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Mobility tolerant broadcast in mobile ad hoc networks

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Lecture Notes in Computer Science (including subseries Lectu...

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) 2004年 3326卷 435-446页

作者： Srimani, Pradip K. Sinha, Bhabani P. Department of Computer Science Clemson University Clemson SC 29634-0974 United States Advanced Computing and Microelectronics Unit Indian Statistical Institute Calcutta 700108 India

A new deterministic broadcast protocol for an ad hoc network is proposed in this paper which avoids re-computation of the transmission schedule, even when the topology of the network changes due to the mobility of the nodes. The basic idea is to use a successive partitioning scheme by representing the identifier of each node (an integer) in an arbitrarily chosen radix system;the protocol then computes the specific time slots in which a particular node should transmit its message. The proposed protocol is simple, easy to implement and needs lesser broadcast time than that in [BBC99]. © Springer-Verlag Berlin Heidelberg 2004.

关键词： Mobile ad hoc networks

Efficient Bonded Channel Assignment in IEEE 802.11 WLAN with Heterogeneous Clients 2015

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Efficient Bonded Channel Assignment in IEEE 802.11 WLAN with...

13th International Conference on Advances in Mobile computing and Multimedia, MoMM 2015

作者： Tewari, Babul P. Ghosh, Sasthi C. Department of Computer Science and Engineering Dr. B. C. Roy Engineering College Durgapur 713 206 West-Bengal India Advanced Computing and Microelectronics Unit Indian Statistical Institute 203 B. T. Road Kolkata700 108 India

ISBN: (纸本)9781450334938

Channel bonding allows IEEE 802.11n clients to operate at a maximum rate of 300 Mbps which can significantly improve the network throughput. But at the same time it increases the co-channel interference to the nearby APs leading to a degradation of network throughput. The issue becomes more serious when the network consists of heterogeneous clients. An inappropriate assignment of bonded channels to the APs may penalize the legacy clients served by other APs. Furthermore, activating the APs with non-bonded channels only may also penalize the n clients. In both cases the network throughput may be compromised. In this paper we propose an efficient bonded channel assignment algorithm addressing how efficiently a bonded channel can be used together with non-bonded channels to maximize the network throughput. Through extensive simulation we have shown that the proposed approach is efficient enough in terms of both network throughput and client fairness. © 2015 ACM.

关键词： IEEE Standards

Improved bounds on the span of L(1, 2)-edge labeling of some infinite regular grids

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arXiv 2022年

作者： Bandopadhyay, Susobhan Ghosh, Sasthi C. Koley, Subhasis School Of Computer Sciences National Institute Of Science Education And Research Bhubaneswar India Advanced Computing And Microelectronics Unit Indian Statistical Institute Kolkata India

For two given nonnegative integers h and k, an L(h, k)-edge labeling of a graph G is the assignment of labels {0, 1,⋯, n} to the edges so that two edges having a common vertex are labeled with difference at least h and two edges not having any common vertex but having a common edge connecting them are labeled with difference at least k. The span λ′h,k(G) is the minimum n such that G admits an L(h, k)-edge labeling. Here our main focus is on finding λ′1,2(G) for L(1, 2)-edge labeling of infinite regular hexagonal (T3), square (T4), triangular (T6) and octagonal (T8) grids. It was known that 7 ≤ λ′1,2(T3) ≤ 8, 10 ≤ λ′1,2(T4) ≤ 11, 16 ≤ λ′1,2(T6) ≤ 20 and 25 ≤ λ′1,2(T8) ≤ 28. Here we settle two long standing open questions i.e. λ′1,2(T3) and λ′1,2(T4). We show λ′1,2(T3) = 7, λ′1,2(T4) = 11. We also improve the bound for T6and T8and prove λ′1,2(T6) ≥ 18, λ′1,2(T8) ≥ 26. © 2022, CC BY.

关键词： Graph theory

DCSK-based Waveform Design for Self-sustainable RIS-aided Noncoherent SWIPT

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arXiv 2024年

作者： Mukherjee, Priyadarshi Psomas, Constantinos Krikidis, Ioannis The Advanced Computing & Microelectronics Unit Indian Statistical Institute Kolkata India The Department of Electrical and Computer Engineering University of Cyprus Nicosia1678 Cyprus

This paper investigates the problem of transmit waveform design in the context of a chaotic signal-based self-sustainable reconfigurable intelligent surface (RIS)-aided system for simultaneous wireless information and power transfer (SWIPT). Specifically, we propose a differential chaos shift keying (DCSK)-based RIS-aided point-to-point set-up, where the RIS is partitioned into two non-overlapping surfaces. The elements of the first sub-surface perform energy harvesting (EH), which in turn, provide the required power to the other sub-surface operating in the information transfer (IT) mode. In this framework, by considering a generalized frequency-selective Nakagami-m fading scenario as well as the nonlinearities of the EH process, we derive closed-form analytical expressions for both the bit error rate (BER) at the receiver and the harvested power at the RIS. Our analysis demonstrates, that both these performance metrics depend on the parameters of the wireless channel, the transmit waveform design, and the number of reflecting elements at the RIS, which switch between the IT and EH modes, depending on the application requirements. Moreover, we show that, having more reflecting elements in the IT mode is not always beneficial and also, for a given acceptable BER, we derive a lower bound on the number of RIS elements that need to be operated in the EH mode. Furthermore, for a fixed RIS configuration, we investigate a trade-off between the achievable BER and the harvested power at the RIS and accordingly, we propose appropriate transmit waveform designs. Finally, our numerical results illustrate the importance of our intelligent DCSK-based waveform design on the considered framework. © 2024, CC BY-NC-ND.

关键词： Inductive power transmission

FAST 3D VOLUMETRIC IMAGE RECONSTRUCTION FROM 2D MRI SLICES BY PARALLEL PROCESSING

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arXiv 2023年

作者： Ghoshal, Somoballi Goswami, Shremoyee Chakrabarti, Amlan Sur-Kolay, Susmita A. K. Choudhury School of Information Technology University of Calcutta India Advanced Computing and Microelectronics Unit Indian Statistical Institute India

Magnetic Resonance Imaging (MRI) is a technology for non-invasive imaging of anatomical features in detail. It can help in functional analysis of organs of a specimen but it is very costly. In this work, methods for (i) virtual three-dimensional (3D) reconstruction from a single sequence of two-dimensional (2D) slices of MR images of a human spine and brain along a single axis, and (ii) generation of missing inter-slice data are proposed. Our approach helps in preserving the edges, shape, size, as well as the internal tissue structures of the object being captured. The sequence of original 2D slices along a single axis is divided into smaller equal sub-parts which are then reconstructed using edge preserved kriging interpolation to predict the missing slice information. In order to speed up the process of interpolation, we have used multiprocessing by carrying out the initial interpolation on parallel cores. From the 3D matrix thus formed, shearlet transform is applied to estimate the edges considering the 2D blocks along the Z axis, and to minimize the blurring effect using a proposed mean-median logic. Finally, for visualization, the sub-matrices are merged into a final 3D matrix. Next, the newly formed 3D matrix is split up into voxels and marching cubes method is applied to get the approximate 3D image for viewing. To the best of our knowledge it is a first of its kind approach based on kriging interpolation and multiprocessing for 3D reconstruction from 2D slices, and approximately 98.89% accuracy is achieved with respect to similarity metrics for image comparison. The time required for reconstruction has also been reduced by approximately 70% with multiprocessing even for a large input data set compared to that with single core processing. © 2023, CC BY.

关键词： Magnetic resonance imaging

Chaotic Waveform-based Signal Design for Noncoherent SWIPT Receivers

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arXiv 2023年

作者： Mukherjee, Priyadarshi Psomas, Constantinos Krikidis, Ioannis Advanced Computing & Microelectronics Unit Indian Statistical Institute Kolkata India Department of Electrical and Computer Engineering University of Cyprus Nicosia1678 Cyprus

This paper proposes a chaotic waveform-based multi-antenna receiver design for simultaneous wireless information and power transfer (SWIPT). Particularly, we present a differential chaos shift keying (DCSK)-based SWIPT multiantenna receiver architecture, where each antenna switches between information transfer (IT) and energy harvesting (EH) modes depending on the receiver’s requirements. We take into account a generalized frequency-selective Nakagami-m fading model as well as the nonlinearities of the EH process to derive closed-form analytical expressions for the associated bit error rate (BER) and the harvested direct current (DC), respectively. We show that, both depend on the parameters of the transmitted waveform and the number of receiver antennas being utilized in the IT and EH mode. We investigate a trade-off in terms of the BER and energy transfer by introducing a novel achievable ‘success rate - harvested energy’ region. Moreover, we demonstrate that energy and information transfer are two conflicting tasks and hence, a single waveform cannot be simultaneously optimal for both IT and EH. Accordingly, we propose appropriate transmit waveform designs based on the application specific requirements of acceptable BER or harvested DC or both. Numerical results demonstrate the importance of chaotic waveform-based signal design and its impact on the proposed receiver architecture. © 2023, CC BY-NC-SA.

关键词： Energy harvesting

Search of clustered marked states with lackadaisical quantum walks

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arXiv 2018年

作者： Saha, Amit Majumdar, Ritajit Saha, Debasri Chakrabarti, Amlan Sur-Kolay, Susmita A. K. Choudhury School of Information Technology University of Calcutta Advanced Computing & Microelectronics Unit Indian Statistical Institute Kolkata India

Nature of quantum walk in presence of multiple marked state has been studied by Nahimovs and Rivosh [8]. They have shown that if the marked states are arranged in a √k× √k cluster in a √N × √N grid, then to find a single marked state among the multiple ones, quantum walk requires Ω(√N − √k) time. In this paper, we show that using lackadaisical quantum walk with the weight of the self-loop as N(k+4b√2k c), where k is odd, the probability of finding a marked state increases by ∼ 0.2. Furthermore, we show that instead of applying the quantum walk O(k) times to find all the marked states, classical search in the vicinity of the marked state found after the first implementation of the quantum walk can find all the marked states in O(√k) time on average. Copyright © 2018, The Authors. All rights reserved.

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MAB based Network Selection mechanism for URLLC users in RIS assisted network

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MAB based Network Selection mechanism for URLLC users in RIS...

IEEE International Symposium on Network computing and Applications

作者： Souvik Deb Shankar Kumar Ghosh Sasthi C. Ghosh Advanced Computing & Microelectronics Unit Indian Statistical Institute Kolkata India Department of CSE Shiv Nadar Institution of Eminence Delhi NCR India

ISBN: (纸本)9798350397314

In this work, a network selection mechanism for re-configurable intelligent surface (RIS) assisted network has been proposed. The goal of the proposed mechanism is to select appropriate base station (BS) or BS-RIS pair to maximize user throughput while satisfying the delay and reliability constraints of uRLLC users. First, the network selection mechanism for RIS assisted network has been formulated as multi arm bandit (MAB) problem; Then, based on the formulation, a network selection strategy has been proposed. Finally, through extensive system level simulations, it has been shown that the proposed scheme outperforms the existing A3 handover scheme in terms of reliability and user throughput.

关键词： Integer programming Base stations Computational modeling Ultra reliable low latency communication Handover Throughput Delays

Quantum error correcting code for ternary logic

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arXiv 2018年

作者： Majumdar, Ritajit Basu, Saikat Ghosh, Shibashis Sur-Kolay, Susmita Advanced Computing & Microelectronics Unit Indian Statistical Institute India A. K. Choudhury School of Information Technology University of Calcutta India

Ternary quantum systems are being studied because these provide more computational state space per unit of information, known as qutrit. A qutrit has three basis states, thus a qubit may be considered as a special case of a qutrit where the coefficient of one of the basis states is zero. Hence both (2 × 2)-dimensional as well as (3 × 3)-dimensional Pauli errors can occur on qutrits. In this paper, we (i) explore the possible (2 × 2)-dimensional as well as (3 × 3)-dimensional Pauli errors in qutrits and show that any pairwise bit swap error can be expressed as a linear combination of shift errors and phase errors, (ii) propose a new type of error called quantum superposition error and show its equivalence to arbitrary rotation, (iii) formulate a nine qutrit code which can correct a single error in a qutrit, and (iv) provide its stabilizer and circuit realization. Copyright © 2018, The Authors. All rights reserved.

关键词： Errors