A Privacy-Preserving Asynchronous Averaging Algorithm based on State Decomposition

Average consensus algorithms are used in many distributed systems such as distributed optimization, sensor fusion and the control of dynamic systems. Consensus algorithms converge through an explicit exchange of state variables. In some cases, however, the state variables are confidential. In this paper, a privacy-preserving asynchronous...

Clock-Offset and Microphone Gain Mismatch Invariant Beamforming

The use of wireless acoustic sensor networks (WASNs) has received increased attention over the last decade. The advantages of WASNs over stand-alone multi-microphone devices are that the microphone array is not anymore limited by the dimensions of a single device, and that microphones can be placed at arbitrary locations. One of the...

Sensor selection and rate distribution based beamforming in wireless acoustic sensor networks

Power usage is an important aspect of wireless acoustic sensor networks (WASNs) and reducing the amount of information that is to be transmitted is one effective way to save it. In previous contributions, we presented sensor selection as well as rate distribution methods to reduce the power usage of beamforming algorithms in WASNs. Taking...

A method for determining the position of FBG sensors accurately

Fibre Bragg grating sensors have gained a lot of attention in damage detection and strain measurement applications in the past few decades. These applications include matrix crack detection and delamination tip monitoring in composite structures, crack detection in concrete and civil engineering structures and etc. The damage localisation...

Analysis of FBG reflection spectra under anti-symmetrical strain distributions using the approximated transfer matrix model

In this paper, we used the efficient formulation of the approximated transfer matrix model (ATMM) for the analysis of fibre Bragg grating (FBG) sensors' response under anti-symmetrical strain fields. Exploiting the flexible representation of the transfer matrices in this new model, we will analytically prove that any sort of anti-symmetrical...

Analysis of the Side-Lobes of FBG Reflection Spectra from Matrix Cracks in Composites

The previously described approximated transfer matrix model (ATMM) provides insight into the strain distribution along on fibre Bragg grating (FBG) sensor. In this paper we study the influence of matrix cracks in composites on the angular frequency of the side-lobes of the FBG reflection spectra in frequency space.

Classification of composite damage from FBG load monitoring signals

This paper describes a new method for the classification and identification of two major types of defects in composites, namely delamination and matrix cracks, by classification of the spectral features of fibre Bragg grating (FBG) signals. In aeronautical applications of composites, after a damage is detected, it is very useful to know the...

Modelling non-uniform strain distributions in aerospace composites using fibre Bragg gratings

In this paper the behaviour of fibre Bragg grating (FBG) sensors under non-uniform strain distributions was analysed. Using the fundamental matrix approach, the length of the FBG sensor was discretised, with each segment undergoing different strain values. FBG sensors that are embedded inside composites, also undergo such non-uniform strain...

Structured Total Least Squares Based Internal Delay Estimation For Distributed Microphone Auto-Localization

Auto-localization in wireless acoustic sensor networks (WASNs) can be achieved by time-of-arrival (TOA) measurements between sensors and sources. Most existing approaches are centralized, and they require a fusion center to communicate with other nodes. In practice, WASN topologies are time-varying with nodes joining or leaving the network,...

Improved multi-microphone noise reduction preserving binaural cues

We propose a new multi-microphone noise reduction technique for binaural cue preservation of the desired source and the interferers. This method is based on the linearly constrained minimum variance (LCMV) framework, where the constraints are used for the binaural cue preservation of the desired source and of multiple interferers. In this...

Greedy Gossip Algorithm with Synchronous Communication for Wireless Sensor Networks

Randomized gossip (RG) based distributed averaging has been popular for wireless sensor networks (WSNs) in multiple areas. With RG, randomly two adjacent nodes are selected to communicate and exchange information iteratively until consensus is reached. One way to improve the convergence speed of RG is to use greedy gossip with eavesdropping (GGE...

On the Impact of Quantization on Binaural MVDR Beamforming

Multi-microphone noise reduction algorithms in binaural hearing aids which cooperate through a wireless link have the potential to become of great importance in future hearing aid systems. However, limited transmission capacity of such devices necessitates the data compression of signals transmitted from one hearing aid to the contralateral one....