Abstract: The unified architecture of modular inversion over GF（p） is presented based on modifying four different types of modular inversion algorithm.The four modular inversion operations are combined in one architecture，which can perform Montgomery or classical modular inversion in terms of the selected signal and doesn’t increase extra cost.It is captured in VHDL，then complied，synthesized and fitted into FPGA.The result indicates that the design saves almost 50% hardware cost compared with two different architectures.

Key words: ECC, finite prime field, architecture of modular inversion, Field Programmable Gate Array（FPGA）

摘要： 在对四种不同类型的求模逆算法进行改进的基础上，提出了一种统一的有限素数域上的模逆运算结构。该结构结合这四种类型的模逆算法，通过选择信号完成Montgomery模逆或一般整数模逆运算，而不增加其它的硬件资源消耗。最后对该结构采用VHDL硬件描述语言进行了代码设计，并基于FPGA进行了编译综合和布局布线。实验结果表明该设计与采用两种不同结构分别计算的方案相比，节省近一半的硬件资源。

关键词: 椭圆曲线, 有限素数域, 模逆运算结构, 现场可编程门阵列