Triple-Base Hybrid Joint Sparse Form and its Applications

Multi-scalar multiplication and multi-exponentiation are the major problems in digital signal processing(DSP) and in public-key cryptography. In DSP, multiplication of the filter coefficients, which is used in different signal processing algorithms, is a time consuming operation. Also in elliptic curve cryptography(ECC), this multiplication process takes a lot of time. Though there are several algorithms to speed up this multiplication process, but they are not up to the satisfactory limit. The algorithms are based on the minimization of the multipliers or adders required, i.e. the minimization of the numbers of „one‟ appear in the binary representation of the signal and the coefficients in DSP or of the number of general multiplications and points addition in ECC. Different existing algorithms in this context are Joint Sparse Form(JSF), w-NAF, Double Base Chain(DBC), Hybrid Binery-Ternary Joint Sparse Form(HBTJSF) etc. In this paper, a novel algorithm has been proposed which is the modified HBTJSF, known as Triple-Base Hybrid Joint Sparse Form(TBHJSF). The proposed method is based on the decomposition of an integer or fraction that mixes the power of the base 2,3 and 5. The experimental results show that it requires less numbers of multiplier and adder and hence show its novelty over other algorithms.