Design and Analysis of Pinching-Antenna Systems With Radially Deployed Waveguides (X-PASS)

Pinching-antenna systems (PASS) reconfigure the wireless channel by positioning dielectric antennas along a waveguide. A single waveguide, however, confines its antennas to one line, so that good coverage of an area has relied on several waveguides or waveguide segments with separate feeds. This paper proposes X-PASS, in which a hub feeds radially deployed waveguide arms, one pinching antenna on each, and drives them by arm selection, aggregation or multiplexing. It models the hub with its insertion losses, derives a unified signal-to-noise ratio expression for these three operating modes, and derives in closed form a radius inside which aggregation outperforms selection. Numerical results validate the analysis and compare the coverage of X-PASS with that of the other layouts at equal transmit power.