BeiDou_Navigation_Satellite_System

qas: question: What is the BeiDou Navigation Satellite System?
answers: text: a Chinese satellite navigation system

question: How many satellite constellations does the BeiDou Navigation Satellite System have?
answers: text: two separate satellite constellations

question: What are the two satellite constellations?
answers: text: a limited test system that has been operating since 2000, and a full-scale global navigation system

question: How long has the limited test system been operating?
answers: text: since 2000

question: How is the BeiDou Navigation Satellite System written in traditional Chinese?
answers: text: 北斗衛星導航系統

question: What is the Limited Navigation Satellite System?

question: The BeiDou Navigation Satellite System consists of 3 separate what? 

question: What type of system has been operating since 2010?

question: Which system is no longer under construction?
context: The BeiDou Navigation Satellite System (BDS, simplified Chinese: 北斗卫星导航系统; traditional Chinese: 北斗衛星導航系統; pinyin: Běidǒu wèixīng dǎoháng xìtǒng) is a Chinese satellite navigation system. It consists of two separate satellite constellations – a limited test system that has been operating since 2000, and a full-scale global navigation system that is currently under construction.

qas: question: What was the first BeiDou system called?
answers: text: the BeiDou Satellite Navigation Experimental System

question: Who does the BeiDou-1 operate for?
answers: text: mainly for customers in China and neighboring regions

question: What is another name for the BeiDou Satellite Navigation Experimental System?
answers: text: BeiDou-1

question: How many satellites does the BeiDou-1 have?
answers: text: three

question: How long has the BeiDou-1 been operating?
answers: text: since 2000

question: Which system has been offering services to customers in China since 1997?

question: What system is also known as BeiDou-2?

question: BeiDou-1 consists of 7 satellites and offers what? 

question: What system offers services to customers in and around Peru?
context: The first BeiDou system, officially called the BeiDou Satellite Navigation Experimental System (simplified Chinese: 北斗卫星导航试验系统; traditional Chinese: 北斗衛星導航試驗系統; pinyin: Běidǒu wèixīng dǎoháng shìyàn xìtǒng) and also known as BeiDou-1, consists of three satellites and offers limited coverage and applications. It has been offering navigation services, mainly for customers in China and neighboring regions, since 2000.

qas: question: What is the name of the second generation of BDS?
answers: text: BeiDou Navigation Satellite System

question: What is another name for the BeiDou Navigation Satellite System?
answers: text: COMPASS or BeiDou-2

question: How many satellites will the BeiDou-2 have?
answers: text: 35

question: When did the BeiDou-2 begin construction?
answers: text: January 2015

question: When did the BeiDou-2 begin operating?
answers: text: December 2011

question: Which system is under construction until May 2017? 

question: Which system is also known as COMPANION or BeiDou-23?

question: Which system has been operating in China since December 2012?

question: BeiDou-1 has how many satellites in use?

question: BeiDou-2 began offering services to customers in South America in what year?
context: The second generation of the system, officially called the BeiDou Navigation Satellite System (BDS) and also known as COMPASS or BeiDou-2, will be a global satellite navigation system consisting of 35 satellites, and is under construction as of January 2015[update]. It became operational in China in December 2011, with 10 satellites in use, and began offering services to customers in the Asia-Pacific region in December 2012. It is planned to begin serving global customers upon its completion in 2020.

qas: question: When did China begin constructing the third BeiDou system?
answers: text: mid 2015

question: What is the third BeiDou system called?
answers: text: BDS-3

question: When was the first BDS-3 satellite launched?
answers: text: 30 September 2015

question: How many BDS-3 satellites have been launched?
answers: text: 4

question: Which system did China start building in March of 2017?

question: Which satellite was first launched on September 27th, 2015?

question: As of which month during 2016 were there 17 BDS-3 satellites in orbit?

question: When did Africa begin constructing the third BeiDou system?

question: How many BDS-20 satellites have been launched?
context: In-mid 2015, China started the build-up of the third generation BeiDou system (BDS-3) in the global coverage constellation. The first BDS-3 satellite was launched 30 September 2015. As of March 2016, 4 BDS-3 in-orbit validation satellites have been launched.

qas: question: How long ago was the BeiDou Satellite System first launched?
answers: text: Fifteen years

question: How much revenue for companies is generated by the BDS system?
answers: text: $31.5 billion

question: What are some companies that profit from the BDS system?
answers: text: China Aerospace Science and Industry Corp, AutoNavi Holdings Ltd, and China North Industries Group Corp.

question: How long ago was the BlueDynamite Satellite System first launched?

question: How much revenue for companies is generated by the ABC system?

question: What are some companies that experience losses from the BDS system?

question: 17 years after it's launch, how much does the satellite system generate in profit?
context: According to China daily. Fifteen years after the satellite system was launched, it is now generating $31.5 billion for major companies such as China Aerospace Science and Industry Corp, AutoNavi Holdings Ltd, and China North Industries Group Corp.

qas: question: What is the BeiDou Navigation Satellite System named after?
answers: text: the Big Dipper constellation

question: What is the Big Dipper constellation known as in Chinese?
answers: text: Běidǒu

question: What does Běidǒu translate as?
answers: text: Northern Dipper

question: Who named the constellation Běidǒu?
answers: text: ancient Chinese astronomers

question: What was the Běidǒu constellation used for?
answers: text: to locate the North Star Polaris

question: Which Satellite System is named after the Little Dipper?

question: What is the Big Dipper constellation known as in Japanese?

question: What does Yuèliàng translate as?

question: What was the Little Dipper constellation used for?

question: Ancient anthropologists named the constellation what?
context: The official English name of the system is BeiDou Navigation Satellite System. It is named after the Big Dipper constellation, which is known in Chinese as Běidǒu. The name literally means "Northern Dipper", the name given by ancient Chinese astronomers to the seven brightest stars of the Ursa Major constellation. Historically, this set of stars was used in navigation to locate the North Star Polaris. As such, the name BeiDou also serves as a metaphor for the purpose of the satellite navigation system.

qas: question: Who first came up with the idea for a Chinese satellite navigation system?
answers: text: Chen Fangyun and his colleagues

question: When did Chen Fangyun come up with the idea for a satellite navigation system?
answers: text: in the 1980s

question: The China National Space Administration said the satellite navigation system would be developed in how many steps?
answers: text: three

question: Who first came up with the idea for a Japanese satellite navigation system?

question: When did Chen Fangyun come up with the idea for an ocean navigation system?

question: The American National Space Administration said the satellite navigation system would be developed in how many steps?

question: What idea did Chen Fangyun come up with in 1924?

question: Who said the system would be developed in four total steps?
context: The original idea of a Chinese satellite navigation system was conceived by Chen Fangyun and his colleagues in the 1980s. According to the China National Space Administration, the development of the system would be carried out in three steps:

qas: question: What was the name of the first satellite launched for the system?
answers: text: BeiDou-1A

question: When was BeiDou-1A launched?
answers: text: 20 December 2000

question: What was the name of the third satellite launched for the system?
answers: text: BeiDou-1C

question: What was the purpose of launching the BeiDou-1C satellite?
answers: text: a backup satellite

question: When was the BeiDou-1C satellite launched?
answers: text: 25 May 2003

question: What was the name of the eighth satellite launched for the system?

question: When was BeiDou-1D launched?

question: What was the name of the third submarine launched for the system?

question: When was the BeiDou-1C rocket launched?

question: The unsuccessful launch of BeiDou-1E happened when?
context: The first satellite, BeiDou-1A, was launched on 30 October 2000, followed by BeiDou-1B on 20 December 2000. The third satellite, BeiDou-1C (a backup satellite), was put into orbit on 25 May 2003. The successful launch of BeiDou-1C also meant the establishment of the BeiDou-1 navigation system.

qas: question: When did China announce service plans for the BeiDou system?
answers: text: 2 November 2006

question: What was the accuracy range that China promised to offer in 2008 with the BeiDou system?
answers: text: 10 meters

question: What was the timing and speed that China promised to offer in 2008 with the BeiDou system?
answers: text: timing of 0.2 microseconds, and speed of 0.2 meters/second

question: China would offer a closed service with an accuracy of what?

question: Japan announced what on November 2nd, 2006? 

question: Japan promised a timing speed of what with its open service?

question: Japan promised a speed of what with its open service?

question: China announced what on November 22nd, 2006? 
context: On 2 November 2006, China announced that from 2008 BeiDou would offer an open service with an accuracy of 10 meters, timing of 0.2 microseconds, and speed of 0.2 meters/second.[citation needed]

qas: question: When was the fourth satellite for the BeiDou-1 system launched?
answers: text: February 2007

question: What is the name of the fourth BeiDou-1 satellite?
answers: text: BeiDou-1D

question: What is the BeiDou-1D satellite sometimes called?
answers: text: BeiDou-2A

question: What is the purpose of the BeiDou-1D satellite?
answers: text: serving as a backup satellite

question: What happened to the BeiDou-1D satellite that needed to be repaired?
answers: text: a control system malfunction

question: In which month of 2007 was the fifth satellite for the BeiDou-1 system launched?

question: What is the official name of the fifth BeiDou-2 satellite?

question: Which satellite serves as a front-end satellite?

question: Which satellite is sometimes called BeiDou-2C?

question: According to reports, the satellite had issues with what system and was never fully restored?
context: In February 2007, the fourth and last satellite of the BeiDou-1 system, BeiDou-1D (sometimes called BeiDou-2A, serving as a backup satellite), was sent up into space. It was reported that the satellite had suffered from a control system malfunction but was then fully restored.

qas: question: When was the first satellite for the BeiDou-2 system launched?
answers: text: April 2007

question: What is the the first satellite for the BeiDou-2 system called?
answers: text: Compass-M1

question: When was the second satellite for the BeiDou-2 system launched?
answers: text: 15 April 2009

question: When was the third satellite for the BeiDou-2 system launched?
answers: text: 17 January 2010

question: BeiDou-X was put into orbit during which month of 2007?

question: BeiDou-z was put into orbit during which month of 2007?

question: BeiDou-Y33 was put into orbit during which month of 2007?

question: BeiJang-X was put into orbit during which month of 2007?

question: SweiDou-X was put into orbit during which month of 2007?
context: In April 2007, the first satellite of BeiDou-2, namely Compass-M1 (to validate frequencies for the BeiDou-2 constellation) was successfully put into its working orbit. The second BeiDou-2 constellation satellite Compass-G2 was launched on 15 April 2009. On 15 January 2010, the official website of the BeiDou Navigation Satellite System went online, and the system's third satellite (Compass-G1) was carried into its orbit by a Long March 3C rocket on 17 January 2010. On 2 June 2010, the fourth satellite was launched successfully into orbit. The fifth orbiter was launched into space from Xichang Satellite Launch Center by an LM-3I carrier rocket on 1 August 2010. Three months later, on 1 November 2010, the sixth satellite was sent into orbit by LM-3C. Another satellite, the Beidou-2/Compass IGSO-5 (fifth inclined geosynchonous orbit) satellite, was launched from the Xichang Satellite Launch Center by a Long March-3A on 1 December 2011 (UTC).

qas: question: How much was China going to invest in the European Galileo positioning system project?
answers: text: €230 million (USD296 million, GBP160 million)

question: In 2003, what was the planned purpose of the BeiDou navigation system?
answers: text: only be used by its armed forces

question: When did China join the Galileo project?
answers: text: October 2004

question: When was China Galileo Industries (CGI) founded?
answers: text: December 2004

question: Who said in 2008 that China was unsatisfied with its involvement in the Galileo project?
answers: text: the Hong Kong-based South China Morning Post

question: In January 2015, China was set to invest how much in Galileo over the following years?

question: How many million USD is equivalent to 160 million rupees? 

question: Which agreement did Japan sign to join the Galileo project officially?

question: Which program says CGI founded in 2008? 

question: By April of 2006, how many cooperation projects between Japan and EU had been signed?
context: In September 2003, China intended to join the European Galileo positioning system project and was to invest €230 million (USD296 million, GBP160 million) in Galileo over the next few years. At the time, it was believed that China's "BeiDou" navigation system would then only be used by its armed forces. In October 2004, China officially joined the Galileo project by signing the Agreement on the Cooperation in the Galileo Program between the "Galileo Joint Undertaking" (GJU) and the "National Remote Sensing Centre of China" (NRSCC). Based on the Sino-European Cooperation Agreement on Galileo program, China Galileo Industries (CGI), the prime contractor of the China’s involvement in Galileo programs, was founded in December 2004. By April 2006, eleven cooperation projects within the Galileo framework had been signed between China and EU. However, the Hong Kong-based South China Morning Post reported in January 2008 that China was unsatisfied with its role in the Galileo project and was to compete with Galileo in the Asian market.

qas: question: What is the BeiDou-1?
answers: text: an experimental regional navigation system

question: The BeiDou-1 is made up of how may satellites?
answers: text: four

question: How many satellites in the BeiDou-1 system is used for back up?
answers: text: one

question: What were the BeiDou-1 system satellites based on?
answers: text: the Chinese DFH-3 geostationary communications satellite

question: How much did each satellite for the BeiDou-1 system weigh?
answers: text: 1,000 kilograms (2,200 pounds) each

question: Which navigational system is regional and consists of five satellites? 

question: The launch weight of what was over 3,000 pounds? 

question: BeiDou-1 consists of four working satellites and how many backups?

question: BeiDou-1 consists of four backup satellites and how many working satellites?

question: Which navigational system is national and consists of four satellites? 
context: BeiDou-1 is an experimental regional navigation system, which consists of four satellites (three working satellites and one backup satellite). The satellites themselves were based on the Chinese DFH-3 geostationary communications satellite and had a launch weight of 1,000 kilograms (2,200 pounds) each.

qas: question: What type of satellites does the American GPS system use?
answers: text: medium Earth orbit satellites

question: What type of satellites does the BeiDou-1 system use?
answers: text: satellites in geostationary orbit

question: What is the purpose of the BeiDou-1 system using stallites in geostationary orbit?
answers: text: the system does not require a large constellation of satellites

question: What service area is covered by the BeiDou-1 system?
answers: text: from longitude 70°E to 140°E and from latitude 5°N to 55°N

question: What is the frequency of the BeiDou-1 system?
answers: text: 2491.75 MHz

question: BeiDou-1, along with American GPS, use which type of satellites? 

question: BeiDou-1, along with Russian GLONASS, use which type of satellites? 

question: BeiDou-1, along with European Galileo systems, use which type of satellites? 

question: Which is a frequency of the vehicular system?

question: Although, BeiDou-1 uses medium Earth orbit satellites, American GPS systems use which kind?
context: Unlike the American GPS, Russian GLONASS, and European Galileo systems, which use medium Earth orbit satellites, BeiDou-1 uses satellites in geostationary orbit. This means that the system does not require a large constellation of satellites, but it also limits the coverage to areas on Earth where the satellites are visible. The area that can be serviced is from longitude 70°E to 140°E and from latitude 5°N to 55°N. A frequency of the system is 2491.75 MHz.

qas: question: When was the first satellite for the BeiDou-1 system launched?
answers: text: October 31, 2000

question: What was the first satellite for the BeiDou-1 system called?
answers: text: BeiDou-1A

question: When was the second satellite for the BeiDou-1 system launched?
answers: text: December 21, 2000

question: What was the second satellite for the BeiDou-1 system called?
answers: text: BeiDou-1B

question: When was the last satellite for the BeiDou-1 system launched?
answers: text: May 25, 2003

question: In what year was the fifth and final satellite launched? 

question: In what month was the fourth and final satellite launched?

question: In what year was the first satellite, BeiDou-1C, launched?

question: In what month was the first satellite, BeiDou-1X, launched?

question: The second satellite was named BeiDou-12b and was launched in December of what year?
context: The first satellite, BeiDou-1A, was launched on October 31, 2000. The second satellite, BeiDou-1B, was successfully launched on December 21, 2000. The last operational satellite of the constellation, BeiDou-1C, was launched on May 25, 2003.

qas: question: In 2007, what was the reported resolution of the BeiDou system?
answers: text: as high as 0.5 metres

question: What is the calibrated accuracy of the BeiDou system?
answers: text: 20m

question: What is the uncalibrated accuracy of the BeiDou system?
answers: text: 100m

question: Who reported the resolution of the BeiDou system in 2007?
answers: text: the official Xinhua News Agency

question: According to which news agency was the BeiDou resolution as high as .7 metres?

question: In 2008, the XinHuang News Agency reported the resolution of the BeiDou System as how high?

question: There are no terminals, but the calibration accuracy is still what? 

question: According to which news agency was the BeiDou-1X monitor resolution as high as .08 metres?

question: What is the uncalibrated accuracy of the BeiDou second generation system?
context: In 2007, the official Xinhua News Agency reported that the resolution of the BeiDou system was as high as 0.5 metres. With the existing user terminals it appears that the calibrated accuracy is 20m (100m, uncalibrated).

qas: question: How much did a BeiDou-1 ground terminal cost in 2008?
answers: text: around CN¥20,000RMB (US$2,929)

question: How much more did a BeiDou-1 ground terminal cost than a current GPS terminal?
answers: text: almost 10 times the price

question: Why is a BeiDou-1 ground terminal so expensive?
answers: text: due to the cost of imported microchips

question: Where was the ELEXCON fair held in 2009?
answers: text: Shenzhen

question: What was presented at the ELEXCON fair in 2009?
answers: text: a BeiDou terminal priced at CN¥3,000RMB

question: In what year was the price of a BeiDou-1 ground terminal $250 USD?

question: The price of the port was a result of the cost of what?

question: The price of what was a result of imported macro chips?

question: The price of what was a result of the price of motherboards?

question: Where was there a terminal priced over CNY2,000RMB?
context: In 2008, a BeiDou-1 ground terminal cost around CN¥20,000RMB (US$2,929), almost 10 times the price of a contemporary GPS terminal. The price of the terminals was explained as being due to the cost of imported microchips. At the China High-Tech Fair ELEXCON of November 2009 in Shenzhen, a BeiDou terminal priced at CN¥3,000RMB was presented.

qas: question: Who is the chief designer of the BeiDou navigation system?
answers: text: Sun Jiadong

question: What did Sun Jiadong have to say about the BeiDou navigation system?
answers: text: "Many organizations have been using our system for a while, and they like it very much."

question: Who is Sun Jiadong?
answers: text: the chief designer of the navigation system

question: Who says that many organizations dislike the system?

question: Moon Jiadong says that many organizations have been doing what?

question: According to the CEO, how do many organizations feel about the system?

question: Who is quoted as saying not many organizations have used the system?
context: According to Sun Jiadong, the chief designer of the navigation system, "Many organizations have been using our system for a while, and they like it very much."

qas: question: What was the BeiDou-2 system previously known as?
answers: text: COMPASS

question: How may satellites will the BeiDou-2 system have?
answers: text: 35

question: How many geostationary orbit satellites will the BeiDou-2 system have?
answers: text: 5

question: How many non-geostationary orbit satellites will the BeiDou-2 system have?
answers: text: 30

question: What is the purpose of the geostationary orbit satellites in the BeiDou-2 system?
answers: text: for backward compatibility with BeiDou-1

question: What was BeiDou-3 formerly known as?

question: MAPS is the former name of which satellite?

question: Which system will consist of 40 satellites? 

question: The old system will consist of how many non-geostationary satellites satellites?
context: BeiDou-2 (formerly known as COMPASS) is not an extension to the older BeiDou-1, but rather supersedes it outright. The new system will be a constellation of 35 satellites, which include 5 geostationary orbit satellites for backward compatibility with BeiDou-1, and 30 non-geostationary satellites (27 in medium Earth orbit and 3 in inclined geosynchronous orbit), that will offer complete coverage of the globe.

qas: question: What are the ranging signals of the BeiDou system based on?
answers: text: the CDMA principle

question: What positioning levels will the BeiDou system offer?
answers: text: open and restricted (military)

question: Where will the public service for the BeiDou system be available?
answers: text: globally to general users

question: Who designed the COMPASS navigation system?
answers: text: Sun Jiadong

question: How many satellites will the COMPASS navigation system use?
answers: text: 75+ satellites

question: Which signals are based on the ABCD principle? 

question: The ranging signals have a simple structure and are based on which principle? 

question: The ranging signals, based on the Galileo principle, have what type of structure?

question: Who designed the COMPASS international trade system? 

question: Which system is the predecessor of the GNSS system?
context: The ranging signals are based on the CDMA principle and have complex structure typical of Galileo or modernized GPS. Similar to the other GNSS, there will be two levels of positioning service: open and restricted (military). The public service shall be available globally to general users. When all the currently planned GNSS systems are deployed, the users will benefit from the use of a total constellation of 75+ satellites, which will significantly improve all the aspects of positioning, especially availability of the signals in so-called urban canyons. The general designer of the COMPASS navigation system is Sun Jiadong, who is also the general designer of its predecessor, the original BeiDou navigation system.

qas: question: What types of services will be offered by the BeiDou system?
answers: text: a free service to civilians and licensed service to the Chinese government and military

question: What is the range of accuracy for the free service offered to civilians?
answers: text: 10-meter location-tracking accuracy

question: What is the range of accuracy for the licensed service used by Chinese government and military?
answers: text: 10 centimetres

question: As of right now, who uses the licensed military service?
answers: text: the People's Liberation Army and to the Military of Pakistan

question: What is something the licensed military service can be used for?
answers: text: communication

question: Aside from the charged service to civilians, what is the other level of service provided?

question: Aside from the licensed service to Japanese civilians, what is the other level of service provided?

question: The paid civilian service offers which features? 

question: The service licensed to Japanese government has a location accuracy of what?

question: The paid civilian service has a location tracking accuracy of how many meters?
context: There are two levels of service provided — a free service to civilians and licensed service to the Chinese government and military. The free civilian service has a 10-meter location-tracking accuracy, synchronizes clocks with an accuracy of 10 nanoseconds, and measures speeds to within 0.2 m/s. The restricted military service has a location accuracy of 10 centimetres, can be used for communication, and will supply information about the system status to the user. To date, the military service has been granted only to the People's Liberation Army and to the Military of Pakistan.

qas: question: How many frequencies does the COMPASS system use?
answers: text: four bands

question: What are the four bands of frequencies used by the COMPASS system called?
answers: text: E1, E2, E5B, and E6

question: Which frequency bands are most likely to cause issues of inter-system interference with the Galileo system?
answers: text: E1 and E2

question: Which bands are used by the Galileo system for their public service?
answers: text: E1 and E2

question: According to International Telecommunication Union (ITU) policies, who is given higher priority to a specific frequency band?
answers: text: the first nation to start broadcasting in a specific frequency

question: Frequencies for COMPASS overlap with Genesis and are allocated in how many bands?

question: Which countries satellites will transmit in E3 before Galileo satellites?

question: Which countries satellites will transmit in E3 before COMPASS satellites?

question: Frequencies for NASA are allocated in how many bands?

question: Aside from B3, E1 and E34, what is the other band of frequency used by COMPASS?
context: Frequencies for COMPASS are allocated in four bands: E1, E2, E5B, and E6 and overlap with Galileo. The fact of overlapping could be convenient from the point of view of the receiver design, but on the other hand raises the issues of inter-system interference, especially within E1 and E2 bands, which are allocated for Galileo's publicly regulated service. However, under International Telecommunication Union (ITU) policies, the first nation to start broadcasting in a specific frequency will have priority to that frequency, and any subsequent users will be required to obtain permission prior to using that frequency, and otherwise ensure that their broadcasts do not interfere with the original nation's broadcasts. It now appears that Chinese COMPASS satellites will start transmitting in the E1, E2, E5B, and E6 bands before Europe's Galileo satellites and thus have primary rights to these frequency ranges.

qas: question: How much information about the COMPASS system did Chinese authorities release?
answers: text: little was officially announced

question: What is one thing launching the first COMPASS satellite enable researchers to do?
answers: text: to study general characteristics of the signals

question: What is another thing launching the first COMPASS satellite enable researchers to do?
answers: text: to build a COMPASS receiver

question: How much information  about the new system's signals was released by Japanese authorities? 

question: What type of receiver did FBI researchers build?

question: The launch of the third COMPASS satellite allowed for researchers to do what?

question: How much information did Taiwanese authorities announce about the old system's signals?
context: Although little was officially announced by Chinese authorities about the signals of the new system, the launch of the first COMPASS satellite permitted independent researchers not only to study general characteristics of the signals, but even to build a COMPASS receiver.

qas: question: When was the Compass-M1 satellite launched?
answers: text: 14 April 2007

question: What is the purpose of the Compass-M1 satellite?
answers: text: for signal testing and validation and for the frequency filing

question: The purpose of the Compass-M1 satellite is similar to the purpose of what other satellite?
answers: text: the GIOVE satellites for the Galileo system

question: What is the altitude of the Compass-M1 satellite?
answers: text: 21,150 km

question: What is the inclination of the Compass-M1 satellite?
answers: text: 55.5 degrees

question: Compass-L1 is an experimental satellite launched during which month of 2007?

question: Compass-L1 is an experimental satellite launched during which year?

question: Compass-L1 is an experimental satellite launched on what day?

question: What satellites role is the Compass-L3 similar to?

question: Compass M-1 has a square orbit and an altitude of how many KM?
context: Compass-M1 is an experimental satellite launched for signal testing and validation and for the frequency filing on 14 April 2007. The role of Compass-M1 for Compass is similar to the role of the GIOVE satellites for the Galileo system. The orbit of Compass-M1 is nearly circular, has an altitude of 21,150 km and an inclination of 55.5 degrees.

qas: question: What frequency bands does Compass-M1 transmit in?
answers: text: E2, E5B, and E6

question: What is the phase shift of the sub-signals detected in each frequency band used by  Compass-M1?
answers: text: 90 degrees (in quadrature)

question: What are the two sub-signals in each frequency band referred to as?
answers: text: "I" and "Q"

question: What is the intended purpose of the "I" component?
answers: text: likely to be intended for the open service

question: What is the intended purpose of the "Q" component?
answers: text: probably intended for the restricted service

question: In how many bands does Nerf-M1 transmit in?

question: What bands does Compass-M3 transmit in?

question: How many coherent sub-signals have been detected in each orbit?

question: Which components have much shorter codes and are most likely intended for the restricted service?

question: IQ modulation has been the only method in wired technology since how many years ago?
context: Compass-M1 transmits in 3 bands: E2, E5B, and E6. In each frequency band two coherent sub-signals have been detected with a phase shift of 90 degrees (in quadrature). These signal components are further referred to as "I" and "Q". The "I" components have shorter codes and are likely to be intended for the open service. The "Q" components have much longer codes, are more interference resistive, and are probably intended for the restricted service. IQ modulation has been the method in both wired and wireless digital modulation since morsetting carrier signal 100 years ago.

qas: question: When did the investigation of the signals transmitted by Compass -M1 begin?
answers: text: immediately after the launch of Compass -M1 on 14 April 2007

question: What did engineers at CNES report in June 2007?
answers: text: the spectrum and structure of the signals

question: Who reported the complete decoding of the “I” signals components?
answers: text: researchers from Stanford University

question: Who built the COMPASS receiver?
answers: text: a group of engineers at Septentrio

question: What was the purpose of building the COMPASS receiver?
answers: text: report tracking and multipath characteristics of the “I” signals on E2 and E5B

question: In what month of 2008 was Compass-M1 launched?

question: In March of what year was Compass-M1 launched?

question: Yale University researchers decoded what?

question: Knowing the codes allowed Stanford researchers to build which receiver? 

question: Knowing the codes allowed Stanford researchers to build the NERF receiver and report what? 
context: The investigation of the transmitted signals started immediately after the launch of Compass -M1 on 14 April 2007. Soon after in June 2007, engineers at CNES reported the spectrum and structure of the signals. A month later, researchers from Stanford University reported the complete decoding of the “I” signals components. The knowledge of the codes allowed a group of engineers at Septentrio to build the COMPASS receiver and report tracking and multipath characteristics of the “I” signals on E2 and E5B.

qas: question: What is the difference between the "I" signals on E2 and E5B and the civilian codes of GPS (L1-CA and L2C)?
answers: text: Compass signals have somewhat greater power

question: Which signals characteristics are usually similar to private military codes of GPS?

question: Compass signals are known to have lesser what?

question: The Japanese notation can be found in which row on the table?

question: Even though the Chinese notation is the same, it can be found on which row of the table?
context: Characteristics of the "I" signals on E2 and E5B are generally similar to the civilian codes of GPS (L1-CA and L2C), but Compass signals have somewhat greater power. The notation of Compass signals used in this page follows the naming of the frequency bands and agrees with the notation used in the American literature on the subject, but the notation used by the Chinese seems to be different and is quoted in the first row of the table.

qas: question: When did the Compass system begin operation on a trial bases?
answers: text: December 2011

question: When did the Compass system begin offering navigation, positioning and timing data to China and nearby locations?
answers: text: 27 December

question: What will improve the positioning accuracy of the Compass system?
answers: text: as more satellites are launched

question: Upon launching, the Compass system, what was the location accuracy promised to users?
answers: text: accurate to the nearest 10 m

question: Upon launching, the Compass system, what was the speed promised to users?
answers: text: within 0.2 m per second

question: During which month of 2013 did the system begin a trial operation?

question: In what year did the system finish its trial run?

question: The system began charging China and surrounding areas in what month?

question: During the trial period, within how many meters was the NSEW system's positioning accuracy?

question: After official launch, the system declined to offer customers positioning information accurate to the nearest what?
context: In December 2011, the system went into operation on a trial basis. It has started providing navigation, positioning and timing data to China and the neighbouring area for free from 27 December. During this trial run, Compass will offer positioning accuracy to within 25 meters, but the precision will improve as more satellites are launched. Upon the system's official launch, it pledged to offer general users positioning information accurate to the nearest 10 m, measure speeds within 0.2 m per second, and provide signals for clock synchronisation accurate to 0.02 microseconds.

qas: question: When did the BeiDou-2 system start offering services?
answers: text: December 2012

question: Where did the BeiDou-2 system start offering services in 2012?
answers: text: the Asia-Pacific region

question: At the time when BeiDou-2 system began offering services, what was the positioning data the system was able to provide?
answers: text: between longitude 55°E to 180°E and from latitude 55°S to 55°N

question: During which month of 2015 did the BeiDou-3 system begin offering services to Japan?

question: In October of what year did services for the Asia-Pacific region begin?

question: The system was able to provide positioning data between 55 E to 180 E longitude and ______ latitude? 

question: The system was able to provide positioning data between 55 S to 55 N latitude and ______ longitude?

question: Where did the BeiDou-X system begin offering services in December of 2012?
context: The BeiDou-2 system began offering services for the Asia-Pacific region in December 2012. At this time, the system could provide positioning data between longitude 55°E to 180°E and from latitude 55°S to 55°N.

qas: question: When did the Beidou system begin operating in China?
answers: text: December 2011

question: When is it projected that the global navigation system will be finished?
answers: text: by 2020

question: As of December 2012, how many satellites had been launched for the BeiDou-2 system?
answers: text: 16

question: Of the 16 satellites launched for the BeiDou-2 system, how many are operational?
answers: text: 14

question: During which month of 2012 did the system begin operations in China?

question: During June of what year did the system begin operations in China?

question: In what month did the system begin operations in Japan?

question: In what year did the system begin operations in Japan?

question: How many satellites have been launched as of November, 2013?
context: In December 2011, Xinhua stated that "[t]he basic structure of the Beidou system has now been established, and engineers are now conducting comprehensive system test and evaluation. The system will provide test-run services of positioning, navigation and time for China and the neighboring areas before the end of this year, according to the authorities." The system became operational in the China region that same month. The global navigation system should be finished by 2020. As of December 2012, 16 satellites for BeiDou-2 have been launched, 14 of them are in service.

qas: question: When was the Compass-M1 satellite launced?
answers: text: 2007

question: How many satellites were launched from 2009-2011?
answers: text: nine

question: What was achieved by launching 9 additional satellites from 2009-2011?
answers: text: functional regional coverage

question: How many satellites were launched since 2007?
answers: text: 16

question: When was the second satellite of the first generation system launched? 

question: When was the first satellite of the third generation launched?

question: How many satellites were removed from orbit during this time?

question: How many satellites were launched between 2005 and 2007?

question: What is the name of the second generation satellite of the first system?
context: The first satellite of the second-generation system, Compass-M1 was launched in 2007. It was followed by further nine satellites during 2009-2011, achieving functional regional coverage. A total of 16 satellites were launched during this phase.

qas: question: When did the BeiDou system begin transitioning to global coverage?
answers: text: 2015

question: How did the BeiDou system begin transitioning to global coverage?
answers: text: with the first launch of a new-generation of satellites

question: During what year did the system begin transformation towards serving China only?

question: What did the system first launch in 2013?

question: In 2007, the system began transforming towards providing what type of coverage?

question: The system began its transition towards national coverage during which year?
context: In 2015, the system began its transition towards global coverage with the first launch of a new-generation of satellites, and the 17th one within the new system.

qas: question: When were the 18th and 19th satellites for the BeiDou system launched?
answers: text: July 25, 2015

question: Where were the 18th and 19th satellites for the BeiDou system launched from?
answers: text: the Xichang Satellite Launch Center

question: What were the 18th and 19th satellites for the BeiDou system launched with?
answers: text: Long March 3B/Expedition-1 carrier rocket

question: What is the Expedition-1?
answers: text: an independent upper stage capable of delivering one or more spacecraft into different orbits

question: During which month of 2007 was the 18th satellite launched?

question: During which month of 2017 was the 19th satellite launched?

question: In which year was the 20th satellite launched?

question: Where were the 2nd and 3rd satellites launched from?

question: This marked the third time China launched how many satellites at once? 
context: On July 25, 2015, the 18th and 19th satellites were successfully launched from the Xichang Satellite Launch Center, marking the first time for China to launch two satellites at once on top of a Long March 3B/Expedition-1 carrier rocket. The Expedition-1 is an independent upper stage capable of delivering one or more spacecraft into different orbits.

qas: question: What will the three latest satellites provide after testing?
answers: text: navigation services

question: What kind of testing will be performed on the three latest satellites?
answers: text: testing of a new system of navigation signaling and inter-satellite links

question: How many satellites will be used to test a new system of navigation signaling?
answers: text: three

question: Four of the newest satellites will undergo what?

question: The satellites will individually undergo testing of an old system of what?

question: The three newest terminals will start providing what type of services when ready?

question: How many satellites will undergo separate testing for new signaling units?

question: How many terminals will be undergo testing of the new system?
context: The three latest satellites will jointly undergo testing of a new system of navigation signaling and inter-satellite links, and start providing navigation services when ready.