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Abstract: Optics is a strong and potential candidate in the field of both communication and data processing because of its several inherent advantages. In digital communication the conversion of serial to parallel and parallel to serial data is very much essential for adopting some special modulation. In this communication the authors propose a new concept of developing an all-optical converter which converts a serial data to parallel one. For this purpose the authors use several optical logic gates specifically AND, NOT, NAND gates. Also an optical memory (Flip-Flop) circuit is used to do the processing. As it is known that, one Flip-Flop is required to store only one bit, hence, the number of Flip-Flops will be equal to the number of required data to be converted. Here, a two bit serial data is converted to the two bit parallel data and then the scheme is generalized for converting n bit serial data to parallel one. The main advantage of the scheme is that, it gives a super-fast processing speed which can be used in optical communication as well as in computation.

Abstract: Using the process of traffic grooming in optical networks, the whole bandwidth of the optical fibers is utilized by multiplexing and demultiplexing low-speed traffic streams onto high-speed wavelengths. In this article, a multiobjective genetic algorithm based technique for minimizing the cost of unidirectional SONET/WDM optical rings employing traffic grooming is presented. Two major cost components, viz., the number of SONET add/drop multiplexers (SADMs) and the grooming ratio needed for grooming low-speed traffic streams onto high-speed wavelengths have been optimized simultaneously. A well-known multiobjective genetic algorithm (NSGA-II) has been utilized as the underlying multiobjective optimization tool. The resultant set of near-Pareto-optimal solutions contains a number of non-dominated solutions, which the user can judge relatively and pick up the most promising one according to the problem requirements. Performance of the proposed algorithm has been demonstrated on two different network topologies with random traffic requests.

Electro-optic material has a great advantage for optical modulation. Phase modulation  has been successfully implemented  with the help of linear electro-optic Pockels materials. One can incorporate the idea of phase modulation to develop Phase Shift Keying (PSK) signal. A series of linear electro-optic Pockels materials with a fixed biasing voltage has been utilized to construct a theoretical model of PSK. PSK with light introduces the OFF state as zero phase change and the ON state as the π phase change of an incident carrier light wave. In  this proposed scheme, a series of Pockels cells  are used with a common biasing voltage. The voltage is given in such a way that the light after travelling through the series of Pockels cells gets a phase change ‘π’ for that voltage. This voltage is considered as Boolean ‘1’ and when there is no voltage applied (Boolean ‘0’) no phase change is expected.