In　this　paper,　the　problem　of　high　mobility　channel　estimation　in　the　Long-Term　Evolution　for　Railway　(LTE-R)communication　system　is　investigated.　By　using　a　Basis　Expansion　Model　(BEM),　the　channel　impulse　response　is　modeled　as　the　sum　of　several　basis　functions　multiplied　by　coefficients.　By　estimating　the　basis　function　coefficients,　the　fast　time-varying　channel　can　be　approximated.　In　order　to　reduce　the　estimation　error　resulting　from　the　high　frequency　basis　function,　the　Generalized　Complex　Exponential　BEM　(GCE-BEM)is　modified　to　form　an　Improved　GCE-BEM　(IGCE-BEM)by　adding　a　correction　coefficient　to　the　basis　function.　Moreover,　an　Improved　Baseline　Tilting　(IBT)method　is　proposed　to　reduce　the　Gibbs　effect.　In　addition,　linear　interpolation,　Gauss　interpolation,　and　three-order　Hermite　interpolation　are　adopted　to　obtain　the　channel　impulse　response　at　non　pilot　locations　based　on　the　channel　estimation　results　at　pilot　positions.　The　simulation　results　show　that　the　IGCE-BEM　outperforms　the　CE-BEM　and　GCE-BEM　in　terms　of　the　Normalized　Mean　Squared　Error　(NMSE).　The　IBT　method　is　better　than　the　BT　method　in　reducing　the　Gibbs　effect.　In　addition,　combined　with　the　IBT,　the　IGCE-BEM　also　has　low　NMSE　under　high　moving　speed　and　high　noise　power.　The　performance　of　the　three-order　Hermite　interpolation　method　is　higher　than　that　of　the　linear　interpolation　and　Gauss　interpolation　approaches.　©　2018　Chongqing　University　of　Posts　and　Telecommunications