Recent innovations in GPS Tracking Device technology
Through the developments of a few decades, GPS is now even known by school children. GPS tracker has been very widely applied in several areas, such as air, sea and land navigation, low earth orbit (LEO) satellite orbit determination, static and kinematic positioning, flight-state monitoring, as well as surveying, etc. GPS has become a necessity for daily life, industry, research and education. GPS receivers are designed with many built-in features but only a few are essential for wilderness navigation. Any feature that requires the receiver to stay switched on for prolonged periods should be used sparingly as conserving battery power is an important consideration, especially in cold weather. Under certain conditions, built-in or optional features can enhance the performance of a GPS receiver.
Recent innovations in GPS technology have introduced ways to enhance precision, availability, and reliability in advanced receivers. These innovations address mitigation of multipath errors, receiver (antenna center) stability, and data reliability under adverse signal conditions.
Correction signal enabled receivers
Receivers that are designed to accept correction signals from differential GPS or spacebased augmentation systems can improve the accuracy of a position fix. The receiver must be within a certain radius of an operational ground station to derive any benefit, regardless whether the correction signals arrive via a satellite or directly from a ground station. If your receiver is too far from a ground station, the correction signals may not be relevant for your area.
External antennas
Powered external antennas can be connected to some receivers. These types of antennas amplify weak satellite signals and enhance your receiver’s ability to get a position fix under tree cover. Extra battery power is needed to operate the antenna. Position averaging Some receivers have a built-in position averaging feature that can improve the accuracy of a waypoint, which is a position fix stored in the receiver’s memory. For this feature to work, the receiver must be stationary for a period of time before storing the waypoint. A receiver that is switched on will repeatedly recalculate its position, allowing the software to work out the average of all the previously calculated position fixes. The longer the receiver stays switched on, the more position fixes are available for averaging and the more accurate the subsequently stored waypoint
In-Band and Out-of-Band Interference/Jamming Suppression
The operation of a GPS Tracking Device can be severely limited or completely disrupted in the presence of in-band or out-of band interference and jamming signals. Most receivers filter out-of-band noise, but few suppress interference within the band. The threat of the in-band interference and jamming signals increases daily as new communication systems are put in place and the radio frequency spectrum becomes more populated. The threat is not only from the interfering signals themselves but also from their harmonics that fall inside the GPS band.
Weak Signal/High Dynamics Tracking
Single point positioning is a sub-process of GPS data processing, which is needed in almost all electronic tracking devices data processing. Station coordinates and receiver clock error are determined with such a sub-process. Depending on the accuracy requirement, single point positioning can be done with single frequency code or phase data, dual frequency code or phase data, and combined code-phase data. Generally speaking, single point positioning has a lower accuracy than that of relative positioning, where systematic errors are reduced (through keeping the reference fixed). However, the receiver clock bias determined by single point positioning is accurate enough to correct the second type of clock error influence (the influence scaled by the velocity of the satellite).
Recent innovations in GPS technology have introduced ways to enhance precision, availability, and reliability in advanced receivers. These innovations address mitigation of multipath errors, receiver (antenna center) stability, and data reliability under adverse signal conditions.
Correction signal enabled receivers
Receivers that are designed to accept correction signals from differential GPS or spacebased augmentation systems can improve the accuracy of a position fix. The receiver must be within a certain radius of an operational ground station to derive any benefit, regardless whether the correction signals arrive via a satellite or directly from a ground station. If your receiver is too far from a ground station, the correction signals may not be relevant for your area.
External antennas
Powered external antennas can be connected to some receivers. These types of antennas amplify weak satellite signals and enhance your receiver’s ability to get a position fix under tree cover. Extra battery power is needed to operate the antenna. Position averaging Some receivers have a built-in position averaging feature that can improve the accuracy of a waypoint, which is a position fix stored in the receiver’s memory. For this feature to work, the receiver must be stationary for a period of time before storing the waypoint. A receiver that is switched on will repeatedly recalculate its position, allowing the software to work out the average of all the previously calculated position fixes. The longer the receiver stays switched on, the more position fixes are available for averaging and the more accurate the subsequently stored waypoint
In-Band and Out-of-Band Interference/Jamming Suppression
The operation of a GPS Tracking Device can be severely limited or completely disrupted in the presence of in-band or out-of band interference and jamming signals. Most receivers filter out-of-band noise, but few suppress interference within the band. The threat of the in-band interference and jamming signals increases daily as new communication systems are put in place and the radio frequency spectrum becomes more populated. The threat is not only from the interfering signals themselves but also from their harmonics that fall inside the GPS band.
Weak Signal/High Dynamics Tracking
Single point positioning is a sub-process of GPS data processing, which is needed in almost all electronic tracking devices data processing. Station coordinates and receiver clock error are determined with such a sub-process. Depending on the accuracy requirement, single point positioning can be done with single frequency code or phase data, dual frequency code or phase data, and combined code-phase data. Generally speaking, single point positioning has a lower accuracy than that of relative positioning, where systematic errors are reduced (through keeping the reference fixed). However, the receiver clock bias determined by single point positioning is accurate enough to correct the second type of clock error influence (the influence scaled by the velocity of the satellite).
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