For other uses, see Oscar. OSCAR is an acronym for Orbital Satellite Carrying Amateur Radio.
OSCAR series satellites use amateur radio frequencies to communicate with earth. They are conceived, designed, and built by amateur radio operators under the general direction of national organisations such as AMSAT.
The beginning
The first amateur satellite simply named OSCAR-1 , was launched on December 12, 1961, barely four years after the launch of Russia's first satellite, Sputnik. OSCAR-1 was the very first satellite to be ejected as a secondary payload and subsequently enter a separate orbit. Despite being in orbit only 22 days OSCAR-1 was an immediate success with over 570 amateur radio operators in 28 countries forwarding observations to Project OSCAR. Throughout the years OSCAR satellites have helped make significant breakthroughs in the science of satellite communications. A few advancements include the launch of the very first satellite voice transponders and the development of highly advanced digital "store-and-forward" messaging transponder techniques. To-date over 70 OSCAR's have been launched with more to be launched in the near future.
OSCAR Satellite Communications
Currently OSCAR satellites support many different types of operation including FM voice, SSB voice, as well as digital communications of AX.25 FSK (Packet radio) and PSK-31.
Mode Designators
- Historically OSCAR uplink (transmit to) and downlink (receive from) frequencies were designated using single letter codes.
-
- New uplink and downlink designations use sets of paired letters following the structure X/Y where X is the uplink band and Y is the downlink band.
-
-
Doppler shift
Due to the high orbital speed of OSCAR satellites, the uplink and downlink frequencies will vary during the course of a satellite pass. This phenomenon is known as the doppler effect. While the satellite is moving towards the ground station, the downlink frequency will appear to be higher than normal and therefore, the receiver frequency at the ground station must be adjusted higher in order to continue receiving the satellite. The satellite in turn, will be receiving the uplink signal at a higher frequency than normal so the ground station's transmitted uplink frequency must be lower in order to be received by the satellite. After the satellite passes overhead and begins to move away, this process reverses itself. The downlink frequency will appear lower and the uplink frequency will need to be adjusted higher. The following mathematical formulas relate the doppler shift to the velocity of the satellite.
| Where: |
| Failed to parse (Missing texvc executable; please see math/README to configure.): f_d |
= |
doppler corrected downlink frequency |
| Failed to parse (Missing texvc executable; please see math/README to configure.): f_u |
= |
doppler corrected uplink frequency |
| Failed to parse (Missing texvc executable; please see math/README to configure.): f |
= |
original frequency |
| Failed to parse (Missing texvc executable; please see math/README to configure.): v |
= |
velocity of the satellite relative to ground station in meters/second.
Positive when moving towards, negative when moving away. |
| Failed to parse (Missing texvc executable; please see math/README to configure.): C |
= |
the speed of light in a vacuum (Failed to parse (Missing texvc executable; please see math/README to configure.): 3x10^8
meters/second).
|
| Change in frequency |
Downlink Correction |
Uplink Correction |
|
Failed to parse (Missing texvc executable; please see math/README to configure.): \Delta f=\frac{fv}{C}
|
Failed to parse (Missing texvc executable; please see math/README to configure.): f_d=f+\frac{fv}{C}
|
Failed to parse (Missing texvc executable; please see math/README to configure.): f_u=f-\frac{fv}{C}
|
Due to the complexity of finding the relative velocity of the satellite and the speed with which these corrections must be made, these calculations are normally accomplished using satellite tracking software. Many modern transceivers include a computer interface that allows for automatic doppler correction. Manual doppler correction is possible, however it is difficult to remain exactly on frequency. FM is more tolerant of doppler shift than SSB and therefore much easier to tune manually.
Satellites previously launched
The names of the satellites below are sorted in chronological order by launch date, acsending. The status column denotes the current operational status of the satellite. Green signifies that the satellite is currently operational, orange indicates that the satellite is partially operational or failing. Red indicates that the satellite is non operational and black indicates that the satellite has re-entered the earth's atmosphere. The country listing denotes the country that constructed the satellite and not the launching country.
-
| Name (a.k.a) |
Status |
Launched |
Country |
| OSCAR (OSCAR 1) |
|
1961-12-12 |
USA |
| OSCAR II (OSCAR 2) |
|
1962-06-02 |
USA |
| OSCAR III (OSCAR 3, EGRS-3) |
|
1965-03-09 |
USA |
| OSCAR IV (OSCAR 4) |
|
1965-12-21 |
USA |
| Australis-OSCAR 5 (OSCAR 5, AO-5, AO-A) |
|
1970-01-23 |
Australia |
| AMSAT-OSCAR 6 (OSCAR 6, AO-6, AO-C, P2A) |
|
1972-10-15 |
USA |
| AMSAT-OSCAR 7 (OSCAR 7, AO-7, AO-B, P2B) |
|
1974-11-15 |
USA / Spain |
| AMSAT-OSCAR 8 (OSCAR 8, AO-8, AO-D, P2D) |
|
1978-03-05 |
USA |
| UoSat-OSCAR 9 (UOSAT 1, UO-9) |
|
1981-10-06 |
UK |
| AMSAT-OSCAR 10 (Phase 3B, P3B) |
|
1983-06-16 |
USA |
| UoSat-OSCAR 11 (UoSat-2, UO-11, UoSAT-B) |
|
1984-03-01 |
UK |
| Fuji-OSCAR 12 (JAS 1, FO-12) |
|
1986-08-13 |
Japan |
| AMSAT-OSCAR 13 (Phase 3C, AO-13, P3C) |
|
1988-06-15 |
USA |
| UOSAT-OSCAR 14 (UoSAT-3, UO-14 UoSAT-D) |
|
1990-01-21 |
UK |
| UOSAT-OSCAR 15 (UoSAT-4, UO-15, UoSAT-E) |
|
1990-01-22 |
UK |
| AMSAT-OSCAR 16 (Pacsat, AO-16, Microsat-1) |
|
1990-01-22 |
USA |
| Dove-OSCAR 17 (Dove, DO-17, Microsat-2) |
|
1990-01-22 |
Brazil |
| Weber-OSCAR 18 (WeberSAT, WO-18, Microsat-3) |
|
1990-01-22 |
USA |
| LUSAT-OSCAR 19 (LUSAT, LO-4, Microsat-4) |
|
1990-01-22 |
Argentina |
| Fuji-OSCAR 20 (JAS 1B, FO-20, Fuji-1B) |
|
1990-02-07 |
Japan |
| AMSAT-OSCAR 21 (RS-14, AO-21, Informator-1) |
|
1991-01-29 |
Russia |
| Radio Sputnik 12 |
|
1991-02-05 |
Russia |
| Radio Sputnik 13 |
|
1991-02-05 |
Russia |
| UoSat-OSCAR 22 (UOSAT 5, UO-22 UoSAT-F) |
|
1991-07-17 |
UK |
| KitSAT-OSCAR 23 (KITSAT 1, KO-23, Uribyol-1) |
|
1992-08-10 |
Korea |
| Arasene-OSCAR 24 (Arasene, AO-24) |
|
1993-05-12 |
France |
| AMRAD-OSCAR 27 (EYESAT-1, AO-27) |
|
1993-09-26 |
USA |
| KitSAT-OSCAR 25 (KITSAT B, KO-25, Kitsat-2, Uribyol-2) |
|
1993-09-26 |
Korea |
| POSAT-OSCAR 28 (POSAT, Posat-1) |
|
1993-09-26 |
Portugal |
| Italy-OSCAR 26 (ITAMSAT, IO-26) |
|
1993-09-26 |
Italy |
| Radio Sputnik 15 (RadioSkaf-15, RS-15, Radio-ROSTO) |
|
1994-12-26 |
Russia |
| Fuji-OSCAR 29 (JAS 2, FO-29, Fuji-2) |
|
1996-08-17 |
Japan |
| Mexico-OSCAR 30 (UNAMSAT-2, MO-30, Unamsat-B, Kosmos-2334) |
|
1996-09-05 |
Mexico/Russia |
| Gurwin-OSCAR 32 (GO-32, Gurwin-1b, Techsat-1b) |
|
1998-07-10 |
Israel |
| Thai-Microsatellite-OSCAR 31 (TMSAT-1, TO-31) |
|
1998-07-10 |
Thailand |
| SEDSat-OSCAR 33 (SEDSat, SO-33, SEDsat-1) |
|
1998-10-24 |
USA |
| Pansat-OSCAR 34 (PAN SAT, PO-34) |
|
1998-10-30 |
USA |
| ARISS (ARISS) |
|
|
International |
| ASU-OSCAR 37 (AO-37, ASUsat-1, ASUSAT) |
|
2000-01-27 |
USA |
| OPAL-OSCAR 38 (OO-38, StenSat, OPAL) |
|
2000-01-27 |
USA |
| Weber-OSCAR 39 (WO-39, JAWSAT) |
|
2000-01-27 |
USA |
| Saudi-OSCAR 41 (SO-41, Saudisat 1A) |
|
2000-01-27 |
Saudi Arabia |
| Malaysian-OSCAR 46 (MO-46, TIUNGSAT-1) |
|
2000-09-26 |
Malaysia |
| Saudi-OSCAR 42 (SO-42, Saudisat 1B) |
|
2000-09-26 |
Saudi Arabia |
| AMSAT-OSCAR 40 (AO-40, Phase 3D, P3D) |
|
2000-11-16 |
USA |
| Navy-OSCAR 44 (NO-44, PCSat) |
|
2001-09-30 |
USA |
| Starshine-OSCAR 43 (SO-43, Starshine 3) |
|
2001-09-30 |
USA |
| Navy-OSCAR 45 (NO-45, Sapphire) |
|
2001-09-30 |
USA |
| BreizhSAT-OSCAR 47 (BO-47, IDEFIX CU1) |
|
2002-05-04 |
France |
| BreizhSAT-OSCAR 48 (BO-48, IDEFIX CU2) |
|
2002-05-04 |
France |
| Saudi-OSCAR 50 (SO-50, Saudisat-1C) |
|
2002-12-20 |
Saudi Arabia |
| AATiS-OSCAR 49 (AO-49, Safir-M, RUBIN 2) |
|
2002-12-20 |
Germany |
| CubeSat-OSCAR 55 (Cute-1) |
|
2003-06-30 |
Japan |
| CubeSat-OSCAR 57 (CubeSat-XI-IV) |
|
2003-06-30 |
Japan |
| CanX-1 |
|
2003-06-30 |
Canada |
| DTUSat |
|
2003-06-30 |
Denmark |
| AAU Cubesat |
|
2003-06-30 |
Denmark |
| AMSAT-OSCAR 51 (Echo) |
|
2004-06-28 |
USA |
| RS-22 (Mozhayets 4) |
|
2004-09-27 |
Russia |
| VUSat-OSCAR 52 (Hamsat, VUSat) |
|
2005-05-05 |
India / Netherlands |
| PCSat2 (PCSAT2) |
|
2005-08-03 |
USA |
| AMSAT-OSCAR 54 (AO-54, SuitSat, Radioskaf) |
|
2005-09-08 |
International |
| eXpress-OSCAR 53 (XO-53, SSETI Express) |
|
2005-10-27 |
ESA |
| CubeSat-OSCAR 58 (CO-58, Cubesat XI-V) |
|
2005-10-27 |
Japan |
| UWE-1 |
|
2005-10-27 |
Germany |
| NCube-2 |
|
2005-10-27 |
Norway |
| CubeSat-OSCAR 56 (CO-56, Cute-1.7) |
|
2006-02-21 |
Japan |
| K7RR-Sat |
|
2006-07-26 |
USA |
| CP2 |
|
2006-07-26 |
USA |
| HAUSAT 1 |
|
2006-07-26 |
South Korea |
| ICE Cube 1 |
|
2006-07-26 |
USA |
| ICE Cube 2 |
|
2006-07-26 |
USA |
| ION |
|
2006-07-26 |
USA |
| KUTESat |
|
2006-07-26 |
USA |
| MEROPE |
|
2006-07-26 |
USA |
| nCUBE 1 |
|
2006-07-26 |
| RINCON |
|
2006-07-26 |
USA |
| SACRED |
|
2006-07-26 |
USA |
| SEEDS |
|
2006-07-26 |
Japan |
| Voyager |
|
2006-07-26 |
USA |
| PicPot |
|
2006-07-26 |
Italy |
| Libertad-1 |
|
2006-09-15 |
Colombia |
| CAPE-1 |
|
2006-09-15 |
USA |
| CP3 |
|
2006-09-30 |
USA |
List current as of 2006-10-14
Multinational effort
Currently 21 countries have launched an OSCAR satellite. These countries, in chronological order by date of launch, include: The United Kingdom, The United States of America, Spain, Australia, Japan, Brazil, Argentina, Russia, France, Portugal, Korea, Italy, Mexico, Israel, Thailand, South Africa, Malaysia, Saudi Arabia, Germany, India, & Colombia.
Satellites in development
Trivia
SuitSat, an obsolete Russian space suit with a transmitter aboard, is officially known as OSCAR 54. In a twist of fate, "Oscar" was the name given to an obsolete space suit by its young owner in the book "Have Space Suit, Will Travel," by Robert A Heinlein. This book was originally published a year after the launch of the first artificial satellite (Sputnik).
References
External links
ja:アマチュア衛星
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