An uplink multiuser pinching-antenna system (PASS) is considered, where multiple dielectric waveguides are deployed at the base station and one pinching antenna (PA) is activated on each waveguide. For practical implementation, each PA is restricted to a finite number of preconfigured locations. The resulting uplink sum-rate maximization problem is represented as a layered tree search. Three algorithms are then developed: a greedy search (GS), a beam search (BeS), and an optimal branch-and-bound (BnB) search. In GS, the locally best branch is selected through efficient matrix-inverse updates. In BeS, several promising partial paths are retained to provide a tunable performance-complexity tradeoff. In BnB, noncompetitive subtrees are pruned through a monotonic transformed objective without loss of optimality. Substantial gains over a conventional fixed array are demonstrated by numerical results. Near-optimal performance is also achieved by GS and moderate-width BeS at a lower computational co t than BnB.
Pinching-antenna systems (PASS) offer considerable potential for wireless communications due to their unique ability to dynamically reconfigure radiation positions along a waveguide. However, the performance of PASS remains a critical challenge in the presence of random line-of-s…
A pinching-antenna system (PASS) is considered for over-the-air computation (AirComp). Multiple dielectric waveguides are deployed at the base station, and one pinching antenna (PA) is activated on each waveguide. For practical implementation, each PA is restricted to a finite se…
The pinching-antenna system (PASS) uses dielectric particles along a low-loss waveguide as reconfigurable passive radiators. Existing analyses conclude that the in-waveguide attenuation is negligible at low frequencies and millimeter wave bands; we show this fails at terahertz (T…
The performance of pinching-antenna systems (PASS) is fundamentally affected by line-of-sight (LoS) blockage in practical environments. In this paper, PASS is investigated under realistic, obstacle-induced blockage by jointly considering the LoS and non-LoS (NLoS) components, rat…
Pinching-antenna systems (PASS) are capable of dynamically reconfiguring wireless channels by flexibly repositioning pinching antennas (PAs) along the waveguides to establish short-range line-of-sight links. In this paper, a user-side navigation framework for PASS is proposed, wh…
In frequency-division duplexing systems, the performance gains of pinching-antenna systems (PASS) critically depend on accurate channel state information (CSI) at the base station. However, PASS CSI exhibits structured correlations over the waveguide-antenna grid and pronounced h…