COMBINING LASER COMMUNICATIONS AND POWER BEAMING FOR USE ON PLANETARY PROBESLiz Hyde

San Jose State University

Agenda• Introduction

• Current issues for Planetary Probes: Communications and Power• Solutions: Laser Communications and Power Beaming

• Improvements• Combine two units into one!

• Proving the Technology• CubeSat-based Technology Demonstration Mission

• Conclusions

Introduction: Current Issues

Communications

• Increased data package size requires improvements in data rate

• Alternative communication methods desired as to not congest RF bands

Power

• New developments in sensor technology increase the need of high-voltage power• Solar power is unreliable at

distances >1.5 AU

• Valuable data can be lost while probes are in eclipse

SOLUTIONS

Solution: Power and Comms Waystation

A Solution: Laser Communications• Laser Communications can increase data rate 100-1,000x

that of traditional RF radios.• Technology has been tested in space (LRO, LADEE

[2013])• Technology also being used on the ground for military

applications (Ship-to-Ship, UAV-to-Ground)

Laser Comms: How it Works

100101100101010

Digital Data Laser PhotovoltaicCells

Decoder

*Think of Morse Code, transmitted by laser!

A Solution: Laser Power Beaming• Wireless power transfer idea has been around since

1950’s• Technology also applies to Space-to-Ground and Ground-

to-Space applications• Space-to-Space demonstration in 2005 (JAXA/ESA)

Laser Power Beaming: How it Works

Bonus Improvement: Integrate Comms and Power Systems• Laser Communications and Laser Power have one big

thing in common: the Laser!• A laser suited for Communications would also be suited

for Power Beaming• Using one laser for multiple purposes saves on mass and

volume.

TECHNOLOGY DEMONSTRATION

How To Demonstrate the Technology?CubeSats!

• CubeSats have been used to for low-cost, fast-schedule technology demonstration missions

• Using heritage equipment focuses development on payloads

Demo Mission: The Satellites

Pitcher

• Payload contains the Laser that will transmit both data and electrical power

• Avionics based off of previously flown designs (TechEdSat)

• Data is pre-loaded packets consisting of sample images (high-res images, sensor data, etc)

Catcher

• Payload consists of a deployable “target” photovoltaic array• Included is the data and

power decoding unit

• Avionics based off of previously flown designs (TechEdSat)

• Data transmitted to the ground using traditional RF means

Demo Mission: The Satellites

Pitcher Catcher

Demo Mission: The Satellites

Pitcher Catcher

CONCLUSIONS

Conclusions• Both Laser Communications and Laser Power Beaming

provide benefits for space probes• An added benefit to these technologies is the ability to

have one unit preforming multiple tasks• Testing this technology with CubeSats may pave the way

to larger usage of the technology

Acknowledgements • Dr. Periklis Papadopolus

• San Jose State University

• James Grady• Global Enterprise Initiative Inc.

• Marcus Murbach• NASA Ames Research Center

QUESTIONS?Thanks for your interest!

Liz.L.Hyde@gmail.com

BACK-UP SLIDES

End to End Efficiancy

Aiming Error

Beam Diameter = 1.5mTarget Panel Area = 0.3 x 0.3 m

Beam Divergance

ϑ

L

dbeam

ϑ = Divergence angledbeam = Diameter of beam at the targetL = Separation distance

dbeam=2Ltan(ϑ/2)