The GPS system was deployed by the Department of
Defense for improved navigation, positioning, and timing purposes.There are 24 satellites circling earth
twice every day.Dual-frequency
satellites broadcast L1 (~1.6 GHz) and L2 (~1.2 GHz) signals that are
received by GPS receivers and converted into position and time information.
While it is raining, if the Integrated
Precipitable Water Vapor (IPWV) is still increasing, then more rain will
follow.Scientists are looking for
characteristic signatures to determine IPWV and flash flood relationships.
The result of a noise comparison test performed
on broadband resonant quartz barometers showed that the broadband resonant
barometers had power spectral density noise levels a factor of 100 lower
(20 dB) than the next best transducer.
When the MET packages are deployed at the
GPS receiver sites, careful attention must be paid to the design of the
barometer pressure port because wind-induced errors can consume the entire
0.3 hPa pressure accuracy budget.