NASA is developing a space power system using lightweight, flexible photovoltaic devices originally developed for use here on Earth to provide low cost power for spacecraft. The Lightweight Integrated Solar Array and anTenna (LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. The LISA-T system is deployable, building upon NASA's expertise in developing thin-film deployable solar sails such the one being developed for the Near Earth Asteroid Scout project which will fly in 2018. One of the biggest challenges for the NEA Scout, and most other spacecraft, is power. There simply isn't enough of it available, thus limiting the range of operation of the spacecraft from the Sun (due to the small surface area available for using solar cells), the range of operation from the Earth (low available power with inherently small antenna sizes tightly constrain the bandwidth for communication), and the science (you can only power so many instruments with limited power). The LISA-T has the potential to mitigate each of these limitations, especially for small spacecraft. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between their need for power and robust communications with the requirements of the science or engineering payload they are developed to fly. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft and CubeSats. The problem is that these CubeSats can usually only generate between 7W and 50W of power. The power that can be generated by the LISA-T ranges from tens of watts to several hundred watts, at a much higher mass and stowage efficiency. A matrix of options are in development, including planar (pointed) and omnidirectional (non-pointed) arrays. The former is seeking the highest performance possible while the latter is seeking GN&C simplicity. Options for leveraging both high performance, 'typical cost' triple junction thin-film solar cells as well as moderate performance, low cost cells are being developed. Alongside, UHF (ultrahigh frequency), S-band, and X-band antennas are being integrated into the array to move their space claim away from the spacecraft and open the door for more capable multi-element antenna designs such as those needed for spherical coverage and electronically steered phase arrays

Boyd, Darren

Carr, John A.

Johnson, Les

NASA is developing a space power system using lightweight, flexible photovoltaic devices originally developed for use here on Earth to provide low cost power for spacecraft. The Lightweight Integrated Solar Array and anTenna (LISA-T) is a launch-stowed, orbit-deployed array on which thin-film photovoltaic and antenna elements are embedded. The LISA-T system is deployable, building upon NASA's expertise in developing thin-film deployable solar sails such the one being developed for the Near Earth Asteroid Scout project which will fly in 2018. One of the biggest challenges for the NEA Scout, and most other spacecraft, is power. There simply isn't enough of it available, thus limiting the range of operation of the spacecraft from the Sun (due to the small surface area available for using solar cells), the range of operation from the Earth (low available power with inherently small antenna sizes tightly constrain the bandwidth for communication), and the science (you can only power so many instruments with limited power). The LISA-T has the potential to mitigate each of these limitations. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between their need for power and robust communications with the requirements of the science or engineering payload they are developed to fly. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft and CubeSats. The problem is that these CubeSats can usually only generate between 7 watts and 50 watts of power. The power that can be generated by the LISA-T ranges from tens of watts to several hundred watts. A matrix of options are in development, including planar (pointed) and omnidirectional (non-pointed) arrays. The former is seeking the highest performance possible while the latter is seeking GN&C (Guidance, Navigation and Control) simplicity. In both cases, power generation ranges from tens of watts to several hundred with an expected specific power greater than 250 watts per kilogram and a stowed power density greater than 200 kilowatts per cubic meter. Options for leveraging both high performance, 'typical cost' triple junction thin-film solar cells as well as moderate performance, low cost cells are being developed. Alongside, both UHF (ultra high frequency) and S-band antennas are being integrated into the array to move their space claim away from the spacecraft and open the door for omnidirectional communications and electronically steered phase arrays

Carr, John

NASA Technical Reports Server

The Lightweight Integrated Solar Array and anTenna 
(LISA-T) - Big Power for Small Spacecraft 
 
NASA is developing a space power system using lightweight, flexible photovoltaic devices 
originally developed for use here on Earth to provide low cost power for spacecraft.  The 
Lightweight Integrated Solar Array and anTenna (LISA-T) is a launch stowed, orbit deployed array 
on which thin-film photovoltaic and antenna elements are embedded.  
 The LISA-T system is deployable, building upon NASA’s expertise in developing thin-film 
deployable solar sails such the one being developed for the Near Earth Asteroid Scout project 
which will fly in 2018.  One of the biggest challenges for the NEA Scout, and most other spacecraft, 
is power.  There simply isn’t enough of it available, thus limiting the range of operation of the 
spacecraft from the Sun (due to the small surface area available for using solar cells), the range of 
operation from the Earth (low available power with inherently small antenna sizes tightly constrain 
the bandwidth for communication), and the science (you can only power so many instruments with 
limited power).  The LISA-T has the potential to mitigate each of these limitations. 
 Inherently, small satellites are limited in surface area, volume, and mass allocation; driving 
competition between their need for power and robust communications with the requirements of the 
science or engineering payload they are developed to fly.  LISA-T is addressing this issue, 
deploying large-area arrays from a reduced volume and mass envelope – greatly enhancing power 
generation and communications capabilities of small spacecraft and CubeSats.  The problem is that 
these CubeSats can usually only generate between 7W and 50W of power.  The power that can be 
generated by the LISA-T ranges from tens of watts to several hundred watts. 
A matrix of options are in development, including planar (pointed) and omnidirectional (non-
pointed) arrays. The former is seeking the highest performance possible while the latter is seeking 
GN&C simplicity. In both cases, power generation ranges from tens of watts to several hundred with 
an expected specific power >250W/kg and a stowed power density >200kW/m3. Options for 
leveraging both high performance, ‘typical cost’ triple junction thin-film solar cells as well as 
moderate performance, low cost cells are being developed. Alongside, both UHF (ultra high 
frequency) and S-band antennas are being integrated into the array to move their space claim away 
from the spacecraft and open the door for omnidirectional communications and electronically 
steered phase arrays. 
 
 
 
 
https://ntrs.nasa.gov/search.jsp?R=20170012314 2019-08-30T16:58:55+00:00Z


The Lightweight Integrated Solar Array and anTenna (LISA-T) - Big Power for Small Spacecraft

IAC-17-C3.4.1 Page 1 of 4 
IAC-17-C3.4.1 
The Lightweight Integrated Solar Array and anTenna (LISA-T) – Big Power for Small Spacecraft 
Les Johnsona*, John A. Carrb, and Darren Boydc  
a Science and Technology Office, NASA George C. Marshall Space Flight Center, Mail Code ST03, Huntsville, 
Alabama 35812, les.johnson@nasa.gov  
 bNASA George C. Marshall Space Flight Center, Mail Code ES44, Huntsville, Alabama 35812 
 c NASA George C. Marshall Space Flight Center, Mail Code ES36, Huntsville, Alabama 35812 
Abstract 
NASA is developing a space power system using lightweight, flexible photovoltaic devices originally developed 
for use here on Earth to provide low cost power for spacecraft.  The Lightweight Integrated Solar Array and anTenna 
(LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. 
The LISA-T system is deployable, building upon NASA’s expertise in developing thin-film deployable solar sails such 
the one being developed for the Near Earth Asteroid Scout project which will fly in 2018.  One of the biggest challenges 
for the NEA Scout, and most other spacecraft, is power.  There simply isn’t enough of it available, thus limiting the 
range of operation of the spacecraft from the Sun (due to the small surface area available for using solar cells), the 
range of operation from the Earth (low available power with inherently small antenna sizes tightly constrain the 
bandwidth for communication), and the science (you can only power so many instruments with limited power).  The 
LISA-T has the potential to mitigate each of these limitations, especially for small spacecraft.  Inherently, small 
satellites are limited in surface area, volume, and mass allocation; driving competition between their need for power 
and robust communications with the requirements of the science or engineering payload they are developed to fly.  
LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope – greatly 
enhancing power generation and communications capabilities of small spacecraft and CubeSats.  The problem is that 
these CubeSats can usually only generate between 7W and 50W of power.  The power that can be generated by the 
LISA-T ranges from tens of watts to several hundred watts, at a much higher mass and stowage efficiency.  A matrix 
of options are in development, including planar (pointed) and omnidirectional (non-pointed) arrays. The former is 
seeking the highest performance possible while the latter is seeking GN&C simplicity. Options for leveraging both 
high performance, ‘typical cost’ triple junction thin-film solar cells as well as moderate performance, low cost cells 
are being developed. Alongside, UHF (ultrahigh frequency), S-band, and X-band antennas are being integrated into 
the array to move their space claim away from the spacecraft and open the door for more capable multi-element antenna 
designs such as those needed for spherical coverage and electronically steered phase arrays. 
Keywords: Solar Array, Antenna, Deployable Structures, CubeSat 
Acronyms/Abbreviations 
Beginning of Life (BOL) 
Early Career Initiative (ECI) 
End of Life (EOL) 
Inflatable Torus Solar Array Technology (ITSAT) 
Low Earth Orbit (LEO) 
Lightweight Integrated Solar Array and anTenna 
Marshall Space Flight Center (MSFC) 
National Aeronautics and Space Administration 
(NASA) 
Space Technology Mission Directorate (STMD) 
Technology Readiness Level (TRL) 
Ultra High Frequency (UHF) 
1. Deployable Power Systems
Using thin-film based solar arrays for spacecraft
applications is not a new idea. [1]. Only recently, 
however, has the technology matured to the point to make 
it feasible. Today’s thin film materials yield a mass 
savings, leading to lighter power system mass and 
increased payload capability. Of interest to small 
spacecraft is their mechanical flexibility, which allows 
the use of innovative stowage and deployment methods.  
Increased packing efficiency improves the specific 
power (W/kg) as well as stowed power density (W/m3), 
enabling higher power generation for small spacecraft. 
Advances in the terrestrial thin-film solar arrays have 
been dramatic.  Several large-scale thin-film or partial 
thin-film arrays are in development, [2-4] though sub-
kilowatt thin-film arrays remain scarce. The Lightweight 
Integrated Solar Array and anTenna (LISA-T) will meet 
this niche power need, both increasing as well as 
simplifying small spacecraft power generation.  
LISA-T builds upon recent advances in solar sail 
propulsion for small spacecraft and the terrestrial 
photovoltaics community to create a combined thin-film 
array and antenna system. The technology is an evolution 
of previously described deployable power systems such 
https://ntrs.nasa.gov/search.jsp?R=20170009097 2019-08-31T01:57:00+00:00Z
IAC-17-C3.4.1 Page 2 of 4 
as the PowerSphere, [5] Inflatable Torus Solar Array 
Technology (ITSAT), [6] and others [7,8]. Fig. 1 shows 
a conceptual rendering of the LISA-T stowed (a) and 
deployed in the omnidirectional (b) and planar (c) 
configurations.   
Fig. 1. Concept drawing of the LISA-T arrays (a) before 
deployment and after; (b) omnidirectional deployed and 
(c) planar deployed.
LISA-T embodies two separate configurations based 
on >99% common components: (i) the omnidirectional 
(non-pointed) and (ii) the planar (pointed). The 
omnidirectional array configuration stows into a 1U 
CubeSat (10 cm x 10 cm x 10 cm ‘unit, or U), while the 
planar array configuration stows into 1/2U. The 
omnidirectional array is three-dimensional; no matter 
how the spacecraft is orientated, power will be generated. 
Primarily for cost-conscious users, the omnidirectional 
system greatly simplifies the spacecraft’s attitude 
determination and control system requirements and is 
generally lower in cost.  
The omnidirectional configuration can provide up to 
125W at BOL. The planar array more of a traditional flat 
configuration. Though it requires the spacecraft to point 
it toward the sun, the planar array maximizes the number 
of solar cell actively generating power, increasing 
dramatically the available power – up to 300W BOL. 
Both a high performance (~28% efficient @ ~$250/W) 
triple junction thin-film solar cell as well as a low cost 
(~10% efficient @ ~$15/W) single junction may be used 
in either configuration, depending upon the needs of the 
user. Stowage efficiencies of nearly 400kW/m3 with 
specific powers of 250W/kg are currently achievable.  A 
comparison to various state-of-the-art power systems can 
be found in Table 1. 
Table 1.  Comparison of LISA-T performance metrics to 
other state-of-the-art spacecraft solar power systems. 
Axes BOL 
Power 
(W) 
Stowed 
Power 
(kW/m3) 
Specific 
Power 
(W/kg) 
Clyde 
Space 3U 
Body 
2 7.3 ~33 ~53 
MMA 
HaWK 
1 36 ~99 ~130 
Clyde 
Space 3U 
Deployable 
1 29 ~54 
Tethers 
Unlimited 
SunMill 
1 80 ~83 ~53 
Pumpkin 
Turkey Tail 
1 56 ~142 ~89 
LISA-T 
Pointed 
1 >225 >400 >300
LISA-T 
Omni 
3 >100 >100 >75
Note: The LISA-T calculations assume a high 
efficiency >25% thin film cell; lower cost cells can 
also be used to generate >100W in the pointed and 
>50W in the omnidirectional configuration. Power
levels are scalable.
Both configurations have been tested through 
Technology Readiness Level (TRL) 6 at the NASA 
George C. Marshall Space Flight Center.  Ambient and 
thermal vacuum stowage and deployments tests have 
been conducted on both configurations and elements 
thereof.  Fig. 2 shows the TRL5 omnidirectional 
prototype: a 60W array based on the low cost cell option. 
Further details on the array architecture and its evolution 
are published elsewhere. [9] 
Fig. 2 The LISA-T arrays deployed in the 
omnidirectional configuration in TRL-5 testing. 
IAC-17-C3.4.1 Page 3 of 4 
2. Deployable Antennas
Non-pointed missions benefit from antenna system
designs with customizable radiation patterns.  Antenna
arrays provide opportunities for custom radiation
patterns, overall gain increases, multiband
communication, directional interference cancelling or
steering, and incoming signal direction determination.
The created surface area of these deployable propulsion
and power systems creates new opportunities for the
inclusion and positioning of multiple lightweight
deployable antennas.
LISA-T integrates lightweight axial mode helical and/or
patch antennas into the deployable system. These
lightweight antennas are compact for stowage and can be
positioned on either the center support of a panel package
(blue lines) or on the panels themselves (red lines) as
shown in Fig. 3.  Antennas on the panels can be placed
on either side of the panel as desired.
Fig. 3.  Antennas can be integrated into either the LISA-
T omnidirectional (top) or planar (bottom) 
configurations. 
Custom lightweight helical and patch antennas have 
been created for S band and X band communications. 
Simulations show both S band and X band helical 
antennas to have a main beam gain greater than 10dbi.  
Simulations show custom patch antennas have a main 
beam gain around 7 dbi.  Both helical and patch antennas 
have significantly less stowed thickness, volume, and 
mass than current state of the art.  By placing multiple 
antennas in various positions on the structure, desired 
coverage patterns or phased array implementations can 
be achieved.   
In addition to S and X bands, integrated UHF dipole 
antennas with a simulated gain of 1dbi have also been 
developed.  These dipole antennas can be integrated into 
the panel between or beside solar cell elements.  Further 
details on the antenna development are published 
elsewhere. [9] 
3. Flight Demonstration
NASA is studying a potential Earth-orbital flight
demonstration of the LISA-T in 2019 or 2020.  The demo 
would consist of a CubeSat Class 1U power and antenna 
module attached to a 6U spacecraft bus.  The current plan 
would have an 180W planar array built from both low 
cost and high performance solar cell packed in the 1U 
power module and deployed once the CubeSat is in low 
Earth orbit. An artist concept of the deployed LISA-T 
system in flight can be seen in Fig. 4.  Because >99% of 
the hardware is shared between the planar and 
omnidirectional configurations, this demonstration will 
also show feasibility for the non-pointed, omnidirectional 
array. Both S- and X-band helical antennas will be 
integrated. The LISA-T antenna structure would 
demonstrate a deployable, multiple band system with low 
mass and volume. The demonstration will show 
feasibility for both high power and spherical coverage 
communications. It should be noted that several 
companies have expressed interest in the capabilities to 
be provided by LISA-T and NASA is currently 
negotiating a licensing agreement with one.   
Fig. 4.  The planar LISA-T configuration is shown 
deployed from a 6U CubeSat during flight. 
4. Conclusions
Deployable structures for spacecraft is not a new
idea.  The technology to finally enable manufacturing, 
packaging and deploying them from very small 
spacecraft, including CubeSats, is finally mature.  
Innovative, multi-functional deployables may provide 
propulsion, power and communication, greatly 
increasing the capability of CubeSats for science and 
exploration and potentially enabling an entirely new 
class of deep space exploration and science missions..  
IAC-17-C3.4.1 Page 4 of 4 
Acknowledgements  
The authors thank the NASA MSFC Advanced 
Concepts Office for their work in performing the 
concept studies for the LISA-T project.   
The LISA-T project is supported through a NASA 
space technology development activity called the Early 
Career Initiative (ECI), sponsored by the Space 
Technology Mission Directorate (STMD). LISA-T is 
being completed in partnership with ManTech\NeXolve 
(Huntsville, Al) and is managed under NASA’s Early 
Stage Portfolio.  
References 
[1]S. Bailey, and R. Raffaelle, Space solar cells and
arrays, Handbook of Photovoltaic Science and
Engineering, 2003, pp. 413-448.
[2]B. Rory et al., Development of a passively deployed
roll-out solar array, 2006.
[3] B. Spence et al., Next generation ultraflex solar array
for NASA's New Millennium Program Space
Technology 8, IEEE, 2005, pp. 824-836.
[4] D. Manzella and K. Hack, High-Power Solar Electric
Propulsion for Future NASA Missions, 2014.
[5] E.J. Simburger et al., Thin-film technology
development for the PowerSphere, Materials Science
and Engineering: B, 2005, 116, (3), pp. 265-272.
[6] P. Malone, L. Crawford, and G. Williams,
Developing an inflatable solar array, 1993.
[7] M.L. Breen et al., IBIS (Integrated
Blanket/Interconnect System), Boeing's solution for
implementing IMM (Inverted Metamorphic) solar
cells on a light-weight flexible solar panel, in Editor
IBIS (Integrated Blanket/Interconnect System),
Boeing's solution for implementing IMM (Inverted
Metamorphic) solar cells on a light-weight flexible
solar panel, IEEE, 2010, edn., pp. 000723-000724.
[8] J.W. Zuckermandel, S. Enger, and N. Gupta, Design,
build, and testing of TacSat thin film solar arrays, in
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[9] Lockett, Tiffany Russell, et al. "Advancements of the
Lightweight Integrated Solar Array and Transceiver
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