Sheng Xinzhi

Influence of Deformation Holes on Properties of Photonic Crystal Fibres

Deformation of some air holes often occurs during the fabrication process of photonic crystal fibres (PCFs). Effects of the location and size of deformation holes on the properties of actual triangular lattice PCFs are investigated in detail. Numerical results demonstrate that the properties of PCFs, especially birefringence, are sensitive to the location and size of deformation holes. These would be very helpful to improve the fabrication technique of the PCF and also offers an efficient way to design high birefringence PCF.

A novel scheme to measure the power of AC system with FPGA

Nowadays, most digital power measurement is based on DSP. This paper proposed a field programmable gate array (FPGA) implemented digital elements in the power measurement of AC system. The main difference is that FPGA allow concurrent operation, enabling high performance which levels achieved are orders of magnitude greater than those obtained with traditional digital signal processor. The design scheme has been developed using a hardware description language (VHDL), which provides great flexibility and technology independence. The measuring system has been implemented as simple as possible, while maintaining good accuracy and dynamic response. Simulation and experimental results show the feasibility of our scheme.Nowadays, most digital power measurement is based on DSP. This paper proposed a field programmable gate array (FPGA) implemented digital elements in the power measurement of AC system. The main difference is that FPGA allow concurrent operation, enabling high performance which levels achieved are orders of magnitude greater than those obtained with traditional digital signal processor. The design scheme has been developed using a hardware description language (VHDL), which provides great flexibility and technology independence. The measuring system has been implemented as simple as possible, while maintaining good accuracy and dynamic response. Simulation and experimental results show the feasibility of our scheme.

Influence of Multi-Cascaded Semiconductor Optical Amplifiers on the Signal in an Energy-Efficient System

Signal impairment is experimentally studied by using the extinction ratio (ER), error bit rate (BER) and optical spectrum in a three-cascaded semiconductor optical amplifier (SOA) setup. The signal with the ER of 13 dB and BER of < 10−9 is achieved after the signal passing through the cascaded SOAs. With the results obtained from the experiment, we confirm that the three-cascaded SOAs used to compensate for power in the optical transmission can be accepted. This experimental result also offers the possibility of achieving a higher throughput of multiplane architecture by exploiting three switching domains instead of two switching domains in the energy-efficient design of a scalable optical multi-plane interconnection architecture. The space switches in output ports of multi-plane interconnection architecture can be improved to N = 32 × 32 × 32 = 32768.

Experimental Investigation of All-Optical NRZ-DPSK to RZ-DPSK Format Conversion Based on TOAD

We propose and experimentally demonstrate a novel all-optical non-return-to-zero differential-phase-shift-keying (NRZ-DPSK) to return-to-zero differential-phase-shift-keying (RZ-DPSK) format conversion scheme. This scheme is based on the terahertz optical asymmetric demultiplexer (TOAD). A 10 Gb/s converted RZ-DPSK signal is obtained with a wide duty cycle tuning range from 16% to 66%. For all converted RZ-DPSK signals, the receiver sensitivities at BER of 10−9 are 0.4 to 1.7 dB higher compared with the original NRZ-DPSK signal. The clear and open eye diagrams are presented to demonstrate the high quality format conversion performance. Moreover, the optical spectra show that this conversion is in a wavelength-preserving operation.

All-Optical Time Slot Interchange Using a Cascaded Optical Buffer

A novel scheme of all-optical time slot interchanger employing two cascaded re-circulating optical buffers based on nonlinear polarization rotation in semiconductor optical amplifiers is proposed. The experimental system exhibits full interchangeable capability on three 512-bit packets at 10 Gbits/s. Theoretically, each packet length is up to 123ns with the maximum buffer depth 30%.

Laser ultrasound detecting experiment with fiber Michelson interferometer

A laser ultrasound stably detecting has been demonstrated by a new type fiber optic Michelson interferometer with 3times3 direction coupler. The experimental result suggests that its able to sense an ultrasound vibration frequency from 10 KHz to 1.5 MHz.