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 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013
 Volume 1, Issue 1, Jan 2013

Volume 1, Issue 2, February 2013

International Journal of Advance Research in Electronics & Communication Engineering (IJOAREC)

Enhancement of Network Capacity of PON Using WDM and SONET/SDH[ ]

In recent era of digitalization life has become faster, but due to more and more digitalization we need to transmit and receive tremendous amount of data or in other words our bandwidth requirement is increasing like anything. In this era of competition and crisis we need efficient way to communicate which reduces overall budget. For the home applications like broadband and for the networks of big company’s best alternative is “fiber to home”. It refers to the installation and use of fiber optic cable directly to the home. Fiber Optic wiring replaces the duplicate infrastructure that the Telephone and Cable companies have installed in the past in a neighborhood setting. Fiber has a higher bandwidth capacity and can easily be used in traditional applications like telephone, television, and internet, for larger amount of data transmission with plenty of capacity left over for applications in the future. Active Fiber Optic Network is deployed using point to point active optics which requires power. So better option is Passive Optic Network (PON) which is deployed using passive optical splitter which doesn’t require any power hence they are “GREEN”.A passive optical network (PON) is a point-to-multipoint, fiber to the premises network architecture in which unpowered optical splitters are used to enable a single optical fiber to serve multiple premises[3]. There are many advantages to installing fiber to home. PON has advantages like Cost savings, Future proof Technology. PON works without electricity at end-user. PON is network without switches. The advantage of PON needs fewer ports in the exchange and thus less space and energy requirements for switches. In PON Downstream signals are broadcast to all premises sharing multiple fibers. Encryption can prevent eavesdropping. Upstream signals are combined using a multiple access protocol, usually time division multiple access (TDMA).Problem with PON is bandwidth for downstream. For upstream since it is using common fiber line and TDMA so uploading capacity of each user is limited. In this paper we described and showed how to enhance downstream capacity of PON using WDM and SONET and upstream capacity using higher level SONET. We can use WDM PON which uses a different wavelength for each user group to greatly enhance network capacity. E.g. we can divide each user group to OC-12 (622 Mbps). e.g. For downstream, Let initially we had 100 users, Now using WDM we can have 10 groups of 100 users operating at slightly diff. wavelengths on same fiber line. Now for 100 users we can allocate spaces in SONET rings for their we can have 1000 users using same fiber line. To increase upstream capacity we have used Higher SONET (e.g. OC-12) so for same time we can send more data from user to server using TDM.

Design and FPGA Implementation Of High Speed DA based DWT Processor for Image Compression[ ]

Discrete wavelet transform (DWT) is a widely used tool in image and video compression applications. Recently, the high-throughput DWT designs have been adopted to fit the requirements of real-time application. A scheme for the design of a high-speed FPGA architecture for the computation of the 2-D discrete wavelet transform (DWT) is proposed. In order to assess the feasibility and the efficiency of the proposed scheme, the architecture thus designed is simulated on a field-programmable gate-array . It is therefore a challenging problem to design an efficient VLSI architecture to implement the DWT computation for real-time applications. Owing to its regular and flexible structure, the design can be extended easily into different resolution levels, and its area is independent of the length of the 2-D input sequence. The implementation exploits the lookup table-based architecture of Virtex FPGAs, by reformulating the wavelet computation in accordance with the distributed arithmetic algorithm.Performance results show that the distributed arithmetic formulation results in a considerable performance gain compared with the conventional arithmetic formulation of the wavelet computation. Finally, we show that the FPGA implementation outperforms alternative software implementations of the discrete wavelet transform. Compared with other known architectures, our design requires the least computing time for DWT. Image Compression is one of the major Image Processing techniques that is widely used in medical, automotive, consumer and military applications. Discrete Wavelet Transformation technique adopted for Image Compression. Complexity of DWT is always high due to large number of arithmetic operations. In this work a high-speed DA based DWT architecture is proposed and is implemented on FPGA. This approach on virtex-II pro FPGA and operates at 825MHz.This architecture has a throughput of 125MHz.This design is 1.35 times faster than the reference design and it is suitable for application that require high speed image processing applications.Compared with other known architectures, our design requires the least computing time for DWT.

Performance Investigation Of YAGI-UDA Antenna Using Different Shapes Of Antenna Element at 2GHz[ ]

This paper is aimed to evaluate the performance of the Yagi-Uda Antenna with squared shaped Antenna element and compare its performance from conventional spherical shaped Yagi Antenna. For this job, two Yagi-Uda Antennas has been designed at 2GHz frequency with two different shape of Antenna element. The Antenna’s potential characteristics such as return loss, radiation pattern, have been measured for the analysis of proposed Antenna. The related designing parameters were also discussed in this paper.

Increased Spectral Efficiency and Reliable Performance of Time Frequency Training OFDM using MIMO Technique[ ]

In this paper, the high spectral efficiency of a transmission scheme called Time frequency training (TFT) Orthogonal frequency division multiplexing (OFDM) using MIMO system is proposed. The time frequency joint channel estimation for TFT-OFDM utilizes the time-domain training sequence without interference cancellation to merely acquire the time delay profile of the channel, while the path coefficients are estimated by using the frequency-domain group pilots. The redundant group pilots only occupy about 1% of the useful subcarriers, thus TFT-OFDM still has much higher spectral efficiency than Cyclic prefix OFDM (CP-OFDM) by about 10% and by extending it using Multiple Input Multiple Output (MIMO) which produce much higher spectral efficiency than TFT-OFDM. Simulation results also demonstrate that TFT-OFDM using MIMO gives better performance than CP-OFDM and TFT-OFDM over time-varying channels.

An Efficient comparison of MIMO OFDM Channel Estimation Algorithm[ ]

A multiple-input multiple-output (MIMO) wireless communication system combined with the orthogonal frequency division multiplexing (OFDM) modulation technique, which can achieve reliable high data rate transmission over broadband wireless channels. Channel state information for MIMO Channel systems based on pilot aided arrangement is included in this paper. The estimation of channel at pilot frequencies with conventional Least Square (LS) and Minimum Mean Square (MMSE) estimation algorithms is carried out through Matlab simulation. The performance of MIMO OFDM is evaluated on the basis of Bit Error Rate (BER) and Mean Square Error (MSE) level. Further enhancement of performance can be achieved through maximum diversity Space Time Block Coding (STBC) and Maximum Likelihood Detection at transmission and reception ends respectively. MMSE estimation has been shown to perform much better than LS for the MIMO system using pilot carriers.


This paper presents a multi-frequency Yagi-Uda array radiator. Electromagnetic interference plays a significant role in radiation characteristics of a Yagi-Uda Antenna system. For this paper, two array of dipoles are fabricated on a single supported common feed boom and achieve the electromagnetic interference along the axis and perpendicular to the axis of the controlling boom (which is discussed in detail below). The Antenna potential characteristics such as return loss, radiation pattern and beam-width are taken in account for the analysis of proposed Antenna.

Comparision Of Fractal Antenna And YAGI-UDA Antenna[ ]

A fractal antenna is an antenna that uses a fractal, self-similar design to maximize the length, or radiation within a given total surface area or volume. The Yagi consists of one driven element, plus one or more shorter elements acting as directors placed in front of it, plus one or more longer elements acting as reflectors placed behind it

Remote Sensing System Utilizing ZigBee Technology[ ]

wireless remote sensing system using the ZigBee standard is presented in this paper. This system is a wireless solution for monitoring purpose in cultural buildings in order to protect cultural heritage. The concept of this system utilizes ZigBee networks to carry and transmit data collected by sensors and store them into both local and remote databases. Thus, users can monitor the measured data locally or remotely. Especially, the power consumption is optimized to extend the lifetime of the battery-driven devices. Moreover, since the system has a modular architecture, it is easy to add extra services into this system.

Wireless Sensor Network[ ]

In Wireless Sensor Networks (WSN) having a high density of sensor nodes, spatially correlated measurements are transmitted, often redundantly, by many of the nodes whenever an event of interest is detected. In this work, we propose a correlation model to enable energy-efficient methodologies that exploit the spatial correlation at routing and MAC layers. At the routing layer, we first demonstrate how, through proper tuning, WSN is partitioned into disjoint correlated clusters without degrading the information reliability, thus enabling significant energy saving. On the other hand as an another contribution, at the MAC layer, we investigate the impact of correlation between nodes on achieved distortion in event estimation. We demonstrate that the same level of distortion constraint is achieved by selecting lesser nodes than those of existing correlation models. Furthermore, we show that even lesser number of representative nodes achieve the same event reliability when the selection criteria is based on a combination of correlation as well as received signal strength of the event source.


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