 6dB/octave and will ultimately limit the spectrum efficiency. Further, the receiver noise figure will also degrade as the carrier frequency increase and the devices operate close to their transition frequency. A thorough analysis of the wideband receiver noise figure that shows the expected noise figure increase when shifting from a few GHz to mm-wave carries frequencies will be provided. By taking advantage of the anticipated improvements from CMOS scaling we also make some predictions 10 years from now. The 5G system is presently being standardized in 3GPP, but future improvements in technology must be considered in this work to predict what performance can be achieved once the system is in full use. Expected performance figures of frequency synthesizer phase-noise, receiver noise figure, ADC and DAC, as well as, integrated PAs are discussed and exemplified by experimental results from circuits manufactured in 28nm FD-SOI. The presented mm-wave integration aspects also account for beamforming and array antennas, how this relates to building practice, power consumption, and area to clarify how they fit to the targeted system.