Satellite-to-ground quantum-limited communication using a 50-kg-class microsatellite

Abstract

Recently, the increasing availability of small-size satellites as well as low-cost launches is leading to a rapid growth in the number of satellite-constellation programs, in which thousands of satellites orbiting in a Low Earth Orbit (LEO) work in concert with each other for remote sensing and communications with coordinated ground coverage. Data-intensive satellite sensors mounted in such a constellation produce a large amount of information to be transmitted to the ground in a short time, which requires high capacity communications.However, conventional satellite communications based on microwave frequency bands will struggle to provide the needed capacity because these bands are already congested and severely regulated, and hence the frequency licensing process is lengthy. In the last decade, laser communication (lasercom) has evolved as a promising alternative for high-capacity data links from space [1-11], overcoming microwave communication in several key aspects, such as much higher data rates, being able to use an unregulated spectrum, ultra-low inter-channel interference, smaller and lighter terminals, and power-efficient transmission. In fact, the feasibility of satellite lasercom has been demonstrated by many space missions so far. However, they were based on dedicated bulky satellites of large size, typically several hundred kg with the lasercom terminal mass over 10 kg.Information security is also becoming an urgent issue in satellite constellations, because the amount of critical and valuable data to be communicated is increasing. Space quantum communication can enhance not

Satellite-based links for quantum key distribution: beam effects and weather dependence

“…They can take advantage of the satellite technology and the optical communication methods developed in the last decades in the classical case. Various feasibility studies had addressed this topic in the last twenty years [8][9][10][11] and several experiments have definitely proved that the technology involved is ready for deployment [12][13][14][15][16].Optical satellite-based links have the important drawback of being strongly dependent on the weather conditions [17][18][19][20]. The presence of turbulent eddies and scattering particles like haze or fog generates random fluctuations of the relative permittivity of the air, on different length-and time-scales.…”

Mars Colonization: Beyond Getting There

“…Ongoing advances in nanotechnology and materials engineering enhanced reliability and expanded functionality of contemporary electronics and robotics while reducing device mass, volume, and power consumption . The affordability of small space assets has enabled greater exploration of space, allowing space agencies, universities, and commercial players to collect vital information about extraterrestrial environments in which space assets and living subject will be required to operate, guiding and informing the development of colonization programs …”

“…Modular Martian settlement (artistic representation). Several alternative modular concepts have been proposed, including one by Mars One …”

“…[10] The affordability of small space assets has enabled greater exploration of space, allowing space agencies, universities, and commercial players to collect vital information about extraterrestrial environments in which space assets and living subject will be required to operate, guiding and informing the development of colonization programs. [11] Is it time to go extra-terrestrial? Mars One program has been operating since 2012 and, considering the present level of financial Colonization of Mars: As humans gradually overcome technological challenges of deep space missions, the possibility of exploration and colonization of extraterrestrial outposts is being seriously considered by space agencies and commercial entities alike.…”

“…Several alternative modular concepts have been proposed, including one by Mars One. [11] infrastructure and sustain the most fundamental needs of the colony, and not scientific instruments for greater Mars exploration. However, it should be noted that with recent advancements in miniaturized, energy-efficient electronic and robotics devices, it may in principle be possible to deliver a highly functional yet compact automated laboratory to Mars.…”