A 138-GHz Dielectric Waveguide Link with 4.87 pJ/bit Efficiency in 28-nm CMOS

This work presents a fully integrated 138-GHz Dielectric Waveguide (DWG) communication link in a 28-nm CMOS process, addressing the critical challenges of high cost and excessive power consumption in DWG interconnects. The proposed low-cost packaging scheme, combining wire bonding, SIW transition, and transverse aperture coupling, achieves a low coupling loss of 5.2 dB. The dynamic bias adjustment of the PA and LNA enables power consumption optimization for different link lengths. Measurement results demonstrate that the link delivers a state-of-the-art energy efficiency of 4.87 pJ/bit at 1.5 m with a data rate of 17 Gbps. Although the data rate declines at 3 m, it still reaches the theoretical maximum rate predicted by the dispersion factor model, validating the effectiveness of the system design.