CTA telescopes as deep-space lasercom ground receivers

TL;DR

This paper investigates the potential of using Cherenkov Telescope Array telescopes as cost-effective, large-aperture ground stations for deep-space optical communication, demonstrating technical feasibility and potential benefits.

Contribution

It proposes repurposing Cherenkov telescopes for optical communication ground stations, highlighting cost savings and performance improvements over traditional designs.

Findings

Feasibility of using Cherenkov telescopes for deep-space optical links.

Simulations show potential cost reductions and performance gains.

Adaptations can optimize telescopes for communication purposes.

Abstract

The amount of scientific data to be transmitted from deep-space probes is very limited due to RF-communications constraints. Free-space optical communication can alleviate this bottleneck, increasing data rate while reducing weight, mass and power of communication onboard equipment. Nevertheless, optimizing the power delivery from spacecraft to Earth is needed. In RF communications, the strategy has been to increase the aperture of ground terminals. Free-space optical communications can also follow it, as they share the limitation of low power received on Earth. As the cost of big telescopes increases exponentially with aperture, new ideas are required to maximize the aperture-to-cost ratio. This work explores the feasibility of using telescopes of the future Cherenkov Telescope Array as optical-communication ground stations. Ground-based gamma-ray astronomy has the same power limitation, hence Cherenkov telescopes are designed to maximize receiver's aperture with minimum cost and some relaxed requirements. Both critical issues of the reutilization and possible adaptations of the telescopes to optimize them for communications, and telescopes simulations and numerical computations of several link budgets applied to worst-case scenarios are discussed, concluding that the proposal is technically feasible and would bring important cost reductions and performance improvements compared to current designs for deepspace optical ground stations.