国家重点实验室 Recursive construction of W XN=uNG ,N=2” 41 V2 Gw=(I.⑧F)Rw(L2⑧Gw) uN2-1 ⊕'w2 WN2 VN/21 =By FOn uNn-H SNI2 'N2 -yN2-1 yNn2 uN12+1 SN12+1 RN VNI2L -yN21 uN2+2 VNI22 o here -yw/242 1 0 SN-1 WNI2 11 uN-+⊕ VN1 YN- VN yN ⑧Kronecker Product R:reverse shuffle operation WN By bit-reversal operator if yN=uN By,then va.b=u 18Recursive construction of WN here 18 : reverse shuffle operation : bit-reversal operator R N 1 1 N N N x uG = n BN F ⊗ = 2 2 2 ( )( ) N NN N G I FR I G =⊗ ⊗ 1 0 1 1 F   =     BN 2 n N = 1 1 . . if , then n n N N N bb b b v uB v u = = ⊗ Kronecker Product