This community is made up of electronic copies of books, chapters and sections produced by staff and students of Botswana International University of Science and Technology. https://repository.biust.ac.bw/handle/123456789/136 2026-04-14T22:49:18Z 2026-04-14T22:49:18Z Bandele, Jeremiah Oluwatosin Salau, Ayodeji Olalekan Mangwala, Mmoloki Zungeru, Adamu Murtala https://repository.biust.ac.bw/handle/123456789/584 2024-06-14T07:53:34Z 2023-10-06T00:00:00Z

Multiple transmitters for gain saturated pre-amplified FSO Communication Systems limited by strong atmospheric turbulence and pointing error Bandele, Jeremiah Oluwatosin; Salau, Ayodeji Olalekan; Mangwala, Mmoloki; Zungeru, Adamu Murtala The use of multiple transmitters in a turbulent free-space optical (FSO) communication link can enhance the systems performance because greater received power can improve receiver sensitivity. Nevertheless, the effect of having more power at the receiver can be severe. This paper investigates the impact of using multiple transmitters in preamplified FSO communication links limited by strong atmospheric turbulence (AT), amplified spontaneous emission noise, fixed path loss and pointing errors (PEs) using different preamplifier operating modes and different decision thresholding schemes. Results obtained show that regardless of the number of transmitters used, the best bit error rate (BER) performances are obtained with normalised decision threshold levels of about 0.2 and 0.5 when the decision thresholding scheme at the receiver is non-adaptive and adaptive, respectively. Also, in the strong AT regime, an additional transmitted power of about 7dB is required for the FSO communication systems under minimal PE effects to have the same performance as FSO communication systems without PE. The results also show that when the effects of PE are absent or minimal, a larger receiver would require about 15dB less transmitted power to record the same performance as a smaller receiver. However, with a non-adaptive decision threshold, smaller receivers perform better than larger receivers when the PE effects are severe. Additionally, it is shown in this paper that when the effects of PE is severe, the BER performances consistently get better with more transmitters regardless of the decision thresholding scheme employed at the receiver. However, in the absence of PEs, increasing the number of transmitters indefinitely will not always guarantee improved BER performances when the receiver decision threshold is non-adaptive. The use of multiple transmitters is particularly advantageous for applications where it is either necessary or unavoidable to use lower transmitted power.

2023-10-06T00:00:00Z Jamisola, Rodrigo S. https://repository.biust.ac.bw/handle/123456789/414 2022-04-01T07:28:33Z 2021-09-09T00:00:00Z

Laboratory manual, Artificial intelligence and machine learning for engineers Jamisola, Rodrigo S. This book is a collection of all laboratory exercises for the course Artificial Intelligence and Machine Learning for Engineers, a fifth-year level course for the program Bachelor of Engineer in Mechatronics and Industrial Instrumentation in Botswana International University of Science and Technology, Palapye, Botswana. The exercises were designed to enhance the understanding of the students to complement the topics discussed in the lectures. Most of the exercises require the students to perform manual computations in order to enhance their theoretical understanding. This book includes the course syllabus as well as lecture slides for the entire semester. Interested students can attend virtual class discussions uploaded on YouTube via the channel of the author. Laboratory Maunal

2021-09-09T00:00:00Z Tafo, Joël Bruno Gonpe Nana, Laurent Tabi, Conrad Bertrand Kofané, Timoléon Crépin https://repository.biust.ac.bw/handle/123456789/320 2021-08-16T11:17:07Z 2020-03-11T00:00:00Z

Nonlinear dynamical regimes and control of turbulence through the complex Ginzburg-Landau equation Tafo, Joël Bruno Gonpe; Nana, Laurent; Tabi, Conrad Bertrand; Kofané, Timoléon Crépin The dynamical behavior of pulse and traveling hole in a one-dimensional system depending on the boundary conditions, obeying the complex Ginzburg-Landau (CGL) equation, is studied numerically using parameters near a subcritical bifurca- tion. In a spatially extended system, the criterion of Benjamin-Feir-Newell (BFN) instability near the weakly inverted bifurcation is established, and many types of regimes such as laminar regime, spatiotemporal regime, defect turbulence regimes, and so on are observed. In finite system by using the homogeneous boundary conditions, two types of regimes are detected mainly the convective and the absolute instability. The convectively unstable regime appears below the threshold of the parameter control, and beyond, the absolute regime is observed. Controlling such regimes remains a great challenge; many methods such as the nonlinear diffusion parameter control are used. The unstable traveling hole in the one- dimensional cubic-quintic CGL equation may be effectively stabilized in the chaotic regime. In order to stabilize defect turbulence regimes, we use the global time-delay auto-synchronization control; we also use another method of control which consists in modifying the nonlinear diffusion term. Finally, we control the unstable regimes by adding the nonlinear gradient term to the system. We then notice that the chaotic system becomes stable under strong nonlinearity.

2020-03-11T00:00:00Z