Design and performance analysis of reconfigurable modified Vedic multiplier with 3-1-1-2 compressor

摘要

The Fast Fourier Transform (FFT) is a digital signal processing (DSP) function most commonly used one in many applications such as imaging, wireless communication, and multimedia. The FFT processors are consists of butterfly structure operations, which includes multiplication, addition and subtraction of complex value data. In this paper, an FFT butterfly structure is designed using the Vedic multiplier for high speed applications. In this Vedic multiplier, Urdhava Triyakbhyam algorithm is utilized to improve its efficiency. Then, detector block is introduced to identify the unwanted portion of the input data to be processed in the data processing unit. Therefore, data computation time is reduced in the detector based Vedic multiplier that supports full range and half range input data. The detector is developed based on Boolean function, to detect the valid ranges of two input operands during input data computation. The detector result is used to select the operand with half range input data for Vedic multiplication and it is disabled the surplus computation. So, it reduces the switching activities in the logic gates and proportionally reduces the power consumption. The proposed design-I is consists of Vedic algorithm and the detection unit. Then, the 3-1-1-2 compressor is designed and it is utilized in the multiplier. The proposed design-II is developed with modified Vedic algorithm, detection unit and proposed 3-1-1-2 compressor. Finally, the radix-2, radix-4, and radix-8 FFT butterflies are implemented using the detection unit based Vedic multiplier, the 3-1-1-2 compressor based multiplier and various existing multiplier. The proposed design-I and proposed design-II is designed and implemented in Spartan-6, Virtex-4 and Virtex-5 FPGA family devices. The proposed reconfigurable Vedic multiplier is simulated and synthesized using Synopsys tools using the 90 nm standard cell library. (C) 2019 Elsevier B.V. All rights reserved.