The future of electronic tracking device
So what is coming? Some day there may be as many as 80 satellites from GPS, GLONASS, GALILEO, QZSS, and others. If so the systems will provide users with a variety of signals and codes. The availability of many more satellites will enable new applications in areas where the current lack of satellites has been a hindrance. For civil users, Personal GPS tracker will provide more protection from interference, ability to compensate for ionospheric delays with pseudoranges, and wide-laning or even trianing capabilities. For military users, there will be greater antijam capability and security. For everybody, there will be improvement in accuracy, availability, integrity, and reliability.
It looks as if the GNSS is on its way. So it is no surprise that there is great anticipation from a business perspective, but from a user’s point of view the situation is not unlike the advent of GPS more than 30 years ago. Much is promised but little assured. New capabilities will be available, but exactly what and exactly when is by no means certain. Nevertheless, it is prudent to consider the ramifications of a constellation including QZSS, GLONASS, Beidou, GALILEO, and GPS satellites.
More Satellites
How many more? GPS and GLONASS together provide the user with ~2 times the satellites than does GPS alone. In other words, if one considers that 6 satellites are normally above a user’s horizon with GPS alone, there will usually be about 12 available with GPS and GLONASS combined. If GPS and GALILEO are considered together there are ~2½ times or about 15 satellites typically available to a user. The number increases to 21 or ~3½ times more satellites with all three GPS, GLONASS, and GALILEO together and particularly if Beidou and QZSS are included.
Accessibility
In a sense, the more satellites the better the performance, particularly among trees and in urban canyons, those places where signals bounce and scatter, and multipath abounds.
Flexibility
When more satellites are overhead, the user has more flexibility. For example, since there are 6 satellites in a window available to a electronic tracker, the user may be able to increase the mask angle to decrease the multipath and still have 4 satellites to observe. Imagine if there were 12, 15, or even 21 satellites and you can see how more satellites can mean better accessibility in restricted environments.
Reliability
Also, the more diverse the maintenance of the components of GNSS, the less chance of overall system failure. The United States, Russia, Japan, the European Union, and China all have infrastructure in place to support their contribution to GNSS. Under such circumstances simultaneous outages across the entire GNSS constellation are extremely unlikely.
Faster Positioning
More measurements in shorter time means observation periods can be shortened without degrading accuracy and interference can be ameliorated more easily. In short, better accuracy can be achieved in less time.
Faster Initialization
Also, with more satellites available, the time to first fix for carrier-phase receivers, the period when the receiver is solving for the integers, downloading the almanac and so forth, also know as initialization, will be shortened significantly. And fixed solution accuracy will be achieved more quickly. Today dual-frequency carrier-phase solutions are accurate but noisy, but with the new signals available on L2C, L5, and other GNSS signals, dual-frequency solutions will be directly enhanced.
More GPS tracking solutions at http://www.jimilab.com/ .
It looks as if the GNSS is on its way. So it is no surprise that there is great anticipation from a business perspective, but from a user’s point of view the situation is not unlike the advent of GPS more than 30 years ago. Much is promised but little assured. New capabilities will be available, but exactly what and exactly when is by no means certain. Nevertheless, it is prudent to consider the ramifications of a constellation including QZSS, GLONASS, Beidou, GALILEO, and GPS satellites.
More Satellites
How many more? GPS and GLONASS together provide the user with ~2 times the satellites than does GPS alone. In other words, if one considers that 6 satellites are normally above a user’s horizon with GPS alone, there will usually be about 12 available with GPS and GLONASS combined. If GPS and GALILEO are considered together there are ~2½ times or about 15 satellites typically available to a user. The number increases to 21 or ~3½ times more satellites with all three GPS, GLONASS, and GALILEO together and particularly if Beidou and QZSS are included.
Accessibility
In a sense, the more satellites the better the performance, particularly among trees and in urban canyons, those places where signals bounce and scatter, and multipath abounds.
Flexibility
When more satellites are overhead, the user has more flexibility. For example, since there are 6 satellites in a window available to a electronic tracker, the user may be able to increase the mask angle to decrease the multipath and still have 4 satellites to observe. Imagine if there were 12, 15, or even 21 satellites and you can see how more satellites can mean better accessibility in restricted environments.
Reliability
Also, the more diverse the maintenance of the components of GNSS, the less chance of overall system failure. The United States, Russia, Japan, the European Union, and China all have infrastructure in place to support their contribution to GNSS. Under such circumstances simultaneous outages across the entire GNSS constellation are extremely unlikely.
Faster Positioning
More measurements in shorter time means observation periods can be shortened without degrading accuracy and interference can be ameliorated more easily. In short, better accuracy can be achieved in less time.
Faster Initialization
Also, with more satellites available, the time to first fix for carrier-phase receivers, the period when the receiver is solving for the integers, downloading the almanac and so forth, also know as initialization, will be shortened significantly. And fixed solution accuracy will be achieved more quickly. Today dual-frequency carrier-phase solutions are accurate but noisy, but with the new signals available on L2C, L5, and other GNSS signals, dual-frequency solutions will be directly enhanced.
More GPS tracking solutions at http://www.jimilab.com/ .
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