vatsala sharma - Profile on Academia.edu (original) (raw)

Papers by vatsala sharma

Journal of Scientific Research, 2020

Cognitive Radio is a boon to efficient utilization of spectrum to meet the demand of next generat... more Cognitive Radio is a boon to efficient utilization of spectrum to meet the demand of next generation. Spectrum Sensing (SS) is an active research area, essential to meet the requirement of efficient spectrum utilization as it detects the vacant bands. This paper develops a Hybrid Blind Detection (HBD) technique for cooperative spectrum sensing which combines the Energy Detector (ED) and the Anti-Eigen Value Detection (AVD) techniques together to enhance the detection accuracy of a cognitive radio. Collaboration among the cognitive users is achieved to reduce the error and hard fusion based detection is implemented to detect the existence of primary user. The detection accuracy of the design is evaluated with respect to detection probabilities and the results are examined for improvements with the traditional two stage detection techniques. Fusion rules for the cooperative environment are implemented and compared to detect majority rule suitable for the proposed design.

Orthogonal frequency division multiplexing (OFDM) is a multicarrier modulation technique which us... more Orthogonal frequency division multiplexing (OFDM) is a multicarrier modulation technique which uses orthogonal subcarriers to convey information. Orthogonal frequency division multiplexing (OFDM) has been adopted as a standard for various high data rate wireless communication systems due to the high spectral bandwidth efficiency, robustness to frequency selective fading channels, well suited for mimo technology, Facilitate frequency-domain scheduling supports flexible bandwidth deployment etc. However, implementation of the OFDM system entails several difficulties. One of the major drawbacks is the high peak-to-average power ratio (PAPR) problem in multicarrier transmission system which leads to power inefficiency in RF section of the transmitter, inter carrier interference, high out-of-band radiation, and bit error rate performance degradation. It is preferred to have a minimum PAPR, as it will allow a higher average power to be transmitted for a fixed peak power; and thus, improvi...

Gorrochategui's book is a revised and updated translation of the Spanish edition (Spanish Ministr... more Gorrochategui's book is a revised and updated translation of the Spanish edition (Spanish Ministry of Defence, 2011). It sheds new light on an obscure, but fundamental, episode of the undeclared Anglo-Spanish War (1585-1604) that took place a year after the Spanish Armada. Interestingly, although Queen Elizabeth I was at first intentionally misinformed about this, once she knew the grim reality, she silenced it. The Queen prohibited any publication about the English Armada (also known as the Counter-Armada or Drake-Norris expedition) trying, successfully, to hide the disastrous result suffered by the English in that military campaign on the Iberian mainland. Only a few propaganda pamphlets were published in order to hide the truth, treating real but unfavorable facts as false rumors and instead showing a false aftermath of the campaign favorable to the English. According to the author, these pamphlets -the first by Anthony Wingfield (1) -were taken for reliable sources by British historians. Gorrochategui's thesis is that little attention has been paid to the Counter-Armada by historians, particularly in the English-speaking world. The author contrasts this fact with the vast literature produced on the Spanish Armada. There are a few exceptions: for instance, the British Hispanist Martin A. S. Hume (2) dedicated a full chapter to the Counter-Armada in his work The year after the Armada (1896). Hume was the first to proclaim the importance of that campaign previously consigned to oblivion: 'The story of this ill-starred expedition is usually disposed of in a few lines by English historians, although it success would have completely changed the status of England on the Continent'. Gorrochategui goes further: he thinks that with Portugal under English control, it would have opened new horizons for England in the Americas, considering Portuguese territories overseas. It is also worth pointing out the good job done by R. B. Wernham (3) in gathering the English sources of the Drake-Norris expedition in a single volume. Furthermore, the English Armada episode becomes crucial when considering that British historiography used -particularly in the Victorian era -the failure of the previous Spanish Armada to build a national myth around it. Historical facts were transformed into a self-interested version describing a sort of knock-out blow

Real-Time Implementation of Enhanced Energy-Based Detection Technique

A Literature Review on Spectrum Sensing in Cognitive Radio Applications

2018 Second International Conference on Intelligent Computing and Control Systems (ICICCS), 2018

Cognitive radio is a promising technology to meet the requirements of efficient usage of limited ... more Cognitive radio is a promising technology to meet the requirements of efficient usage of limited available frequency spectrum for next generation technology and demand for high data transmission. Cognitive radio technology requires detection of primary user signals for dynamic allocation of spectrum hole to secondary users. Spectrum sensing is an important function and an active research area in this regard. In this paper, a literature review of spectrum sensing is discussed, presenting different research domains of spectrum sensing for cognitive radio networks. System models with different modelling techniques are explained that can implement spectrum sensing. It also includes a brief summary of research challenges associated with spectrum sensing. The main subject of this paper is classification of spectrum sensing technique based on number of users, their comparison and future scope of research. Finally, we present current wireless standards that employ spectrum sensing and hardware platforms that can implement spectrum sensing algorithms in real time environment.

Journal of scientific research, 2020

Most of the conventional spectrum sensing algorithms are based on cognition of transmitting signa... more Most of the conventional spectrum sensing algorithms are based on cognition of transmitting signal features. The general approach for utilizing this cognition property is by bearing some information of the signal being transmitted. At the receiver end the detector obtains final decision explaining the existence of the signal in a certain specific spectrum band it utilizes for transmission. Moreover, in order to ameliorate the detection accuracy for a fixed value of false alarm probability is a dispute to maximum spectrum detection approaches. In this paper, we present a reliable optimal hybrid spectrum sensing scheme (ROHSS) based on energy detection for cognitive radio network. The proposed two stage ROHSS algorithm implements two detectors acting simultaneously corresponding to signals containing high and low signal to noise ratio. In first stage, an enhanced energy detector (EED) is used for the high Signal to noise ratio and an anti eigenvalue-based sensor detecting the signals with low signal to noise ratio. In second stage, student-teacher neural network (STNN) based sensor takes advantage of approximated eigen values of the transmitted signal and obtains a result regarding the existence of the signal. The main objective of the developed ROHSS algorithm is to detect the available frequency slots and allocated them to the cognitive users immediately in order to minimize the delay because of the efficient performance of the decision fusion method. The proposed ROHSS algorithm is analyzed and the performance is compared with the available sensing algorithms.

Design & Implementation of High speed Multipliers

ijera.com

Orthogonal Frequency Division Multiplexing (OFDM) is one well-known scheme, which has recently be... more Orthogonal Frequency Division Multiplexing (OFDM) is one well-known scheme, which has recently become a preferred choice for parallel-data-transmission which reduces the influence of multipath fading and avoids the use of complex equalizers. ...

CMOS Design of Pulse Processing ASIC for Radiation Detection

2018 Second International Conference on Inventive Communication and Computational Technologies (ICICCT), 2018

This paper presents the design & development of an 36 channel Pulse Processing ASIC using 0.3... more This paper presents the design & development of an 36 channel Pulse Processing ASIC using 0.35µm mixed CMOS technology for radiation detection in high energy physics experiments. The benefits of CMOS technology in nuclear instrumentation has surpassed the expectation due to advancement of technology, emerging detectors, readouts data rates and very important radiation hardness with benefits of low power and high density of electronics. The Pulse Processing ASIC intended to use with silicon pad detectors find application in high energy physics experiments for detecting nuclear radiations and converting the charge into electrical signals. The methodology of design includes circuit design and its optimization using public domain CAD tool.

International Journal of Engineering Research and

Rainwater harvesting is the process to store the rain water in containers before the rain water g... more Rainwater harvesting is the process to store the rain water in containers before the rain water goes beneath the ground and recharges the underground water table. This paper proposes the design of smart water management system based on Arduino as an IoT application. In the proposed design, once water is collected in ground tank, the ultrasonic sensor is used to sense the level of water. The sensed information is updated on an android application through which user can visualize the water level on a smartphone. According to the level of water in the tank, the motor functioning is controlled, when water reaches near high level of underground tank, motor will be turned on through Blynk application on smartphone to transfer the water in the ground tank to main tank and when main tank is about to fill up it will turn off automatically. When soil of the garden is dry, the soil moisture sensor senses the dryness in soil and automatically start the water pump and water flow through main tank and reach the soil of garden then motor is automatically switched off. Storing the rainwater reduces the surface runoff. This also reduces the surface erosion. By capturing rainwater in reservoirs, the flood problem in large rainfalls is also diminished.