As human beings expand the research in unknown areas constantly, the deep space exploration has become a
hot research topic all over the world. According to the long distance and large amount of information transmission
characteristics of deep space exploration, the space laser communication is the preferred mode because it has the
advantages of concentrated energy, good security, and large information capacity and interference immunity. In a variety
of laser source, fibre-optical pulse laser has become an important communication source in deep space laser
communication system because of its small size, light weight and large power. For fiber lasers, to solve the contradiction
between the high repetition rate and the peak value power is an important scientific problem. General Q technology is
difficult to obtain a shorter pulse widths, This paper presents a DFB semiconductor laser integrated with
Electro-absorption modulator to realize the narrow pulse width, high repetition rate of the seed source, and then using a
two-cascaded high gain fiber amplifier as amplification mean, to realize the fibre-optical pulse laser with pulse width 3ns,
pulse frequency 200kHz and peak power 1kW. According to the space laser atmospheric transmission window, the
wavelength selects for 1.06um. It is adopted that full fibre technology to make seed source and amplification, pumping
source and amplification of free-space coupled into fiber-coupled way. It can overcome that fibre lasers are vulnerable to
changes in external conditions such as vibration, temperature drift and other factors affect, improving long-term stability.
The fiber lasers can be modulated by PPM mode, to realize high rate modulation, because of its peak power, high
transmission rate, narrow pulse width, high frequency stability, all technical indexes meet the requirements of the
exploration of deep space communication technology.
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