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Future Wireless Communication Networks: Prospects and Challenges
--R K Chaurasia, A K Saini, V Mathur and R Mukherji
The paper deals with the current scenario and future prospects of the 5G system along with the challenges it faces. The fourth-generation wireless communication systems are already implemented or going to be implemented in many countries. However, there are still some challenges facing 4G, such as spectrum problem, power consumption and poor coverages. Mobile phones are moving faster to provide the user the same or even better experience than the personal computer. It is expected that from mobile communication point of view, we should have a higher data transmission rate compared to wire line network. Also, the expectation is for seamless connectivity and access. The wireless designers have started research on fifth-generation wireless systems that are expected to be deployed after 2020. In this paper, various promising technologies for future wireless communication system such as huge multiple input and multiple output system, power efficient communications and cognitive radio network are discussed. Existing and future challenges are also discussed.
© 2016 IUP. All Rights Reserved.
Network Technology Trend for Next-Generation Wireless Communication
--Subrat Kumar Sethi and Saswati Paramita
The high-rise demand for wireless communication and its customized services has experienced tremendous growth over the last decades. This growth is expected to continue relentlessly with addition of more traffic load as signaling storms. This consumes a significant amount of network resources, compromising network throughput and efficiency, and even in some cases, it may collapse the whole network for a particular period. Nowadays, even new necessities are coming up, besides impending new challenges like lower burden of operation and management pertaining to Device-to-Device (D2D) communications and new social network dynamics. In this scenario, huge investment is required to change/ upgrade the existing wireless communication networks. Taking into account the new priority of requisites, it is pertinent to expect that some network demands can be realized by new network technology based on the current research activities which are continuously enhanced in parallel with user trends and technology developments, and it is also anticipated that such new architecture could be the foundation of networks of the future. Therefore, this paper highlights the requirement and expectations of next-generation network technology.
© 2016 IUP. All Rights Reserved.
Location Prediction Using Legendre Technique for Wireless Network
--S Parija, P K Sahu and S S Singh
In this paper, an Artificial Neural Network (ANN) structure using Multi-Layer Perceptron with Back Propagation (MLP-BP) and Legendre Neural Network (LeNN) applied to location management problem in the cellular system is proposed. The nonlinear Neural Network (NN) that is computationally-efficient solves the issues associated with location management. A large amount of computational time for learning in the case of feed-forward NN such as Back Propagation (BP) is a major issue. The proposed LeNN, basically a single layer structure in which nonlinearity is introduced where the input pattern is enhanced with nonlinear functional expansion, is simpler than MLP-BP. The novelty of the proposed work is: less computational time is required in LeNN than in MLP-BP. The simulation results show that LeNN outperforms the other proposed two techniques on performance error. Using simulation, the effectiveness of subscriber prediction is evaluated. It is also shown that the proposed network is computationally cheap and gives better classification accuracy than MLP classifier.
© 2016 IUP. All Rights Reserved.
Cross-Layer Design in Wireless Sensor Network: A Review
--Rakesh Kumar Saini, Ritika and Sandip Vijay
In Wireless Sensor Network (WSN), nodes are limited in mobility, energy resources, computational capacity and memory. When these extreme limitations are combined with strict traditional architecture, both the network performance and lifetime are compromised by consuming more amount of energy. Network lifetime is the fundamental concern of WSN due to the fact that each node in network operates with extremely limited energy. Recent research has shown that the Open System Interconnection (OSI) model is not necessarily the correct approach for WSN. Researchers have made modifications to communication protocols which violate the OSI model, but achieve specific optimization goals. These modifications are termed as Cross-Layer Design (CLD). CLD allows direct communication between protocols at nonadjacent layers or sharing variables between layers. This paper presents a detailed investigation of CLD and discusses different cross-layer proposals given by researchers.
© 2016 IUP. All Rights Reserved.
Experimental Studies on Microstrip Patch Antenna with Superstrate
--V Saidulu and K Srinivasa Rao
The paper describes the effect of with and without dielectric superstrates on bandwidth, beamwidth, gain, resonant frequency, input impedance, return loss, Voltage Standing Wave Ratio (VSWR) and radiation pattern of rectangular microstrip patch antenna. It is found that there is a slight degradation in the performance of the antenna when the superstrate is touching the patch antenna. In particular, the resonant frequency decreases with increase in the dielectric constant of the superstrate thickness. In addition, it has also been observed that return loss and VSWR increase, however, bandwidth and gain decrease with the dielectric constant of the superstrate thickness. The microstrip patch antenna without dielectric superstrate achieves an impedance bandwidth of 0.203 GHz (SWR < 2) at 2.4 GHz, compared to microstrip patch antenna with dielectric superstrate, which shows that the resonate frequency is decreased to 2.31 GHz from 2.40 GHz, impedance bandwidth to 0.040 GHz from 0.200 GHz (SWR < 2) at 2.30 GHz and the gain to 2.80 GHz from 7.30 GHz. The optimum gain is obtained at r2 = 2.2. This type of antenna is mainly used in wireless and Bluetooth applications.
© 2016 IUP. All Rights Reserved.
A Microstrip Patch Antenna and T-Shaped Slot for X-Band Application
--Archana Negi, Brajlata Chauhan and Sandip Vijay
The paper presents the design of a microstrip patch antenna having ? and T-shaped slot connected to each other. The proposed antenna is printed on FR4 substrate having dielectric constant of 4.3 and thickness of 1.6 mm that can operate on band 8.357 GHz, 10.97 GHz and 13.154 GHz. The structure was simulated through CST microwave studio. All the simulated parameters like return loss, directivity, gain and radiation pattern in 2D/3D for port one and port two are presented.
© 2016 IUP. All Rights Reserved.
Design and Analysis of Electromagnetic Band Gap (EBG)
Square Notch Rectangular Microstrip Antenna
for Dual Frequency Using IE3D
--Virendra Kumar and Sandip Vijay
Rectangular Microstrip Antenna (RMA) with square notch at its center is designed with an infinite ground and studied for its dual frequency characteristics. A microstrip antenna in its simplest configuration consists of a radiating patch on one side of a dielectric substrate (€r) and a ground plane on the other side. In this paper, substrate (FR4) of permittivity of 4.4 and thickness of 1.6 mm and rectangular patch having dimension of 25.5 33.2 mm are used to fabricate microstrip antenna. However, this configuration has a disadvantage—surface waves are formed which reduces the efficiency and gain of RMA. An Electromagnetic Band Gap (EBG) structure is introduced on the other side of substrate which acts as ground plane to suppress the surface wave excited by radiating patch, resulting in the enhancement of gain and efficiency of antenna, named as EBGRMA. For making EBG structure, RMA is modified by etching five columns of holes of dimension 4 4 mm on the bottom ground side of patch which has dimension 63.75 83 mm. The five columns of square hole have center-to-center distance of 8 mm making up an equivalent EBG structure. Later, a metallic reflector is placed at a distance of 8.5 mm below the bottom side of substrate so that power is reflected and thereby increases the gain and directivity of EBGRMA. Patch is fed by a probe at a coordinate of 4.5 and 5.2 mm. The resonant frequency selected for this research is 2.4 GHz.
© 2016 IUP. All Rights Reserved.
An Analysis of Sample Matrix Algorithm for Smart Antenna Applications
--V Ayyem Pillai, K Sri Chandana and G V Subba Reddy
An antenna array consists of distributed antenna elements whose outputs are combined in such a way that the parameters of communication system are optimized. A smart antenna is an antenna array system aided by some “smart” algorithms designed to adapt to different signal environments. Through beamforming, smart antennas offer low co-channel interference and large antenna gain to the desired signal, leading to better performance than conventional antenna systems. Since beamforming is performed in software, forming several beams with the same array is possible by simply reusing the array output. The signal received at each antenna element is multiplied by an optimum weight and these products are added to get the desired output signal. The weight vector can be calculated using one of the many adaptive algorithms such as Least Mean Square (LMS) algorithm, Sample Matrix Inversion (SMI) algorithm, Recursive Least Square (RLS) algorithm and their variants. The SMI algorithm has a faster convergence rate since it employs direct inversion of covariance matrix to compute the weights. This paper analyzes how weight vector and beam pattern of the smart antenna system are changing for different angles of arrival of desired signal and also for different number of antenna elements in an antenna array.
© 2016 IUP. All Rights Reserved.
Implementation of 2D Discrete Cosine Transform
Using Vedic Mathematic Algorithm
--R Mukherji, A K Saini, R K Chaurasia, V Mathur,
P Bhardwaj and M Mukherji
The paper presents the architecture and realization of a cost-effective FPGA realization of a Two-Dimensional Discrete Cosine Transform (2D DCT) for JPEG image compression. The architecture utilizes row-column decomposition of a fast 1D DCT algorithm implemented with distributed arithmetic. The work also used efficient multiplier architecture based on Urdhva-Tiryagbhyam sutra of ancient Indian Vedic mathematics. The paper explores the algorithmic evaluations, architectural design and development of Verilog models, verification methods, synthesis operations and timing analysis. This cost-effective design is optimized at different levels of abstraction, i.e., algorithm, architecture and gate levels. The design uses 1952 logic cells of one Vertex IV family FPGA and reaches an operating frequency of 85.12 MHz with the pipeline latency of 96 clock cycles.
© 2016 IUP. All Rights Reserved.
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