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Topology aggregation is very important for multi-domain network. To deal with wavelength and timeslots constrains in multi-domain WDM-TDM networks, a topology aggregation scheme is proposed in this paper. The proposed scheme is based on asymmetric star with bypasses structure and comprehensively considers the information of multi-path between each border nodes pair. Results show that our proposed scheme obtains a better tradeoff between information accuracy and information reduction.

All-optical WDM networks are the most promising candidate for the next generation wideband backbone networks. To improve the utilization of wavelength, TDM technology is introduced into it. The routing, wavelength and time-slots assignment (RWTA) problem was studied in such time-space switched networks. A new adaptive algorithm was proposed which adopt adaptive network link weights and distribute slots of the session request on multiple different wavelengths adaptively with the remainder resource of the network. The effectiveness of the proposed algorithm is demonstrated by simulations and results show the better performance.

Due to the lower channel utilization in conventional wavelength-routed networks, TDM technique is implemented on top of WDM to achieve a WDM-TDM network. RWTA problem in WDM-TDM networks is discussed. With the idea that assigned time-slots of one session can be distributed in multiple different wavelengths and the objective of minimizing network blocking probability, a RWTA algorithm called MUMD was proposed for dynamic traffic in mesh single-fiber networks. Then we demonstrate the performance of the proposed MUMD algorithm through numerical simulation. The results show that MUMD can efficiently optimize the network blocking performance, thereby optimize the resource utilization.

A novel triplexer chip based on an asymmetric Y branch waveguide and a multimode interference is presented in this paper. Using the novel triplexer chip, a 1310nm channel is multiplexed and 1490nm and 1550nm channels are demultiplexed for FTTH using. The asymmetric Y branch waveguide is used to separate the 1310nm channel from the 1490nm and 1550nm channels. Then the multimode interference is used to demultiplex the 1490nm from 1550nm channel. The simulated spectra show the bandwidths of three response wavelengths are 100nm, 20nm and 10nm, respectively, which can meet the demand of ITU.984 completely. The isolation for 1310nm is more than 48dB, and the isolation between 1490nm and 1550nm is more than 37dB.

To improve the density of information storage, this paper introduces a kind of annular binary filters with super-resolution, Several of these filters have been designed based on the genetic algorithm, the simulations demonstrate that the transverse gain of the filters can reach the value of 1.37. Thus they can remarkably decrease the recording spot size, which is helpful to improve the density of, information storage and to make the depth of focus, longer, and therefore they can avoid the mistake caused by the small undulation of the optical disk in the process of recording/reading the information.

The thermal and chemical stabilities of Mo/Si multilayer structure used in Bragg-Fresnel optics were studied to get optimal technological parameters of pattern generation. Mo/Si multilayers were annealed at temperature ranging from 360 to 770 K, treated with acetone and 5 parts per thousand NaOH solution, and characterized by small-angle x-ray diffraction technique as well as x-ray photoelectron spectroscopy, and Olympus microscopy.