Based on the technique of master oscillator power amplifier (MOPA), a two-stage ytterbium-doped fiber amplifier
(YDFA) with all-fiber structure is theoretically simulated. The seed signal operating at the wavelength of 1064 nm has
the characteristic of high repetition rate (10 MHz), ultrashort pulse duration (10 ps), low signal power input (20μW) and
single longitudinal mode. The gain (and amplification stimulation emission power) is calculated at the different pump
powers and gain fiber lengths of YDFA pumped by 975 nm. In addition, the amplifications at the different signal power
inputs (1-25μW) are also simulated. The numerical results can be used to optimize the YDFA.
Three-dimensional imaging laser radar (3-D ladar) is widely used in area of modern military, scientific research,
agriculture and industry. Because of its many features such as angle-angle-range capturing, high resolution, anti-jamming
ability and no multipath effect ,but it has to scan for target searching, acquiring and tracking. This paper presents a novel
probability model of target acquiring which provides a theoretical basis for optimizing the scanning mechanism. The
model combines space and time, target moving velocity and ladar scanning velocity together. Then the optimum
scanning mechanism to obtain the maximum probability of acquisition and associated with different targets can be
gained. The result shows that this model provides a method to optimize parameter for designing of the scanner.