Reduced Complexity Optimal Hard Decision Fusion under Neyman-Pearson Criterion

Distributed detection is an important part of many of the applications like wireless sensor networks, cooperative spectrum sensing in the cognitive radio network. Traditionally optimal non-randomized hard decision fusion rule under Neyman Pearson(NP) criterion is exponential in complexity. But recently [4] this was solved using dynamic programming. As mentioned in [4] that decision fusion problem exhibits semi-monotonic property in a special case. We use this property in our simulations and eventually apply dynamic programming to solve the problem with further reduced complexity. Further, we study the e�ect of using multiple antennas at FC with reduced complexity rule

A Millimetre Wave Embroidered Antennas

WLAN and Body Area Networks(BAN) are rapidly advancing as high data rate wireless commu- nication systems using Ulta Wide Band(UWB) spectrum. The unlicensed UWB spectrum o�ers 7 GHz wide bandwidth which ranges over 57 to 64 GHz. In this UWB communication systems Antenna design plays a crucial role for signal transmission and reception. However Antenna de- sign at UWB spectrum is more challenging than narrow band design Beam forming Antenna arrays play an important role at these frequencies. In this work A novel embroidery type dipole antennas and dipole arrays are proposed for Body area networks. The proposed antennas are designed and analyzed using High Frequency Structure Simulator(HFSS)

Multilayer nanoparticle arrays for broad spectrum absorption enhancement in thin film solar cells

In this paper, we present a theoretical study on the absorption efficiency enhancement of a thin film amorphous Silicon (a-Si) photovoltaic cell over a broad spectrum of wavelengths using multiple nanoparticle arrays. The light absorption efficiency is enhanced in the lower wavelengths by a nanoparticle array on the surface and in the higher wavelengths by another nanoparticle array embedded in the active region. The efficiency at intermediate wavelengths is enhanced by the simultaneous resonance from both nanoparticle layers. We optimize this design by tuning the radius of particles in both arrays, the period of the array and the distance between the two arrays. The optimization results in a total quantum efficiency of 62.35% for a 300nm thick a-Si substrate.Comment: - Article Published in Optics Express on 7 Apr 2014. Link: http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-22-103-A80

Optimal quantised bits for estimation over a capacity and power limited, lossy channel

This letter considers the problem of estimating the state of a scalar dynamical system over a wireless channel that is lossy, capacity, and power limited. The limited power assumption, which is valid for most real problems, links the number of quantisation bits and packet error rate. As the number of quantisation bits increases, the quantisation noise decreases but the packet loss rate increases. It is shown that the estimation error variance (EEV) is minimised for a range of quantisation bits. Further, it is shown that operating beyond the optimal range sharply increases the EEV. Simulation results corroborating the analytical results are also presented

Improving the Detection Rate of Cosine Similarity detector in False Data Injection Attacks in Control Systems

Cyber Physical Systems are more vulnerable to attacks than the conventional systems because of the integrated nature of the cyber as well as physical environment.Replay attacks and False data injection attacks are in particular harmful because of their deceptive nature to traditional detectors. A popular traditional detector is Chi Square Detector which detects based on the statistics of devi- ations of the residual i.e. di�erence of observed measurement and estimated measurement. Since the statistics is not changed in the attacks mentioned above, Chi square detector fails to detect these. However, the Cosine detector proposed by [1] also fails in detecting these attacks in control system scenario. So in this work, we will show why the cosine detector fails to detect them and design a method to improve the detection rate of the Cosine Detector.

On Cooperative Spectrum Sensing with Improved Energy Detector over Erroneous Control Channel

In this paper, we present expressions for optimal number of secondary users (SUs) by minimizing the global error rate for a given fusion rule at the fusion center (FC). Expressions for optimal number of SUs are presented for AND, OR and MAJORITY fusion rules. We show that optimal number of SUs depends on effective probability of false alarm (P-fe) and effective probability of miss detection (P-me) of a SU over erroneous control channel. Using improved energy detector as an example feasibility regions are derived for OR, AND and MAJORITY rules

Computer Aided Multi-Parameter Extraction System to Aid Early Detection of Skin Cancer Melanoma

Melanoma is the most widely occurring and life threatening form of skin cancer. Early detection of in situ melanoma has challenged researchers for many decades now. Currently there exists no computer aided mechanisms to accurately detect early melanoma. T he currently existing computer aided diagnostics mechanisms are capable of melanoma classification and are unable to detect in situ melanoma. This paper introduces a Multi Parameter Extraction and Classification System ( 푀푀푀푀푀 ) to aid early detection o f skin cancer melanoma. The 푀푀푀푀푀 defines the skin lesion images in terms of characteristic parameters which are further used for classification. In this paper the extraction of 21 parameters is achieved using a six phase approach. The parameters extr acted are analyzed using statistical methods. It is clear from the results obtained that no single parameter can affirm the detection of in situ melanoma, hence an advanced analysis mechanisms considering all the parameters need to be adopted to effective ly detect melanoma in its initial stages