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.

Estimation of link range and bit rate for 16 channel WDM-FSO considering atmospheric turbulence and pointing error under various weather conditions

Abstract: To meet the increasing demand of bandwidth and speed, Free Space Optics (FSO) has been emerged as a promising wireless communication technique leading behind the conventional copper wire and fiber optic communications. The capacity of this cost-effective and rapidly deployable FSO system can be increased using Wavelength Division Multiplexing (WDM) technique. Atmospheric turbulence and pointing error are two constant phenomena in FSO that affect transmitted signal strength along with different critical weather like haze, rain, snow and fog. This paper presents a complete overview of WDM-FSO system in terms of link range and bit rate considering all the impediments of Free-Space channel i.e. how long the signal can propagate and how much bit rate the WDM-FSO system can support maintaining the acceptable value of Bit Error Rate (BER) of 10−9 and Quality factor of 6 in an atmospheric turbulent channel with pointing error under various weather conditions like haze, moderate rain and foggy weather. It is found that using 5 × 10−15 m−2/3 as the value of the index of refraction structure for atmospheric turbulence and respective maximum allowable pointing error, the maximum attainable link range is 5.4km, 3.1km and 1.1km for haze, moderate rain and fog respectively at a constant bit rate of 2.5Gbps and the maximum attainable bit rate is 9Gbps, 6.5Gbps and 2.5Gbps for haze, moderate rain and foggy weather respectively at a constant link range of 2.2km for haze and moderate rain and 1.1km for fog.

Installation of a Solid-Waste fuelled Power Plant in Chittagong, Bangladesh: A feasibility study

Abstract: Global interest in renewable energy resources from organic solid wastes has increased, as there is a huge amount of energy locked in these wastes. A study on the potential of such energy resources is presented in the paper. It is estimated that a Solid-Waste fuelled Power Plant (SWFPP) of 8-MW is feasible to be installed in Chittagong City Corporation (CCC), Bangladesh. The technology and cost analysis of such a power plant is also presented in the paper.

Single Feed Circularly Polarized Crescent-Cut and Extended Corner Square Microstrip Antennas for Wireless Biotelemetry

Abstract: In this paper, the development of two novel circularly polarized microstrip antennas is thoroughly explained. These antennas are fed by coaxial feeding technique. One of the primary objectives of the proposed work is to tune the antennas to work in ISM band. This frequency band refers to the internationally recognized radio frequency bandwidth which is to be used explicitly for Industrial, Scientific, and Medical applications. Therefore, these antennas would be suitable to use in the field of wireless biotelemetry. Two new antenna design techniques have been introduced to produce circular polarization, and details of these schemes are described. The proposed microstrip antennas are designed and simulated on Advanced Design System (ADS) software. The return loss of the proposed crescent-cut antenna is -19.3 dB at the operating frequency. The extended corner antenna has the return loss of -29.3 dB at the tuned frequency. The simulation results are also presented and discussed.

Modeling and simulation of highly efficient ultra-thin CIGS solar cell with MoSe2 tunnel

Abstract: The main objective of this research work is to improve the efficiency of CIGS solar cells in ultra-thin approach. A detail numerical analysis on the insertion of a thin MoSe2 tunnel layer between the ultra thin CIGS absorber and the back contact in ultra-thin CIGS solar cell is investigated by using a solar cell simulator wxAMPS. The MoSe 2 layer between CIGS absorber and Mo back contact provides an additional hole tunneling action that forms a quasi ohmic contact near the back surface region and BSF action also. The quasi ohmic contact improves the efficiency of carrier collection and BSF action reduces the back surface recombination. From the above-mentioned discussions, it can be clearly showed that the efficiency obtained by the conventional CIGS cells is lower if compared to the values reached by the proposed ultra-thin CIGS solar cells with an additional MoSe 2 layer (at the level of 25%). Conversion efficiency of 21.20 % has been achieved for the conventional ultra thin CIGS structure (1μm CIGS lower) and improved conversion efficiency of 25.46 % has been gained for the proposed ultra-thin cell with an additional thin layer of MoSe 2 . Thermal stability of the proposed ultra thin CIGS solar cell has also been investigated.