On the Phase-Compensated Long-Range VNA-based Channel Sounder for sub-6 GHz, mmWave and sub-THz frequency bands

This paper presents an overview of the vector network analyzer (VNA)-based phase-compensated channel sounder at sub-6 GHz, mmWave, and sub-Terahertz (sub-THz) bands. The optical cable solution can enable long-range channel measurements for all these three bands, since it can effectively minimize the cable loss. The phase compensation architecture and principle are also discussed in this paper. The accurate phase measurement is enabled by the phase compensation scheme, which is essential for application in multi-channel/antenna measurements. We summarized the performance of the designed channel sounder under two types of cable effect condition, namely thermal changes and mechanical stress. Under these two cable conditions, the phase compensated channel sounders are validated in back-to-back measurements. The compensated phases demonstrate the robustness and effectiveness of these channel sounder for the frequency bands of 1-30 GHz, and 220-330 GHz.