Vol 8 Issue 4 October 2020-December 2020

Abstract: Orthogonal Frequency Division Multiplexing (OFDM) is a form of multicarrier modulation Technique. In this System orthogonally placed subcarriers are used to carry the data from transmitter end to receiver end and has found its way to the high speed wireless and mobile communication world. It has excellent immunity against fading and ISI but its major drawback is peak to average power reduction (PAPR) of the transmitted signal. So many methods are proposed to reduce large PAPR. But most of the techniques are complex. In this paper various optimization technique GA, PSO, Hybrid algorithms are proposed to optimize phase factors in PTS technique of OFDM system. The simulation Results of proposed algorithms are compared with OFDM Results.

Keywords: GA, OFDM, PSO, PTS, PAPR.

Title: REDUCTION OF PAPR IN ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING SYSTEM USING OPTIMIZATION METHODS

Author: K. Phani Rama Krishna, Md.Habibulla

International Journal of Electrical and Electronics Research  

ISSN 2348-6988 (online)

Research Publish Journals

Abstract: This paper examines the Bit Error Rate (BER) performance of Multi-user Direct Sequence Multi-Carrier Code Division Multiple Access (DS/MC-CDMA) using spreading codes in fading channels. Multi-Carrier Code Division Multiple Access (MC-CDMA) system operating over frequency selective, slowly fading channels is considered and its performance is studied analytically and by computer simulations. We consider the downlink of a cellular radio system where for each user a BPSK modulation is used. The spreading codes are arranged in a way that reduces the effect of the multipath fading channel and restores some of the orthogonality losses between users. The obtained results show considerable performance improvement compared to conventional OFDM and to MC-CDMA that uses single spreading codes. Moreover, the spreading codes chosen by the method are in a consistent sequence. Using this code selection method, the system capacity of MU-MC-CDMA can be effectively increased without increasing too much system complexity. Simulation results show that the presented method can work well for fading channels.

Keywords:  BPSK, DS/MC-CDMA, Walsh codes, Gold codes, PN Sequence.

Title: BER PERFORMANCE OF MULTI-USER MC-DS-CDMA USING SPREADING CODES IN FADING CHANNELS

Author: TATA BALAJI, J.RAVINDRABABU

International Journal of Electrical and Electronics Research  

ISSN 2348-6988 (online)

Research Publish Journals

Abstract: Fundamental to Saudi Vision 2030 is to maximize the potential of renewable energy. This can be achieved by enhancing the regulatory framework that allows the private sector to buy and invest in the renewable energy industry. The presence of many energy providers into a grid could present a loophole for cyberattacks and reduce the power system’s reliability. A very efficient scheme for proper energy transactions is the adoption of blockchain for decentralizing power generation. The blockchain transactions eliminate the need for a third party and provide a secure and cost-effective meter to cash processes. This article will present successful case studies for implementing the blockchain power exchange, provide a feasibility study, and suggest a framework for the implementation of such a technology in Saudi Arabia.

Keywords: Blockchain, Cryptocurrency, Cybersecurity, Energy Transactions, Microgrid, Smart Grid, Smart Contracts, Tariff, distributed ledgers, Ethereum.

Title: Blockchain-based Energy Trading for Decentralized Energy Generation

Author: Tariq K. Aldawsari, Tariq A. Alateeq, Mohammed A. Alhulayyil, Sultan A. Almansour

International Journal of Electrical and Electronics Research  

ISSN 2348-6988 (online)

Research Publish Journals

Abstract: Fossil fuel, especially crude oil and gas has dominated the global energy mix since World War II, and with it comes the challenges of global warming from greenhouse gases emissions, non-renewable and depleting resources, price hike of crude oil, and environmental pollution, all of which are key factors that have led to the quest for alternative energy sources. Some of the reliable alternative energy sources capable of replacing fuels include water, solar and wind energy, and biofuels, even though fossil fuel still constitutes about  86% of the total global energy consumed  and close to a 100% utility in the transportation sector.  In all these renewable sources, biodiesel has been identified as one of the most suitable replacement of fossil fuel in the transportation and power sectors. To achieve this energy transition, require efficient separation processes and techniques that will produce not only cost-effective fuels, but products that can also reduce the emission of greenhouse gases into the atmosphere. The paper noted that as environmental regulations become increasingly stringent, the costs associated with waste management are expected to rise, and therefore by reducing these costs, separation technologies can contribute to the competitiveness of any industrial economy. The paper further noted that less optimized separation processes are energy intensive coupled with creation of products that are hazardous to the environment and human health. Such systems are also very capital intensive and thus affect the redistribution of available resources to other growth sectors of the economy. This paper therefore reviewed the application of advanced separation techniques in biodiesel production and purification such as equilibrium based, affinity based, solid-liquid, and membrane based separation techniques, and noted that, the low energy intensive, but low quality membrane technology is preferred, and therefore has attracted further scientific and engineering investigation to improve its selectivity, throughput, capacity in order to provide the needed alternative systems to the high energy, high cost, but high quality distillation process, that currently handles fossil fuel used mostly in the transport system.

Keywords: Renewable Energy, Separation Processes and techniques, biofuel, membrane techniques, pollutants.

Title: APPLICATION OF ADVANCED SEPARATION TECHNIQUES IN BIODIESEL PRODUCTION AND PURIFICATION

Author: AMIEYEOFORI VALENTINE FELIX

International Journal of Electrical and Electronics Research  

ISSN 2348-6988 (online)

Research Publish Journals

Abstract: Quantum-dot cellular automata are one of the best alternative technologies of CMOS at nano-scale. It is an emerging technology promising to design circuits with low power consumption, high density as well as high speed. Nanotechnology based QCA basic logic layouts work well while simulating on QCA Designer software. The full adder circuit is a basic unit in digital arithmetic and logic circuits. The design of adders has been reported by various researchers and most of the circuit combinations produce excellent results on simulation. We will understand in this paper to different type of full adder design and formulation to design it. We also try to design QCA full adder design using a different formula for sum and carry which is enhanced in term of cell numbers in comparison to other approaches Although design of QCA full adders has been reported by a large number of researchers but the simulation results on most of the circuits fail to produce claimed outputs as such the carry forward work is becoming difficult. There are certain difficulties in producing desired simulation results while joining two half adders to design full adder. The main cause for the problem seems to be the mismatch of input data, when earlier stage data is combined with the forward stage.

We are study and try to design our own circuitry to overcome issue on complex relation for designing a full adder with two half adder policy rather than we try to separate structure for full adder circuitry to improvise the desired result and minimum requirement of quantum cells. For This purpose we allow to choose different methodology and design techniques.  We have tried to study some full adder designs on the basis of simulation results to move forward with our own designs for the purpose.  

Keywords: Quantum Dot Cellular Automata, Nano Technology’ QCA full adder, QCADesigner.

Title: SURVEY ON 1-BIT FULL ADDER DESIGN IN QUANTUM DOT CELLULAR AUTOMATA

Author: Ritu Shivhare

International Journal of Electrical and Electronics Research  

ISSN 2348-6988 (online)

Research Publish Journals