Comparison of continuum light curves emitted by BBH systems when only the secondary BH is active with mass ratio q_M = 0.1 (left panel) and 0.5 (right panel) at i_obs = 60°. The black dashed line shows the light curve from the system with circular orbit (e = 0), the other four lines colored from blue to red show those resulted from elliptical orbits (e = 0.5), with four different position angles of their major axes ω varying from 0° to 270°. The horizontal dotted line shows the light curve without the Doppler Boosting effect.