An　optical　configuration　design　is　presented　for　the　ground　testbed.　The　system　includes　three　sub-telescopes　as　the　collecting　elements,　and　a　combination　telescope.　The　goal　is　to　produce　an　image　with　a　＂quality＂　equivalent　to　a　filled　monolithic　aperture.　The　system　has　a　diffraction　limited　field-of-view　of　0.1　degrees.　The　subsystem　utilizes　non-spherical　primary　and　secondary　mirrors.　Also,　several　image　restoration　techniques　are　analyzed　in　details,　which　are　applied　to　sparse-aperture　imaging　system　in　frequency　domain.　The　performances　of　the　restoration　techniques　are　compared　under　different　circumstances,　such　as　the　aperture　configurations,　the　fill　factors,　and　the　level　of　noise.　The　correlation　coefficient　is　proposed　as　a　criterion　to　determine　optimal　parameter,　and　evaluate　the　performance　of　algorithms.　Simulation　results　demonstrate　its　possibility.　Some　suggestions　are　given　for　better　restoration　resolution　of　sparse-aperture　imaging　system.