米国发佈中国发射 Tianwang-1A Tianwang-1B Tianwang-1C 之消息
Beijing Launches Three More Amateur Radio Satellites
On September 25,2015 at 01:41 UT Beijing launched three satellites with
amateur radiopayloads from the Jiuquan Satellite Launch Center (JSLC)
in the
Gobidesert, Inner Mongolia. They were carried on a new launcher, Beijing’s
firstsolid-fuel rocket Chang Zheng 11 (CZ-11), and deployed in a 470 x
485km,
97.3 degree inclination Sun Synchronous Orbit (SSO).
This launchoccurred just over 5 days after nine satellites carrying amateur
radiopayloads were launched by Beijing from the Taiyuan Satellite Launch
Center(TSLC) in Shanxi on September 19 at 23:01 UT.
The satellites weredeveloped by students at the Nanjing University of
Aeronautics andAstronautics in collaboration with the Shanghai Engineering
Center forMicrosatellites (SECM).
The main goal of the mission is to experimentwith Software Defined Radio
(SDR) in space. The amateur radio payloads willbe used for exchanging
Telemetry, Tracking and Command (TT&C) informationwith the amateur radio
ground control station. Information about thetelemetry will be made
publicly
available so that radio amateurs aroundthe world may track and monitor the
health of the satellites.
Otherpayloads include a video camera along with receivers fordual-band
GPS/Beidou, Maritime Automatic Identification System (AIS) andAeronautical
Automatic Dependent Surveillance Broadcast (ADS-B).
UsingMEMS based cold-gas micropropulsion it is planned to demonstrate
formationflying by two of the CubeSats along with inter satellite
communication usingGAMALINK 2.4 GHz spread spectrum at 1 Mbps and the
CubeSat
Space Protocol(CSP).
The TW-1A and TW-1B CubeSats are 2U (20x10x10cm) in size whileTW-1C is 3U
(30x10x10cm).
Michael Chen BD5RV reports the satelliteshave these downlinks in the
435-438
MHz ITU Amateur Satellite Serviceallocation:
• Tianwang-1A (TW-1A / SECM): Camera, 435.645 MHz GMSK 4800/9600CSP TX
interval 10s
• Tianwang-1B (TW-1B / NJUST-2): AIS, 437.645 MHz GMSK4800/9600 CSP TX
interval 20s
• Tianwang-1C (TC-1C / NJFA-1): ADS-B,435.645 MHz GMSK 4800/9600 CSP TX
interval 10s
Note: TW-1A and 1C use thesame frequency.
On the same launch was the technology demonstrationsatellite Pujian-1 which
has WiFi for intra-satellitecommunications.
Object identification from information supplied by NicoJanssen PA0DLO and
Zhang Xuan BH4DBE:
TW-1A object 40928,2015-051B
TW-1B object 40927, 2015-051C, (other IDs: TianWang 1B,NJUST-2)
TW-1C object 40926, 2015-051D
Pujian 1 object 40925,2015-051A
Chang Zheng 11 (CZ-11) fourth stage object 40929,2015-051E
Keplerian Two Line Elements (TLEs) ‘Keps’ for new satelliteslaunched in
past
30 days
http://celestrak.com/NORAD/elements/tle-new.txtShanghaiEngineering Centre for Microsatellites
http://www.microsate.com/en/GAMALINKin Space
http://tekevernews.blogspot.co.uk/2015/07/gamalink-in-space.htmlIARUSatellite Frequency Coordination pages
http://amsat.org.uk/iaru/Satellitetracking information
http://amsat-uk.org/beginners/satellite-tracking/Addingnew satellites to SatPC32, Gpredict and Nova
http://amsat-uk.org/2013/11/23/adding-new-satellites-to-satpc32/[ANSthanks AMSAT-UK for the aboveinformation]
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