SDRs

In this paper area efficient and cost effective techniques for design of pulse shaping filter have been
presented to improve the computational and implementation complexity. Pulse shaping filters have been
designed and implemented by using Raised cosine filter, Nyquist filter and optimized half band filters for
software defined radio (SDR) based wireless applications. The performance of different filters is compared
in terms of BER and hardware requirements. The results show that the BER performance of the optimized
designs is almost identical to the Raised cosine filter with significant reduction in hardware requirements.
The hardware saving of 60% to 90% can be achieved by replacing the Raised cosine filter with proposed
filters to provide cost effective solution for wireless communication applications.

Software defined radio (SDR) technology enables implementation of wireless devices that support multiple air-interfaces and modulation formats, which is very important if consider proliferation of wireless standards. To enable such functionality SDR is using reconfigurable hardware platform such as Field Programmable Gate Array (FPGA). In this paper, we present design procedure and implementation result of SDR based QPSK modulator on Altera Cyclone IV FPGA. For design and implementation of QPSK modulator we used Altera DSP Builder Tool combined with Matlab/Simulink, Modelsim and Quartus II design tools. As reconfigurable hardware platform we used Altera DE2-115 development and education board with AD/DA daughter card. Software and Hardware-in-the-loop (HIL) simulation was conducted before hardware implementation and verification of designed system. This method of design makes implementation of SDR based modulators simpler ad faster.

Emergent aquatic weeds present in the monocropped fresh water wetland area of Bangladesh create a hazard in land preparation by developing dense stands. A field experiment was conducted at the farmers’ field of two villages namely Mahilara and Kashemabad under Gournadi Upazila of Barisal district, Bangladesh during October 2012 to evaluate the efficacy of Gramoxone 20SL (Paraquat) in controlling emergent aquatic weeds and to find out an appropriate dose of this herbicide. Three doses of Gramoxone 20SL at 1.96 l·ha-1, 2.00 l·ha-1 and 2.04 l·ha-1 were tried with an untreated control. All treatments were laid out in a randomized complete block design and replicated thrice. There were 8 different emergent weed species infesting the field among which the most dominant weed species were Eichhornia crassipes, Pistia stratiotes, Enhydra fluctuans, Monochoria vaginalis, Echinochloa crus-galli. The results revealed that, weed control efficiency was significantly affected by different herbicidal treatments. The treatments, Gramoxone 20SL at 2.00 l·ha-1 and 2.04 l·ha-1 were controlled in all the emergent aquatic weeds more than 85% infesting both the sites. Application of non-selective herbicide Gramoxone 20SL at 2.00 l·ha-1 prior to land preparation was most effective to suppress weed dry masses in both the site resulting reduced land preparation cost up to 78.93% as compared to manual weed control.

Designing proper spectrum decision schemes for cognitive radios (CRs) improves spectral usage efficiency as well as CR network throughput. One of the key effecting factors of the CR network throughput is the spectrum sensing sequences of the secondary users (SUs). In this paper, the SUs throughput maximization through appropriately selecting the sensing sequences of the SUs, called sensing matrix (SM), is investigated. More specifically, first the average throughput of the CR network is evaluated for a given SM in the case of error-free channel sensing. Then, an optimization problem is formulated with the aim to maximize the network throughput by finding the optimal SM. In order to avoid major challenges associated with the optimal solution, a novel sub optimal solution is proposed. Despite of having less computational complexity as well as lower consumed energy, the proposed solution performs quite well compared to the optimal solution (the optimal SM). Required considerations for the extension of the proposed approach to the case of non-perfect sensing are discussed, and then a set of illustrative numerical results is presented to validate its efficiencies.

This paper investigates the effect of
large Frequency Offset Induced (FOI) Intersymbol
Interference (ISI) on the performance of a digital
receiver and proposes corresponding remedies.
General expressions are derived for the exact
representation of ISI caused by an arbitrary
frequency offset at the output of the receiver
matched filter. Specific examples are developed for
the case of a Square Root Raised Cosine (SQRTRC)
pulse shape. It is shown that when FOI ISI
compensation is performed digitally after the
matched filtering operation, an equalizer is
necessary for efficient data demodulation, even in
the case of a non - dispersive channel. Maximum
Likelihood (ML) frequency offset estimation is
revisited to accommodate the case of large FOI ISI.
Its performance is assessed via simulation examples
and compared to the derived Cramer-Rao bound. A
combined equalization – frequency tracking scheme
is also explored, in order to cope with residual
frequency estimation errors and potential phase
noise.

The investigation of neuron structures is an incredibly difficult and complex task that yields relatively low rewards in terms of
information from biological forms (either animals or tissue). The structures and connectivity of even the simplest invertebrates
are almost impossible to establish with standard laboratory techniques, and even when this is possible it is generally time
consuming, complex and expensive. Recent work has shown how a simplified behavioural approach to modelling neurons can allow
“virtual” experiments to be carried out that map the behaviour of a simulated structure onto a hypothetical biological one, with
correlation of behaviour rather than underlying connectivity. The problems with such approaches are numerous. The first is the
difficulty of simulating realistic aggregates efficiently, the second is making sense of the results and finally, it would be helpful to have
an implementation that could be synthesised to hardware for acceleration. In this paper we present a VHDL implementation of Neuron models that allow large aggregates to be
simulated. The models are demonstrated using a system level VHDL and VHDL-AMS model of the C. Elegans locomotory system.

The interest in cloud computing by organizations has driven a core desire to
become more effective and efficient with information technology (IT). Cloud
computing enables organizations to utilize instantly provisioned scalable IT
resources on a pay-per-use basis. The wireless grid provides a new model for heterogeneous devices to share physical and virtual resources within an adhoc environment with no dedicated server needed to manage the network.
Both of these technologies provide new opportunities to provide innovative
architectures but also have a number of security related issues that concern
many potential users. Despite the potential benefits, each integration of a
cloud computing and a wireless grid architecture raise even more concerns
related to information security than each architecture alone. As a new
paradigm for organizational strategic initiatives, these are the issues which
prevent cloud computing and wireless grid solutions from becoming the
prevalent integration for an operational system. This article will identify a
wireless cloud architecture and identify potential vulnerabilities and threats
to a wireless cloud solution. We also identify the beginnings of a promising
wireless grid security architecture, which focuses on a wireless cloud
authentication, authorization and access control process.

Copyright @ 2012 Institute of Advanced Engineering and Science.
All rights reserved.

In this paper we are proposing a new concept in MAC layer protocol design for Cognitive radio by combining information held by physical layer and MAC layer with analytical engine based on knowledge based reasoning approach. In the proposed system a cross layer information regarding signal to
interference and noise ratio (SINR) and received power are analyzed with help of knowledge based reasoning system to determine minimum power to transmit and size of contention window, to minimize backoff, collision, save power and drop packets. The performance analysis of the proposed protocol
indicates improvement in power saving, lowering backoff and significant decrease in number of drop packets. The simulation environment was implement using OMNET++ discrete simulation tool with Mobilty framework and MiXiM simulation library.

The paper presents new approach to designing high efficient adaptive transmitting units (TU) for the sensor nodes of wireless sensor nets (WSN). Particularity of the considered TU is lack of digitizing and coding units. The signals formed by the sensors are transmitted to the base station (BS) using pulse-amplitude modulator adaptively adjusted during the samples transmission. The BS computes estimates of the origin signal, as well as the adjusting controls transmitted to TU through the feedback channel. Transition to the analogue transmission in the channel “node-BS” simplifies the construction of TU and enables development of analytical methods permitting to design optimal TU capable to transmit the signals to BS with minimal MSE and bit-rate equal to the capacity of the channel. The signals emitted by optimal TU have the form of realizations of white Gaussian noise that increases information security of data-transmission. The results of research enable transition to the practical design of low energy and low cost optimal TU which ensure “ideal” power-bandwidth trade off, i.e. work at the Shannon boundary.

Security in every aspect is highly desirable may be at home or at office. Automated system specially designed to safeguard personal belonging, country’s secret, protection of secret research data, simple university building or a personal car, have been designed using various techniques of computing world both, software and hardware.
This paper tries to implement hardware based approach of designing security system. In this project FPGA based security system is designed capable of unlocking the door once the correct code is entered from DE2 board. Finally the output of overall system is evaluated based on the display on LCD present on De2 board of Altera Company.

VHDL models for neural networks for automatic test generation of gate level circuits are presented in this paper. A program converts a gate netlist to its equivalent neural model. A good circuit and faulty bad circuits will be generated. A VHDL test bench has been developed to apply the faults to the neural network bad circuit model, and report tests that are generated for each injected fault.

Este art'iculo presenta un enfoque general para manejar los eventos de duraci'on breve en la sem'antica de los lenguajes de programaci'on de tiempo real, usando como ejemplo el lenguaje de descripci'on hardware VHDL, est'andar del IEEE.  Introducimos infinitesimales en la l'inea del tiempo para modelar dichos eventos. Demostramos que esto no afecta a la sem'antica que modela el comportamiento en tiempo apreciable.

In the past decade, with an increased focus on core competencies, support functions and basic engineering designs have been increasingly outsourced. To this day, however, success is illusive to many outsourcers. This paper focuses on the potential of the Outsourcing and more on the capability of Bangladesh and how it can contribute to the International Engineering Outsourcing Arena. This research paper is done remembering the $55 billion outsourcing market of India, our neighboring country. We find that communication, the engagement of the appropriate resources, a mutual understanding of service delivery objective, and a cooperative, trust-building relationship can improve the chance of completing outsourcing initiatives successfully. The primary focus of the outsourcing Engineering Teams will be to support the engineering, design, and manufacturing and test needs of the manufacturing customers. Bangladesh can emerge as a very strong option In the International Engineering Outsourcing arena if proper steps are taken from now on. We put these findings into an outsourcing management framework for designs of PCB, FPGA, ASIC and even integration and synthesis of medium and small chips at a very low cost.