Optical payload design for downlink quantum key distribution and keyless communication using CubeSats

Quantum key distribution is costly and, at the moment, offers low performance in space applications. Other more recent protocols could offer a potential practical solution to this problem. In this work, a preliminary optical payload design using commercial off-the-shelf elements for a quantum communication downlink in a 3U CubeSat is proposed. It is shown that this quantum state emitter allows the establishment of two types of quantum communication between the satellite and the ground station: quantum key distribution and quantum keyless private communication. Numerical simulations are provided that show the feasibility of the scheme for both protocols as well as their performance. For the simplified BB84, a maximum secret key rate of about 80 kHz and minimum QBER of slightly more than $0.07\ \%$ is found, at the zenith, while for quantum private keyless communication, a 700 MHz private rate is achieved. This design serves as a platform for the implementation of novel quantum communication protocols that can improve the performance of quantum communications in space.Comment: 24 pages, 9 figure

Annual Report of Undergraduate Research Fellows from August 2014 to May 2015

Annual Report of Undergraduate Research Fellows from August 2014 to May 2015

IAU Dark and Quiet Skies, UNOOSA, NoirLabs, SATCON2, International Law Working Group Report

International Law Working Group of the IAU's Dark and Quiet Skies Conference; objective to advise the UN Committee on the Peaceful Use of Outer Spac

Dark and Quiet Skies II Working Group Reports:

This Report presents the main results of the Conference “Dark and Quiet Skies for Science and Society II” which took place on-line on 3–7 October 2021. This conference was the logical follow-up of the first one, organized as an on-line workshop with the same title on 5–9 October 2020. Both conferences were co-organized by UNOOSA, IAU and the Government of Spain and were well attended. The focus of the second conference was about the feasibility of implementing the recommendations presented by the first one in its extensive report. The main qualifying difference between the first and the second conferences was a more explicit involvement of the industrial stakeholders and of space policy experts, whose contributions were instrumental in presenting a credible review of the proposed mitigating measures as well as of possible regulatory guidelines

Annual Report of Undergraduate Research Fellows from August 2016 to May 2017

Annual Report of Undergraduate Research Fellows from August 2016 to May 2017

The Space to Lead

204 hlm.; 21 cm

The Impact of a Nuclear Disturbance on a Space-Based Quantum Network

Quantum communications tap into the potential of quantum mechanics to go beyond the limitations of classical communications. Currently, the greatest challenge facing quantum networks is the limited transmission range of encoded quantum information. Space-based quantum networks offer a means to overcome this limitation, however the performance of such a network operating in harsh conditions is unknown. This dissertation analyzes the capabilities of a space-based quantum network operating in a nuclear disturbed environment. First, performance during normal operating conditions is presented using Gaussian beam modeling and atmospheric modeling to establish a baseline to compare against a perturbed environment. Then, the DEfense Land Fallout Interpretive Code software and computational fluid dynamics study the effect of a nuclear explosion on the surrounding environment. Finally, these sources of noise are combined to estimate the degradation of quantum states being transmitted through a nuclear disturbed environment. It is found that the effects of a nuclear environment on a quantum network is a function of the height of blast, the explosive yield, and the network design. Debris lofted into the atmosphere during a surface blast dissipate after a couple of hours, yet the concentration is initially high and results in heavy signal loss. The nuclear fireball produced additional background light interference that scatters into the receiver\u27s detector from tens of seconds to a couple of minutes, causing excessive noise in the detector. All these effects are likely to impede a quantum network’s ability to distribute quantum information between a ground station and low Earth orbit satellite for approximately one transmission period. Afterwards, by the next satellite pass, normal operation is expected to resume. These results provide the operational capabilities of space-based optical quantum networks following a nuclear explosion. The model can be expanded to model satellite-based quantum networks in other harsh atmospheric environments

An Inference about Interference: A Surprising Application of Existing International Law to Inhibit Anti-Satellite Weapons

This article presents a thesis that most readers will find surprising, in an effort to develop a novel, simultaneous solution to three urgent, complex problems related to outer space. The three problems are: a) the technical fact that debris in outer space (the accumulated orbital junk produced by decades of space activities) has grown to present a serious hazard to safe and effective exploration and exploitation of space; b) the strategic fact that many countries (notably the United States, China and Russia, but others, too) continue to demonstrate a misguided interest in pursuing anti-satellite weapons, which can jeopardize the security of space; and c) the political fact that attempts to provide additional legal regulation of outer space (via new bilateral or multilateral international agreements) have failed, with little prospect for prompt conclusion of meaningful new accords. The proposed solution is to adapt existing international law in an unforeseen way. Specifically, numerous current and historical arms control treaties provide for verification of parties’ compliance via “national technical means” (NTM) of verification, which prominently include satellite-based sensory and communications systems. These treaties routinely provide protection for those essential space assets by requiring parties to undertake “not to interfere” with NTM. The argument developed here is that additional tests in space of debris-creating anti-satellite weapons would already be illegal, even without the conclusion of any dedicated new treaty against further weaponization of space, because in the current crowded conditions of space, a new cloud of orbital debris would, sooner or later, impermissibly interfere with NTM satellites. If sustained, this thesis can provide a new rationale for opposition to the development, testing, and use of anti-satellite weapons. It a legal reinforcement for the political instincts to avoid activities that further undercut the optimal usability of outer space, and it demonstrates how creative re-interpretation of existing legal provisions can promote the advancement of the rule of international law, even in circumstances where the articulation of new treaties is blocked