To overcome 6G design challenges, new RF designs are proposed to cover three dimensions: Extreme high data rate, Extreme coverage, Extreme low energy. To accelerate 5G Gigabit speed to achieve 6G extreme high data rate, e.g., Terabit, we will use three techniques: (1) broad bandwidth: Our group demo 65% fractional bandwidth linearization to provide less power back-off, around 3.7 dB, from OP1dB to 64-QAM output power at 38 GHz. (2) High-order modulation: Our 28GHz Class-F PA provides over 20% PAE@EVM and 22.5dB Gain for 64QAM. 1024QAM/4096QAM OFDM are also measured. (3) MIMO: Our dual-polarization Rx can demo record-high spectral efficiency up to 12 bit/s/Hz at 60GHz.
To explore 6G extreme coverage, scalable phased array concept is demonstrated by NTU’s 38-GHz 32-element vertically assembled array. To illustrate microwatt RF designs for 6G extreme low energy, NTU has many published microwatt receivers from 5GHz to 60GHz, which is essential for 6G extreme low energy applications.
For future EHT THz telescope, our group will continue previous 230-GHz Rx development (first black hole image at 2019) to pursue extreme low temperature circuit design and measurement.