  We describe the realization and characterization of a compact, autonomous
fiber laser system that produces the optical frequencies required for laser
cooling, trapping, manipulation, and detection of $^{87}$Rb atoms - a typical
atomic species for emerging quantum technologies. This device, a customized
laser system from the Muquans company, is designed for use in the challenging
operating environment of the Laboratoire Souterrain \`{a} Bas Bruit (LSBB) in
France, where a new large scale atom interferometer is being constructed
underground - the MIGA antenna. The mobile bench comprises four frequency-agile
C-band Telecom diode lasers that are frequency doubled to 780 nm after passing
through high-power fiber amplifiers. The first laser is frequency stabilized on
a saturated absorption signal via lock-in amplification, which serves as an
optical frequency reference for the other three lasers via optical phase-locked
loops. Power and polarization stability are maintained through a series of
custom, flexible micro-optic splitter/combiners that contain polarization
optics, acousto-optic modulators, and shutters. Here, we show how the laser
system is designed, showcasing qualities such as reliability, stability, remote
control, and flexibility, while maintaining the qualities of laboratory
equipment. We characterize the laser system by measuring the power,
polarization, and frequency stability. We conclude with a demonstration using a
cold atom source from the MIGA project and show that this laser system fulfills
all requirements for the realization of the antenna.
