A fiber Bragg grating (FBG) is one of the most common and widely used fiber optic sensors. One main issue when using a FBG-based sensor is that it is simultaneously sensitive to both the strain and the temperature, and compensation for the temperature and strain effects is necessary to measure these parameters. The available compensation techniques mean that the interrogation of FBG sensor systems is complex and make sensor networks bulky by increasing the number of sensors. Several of these compensation techniques are not feasible in in situ applications. In this paper, we propose a method for discriminating between the strain and the temperature by measuring the change in the single Bragg wavelength. Our proposed technique is based on measuring the sidelobe power, which appears adjacent to the main Bragg peak due to the strength of the interference between the forward and backward propagating waves of the Bragg grating sensor. We demonstrate by experiments that the proposed methodology can discriminate between the strain and temperature effects, making the interrogation system less complex with a very reasonable hardware cost.

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The elastic optical network (EON) is the latest solution to increase the capacity of optical networks, as a response to the ever‐increasing demand for traffic. To meet the EON mission, new algorithms and frameworks need to be designed. In this paper, a new algorithm based on EON is proposed that employs a subtree‐based scheme to establish multicast transmissions. To solve the problems of routing, modulation level and spectrum allocation, the primary problem of EON with regard to resource allocation under wavelength continuity and wavelength contiguity constraints, as well as distance adaptive transmission, the proposed algorithm solves each subproblem by considering the existence of a solution for other subproblems. The authors take into account the effects of splitting the transient light at the intermediary nodes on the signal‐to‐noise ratio to enhance the accuracy of the resource allocation. The proposed scheme is extensively examined under different networks and compared with the existing multicasting benchmark. The simulation results show that the proposed scheme considerably increases the network capacity without placing any burden on the network.

Routing, modulation and spectrum allocation in elastic optical networks is a problem aiming at increasing the capacity of the network. Many algorithms such as shortest path algorithm can be used as the routing section of this problem. The efficiency of these algorithms is partly based on how the cost on each link is defined. In this study, we consider several basic costs and compare their effects on the network capacity. In particular, the static costs and the dynamic costs are evaluated and compared; For dynamic scenarios, compared to static scenarios, at least one additional factor is added that, for instance, can be usage of the link. We further consider a new factor that is based on probability of accommodating the signal at a given time in any given link. The results show that, among them, the shortest path algorithm provides the least blocking probability when the cost is a combination of link length and the abovementioned possibility/ usage of the link.