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Throughput optimization for multirate multicasting through association control in ieee 802.11 wlan 1

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14th EAI International Conference on Heterogeneous Networking for Quality, Reliability, Security and Robustness, Qshine 2018

作者： Bhaumick, Dhrubajyoti Ghosh, Sasthi C. Advanced Computing and Microelectronics Unit Indian Statistical Institute 203 B. T. Road KolkataWest Bengal700108 India

ISBN: (数字)9783030144135

ISBN: (纸本)9783030144128

Multicasting in wireless local area network is an efficient way to deliver message from a source user to a specified group of destination users simultaneously. In unirate multicasting, all users belonging to a particular group receive their services at the same basic rate. This may underutilize network resources as users requirements are generally heterogeneous in nature. To resolve this limitation, multirate multicasting is introduced, where different users belonging to a particular group may receive their services at different rates. Often dense deployment of access points (APs) is required for coverage and capacity improvement. Thus an station (STA) may come under the coverage range of several APs and hence there may exists many possible associations between the STAs and the APs. Hence finding an efficient association is very important as individual throughput of the STAs as well as the overall system throughput depend on it. We have developed an efficient algorithm to find an appropriate association for multirate multicasting. The objective is to maximize overall system throughput while respecting the user fairness. Through simulations, we have evaluated and compared the performance of our proposed algorithm with other well-known metrics such as received signal strength indicator, minimum hop-distance, in-range STA number and normalized cost. Results show that the proposed algorithm significantly improves the overall system throughput in comparison to these metrics. © ICST Institute for Computer Sciences, Social Informatics and Telecommunications Engineering 2019.

关键词： Multicasting

Local relay selection in presence of dynamic obstacles in millimeter wave D2D communication

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arXiv 2020年

作者： Singh, Durgesh Chattopadhyay, Arpan Ghosh, Sasthi C. Advanced Computing & Microelectronics Unit Indian Statistical Institute Kolkata700108 India Department of Electrical Engineering Indian Institute of Technology Delhi India

Blockage due to obstacles in millimeter wave (mmWave) device to device (D2D) communication is a prominent problem due to their severe penetration losses. Potential user equipments (UEs) in vicinity of the source UE must be explored in order to select a new relay when the current link gets blocked. However, dynamic obstacles are not known in advance and thus may cause unpredictable fluctuations to D2D channel quality causing newly selected relay link also to be susceptible to blockage. This might cause frequent relay switching leading to call drops and high energy consumption. We have proposed the idea of reducing frequency in relay exploration and switching and thus average end-to-end delay (in seconds) at the expense of additional exploration time units (few milliseconds) during beam alignment. We seek to learn the uncertainty in D2D link qualities by modeling the problem as finite horizon partially observable Markov decision process (POMDP) framework locally at each UE. We have derived an optimal threshold policy which maps the state to set of actions. We then give a simplified and easy to implement stationary threshold policy which counts the number of successive acknowledgment successes/failures for making decisions of selecting or not selecting a given relay locally. Through extensive simulation, we validate our theoretical findings and demonstrate that our approach captures the tradeoff between average exploration time and average end-to-end (E2E) delay in presence of dynamic obstacles. Copyright © 2020, The Authors. All rights reserved.

关键词： Markov processes

An empirical study of incremental learning in neural network with noisy training set

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arXiv 2020年

作者： Chatterjee, Atrayee Ganguly, Shovik Bhoumik, Debasmita Majumdar, Ritajit Asutosh College University of Calcutta Lexmark International India Pvt. Ltd Advanced Computing and Microelectronics Unit Indian Statistical Institute Kolkata India

The notion of incremental learning is to train an ANN algorithm in stages, as and when newer training data arrives. Incremental learning is becoming widespread in recent times with the advent of deep learning. Noise in the training data reduces the accuracy of the algorithm. In this paper, we make an empirical study of the effect of noise in the training phase. We numerically show that the accuracy of the algorithm is dependent more on the location of the error than the percentage of error. Using Perceptron, Feed Forward Neural Network and Radial Basis Function Neural Network, we show that for the same percentage of error, the accuracy of the algorithm significantly varies with the location of error. Furthermore, our results show that the dependence of the accuracy with the location of error is independent of the algorithm. However, the slope of the degradation curve decreases with more sophisticated algorithms. Copyright © 2020, The Authors. All rights reserved.

关键词： Errors

Scalable and Fair Resource Sharing Among 5G D2D Users and Legacy 4G Users: A Game Theoretic Approach

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Scalable and Fair Resource Sharing Among 5G D2D Users and Le...

International Communication Systems and Networks and Workshops, COMSNETS

作者： Sreetama Mukherjee Sasthi C. Ghosh Microsoft R&D Pvt. Ltd. Hyderabad India Advanced Computing and Microelectronics Unit Indian Statistical Institute Kolkata India

ISBN: (数字)9781728131870

ISBN: (纸本)9781728131887

We propose a game theoretic approach to the problem of resource allocation in 5G device to device (D2D) communications underlaying cellular networks, where modern 5G D2D users (DUs) share channel resources of legacy 4G cellular users (CUs). Though such sharing improves scalability as more and more users can be served, the individual throughput obtained by a CU may get reduced when its channel resource is shared by a DU pair. Thus our aim is to increase the overall system throughput while ensuring effective user fairness among the DUs and CUs served. Our approach provides a tradeoff between the two objectives thereby ensuring no legacy CUs are compromised heavily while encouraging modern DUs. We have addressed this fairness problem by thresholding the reduction of the throughput of a CU with respect to its ideal throughput if not reused. We have proposed a game theoretic model in order to make strategic decision for selecting the preferred action configuration in order to meet this objective. Together with this game model and a validation process, we aim to improve scalability, overall system throughput without compromising on the fairness of the users. We have also compared the user fairness achieved by our approach with an existing approach to demonstrate the effectiveness of our game theoretic approach.

关键词： Copper Throughput Games Resource management Device-to-device communication Interference 5G mobile communication

Strong edge coloring of Cayley graphs and some product graphs

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arXiv 2021年

作者： Dara, Suresh Mishra, Suchismita Narayanan, Narayanan Tuza, Zsolt Department of Mathematics School of Advanced Sciences VIT Bhopal University Kothri Kalan Sehore466114 India Advanced Computing and Microelectronics Unit Indian Statistical Institute Kolkata700108 India Department of Mathematics Indian Institute of Technology Madras Chennai600036 India Alfréd Rényi Institute of Mathematics Budapest Hungary University of Pannonia Veszprém Hungary

A strong edge coloring of a graph G is a proper edge coloring of G such that every color class is an induced matching. The minimum number of colors required is termed the strong chromatic index. In this paper we determine the exact value of the strong chromatic index of all unitary Cayley graphs. Our investigations reveal an underlying product structure from which the unitary Cayley graphs emerge. We then go on to give tight bounds for the strong chromatic index of the Cartesian product of two trees, including an exact formula for the product in the case of stars. Further, we give bounds for the strong chromatic index of the product of a tree with a cycle. For any tree, those bounds may differ from the actual value only by not more than a small additive constant (at most 2 for even cycles and at most 5 for odd cycles), moreover they yield the exact value when the length of the cycle is divisible by 4. Copyright © 2021, The Authors. All rights reserved.

关键词： Forestry

Prediction of the final rank of Players in PUBG with the optimal number of features

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arXiv 2021年

作者： Sen, Diptakshi Roy, Rupam Kumar Majumdar, Ritajit Chatterjee, Kingshuk Ganguly, Debayan Department of Computer Science and Engineering University of Calcutta India Advanced Computing and Microelectronics Unit Indian Statistical Institute Kolkata India Department of Computer Science and Engineering Government College of Engineering and Ceramic Technology India Department of Computer Science and Engineering Government College of Engineering and Leather Technology India

PUBG is an online video game that has become very popular among the youths in recent years. Final rank, which indicates the performance of a player, is one of the most important feature for this game. This paper focuses on predicting the final rank of the players based on their skills and abilities. In this paper we have used different machine learning algorithms to predict the final rank of the players on a dataset obtained from kaggle which has 29 features. Using the correlation heatmap,we have varied the number of features used for the model. Out of these models GBR and LGBM have given the best result with the accuracy of 91.63% and 91.26% respectively for 14 features and the accuracy of 90.54% and 90.01% for 8 features. Although the accuracy of the models with 14 features is slightly better than 8 features, the empirical time taken by 8 features is 1.4x lesser than 14 features for LGBM and 1.5x lesser for GBR. Furthermore, reducing the number of features any more significantly hampers the performance of all the ML models. Therefore, we conclude that 8 is the optimal number of features that can be used to predict the final rank of a player in PUBG with high accuracy and low run-time. © 2021, CC0.

关键词： Forecasting

Asymptotically Improved Circuit for d-ary Grover's Algorithm with advanced Decomposition of n-qudit Toffoli Gate

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arXiv 2020年

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

The progress in building quantum computers to execute quantum algorithms has recently been remarkable. Grover's search algorithm in a binary quantum system provides considerable speed-up over classical paradigm. Further, Grover's algorithm can be extended to a d-ary (qudit) quantum system for utilizing the advantage of larger state space, which helps to reduce the run-time of the algorithm as compared to the traditional binary quantum systems. In a qudit quantum system, an n-qudit Toffoli gate plays a significant role in the accurate implementation of Grover's algorithm. In this article, a generalized n-qudit Toffoli gate has been realized using higher dimensional qudits to attain a logarithmic depth decomposition without ancilla qudit. The circuit for Grover's algorithm has then been designed for any d-ary quantum system, where d ≥ 2, with the proposed n-qudit Toffoli gate to obtain optimized depth compared to earlier approaches. The technique for decomposing an n-qudit Toffoli gate requires access to two immediately higher energy levels, making the design susceptible to errors. Nevertheless, we show that the percentage decrease in the probability of error is significant as we have reduced both gate count and circuit depth as compared to that in state-of-the-art works. © 2020, CC BY.

关键词： Quantum optics

Optimal Error Correcting Code For Ternary Quantum Systems

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arXiv 2019年

作者： Majumdar, Ritajit Sur-Kolay, Susmita Advanced Computing & Microelectronics Unit Indian Statistical Institute India

Multi-valued quantum systems can store more information than binary ones for a given number of quantum states. For reliable operation of multi-valued quantum systems, error correction is mandated. In this paper, we propose a 5-qutrit quantum error correcting code and provide its stabilizer formulation. Since 5 qutrits are necessary to correct a single error, our proposed code is optimal in the number of qutrits. We prove that the error model considered in this paper spans the entire (3 × 3) operator space. Therefore, our proposed code can correct any single error on the codeword. This code outperforms the previous 9-qutrit code in (i) the number of qutrits required for encoding, (ii) our code can correct any arbitrary (3 × 3) error, (ii) our code can readily correct bit errors in a single step as opposed to the two-step correction used previously, and (iii) phase error correction does not require correcting individual subspaces. Copyright © 2019, The Authors. All rights reserved.

关键词： Many valued logics

Minimal degenerate CSS quantum code with low cost circuit

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arXiv 2019年

作者： Majumdar, Ritajit Sur-Kolay, Susmita Advanced Computing and Microelectronics Unit Indian Statistical Institute Kolkata India

Error correction is of utmost necessity for large-scale quantum computing. Quantum error correcting codes can be degenerate, if more than one type of error can map the input state to the same error state. In this paper, we propose a 6-qubit degenerate CSS code. We show that our proposed code can correct a single bit flip error, but arbitrarily many phase flip errors occurring on the codeword. Furthermore, it follows from a bound on CSS codes that the proposed code is the minimal binary CSS code which can encode a single qubit of information. We also perform a comparative study of the gate count required for a fault tolerant decomposition of the error correction circuit for the proposed code, with that for the existing 9-qubit, 7-qubit and 5-qubit binary QEC codes. Our results show, on an average over the different technologies a savings of 98.14% in the gate count for the proposed code over that for the 5-qubit code. Significant improvement of around 50% in gate count is also obtained when compared to those for the 9-qubit and 7-qubit codes. Copyright © 2019, The Authors. All rights reserved.

关键词： Error correction