  The concept of aperture selection is proposed for continuous aperture array
(CAPA)-based communications. The achieved performance is analyzed in an uplink
scenario by considering both line-of-sight (LoS) and non-line-of-sight (NLoS)
scenarios. In the LoS scenario, the optimal selection strategy is demonstrated
to follow the nearest neighbor criterion, and the resulting signal-to-noise
ratio (SNR) is analyzed. In the NLoS scenario, the achieved outage probability
along with the diversity order is revealed. Numerical results are provided to
demonstrate that aperture selection effectively maintains satisfactory
performance by leveraging selection diversity while simultaneously reducing the
implementation complexity of CAPAs.
