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GPS Block IIF
GPS Block IIF, or GPS IIF is an interim class of GPS (satellite) which were used to bridge the gap between previous Navstar Global Positioning System generations until the GPS Block III satellites became operational. They were built by Boeing, operated by the United States Air Force, and launched by the United Launch Alliance (ULA) using Evolved Expendable Launch Vehicles (EELV). They are the final component of the Block II GPS constellation to be launched. On 5 February 2016, the final Block IIF satellite was successfully launched, completing the series. The spacecraft have a mass of and a design life of 12 years. Like earlier GPS satellites, Block IIF spacecraft operate in semi-synchronous medium Earth orbits, with an altitude of approximately , and an orbital period of twelve hours. The satellites supplement and partially replace the GPS Block IIA satellites that were launched between 1990 and 1997 with a design life of 7.5 years. The final satellite of the Block IIA ser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boeing
The Boeing Company, or simply Boeing (), is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support services. Boeing is among the largest global aerospace manufacturers; it is the fourth-largest defense contractor in the world based on 2022 revenue and is the largest exporter in the United States by dollar value. Boeing was founded by William E. Boeing in Seattle, Washington, on July 15, 1916. The present corporation is the result of the merger of Boeing with McDonnell Douglas on August 1, 1997. As of 2023, the Boeing Company's corporate headquarters is located in the Crystal City neighborhood of Arlington County, Virginia. The company is organized into three primary divisions: Boeing Commercial Airplanes (BCA), Boeing Defense, Space & Security (BDS), and Boeing Global Services (BGS). In 2021, Boeing recorded $62.3billion in sales. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orbital Period
The orbital period (also revolution period) is the amount of time a given astronomical object takes to complete one orbit around another object. In astronomy, it usually applies to planets or asteroids orbiting the Sun, moons orbiting planets, exoplanets orbiting other stars, or binary stars. It may also refer to the time it takes a satellite orbiting a planet or moon to complete one orbit. For celestial objects in general, the orbital period is determined by a 360° revolution of one body around its primary, ''e.g.'' Earth around the Sun. Periods in astronomy are expressed in units of time, usually hours, days, or years. Its reciprocal is the orbital frequency, a kind of revolution frequency, in units of hertz. Small body orbiting a central body According to Kepler's Third Law, the orbital period ''T'' of two point masses orbiting each other in a circular or elliptic orbit is: :T = 2\pi\sqrt where: * ''a'' is the orbit's semi-major axis * ''G'' is the gravitationa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sirius
Sirius is the brightest star in the night sky. Its name is derived from the Greek word (Latin script: ), meaning 'glowing' or 'scorching'. The star is designated Canis Majoris, Latinized to Alpha Canis Majoris, and abbreviated CMa or Alpha CMa. With a visual apparent magnitude of −1.46, Sirius is almost twice as bright as Canopus, the next brightest star. Sirius is a binary star consisting of a main-sequence star of spectral type A0 or A1, termed Sirius A, and a faint white dwarf companion of spectral type DA2, termed Sirius B. The distance between the two varies between 8.2 and 31.5 astronomical units as they orbit every 50 years. Sirius appears bright because of its intrinsic luminosity and its proximity to the Solar System. At a distance of , the Sirius system is one of Earth's nearest neighbours. Sirius is gradually moving closer to the Solar System and it is expected to increase in brightness slightly over t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA-232
USA-232, also known as GPS IIF-2, and GPS SVN-63, is an American navigation satellite which forms part of the Global Positioning System. It was the second of twelve Block IIF satellites to be launched. Built by Boeing and launched by United Launch Alliance, USA-232 was launched at 06:41 UTC on 16 July 2011, atop a Delta IV carrier rocket, flight number D355, flying in the Medium+(4,2) configuration. The launch took place from Space Launch Complex 37B at the Cape Canaveral Air Force Station, and placed USA-232 directly into medium Earth orbit. As of 24 July 2011, USA-232 was in an orbit with a perigee of , an apogee of , a period of 729.16 minutes, and 55.0 degrees of inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle between a reference plane and the orbital plane or axis of direction of the orbiting object. For a satellite orbiting the Eart ... to the equator. It is used to broadcast the PRN 01 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Canaveral Space Launch Complex 37
Space Launch Complex 37 (SLC-37), previously Launch Complex 37 (LC-37), is a launch complex on Cape Canaveral Space Force Station, Florida. Originally built to support the Apollo program, the complex consists of two launch pads: LC-37A and SLC-37B. Pad 37A has never been used, while 37B hosted Saturn I and Saturn IB launches in the 1960s as well as Delta IV and Delta IV Heavy launches from 2002 to 2024. Currently, the pad is not officially leased to anyone. However, SpaceX is expected to become the next tenant of SLC-37 for use as a launch site for Starship, so far possessing a limited right of entry and a draft environmental impact statement. History Saturn I and IB (1964–1968) Launch Complex 37 began construction in 1959, being envisioned to be a second site to launch the experimental heavy-lift Saturn rockets, joining Launch Complex 34 (LC-34) to the south. Originally, it was planned to be the launch site for an Earth orbit rendezvous (EOR) strategy to potentially ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cape Canaveral Space Force Station
Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the station is the primary launch site for the Space Force's Eastern RangeCAST 1999, p. 1-12. with four launch pads currently active (Space Launch Complexes 36, 40, 41 and 46). The facility is south-southeast of NASA's Kennedy Space Center on adjacent Merritt Island, with the two linked by bridges and causeways. The Cape Canaveral Space Force Station Skid Strip provides a runway close to the launch complexes for military airlift aircraft delivering heavy and outsized payloads to the Cape. A number of American space exploration pioneers were launched from CCSFS, including the first U.S. Earth satellite (1958), first U.S. astronaut (1961), first U.S. astronaut in orbit (1962), first two-man U.S. spacecraft (1965), first U.S. uncrewed lu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Delta IV
Delta IV was a group of five expendable launch systems in the Delta rocket family. It flew 45 missions from 2002 to 2024. Originally designed by Boeing's Defense, Space and Security division for the Evolved Expendable Launch Vehicle (EELV) program, the Delta IV became a United Launch Alliance (ULA) product in 2006. The Delta IV was primarily a launch vehicle for United States Air Force (USAF) military payloads, but was also used to launch a number of United States government non-military payloads and a single commercial satellite. The Delta IV had two main versions which allowed the family to cover a range of payload sizes and masses: the Medium (which had four configurations) and Heavy. The final flight of Medium occurred in 2019. The final flight of Heavy was in April 2024. Delta IV vehicles were built in the ULA facility in Decatur, Alabama. Final assembly was completed at the launch site by ULA: at the horizontal integration facility for launches from SLC-37B pad at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polaris
Polaris is a star in the northern circumpolar constellation of Ursa Minor. It is designated α Ursae Minoris (Latinisation of names, Latinized to ''Alpha Ursae Minoris'') and is commonly called the North Star or Pole Star. With an apparent magnitude that fluctuates around 1.98, it is the brightest star in the constellation and is readily visible to the naked eye at night. The position of the star lies less than angular distance, 1° away from the north celestial pole, making it the current northern pole star. The stable position of the star in the northern celestial hemisphere, Northern Sky makes it useful for celestial navigation, navigation. As the closest Cepheid variable its distance is used as part of the cosmic distance ladder. The revised ''Hipparcos'' stellar parallax gives a distance to Polaris of about , while the successor mission Gaia (spacecraft), ''Gaia'' gives a distance of about . Although appearing to the naked eye as a single point of light, Polar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Error Analysis For The Global Positioning System
The error analysis for the Global Positioning System is important for understanding how GPS works, and for knowing what magnitude of error should be expected. The GPS makes corrections for receiver clock errors and other effects but there are still residual errors which are not corrected. GPS receiver position is computed based on data received from the satellites. Errors depend on geometric dilution of precision and the sources listed in the table below. Overview User equivalent range errors (UERE) are shown in the table. There is also a numerical error with an estimated value, \ \sigma_ , of about . The standard deviations, \ \sigma_R, for the coarse/acquisition (C/A) and precise codes are also shown in the table. These standard deviations are computed by taking the square root of the sum of the squares of the individual components (i.e., RSS for root sum squares). To get the standard deviation of receiver position estimate, these range errors must be multiplied by the a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Jamming
Radio jamming is the deliberate blocking of or interference with wireless communications.https://apps.fcc.gov/edocs_public/attachmatch/DA-12-347A1.pdf Enforcement Advisory No. 2012-02 FCC Enforcement Advisory Cell Jammers, GPS Jammers, and Other Jamming Devices Consumer Alert: Using or Importing Jammers is Illegal In some cases, jammers work by the transmission of radio signals that disrupt telecommunications by decreasing the signal-to-noise ratio. The concept can be used in wireless data networks to disrupt information flow. It is a common form of censorship in totalitarian countries, in order to prevent foreign radio stations in border areas from reaching the country. Jamming is usually distinguished from interference that can occur due to device malfunctions or other accidental circumstances. Devices that simply cause interference are regulated differently. Unintentional "jamming" occurs when an operator transmits on a busy frequency without first checking whether it is in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
USA-203
USA-203, also known as GPS IIR-20(M), GPS IIRM-7 and GPS SVN-49, is an American navigation satellite which was intended to become part of the Global Positioning System. It was the sixth of seven Block IIRM satellites to be launched, and the twentieth of twenty one Block IIR satellites overall. It was built by Lockheed Martin, using the AS-4000 satellite bus, and had a mass of . USA-203 was launched at 08:34 UTC on 24 March 2009, atop a Delta II carrier rocket, flight number D340, flying in the 7925-9.5 configuration. The launch took place from Space Launch Complex 17A at the Cape Canaveral Air Force Station, and placed USA-203 into a transfer orbit. The satellite raised itself into medium Earth orbit using a Star-37FM apogee motor. USA-203 is located in an orbit with a perigee of , an apogee of , a period of 718 minutes, and 55.8 degrees of inclination Orbital inclination measures the tilt of an object's orbit around a celestial body. It is expressed as the angle bet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GPS Signals
GPS signals are broadcast by Global Positioning System satellites to enable satellite navigation. Using these signals, receivers on or near the Earth's surface can determine their Position, Velocity and Time (PVT). The GPS satellite constellation is operated by the 2nd Space Operations Squadron (2SOPS) of Space Delta 8, United States Space Force. GPS signals include ranging signals, which are used to measure the distance to the satellite, and navigation messages. The navigation messages include ephemeris data which are used both in trilateration to calculate the position of each satellite in orbit and also to provide information about the time and status of the entire satellite constellation, called the almanac. There are four GPS signal specifications designed for civilian use. In order of date of introduction, these are: L1 C/A, L2C, L5 and L1C. L1 C/A is also called the ''legacy signal'' and is broadcast by all currently operational satellites. L2C, L5 and L1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
