Signal-to-noise ratio of the 21cm–LAE cross-power spectrum P_21, LAE(k) as a function of wavenumber k for different observational configurations. The top, middle, and bottom panels correspond to varying FoV, galaxy redshift uncertainty, σ_z, and minimum Lyman-α, luminosity L_α^min, respectively. The 21cm signal noise is computed assuming the SKA-Low1 AA4 antenna layout and a moderate foreground model.