Entropy-Based Local Irregularity Detection for High-Speed Railway Catenaries With Frequent Inspections

The condition-based maintenance of high-speed railway catenary is an important task to ensure the continuous availability of train power supply. To improve the condition monitoring of catenary, this paper presents a novel scheme to detect catenary local irregularities using pantograph head acceleration measurements. First, a series of...

Barely visible impact damage assessment in laminated composites using acoustic emission

Despite the key advantages of Fiber Reinforced Polymer (FRP) composites, they are susceptible to Barely Visible Impact Damage (BVID) under transverse loadings. This study investigates BVID in two quasi-isotropic carbon/epoxy laminates under quasi-static indentation and Low-Velocity Impact (LVI) loadings using Acoustic Emission (AE). First,...

Ripples in Communication: Reconfigurable and Adaptive Wireless Communication Systems based on Wavelet Packet Modulators

Wavelet Packet Modulation (WPM) is a multi-carrier transmission technique that uses orthogonal wavelet packet bases to combine a collection of information bits into a single composite signal. This system can be considered as a viable alternative, for wide-band communication, to the popular Orthogonal Frequency DivisionMultiplexing (OFDM) system....

A Study On Wavelet Packet Based Algorithm For Representation of Wireless Channel

Wireless telecommunication services are growing rapidly both in terms of the underlying technology as well as in the nature of the applications. The trends point to further growth in the foreseeable future. However, the dynamic nature of the wireless channel places fundamental limitations on the performance of wireless communication system....

Synchronization Methods for Wavelet Packet Multicarrier Modulation

Wavelet Packet based Multi-Carrier Modulation (WPM) offers an alternative to the well-established Orthogonal Frequency Division Multiplexing (OFDM) as an efficient multicarrier modulation technique. It has strong advantage of being generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements...

Channel Equalization for Wavelet Packet Modulation

This thesis work presents design and implementation of a channel equalizer for wavelet packet modulation.

An investigation on the sensitivity of wavelet packet modulation to time synchronization error

Wavelet Packet based Multi-Carrier Modulation (WPMCM) offers an alternative to the well-established OFDM as an efficient multicarrier modulation technique. It has the advantage of being a generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements and constraints of advanced communication...

On Wavelet Based Spectrum Estimation for Dynamic Spectrum Access

One of the important functionalities of Dynamic Spectrum Access is spectrum estimation. Accuracy and speed of estimation are the key indicators to select the appropriate spectrum estimation technique. In this thesis work, the possibility of employing wavelet packet decomposition as a basis for a new spectrum estimation approach is investigated....

Performance Evaluation of WPMCM with Carrier Frequency Offset and Phase Noise

Wavelet Packet based Multi-Carrier Modulation (WPMCM) offers an alternative to the well-established OFDM as an efficient multicarrier modulation technique. It has strong advantage of being a generic transmission scheme whose actual characteristics can be widely customized to fulfill several requirements and constraints of an advanced...

Construction of Optimum Wavelet Packets for Multi-Carrier Based Spectrum Pooling Systems

The growing popularity of wireless applications has placed enormous burden on valuable resources such as spectral bandwidth. This has brought about a major revamp of traditional resource allocation policies culminating in an explosion of research activity in the field of cognitive radio (CR) (Mitola, Cognitive radio: an integrated agent...