We propose and numerically demonstrate a scheme of coherent optical chaos communication using semiconductor lasers for secure transmission quadrature amplitude modulation (QAM) signals. In this scheme, laser intensity its delayed duplicate are used to amplitude-quadrature modulate continuous-wave light generate chaotic carrier. High-quality carrier synchronization between the transmitter receiver is guaranteed by synchronization, avoiding phase fluctuation. Decryption implemented 90 deg...

Noninvasive and sensitive thermometry is crucial to human health monitoring applications in disease diagnosis. Despite recent advances optical temperature detection, the construction of wearable sensors remains a considerable challenge. Here, flexible biocompatible sensor developed by combining plasmonic semiconductor W18O49 enhanced upconversion emission (UCNPs/WO) with poly(lactic acid) (PLA)-based fibers. The UCNPs/WO offers highly thermal-sensitive obviously dual-wavelength emissions for...

Providing physical layer security at the lowest network in fiber-optic communication systems is a technical challenge worldwide. Here, we propose and experimentally demonstrate pure hardware optical encryption scheme based on temporal spreading self-feedback phase for high-speed long-distance physical-layer secure communication. A record high bit-rate-distance product of 6400 Gb/s km successfully achieved by transmission 32 on-off-keying modulated confidential signal over 200 fiber link. The...

The performance of high-speed intensity modulation direct detection (IM-DD) transmissions is severely degraded by the linear inter-symbol interference (ISI), due to both bandwidth-constrained optoelectrical components and chromatic dispersion (CD). Meanwhile, nonlinear ISI square-law can further deteriorate IM-DD system significantly. Here, we first propose three metrics quantify those impairments in transmissions. Then, compare BER computational complexity different DSP schemes enable...

In the current context of information explosion, securing physical layer in backbone networks coherent optical communication is vitally important. this letter, we experimentally validate a secure scheme for systems based on electro-optic phase feedback encryption, thereby successfully transmitting 40 Gb/s dual-polarization quadrature shift keying (DP-QPSK) signal over distance 180 km. By strategically incorporating delay line interferometer and dispersion component within loop, it possible...

In this paper, we analyze waveform generation using a single-stage dual-drive Mach-Zehnder modulator and dispersive fiber. We derive mathematical expression for the process in time domain use to propose algorithm. Furthermore, versatile waveforms, such as short pulse, trapezoidal, triangular sawtooth waveforms doublet are theoretically generated under different combinations of four variables. The analyzed terms gradient instantaneous frequency. Finally, is experimentally demonstrated at...

We present a photonic approach for fast quantum random number generation based on optically sampled amplified spontaneous emission (ASE). This utilizes terahertz optical asymmetric demultiplexer to sample the ASE and then digitize pulses into bits using multi-bit parallel comparator. A proof-of-concept experiment demonstrates that 40 Gb/s with verified randomness can be obtained our method. The current rate is mainly limited by bandwidth of available source.

Protecting confidential high speed optical signal transmission at the lowest physical layer is a critical challenge for modern fiber-optic communication systems. In this paper, we experimentally demonstrate novel synchronous privacy enhanced chaotic temporal phase en/decryption scheme high-speed secure communication. A remote chaos synchronization architecture relying on common source driving and private response hardware modules comprising of dispersive components slave lasers employed to...

Chaotic optical communication has recently garnered considerable research interest for providing physical layer security. In this work, we propose and demonstrate a secure space-division-multiplexing (SDM) system based on multi-channel chaos random en/decryption with remotely synchronized Fabry-Perot (FP) lasers. By combination of multi-longitudinal modes from the FP lasers, low-correlated chaotic signals can be produced then utilized encrypting confidential data, which effectively provides...

High speed physical secure key distribution in a classical optical fiber channel is unprecedentedly desired for modern communication, but it still remains worldwide technical challenge. In this paper, we propose and experimentally demonstrate novel high-speed scheme based on chaotic signal processing private hardware modules, which employs self-carrier phase modulation bandwidth expansion time-delayed shift keying of commonly driven synchronized chaos layer security. scheme, the entropy...

Security enhancement of stealth channel by combining time-domain spectral phase en/decoding (SPE/D) OCDMA scheme and group velocity dispersion is proposed experimentally demonstrated. The encoded signal, which utilizes a linearly chirped fiber Bragg grating for pulse broadening high-speed modulator SPE, has been transmitted over public wavelengthdivision-multiplexing network. Error-free transmission (bit-error rate <; 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...

We propose and experimentally demonstrate a time-domain bit-by-bit code-shifting scheme that can rapidly program ultralong, code-length variable optical code by using only dispersive element high-speed phase modulator for improving information security. The proposed operates in the bit overlap regime could eliminate vulnerability of extracting analyzing fine structure spectral encoded signal. It is also intrinsically immune to eavesdropping via conventional power detection...

In this paper, a novel phase encryption scheme based on dual-loop electro-optic self-feedback structure is proposed for time-delay signature (TDS) concealment. As conventional single-loop feedback structure, the TDS extremely vulnerable to exposure in common link, resulting fatal weakness entire security system, whereas, introduction of an additional branch, brings about mutual dynamics between feedbacks, and effectively solves problem. The modulation depth dispersion values, which are two...

The security and confidentiality of information are crucial in contemporary communication systems. In this work, we propose a physical layer security-enhanced optical scheme based on dual-level protection with chaos masking (CMS) chaotic hardware encryption. integration CMS encryption contributes to enhancing the system. Different uncorrelated generated from single Fabry-Perot (FP) laser employed independently mask encrypt confidential signals for multiple channels wavelength division...

A novel scheme using single phase modulator for simultaneous time domain spectral encoding (SPE) signal generation and DPSK data modulation is proposed experimentally demonstrated. Array- Waveguide-Grating Variable-Bandwidth-Spectrum-Shaper based devices can be used decoding the directly in domain. The effects of fiber dispersion, light pulse width timing error on coding performance have been investigated by simulation verified experiment. In experiment, SPE with 8-chip, 20GHz/chip optical...

In this reported work, differential detection to eavesdrop the encoded information in temporal phase coding code-shift-keying OCDMA system, is proposed and experimentally demonstrated. Differential can be used distinguish discrepancy two signals.

We propose and demonstrate a novel bit-by-bit code scrambling technique based on time domain spectral phase encoding/decoding (SPE/SPD) scheme using only single modulator to simultaneously generate decode the hopping sequence DPSK data for secure optical communication application. In experiment, 2.5-Gb/s has been generated, decoded securely transmitted over 34 km by five 8-chip, 20-Gchip/s Gold codes with prime-hop patterns. The proposed can rapidly reconfigure data, thus it is very robust...

The generation of 10 GHz triangular, sawtooth, flat-top, sinusoidal and doublet waveforms based on the manipulation frequency comb from a continuous-wave laser source by single-stage dual-drive Mach-Zehnder modulator is experimentally demonstrated.

Since the frequency offset estimation (FOE) must be implemented before subcarrier de-multiplexing and chromatic dispersion compensation (CDC) for digital multiplexing (DSM) signals, traditional FOE algorithms single carrier transmission is no longer suitable. Here, we propose a hardware-efficient blind solution DSM signals by monitoring spectral dips in domain. With use of smoothing filter, accuracy can significantly increased. Moreover, identify that proposed method robust to various...

The instability of optical phase chaos synchronization between semiconductor lasers under master–slave open-loop configuration is investigated. difference the master and slave obtained analyzed in experiment by heterodyne detection Hilbert transform, simulation solving rate equations. results show that only maintains a short duration time then jumps to another value. A statistical analysis shows both jumping values are random, proving unstable. theoretical caused external cavity mode laser.

The ε -Ga 2 O 3 thin film was grown on sapphire substrate by using metalorganic chemical vapor deposition (MOCVD) method, and then used to fabricate a deep-ultraviolet (DUV) photodetector (PD). shown good crystal quality decent surface morphology. Irradiated 254-nm DUV light, the displayed optoelectronic performance high wavelength selectivity, such as photoresponsivity ( R ) of 175.69 A/W, detectivity D *) 2.46 × 10 15 Jones, external quantum efficiency (EQE) 8.6 4 % photocurrent-intensity...

We propose a novel orthogonal modulation format with differential phase-shift keying (DPSK) and code-shift (CSK) to improve transmission capacity of the optical code-based communication system. A 2-bit/symbol 10-Gb/s system DBPSK/binary-CSK is demonstrated.

In this study, we have proposed and numerically demonstrated that the bias current of a semiconductor laser cannot be used as key for optical chaos communication, using external-cavity lasers. This is because chaotic carrier has signature relaxation oscillation, whose period can extracted by first side peak carrier’s autocorrelation function. Then, approximately cracked, according to well-known relationship between solitary laser. Our simulated results shown cracked eavesdropper could...

A mobile fronthaul approach that can facilitate 96 channels of 20MHz 64QAM LTE formatted signals over 20km fibre has been demonstrated for the first time, due to centralized pre-compensation downlink and post-compensation uplink in BBU, RRH sustains neat.

We numerically demonstrate the generation of wide-band laser chaos with flat power spectrum in a 2D circular-side hexagonal resonator (CSHR) microlaser subject to long-cavity optical feedback. The bandwidth and flatness chaotic are investigated under different bias currents feedback rates. Under low current, an optimized rate increases obviously as raising current flatten simultaneously. high gradually tends toward stabilization, corresponding less than 5 dB. compare spectra small-signal...