Signal generation and stabilization techniques for sub-THz transceivers

Abstract

The sub-THz band, defining 100−300 GHz, has been getting attention as a frequency band for next-generation wireless communications. An ultra-wide bandwidth of this frequency band is suitable for high-data-rate wireless communications. However, the performance of the CMOS transceiver is rapidly degraded due to the high operating frequency. Among them, the LO signal requires high spectral purity, which is an essential part of the transceiver. In addition, the output power of the LO signal is also necessary, which affects the conversion gain in the transceiver. Therefore, a sub-THz signal source with high output power and low phase noise is proposed in this dissertation. For implementing the sub-THz signal source, a D-band harmonic VCO and an H-band frequency doubler are presented, which generates a sub-THz signal. Furthermore, a cascaded sub-sampling PLL is proposed for the frequency stabilization in the sub-THz band, and a dual path sub-sampling phase detector is presented to improve the performance of high-frequency sub-sampling such as error-detection gain. This dissertation proposed and demonstrated signal generation and stabilization techniques for sub-THz transceivers.