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A dark-bright soliton conversion is used to perform the two arithmetic logic unit operations namely adder and subtractor operations. The advantage of the system such as power stability, non-dispersion and the dark-bright soliton phase conversion control can be obtained. The input source into the circuit is the bright soliton pulse, with the pulse width of 35 ps, the peak power at 1.55 µm is 1 mW. By using the dark-bright soliton conversion pair, the generated logic bits can be controlled, and the secure bits can be achieved. The simulation results show the output signal with a minimum loss of only 0.1% with respect to a low input power of 1 mW, and ultra-fast response time of about 1 ps can be achieved. It gives the ultra-high bandwidth of more than 40 Gbits−1. The circuit composes six microring resonators made of InGaAsP/InP material with smaller ring radii of 1.5 µm, and the total physical scale of the circuit less than 100 µm2. [ABSTRACT FROM AUTHOR]

Multi-input multi-output (MIMO) signals have been all-optically generated via orthogonal frequency division multiplexing, and transmitted over a 50 km single mode fibre (SMF) optical link and also a 5 m 2 × 2 MIMO wireless link. The series of constituent single and multi-carrier optical soliton pulses, at frequencies of f = 192.6988, f = 192.7588, f = 192.79 and f = 192.84 THz that are applicable for radio over fibre (RoF) systems, were created using a microring resonator system. Sixty four multi-carriers with specific free spectral range of 109.37 MHz across a selected range of 192.7553-192.7623 THz were produced for the purpose of establishing two MIMO V-Band RF signals, and single carriers operating at f and f optically transported two separate MIMO signals over an RoF link. The optical single sideband with carrier modulation technique has been implemented so as to overcome RF power degradation. The resultant bit error rate (BER) calculation of overall system performance is discussed, and power penalties of 1.7 and 4.7 dB in 25 and 50 km SMF transmissions at the BER threshold respectively have been identified. The results of this research show that transmission of MIMO signals is feasible for up to a 50 km SMF path length and wireless distance of 3 m. [ABSTRACT FROM AUTHOR]

The add-drop ring resonator system is the fundamental building block of optical transmission and communication systems. An add-drop microring resonator (MRR) consisting of a $$120\,\upmu \hbox {m}$$ diameter loop of optical waveguide was used to filter the input spectrum of a mode-locked laser. The experimental setup is used to generate soliton mode-locked laser pulse, where we used the experimental data to model and simulate the propagation of the mode-locked soliton laser pulse within the MRR. The transmission characteristics of the through and drop ports output signals from this system are described in this paper. As results, multi-wavelength mode lock soliton with full width at half maximum and free spectral range (FSR) of 8 pm and 0.67 nm were generated respectively. The FSR of the input signals are enlarged significantly by the system, thus separating signal wavelengths by a resonator has been investigated. In the proposed scheme, FSR-spaced signals are leveraged as a means of obtaining higher bandwidth output signals while using an add-drop MRR. [ABSTRACT FROM AUTHOR]

This paper presents a multi-soliton generation system for terabit data transmission. In this system, multi-solitons are produced by a series of micro-ring resonators (MRRs) incorporated with an add/drop filter. The generated multi-solitons are equalized by wavelength selective switch, therefore achieving flat frequency combs that can be used as multi-wavelengths for data transmission. The output signals from the MRRs, which have a soliton pulse range of 191.2-195.7 THz, result in 345 comb multi-wavelengths with specific FSR of 12.5 GHz. After the comb spectrum is split into odd and even carriers, 16-QAM is used to modulate each carrier with sinc-shaped Nyquist pulses. At this point, the modulation of neighboring carriers generates spectrally overlapping channels, which emulate orthogonal frequency division multiplexing. By applying 345 carriers, 16-QAM modulation, polarization multiplexing, and exploiting sinc-shaped Nyquist pulses with symbol rates of 12.5 GBd, a total data rate of 34.5 Tbit/s is achievable. The error vector magnitude and bit error rate of the system are also discussed. [ABSTRACT FROM AUTHOR]

Multi-carrier generation is the main building block for generating WiMax signal. In order to use WiMax signal in radio over fiber applications the use of all optical generation of RF signals is required. To generate multi carriers optically, the system consisting of series of microring resonators (MRRs) incorporating with an add/drop filter system are used. Thus the high frequency (THz) solitons range of 193.29-193.35 THz at frequencies of 193.333, 193.3355 and 193.3388 THz with the free spectral range of 2.5 and 5.8 GHz could be performed using MRRs, providing required WiMax signal used in wired/wireless communication. The generated multi carriers are multiplexed with the single carrier soliton and transmitted through single mode fiber (SMF) after being beaten to photodiode, a WiMax signal is propagated wirelessly in transmitter antenna base station and is received by the second antenna located in the receiver. Here, based on the switching of channel 1 or channel 2, the 2.5 or 5.8 GHz RF WiMax can be generated. When the RF signal is up-converted at the receiver central office, the detected signal is analysed in order to evaluate the error vector magnitude (EVM) of each wireless channel. As results, both channels show a soft EVM variation for different path lengths, where the transmission of both channels is feasible for up to a 50 km SMF path length. [ABSTRACT FROM AUTHOR]

SUMMARY A system consisting of a series of microring resonators, incorporating an add/drop system, is presented in order to create ultra-short spatial and temporal single and multisoliton pulses, which can be used for indoor and outdoor optical communications. Chaotic noise can be generated by a bright soliton pulse propagating inside a nonlinear microring resonator system. The results obtained show that a single temporal and spatial soliton pulse, with full width at half maximums of 75 fs, 80 fs, 700 fs, 4.4 ps, and 0.30 nm, can be generated. The add/drop system can be used to generate a high number of ultra-short soliton pulses in the ranges of nanometer/second and picometer/second. The simulated multisolitons have full width at half maximums of 16 ps, 20 pm, 130 ps, and 35 pm and free spectrum ranges of 500 ps, 0.57 nm, 3.5 ns, and 1.4 nm, respectively. The multisolitons generated at the drop port can be used in indoor optical communications, where the ultra-short pulses with a variety of central wavelengths (from λ = 1550 to λ = 1560) from the through port can be multiplexed-demultiplexed along an optical fiber with a length of 50 km. The filtered signals can be obtained at the end of the transmission link used for optical outdoor communications. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

New system of optical soliton signal generation with a high frequency band is presented. Microring resonator can be used to generate soliton signals with high frequency of GHz. These signals can be transmitted via a wireless network system known as WiMAX, which is providing broadband wireless access up to 50 km. The soliton pulses are more stable with less loss during propagation which is good candidate compare to other current optical waves used in optical communication. In this study, soliton pulses with full width at half maximum of 3 MHz and FSR of 85 MHz could be generated using an add/drop filter system which is used to generate high frequency signals, required for wireless network systems. These pulses can be used as carrier signals in order to transmit information codes without significant changes, thus improving transmission quality and delivery of the right information. [ABSTRACT FROM AUTHOR]

A microring resonator (MRR) system incorporating an add/drop system is presented. The finesse of the proposed system can be determined using the full width at half maximum (FWHM) and free spectrum range (FSR) of the generated multiple soliton pulses. The central wavelength of the bright input soliton pulse has been selected as 800 nm, at which a ring system with better sensitivity shows high finesse that is suitable for applications to many optical communication systems such as optical transmitters and sensors. Simulation results show that FSR of 0.3 nm and 1.1 ns and FWHM of 10 pm and 36.6 ps could be obtained. Therefore, a system with finesse of 30 can be obtained; in such a system, the MRR system shows high performance. This system can be used in optical communication networks as a transmitter system for optical soliton pulses with finesse of 30, and theses pulses can be detected via an optical receiver. [ABSTRACT FROM AUTHOR]

This study investigates the non-linear behaviours of light known as bifurcation and chaos during the propagation of light inside a non-linear silicon microring resonator (SMRR). The aim of the research is to use the non-linear behaviour of light to control the bifurcation and chaos of SMRR, which are used in engineering, biological and security systems. Bifurcation and chaos control deals with the modification of bifurcation characteristics of a parameterised non-linear system by a designed control input. The parameters of the SMRR cause bifurcation to happen in smaller round-trips among the total round-trip of 20 000 or input power. Effective parameters such as the refractive indices of a silicon waveguide, coupling coefficients (κ) and the radius of the ring (R) can be selected properly to control the non-linear behaviour. Simulated results show that rising non-linear refractive indices, coupling coefficients and radii of the SMRR lead to descending input power and round-trips when bifurcation occurs. Therefore bifurcation behaviour can be seen at a lower input power of 44 W, where the non-linear refractive index is n2 = 3.2 x 10-20 m²/W. The smallest round-trips of 4770 and 5720 can be seen for the R = 40 μm and κ = 0.1, respectively. [ABSTRACT FROM AUTHOR]