We propose a new Polarization-OTDR system to measure the distribution of birefringence. The evolution of state of
polarization(SOP) is detected utilizing the coherent Rayleigh scattering light in two fibers (Reference fiber and fiber
under test). The birefringence is calculated based on Jones matrix, and the trace of Jones matrix can describe the
magnitude of birefringence. The resolution and SNR of coherent Polarization-OTDR is significantly improved.
In this paper, we propose a new structure to measure the temperature and the concentration at the same time.
Semiconductor absorption material is used for measuring the temperature; and fiber bundles are used as input and
output fibers. Right-angle prisms, as reflectors, are used at the end of the fiber bundles. The concentration is measured based on the changing of refractive index.
We propose a POTDR setup and investigate the Rayleigh scatter and Fresnel refection. A piezoelectric polarization
controller (PPC) is applied in this setup. Based on the transfer matrix theory of the PPC, the state of polarization (SOP)
of the Fresnel reflection is analyzed under different temperature. In the experiment, we find that when any part of the
fiber is affected by the temperature, the SOP of Fresnel reflection will be changed.
We investigate the polarization-dependent mode gains and polarization rotation (PR) of the semiconductor optical
amplifier in pump-probe scheme, and find that the relationship between polarization rotation (PR) and mode gains keeps
well under different pump power. Thus we can simply obtain the PR angle by measurement of the mode gains. Choosing
suitable injected current we realize the orthogonal polarization rotation by pump laser with power of ~3.5 mW. Then we
propose a novel digital polarization encoding scheme and perform it well in a 10-km fiber transmission system with data
rate at 2.5 G-bit/s, which is promising to promote the optical power-equalized encoding communications.
ww have presented and demonstrated the dual-wavelength signal storage in Dual-Loop Optical Buffer. The output equality of dual wavelength signals will decrease for unbalanced gain and phase shift. The problem can be resolved by power equalization using the saturation character of SOA. The data packets with2 × 2.5Gb/s can be buffered in DLOB for 16 cycles corresponding to 20 .The Extinction Ratio of the output packet is 8dB while the S/N is 8.1dB.
We introduce a phenomenological model to describe polarization-sensitive SOAs which is composed of a partly linear
polarizer, a retarder, and a polarization independent amplifier. It shows that any input optical vector of signal will first be
partly linearly polarized, then rotate around S1-axis of the Poincaré sphere for θ, and finally be amplified equably. Then we
investigate and experimentally demonstrate the relationship between polarization rotation (PR) and mode gains. We further
obtain two necessary conditions for the valuable orthogonal polarization rotation (OPR), and then perform a power-equalized
OPR by optical-electric synchronous control of the SOA. The polarization duration time is ~10 ns which is applicable to
high-speed polarization state generation.