Chittagong University of Engineering & Technology

About: Chittagong University of Engineering & Technology is a education organization based out in Chittagong, Bangladesh. It is known for research contribution in the topics: Renewable energy & Dielectric. The organization has 1200 authors who have published 1444 publications receiving 10418 citations. The organization is also known as: Engineering College, Chittagong & Bangladesh Institute of Technology, Chittagong.

Soft decision multi-stage threshold decoding with sum-product algorithm

Abstract: Sum-Product Algorithm (SPA) is usually used in LDPC codes. This paper presents a method to improve the performance of soft decision multi-stage threshold decoding (SMTD) by using SPA. Parity check coding is used to improve further. This paper also presents a brief comparison among various multi-stage threshold decoding (MTD) techniques. SPA concatenated (ConC) with SMTD and parity check code is also compared with specific types of repeat accumulate (RA) code and LDPC code. The SPA ConC with SMTD outperforms the conventional multi-stage threshold decoding techniques having a performance gain of 0.3 dB to 0.7 dB at bit error rate (BER) of 10−5. Furthermore, the SPA ConC with SMTD and parity check code gives 0.2 dB performance gain over the SPA ConC with only SMTD at BER of 10−5.

An Approach Towards Intelligent Accident Detection, Location Tracking and Notification System

Abstract: Advancement in transportation system has boosted speed of our lives. Meantime, road traffic accident is a major global health issue resulting huge loss of lives, properties and valuable time. It is considered as one of the reasons of highest rate of death nowadays. Accident creates catastrophic situation for victims, especially accident occurs in highways imposes great adverse impact on large numbers of victims. In this paper, we develop an intelligent accident detection, location tracking and notification system that detects an accident immediately when it takes place. Global Positioning System (GPS) device finds the exact location of accident. Global System for Mobile (GSM) module sends a notification message including the link of location in the google map to the nearest police control room and hospital so that they can visit the link, find out the shortest route of the accident spot and take initiatives to speed up the rescue process.

Distributed Energy Resources Optimization for Wireless Base Stations using Power Amplifier Switching

Abstract: With the increased deployment of cellular networks due to advanced transmission techniques, overall energy consumption of the telecommunication sector across the globe has grown. Numerous challenges for operators are springing up including the escalating number of base station (BS) sites and also the increasing operation cost as well as environmental impacts due to the use of sources such as fossil fuel. Therefore, to achieve optimization in power consumption of cellular network, global network operators are deploying different energy-saving strategies. In this paper, a simple software-based effective power amplifier switching algorithm requiring no change of infrastructure is proposed to save a significant amount of energy at the base station using a real-time traffic scenario. The proposed algorithm uses the Transmit Channel Allocation method to switch the power amplifier ON/OFF at the transceivers of BS sites automatically based on the continuous traffic analysis. To validate the proposed algorithm, a model consisting of 5 BSs with a solar system is considered, and the power amplifier switching algorithm is run via Matlab at these BSs to record the hourly power consumption over the year. The resulting optimized BSs power load represents a 17.31% reduction in average power consumption over the course of one year. A battery storage model using real-world hourly irradiance and temperature for 5 BSs was used to analyze the grid dependency of the model for both optimized and unoptimized annual load. Grid power utilization for both cases is compared to conclude that the proposed algorithm improved the overall power efficiency and lowered the cost of operation of the cellular network by reducing the average power consumption of the BSs. The hybrid solar power BS model using an optimum battery storage capacity became more grid independent with a 72.14% reduction in grid dependency as an impact of the optimization achieved using the proposed PA switching algorithm.

Converter based Frequency Adjustment and Protection of Grid-tied Wind Farm

Abstract: Frequency adjustment and protection of a wind turbine due to wind gust is a salient aspect of the grid-tied wind farm. Both of them require conserving system stability. This paper presents an investigation of the converter based frequency adjusting method and wind turbine protection. A grid-tied wind power system model using the Doubly Fed Induction Generator in MATLAB is used. To regulate the active power output, synchronization between wind velocity and wind turbine speed is adjusted. Thus, wind farm operated at grid frequency and maximize turbine output. The control strategy of the converter based frequency synchronization of a grid-tied wind farm also includes protection subsystem. The protection system executed by receiving information from the logical block implemented in the wind farm model. It provides wind turbine protection by terminating wind turbine from a grid in abnormal wind conditions. The Simulation result validates the results and control methods.

Low power CMOS IR-UWB transmitter for bio-sensing meeting FCC restrictions

Abstract: This paper presents an FCC (Federal Communications Commission) compliant impulse radio (IR) ultra-wideband (UWB) low power CMOS indoor Gaussian pulse transmitter for bio-sensing specially targeted for vital sign monitoring system. For non-invasive and continuous monitoring, meeting low power is crucial and it is challenging and highly desirable to tune the operating frequency of an IR-UWB transmitter working as a biosensor. In this paper, the transmitter is designed for the most desirable feature of IR-UWB that is low power and spectral tuning which is solved using underdamped operation of RLC circuit incorporated with three step amplitude tuning. Simulation results of the presented design are carried out in Advanced Design System 2009 where exact spectrum generation with center frequency 5, 7 and 9GHz is tested and found the lowest energy consumption 3.51pJ/pulse.