Innovative Uses for TDRSS The South Pole TDRSS

Innovative Uses for TDRSS: The South Pole TDRSS Relay (SPTR) Technology Forum February 17, 1998 Dave Israel Code 567. 3

SPTR Overview • The South Pole TDRSS Relay was installed in December 1997. • It was funded as a Proof of Concept to prove the following: – TDRS-1 can support the South Pole – TDRSS can provide a high speed IP connection – TDRSS can provide a high speed file transfer capability 2

TDRS-1 Visibility from the South Pole • TDRS-1’s high inclination (>9. 5 degrees) makes the satellite in view of the South Pole for over 3. 5 hours. • This time period will increase over time. • TDRSS capabilities are much greater than the capabilities of any other satellites visible from the South Pole. 3

SPTR Design Goals • • Demonstrate 50 Mbps return link Install a 2 - 10 Mbps file transfer capability Install an 1. 024 Mbps bi-directional IP link Prove operations in South Pole environment 4

SPTR Results • 50 Mbps KSAR from the Pole was successfully tested in December. • S-Band IP and K-Band File Transfer services were declared operational on 1/5/98. • Since 1/6/98 – 592 Mbytes on S-Band to the Pole – 442 Mbytes on S-Band from the Pole – 17 Gbytes on K-Band from the Pole 5

What’s Innovative about SPTR? • First time true IP data was transferred by TDRSS to/from the Internet. • First time users were able to FTP their data from WSC • User RF and data system almost entirely COTS 6

SPTR IP Connection

SPTR File Transfer Service

SPTR Additions to White Sands 9

SPTR Additions to White Sands (cont’d) • • New Internet connection into WSC (~1 Mbps) File Server for K-Band transfers & FTP Router connects local LAN to Internet and TDRSS link TDRSS Data Interface provides coding, scrambling, and de -scrambling • Duplicate equipment at both White Sands Terminals 10

SPTR South Pole Hardware 11

SPTR South Pole Hardware (cont’d) • K-Band System – – – • File Server Convolutional Encoder BPSK Modulator 20 W TWT 4 foot antenna S-Band System – – – Router Satellite Modem Up/Downconverter 10 W PA 4 foot antenna 12

SPTR South Pole Hardware (cont’d) 13

Advantages of Direct IP TDRSS Link • No additional data lines required - access through the Internet • Any IP software can be used • Make full use of commercial standards and new developments 14

Disadvantages of Direct IP Link • • Two-way connection required Geosat delay effects Data performance better than 1 e-5 BER required Access through the Internet 15

Possible Future Users • • Remote Field Camps (Aruba Eclipse support, Antarctica) Balloons Planes University Explorers 16

Aruba Eclipse Support • Full solar eclipse February 26, 1998 • NASA support requested by the Exploratorium for Internet connectivity to Aruba for eclipse broadcast • Only changes required at WSC are router updates • Functional duplicate of SPTR S-band system put together for the Aruba side of the link 17

Eclipse Support Hardware (Field Camp Scenario) 18

Potential Follow-On Activities • Assemble a permanent “Field Camp” rack • Experiment with methods to optimize TCP/IP performance • Minimize user system size/power for remote operations and possible flight 19

Summary • The basic infrastructure is now in WSC which will allow future tests and missions to use the Internet and Internet standards for data handling and transmissions. • We’re looking for users/experimenters • More information – http: //www 530. gsfc. nasa. gov/SPTR/ – http: //www. exploratorium. edu/eclipse – e-mail: dave. israel@gsfc. nasa. gov 20