IEEE Aerospace and Electronic Systems Magazine - July 2020 - 9

Credit: Jet Propulsion Laboratory

Fortunately, for the last few years, the DSN has been
anticipating the launch of a large number of small satellites
into deep space. For this reason, the DSN has proactively
introduced a number of initiatives to make the network
small-satellite friendly. This study takes note of such initiatives and provides accompanying recommendations. It also
looks at existing deep space SmallSat communication systems, their communications-related shortcomings for serving the deep space science community, and recommends
improvements to overcome such limitations. Often, the proposed technological and methodological improvements
encompass both the space segment and the ground segment.
The approach of the study is described as follows.
Identification of current communication architectures, including various forms of network types, and
capabilities compatible with the objective of the
study for both standalone and mother-daughter
architectures (proximity).
Assessment of navigation needs (standalone and
proximity operations).
Assessment of the communication architecture performance for a range of destinations and applications.
Identification of any gaps in capability.
The study product is a set of recommendations to
NASA3 and the deep-space SmallSat community. The
main thrust of these recommendations is investment in
3

The recommendations of this study can potentially be used by other
space agencies, such as the ESA, the Japan Aerospace Exploration
Agency (JAXA), etc.

JULY 2020

technology, such as radios, antennas, protocols, and methodologies. This study has been performed with the following constraints in mind.
a) Spectrum availability controlled via International
Telecommunications Union (ITU) regulations.
b) Ground segment capabilities, such as aperture performance, waveform support, navigation solutions,
and concept of operations (CONOPS), etc.
c) Space segment capabilities, such as solar panel size,
antenna size, radio functionality, CONOPS, etc.
While cost is an important element of any technological investment, this study does not directly address cost.
Despite that, only options that were deemed practical
from an infusion point of view were considered, which
provided an indirect reference to cost.

DEFINITIONS AND THE GROUND RULES
The term SmallSat loosely refers to a satellite that is a
size/weight between a 6U4 CubeSat and a 100-kg-drymass spacecraft. Unlike primary missions, which tend to
be expensive and carry a variety of science payloads as
well as assuming a low risk posture, SmallSats in deep
space tend to be more focused and carry a limited number
of science payloads and assume more risk. A SmallSat
may have a direct-to-Earth (DTE) link allowing it to communicate with Earth without the need to depend on a relay
4

U is a unit of size for CubeSats equal to a cube of 10 x 10 x 10 cm3.

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IEEE Aerospace and Electronic Systems Magazine - July 2020

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