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In this paper, a free-space optical (FSO) communication system with supercontinuum source generated by dispersion shift fiber (DSF) from pulsed light modulated by optical switches is designed and constructed. In addition, the experimental results of free-space optical communication between broadband and narrowband light source are compared. Verifying the feasibility of broad-spectrum FSO communication...
The non-line-of-sight ultraviolet single-scatter approximate model is usually used to study the channel characteristics and system performance due to its simplification. In this paper, a performance evaluation system based on the approximate model is established, which includes four aspects, namely, packet error rate, average transmitting power, bandwidth utilizing efficiency and data transmission...
An all-optical multilevel amplitude regenerator is optimized based on the transmission response of a nonlinear optical loop mirror (NOLM). Three regenerative regions defined by the power-transfer-function (PTF) slope of less than 1 are obtained, and noise suppression is shown for a PAM4 signal. Using amplitude dithering we were able to experimentally characterize the transfer function slope and confirm...
In this paper we demonstrate the 4 level pulse amplitude modulation (PAM-4) signal generation through a silicon Mach-Zehnder modulator. The baud speed of the PAM-4 signal generation is characterized up to 32 Gbaud (64Gb/s). And we have measured the device's bit error rate (BER) up to 32 Gbaud and the spurious free dynamic range (SFDR) of the distortion component of the modulated light.
Single event effect susceptibility of industrial MCUs and key drive chips of several commercial transceivers are studied based on heavy ions and pulse laser methods. Based on the testing results, the performance of receive chips are better than transmit chips or transceiver chips, and the threshold values of transmit chips or transceiver chips are between 30 and 37MeV.cm2/mg. However, the MCUs are...
A novel optical pulse generator with high-rate and low-jitter is proposed based on the optoelectronic oscillator using a cascaded polarization modulator and phase modulator. Optical pulses with 10 GHz repetition rate and 29 ps width are demonstrated. According to the single-sideband phase noise of the generated microwave signal, 169 fs time jitter of the generated pulses in the 100 Hz to 1 MHz frequency...
High extinction ratio is needed in high precision Optical Time Domain Reflectometer (OTDR) to enlarge the dynamic range. By transmitting part of pulse signal modulated by a Mach-Zehnder (MZ) optical modulator back to the input of the modulator via a feedback circuit, the pulse signal can be multi-modulated by one MZ optical modulation. And this technique offers great enhancements in the performance...
We propose a novel optical encoding scheme based on spectral phase encoding, in which optical codes are randomly selected from a code set for code hopping. The security performance is analysed. It can achieve the identical security level with short hopping pattern, efficiently improving the system resources.
A photonic-based phased array antenna (PAA) with ultra-fast beam scan is proposed and experimentally demonstrated using dispersion-based true time delay lines. The ultra-fast angle scan is realized using an ultra-fast wavelength-swept laser source which is constructed by a gated multi-wavelength laser (MWL) and a dispersion compensation fiber (DCF). The wavelength switching time is about several nanoseconds...
We demonstrate a silicon PAM-4 optical modulator, which is based on a symmetric Mach-Zehnder interferometer. Two uncorrelated binary electrical signals with different peak-to-peak voltages are applied to the phase shifters of the silicon optical modulator. Accordingly, two different phase shifts are generated in the two arms. After the permutation, there are totally four phase differences between...
A pulse amplitude modulation with 4 levels (PAM-4), generated by optical superimposition, is first proposed and experimentally demonstrated for visible light communication (VLC). It can overcome the shortcomings of the PAM-4 signals generated in the electrical domain, with enhanced tolerance to the modulation nonlinearities of a light emitting diode (LED). A proof-of-concept experiment employing two...
In this paper, we develop two joint routing and resource allocation algorithms for stealth and ordinary services in optical networks. The transmission of stealth service needs to be hidden in ordinary services to achieve a better performance in privacy. Two heuristic algorithms construct paths for stealth and ordinary services base on the different routing methods. The proposed algorithms improve...
Spectral phase coding by using 0/π-phase-shift and ±π/2-phase-shift are thoroughly studied. The security vulnerability and improvement are analysed by evaluating the encoded signal. ίπ/2-phase-shift spectral phase coding can guarantee the security by hiding the optical code in the encoded signal. In addition, coding performance of both spectral phase coding techniques is investigated by measuring...
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