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Abhijit Bhowmick

Bio: Abhijit Bhowmick is an academic researcher from VIT University. The author has contributed to research in topics: Cognitive radio & Throughput (business). The author has an hindex of 10, co-authored 44 publications receiving 257 citations. Previous affiliations of Abhijit Bhowmick include Bengal College of Engineering & Technology & BCET Gurdaspur.

Papers published on a yearly basis

Papers
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Journal ArticleDOI
TL;DR: Novel analytical expressions for average harvested energy and average throughput are developed under an energy-harvesting-based cognitive radio (CR) system, which maximizes the harvested energy.
Abstract: In this letter, we analyze an energy-harvesting-based cognitive radio (CR) system. The CR system harvests energy from the radio frequency (RF) signal of primary user (PU) during sensing time as well as the transmission time of a detection cycle if PU is present. The CR accesses the spectrum band of PU opportunistically using the energy harvested over the frames with PU present, while maintaining a quality of service (QoS) constraint on PU in terms of a collision probability. An optimal sensing time is found, which maximizes the harvested energy. The performance is investigated in terms of harvested energy, outage probability, and throughput of the network. Novel analytical expressions for average harvested energy and average throughput are developed under such a scenario, which are validated by simulation.

50 citations

Journal ArticleDOI
TL;DR: A novel prediction based cooperative spectrum sensing scheme is investigated on the performance of an energy harvesting cognitive radio (CR) network to protect the quality of service (QoS) of primary user (PU) and to improve the utilization of spectrum holes.
Abstract: In this paper, a novel prediction based cooperative spectrum sensing scheme is investigated on the performance of an energy harvesting cognitive radio (CR) network. The spectrum sensing scheme is redesigned to protect the quality of service (QoS) of primary user (PU) and to improve the utilization of spectrum holes. The decision about the PU spectrum status and energy harvesting (RF and non-RF) of a CR node are based on prediction as well as sensing at individual CR level. We consider simultaneous spectrum sensing and energy harvesting scenario through the incorporation of an energy splitting device. A CR harvests from non-RF resources if both the decisions (decision of prediction and decision of spectrum sensing) do not match or if both the decisions match in favor of the absence of PU. On contrary, it harvests from RF resources while both the decisions match in favor of the presence of PU. A CR node transmits only if both decisions indicate the absence of PU. A CR user opportunistically uses the PU spectrum for its transmission purpose under a collision constraint. The collision constraint gives an extra protection to the QoS of PU on rearrival of PU. Novel analytical expressions for detection performance, harvested energy, and network throughput are developed. The impact of prediction and other network parameters such as number of detection frames, number of cooperative CR user, splitting parameter, collision probability on throughput performance is investigated. Improvement in spectrum reuse and energy penalty during harvesting is indicated. Impact of noise power estimation on the sensing performance is also studied.

43 citations

Journal ArticleDOI
TL;DR: It was observed that k nor increases as the signal power raise factor of IED increases or failed sensing probability decreases, and the agility of the network improves as the PU death rate increases.
Abstract: Performance of cooperative spectrum sensing in a cognitive radio (CR) network is investigated where each CR node uses an improved energy detector (IED) to sense the primary user (PU), and makes a local decision regarding the presence of PU using double thresholds (DTHs). The local hard decisions are combined at fusion centre (FC) to obtain the global decision. The advantage of a DTH-based system over a single threshold based one is, a CR node can opt for no decision when a decision variable lies in the fuzzy zone between two thresholds. Such censoring reduces the transmission overhead between CR and FC without significantly affecting the receiver operating characteristics. In this study, the performance of the abovementioned CR network has been assessed in terms of the average number of normalised transmitted sensing bits (k nor), the total error probability (P e,n ) and optimal number of CR users that ensures minimum Pe,n . It was observed that k nor increases as the signal power raise factor of IED increases or failed sensing probability decreases. Further, the agility of the network improves as the PU death rate increases. Impact of reporting channel on the sensing performance has also been indicated.

23 citations

Journal ArticleDOI
TL;DR: Two novel spectrum access schemes are proposed to enhance the performance of cognitive radio (CR) enabled secondary user (SU) in terms of throughput and outage probability in a CR network and are found to outperform the conventional schemes, interms of secondary performance.
Abstract: In this paper two novel spectrum access schemes, a hybrid spectrum access scheme (HSAS) and a modified hybrid spectrum access scheme (MHSAS) combining underlay and overlay, are proposed to enhance the performance of cognitive radio (CR) enabled secondary user (SU) in terms of throughput and outage probability in a CR network. The CR employs an energy detection to detect the presence of primary user (PU). If PU is sensed to be present, the CR employs an underlay scheme of co-existence while the CR works in an overlay mode if the PU is sensed to be absent. In underlay mode, the transmit power of CR is controlled so as to maintain the interference at PU receiver within a tolerable limit. An imperfect CSI of the interfering link between CR transmitter and PU receiver is assumed. In HSAS, CR transmits either in underlay scheme or in overlay scheme only during the transmission phase of the detection cycle whereas in MHSAS, the CR transmits for the entire frame including the sensing period of a detection cycle. Closed form analytical expressions for the throughput and outage of CR have been developed. Impact of several sensing parameters such as sensing time, channel estimation error, tolerable interference threshold, maximum allowable transmit power of CR is investigated. The impact of collision probability on the performance of CR network due to re-arrival of PU under proposed scheme is investigated. Furthermore the performances of the proposed schemes are also compared with the conventional i.e. only underlay or only overlay schemes. Our schemes are found to outperform the conventional schemes, in terms of secondary performance.

18 citations

Proceedings ArticleDOI
01 Dec 2015
TL;DR: A Novel analytical expressions of harvested energy and throughput are developed under harvesting of energy from combined RF signal and ambient sources, i.e., non-RF signal.
Abstract: In this paper the performance of a cognitive radio (CR)network is investigated under harvesting of energy from combined RF signal and ambient sources, i.e., non-RF signal. The CR harvests energy from ambient sources as well as from primary user (PU) signal depending on the sensing decision. The quality of service (QoS) of PU is protected in terms of collision probability. The performance has been investigated in terms of harvested energy, throughput and harvested energy left for next detection cycle with respect to different sensing parameters such as sensing channel SNR, collision probability and sensing time etc. A Novel analytical expressions of harvested energy and throughput are developed under such scenario.

15 citations


Cited by
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01 Jan 2016
TL;DR: The table of integrals series and products is universally compatible with any devices to read and is available in the book collection an online access to it is set as public so you can get it instantly.
Abstract: Thank you very much for downloading table of integrals series and products. Maybe you have knowledge that, people have look hundreds times for their chosen books like this table of integrals series and products, but end up in harmful downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some harmful virus inside their laptop. table of integrals series and products is available in our book collection an online access to it is set as public so you can get it instantly. Our book servers saves in multiple locations, allowing you to get the most less latency time to download any of our books like this one. Merely said, the table of integrals series and products is universally compatible with any devices to read.

4,085 citations

Journal ArticleDOI
TL;DR: A novel hybridization of Particle Swarm Optimization (PSO) with Gravitational Search Algorithm (GSA) called as Hybrid PSO-GSA is proposed to detect spectrum holes with improved energy utilization to improve the energy efficiency of the spectrum sensing.

67 citations

Journal ArticleDOI
TL;DR: The design, deployment, and test of a smart data gathering system for monitoring several parameters in aquaculture tanks using a wireless sensor network and the design of a conductivity sensor and a level sensor are presented.
Abstract: Summary The design of monitoring systems for marine areas has increased in the last years One of the many advantages of wireless sensor networks is the quick process in data acquisition The information from sensors can be processed, stored, and transmitted using protocols efficiently designed to energy saving and establishing the fastest routes The processing and storing of data can be very useful for taking intelligent decisions for improving the water quality The monitoring of water exchange in aquaculture tanks is very important to monitor the fish welfare Thus, this paper presents the design, deployment, and test of a smart data gathering system for monitoring several parameters in aquaculture tanks using a wireless sensor network The system based on a server is able to request and collect data from several nodes and store them in a database This information can be postprocessed to take efficient decisions The paper also presents the design of a conductivity sensor and a level sensor These sensors are installed in several aquaculture tanks The system was implemented using Flyport modules Finally, the data gathering system was tested in terms of consumed bandwidth and the delay Transmission Control Protocol (TCP) packets delivering data from the sensors

60 citations

Journal ArticleDOI
TL;DR: The impact of the cognitive user mobility on the performance of the improved energy detector is investigated and the statistics for the received signal are derived over various fading environments.
Abstract: A cooperative cognitive radio network (CRN) with improved energy detection-based spectrum sensing is analyzed in various fading scenarios. Generalized multipath (Nakagami- $m$ ) fading and enriched multipath (Nakagami- $q$ ) fading models are considered along with two other general fading distributions, i.e., $\kappa$ - $\mu$ and $\eta$ - $\mu$ distributions. For spectrum sensing, instead of conventional power 2-based detection method, the arbitrary power $p$ -based improved energy detector is used. The impact of the cognitive user mobility on the performance of the improved energy detector is investigated. Specifically, the statistics for the received signal are derived over various fading environments. The performance of the considered CRN system is evaluated in terms of probability of false alarm, probability of missed detection, and receiver operating characteristics (ROC) curves. Moreover, the area under the ROC curve is also obtained. Simulation results are provided to corroborate the theoretical results derived in this paper.

50 citations

Journal ArticleDOI
TL;DR: A novel prediction based cooperative spectrum sensing scheme is investigated on the performance of an energy harvesting cognitive radio (CR) network to protect the quality of service (QoS) of primary user (PU) and to improve the utilization of spectrum holes.
Abstract: In this paper, a novel prediction based cooperative spectrum sensing scheme is investigated on the performance of an energy harvesting cognitive radio (CR) network. The spectrum sensing scheme is redesigned to protect the quality of service (QoS) of primary user (PU) and to improve the utilization of spectrum holes. The decision about the PU spectrum status and energy harvesting (RF and non-RF) of a CR node are based on prediction as well as sensing at individual CR level. We consider simultaneous spectrum sensing and energy harvesting scenario through the incorporation of an energy splitting device. A CR harvests from non-RF resources if both the decisions (decision of prediction and decision of spectrum sensing) do not match or if both the decisions match in favor of the absence of PU. On contrary, it harvests from RF resources while both the decisions match in favor of the presence of PU. A CR node transmits only if both decisions indicate the absence of PU. A CR user opportunistically uses the PU spectrum for its transmission purpose under a collision constraint. The collision constraint gives an extra protection to the QoS of PU on rearrival of PU. Novel analytical expressions for detection performance, harvested energy, and network throughput are developed. The impact of prediction and other network parameters such as number of detection frames, number of cooperative CR user, splitting parameter, collision probability on throughput performance is investigated. Improvement in spectrum reuse and energy penalty during harvesting is indicated. Impact of noise power estimation on the sensing performance is also studied.

43 citations