Informatics Publishing Limited

R. Raja Kumar ¹, A. Sampath ¹, P. Indumathi ²

Affiliations
1 Mathematics Department, Sathyabama University, Chennai-119, IN
2 Electronics Engineering Department, MIT Campus, Anna University, Chennai, IN

Abstract

This paper proposes a Frequency Hopped Spread Spectrum (FHSS) communication system using chaos and its synchronization. The spread spectrum technique of frequency hopping uses pseudorandom number (PN) generator to produce a random sequence of frequencies. A new class of signature sequences for use in Frequency Hopped Spread Spectrum communication systems is proposed. In arriving at these sequences, the theory of chaos has been used. The correlation properties of these chaotic sequences are similar to random white noise. The numbers and lengths of chaotic sequences are not restricted like m sequences. The performances of chaotic sequences in multiple access communication are shown to be similar to that of PN sequences. Furthermore, due to their noise like appearance, chaotic sequences outperform PN sequences in low probability of intercept. In this method the spreading sequences change from one bit to the next in very random like fashion, causing undesired interception to be very difficult. The synchronization of the system is also proposed.

Keywords

Chaotic Sequences, Chaotic System, FHSS, PN Sequences, Synchronization.

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R. Raja Kumar ¹, A. Sampath ¹, P. Indumathi ²

Affiliations
1 Mathematics Department, Sathyabama University, Chennai-119, IN
2 Electronics Engineering Departments, MIT Campus, Anna University, Chennai, IN

Abstract

In this paper we examine one of the recently proposed chaotic image encryption algorithms, based on chaotic map lattices (CML). We also study and examine another algorithm that could satisfy expectations of efficiency and security in the case of digital colour image encryption. The proposed algorithm provides more security and secrecy to the colour digital images as compared to the security provided by the existing CML based algorithm suggested by Pisarchik. At the end, we show the results of a security analysis and a comparison of both schemes.

Keywords

Chaotic Map Lattice, Digital Image, Image Encryption, Security.

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A. Gangopadhyay ¹, A. Sampath ¹, B. Velury ², D. P. Sen Gupta ¹, D. R. Ahuja ¹

Affiliations
1 National Institute of Advanced Studies, IISc Campus, Bengaluru 560 012, IN
2 Power System Operation Corporation Limited, 29, Race Course Cross Road, Bengaluru 560 009, IN

Abstract

Karnataka suffers from chronic electricity shortages and daily load-shedding, which are expected to persist despite planned additions of conventional power. Using four illustrative scenarios based on different assumptions, we estimate the additional contributions wind and solar power sources could make to reduce these deficits by FY2022. The method developed estimates expected hourly deficits in FY2022 from projected unrestricted demands and expected availability from conventional sources. We estimate that additional 8000-8700 MW (11 BU) of wind and 3300-3500 MW (5 BU) of solar power would reduce the annual deficit by approximately three-fourths. A recommended pumped hydro storage facility will reduce the deficits further by 10% and help in meeting the daily peaks in demand.

Keywords

Conventional Energy Sources, Electricity Shortage, Pumped Hydro Storage, Wind and Solar Power.

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B. R. Srinivasan ¹, A. Sampath ²

Affiliations
1 Bharathidasan University, Tiruchirapalli— 620 023 Tamilnadu, IN
2 Sri Vasavi College, Erode-631 316, Tamihiadu, IN

Abstract

An Elementary Proof of the Prime Number theorem with a Remainder Term.

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