GPS Tracking Solution - GPS–Galileo–Glonass Constellations
Despite similarities, there are some issues in the consistency GNSS issues as you know. For example, you may recall that the roll out of the new systems is not coordinated. In other words GPS ( GPS Tracking Device ) Modernization, GLONASS replenishment, and QZSS and Galileo deployment have not been synchronized. Despite much cooperation there is no clear agreement among nations that launches and operational capabilities of GLONASS, GALILEO, GPS, QZSS, and Beidou will happen in the same time frame. Also there are differences between GLONASS and GPS regarding CDMA and FDMA. There are also differences in the time standards between the two systems. Not to mention the overlap between the GPS M-code and Beidou. It is important that these inconsistencies are worked out technologically because apart from the less sophisticated applications for GNSS interoperability will be required. For the full potential of the system to realize multiple GNSS, frequencies will need to work together.
In other words they require as many satellites as possible delivering signals that can be used in conjunction with one another any time, any place uses for things such as routing of emergency vehicles, or the electronic tracker based automated machine control system now in used in construction. Mining, agriculture, aircraft control, and so forth, are depending more and more on satellite navigation systems. These industries have high costs and high risks and not only require high accuracy but reliability as well. If GNSS can deliver inexpensive receivers tracking the maximum number of satellites broadcasting the maximum number of signals, it will live up to the fondest hopes of not only many individuals but also many industries as well.
Currently, the GPS satellites in orbit around the earth include none of the first
launched GPS satellites, which were known as Block I (1978–1985). None of these
are functional today. The last Block I was retired in late 1995. These satellites needed help from the Control Segment to do the momentum dumping necessary to maintain their attitude control. They carried two cesium and two rubidium frequency standards and had a design life of 5 years, though some operated for double that.
Some years later, the modernized GPS constellation may be in place, including L5 and GALILEO. Just considering GPS and GALILEO there could be 60 or so satellites in orbit and available. Including GLONASS and QZSS it is feasible that ~80 satellites could be available. If these constellations become reality a typical user could find 10 20 satellites above the horizon anywhere, any time. The algorithms currently necessary for the achievement of high accuracy with carrier-phase ranging may be simplified since many of the new GNSS signals will be carrying a civilian code. Generally speaking, code correlation is a more straightforward problem than is carrier differencing. This may lead to less complicated receivers. This presents the possibility that they will be less expensive.
In fact, the goal of a single receiver that can track all the old and new satellite signals with a significant performance improvement looks possible. But after all, the main attraction of interoperability between these systems is the greatly increased number of satellites and signals, better satellite availability, better dilution of precision, immediate ambiguity resolution on long baselines with three-frequency data, better accuracy in urban settings, and fewer multipath worries. Those are some of the things we look forward to. It is beginning to look like at least some of those things are achievable.
More GPS Solution at http://www.jimilab.com/ .
In other words they require as many satellites as possible delivering signals that can be used in conjunction with one another any time, any place uses for things such as routing of emergency vehicles, or the electronic tracker based automated machine control system now in used in construction. Mining, agriculture, aircraft control, and so forth, are depending more and more on satellite navigation systems. These industries have high costs and high risks and not only require high accuracy but reliability as well. If GNSS can deliver inexpensive receivers tracking the maximum number of satellites broadcasting the maximum number of signals, it will live up to the fondest hopes of not only many individuals but also many industries as well.
Currently, the GPS satellites in orbit around the earth include none of the first
launched GPS satellites, which were known as Block I (1978–1985). None of these
are functional today. The last Block I was retired in late 1995. These satellites needed help from the Control Segment to do the momentum dumping necessary to maintain their attitude control. They carried two cesium and two rubidium frequency standards and had a design life of 5 years, though some operated for double that.
Some years later, the modernized GPS constellation may be in place, including L5 and GALILEO. Just considering GPS and GALILEO there could be 60 or so satellites in orbit and available. Including GLONASS and QZSS it is feasible that ~80 satellites could be available. If these constellations become reality a typical user could find 10 20 satellites above the horizon anywhere, any time. The algorithms currently necessary for the achievement of high accuracy with carrier-phase ranging may be simplified since many of the new GNSS signals will be carrying a civilian code. Generally speaking, code correlation is a more straightforward problem than is carrier differencing. This may lead to less complicated receivers. This presents the possibility that they will be less expensive.
In fact, the goal of a single receiver that can track all the old and new satellite signals with a significant performance improvement looks possible. But after all, the main attraction of interoperability between these systems is the greatly increased number of satellites and signals, better satellite availability, better dilution of precision, immediate ambiguity resolution on long baselines with three-frequency data, better accuracy in urban settings, and fewer multipath worries. Those are some of the things we look forward to. It is beginning to look like at least some of those things are achievable.
More GPS Solution at http://www.jimilab.com/ .
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