Patent ID: 7003536

Claim:
A method of operating a data processor to enable said data processor to perform a radix-4 fast Hadamard tranform, said method comprising the steps of: receiving an input sequence w 0 , w 1 , w 2 , w 3 ; first calculating a quantity wherein {tilde over (w)}=w 0 +w 1 +w 2 −w 3 comprise a first input, a second input, a third input and a fourth input of said radix-4 fast Hadamard transform, respectively; second calculating the quantities s 0 ={tilde over (w)}+2w 3 , s 1 ={tilde over (w)}−2w 1 , s 2 ={tilde over (w)}−2w 2 , s 3 =−{tilde over (w)}+2w 0 , wherein s 0 , s 1 , s 2 , s 3 comprise a first output, a second output, a third output and a fourth output of said radix-4 fast Hadamard transform, respectively; outputting said quantities s 0 , s 1 , s 2 , s 3 as results of said radix-4 fast Hadamard transform; and repeating said steps of receiving, first calculating, second calculating and outputting.