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An all-optical frequency-upconversion based on fractional talbot effect is experimentally reported. The 2.5-Gb/s baseband signal carried on 10GHz pulse trains is upconverted to 40GHz millimeter wave after 18.49km transmission via repetition frequency multiplication of pulse trains. The phase noise of the 40GHz is as well as −92dBc/Hz at 10kHz frequency detuning. This scheme can operate in 60GHz band by employing the appropriate fiber length based on fractional talbot effect.

A novel scheme to realize all-optical logic gates is proposed bases on nonlinear polarization rotation (NPR) in high nonlinear fiber (HNLF). Two optical signals A and B with return-to-zero data format are injected into the HNLF together with a continuous wave C. Thanks to the optical power variation in HNLF, nonlinear birefringence will be induced between the two polarization axes. Thus it results in the nonlinear polarization rotation of the lightwave in the HNLF. Both the optical signal and continuous wave are filtered out at the output of HNLF using optical band-pass filter. By adjusting the optical power and polarization of the optical signal as well as the polarization of the polarizer with respect to the polarization of optical signal/continuous wave, multiple all-optical logic gates can be realized. Theoretical analysis of the simultaneously realization of the multiple optical logic gates based on NPR in HNLF is provided. And we demonstrated the feasibility of the scheme by realizing all optical “and”, “not”, “nxor”, “A • B”, “A• B ”, half-adder and half-subtracter at 10Gb/s operation.

40 Gb/s optical demultiplexing with amplitude regeneration is demonstrated based on data pump fiber-optical parametric amplification while a 10 GHz short pulse is used as the probe. Four 10 Gb/s output channels with at least 14 dB extinction ratio enhancement and an average 5.5 Q factor is obtained after demultiplexing.

We propose a novel technique to achieve optical frequency up-conversion in millimeter wave band without any local microwave oscillator. By utilizing injection locking of Febry-Perot Laser diode, a suitable negative dispersion device and polarization interferometer, a 2.5Gb/s baseband signal is frequency up-conversion to a subcarrier modulation signal at 30.8GHz.

The optical pulse trains at a multiplied repetition frequency is generated by Fractional Talbot effects in optical fiber. The principles of Talbot effects and Fractional Talbot effects in fiber are analyzed in this paper. The 20GHz, 40GHz and 50GHz optical pulse trains are obtained from the original pulse trains with 2.8ps width at 10GHz repetition frequency. An optical pulse at 40GHz repetition frequency is also produced by upshifting the repetition frequency of 5GHz pulse trains. The degradation of 40GHz and 50GHz pulse trains is discussed by spectrum analysis of the pulse trains and some methods are proposed to enhance the performance of the pulse trains.

A simultaneous optical signal extracting and erasing scheme is presented by utilizing four-wave mixing (FWM) in optical fiber. Two synchronized gate and negation gate pulses are used as control signal, which are coupled with data stream and produce FWM effect in high nonlinear fiber (HNLF). Through filtering the idler light generated between each control signal and data stream, simultaneous signal extracting and erasing functions can be obtained. Experimental results are successfully demonstrated with NRZ data format at 10 Gbit/s. This system is able to operate at higher bit rates and other data modulation formats.

An all-optical regenerator based on single pump fiber-optic parametric amplifier (FOPA) is demonstrated and assessed experimentally. The static power transfer function of the FOPA is measured, and a clear saturation behavior is observed with the saturation much easier to achieve at a larger the pump power. The regenerator performance is further investigated by changing parameters of the input signal. Results show that the SNR and timing jitter of the regenerated signal is maintained around 15 dB and 2 ps regardless of the transmission distance of the input signal, and above 7 dB SNR improvement can be achieved when the input SNR is within the range of 3 to 10 dB. The regeneration performance is also tested by varying the input signal wavelength, and at least 6 dB SNR improvement is obtained within the range of the gain bandwith of the single pump FOPA.

A time- and wavelength-interleaved (T- W-interleaved) optical pulse source based on optoelectronic oscillator is presented. By utilizing spectral slicing, a multi-loop configuration is formed in OEO system, which can effectively suppress side-modes. In addition, this configuration is able to generate multi-wavelength optical pluses which can be arranged T- W-interleaved optical pulse stream at different nodes. In this system, 10-ps-wide optical pulses at 5GHz repetition rate are generated with 1ps timing jitter (in the 100Hz-1MHz range) and -100dBc/Hz spurious modes suppression, Along with the optical outputs, 5GHz electrical signal with low phase noise (-113dBc/Hz at 10kHz offset from the carrier) is also obtained.

Short locking and unlocking time is essepecially important in the packet clock recovery, as it determines the network resource utilization. This paper presents a novel 10-GHz all-optical packet clock extractor with ultrafast locking and unlocking time via self-phase modulation (SPM) effect of the semiconductor optical amplifier (SOA). Low finesse Fabry-Perot (F-P) filter and a saturated SOA, in cascade, are used to directly extract the packet clock from the data stream. An optical bandpass filter(OBPF) is used to filter out the red-shifted parts of the packet clock in order to reduce the locking and unlocking time. We analytically investigate the impact of the locking and unlocking time thanks to the self-gain modulation (SGM) effect and self-phase modulation(SPM) effect induced by the SOA, and demonstrate 10GHz clock extraction with the establishing time of 200ps and vanishing time of 600ps experimentally.

We demonstrate a tunable chromatic dispersion (CD) compensation technique using a semiconductor optical amplifier (SOA) and a coil of dispersion compensation fiber (DCF). Based on cross-phase modulation (XPM) in the SOA, the transient chirp of the received signal can be adjusted by tuning the drive current of the SOA and the power of clock pulse. In this way, a 10-Gbit/s tunable CD compensation setup, ranging from -40ps/nm to 60ps/nm, is realized without changing the length of the DCF.

A time- and wavelength-interleaved optical pulse source, which is based on spectral slicing and dispersion management, is proposed and experimentally demonstrated. The pulse source has a simple configuration, and both the repetition rate and the wavelength channels can be tuned easily.

A novel 10Gbit/s all-optical packet clock extractor, which comprises a Fabry-Perot (F-P) filter and a semiconductor optical amplifier (SOA), is proposed in this paper. Low Finesse Fabry-Perot (F-P) filter was used to directly extract the packet clock from the data packet stream, which ensures that the clock locks fast and vanishes quickly. The clock, amplitude modulated as a result of low-Q filter, then goes into SOA to reduce the low-frequency amplitude noise. The impact of F-P filter and SOA on the locking and unlocking time of the packet clock is theoretically analyzed. The result shows that the locking time is reduced while the unlocking time is increased, due to the self-gain modulation (SGM) effect. We demonstrate instantaneous 10.075GHz clock extraction experimentally with the establishing time of about 8 code-periods and vanishing time of about 22 code-periods.

We demonstrate a novel 40-Gb/s all-optical serial to parallel converter (AOSPC), which can convert 40-Gb/s serial optical signals to 4-channel 10-Gb/s parallel optical signals. Moreover, based on the sequential multi-wavelength conversion the AOSPC shows the regeneration ability.