METHOD, DEVICE AND PROGRAMME FOR EXPONENTIATING AN INDEPENDENT VARIABLE TO THE POWER OF A HIGH EXPONENT

摘要

The invention concerns a method using a processor (2) capable of processing words of length k bits, the exponent e being coded on I words of k bits, after generating powers of the argument x with an odd exponent between 1 and 2t-1, wherein t is less than k, each word coding the exponent e is processed from the most significant bit to the least significant bit, by scanning the current word by blocks of not more than t bits so as to scan each block by square exponentiation of a value y, for as many times as the number of bits of the scanned block.