标量乘法是实现椭圆曲线密码体制的瓶颈问题,利用NAF编码、预计算表法和Yen-Laih法分别在三个阶段对Lim-Lee算法进行优化,新的定点标量乘算法在赋值阶段动态扫描矩阵宽度为W的非全零列窗口,结合2^kP底层域快速算法和扩充过的预计算表来提高计算效率。当位长是160时,新算法效率比Lim-Lee算法提高22.7%,192时提高23%,224时提高23.3%。
Scalar multiplication is the bottleneck of ECC.This paper optimizes the Lim-Lee algorithm with NAF method,precompute table and Yen-Lath method in three stages separately.The new fixed-point scalar multiplication algorithm dynamicly scans the matrix to get nonzero windows with length limited in w in the evaluation stage,and integrates with 2^kP field fast algorithm and extended pre-compute table to improve compute efficiency.When digit length is 160,the efficiency of new algorithm improves about 22.7% than Lim-Lee algorlthm,about 23% when 192 and 23.3% when 224.