由x(n)=Re[v(m)得 X(k)=DFTIX, (n)= DFTRelw(n)=Wen(k) WW((K))N+W((N-KDNIrn(k) 由x2(m)=Imw(n)得 X(k)=DFTIx, (n]= DFT(Imw(n==Won(k) 2 W(K)N-W((N-k)R(k)1 由 得 x n w n ( ) Re[ ( )] = 1 1 ( ) [ ( )] {Re[ ( )]} ( ) X k DFT x n DFT w n W k = = = ep 1 * [ (( )) (( )) ] ( ) 2 = + − W k W N k R k N N N 2 由 得 x n w n ( ) Im[ ( )] = 2 2 1 ( ) [ ( )] {Im[ ( )]} ( ) X k DFT x n DFT w n W k op j = = = 1 * [ (( )) (( )) ] ( ) 2 W k W N k R k N N N j = − −