36:
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119:) in the early 1960s. Consisting of parabolic dish antennas and telephone switching equipment deployed around the world, the STADAN provided space-to-ground communications for approximately 15 minutes of a 90-minute orbit period. This limited contact-period sufficed for uncrewed spacecraft, but crewed spacecraft require a much higher data collection time.
347:
satellites. Three SGLTs are located at STGT, but only two are located at WSGT. The system architects moved the remaining SGLT to Guam to provide full network support for the satellite covering the ZOE. Considered a remote part of the WSGT, the distance and location of the SGLT is transparent to network users.
619:
Note: while a TDRSS satellite is in the manufacturing process it is given a letter designation, but once it has successfully achieved the correct geosynchronous orbit it is referred to with a number (for example, TDRS-A during development and before on-orbit acceptance, and TDRS-1 after acceptance on
422:
The MOC is the focal point of spacecraft operations. It will schedule requests for support, monitor spacecraft performance and upload control information to the spacecraft (through TDRSS). MOC consists of principal investigators, mission planners and flight operators. Principal investigators initiate
149:
Even after consolidation, STDN had some drawbacks. Since the entire network consisted of ground stations spread around the globe, these sites were vulnerable to the political whims of the host country. In order to maintain a high-reliability rate coupled with higher data transfer speeds, NASA began a
405:
NISN provides the data transfer backbone for space missions. It is a cost-effect wide area network telecommunications service for transmission of data, video, and voice for all NASA enterprises, programs and centers. This part of the STDN consists of infrastructure and computers dedicated to monitor
330:
that is for facility staff only. NASA decided on the location of the ground terminals using very specific criteria. Foremost was the ground station's view of the satellites; the location had to be close enough to the equator to view the skies, both east and west. Weather was another important factor
426:
The MMFD lab provides flight project and tracking network support. Flight project support consists of orbital and attitude determination and control. Orbital parameters are traced through the actual orbit of the mission spacecraft and compared to its predicted orbit. Attitude determination computes
418:
The NCC provides service planning, control, assurance and accountability. Service planning takes user requests and disseminates the information to the appropriate SN elements. Service control and assurance supports functions of real-time usage, such as receipt, validation, display and dissemination
334:
WSGT went online with the 1983 launch of TDRS-A by the Space
Shuttle Challenger. STGT became operational in 1994, completing the system after Flight-6's on-orbit checkout earlier in the year. Additionally, after completion of the second terminal, NASA held a contest to name the two stations. Local
521:
Almost twenty years later, on
November 23, 2007, an on-line trade publication noted, "While NASA uses the (TDRSS) satellites to communicate with the space shuttle and international space station, most of their bandwidth is devoted to the Pentagon, which covers the lion's share of TDRSS operations
193:
TDRSS is similar to most other space systems, whereby it is composed of three segments: the ground, space and user segments. These three segments work in conjunction to accomplish the mission. An emergency or failure in any one segment could have catastrophic impact on the rest of the system. For
165:
After the study was completed, NASA realized that a minor system modification was needed to achieve 100% global coverage. A small area would not be within line-of-sight of any satellites – a so-called Zone of
Exclusion (ZOE). With the ZOE, neither TDRS satellite could contact a spacecraft under a
67:
for space communications. The system was designed to replace an existing network of ground stations that had supported all of NASA's crewed flight missions. The prime design goal was to increase the time spacecraft were in communication with the ground and improve the amount of data that could be
153:
The space segment of the new system would rely upon satellites in geostationary orbit. These satellites, by virtue of their position, could transmit and receive data to lower orbiting satellites and still stay within sight of the ground station. The operational TDRSS constellation would use two
443:
The space segment of the TDRSS constellation is the most dynamic part of the system. Even with nine satellites on orbit, the system provides support with three primary satellites, while using the rest as on-orbit spares capable of immediate usage as primaries. The original TDRSS design had two
346:
WSGT and STGT are geographically separated and completely independent of one another, while retaining a backup fiber-optic link to transfer data between sites in case of emergency. Each ground station has 19-meter dishes, known as Space-Ground Link
Terminals (SGLT), to communicate with the
473:
relay their observations to their respective mission control centers through TDRSS. Since crewed space flight was one of the primary reasons for building TDRSS, the space shuttle and
International Space Station voice communications are routed through the system.
184:
As of July 2009, TDRS project manager is Jeff J. Gramling, NASA Goddard Space Flight Center. Robert P. Buchanan, Deputy
Project Manager, retired after 41 years at NASA with TDRS as one of final missions. Boeing is responsible for the construction of TDRS K.
166:
certain altitude (646 nautical miles). With the addition of another satellite to cover the ZOE and ground station nearby, 100% coverage could exist. The space-based network study created a system that became the plan for the present-day TDRSS network design.
141:
in the mid-1970s, a requirement for a higher performance space-based communication system arose. At the end of the Apollo program, NASA realized that MSFN and STADAN had evolved to have similar capabilities and decided to merge the two networks to create the
419:
of TDRSS performance data. Service accountability provides accounting reports on the use of the NCC and network resources. The NCC was originally located at
Goddard Space-flight Center, in Greenbelt, Maryland until 2000, when it was relocated to the WSC.
381:
is an extension of the WSGT. The terminal contains SGLT 6, with the
Communication Service Controller (CSC) located at STGT's TDRS Operations Control Center (TOCC). Before the GRGT was operational, an auxiliary system was located at
406:
network traffic flow, such as fiber optic links, routers and switches. Data can flow through NISN two ways: using the
Internet Protocol Operational Network (IPONET) or the High Data Rate System (HDRS). IPONET uses the
427:
sets of parameters that describe a spacecraft's orientation relative to known objects (Sun, Moon, stars or Earth's magnetic field). Tracking network support analyzes and evaluates the quality of the tracking data.
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and one on-orbit spare. The surge in user requirements during the 1980s allowed NASA to expand the network with the addition of more satellites, with some being co-located in a particularly busy orbital slot. See
423:
requests for SN support. Mission planners provide documentation for the spacecraft and its mission. And flight operators are the final link, sending commands to the spacecraft and performing the operations.
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to 48 Mbit/s, for specialized missions requiring a high rate of data transfer. HDRS does not require the infrastructure of routers, switches and gateways to send its data forward like IPONET.
238:. These three stations are the heart of the network, providing command & control services. Under a system upgrade that has been completed, a new terminal has been built at Blossom Point, Maryland.
828:
525:
In
October 2008, the NRO declassified the existence of mission ground stations in the US called Aerospace Data Facility (ADF)- Colorado, ADF-East and ADF-Southwest near
402:(NISN), network control center (NCC), mission operations center (MOC), spacecraft data processing facility (SDPF), and the multi mission flight dynamics lab (MMFD).
177:(ACTS) programs prototyped many of the technologies used on TDRSS and other commercial communications satellites, including frequency division multiple-access (
759:
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protocol common to all computers connected to the Internet, and is a standard way to ship data. The High Data Rate System transports data rates from 2
223:
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orbit and put into operational use). Thus, satellites that are lost in launch failures or have massive malfunctions are never numbered (for example,
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112:
947:
Consolidated Space Operations Contract (CSOC). (2000) Certification & Training Course 880 & 882: TDRSS Orientation & System Data Flow.
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881:
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285:
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for STGT. These names seem to have been for publicity purposes only, for official NASA documentation use WSGT and STGT or WSC as designators.
174:
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712:
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Wertz, J. & Larson, W. (1999) Space Mission Analysis and Design, Third Edition. Torrance, California: Microcosm Press.
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To satisfy the requirement for long-duration, highly available space-to-ground communications, NASA created the
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Sellers, J. (2000) Understanding Space: An Introduction to Astronautics. New York: McGraw-Hill Companies, Inc.
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745:
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The TDRSS system has been used to provide data relay services to many orbiting observatories, and also to
944:
Baker, D. (Ed.) (2001) Jane's Space Directory: 2001–2002. Alexandria, Virginia: Jane's Information Group.
896:
700:
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331:– New Mexico has, on average, almost 350 days of sunshine per year, with a very low precipitation level.
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As early as 1989, it was reported that an important function of TDRSS was to provide data relay for the
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use TDRSS for data relay. TDRSS is also used to provide launch data relay for expendable boosters.
56:
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The most recent generation of satellites provides ground reception rates of 6 Mbit/s in the
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Thompson, T. (1996) TRW Space Log. Redondo Beach, California: TRW Space & Electronics Group.
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The user segment of TDRSS includes many of NASA's most prominent programs. Programs such as the
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https://web.archive.org/web/20050126202052/http://nmsp.gsfc.nasa.gov/TUBE/pdf/infopack.pdf
130:(DSN), interacted with crewed spacecraft higher than 10,000 miles from Earth, such as the
80:, a two-stage solid rocket booster developed for the shuttle. Other TDRS were launched by
8:
235:
181:), three-axis spacecraft stabilization and high-performance communications technologies.
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missions, in addition to its primary mission of data collection from deep space probes.
1000:
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127:
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NASA. (1996) 2nd TDRSS Workshop: 25–26 Jun 1996. Retrieved from Internet 25 Aug 2003.
122:
A side-by-side network established right after STADAN in the early 1960s, called the
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https://web.archive.org/web/20050214060604/http://nmsp.gsfc.nasa.gov/tdrss/guam.html
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costs and is driving many of the system's requirements, some of them classified."
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NASA. (2000) Guam Remote Ground Terminal. Retrieved from Internet 25 Aug 2003.
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126:(MSFN), interacted with crewed spacecraft in Earth orbit. Another network, the
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Kraft, C. (2002) Flight: My Life in Mission Control. New York: Plume Books.
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Space.com: Replacement Satellites Top the List of Upcoming Nasa Deals
537:, respectively. ADF-Colorado and ADF-East are known to be located at
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746:"NASA Tracking and Data Relay Satellite Mission Passes Major Review"
19:
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by way of the TDRSS South Pole Relay. The US-built sections of the
202:
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study to augment the system with space-based communication nodes.
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NASA's Goddard Space Flight Center TDRS K/L Project Official Page
786:"NASA Space Network to Begin New Design Phase For Ground Segment"
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Kranz, G. (2000) Failure is Not an Option. New York: Plume Books
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NASA's Goddard Space Flight Center Space Network Official Page
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middle school students chose Cacique (kah-see-keh), meaning
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https://certifiedpedia.com/tracking-fox-gps-tracker-review/
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of TDRSS consists of three ground stations located at the
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Declassified Information from the NRO: accessed 01/05/11
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radar imaging reconnaissance satellites operated by the
194:
this reason all segments have redundancy factored in.
103:. This is mainly used by the United States military.
639:
319:
Additionally, the WSC remotely controls the GRGT on
557:The first seven TDRSS satellites were built by the
624:, which was never numbered due to its loss in the
549:, assumed to be at the White Sands TDRSS station.
224:Naval Computer and Telecommunications Station Guam
808:"NASA Awards Space Network Expansion-East Option"
55:, pronounced "T-driss") is a network of American
1168:
113:Spacecraft Tracking and Data Acquisition Network
389:
72:were launched in the 1980s and 1990s with the
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589:The TDRSS system is briefly mentioned in the
16:Network of American communications satellites
175:Advanced Communications Technology Satellite
701:NASA Space Science Data Coordinated Archive
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599:. It is also brought up in the 1997 movie
569:, and all of the satellites since then by
821:
665: – Planned communications satellites
1017:Tracking and Data Relay Satellite System
760:"Generation to Generation, A Lower Risk"
505:
481:
444:primary satellites, designated TDE, for
434:
201:
154:satellites, designated TDE and TDW (for
49:Tracking and Data Relay Satellite System
34:
26:
18:
1177:Communications satellite constellations
868:Mission Ground Station Declassification
350:The Guam Remote Ground Terminal (GRGT)
1169:
584:
396:Space Flight Tracking and Data Network
989:
571:Hughes Space and Communications, Inc.
829:"Spy Satellites: Entering a New Era"
457:for more details on the satellites.
315:Extended TDRS Ground Terminal (ETGT)
282:Second TDRSS Ground Terminal (STGT)
144:Spacecraft Tracking and Data Network
63:, TDRS) and ground stations used by
249:White Sands Ground Terminal (WSGT)
13:
1187:Communications satellite operators
928:NASA's TDRSS program overview page
663:Indian Data Relay Satellite System
218:(WSC) in southern New Mexico, the
70:Tracking and Data Relay Satellites
39:An unflown TDRS on display at the
14:
1198:
1182:Tracking and Data Relay Satellite
1028:Tracking and data relay satellite
916:
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500:International Space Station (ISS)
455:Tracking and Data Relay Satellite
222:Remote Ground Terminal (GRGT) at
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61:tracking and data relay satellite
31:Location of TDRS as of March 2019
1089:
897:Area58 Blog: Capt. K Panzenhagen
642:
430:
400:NASA Integrated Services Network
171:Application Technology Satellite
901:
890:
872:
744:Susan Hendrix (July 22, 2009).
460:
339:for WSGT, and Danzante meaning
879:Buckley AFB: Tenants Factsheet
861:
850:
800:
778:
752:
737:
705:
694:
545:; ADF-Southwest is located at
516:National Reconnaissance Office
326:The WSC has its own exit from
188:
169:As early as the 1960s, NASA's
1:
687:
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477:
7:
683:– Chinese data relay system
671:– Russian data relay system
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486:South Pole Tracking Relay-2
390:Incorporation into the STDN
232:Goddard Space Flight Center
206:Guam Remote Ground Terminal
162:), and one on-orbit spare.
124:Manned Space Flight Network
95:and 800 Mbit/s in the
41:Steven F. Udvar-Hazy Center
10:
1203:
962:Tracking Fox GPS Tracker.
658:European Data Relay System
612:
106:
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567:Redondo Beach, California
561:corporation (now part of
547:White Sands Missile Range
137:With the creation of the
57:communications satellites
938:
1157:denotes launch failure.
1033:List of TDRS satellites
615:List of TDRS satellites
394:The major parts of the
43:in Chantilly, Virginia.
575:El Segundo, California
565:Aerospace Systems) in
543:Fort Belvoir, Virginia
535:Las Cruces, New Mexico
487:
467:Hubble Space Telescope
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228:Network Control Center
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32:
24:
675:Satellite Data System
577:, (now a part of the
506:Military applications
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38:
30:
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713:"TDRSS 2nd Workshop"
369:13.6148°N 144.8565°E
301:32.5430°N 106.6120°W
268:32.5007°N 106.6086°W
78:Inertial Upper Stage
76:and made use of the
585:Cultural references
494:facilities such as
365: /
297: /
264: /
236:Greenbelt, Maryland
216:White Sands Complex
884:2015-09-27 at the
650:Spaceflight portal
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306:32.5430; -106.6120
273:32.5007; -106.6086
241:WSC, located near
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128:Deep Space Network
68:transferred. Many
45:
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25:
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1099:Second generation
374:13.6148; 144.8565
23:TDRS Program Logo
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1125:Third generation
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762:. Archived from
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718:. Archived from
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393:
384:Diego Garcia
349:
345:
340:
336:
333:
325:
318:
240:
209:
192:
183:
168:
164:
159:
155:
152:
148:
136:
121:
110:
90:
52:
48:
46:
813:October 25,
792:October 25,
539:Buckley AFB
372: /
360:144°51′23″E
304: /
292:106°36′43″W
271: /
259:106°36′31″W
230:located at
189:The network
1171:Categories
688:References
628:Challenger
613:See also:
591:James Bond
553:Production
541:, CO and
478:Operations
357:13°36′53″N
289:32°32′35″N
256:32°30′03″N
243:Las Cruces
173:(ATS) and
596:Moonraker
492:Antarctic
88:rockets.
82:Atlas IIa
47:The U.S.
882:Archived
681:Tianlian
636:See also
630:disaster
512:Lacrosse
146:(STDN).
101:Ka-bands
1155:Italics
1142:TDRS-13
1137:TDRS-12
1132:TDRS-11
1116:TDRS-10
842:20 July
836:Science
593:movie,
471:LANDSAT
107:Origins
86:Atlas V
1111:TDRS-9
1106:TDRS-8
1081:TDRS-7
1076:TDRS-6
1071:TDRS-5
1066:TDRS-4
1061:TDRS-3
1055:TDRS-B
1049:TDRS-1
622:TDRS-B
579:Boeing
533:, and
412:Mbit/s
408:TCP/IP
341:dancer
337:leader
226:, and
132:Apollo
117:STADAN
93:S-band
939:Notes
832:(PDF)
723:(PDF)
716:(PDF)
573:, in
53:TDRSS
844:2013
815:2012
794:2012
772:2010
731:2010
469:and
450:west
446:east
321:Guam
220:Guam
210:The
179:FDMA
160:west
158:and
156:east
99:and
84:and
65:NASA
632:).
559:TRW
234:in
97:Ku-
1173::
834:.
605:.
529:,
518:.
386:.
323:.
1009:e
1002:t
995:v
846:.
817:.
796:.
774:.
748:.
733:.
115:(
51:(
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