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An edge-emitting semiconductor laser (SL) source with a wavelength of 1310 nm is used experimentally to follow a transmitted signal that is subject to selected modifications. SL maximum measured optical power was -11 dBm at a temperature of 24oC, which is configured as a chaotic influencer semiconductor laser (ISL) in a unit of an optical neural network. The weight of the sent signal, after division, is controlled by two uniform Fiber Bragg gratings (FBGs) with slightly different periods. In addition, the feedback strength is changed by two radio frequency attenuators. The passing signal via these two filters is detected and summed again before being directly modulated and re-injected to the ISL again via the bias current. The results confirm a variable chaotic FWHM and bandwidth as a function of applied parameters. Emission for selected strengths is controlled by radio frequency attenuators after the power division. For each opto-electronic feedback (OEFB) branch, a noticeable difference in Fourier space is noted in addition to time and phase spaces. Results indicate a large variation in the calculated number of spikes (4268 to 71330) and also in the calculated FWHM (0.80991-10.5928) MHz This indicates the possibility of deriving the SL in a different number of quantum states by introducing filtered chaotic dynamics. Generalizations for the effect of optical weights, achieved in this study, open the door to increasing the processing speed in the processing units of computers and self-learning terms in robots. [ABSTRACT FROM AUTHOR]

We theoretically study chaos synchronization of two diodes that emit light using quantum dots (QDLED) which are delay coupled via a closed and open –loop coupling system active relay. While the chaotic systems are synchronized, their dynamics is identical to a single QDLED with delayed optoelectronic feedback for an open –loop system active relay. There is total synchronization in the system depending on the coupling parameters., i.e., the extent of the QDLED’s chaos regime under external optoelectronic feedback is evaluated in terms of the chaos synchronization residue and lag diagram for the optimal coupling strength range is debated as well. Under apposite conditions, the headset QDLED can be satisfactorily harmonized with the transmitter QDLED due to the optoelectronic feedback effect. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive numerical investigation on the generation of a microwave frequency comb (MFC) using a semiconductor laser subjected to periodic-modulated optical injection. To enhance performance, optoelectronic feedback is incorporated through a dual-drive Mach–Zehnder modulator. The results show that the first optoelectronic feedback loop, with a delay time inversely proportional to the modulation frequency, can optimize MFC generation through a mode-locking effect and the second optoelectronic feedback loop with a multiple delay time of the first one can further enhance the performance of the MFC. The comb linewidth appears to decrease with the increase in the second-loop delay time in the power function. These results are consistent with experimental observations reported in the literature. We also explore the impact of the feedback index on comb contrast, the statistical characteristics of the central 128 lines within the MFC, and side peak suppression. The simulation results demonstrate the presence of an optimal feedback index. The study also reveals that linewidth reduction, through increasing the feedback index and delay time, comes at the cost of declining side peak suppression. These findings collectively contribute to a deeper understanding of the factors influencing MFC generation and pave the way for the design and optimization of high-performance MFC systems for various applications. [ABSTRACT FROM AUTHOR]

This study presents a comprehensive numerical investigation on the generation of a microwave frequency comb (MFC) using a semiconductor laser subjected to periodic-modulated optical injection. To enhance performance, optoelectronic feedback is incorporated through a dual-drive Mach–Zehnder modulator. The results show that the first optoelectronic feedback loop, with a delay time inversely proportional to the modulation frequency, can optimize MFC generation through a mode-locking effect and the second optoelectronic feedback loop with a multiple delay time of the first one can further enhance the performance of the MFC. The comb linewidth appears to decrease with the increase in the second-loop delay time in the power function. These results are consistent with experimental observations reported in the literature. We also explore the impact of the feedback index on comb contrast, the statistical characteristics of the central 128 lines within the MFC, and side peak suppression. The simulation results demonstrate the presence of an optimal feedback index. The study also reveals that linewidth reduction, through increasing the feedback index and delay time, comes at the cost of declining side peak suppression. These findings collectively contribute to a deeper understanding of the factors influencing MFC generation and pave the way for the design and optimization of high-performance MFC systems for various applications.

In this research, we demonstrated the Modeling and simulation of Mach-Zehnder modulator(MZM) with optoelectronic feedback(OEFB) to generate optical instabilities output (periodic, quasi-periodic and chaos spatial signal). The Integrodifferential equation is the basis of this model. Control of the instabilities region of optical output from MZM been done optoelectronic feedback OEF delay time. The results of the numerical solutions of the system of delay differential equations (DDE) for the OEO system showed that there is very large diversity in the oscillation systems, ranging from single oscillation, double-period oscillation, multi-period oscillations, and chaotic oscillations respectively, as functions of the photoelectric feedback delay times τD when the linear gain coefficient is fixed at the value of 3. The results of the numerical solutions also showed an increase in the dimensions of the chaotic oscillations at the large values of the delay times τD of the optoelectronic feedback. Numerical simulation results of the bifurcation diagram showed wide diversity of oscillation regimes, ranging fromsingle period, period two, mixed-mode, quasi-periodic and chaotic oscillations, which are all functions of delay time parameter TD . [ABSTRACT FROM AUTHOR]

Chaotic lasers are widely used in secure communication, optical detection and other applications due to their noise-like randomness, excellent anti-jamming and other advantages. This research looks into the chaotic laser's performance at a low cost. The performance related to a semiconductor laser with double delayed feedback is observed and its characteristics are determined in experimental research utilizing OptiSystem simulator. The chaotic laser output is fed back to the Mach-Zehnder modulator (MZM) to make the original system. The gain coefficient changes dynamically, and a second time delay is introduced into the system. The feedback time and feedback strength of the improved chaotic system are studied under varying input bias current, frequency and modulation beak current. Bifurcation diagram results show that the chaotic laser output by the optoelectronic oscillator (OEO) is more complex and has lower delay characteristics. This method does not increase too much Under the premise of system cost, more complex chaotic signals can be generated, and the signal delay characteristics can be reduced, which is conducive to improving the security of the communication system. [ABSTRACT FROM AUTHOR]

We propose a scheme for key-space-enhanced chaos secure communication using semiconductor lasers with spectrum-programmable optoelectronic feedback. This feedback consists of multiple parallel optoelectronic feedback loops composed of bandpass filters and radio-frequency amplifiers. The centre frequencies of the filters and gain coefficients of the amplifiers increase the key space. We use 12 parallel filtered feedback loops to analyse the effects of parameter mismatch on the synchronization quality. The simulation result indicates that the key space reaches approximately 2100 at a data rate of 10 Gbit/s, and it can be further enhanced by increasing the number of feedback loops. These results suggest an alternative approach for security-enhanced optical chaos communication. [ABSTRACT FROM AUTHOR]

We proposed a new reservoir computation (RC) structure using polarization dynamics of vertical cavity surface emitting lasers (VCSELs) with optoelectronic feedback. Santa-Fe time-series prediction and nonlinear channel equalization were used to evaluate its parallel processing capability. We numerically discussed the effects of feedback strength, injection strength, frequency detuning, injection current and scaling factors on the RC performance of the system. The results show that, the operation range of negative feedback is larger than that of positive feedback; under appropriate feedback and lager injection strengths, good RC performance can be achieved for a wider injection current; with continuous variation of feedback strength from negative to positive values, the optimized location for frequency detuning moves from positive to negative values. We also evaluated the processing rate of proposed RC structure. The related study is helpful for the design and optimization of VCSEL-based RC under optoelectronic feedback. [ABSTRACT FROM AUTHOR]

We propose a scheme for key-space-enhanced chaos secure communication using semiconductor lasers with spectrum-programmable optoelectronic feedback. This feedback consists of multiple parallel optoelectronic feedback loops composed of bandpass filters and radio-frequency amplifiers. The centre frequencies of the filters and gain coefficients of the amplifiers increase the key space. We use 12 parallel filtered feedback loops to analyse the effects of parameter mismatch on the synchronization quality. The simulation result indicates that the key space reaches approximately 2100 at a data rate of 10 Gbit/s, and it can be further enhanced by increasing the number of feedback loops. These results suggest an alternative approach for security-enhanced optical chaos communication.

Optoelectronic feedback on a laser diode is demonstrated to generate two distinct modes of periodic pulse-train formation depending on the injection current J of the laser leading to microwave combs in two distinct regimes. For J close to the threshold current Jth, the pulse repetition rate ƒrep is the inverse of the loop delay. This behavior is attributed to feedback-induced gain-switching and leads to comb spacings in the tens of MHz range. In contrast, for J ≅ 2Jth, the repetition rate ƒrep is observed to be related to the relaxation-oscillation frequency ƒRO. The potential to generate pulse trains and associated microwave combs may find use in metrology, optical communications, optical sampling, and spectroscopy. [ABSTRACT FROM AUTHOR]

An acousto-optic system containing collinear acousto-optic filter fabricated from calcium molybdate crystal and a positive electronic feedback was examined. The feedback signal is formed due to the optical heterodyning effect that appears for the special geometry of polarizer and analyzer polarization planes mutual orientation between which the collinear filter is located. It is shown that the feedback circuit electrical parameters variation enable controlling the spectral characteristics of the acousto-optic collinear filtration, resulting in enhancing the maximal spectral resolution and transmission function side lobes suppression.

In this paper, the distortion of the transistor laser (TL) has been analysed. The typical diode laser and transistor lasers support not only for current controlled modulation but also in the voltage-controlled modulation. We investigate the small signal voltage modulation features of transistor lasers (TL) using FK absorption related to optoelectronic feedback and rate equations for diode lasers, and this model physically includes the various FK absorption effects. Due to Franz Keldysh (FK) absorption, an optically induced current drastically alter the voltage response in transistor lasers. The voltage modulation characteristics in transistor lasers have proposed an optical response method and an electrical function for which this optical response is fed back. [ABSTRACT FROM AUTHOR]

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In this paper, an experimental and numerical study for the evolution of the non-linear dynamics of semiconductor laser has been done under two conditions, when the dc bias current of Semiconductor laser is varied, and when the feedback strength is varied. These dynamics were analyzed by time series and their extracted(FFT) power spectrums, phase diagrams (attractors),inter-spike intervals(ISI), these measurements enhanced by bifurcation diagram which explained the chaotic regimes. The stability states using different control parameters have been demonstrated. The role of control parameters of laser such as: dc bias current and feedback strength is proved in spiking generation and chaos control in the laser output.

In this paper, a multiple-input multiple-output reservoir computing (RC) system is proposed, which is composed of multiple nonlinear nodes (Mach−Zehnder modulators) and multiple mutual-coupling loops of optoelectronic delay lines. Each input signal is added into every mutual-coupling loop to implement the simultaneous recognition of multiple route signals, which results in the signal processing speed improving and the number of routes increasing. As an example, the four-route input and four-route output RC is simultaneously realized by numerical simulations. The results show that this type of RC system can successfully recognize the four-route optical packet headers with 3-bit, 8-bit, 16-bit, and 32-bit, and four-route independent digital speeches. When the white noise is added to the signals such that the signal-to-noise ratio (SNR) of the optical packet headers and the digital speeches are 35 dB and 20 dB respectively, the normalized root mean square errors (NRMSEs) of the signal recognition are all close to 0.1. The word error rates (WERs) of the optical packet header recognition are 0%. The WER of the digital speech recognition is 1.6%. The eight-route input and eight-route output RC is also numerically simulated. The recognition of the eight-route 3-bit optical packet headers is implemented. The parallel processing of multiple-route signals and the high recognition accuracy are implemented by this proposed system.

We analyze the dynamics of a class B laser with optoelectronic delayed feedback and periodic modulation of the delay time. For the delay-differential model, we describe asymptotically spike regimes with various properties, namely, with inter-spikes intervals greater than delay, less delay, and a mixed type. Sets of initial conditions in an infinite-dimensional phase space are determined for each type of pulsed solutions. The dynamics of each regime is described by the dynamics of a certain finite-dimensional mapping. By computing the maps we obtain the modulation parameters at which the chaotic spiking of desired structure is realized. We demonstrate bistability of chaotic spiking, their intermittence and merge. [ABSTRACT FROM AUTHOR]

An optoelectronic feedback reservoir computing (RC) system that can identify optical packet headers for an optical packet switching (OPS) network is proposed and implemented by the numerical simulation and the experiment in this paper. First, a simulation system of optical packet header recognition based on the optoelectronic feedback RC is established through optimizing its parameters. It is shown that the optoelectronic feedback RC system can correctly identify optical packet headers with lengths from 3 bits to 32 bits and that the recognition word-error rate (WER) is 0. Then, an experiment system consistent with the optimal simulation system is set up, whose WER for the 3-bit header recognition is only 1.25%. The experimental results also indicate that the bias voltage of the Mach–Zehnder modulator (MZM) has a significant impact on recognition results. When the RC system is in the critical state between the multiple-period oscillation and the chaos, the maximal Lyapunov exponent is slightly larger than 0, and the recognition normalized root-mean-square error (NRMSE) reaches its minimal value. [ABSTRACT FROM PUBLISHER]

We report results on the asymptotic, bifurcation and numerical analysis of semiconductor ring lasers with negative optoelectronic feedback or incoherent optical feedback. We find that the dynamical behavior of both systems can be adequately described by two differential equations and one map with time delay on time-scales longer than the relaxation oscillations. On these timescales, the dynamics for both types of feedback is identical. We study the stationary solutions of this model and are able to obtain the analytical expressions of all local bifurcations. As we vary the feedback strength for small delay times comparable to the period of relaxation oscillations, the devices under consideration in the paper display both continuous wave operation and a period-doubling route to chaos. The intensities of two counter propagating modes of both systems exhibit in-phase chaotic behavior similar to single mode semiconductor lasers. However, for long delay times, the counter propagating modes show anti-phase chaotic oscillations. This anti-phase chaotic regime does not involve carrier dynamics and is a result of the bistable character of the semiconductor ring laser. [ABSTRACT FROM AUTHOR]

Abstract: Secure chaos based multiplex communication system scheme is proposed utilizing globally coupled semiconductor lasers with multiple variable time delay optoelectronic feedbacks. [Copyright &y& Elsevier]

Abstract: Based on the framework of the spin-flip model (SFM), the polarization dynamics of vertical-cavity surface-emitting lasers (VCSELs) subjected to optoelectronic feedback has been investigated numerically. The results show that nonlinear dynamics are similar to what have been observed in VCSELs with negative optoelectronic feedback, such as polarization switching (PS), antiphase and inphase fluctuations, mode competition and quasi-period routes to chaos. The difference between them is that VCSELs subjected to optoelectronic feedback emit only in the yLP mode if the feedback strength is large enough. Moreover, the synchronization performance of unidirectionally coupled VCSELs subjected to optoelectronic feedback has also been investigated. The polarized mode in the single mode region (region A) can achieve complete synchronization. Within the mixed-mode region (region B), the synchronization quality of polarized modes is not ideal. [Copyright &y& Elsevier]

Abstract: The optoelectronic feedback (OEF) in quantum dot semiconductor lasers (QD SLs) is studied theoretically where a model includes wetting layer ground state and excited state for QDs are included separating electrons and holes in their dynamics. Both positive and negative OEF are studied. The time series of photon density, the phase portraits of carriers in the states are studied. The parameters affecting OEF are examined where an excitability is seen. The QD SL is found to be more sensitive to the changes in time delay compared with other SLs and a complicated routs are seen in the behavior of QD SL. [Copyright &y& Elsevier]

This paper addresses the need for self-consistent simulation of mixed electrical and optical circuits and systems. Drawing on the use of modified nodal analysis (MNA) techniques ubiquitous in circuit simulation, an optical node is formulated which includes the magnitude and phase of the optical signal being simulated. This node consists of two propagating complex envelopes one for the forward direction and the other for the reverse direction. Using this formulation models are developed for a variety of devices including: lasers, photodiodes, multimode fiber, and optical connectors. The formulation allows for definition of multiple optical channels at different carrier frequencies, enables quick simulation of systems with large optical delays and optical interference effects. Several numerical examples are presented in this paper to illustrate the capability of the proposed framework and where practicable the results were compared to commercial simulators. These examples include a multimode fiber optical link, an integrated array of laser sources and a feedback controlled laser source used in a optical link with modulation achieved by the use of an electro-absorption device. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, a bidirectional chaos communication system based on the optoelectronic feedback semiconductor lasers (SLs) is presented, and the synchronization characteristics and the communication performances of such system are simulated numerically. The results show that the high-quality synchronization with zero lag time and simultaneous bidirectional message transmission can be realized under the suitable system parameters; the internal parameter mismatches of the lasers have influence on the synchronization quality and communication performance, but this system still possesses good robustness to parameter mismatches. Meanwhile, the security can be ensured through a suitable encoding–decoding technique. [Copyright &y& Elsevier]

Abstract: A directly modulated CATV/radio-on-fiber (ROF) transport system based on light injection and optoelectronic feedback techniques, and photonic crystal fiber (PCF) is proposed and demonstrated. Excellent performances of carrier-to-noise ratio (CNR), composite second order (CSO) and composite triple beat (CTB) were obtained for CATV band; as well as low bit error rate (BER) and third order intermodulation distortion to carrier ratio (IMD3/C) values were achieved for ROF band. This demonstrated that such a CATV/ROF transport system is very attractive for the fiber backbone applications. [Copyright &y& Elsevier]

Abstract: An optoelectronic noise suppression circuit connected to the RF input of a commercial diode laser mount is presented. Adjustable phase shift and amplitude control enable efficient suppression of the relaxation oscillations of a diode laser-pumped Nd: laser at variable frequencies between a few hundred kHz and 1.8MHz. At least 25dB reduction of the relaxation oscillations at 500kHz and 1.5MHz noise peaks is demonstrated. [Copyright &y& Elsevier]

Abstract: A radio-on-multimode fiber (MMF) system based on vertical-cavity surface-emitting lasers (VCSELs) injection-locked and optoelectronic feedback techniques is proposed and demonstrated. Injection locking and optoelectronic feedback achieves large frequency response of the VCSEL, resulting in good performances of intermodulation distortion to carrier ratio (IMD/C), error vector magnitude (EVM), and bit error rate (BER). Using VCSELs as optical sources in radio-on-MMF systems are very attractive, as they are relatively simple to fabricate and potentially low-cost. Such a proposed radio-on-MMF system is suitable for the short-haul microwave optical links. [Copyright &y& Elsevier]

Abstract: General operation conditions to obtain anticipated or retarded synchronization in a mutually coupled system with feedback are analyzed. Different from a unidirectionally coupled system, which type of synchronization will occur in a mutually coupled system does not solely depend on the difference between the feedback-delay time and the coupling-delay time. We find that in addition to the feedback/coupling delay times, feedback strengths and coupling strengths all determine whether the system will preform anticipated or retarded synchronization. Experimental implementation using semiconductor lasers subject to optoelectronic feedback is provided as an example. A set of experimental data is presented and discussed. [Copyright &y& Elsevier]

Generation of a broadly tunable narrow-linewidth microwave subcarrier on an optical wave by exploiting the nonlinear dynamics of a semiconductor laser through a proper combination of optical injection and optoelectronic feedback is experimentally demonstrated. The microwave frequency is generated by the period-one oscillation of an optically injected semiconductor laser. It is tuned in the range from 10 to 23 GHz by varying the optical injection strength, and its linewidth can be narrowed by optoelectronic feedback alone. The linewidth is reduced from the range of 40-120 MHz without stabilization by three orders of magnitude to the range of 10-160 kHz with stabilization through optoelectronic feedback alone. The effect of a small microwave modulation is also investigated. It reduces the linewidth to below the 1-kHz resolution limit of our instrument. [ABSTRACT FROM PUBLISHER]

Mutually coupled oscillators are currently of great interest because of the important insight they provide into coupled physical, chemical, and biological systems. Two semiconductor lasers with optoelectronic feedback are used as two nonlinear oscillators, and the effect of mutual coupling on these lasers is found to be significant. Depending on the operating conditions, mutual coupling can act as a negative feedback to stabilize the coupled oscillators, or it can increase the complexity of the system inducing a highly complex chaos. A quasi-periodicity and period-doubling bifurcation, or a mix of them, is found in such a system. Although the chaotic waveforms are very complex with broad spectra, a high quality of synchronization between the chaotic waveforms is observed. Such synchronization is achieved because of the effect of mutual coupling and the symmetric design between the two lasers. It is found that the time delay of coupling plays an important role on the dynamics and synchronization in the mutually coupled semiconductor lasers. [ABSTRACT FROM PUBLISHER]

Generalized synchronization is characterized by the existence of a functional relationship between the dynamical evolution of a response system driven by an external signal. We observe generalized synchronization of chaos in a neodymium-doped yttrium aluminum garnet (Nd:YAG) microchip laser with optoelectronic feedback. The electronic feedback signal driving the chaotic dynamics of a laser is recorded in a computer. Feedback is removed and the recorded signal is replayed to the laser. Instead of repeating the original dynamics, the laser displays generalized synchronization to the recorded waveform. We observe similar results in numerical simulations using a two-mode laser model. The feedback signal is the total intensity, while the microchip laser dynamics is governed by the mode–mode interaction through spatial hole burning of the population inversion, the description of which requires several additional degrees of freedom. Generalized synchronization can arise from the existence of hidden degrees of freedom in the laser dynamics that are lumped together in the feedback signal. [Copyright &y& Elsevier]

Nonlinear dynamical characteristics of an optically injected semiconductor laser subject to optoelectronic feedback is studied numerically. The dynamic states including stable locking, periodic oscillation, chaotic oscillation, regular pulsing, quasiperiodic pulsing, and chaotic pulsing seen in a semiconductor laser subject to either optical injection or delayed optoelectronic feedback alone, can all be found in this hybrid system where the laser is subject to both optical injection and optoelectronic feedback. While this system can follow either the period-doubling or the quasiperiodic route to chaos, transition states bridging chaotic oscillation states and chaotic pulsing states are identified and shown. Mappings of dynamic states in the parameter space are plotted, where a large expansion and shifting of the chaos region is observed and is compared with an optically injected laser without optoelectronic feedback. As the injection strength increases, the bandwidths of the chaotic states in the broadened area of this hybrid system are significantly enhanced. The advantages and potential applications of this hybrid system are discussed. [Copyright &y& Elsevier]

The application of optoelectronic feedback in addressing various problems in smart pixel arrays is considered. Special attention is paid to issues associated with light sources such as device nonlinearity and nonuniformity. Moreover, new classes of smart pixel applications taking advantage of the useful properties of optoelectronic feedback are discussed. Experimental results from a demonstration chip based on monolithic integration of optoelectronic devices on GaAs substrate are presented [ABSTRACT FROM PUBLISHER]

Abstract: An optoelectronic feedback loop intended to suppress intensity noise of a light field is introduced in this paper. A maximum intensity noise reduction of 10dB is experimentally achieved between frequency of 0⿿140kHz on a 1064nm DPSS continuous wave single-frequency solid-state laser. After optimization and miniaturization, this system is expected to be widely used as a simple ⿿Noise-Eater⿿. [Copyright &y& Elsevier]

A bidirectional radio-over-dense-wavelength-division-multiplexing transport system using injection-locked and optoelectronic feedback controlled vertical-cavity surface-emitting lasers (VCSELs) is proposed and demonstrated. It is shown that the system performance, which is evaluated by using bit-error rate, error vector magnitude, and intermodulation distortion-to-carrier ratio, is improved due to using injection-locked and feedback controlled VCSELs [ABSTRACT FROM PUBLISHER]

A split-band directly modulated fiber-optical cable television system employing light injection and optoelectronic feedback techniques is proposed and demonstrated. The light injection technique enhances the laser resonance frequency, and the optoelectronic feedback technique further enhances it, leading to an improvement in the systems' overall performances. Good performances of carrier-to-noise ratio, composite second order, and composite triple beat were achieved for the full channel band over a 100-km single-mode fiber transport [ABSTRACT FROM PUBLISHER]

In this paper, a multiple-input multiple-output reservoir computing (RC) system is proposed, which is composed of multiple nonlinear nodes (Mach–Zehnder modulators) and multiple mutual-coupling loops of optoelectronic delay lines. Each input signal is added into every mutual-coupling loop to implement the simultaneous recognition of multiple route signals, which results in the signal processing speed improving and the number of routes increasing. As an example, the four-route input and four-route output RC is simultaneously realized by numerical simulations. The results show that this type of RC system can successfully recognize the four-route optical packet headers with 3-bit, 8-bit, 16-bit, and 32-bit, and four-route independent digital speeches. When the white noise is added to the signals such that the signal-to-noise ratio (SNR) of the optical packet headers and the digital speeches are 35 dB and 20 dB respectively, the normalized root mean square errors (NRMSEs) of the signal recognition are all close to 0.1. The word error rates (WERs) of the optical packet header recognition are 0%. The WER of the digital speech recognition is 1.6%. The eight-route input and eight-route output RC is also numerically simulated. The recognition of the eight-route 3-bit optical packet headers is implemented. The parallel processing of multiple-route signals and the high recognition accuracy are implemented by this proposed system. [ABSTRACT FROM AUTHOR]

A bidirectional wavelength-division-multiplexing (WDM) transport system base on two reflective semiconductor optical amplifiers (RSOAs) and optoelectronic feedback technique is proposed and experimentally demonstrated. One RSOA is employed as a broadband light source and another RSOA in combination with optoelectronic feedback technique is used as wavelengths reuse and data signal remodulation scheme. System architecture is further simplified by using only one RSOA at the optical node, and system performance is further improved by optoelectronic feedback technique. Impressive performances of bit error rate (BER) (<10^-9) were achieved for both 2.5 Gbps down-link and 1.25 Gbps up-link transmissions. [ABSTRACT FROM PUBLISHER]