LoS Blockage in Pinching-Antenna Systems: Curse or Blessing?

TL;DR

This work analyzes how line-of-sight (LoS) blockage affects pinching-antenna downlink networks. It develops analytical models for both single-user and multi-user scenarios, employing two precoding designs: a zero-forcing design for full-rank channels and a low-complexity per-user scheme. The results show that LoS blockage can significantly improve the performance of pinching antennas relative to conventional antennas, with particularly strong benefits in multi-user settings where blockage suppresses interference, leading to unbounded rate gains at high SNR. Numerical studies confirm the theoretical findings and demonstrate the practical impact for dense, indoor, or ultra-dense networks where pinching antennas offer low-cost, reconfigurable MIMO capabilities.

Abstract

This letter is to investigate the impact of line-of-sight (LoS) blockage on pinching-antenna systems. Analytical results are developed for both single-user and multi-user cases to reveal that the presence of LoS blockage is beneficial for increasing the performance gain of pinching antennas over conventional antennas. This letter also reveals that LoS blockage is particularly useful in multi-user cases, where co-channel interference can be effectively suppressed by LoS blockage.

Figures (4)

• Figure 1: Ergodic data rates achieved by the considered transmission schemes for the single-user special case. $D_{\rm W}=10$ m, $D_{\rm L}=4D_{\rm W}$, the blockage model in \ref{['blockage']} is used, and $\phi=0.1$.
• Figure 2: Outage probabilities achieved by the considered transmission schemes for the single-user special case. In both figures, the transmit power is $10$ dBm, and Case II is considered. In Fig. \ref{['fig2a']}, $\phi=0.1$. In Fig. \ref{['fig2b']}, $D_{\rm W}=5$ m, and the analytical results are based on Lemmas \ref{['lemma1']} and \ref{['lemma2']}.
• Figure 3: Ergodic sum rates achieved by the considered transmission schemes for the multi-user case. In both figures, $D_{\rm W}=10$ m, $D_{\rm L}=4D_{\rm W}$, the blockage model in \ref{['blockage']} is used, and $\phi=0.1$.
• Figure 4: Ergodic data rates achieved by the considered transmission schemes for the special case considered in Section \ref{['section 4']}. $D_{\rm W}=10$ m, $D_{\rm L}=4D_{\rm W}$, Design 2 is considered, and the blockage model in \ref{['blockage2']} is used. The shown analytical results are based on Lemma \ref{['lemma3']}.