iosr-JVSP   Volume-11 ~ Issue-2 ~ Mar. - Apr. 2021

ABSTRACT: The processors used in the electronic devices spend more time on multiplication operation compared to other arithmetic operations like addition and subtraction. Generally, multiplying two numbers includes basic shift and add operations which are used in Array multipliers. To speed up the multiplication process Conventional Wallace Tree Multiplier (WTM) is used, which is pipelined process and uses carry save adders to decrease the delay. To further increase the speed of the WTM, higher order compressors like 3-2, 4-2, 5-2, 7-2 etc., are used. In this paper we are designing an 8-bit Wallace Multiplier which uses an optimized 4-2 compressor circuit to decrease the power and delay of the multiplier. The design and simulation of the multiplier circuit is done on Tanner EDA tool version 16.0

Key Words: WTM, Compressor, PPG, PPR, DSP's, HA, FA

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ABSTRACT: In this work, the well-known Kramers–Kronig (K-K) relation is reviewed in the context of the frequency domain response function of a linear and causal medium. K-K relation is a bidirectional mathematical expression which relates the real and imaginary parts of a given complex function analytic in the upper half plane. The Fourier integral can be applied to the complete frequency response of a physical system to yield a causal time-domain impulse response. The frequency response of the system being invariant is described under the Hilbert
transform. One of the pairs of the K-K relation expresses the real part of a complex function in terms of an infinite integral involving the imaginary part. The resulting real part of the K-K is a singular function and
requires a careful evaluation. Fast........

Keywords: K-K relation, FFT, Oscillator model, Optical spectroscopy, Hilbert transform

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