Pinching Antenna-Enabled URLLC Downlink

This letter investigates power-efficient downlink transmission for a pinching-antenna system under ultra-reliable and low-latency communication (URLLC) requirements. Unlike existing works based on Shannon capacity, we explicitly adopt the finite-blocklength coding model and capture the coupling among signal-to-noise ratio (SNR), bandwidth, latency, and reliability. We first derive, for each user, the minimum received SNR that meets a given payload and block-error target, and show that the optimal transmit power then admits a closed-form expression as a function of the pinching-antenna position and per-user bandwidth. This yields an equivalent problem in only these two variable blocks. Leveraging this structure, we develop a low-complexity block coordinate descent algorithm: for fixed bandwidths, the optimal antenna position is a closed-form FBL-weighted centroid of user locations; for a fixed position, the bandwidth allocation subproblem is strictly convex and solved optimally via a dual-based bisection method. Simulation results demonstrate that the proposed pinching-antenna design significantly reduces the total transmit power compared with a fixed-antenna baseline, with robust gains across different payloads, reliability targets, and system geometries.