A multi-objective genetic algorithm approach is formulated to optimize the design of silicon-photonics complex circuits with contradicting performance metrics and no closed-form expression for the circuit performance. A case study is the interleaver/deinterleaver circuit which mixes/separates optical signals into/from different physical channels while preserving the wavelength-division-multiplexing specifications. These specifications are given as channel spacing of 50 GHz, channel 3-dB bandwidth of at least 20 GHz, channel free spectral range of 100 GHz, crosstalk of −23 dB or less, and signal dispersion less than 30 ps/nm. The essence of the proposed approach lies in the formulation of the fitness functions and the selection criteria to optimize the values of the three coupling coefficients, which govern the circuit performance, in order to accommodate the contradicting performance metrics of the circuit. The proposed approach achieves the optimal design in an incomparably short period of time when contrasted with the previous tedious design method based on employing Z-transform and visual inspection of the transmission poles and zeros.

Introducing high speed networks, such as the fifth generation of mobile technology and related applications including the internet of things, creates a pressing demand for hardware infrastructure that provides sufficient bandwidth. Here, silicon-based microwave-photonics presents a solution that features easy and inexpensive fabrication through a mature platform that has long served the electronics industry. In this work, the design of an electro-optic modulator is proposed where the ‘fin’ structure is adopted from the domain of electronics devices, with emphasis on the high speed of operation. The proposed modulator is customized to provide a bandwidth of 90 GHz with a small phase shifter length of 800 μm and an optical insertion loss of 4 dB. With such a speed, this proposed modulator fits high-speed applications such as modern tele-communications systems.

Throughout a careful step-by-step study, two simple designs of electro-optic modulators are proposed. The study shows the effect of dimensions and doping concentration on the performance parameters such as the modulation bandwidth, the size, the insertion loss and the extinction ratio. One design shows a modulation bandwidth of 54.5 GHz with a relatively short phase shifter length of 2.5 mm , a low optical insertion loss of 1.1 dB and a very high extinction ratio of 30 dB . The other one shows a bandwidth of 12.8 GHz , a phase shifter length of 9 mm , an optical insertion loss of 3.3 dB and an extinction ratio of 3 dB . It is shown that these two designs can fit to the requirements of the 5G telecommunications networks at different points which require different speeds of operation. The designs feature the complementary-metal-oxide-semiconductor technology advantages of ease and low-cost of fabrication.

The following topics are dealt with: learning (artificial intelligence); image classification; feature extraction; social networking (online); medical image processing; support vector machines; data mining; pattern classification; Internet of Things; parallel processing.