10 research outputs found
Design of Waveform Set for Multiuser Ultra-Wideband Communications
The thesis investigates the design of analogue waveform sets for multiuser and UWB communications using suitably
chosen Hermite-Rodriguez basis functions. The non-linear non-convex optimization problem with time and frequency
domains constraints has been transformed into suitable forms and then solved using a standard optimization package.
The proposed approach is more flexible and efficient than existing approaches in the literature. Numerical results show
that orthogonal waveform sets with high spectral efficiency can be produced
UWB Waveform Set Design using Löwdin’s Orthogonalization with Hermite Rodriguez Functions
In this paper we design a set of spectrally efficient orthogonal waveforms based on Hermite Rodriguez functions. The design is formulated as a semi-infinite quadratic programming problem and subsequently Löwdin method is used to generate a set of orthogonal waveforms. This approach is able to produce many overlapping orthogonal waveforms with high spectral efficiency
A Comparative Study between Traditional Learning and E-Learning
This paper presents a comparative study between Traditional and E-learning. Traditional learning involves a physical place where students and teacher can interact whereas E-learning is pursued in an e-space where a server and internet browsing interface is to be there. Due to a constant trend of growing student numbers across the world traditional learning will be expensive. The reason behind is the physical engagement of a teacher in this method which involves payment to the teacher for his service and other required support assets. E-learning can be a method which can ensure reduced cost while enhancing the outcome in the learning system. It is based on wireless communication networks which are widely and rapidly used due to the flexibility, freedom to use that it promotes an effective learning system. The wireless communication allows learner to receive the learning materials and lectures from anywhere as long as they are connected to the internet. Classroom education may not always succeed for online learning, when the instructor is not around which need to stimulate motivation and continual learning progress. In this paper we also discuss the merits and demerits of both the methods with the help of statistical data analysis
Design of spectrally efficient ultra-wideband waveforms using Hermite–Rodriguez functions
Spectral efficiency is a major requirement in ultra-wideband (UWB) communication systems because of very low power spectral density (PSD) regulations imposed on the transmitted signals. Besides, large number of orthogonal waveforms is highly desirable in multiuser systems. In this study, the design of a set of spectrally efficient orthogonal waveforms is investigated. The design of UWB waveforms based on orthogonal Hermite–Rodriguez basis functions and linear frequency modulation (LFM) is proposed herein. The design is formulated as a quadratic semi-infinite programming problem with spectral and orthogonality constraints. Numerical examples are presented to illustrate the effectiveness of Hermite–Rodriguez based waveforms with the proposed optimisation approach. Comparison with a recent result shows that the proposed approach compares favourably with those reported in the literatures in terms of the number of waveforms can be produced and the achievable spectral efficiency of the designed waveforms