A high-performance inner-product processor for real and complex numbers.

A novel, high-performance fixed-point inner-product processor based on a redundant binary number system is investigated in this dissertation. This scheme decreases the number of partial products to 50%, while achieving better speed and area performance, as well as providing pipeline extension opportunities. When modified Booth coding is used, partial products are reduced by almost 75%, thereby significantly reducing the multiplier addition depth. The design is applicable for digital signal and image processing applications that require real and/or complex numbers inner-product arithmetic, such as digital filters, correlation and convolution. This design is well suited for VLSI implementation and can also be embedded as an inner-product core inside a general purpose or DSP FPGA-based processor. Dynamic control of the computing structure permits different computations, such as a variety of inner-product real and complex number computations, parallel multiplication for real and complex numbers, and real and complex number division. The same structure can also be controlled to accept redundant binary number inputs for multiplication and inner-product computations. An improved 2's-complement to redundant binary converter is also presented

Throughput/Area-Efficient Accelerator of Elliptic Curve Point Multiplication over GF(2233) on FPGA

This paper presents a throughput/area-efficient hardware accelerator architecture for elliptic curve point multiplication (ECPM) computation over GF(2233). The throughput of the proposed accelerator design is optimized by reducing the total clock cycles using a bit-parallel Karatsuba modular multiplier. We employ two techniques to minimize the hardware resources: (i) a consolidated arithmetic unit where we combine a single modular adder, multiplier, and square block instead of having multiple modular operators, and (ii) an Itoh–Tsujii inversion algorithm by leveraging the existing hardware resources of the multiplier and square units for multiplicative inverse computation. An efficient finite-state-machine (FSM) controller is implemented to facilitate control functionalities. To evaluate and compare the results of the proposed accelerator architecture against state-of-the-art solutions, a figure-of-merit (FoM) metric in terms of throughput/area is defined. The implementation results after post-place-and-route simulation are reported for reconfigurable field-programmable gate array (FPGA) devices. Particular to Virtex-7 FPGA, the accelerator utilizes 3584 slices, needs 7208 clock cycles, operates on a maximum frequency of 350 MHz, computes one ECPM operation in 20.59 s, and the calculated value of FoM is 13.54. Consequently, the results and comparisons reveal that our accelerator suits applications that demand throughput and area-optimized ECPM implementations

Booth Algorithm with Implementation of UART Module using FPGA

FPGA gives high level of flexibility to the user to rapidly construct and test any hardware. It has a lot of gates which are used depending upon the hardware to be implemented. These project aims at designing Booth multiplier using VHDL for signed bit multiplication in FPGA for high speed operations, developed and implemented of UART module required to enable two-way communication between the DE-2 board and computer. It is also designed GUI interface using MATLAB for sending data and enable the output of the process result to be displayed. The Booth multiplier was implemented using the algorithm in both signed and unsigned number and the input and output of the multiplication was successfully achieved and confirmed through simulation. The GUI was implemented and tested, which UART module also performed well for transmitting and receiving of 8-bit width data. In general, the objective of this project was successfully achieved, which, the result of the component part were able to be tested

High-Speed and Low-Power PID Structures for Embedded Applications.

International audienceIn embedded control applications, control-rate and energyconsumption are two critical design issues. This paper presents a series of highspeed and low-power finite-word-length PID controllers based on a new recursive multiplication algorithm. Compared to published results into the same conditions, savings of 431% and 20% are respectively obtained in terms of control-rate and dynamic power consumption. In addition, the new multiplication algorithm generates scalable PID structures that can be tailored to the desired performance and power budget. All PIDs are implemented at RTL level as technology-independent reusable IP-cores. They are reconfigurable according to two compile-time constants: set-point word-length and latency

New High-Speed and Low-Power radix-2r multiplication algorithms.

International audienceIn this paper, a new recursive multibit recoding multiplication algorithm is introduced. It provides a general space-time partitioning of the multiplication problem that not only enables a drastic reduction of the number of partial products (N/r), but also eliminates the need of pre-computing odd multiples of the multiplicand in higher radix (r≥3) multiplication. Based on a mathematical proof that any higher radix-2r can be recursively derived from a combination of two or a number of lower radices, a series of generalized radix-2r multipliers are generated by means of primary radices: 21, 22, 25, and 28. A variety of higher-radix (23-232) two's complement 64x64 bit serial/parallel multipliers are implemented on Virtex-6 FPGA and characterized in terms of multiply-time, energy consumption per multiply-operation, and area occupation for r value varying from 2 to 64. Compared to a recent published algorithm, savings of 21%, 53%, 105% are respectively obtained in terms of speed, power, and area

An area-optimized N-bit multiplication technique using N/2-bit multiplication algorithm

A unique design for an optimized N-bit multiplier is proposed and implemented which utilizes a modified divide-and-conquer technique. The conventional technique requires four N/2-bit multipliers to perform N-bit multiplication, whereas the proposed design uses only one multiplier module in hardware to perform the functionality of four modules. It uses Dadda algorithm in its multiplier module. It has been implemented using Verilog HDL, and a good accuracy of results was observed in simulations which effectively verify its functionality. Design was also synthesized on various FPGAs including Spartan 3E, Virtex-5 and Virtex-7. Performance summary, after place and route, showed that the proposed approach significantly reduces hardware utilization. Furthermore, the proposed design is almost 75% more efficient in terms of resources utilization and operating frequency as compared to the conventional design

FPGA Implementation & Performance Comparision of Various High Speed unsigned Binary Multipliers using VHDL

Today, most of the DSP computations involve the use of multiply accumulate operations and therefore the design of fast and efficient multipliers is imperative. The addition and multiplication of two binary numbers is the fundamental and most often used arithmetic operation in microprocessors, digital signal processors and data-processing application-specific integrated circuits. In this paper, we present the study of different types of multipliers by comparing the speed and area of each. In this work, VHDL coding and XILINX ISE Simulator is employed to implement multipliers like WTM, Dadda Multiplier, Vedic Multiplier, CSHM, Serial Multiplier and Multipliers using different compressors in Wallace tree architecture. The analysis of this work would be helpful to choose a better multiplier in order to fabricate an efficient system

Multiplierless CSD techniques for high performance FPGA implementation of digital filters.

I leverage FastCSD to develop a new, high performance iterative multiplierless structure based on a novel real-time CSD recoding, so that more zero partial products are introduced. Up to 66.7% zero partial products occur compared to 50% in the traditional modified Booth's recoding. Also, this structure reduces the non-zero partial products to a minimum. As a result, the number of arithmetic operations in the carry-save structure is reduced. Thus, an overall speed-up, as well as low-power consumption can be achieved. Furthermore, because the proposed structure involves real time CSD recoding and does not require a fixed value for the multiplier input to be known a priori, the proposed multiplier can be applied to implement digital filters with non-fixed filter coefficients, such as adaptive filters.My work is based on a dramatic new technique for converting between 2's complement and CSD number systems, and results in high-performance structures that are particularly effective for implementing adaptive systems in reconfigurable logic.My research focus is on two key ideas for improving DSP performance: (1) Develop new high performance, efficient shift-add techniques ("multiplierless") to implement the multiply-add operations without the need for a traditional multiplier structure. (2) There is a growing trend toward design prototyping and even production in FPGAs as opposed to dedicated DSP processors or ASICs; leverage this trend synergistically with the new multiplierless structures to improve performance.Implementation of digital signal processing (DSP) algorithms in hardware, such as field programmable gate arrays (FPGAs), requires a large number of multipliers. Fast, low area multiply-adds have become critical in modern commercial and military DSP applications. In many contemporary real-time DSP and multimedia applications, system performance is severely impacted by the limitations of currently available speed, energy efficiency, and area requirement of an onboard silicon multiplier.I also introduce a new multi-input Canonical Signed Digit (CSD) multiplier unit, which requires fewer shift/add/subtract operations and reduced CSD number conversion overhead compared to existing techniques. This results in reduced power consumption and area requirements in the hardware implementation of DSP algorithms. Furthermore, because all the products are produced simultaneously, the multiplication speed and thus the throughput are improved. The multi-input multiplier unit is applied to implement digital filters with non-fixed filter coefficients, such as adaptive filters. The implementation cost of these digital filters can be further reduced by limiting the wordlength of the input signal with little or no sacrifice to the filter performance, which is confirmed by my simulation results. The proposed multiplier unit can also be applied to other DSP algorithms, such as digital filter banks or matrix and vector multiplications.Finally, the tradeoff between filter order and coefficient length in the design and implementation of high-performance filters in Field Programmable Gate Arrays (FPGAs) is discussed. Non-minimum order FIR filters are designed for implementation using Canonical Signed Digit (CSD) multiplierless implementation techniques. By increasing the filter order, the length of the coefficients can be decreased without reducing the filter performance. Thus, an overall hardware savings can be achieved.Adaptive system implementations require real-time conversion of coefficients to Canonical Signed Digit (CSD) or similar representations to benefit from multiplierless techniques for implementing filters. Multiplierless approaches are used to reduce the hardware and increase the throughput. This dissertation introduces the first non-iterative hardware algorithm to convert 2's complement numbers to their CSD representations (FastCSD) using a fixed number of shift and logic operations. As a result, the power consumption and area requirements required for hardware implementation of DSP algorithms in which the coefficients are not known a priori can be greatly reduced. Because all CSD digits are produced simultaneously, the conversion speed and thus the throughput are improved when compared to overlap-and-scan techniques such as Booth's recoding

Design of approximate overclocked datapath

Embedded applications can often demand stringent latency requirements. While high degrees of parallelism within custom FPGA-based accelerators may help to some extent, it may also be necessary to limit the precision used in the datapath to boost the operating frequency of the implementation. However, by reducing the precision, the engineer introduces quantisation error into the design. In this thesis, we describe an alternative circuit design methodology when considering trade-offs between accuracy, performance and silicon area. We compare two different approaches that could trade accuracy for performance. One is the traditional approach where the precision used in the datapath is limited to meet a target latency. The other is a proposed new approach which simply allows the datapath to operate without timing closure. We demonstrate analytically and experimentally that for many applications it would be preferable to simply overclock the design and accept that timing violations may arise. Since the errors introduced by timing violations occur rarely, they will cause less noise than quantisation errors. Furthermore, we show that conventional forms of computer arithmetic do not fail gracefully when pushed beyond the deterministic clocking region. In this thesis we take a fresh look at Online Arithmetic, originally proposed for digit serial operation, and synthesize unrolled digit parallel online arithmetic operators to allow for graceful degradation. We quantify the impact of timing violations on key arithmetic primitives, and show that substantial performance benefits can be obtained in comparison to binary arithmetic. Since timing errors are caused by long carry chains, these result in errors in least significant digits with online arithmetic, causing less impact than conventional implementations.Open Acces

Hardware Implementation of Efficient Elliptic Curve Scalar Multiplication using Vedic Multiplier

This paper presents an area efficient and high-speed FPGA implementation of scalar multiplication using a Vedic multiplier. Scalar multiplication is the most important operation in Elliptic Curve Cryptography(ECC), which used for public key generation and the performance of ECC greatly depends on it. The scalar multiplication is multiplying integer k with scalar P to compute  Q=kP, where k is private key and P is a base point on the Elliptic curve. The Scalar multiplication underlying finite field arithmetic operation i.e. addition multiplication, squaring and inversion to compute Q. From these finite field operations, multiplication is the most time-consuming operation, occupy more device space and it dominates the speed of Scalar multiplication. This paper presents an efficient implementation of finite field multiplication using a Vedic multiplier.  The scalar multiplier is designed over Galois Binary field GF(2233) for field size=233-bit which is secured curve according to NIST.  The performances of the proposed design are evaluated by comparing it with  Karatsuba based scalar multiplier for area and delay. The results show that the proposed scalar multiplication using Vedic multiplier has consumed 22% less area on FPGA and also has 12% less delay, than Karatsuba, based scalar multiplier. The scalar multiplier is coded in Verilog HDL, synthesize and simulated in Xilinx 13.2 ISE on Virtex6 FPGA