Dissertation Title: Channel Measurement and Modeling for Terahertz Communications with Various Antenna Configurations
Date: 2026/01/26 – 2026/01/26
Dissertation Title: Channel Measurement and Modeling for Terahertz Communications with Various Antenna Configurations
Speaker: Yiqin Wang, Ph.D. candidate at SJTU Global College
Time: January 26th from 3:15 p.m., 2026 (Beijing Time)
Location: Room 403, Longbin Building
Abstract
Terahertz (THz) communications, generally defined as occupying the region of 0.1-10 THz in the electromagnetic spectrum, are envisioned as a key technology to fulfill future demands for sixth generation (6G) and beyond. Main features of the THz band include the broad bandwidth ranging from tens of gigahertz (GHz) to possibly hundreds of GHz, the high propagation loss, and the vulnerability to line-of-sight (LoS) blockage, among others. Therefore, on one hand, wireless communications leverage the large bandwidth of the THz band to achieve high-speed data transmission in classic indoor and outdoor scenarios using single-antenna-to-single-antenna systems. On the other hand, to compensate for the challenges of high transmission loss and LoS vulnerability, and benefiting from the short wavelength, technologies like extremely large-scale antenna arrays (ELAA) and position-flexible antennas (PFA) have been proposed. Consequently, a wide variety of antenna configurations may be employed in THz communication systems. As wireless channels are the foundation for designing wireless communication systems, it is imperative to study the THz radio propagation channels for THz communications with flexible antenna configurations.
This dissertation deeply studies channel measurements, characteristics and modeling methodologies for THz communications with flexible antenna configurations, including single-antenna, ELAA, and PFA systems. First, as the essential step for subsequent channel characterization and modeling, the author first reviews the channel measurement data post-processing and proposes a physically interpretable and self-adaptive multi-path component (MPC) clustering algorithm. Inspired by the concept in geography, a novel metaphor that interprets features of MPC attributes in the power-delay-angle profile (PDAP) as topographic concepts is developed. In light of the interpretation, the proposed algorithm disassembles the PDAP by constructing contour lines and identifying characteristic points that indicate the skeleton of MPC clusters. The skeleton of clusters, associated with single-point or wide-spread scatterers in the physical environment, is utilized for the improvement of clustering results. Besides, the author develops a new clustering performance index, the weighted Spearman correlation coefficient between the power and the distance to the cluster center, which captures the intrinsic property of MPC clusters that the dominant high-power path is surrounded by lower-power paths. The performance of the proposed algorithm is analyzed and compared with the counterparts of conventional clustering algorithms based on the channel measurement conducted in an outdoor scenario. The proposed algorithm performs better in average Silhouette index and weighted Spearman correlation coefficient, and the average root-mean-square error (RMSE) of the estimated scatterer location is 0.1 m.
Then, THz channel measurement, analysis and modeling are conducted for systems with different antenna configurations. First, for single-antenna systems, a dual-band angular-resolvable wideband channel measurement in an L-shaped hallway is presented and THz channel characteristics at 306-321 GHz and 356-371 GHz are analyzed. In light of the measurement result, a generic L-shaped intersection scenario model is developed, and the ray-tracing (RT)-statistical hybrid channel modeling method is adapted for THz channel characteristics in the non-line-of-sight (NLoS) scenario. Especially, the spatial consistency of reflected MPCs in the NLoS region is analyzed, and the continuous change of dominant MPCs is statistically modeled, in terms of their power, delay and angles of arrival. Besides, a modified alpha-beta (M-AB) path loss model for the NLoS region is proposed, which is shown to reduce the mean square error (MSE) between the model predictions and actual measurements by 80% across different frequency bands. Second, the author carries out cross-field channel measurements and proposes a cross-field channel model for ELAA systems, by completing the characterization of MPC parameters including propagation time and departure/arrival angles in near-field (NF) and far-field (FF) fields, respectively. Based on this model, extensive simulations are performed for ELAAs of varying sizes in indoor and urban macro-cell scenarios at frequency bands ranging from sub-6 GHz, millimeter-wave, and up to THz. By considering the spherical-wave front as the ground truth, the cross-field model exponentially enhances the accuracy in characterizing multi-path parameters and evaluating the system capacity. Third, the author fills the gap in experimental analysis on THz PFA systems by developing a broadband channel measurement with physical PFA operating in the THz band. Then, a spatial-correlated channel model for the two-dimensional PFA is proposed, which is statistically parameterized by the complex covariance matrix extracted from the measurement. Furthermore, by applying either the antenna selection algorithm, PFA systems are verified to achieve 99% of the optimal performance in terms of spectral efficiency. Extensive results demonstrate the advantage of PFA over fixed-position antennas in coping with the multi-path fading and improving the spectral efficiency by over 10% at 300 GHz.
Biography
Yiqin Wang received the B.E. degree in Electrical and Computer Engineering from Global College, Shanghai Jiao Tong University, Shanghai, China in 2020. She is currently working toward the Ph.D. degree with Terahertz Wireless Communication (TWC) Laboratory, Shanghai Jiao Tong University, Shanghai, China. Her research interests include channel measurement and modeling in the Terahertz band.