International Journal of Engineering Inventions (IJEI) provides a multidisciplinary passage for researchers, managers, professionals, practitioners and students around the globe to publish high quality, peer-reviewed articles on all theoretical and empirical aspects of Engineering and Science.
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16.modul melakukan deployment model (final) v1 1ArdianDwiPraba
Program Digital Talent Scholarship 2021 bertujuan meningkatkan keterampilan 60.000 peserta di bidang teknologi informasi dan komunikasi. Program ini terdiri dari tujuh akademi pelatihan untuk berbagai kelompok sasaran seperti lulusan perguruan tinggi, SMK, guru, dan UMKM.
Dokumen tersebut berisi penjelasan tentang berbagai elemen diagram UML seperti class diagram, use case diagram, activity diagram, dan sequence diagram. Di antaranya adalah penjelasan tentang class, object, attribute, operation, enkapsulasi, actor, use case, control flow, message, lifeline, dan hubungan antar elemen-elemen tersebut.
The document discusses extended relational algebra operations including generalized projection, outer join, and aggregate functions. Generalized projection allows arithmetic functions in the projection list. Outer join computes a join and adds unmatched tuples using null values. Aggregate functions return a single value from a collection and can be used in aggregate operations to group and summarize data. Modification operations like deletion, insertion, and updating are also expressed using relational algebra.
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16.modul melakukan deployment model (final) v1 1ArdianDwiPraba
Program Digital Talent Scholarship 2021 bertujuan meningkatkan keterampilan 60.000 peserta di bidang teknologi informasi dan komunikasi. Program ini terdiri dari tujuh akademi pelatihan untuk berbagai kelompok sasaran seperti lulusan perguruan tinggi, SMK, guru, dan UMKM.
Dokumen tersebut berisi penjelasan tentang berbagai elemen diagram UML seperti class diagram, use case diagram, activity diagram, dan sequence diagram. Di antaranya adalah penjelasan tentang class, object, attribute, operation, enkapsulasi, actor, use case, control flow, message, lifeline, dan hubungan antar elemen-elemen tersebut.
The document discusses extended relational algebra operations including generalized projection, outer join, and aggregate functions. Generalized projection allows arithmetic functions in the projection list. Outer join computes a join and adds unmatched tuples using null values. Aggregate functions return a single value from a collection and can be used in aggregate operations to group and summarize data. Modification operations like deletion, insertion, and updating are also expressed using relational algebra.
The document provides an overview of the relational model and relational algebra used in relational databases. It defines key concepts like relations, tuples, attributes, domains, schemas, instances, keys, and normal forms. It also explains the six basic relational algebra operations - select, project, union, difference, cartesian product, and rename - and how they can be composed to form complex queries. Examples of relations and queries involving operations like selection, projection, joins are provided to illustrate relational algebra.
This document discusses different methods for data modeling XML documents, including DTD, XDR schemas, and XML Schema (XSD). DTD is the oldest technology and is part of the XML specification. XDR schemas are proprietary to Microsoft. XSD is a W3C standard that allows specifying data types and has broader vendor support than XDR. The document provides examples of each and notes advantages and disadvantages of DTDs compared to the other methods.
This S.R.S deals with the basic's of hotel management system.It will show different features with different functionalities.Data Flow diagram is also mentioned With 0 and 1 Level diagram.
This document describes a gym management system project created by David O'Connor. The system allows users to manage members, employees, equipment, and fitness classes. It includes domain classes for each entity, collections to store data, a user interface, and functionality to save and load data. Search and sorting algorithms are implemented. Inheritance is used between the person, member, and employee classes. The system provides options for administrators to add, remove, view, search, and sort data for each entity type through the user interface.
Here you can find 1000's of Multiple Choice Questions(MCQs) of Database Management System(DBMS) includes the MCQs of fundamental of Database Management System(DBMS), introduction of Database Model, Relational Database Model, Constrants, Relational Algebra, Definition and types of Structured Query Language(SQL), Embedded SQL, Database Normalization (1NF, 2NF, 3NF, BCNF, 4NF, 5NF and DKNF) and Data Storage Devices, Architecture of DBMS and Database Security, Integrity and Quality
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DESKRIPSI PERANCANGAN PERANGKAT LUNAK Sistem Akademik Kartu Hasil StudiWindi Widiastuti
Sistem informasi akademik kartu hasil studi (SIAKAD KHS) dirancang untuk mengelola data akademik dan keuangan mahasiswa serta dosen di Universitas Muhammadiyah Malang. Dokumen ini menjelaskan dekomposisi fungsional dan fisik modul sistem, deskripsi layar dan proses, serta matriks keterkaitan antar komponen sistem."
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Survey of Optimization of FFT processor for OFDM Receiversijsrd.com
This document summarizes research on optimizing FFT processors for OFDM receivers. It discusses how FFT/IFFT algorithms are critical components of OFDM systems that require optimization for throughput, area, and power. The document reviews different FFT processor architectures like pipelined and parallel. It proposes a FFT processor with a pipelined architecture and a CORDIC-based ROM-free twiddle factor generator to reduce complexity. Simulation results using MATLAB show the performance of an OFDM receiver with a 512-point FFT. The conclusion is that a pipelined architecture with CORDIC twiddle factor generation optimizes FFT processor performance for OFDM receivers.
Iaetsd pipelined parallel fft architecture through folding transformationIaetsd Iaetsd
This document presents a new VLSI architecture for a real-time pipeline FFT processor using fused floating point operations. It proposes high radix floating point butterflies implemented with two fused operations: a two-term dot product and add-subtract unit. Both discrete and fused radix processors are compared in terms of area. Higher throughput is achieved using a proposed architecture with conflict-free memory access and a new addressing scheme for radix-16 FFT.
The document provides an overview of the relational model and relational algebra used in relational databases. It defines key concepts like relations, tuples, attributes, domains, schemas, instances, keys, and normal forms. It also explains the six basic relational algebra operations - select, project, union, difference, cartesian product, and rename - and how they can be composed to form complex queries. Examples of relations and queries involving operations like selection, projection, joins are provided to illustrate relational algebra.
This document discusses different methods for data modeling XML documents, including DTD, XDR schemas, and XML Schema (XSD). DTD is the oldest technology and is part of the XML specification. XDR schemas are proprietary to Microsoft. XSD is a W3C standard that allows specifying data types and has broader vendor support than XDR. The document provides examples of each and notes advantages and disadvantages of DTDs compared to the other methods.
This S.R.S deals with the basic's of hotel management system.It will show different features with different functionalities.Data Flow diagram is also mentioned With 0 and 1 Level diagram.
This document describes a gym management system project created by David O'Connor. The system allows users to manage members, employees, equipment, and fitness classes. It includes domain classes for each entity, collections to store data, a user interface, and functionality to save and load data. Search and sorting algorithms are implemented. Inheritance is used between the person, member, and employee classes. The system provides options for administrators to add, remove, view, search, and sort data for each entity type through the user interface.
Here you can find 1000's of Multiple Choice Questions(MCQs) of Database Management System(DBMS) includes the MCQs of fundamental of Database Management System(DBMS), introduction of Database Model, Relational Database Model, Constrants, Relational Algebra, Definition and types of Structured Query Language(SQL), Embedded SQL, Database Normalization (1NF, 2NF, 3NF, BCNF, 4NF, 5NF and DKNF) and Data Storage Devices, Architecture of DBMS and Database Security, Integrity and Quality
Thiết kế 1 lượt đồ quan hệ tốt và xấu?
Đánh giá(không theo chuẩn) một lược đồ quan hệ dựa trên tiêu chí:
Ngữ nghĩa của các thuộc tính.
Giảm giá trị trùng lắp trong các bộ.
Giảm giá trị Null trong các bộ.
Không cho phép các bộ dữ liệu sai(không xác định)
Định nghĩa các dạng chuẩn được xem là cách đánh giá(theo chuẩn)
Được giới hạn trên chuẩn của lược đồ quan hệ
DESKRIPSI PERANCANGAN PERANGKAT LUNAK Sistem Akademik Kartu Hasil StudiWindi Widiastuti
Sistem informasi akademik kartu hasil studi (SIAKAD KHS) dirancang untuk mengelola data akademik dan keuangan mahasiswa serta dosen di Universitas Muhammadiyah Malang. Dokumen ini menjelaskan dekomposisi fungsional dan fisik modul sistem, deskripsi layar dan proses, serta matriks keterkaitan antar komponen sistem."
Download luận văn đồ án tốt nghiệp ngành công nghệ thông tin với đề tài: Phân đoạn ảnh dựa trên phương pháp phát hiện biên, cho các bạn làm luận văn tham khảo
Survey of Optimization of FFT processor for OFDM Receiversijsrd.com
This document summarizes research on optimizing FFT processors for OFDM receivers. It discusses how FFT/IFFT algorithms are critical components of OFDM systems that require optimization for throughput, area, and power. The document reviews different FFT processor architectures like pipelined and parallel. It proposes a FFT processor with a pipelined architecture and a CORDIC-based ROM-free twiddle factor generator to reduce complexity. Simulation results using MATLAB show the performance of an OFDM receiver with a 512-point FFT. The conclusion is that a pipelined architecture with CORDIC twiddle factor generation optimizes FFT processor performance for OFDM receivers.
Iaetsd pipelined parallel fft architecture through folding transformationIaetsd Iaetsd
This document presents a new VLSI architecture for a real-time pipeline FFT processor using fused floating point operations. It proposes high radix floating point butterflies implemented with two fused operations: a two-term dot product and add-subtract unit. Both discrete and fused radix processors are compared in terms of area. Higher throughput is achieved using a proposed architecture with conflict-free memory access and a new addressing scheme for radix-16 FFT.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Iaetsd fpga implementation of cordic algorithm for pipelined fft realization andIaetsd Iaetsd
This document discusses using the CORDIC algorithm to implement a pipelined FFT for fingerprint recognition on an FPGA. It proposes a hardware-efficient CORDIC FFT architecture that minimizes computational complexity. The CORDIC algorithm replaces complex multipliers with shift-add operations, providing a simpler hardware implementation than traditional multiplier-based FFT designs. The architecture includes a butterfly structure implemented with CORDIC, an angle generator for twiddle factors, and input/output blocks with registers and multiplexers to enable pipelined processing.
Review on low power high speed 32 point cyclotomic parallel FFT ProcessorIRJET Journal
This document reviews a low-power 32-point cyclotomic parallel fast Fourier transform (FFT) processor. FFT is a technique that efficiently calculates the discrete Fourier transform by reducing the number of operations. Cyclotomic FFT breaks the DFT into several convolutions to reduce the tradeoff between area and performance seen in other FFT algorithms. The paper proposes a design for a 32-point radix-4 FFT using VHDL that combines the advantages of cyclotomic pipelining and parallel multipliers to improve throughput and power efficiency. Previous research on low-power FFT architectures is discussed, focusing on techniques like pipelining, parallel processing, and multiplier-less designs.
High Speed Area Efficient 8-point FFT using Vedic MultiplierIJERA Editor
A high speed fast fourier transform (FFT) design by using three algorithm is presented in this paper. In algorithm 3, 4-bit Vedic multiplier based technique are used in FFT. In this technique used in three 4-bit ripple carry adder and four 2*2 Vedic multiplier. The main parameter of this paper is number of slice, 4-input LUTS and maximum combinational path delay were calculate.
Design of Scalable FFT architecture for Advanced Wireless Communication Stand...IOSRJECE
Now a day’s numerous wireless communication standards have raised additional stringent requirements on each throughput and flexibility for FFT computation. Advanced wireless systems support multiple standards to satisfy the demands of user application necessities. A wireless system whereas supporting multiple standards should also satisfy performance necessities of these supported standards. Meeting performance requirements of multiple standards is a challenge while designing a system. Fast Fourier transformations, a kernel processing task in communication systems, are studied intensively for efficient software and hardware implementations. To design an efficient system, it's necessary to efficiently design its performance critical component. each system must meet stringent design parameters like high speed, low power, low area, low cost, high flexibility and high scalability, designing FFT processor to support multiple wireless standards whereas meeting the above such performance necessities is a difficult task. This paper proposed a highly efficient scalable architecture, software tools design, and design implementation. The reconstruction of the FFT computation flow is design into a scalable structure. The FFT can be easily expanded for any-point FFT computation. The various parameters satisfied the conditions, gives proper and efficient outputs as compare to other platforms.
IRJET - Design and Implementation of FFT using Compressor with XOR Gate TopologyIRJET Journal
This document describes a design for implementing a Fast Fourier Transform (FFT) using an adder compressor with a new XOR gate topology. The goals are to increase power efficiency, reduce logic utilization (LUTs), and decrease time complexity/delay compared to other FFT implementations. An adder compressor is proposed that uses XOR gates to compress 4 input bits into 2 output bits (sum and carry), allowing parallel addition without carry propagation. Simulation results on a Xilinx FPGA show the compressor-based FFT uses fewer LUTs, consumes less power, and has a shorter delay compared to an FFT using a Booth multiplier.
This document presents a new technique for designing an area efficient FFT/IFFT processor for WPAN applications using a Radix-25 algorithm and Wallace tree multiplier. The proposed design reduces the size of the twiddle factor memory and number of complex multiplications compared to previous designs. Simulation results show the proposed design occupies less area (14% of total logic elements) and has lower hardware complexity than prior approaches.
Iaetsd finger print recognition by cordic algorithm and pipelined fftIaetsd Iaetsd
This document proposes an efficient CORDIC pipelined FFT algorithm for fingerprint recognition on FPGAs. The CORDIC algorithm uses only shift and add operations, making it suitable for replacing multipliers in the butterfly operations of an FFT. This reduces computational complexity. The proposed system takes a fingerprint, processes it with the CORDIC pipelined FFT, extracts features which are stored and then matched against a test fingerprint for recognition. The algorithm aims to provide an efficient hardware implementation of FFT and fingerprint recognition using minimal computations.
IRJET- Low Complexity Pipelined FFT Design for High Throughput and Low Densit...IRJET Journal
This document describes a low complexity pipelined FFT design for high throughput applications. It proposes a feedforward FFT architecture based on rotator allocation to reduce the number and complexity of rotators. The key aspects are:
1) It uses a divide-and-conquer approach to split the FFT computation into stages, with butterflies operating on data whose indexes differ in the stage bit position.
2) It allocates the index bits into serial and parallel dimensions to optimize the distribution of rotations across stages. This aims to minimize the number of rotators and keep rotations in the same serial allocation set.
3) The proposed approach is shown to reduce the number and complexity of rotators in the FFT architecture compared
FPGA Implementation of Mixed Radix CORDIC FFTIJSRD
In this Paper, the architecture and FPGA implementation of a Coordinate Rotation Digital Computer (CORDIC) pipeline Fast Fourier Transform (FFT) processor is presented. Fast Fourier Transforms (FFT) is highly efficient algorithm which uses Divide and Conquer approach for speedy calculation of Discrete Fourier transform (DFT) to obtain the frequency spectrum. CORDIC algorithm which is hardware efficient and avoids the use of conventional multiplication and accumulation (MAC) units but evaluates the trigonometric functions by the rotation of a complex vector by means of only add and shift operations. We have developed Fixed point FFT processors using VHDL language for implementation on Field Programmable Gate Array. A Mixed Radix 8 point DIF FFT/IFFT architecture with CORDIC Twiddle factor generation unit with use of pipeline implementation FFT processor has been developed using Xilinx XC3S500E Spartan-3E FPGA and simulated with maximum frequency of 157.359 MHz for 16 bit length 8 point FFT. Results show that the processor uses less number of LUTs and achieves Maximum Frequency.
DESIGN AND VHDL IMPLEMENTATION OF 64-POINT FFT USING TWO STRUCTURE 8-POINT FF...Journal For Research
In this paper, we present a novel fixed-point 32-bit word-width Radix-2 64-point FFT processor. The 64-point FFT is realized by decomposing it into a two-dimensional structure of 8-point FFTs. This approach reduces the number of required complex multiplications compared to the conventional radix-2 64-point FFT algorithm. The complex multiplication operations are realized using shift-and-add operations. Thus, the processor does not use a two-input digital multiplier. It also does not need any RAM or ROM for internal storage of coefficients. The Fast Fourier Transform (FFT) is one of the rudimentary operations in field of digital signal, image processing and FFT processor is a critical block in all multicarrier systems used primarily in the mobile environment. Fast Fourier transform (FFT) is an efficient implementation of the discrete Fourier transform (DFT). FFT blocks are complex to implement and it consumes more resources. So, a efficient technique used here in which FFT is implemented in such a way that it consumes very less resources. This module of 64-point FFT is designed using VHDL programming language. In this work, a pure VHDL design, integrated with some intellectual property (IP) blocks and simulation, synthesis and implementation XILINX ISE 13.2 software is used.
This document discusses optimized implementations of FFT processors for OFDM systems. It describes how FFT and IFFT are important computations for OFDM modulation and demodulation. It proposes an 8-point FFT processor using the radix-2 algorithm and R2MDC architecture. The processor eliminates complex multiplications using shift-and-add operations. It also concludes that the proposed FFT processor designs are suitable for MIMO OFDM standards like IEEE 802.11n and IEEE 802.16 WiMAX.
IRJET- VLSI Architecture for Reversible Radix-2 FFT Algorithm using Programma...IRJET Journal
This document describes the design of a reversible radix-2 FFT algorithm using programmable reversible gates. It begins with background on the discrete Fourier transform and fast Fourier transform. It then discusses previous work using reversible Peres and TR gates. The main contribution is a proposed method for implementing the radix-2 FFT using a reversible DKG gate. Simulation results for 8-point, 16-point and 32-point FFTs are presented, showing the structure was implemented on a Xilinx FPGA. The reversible FFT design reduces power consumption compared to traditional irreversible implementations.
IMPLEMENTATION OF SDC - SDF ARCHITECTURE FOR RADIX-4 FFT VLSICS Design
Very large scale integration and Digital signal processing are the very crucial technologies from the last
few decades. DSP applications require high performance, low area and low power VLSI circuits. This
paper is discussing about FFT which is one of the vital component in the digital signal processing. In this
Paper, we propose a single path delay commutator–feedback (SDC-SDF) Architecture for Radix-4 FFT
and presented its simulation and synthesis results. The Radix-4 FFT architecture consists of log4 N-1 SDC
Stages and 1 SDF stage. Previously, the radix-2 SDC-SDF (Single path delay commutator-feedback) FFT
architecture was includes log2 N-1 SDC Stages and 1 SDF stage. The proposed Radix-4 SDC-SDF
architecture reduces the number of multiplications and additions as well as number of stages which
achieves reduced area and low power. The resultant architecture is simulated using Modelsim, design
verification and synthesis results are done using Xilinx ISE. The proposed architecture is compared with
Radix-2 SDC-SDF FFT and it can achieve less area as well as low power
Implementation of High Throughput Radix-16 FFT ProcessorIJMER
The extension of radix-4 algorithm to radix-16 to achieve the high throughput of 2.59 giga-samples/s for WPAN’s.We are also reformulating radix-16 algorithm to achieve low-complexity and
low area cost and high performance. Radix-16 FFT is obtained by cascaded the radix -4 butterfly
units. It facilitates low-complexity realization of radix-16 butterfly operation and high operation speed
due to its optimized pipelined structure. Besides, a new three-stage multiplier for twiddle factor
multiplication is also proposed, which has lower area and power consumption than conventional
complex multipliers
An Area Efficient Mixed Decimation MDF Architecture for Radix 22 Parallel FFTIRJET Journal
This document describes a proposed area efficient mixed decimation Multipath Delay Feedback (MDF) architecture for radix parallel Fast Fourier Transform (FFT) computation. The proposed architecture aims to improve efficiency in utilization of arithmetic resources in MDF architectures by integrating Decimation-In-Time (DIT) operations into Decimation-In-Frequency (DIF) operated computing units. This activates idle periods of arithmetic units in MDF architectures. The proposed architecture, called a mixed decimation MDF or DF architecture, is compared theoretically and experimentally to conventional MDF architectures. Results show the proposed DF architecture achieves improved efficiency in consumption of arithmetic resources.
The document describes a modified radix-24 single-data-path discrete Fourier transform (DFT) algorithm and architecture for implementing a 128-point inverse fast Fourier transform (IFFT) module for use in FPGA-based multiband orthogonal frequency division multiplexing (MB-OFDM) ultra-wideband (UWB) systems. The key aspects of the proposed design include:
1) A modified radix-24 single-data-flow (SDF) DFT algorithm that reorders the twiddle factor sequence to enable easier implementation of complex multiplication compared to earlier designs.
2) A single-data-path pipelined architecture that achieves the required 528 MHz processing speed for the U
IRJET- Review Paper on Radix-2 DIT Fast Fourier Transform using Reversible GateIRJET Journal
1) The document discusses a review paper on implementing a radix-2 Decimation-In-Time (DIT) Fast Fourier Transform (FFT) using reversible DKG gates.
2) The proposed design uses a 4x4 reversible DKG gate that functions as both an adder and subtractor.
3) The design is synthesized using Xilinx ISE software and simulated using VHDL test benches to evaluate performance.
Similar to Design Radix-4 64-Point Pipeline FFT/IFFT Processor for Wireless Application (20)
This document discusses the impact of data mining on business intelligence. It begins by defining business intelligence as using new technologies to quickly respond to changes in the business environment. Data mining is an important part of the business intelligence lifecycle, which includes determining requirements, collecting and analyzing data, generating reports, and measuring performance. Data mining allows businesses to access real-time, accurate data from multiple sources to improve decision making. Using business intelligence and data mining techniques can help businesses become more efficient and make better decisions to increase profits and customer satisfaction. The expected results of applying business intelligence include improved decision making through accurate, timely information to support organizational goals and strategic plans.
This document presents a novel technique for solving the transcendental equations of selective harmonics elimination pulse width modulation (SHEPWM) inverters based on the secant method. The proposed algorithm uses the secant method to simplify the numerical solution of the nonlinear equations and solve them faster compared to other methods. Simulation results validate that the proposed method accurately estimates the switching angles to eliminate specific harmonics from the output voltage waveform and achieves near sinusoidal output current for various modulation indices and numbers of harmonics eliminated.
This document summarizes a research paper that designed and implemented a dual tone multi-frequency (DTMF) based GSM-controlled car security system. The system uses a DTMF decoder and GSM module to allow a car to be remotely controlled and secured from a mobile phone. It works by sending DTMF tones from the phone through calls to the GSM module in the car. The decoder interprets the tones and a microcontroller executes commands to disable the ignition or control other devices. The system was created to improve car security and accessibility through remote monitoring and control with DTMF and GSM technology.
This document presents an algorithm for imperceptibly embedding a DNA-encoded watermark into a color image for authentication purposes. It applies a multi-resolution discrete wavelet transform to decompose the image. The watermark, encoded into DNA nucleotides, is then embedded into the third-level wavelet coefficients through a quantization process. Specifically, the watermark nucleotides are complemented and used to quantize coefficients in the middle frequency band, modifying the coefficients. The watermarked image is reconstructed through inverse wavelet transform. Extraction reverses these steps to recover the watermark without the original image. The algorithm aims to balance imperceptibility and robustness through this wavelet-based, blind watermarking scheme.
1) The document analyzes the dynamic saturation point of a deep-water channel in Shanghai port based on actual traffic data and a ship domain model.
2) A dynamic channel transit capacity model is established that considers factors like channel width, ship density, speed, and reductions due to traffic conditions.
3) Based on AIS data from the channel, the average traffic flow is calculated to be 15.7 ships per hour, resulting in a dynamic saturation of 32.5%, or 43.3% accounting for uneven day/night traffic volumes.
The document summarizes research on the use of earth air tunnels and wind towers as passive solar techniques. Key findings include:
- Earth air tunnels circulate air through underground pipes to take advantage of the stable temperature 4 meters below ground for cooling in summer and heating in winter. Testing showed the technique can reduce ambient temperatures by up to 14 degrees Celsius.
- Wind towers circulate air through tall shafts to cool air entering buildings at night and provide downward airflow of cooled air during the day.
- Experimental testing of an earth air tunnel system over multiple months found maximum temperature reductions of 33% in spring and minimum reductions of 15% in summer.
The document compares the mechanical and physical properties of low density polyethylene (LDPE) thin films and sheets reinforced with graphene nanoparticles. LDPE/graphene thin films were produced via solution casting, while sheets were made by compression molding. Testing showed that the thin films had enhanced tensile strength, lower melt flow index, and higher thermal stability compared to sheets. The tensile strength of thin films increased by up to 160% with 1% graphene, while sheets increased by 70%. Melt flow index decreased more for thin films, indicating higher viscosity. Thin films also showed greater improvement in glass transition temperature. These results demonstrate that processing technique affects the properties of LDPE/graphene nanocomposites.
The document describes improvements made to a friction testing machine. A stepper motor and PLC control system were added to automatically vary the load on friction pairs, replacing the manual method. Tests using the improved machine found that the friction coefficient decreases as the load increases, and that abrasive and adhesive wear increased with higher loads. The improved machine allows more accurate and convenient testing of friction pairs under varying load conditions.
This document summarizes a research article that investigates the steady, two-dimensional Falkner-Skan boundary layer flow over a stationary wedge with momentum and thermal slip boundary conditions. The flow considers a temperature-dependent thermal conductivity in the presence of a porous medium and viscous dissipation. Governing partial differential equations are non-dimensionalized and transformed into ordinary differential equations using similarity transformations. The equations are highly nonlinear and cannot be solved analytically, so a numerical solver is used. Numerical results are presented for the skin friction coefficient, local Nusselt number, velocity and temperature profiles for varying parameters like the Falkner-Skan parameter and Eckert number.
An improvised white board compass was designed and developed to enhance the teaching of geometrical construction concepts in basic technology courses. The compass allows teachers to visually demonstrate geometric concepts and constructions on a white board in an engaging, hands-on manner. It supports constructivist learning principles by enabling students to observe and emulate the teacher. The design process utilized design and development research methodology to test educational theories and validate the practical application of the compass. The improvised compass was found to effectively engage students and improve their performance in learning geometric constructions.
The document describes the design of an energy meter that calculates energy using a one second logic for improved accuracy. The meter samples voltage and current values using an ADC synchronized to the line frequency via PLL. It calculates active and reactive power by averaging the sampled values over each second. The accumulated active power for each second is multiplied by one second to calculate energy, which is accumulated and converted to kWh. Test results showed the meter achieved an error of 0.3%, within the acceptable limit for class 1 meters. Considering energy over longer durations like one second helps reduce percentage error in the calculation.
This document presents a two-stage method for solving fuzzy transportation problems where the costs, supplies, and demands are represented by symmetric trapezoidal fuzzy numbers. In the first stage, the problem is solved to satisfy minimum demand requirements. Remaining supplies are then distributed in the second stage to further minimize costs. A numerical example demonstrates using robust ranking techniques to convert the fuzzy problem into a crisp one, which is then solved using a zero suffix method. The total optimal costs from both stages provide the solution to the original fuzzy transportation problem.
1) The document proposes using an Adaptive Neuro-Fuzzy Inference System (ANFIS) controller for a Distributed Power Flow Controller (DPFC) to improve voltage regulation and power quality in a transmission system.
2) A DPFC is placed at a load bus in an IEEE 4 bus system and its performance is compared using a PI controller and ANFIS controller.
3) Simulation results show the ANFIS controller provides faster convergence and better voltage profile maintenance during voltage sags and swells compared to the PI controller.
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Design Radix-4 64-Point Pipeline FFT/IFFT Processor for Wireless Application
1. International Journal of Engineering Inventions
e-ISSN: 2278-7461, p-ISSN: 2319-6491
Volume 3, Issue 2 (September 2013) PP: 67-70
www.ijeijournal.com Page | 67
Design Radix-4 64-Point Pipeline FFT/IFFT Processor for
Wireless Application
*Kandhi srikanth, **S.V.P Subba Rao
*P.G Scholar, Sreenidhi Institute of Technology, and Science
**Associate Professor, Sreenidhi Institute of Technology and Science
ABSTRACT: 4G and other wireless systems are currently hot topics of research and development in the
communication field. Broadband wireless systems based on orthogonal frequency division multiplexing
(OFDM) often require an inverse fast Fourier transform (IFFT) to produce multiple sub-carriers. Fast Fourier
transform (FFT) processing is one of the key procedures in popular orthogonal frequency division multiplexing
(OFDM) communication systems. Our proposed design is aimed to Eliminate the read-only memories (ROM’s)
used to store the twiddle factors, which requires more memory and also increases chip area and to reduce the
number of computations to in order to speed up FFT computation. To remove the read only memories (ROM's)
used to store the twiddle factors, our proposed architecture applies various periodicity properties of twiddle
factors and reconfigurable multiplier. To reuse the same hardware core for reducing the chip area we
implemented single hardware core to perform both FFT and IFFT by adding few extra computations. We
implement the processor in SDF architecture with radix-4 algorithm. There are various algorithms to implement
FFT, such as radix-2, radix-4 and split-radix with arbitrary sizes .Radix-2 algorithm is the simplest one, but its
calculation of addition and multiplication is more than radix-4's. The proposed architecture is compared with
the existing architecture for wireless applications based on performance metrics like power consumption, chip
area, speed etc.
Key words: FFT, IFFT, , OFDM, pipeline,Radix-4.
I. INTRODUCTION
The Fast Fourier Transform (FFT) and its Inverse Fast Fourier Transform (IFFT) are essential in the
field of digital signal processing (DSP), widely used in communication systems, especially in orthogonal
frequency division multiplexing(OFDM) systems, wireless-LAN, ADSL, VDSL systems and WIMAX . Apart
from the applications, the system demands high speed of operation, efficient area and low power consumption,
By considering these facts, we proposed the processor with single path delay feedback (SDF) pipeline
architecture. The SDF pipelined architecture is used for the high-throughput in FFT processor. There are three
types of pipeline structures; they are single-path delay feedback (SDF), single-path delay commutator (SDC)
and multi-path delay commutator. The advantages of single-path delay feedback (SDF) are (1) This SDF
architecture is very simple to implement the different length FFT. (2) The required registers in SDF architecture
is less than MDC and SDC architectures. (3) The control unit of SDF architecture is easier.
We implement the processor in SDF architecture with radix-4 algorithm. There are various algorithms
to implement FFT, such as radix-2, radix-4 and split-radix with arbitrary sizes [3]-[5]. Radix-2 algorithm is the
simplest one, but its calculation of addition and multiplication is more than radix-4's. Though being more
efficient than radix-2, radix-4 only can process 4n-point FFT. The radix-4 FFT equation essentially combines
two stages of a radix-2 FFT into one, so that half as many stages are required. Since the radix-4 FFT requires
fewer stages and butterflies than the radix 2 FFT, the computations of FFT can be further improved
In order to speed up the FFT computation we increase the radix, for reducing the chip size we use
ROM-less architecture and for further low power consumption we implement the reconfigurable complex
multiplier and delay line buffers[8]-[10]. Finally, this paper is organized as follows. Section II describes the
FFT/IFFT processor with radix- 4 algorithm. Proposed architecture is discussed in Section III. Finally
conclusion and future work will see in Section IV.
II. SECTION II. FFT/IFFT ALGORITHM
The fast Fourier transform (FFT) [5] was developed to efficiently speed up its computation time and
significantly reduce the hardware cost. Generally, FFT analyzes an input signal sequence by using decimation-
in-frequency (DIF) or decimation-in-time (DIT) decomposition to construct an efficiently computational signal-
flow graph (SFG). Here, our work employs DIF decomposition because it matches the manipulation manner of
single-path delay pipeline facility.
2. Design Radix-4 64-Point Pipeline FFT/IFFT Processor for Wireless Application
www.ijeijournal.com Page | 68
In order to improve the power reduction, we propose a radix-4 64-point pipeline FFT/IFFT processor.
The radix-4 FFT algorithm is most popular and has the potential to satisfy the current need. The radix-4 FFT
equation essentially combines two stages of a radix-2 FFT into one, so that half as many stages are required. To
calculate 16-point FFT, the radix-2 takes log216=4 stages but the radix-4 takes only log416=2stages. A 16-point,
radix-4 decimation-in-frequency FFT algorithm is shown in Figure 1. Here, our work employs DIF
decomposition because it matches the manipulation manner of single-path delay pipeline facility
Fig.1: Flow graph of a 16-point radix-4 FFT algorithm
III. PROPOSED ARCHITECTURE
The inverse discrete Fourier transform (IDFT) of length N is given by:
, (1)
To reuse the same hardware core for reducing the chip area above equation can be rewrite as:
, (2)
Where the star symbol * denotes a conjugate. This new form can be viewed as a general DFT. In other
words, DFT and IDFT can reuse the same hardware core, while IDFT requires some extra computations. These
extra computations include conjugating the input data Xk and the outcomes of DFT, as well as dividing the
previous output by N. Obviously, this new reuse version of DFT/IDFT algorithm will also simplify the design
effort of an DFT/ IDFT processor and thus reduce the chip area, if both the DFT and IDFT processors are
activated alternatively, and not simultaneously.
Traditional hardware implementation of FFT/IFFT processors usually employs a ROM to look up the
wanted twiddle factors, and then word length complex multipliers to perform FFT computing. However, this
introduces more hardware cost, thus a bit-parallel complex constant multiplication scheme [8]-[11], [14]-[18] is
used to improve the foregoing issue. Besides, since the twiddle factors have a symmetric property, the complex
multiplications used in FFT computation can be one of the following three operation types:
. (b - j a) N/4<k<N/2 (3)
. (a + j b) N/2<k<3N/4 (4)
.(b - j a) 3N/4<k<N (5)
Given the above three equations, any twiddle factor can be obtained by a combination of these twiddle-
factor primary elements. In other words, arbitrary twiddle factor used in FFT can utilize these operation types to
derive the wanted value, thus can significantly shorten the size of ROM used to store the twiddle factors.
Moreover, for hardware implementation consideration, we add two extra operation types to further decrease the
size of ROM. Our method can also prune away. Based on the above operation types above, the 49 complex
3. Design Radix-4 64-Point Pipeline FFT/IFFT Processor for Wireless Application
www.ijeijournal.com Page | 69
multiplications after the third butterfly stage for 64-point FFT will be reduced to the computation of 16 primary
elements. Clearly, this results in the twiddle-factor ROM table to be shrunk significantly.
Radix-4 Single- path Delay Feedback (Fig. 2) uses the registers more efficiently by storing one output
of each butterfly in feedback shift registers. A single data stream goes through the multiplier at every stage. It
has same number of butterfly units and multipliers as in R2MDC approach, but with reduced memory
requirement (N – 1) registers. Its data throughput is (1/x) times that of the corresponding Rx MDC architecture.
The lower area requirement for this structure compared to MDC structures is to its advantage.
Fig .2 64 point Radix-4 single path delay feedback architecture.
Reconfigurable Complex constant Multipliers:
Based on equations (3)-(5), a reconfigurable low-complexity complex constant multiplier for
computing Wi
64 is proposed, as shown in Fig. 3.
Fig.3 Complex multiplier used in proposed architecture.
This structure of this complex multiplier also adopts a cascaded scheme to achieve low-cost hardware.
Here, the meaning of two input signals (I in and I out) and two output signals (Q in and Q out) are the output of
butterfly stages.
In many DFT computations, both complex multiplications and real multiplications are required. For the
purpose of comparison, the counting is based on the number of real multiplications. A complex multiplication
can be realized directly with 4 real multiplications and 2 real additions. With a simple transformation, the
number of real multiplications can be reduced to 3, but the number of real additions increases to 3.We considers
a complex multiplication as 3 real multiplications and 3 real additions in complex multiplier shown above.
IV. CONCLUSION
A novel ROM-less and low-power pipeline 64-point FFT/IFFT processor for OFDM application has
been described in this paper. Considering the symmetric property of twiddle factors in FFT, we have designed a
reconfigurable complex constant multiplier such that the size of twiddle- factor ROM is significantly shrunk,
4. Design Radix-4 64-Point Pipeline FFT/IFFT Processor for Wireless Application
www.ijeijournal.com Page | 70
especially no ROM is needed in our work. Our design takes 3365 slices when synthesized selecting the device
xilinx 3s500e. Of course, our proposed scheme can also be adapted to high-point FFT applications, with a lower
size of twiddle-factor ROM’s. So our design is relatively low cost .it can serve as a powerful FFT/IFFT
processor in many other wireless communication systems.
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