Volume 30, Issue 1, April 2015

Blocking probability minimization in WDM with optimal placement of wavelength converters using ETGA [Full Text]

Ramya.S and Dr Indumathi T.S

Abstract— Wavelength division multiplexing technology has offered to exploit the wide bandwidth available in optical fibres, but also introduced new complexities in the routing problem. In this context, the wavelength converter allocation problem has become a key factor to minimize blocking probability. In this research we have given attention to minimizing blocking probability for given number of converters by providing its optimal placement in network. This work proposes a variation in conventional genetic algorithm by providing the elitism in tournament selection process. Extensive simulations show promising results in the sense that our algorithm generates the trade-off curve between blocking and the number of converters needed and outperforms conventional genetic algorithm approach. 

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Broadband Pulse shapes for PAPR Mitigation Technique [Full Text]

Ashwini Saykar and Debashis Adhikari

Abstract—The desire for higher data rates of transmission has resulted in the evolution of many new communication technologies over the years. Orthogonal Frequency Division Multiplexing (OFDM) is one such technology which is capable of achieving a high rate system. Although OFDM has many advantages of being a bandwidth efficient and high rate system, the problem of peak to average power ratio (PAPR) has resulted in a considerable disadvantage to this technology. In this paper we discuss a pulse shaping method to reduce the PAPR. Few broadband pulse shapes are analysed that can be used to modulate the sub-carrier frequencies. It is established that PSWF based pulses could lead to minimize the problem of PAPR.