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Aashish Mathur

Bio: Aashish Mathur is an academic researcher from Indian Institute of Technology, Jodhpur. The author has contributed to research in topics: Fading & Bit error rate. The author has an hindex of 12, co-authored 35 publications receiving 512 citations. Previous affiliations of Aashish Mathur include Birla Institute of Technology and Science & Indian Institutes of Technology.

Papers
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Journal ArticleDOI
TL;DR: In this article, the bit error rate (BER) performance of a free space optical (FSO) communication system was evaluated in the presence of amplified spontaneous emission (ASE) noise under weak, moderate to strong, and very strong atmospheric turbulence regimes and PEs.
Abstract: The performance of a free space optical (FSO) communication system is significantly affected by various atmospheric turbulence conditions and pointing errors (PEs) apart from the additive noise, which is assumed to be Gaussian Optical pre-amplifiers are an essential component of FSO systems for improving the receiver sensitivity However, optical pre-amplification results in amplified spontaneous emission (ASE), which dominates the receiver thermal and shot noises The square law photodetection process at the receiver in a FSO system necessitates the consideration of chi-square statistics for the decision variable contrary to the Gaussian approximation that is widely used in the literature In this paper, we evaluate the bit error rate (BER) performance of a FSO system assuming non-return-to-zero on–off keying modulation in the presence of ASE noise under weak, moderate to strong, and very strong atmospheric turbulence regimes and PEs We also derive asymptotic BER expressions for the considered FSO system for large values of the signal-to-noise ratio in terms of simple elementary functions Further insight into the system is provided by performing a diversity analysis

43 citations

Journal ArticleDOI
TL;DR: In this paper, the secrecy performance of the classic Wyner's wiretap model, where the main and eavesdropper channels are modeled by a general and versatile $\alpha $ - $\eta$ - $\kappa $ - ''mu $ fading model'' was analyzed.
Abstract: In this letter, we study the secrecy performance of the classic Wyner’s wiretap model, where the main and eavesdropper channels are modeled by a general and versatile $\alpha $ - $\eta $ - $\kappa $ - $\mu $ fading model. Novel and exact expressions of the average secrecy capacity and secrecy outage probability have been derived. Previous results on physical layer security can be obtained through our newly derived expressions by specializing the model parameters. More importantly, the derived results are also applicable for the secrecy performance analysis of some field measurements (e.g., in millimeter wave communications), which cannot be analyzed by previous results.

42 citations

Journal ArticleDOI
TL;DR: A maximum likelihood receiver of binary phase shift keying signals over Nakagami-m distributed additive noise in power line communication system is derived.
Abstract: In this letter, we derive a maximum likelihood receiver of binary phase shift keying signals over Nakagami- $m$ distributed additive noise in power line communication system. The decision variable is characterized by using copula approach. The analytical average bit error rate of the considered scheme is numerically evaluated by using the cumulative distribution function of the decision variable. It is shown by simulations that the proposed receiver performs significantly better than an existing suboptimal receiver.

38 citations

Journal ArticleDOI
TL;DR: It is shown through numerical results that RIS-based dual-hop mixed FSO-RF system provide a significant performance enhancement in comparison to a traditional dual-hops mixed FOsO- RF system even in presence of CCI.
Abstract: Reconfigurable intelligent surface (RIS) is an emerging technology that can achieve reconfigurable radio propagation environments for beyond 5G/6G wireless systems by smartly tuning the signal reflection via a large number of low-cost passive reflecting elements In this letter, we investigate the effect of co-channel interference (CCI) on RIS-based dual-hop mixed free-space optical (FSO)-radio frequency (RF) communication systems The source node, equipped with multiple FSO apertures, transmits subcarrier intensity modulated symbols on the FSO link subjected to Gamma-Gamma (GG) distributed atmospheric turbulence with pointing errors (PEs) It is assumed that the relay-RIS and RIS-destination links follow Rayleigh distribution The destination node is corrupted by multiple CCI (each following Rayleigh distribution) The performance of the considered system is evaluated by deriving novel closed-form expressions for the outage probability (OP) and bit error rate (BER) It is shown through numerical results that RIS-based dual-hop mixed FSO-RF system provide a significant performance enhancement in comparison to a traditional dual-hop mixed FSO-RF system even in presence of CCI

36 citations

Journal ArticleDOI
TL;DR: Analysis of the physical layer secrecy (PLS) performance of a hybrid free space optical and radio frequency (FSO/RF) communication system under a modified selection combining scheme reveals useful insights into the performance of the investigated mixed system.

34 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: An exhaustive review of state-of-the-art research activity on PLS in satellite communications, which is categorize by different architectures including land mobile satellite communication networks, hybrid satellite-terrestrial relay networks, and satellite- terrestrial integrated networks.
Abstract: Research and processing development on satellite communications has strongly re-emerged in recent years. Following the prosperity of various wireless services provided by satellite communications, the security issue has raised growing concerns since the space information network is susceptible to be eavesdropped by illegal adversaries in such a large-scale wireless network. Recently, the physical-layer security (PLS) has emerged as an alternative security paradigm that explores the randomness of the wireless channel to achieve confidentiality and authentication. The success story of the PLS technique now spans a decade and thrives to provide a layer of defense in satellite communications. With this position, a comprehensive survey of satellite communications is conducted in this article with an emphasis on PLS. We first briefly introduce essential background and the view of the satellite Internet of Things (IoT), as well as discuss related research challenges faced by the emerging integrated network architecture. Then, we revisit the most popular satellite channel model influenced by many factors and list the commonly used secrecy performance metrics. Also, we provide an exhaustive review of state-of-the-art research activity on PLS in satellite communications, which we categorize by different architectures including land mobile satellite communication networks, hybrid satellite-terrestrial relay networks, and satellite-terrestrial integrated networks. In addition, a number of open research problems are identified as possible future research directions.

139 citations

Journal ArticleDOI
TL;DR: It is shown that HPWC and HSRC offer a more reliable data transmission path when compared to power line or wireless system working alone, and a connection between the capillarity of IoT and the communication infrastructure provided by SG.
Abstract: This paper outlines important characteristics of hybrid power line/wireless data communication system for smart grid (SG) and Internet of Things (IoT) applications. Moreover, we discuss the hybrid systems advantages in comparison to nonhybrid ones. These advantages are demonstrated not only in the technical point of view, but also in the infrastructural perspective. Also, we highlight a connection between the capillarity of IoT and the communication infrastructure provided by SG. Furthermore, we address the environmental influence on wireless and power line communications. Additionally, we present ergodic achievable data rate expressions for the hybrid power line/wireless channel (HPWC) and hybrid power line/wireless single-relay channel (HSRC) and provide performance analyses by considering four different cases, which are associated with the relative relay position in the single-relay channel model. Based on numerical results, we show that HPWC and HSRC offer a more reliable data transmission path when compared to power line or wireless system working alone.

127 citations

Journal ArticleDOI
TL;DR: The physical layer secrecy performance of a hybrid satellite and free-space optical (FSO) cooperative system is studied and it is found that with the AF with fixed gain scheme, the secrecy diversity order of the investigated system is only dependent on the channel characteristics of the FSO link and theFSO detection type, whereas the secrecy Diversity is zero when the relay node employs DF or AF with variable-gain schemes.
Abstract: In this paper, we study the physical layer secrecy performance of a hybrid satellite and free-space optical (FSO) cooperative system. The satellite links are assumed to follow the shadowed-Rician fading distribution, and the channel of the terrestrial link between the relay and destination is assumed to experience the gamma-gamma fading. For the FSO communications, the effects of different types of detection techniques (i.e., heterodyne detection and intensity modulation with direct detection) as well as the pointing error are considered. We derive exact analytical expressions for the average secrecy capacity and secrecy outage probability (SOP) for both cases of amplify-and-forward (AF) and decode-and-forward (DF) relaying. The asymptotic analysis for the SOP is also conducted to provide more insights on the impact of FSO and satellite channels on secrecy performance. It is found that with the AF with fixed gain scheme, the secrecy diversity order of the investigated system is only dependent on the channel characteristics of the FSO link and the FSO detection type, whereas the secrecy diversity is zero when the relay node employs DF or AF with variable-gain schemes.

104 citations

Proceedings ArticleDOI
25 May 2020
TL;DR: Performance of the system in terms of the secrecy capacity is affected by the location of the RIS-relay and the number of RIS cells, and the effect of other system parameters such as source power and eavesdropper distances are studied.
Abstract: This paper studies the physical layer security (PLS) of a vehicular network employing a reconfigurable intelligent surface (RIS). RIS technologies are emerging as an important paradigm for the realisation of smart radio environments, where large numbers of small, low-cost and passive elements, reflect the incident signal with an adjustable phase shift without requiring a dedicated energy source. Inspired by the promising potential of RIS-based transmission, we investigate two vehicular network system models: One with vehicle-to-vehicle communication with the source employing a RIS-based access point, and the other model in the form of a vehicular adhoc network (VANET), with a RIS-based relay deployed on a building. Both models assume the presence of an eavesdropper to investigate the average secrecy capacity of the considered systems. Monte-Carlo simulations are provided throughout to validate the results. The results show that performance of the system in terms of the secrecy capacity is affected by the location of the RIS-relay and the number of RIS cells. The effect of other system parameters such as source power and eavesdropper distances are also studied.

92 citations