JCSAT-3 was a

geostationary A geostationary orbit, also referred to as a geosynchronous equatorial orbit''Geostationary orbit'' and ''Geosynchronous (equatorial) orbit'' are used somewhat interchangeably in sources. (GEO), is a circular geosynchronous orbit in altitude ...

communications satellite A communications satellite is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth. C ...

designed and manufactured by

Hughes Hughes may refer to: People * Hughes (surname) * Hughes (given name) Places Antarctica * Hughes Range (Antarctica), Ross Dependency * Mount Hughes, Oates Land * Hughes Basin, Oates Land * Hughes Bay, Graham Land * Hughes Bluff, Victoria La ...

(now

Boeing The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, telecommunications equipment, and missiles worldwide. The company also provides leasing and product ...

) on the

HS-601 The Boeing 601 (sometimes referred to as the BSS-601, and previously as the HS-601) is a communications satellite bus designed in 1985 and introduced in 1987 by Hughes Space and Communications Company. The series was extremely popular in the 199 ...

satellite bus A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held. Bus-derived satellites are opposed to specially produced satellites. Bus-d ...

. It was originally ordered by

JSAT Corporation JSAT Corporation (JSAT) was the first private Japanese satellite operator, which owned the JSAT satellites, as well as operated and partially owned the N-Star with NTT DoCoMo. Its origins can be traced to the funding of Japan Communications S ...

, which later merged into the

SKY Perfect JSAT Group The SKY Perfect JSAT Group is a Japanese corporate group that claims to be Asia's largest satellite communication and multi-channel pay TV company. It owns the SKY PerfecTV! satellite broadcasting service and the SKY Perfect Well Think content s ...

. It has a mixed

Ku-band The Ku band () is the portion of the electromagnetic spectrum in the microwave range of frequencies from 12 to 18 gigahertz (GHz). The symbol is short for "K-under" (originally german: Kurz-unten), because it is the lower part of the ori ...

and C-band payload and operated on the 128° East

longitude Longitude (, ) is a geographic coordinate that specifies the east–west position of a point on the surface of the Earth, or another celestial body. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter l ...

until it was replaced by

JCSAT-3A JCSAT-3A, known as JCSAT-10 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Lockheed Martin on the A2100 platform. Satellite description The spacecraft w ...

Satellite description

The spacecraft was designed and manufactured by

on the HS-601 satellite bus. It had a launch mass of , a dry mass of and a 12-year design life. When stowed for launch, its dimensions were . With its solar panels fully extended it spanned , and its width when its antennas were fully deployed was . Its power system generated approximately 5 kW of power thanks to two wings with four solar panels each. It also had a single NiH₂ battery composed of 30

cells Cell most often refers to: * Cell (biology), the functional basic unit of life Cell may also refer to: Locations * Monastic cell, a small room, hut, or cave in which a religious recluse lives, alternatively the small precursor of a monastery w ...

and a 200 Ah charge. It would serve as the main satellite on the 128° East longitude position of the JSAT fleet. Its propulsion system was composed of an R-4D-11-300 liquid apogee engine (LAE) with a thrust of . It also used had 12

bipropellant The highest specific impulse chemical rockets use liquid propellants (liquid-propellant rockets). They can consist of a single chemical (a monopropellant) or a mix of two chemicals, called bipropellants. Bipropellants can further be divided into ...

thrusters for station keeping and

attitude control Attitude control is the process of controlling the orientation of an aerospace vehicle with respect to an inertial frame of reference or another entity such as the celestial sphere, certain fields, and nearby objects, etc. Controlling vehicle ...

. It included enough propellant for orbit circularization and 12 years of operation. Its payload is composed of four octagonal antenna fed by twelve 36

MHz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that one he ...

and sixteen 27 MHz Ku-band plus twelve 27 MHz C-band

transponders In telecommunications, a transponder is a device that, upon receiving a signal, emits a different signal in response. The term is a blend of ''transmitter'' and ''responder''. In air navigation or radio frequency identification, a flight trans ...

for a total bandwidth of 1296 MHz. The Ku-band transponders have a

TWTA A traveling-wave tube (TWT, pronounced "twit") or traveling-wave tube amplifier (TWTA, pronounced "tweeta") is a specialized vacuum tube that is used in electronics to amplify radio frequency (RF) signals in the microwave range. The TWT belongs t ...

output power of 63 watts while the twelve C-band transponders have 34 watts of power.

History

In 1993, Japan Communications Satellite Company and Satellite Japan Corporation merged to form Japan Satellite Systems Inc. (JCSAT). That same year, JCSAT ordered JCSAT-3, a third satellite from Hughes, but this time using the

platform. In 1995, JCSAT obtained a license for international service, and thus became a regional operator. On 29 August 1995 at 00:53:02 UTC, an

Atlas IIAS Atlas II was a member of the Atlas family of launch vehicles, which evolved from the successful Atlas missile program of the 1950s. The Atlas II was a direct evolution of the Atlas I, featuring longer first stage tanks, higher-performing engines ...

launching from

Cape Canaveral , image = cape canaveral.jpg , image_size = 300 , caption = View of Cape Canaveral from space in 1991 , map = Florida#USA , map_width = 300 , type =Cape , map_caption = Location in Florida , location ...

LC-36B successfully launched JCSAT-3 into orbit. It was positioned into the 128° East orbital longitude. On 20 April 2004, JSAT ordered a second satellite from

Lockheed Martin The Lockheed Martin Corporation is an American aerospace, arms, defense, information security, and technology corporation with worldwide interests. It was formed by the merger of Lockheed Corporation with Martin Marietta in March 1995. It ...

JCSAT-10 JCSAT-3A, known as JCSAT-10 before launch, is a geostationary communications satellite operated by SKY Perfect JSAT Group (JSAT) which was designed and manufactured by Lockheed Martin on the A2100 platform. Satellite description The spacecraft wa ...

. Based on the A2100-AX satellite bus, it would have a C-band and Ku-band payload and was expected to replace JCSAT-3 at the 128° East orbital longitude after its planned 2006 launch. On 11 August 2006, an

Ariane 5 ECA Ariane 5 is a European heavy-lift space launch vehicle developed and operated by Arianespace for the European Space Agency (ESA). It is launched from the Centre Spatial Guyanais (CSG) in French Guiana. It has been used to deliver payloads into ...

launched

(JCSAT-3A) along

Syracuse-3B Syracuse (french: Système de radiocommunication utilisant un satellite, ''satellite based radiocommunication system'') is a series of French military communications satellites. Syracuse is intended to ensure the French military can communicate ...

into a transfer orbit. Upon successful deployment at 128° East longitude, it was renamed JCSAT-3A. In March 2007, JCSAT-3 was retired and decommissioned.

References

{{Orbital launches in 1995 Communications satellites in geostationary orbit Satellites using the BSS-601 bus Spacecraft launched in 1995 Intelsat satellites Communications satellites of Japan Satellites of Japan