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How do you test a GPS antenna?
A GPS antenna cannot be tested effectively unless it is connected to a receiver. Simply connecting an antenna to a spectrum analyzer — a device that generates a signal and tests the signal reflected by the antenna — is not sufficient to diagnose problems.
When using a GPS receiver the receiver must?
A GPS receiver must collect and then convert signals from GPS satellites into measurements of position, velocity, and time. There is a challenge in that the GPS signal has low power. An orbiting GPS satellite broadcasts its signal across a cone of approximately 28º of arc.
What does a GPS receiver detect?
A GPS Receiver is a L-band radio processor capable of solving the navigation equations in order to determine the user position, velocity and precise time (PVT), by processing the signal broadcasted by GPS satellites.
How is the quality of a GPS signal measured?
The performance of a receiver is assessed by its ability to precisely measure the pseudorange and carrier phase, which depend on noise linked to the signals in the receiver’s tracking loops. The quality of the signal in the presence of noise is measured by the signal-to- noise ratio, SNR. The larger the ratio is, the stronger the signal is.
Which is an important property of a GPS antenna?
The gain pattern is also an important property of a GPS antenna. It describes its sensitivity over some range of elevation and azimuth angles and its ability to discriminate against some multipath signals. The GPS antennas are typically omnidirectional with a nondirectional pattern in azimuth and a directional pattern in elevation angle.
How can I improve the accuracy of my GPS?
However, their accuracy worsens near buildings, bridges, and trees. High-end users boost GPS accuracy with dual-frequency receivers and/or augmentation systems. These can enable real-time positioning within a few centimeters, and long-term measurements at the millimeter level.
What makes GPS more accurate for civilian use?
Using two GPS frequencies improves accuracy by correcting signal distortions caused by Earth’s atmosphere. Dual-frequency GPS equipment is commercially available for civilian use, but its cost and size has limited it to professional applications. With augmentation systems, civilian users can actually receive better GPS accuracy than the military.