Combined Integer and Floating Point Multiplication Architecture(CIFM) for FPGAs and Its Reversible Logic Implementation

In this paper, the authors propose the idea of a combined integer and floating point multiplier(CIFM) for FPGAs. The authors propose the replacement of existing 18x18 dedicated multipliers in FPGAs with dedicated 24x24 multipliers designed with small 4x4 bit multipliers. It is also proposed that for every dedicated 24x24 bit multiplier block designed with 4x4 bit multipliers, four redundant 4x4 multiplier should be provided to enforce the feature of self repairability (to recover from the faults). In the proposed CIFM reconfigurability at run time is also provided resulting in low power. The major source of motivation for providing the dedicated 24x24 bit multiplier stems from the fact that single precision floating point multiplier requires 24x24 bit integer multiplier for mantissa multiplication. A reconfigurable, self-repairable 24x24 bit multiplier (implemented with 4x4 bit multiply modules) will ideally suit this purpose, making FPGAs more suitable for integer as well floating point operations. A dedicated 4x4 bit multiplier is also proposed in this paper. Moreover, in the recent years, reversible logic has emerged as a promising technology having its applications in low power CMOS, quantum computing, nanotechnology, and optical computing. It is not possible to realize quantum computing without reversible logic. Thus, this paper also paper provides the reversible logic implementation of the proposed CIFM. The reversible CIFM designed and proposed here will form the basis of the completely reversible FPGAs.Comment: Published in the proceedings of the The 49th IEEE International Midwest Symposium on Circuits and Systems (MWSCAS 2006), Puerto Rico, August 2006. Nominated for the Student Paper Award(12 papers are nominated for Student paper Award among all submissions

Design of efficient reversible floating-point arithmetic unit on field programmable gate array platform and its performance analysis

The reversible logic gates are used to improve the power dissipation in modern computer applications. The floating-point numbers with reversible features are added advantage to performing complex algorithms with high-performance computations. This manuscript implements an efficient reversible floating-point arithmetic (RFPA) unit, and its performance metrics are realized in detail. The RFP adder/subtractor (A/S), RFP multiplier, and RFP divider units are designed as a part of the RFP arithmetic unit. The RFPA unit is designed by considering basic reversible gates. The mantissa part of the RFP multiplier is created using a 24x24 Wallace tree multiplier. In contrast, the reciprocal unit of the RFP divider is designed using Newton Raphson’s method. The RFPA unit and its submodules are executed in parallel by utilizing one clock cycle individually. The RFPA unit and its submodules are synthesized separately on the Vivado IDE environment and obtained the implementation results on Artix-7 field programmable gate array (FPGA). The RFPA unit utilizes only 18.44% slice look-up tables (LUTs) by consuming the 0.891 W total power on Artix-7 FPGA. The RFPA unit sub-models are compared with existing approaches with better performance metrics and chip resource utilization improvements

Pipelined vedic multiplier with manifold adder complexity levels

Recently, the increased use of portable devices, has driven the research world to design systems with low power-consumption and high throughput. Vedic multiplier provides least delay even in complex multiplications when compared to other conventional multipliers. In this paper, a 64-bit multiplier is created using the Urdhava Tiryakbhyam sutra in Vedic mathematics. The design of this 64-bit multiplier is implemented in five different ways with the pipelining concept applied at different stages of adder complexities. The different architectures show different delay and power consumption. It is noticed that as complexity of adders in the multipliers reduce, the systems show improved speed and least hardware utilization. The architecture designed using 2 x 2 – bit pipelined Vedic multiplier is, then, compared with existing Vedic multipliers and conventional multipliers and shows least delay

MF-RALU: design of an efficient multi-functional reversible arithmetic and logic unit for processor design on field programmable gate array platform

Most modern computer applications use reversible logic gates to solve power dissipation issues. This manuscript uses an efficient multi-functional reversible arithmetic and logical unit (MF-RALU) to perform 30 operations. The 32-bit MF-RALU includes arithmetic, logical, complement, shifters, multiplexers, different adders, and multipliers. The multi-bit reversible multiplexers are used to construct the MF-RALU structure. The Reduced instruction set computer (RISC) processor is designed to realize the functionality of the MF-RALU. The MF-RALU can perform its operation in a single clock cycle. The 1-bit RALU is developed and compared with existing approaches with improvements in performance metrics. The 32-bit reversible arithmetic units (RAUs) and reversible logical units (RLUs) are constructed using 1-bit RALU. The MF-RALU and RISC processor are synthesized individually in the Vivado environment using Verilog-HDL and implemented on Artix-7 field programmable gate array (FPGA). The MF-RALU utilizes a <11% chip area and consumes 332 mW total power. The RISC processor utilizes a <3% chip area and works at 483 MHZ frequency by consuming 159 mW of total power on Artix-7 FPGA

IMPLEMENTATION OF AN EFFICIENT AND OPTIMIZED VEDIC MULTIPLIER DESIGN USING REVERSIBLE LOGIC GATES

Multiplier design is always a challenging task; however many   designs are proposed, the user needs demands much more optimized ones. Vedic mathematics provides   some   algorithms that evaluate fast results, both in mental calculations or hardware design. Power dissipation is continuously reduced by the use of Reversible logic. The reversible Urdhva Tiryakbhayam Vedic multiplier is one such multiplier which is effective both in terms of speed and power. In this paper the modified design increase the performance by maintain the design functionality without any degradation. The Total Reversible Logic Implementation Cost (TRLIC) evaluate the proposed design. This multiplier has application over  designing Fast Fourier Transforms (FFTs) Filters and other applications of DSP like imaging, software defined radios, wireless communications.

An Estimated Multiplier For Quick Energy-Efficient Digital Indication Dispensation

We propose a high-speed, energy-efficient approximation multiplier. The method is to round the coefficients to the nearest exponent of two. In this way, the abbreviated arithmetic part is omitted from the multiplication process to improve the speed and power consumption with a small error rate. The proposed approach applies to both signed and unsigned complications. We propose that three devices be implemented for the coarse multiplier, which includes one for unsigned and two for signed operations. The efficiency of the proposed multiplier is evaluated by comparing its performance with the performance of some approximate and accurate multipliers using different design criteria. In addition, the effectiveness of the proposed approximate multiplier is studied in two image processing applications, i.e. image sharpening and smoothing

FPGA based efficient Multiplier for Image Processing Applications using Recursive Error Free Mitchell Log Multiplier and KOM Architecture

The Digital Image processing applications like medical imaging, satellite imaging, Biometric trait images etc., rely on multipliers to improve the quality of image. However, existing multiplication techniques introduce errors in the output with consumption of more time, hence error free high speed multipliers has to be designed. In this paper we propose FPGA based Recursive Error Free Mitchell Log Multiplier (REFMLM) for image Filters. The 2x2 error free Mitchell log multiplier is designed with zero error by introducing error correction term is used in higher order Karastuba-Ofman Multiplier (KOM) Architectures. The higher order KOM multipliers is decomposed into number of lower order multipliers using radix 2 till basic multiplier block of order 2x2 which is designed by error free Mitchell log multiplier. The 8x8 REFMLM is tested for Gaussian filter to remove noise in fingerprint image. The Multiplier is synthesized using Spartan 3 FPGA family device XC3S1500-5fg320. It is observed that the performance parameters such as area utilization, speed, error and PSNR are better in the case of proposed architecture compared to existing architecture