The orbit of LISA around the sun modulates a monochromatic gravitational wave in a way that depends on the celestial coordinates of the source of the gravitational wave.
The figures show line spectra for 1 year of integration for two different source locations. The frequency of the gravitational wave is 3 mHz and the dimensionless amplitude h+ is 1.
From LISA System and Technology Study Report (2000) (Fig 7.12 & 7.13)
ESA-SCI(2000)11