UNDERGROUND WIRELESS COMMUNICATION CHANNEL MODELING AND SIMULATION USING 0.3GMSK MODULATION CONSIDERING PENETRATION AND SCATTERING LOSS

Wireless communication inside mines and tunnels is very different from that in terrestrial environment because of the strong attenuation of signals. Here, we are developing an empirical model for the underground wireless communication channel based on experimental data which help in predicting the average received signal strength at a given distance from transmitter. The model aims at adding correction factors to the available outdoor and indoor propagation models such as Okumara-hata model, cost231 model, ITU indoor propagation models etc. Modeling is done by choosing the most appropriate model among the available ones and performing regression methods to the model based on experimental data. Correction factors are then added based on two parameters which we are considering namely- Penetration and Scattering loss for 0.3GMSK

A Secure Image Steganography using LSB, DCT and Compression Techniques on Raw Images

Steganography is an important area of research in recent years involving a number of applications. It is the science of embedding information into the cover image viz., text, video, and image (payload) without causing statistically significant modification to the cover image. The modern secure image steganography presents a challenging task of transferring the embedded information to the destination without being detected. In this paper we present an image based steganography that combines Least Significant Bit(LSB), Discrete Cosine Transform(DCT), and compression techniques on raw images to enhance the security of the payload. Initially, the LSB algorithm is used to embed the payload bits into the cover image to derive the stego-image. The stego-image is transformed from spatial domain to the frequency domain using DCT. Finally quantization and runlength coding algorithms are used for compressing the stego-image to enhance its security. It is observed that secure images with low MSE and BER are transferred without using any password, in comparison with earlier works

Generation of ultrashort electrical pulses in semiconductor waveguides

We report a novel device capable of generating ultrashort electrical pulses on a coplanar waveguide (CPW) by means of optical rectification. The device consists of a completely passive GaAs-based optical waveguide, which is velocity matched to a CPW line. Optical pulses are injected into the device and electrical pulses are collected at the output. Experimental results obtained in the laboratory show the potential of this device for high speed optical-to-electrical conversion

A Progressive Approach to Enhance Lifetime for Barrier Coverage in Wireless Sensor Network

Wireless sensor networks have their applications deployed in all the fields of area of research beyond the visualization of smart sensors. The sensors installed may experience many coverage related faults e.g., Barrier coverage problem. This problem affects the random deployment in sensor network to conserve energy and therefore has to be rectified, confined and approved. The protocol CSP andVSP defined extends the advantageoreducingtheenergyconsumption and increases the lifetime of sensor nodes with the intrusion detection model over heterogeneous deployment. Inspite of low connectivity and multihop signal paths, the protocols is entirely scalabl e in terms of computational control and communication bandwidth. Two diverse cases are employed between th e nodes with the protocols: position to position connectivity and load balancing. The former produces better results with a linear increase in network lifetime whereas through latter achieves 40 percent of energy utilization. Simul ation results are provide d to display the efficiency of the protocol designed

Multi-hop optimal position based opportunistic routing for wireless sensor networks

Wireless sensor network is a collection of a group of sensors connected to monitor an area of interest. Installation flexibility, mobility, reduced cost and scalability have given popularity to wireless sensor networks. Opportunistic routing is a routing protocol that takes the advantage of broadcasting nature of wireless sensor network for multi-hop communication. Considering the importance of communication between source-destination pairs in a wireless sensor network a Multi-hop Optimal position based Opportunistic Routing (MOOR) protocol is proposed in this paper. The algorithm chooses the path with minimum distance and number of hops between source and destination for transmission of data in the network. It is illustrated by simulation experiments that the proposed protocol has a good effect on End-to-End delay and lifetime of the network. In addition, it is observed that the average End-to-End delay is lesser for different simulation times when compared with existing EEOR protocol

Intra-modal Score level Fusion for Off-line Signature Verification

Signature is widely used as a means of personal verification which emphasizes the need for a signature verification system. Often the single signature feature may produce unacceptable error rates. In this paper, Intra-modal Score level Fusion for Off-line Signature Verification (ISFOSV) is proposed. The scanned signature image is skeletonized and exact signature area is obtained by preprocessing. In the first stage 60 centers of signature are extracted by horizontal and vertical splitting. In the second stage the 168 features are extracted in two phases. The phase one consists of dividing the signature into 128 blocks using the center of signature by counting the number of black pixels and the angular feature in each block is determined to generate 128 angular features. In the second phase the signature is divided into 40 blocks from each of the four corners of the signature to generate 40 angular features. Totally 168 angular features are extracted from phase one and two to verify the signature. The centers of signature are compared using correlation and the distance between the angular features of the genuine and test signatures is computed. The correlation matching score and distance matching score of the signature are fused to verify the authenticity. A mathematical model is proposed to further optimize the results. It is observed that the proposed model has better FAR, FRR and EER values compared to the existing algorithms

A Secure Image Steganography using LSB, DCT and Compression Techniques on Raw Images

Steganography is an important area of research in recent years involving a number of applications. It is the science of embedding information into the cover image viz., text, video, and image (payload) without causing statistically significant modification to the cover image. The modern secure image steganography presents a challenging task of transferring the embedded information to the destination without being detected. In this paper we present an image based steganography that combines Least Significant Bit(LSB), Discrete Cosine Transform(DCT), and compression techniques on raw images to enhance the security of the payload. Initially, the LSB algorithm is used to embed the payload bits into the cover image to derive the stego-image. The stego-image is transformed from spatial domain to the frequency domain using DCT. Finally quantization and runlength coding algorithms are used for compressing the stego-image to enhance its security. It is observed that secure images with low MSE and BER are transferred without using any password, in comparison with earlier works

Zone Based Transmissions for Homogeneous Wireless Sensor Networks

—Wireless Sensor Network is a set of sensors deployed in the area of interest, for the purpose of monitoring physical or environmental conditions. Due to limited battery capacity of sensors, Wireless Sensor Networks have limited lifetime. A large number of sensors deployed in a circular grid, sending the sensed data to base station located at the center are considered and the parameters of interest are monitored. This paper proposes three algorithms to enhance the lifetime, reliability and throughput of the Wireless Sensor Network. The first two algorithms Reliable Zone Based Transmission (RZBT) and Reliable Circular Transmission (RCT) reschedule the packet transmission time of the sensor nodes, to reduce the loss of packets and ensures reliability of network functioning. The third algorithm Energy Efficient Reliable Transmission (EERT) reduces the number of transmissions, without the loss of data, thus extending lifetime of the network. Simulation results prove that 1) RCT outperforms conventional DiReCt Transmission (DRCT) and RZBT with respect to throughput and 2) EERT reduces the packets transmitted in each round, thus improves the lifetime of the sensor node and the network

Maximizing Efficiency of Large Scale Homogeneous Wireless Sensor Networks

Wireless Sensor Networks is a set of sensors deployed in the area of interest, for the purpose of monitoring physical or environmental conditions. Due to limited battery capacity of sensors, Wireless Sensor Networks have limited lifetime. A large number of sensors deployed in a circular grid, sending the sensed data to base station located at the center are considered and the parameters of interest are monitored. This paper proposes two algorithms to enhance the lifetime, reliability and throughput of the Wireless Sensor Network. The first algorithm Reliable Zone Based Transmission (RZBT) reschedules the packet transmission time of the sensor nodes, to reduce the loss of packets and ensures reliability of network functioning. The second algorithm Energy Efficient Reduced Transmission (EERT) reduces the number of transmissions, without the loss of data, thus extending lifetime of the network. Simulation results prove that RZBT outperforms conventional DiReCT Transmission (DRCT) and EERT reduces the packets transmitted in each round, thus improves the lifetime of the sensor node and the network

Zone Based Transmissions for Homogeneous Wireless Sensor Networks

Wireless Sensor Network is a set of sensors deployed in the area of interest, for the purpose of monitoring physical or environmental conditions. Due to limited battery capacity of sensors, Wireless Sensor Networks have limited lifetime. A large number of sensors deployed in a circular grid, sending the sensed data to base station located at the center are considered and the parameters of interest are monitored. This paper proposes three algorithms to enhance the lifetime, reliability and throughput of the Wireless Sensor Network. The first two algorithms Reliable Zone Based Transmission (RZBT) and Reliable Circular Transmission (RCT) reschedule the packet transmission time of the sensor nodes, to reduce the loss of packets and ensures reliability of network functioning. The third algorithm Energy Efficient Reliable Transmission (EERT) reduces the number of transmissions, without the loss of data, thus extending lifetime of the network. Simulation results prove that 1) RCT outperforms conventional DiReCt Transmission (DRCT) and RZBT with respect to throughput and 2) EERT reduces the packets transmitted in each round, thus improves the lifetime of the sensor node and the network