In this paper,a Radio Over Fiber (ROF) system with a Digital Pre-Distorter (DPD) for WCDMA signal transmission is investigated.A Look-Up Table (LUT) based DPD and a Memory Polynomial (MP) DPD are applied in the ROF link so as to suppress the out-of-band spurious spectrum and improve the transmission performance.The experimental results show that the out-of-band emission due to existence of the third-order Inter-Modulation Distortion (IMD3) is obviously sup-pressed by these two DPD.An Adjacent Channel Power Ratio (ACPR) improvement of 8 dB is ob-tained for a single-carrier WCDMA signal transmission.These two DPD have equal ability in lin-earization of the ROF system for a three-carrier WCDMA signal transmission.There is no apparent memory effects exist in the ROF link.
We present the measurement of the third-order nonlinearity of Bi_2O_3-B_2O_3-BaO glasses using the single Z-scan method with femtosecond laser pulses at 750-850 nm.Both third-order nonlinear refractionγand two photon absorption coefficient β are investigated.Theγshows an increasing tendency with increasing BaO content,and the largest value is estimated to be 7.2×10^(-14) cm^2/W,which is as large as those of chalcogenide glasses.The dependence ofβon the normalized photon energy is studied.
