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10.2.1.2 Meinberg GNSS Receiver (GPS, GLONASS, Galileo, BeiDou)
High accuracy and the possibility of the world wide operation around the clock are the main features of the
system, which receive his time information from the satellites of the American GPS (Global Positioning System),
the European Galileo, the Russian GLONASS (Global Navigation Satellite System) and the Chinese BeiDou.
The Global Positioning System (GPS) is a GNSS operated by the US department of defense. Its purpose
is to provide position, velocity and time for civilian and defense users on a global basis. The system currently
consists of 32 medium earth orbit satellites and several ground control stations.
GLONASS is a GNSS operated by Russian Federation department of defense. Its purpose is to provide
position, velocity and time for civilian and defense users on a global basis. The system consists of 24 medium
earth orbit satellites and ground control stations. The GLONASS satellites circle the earth once on three
orbital lanes in height of 19100km in about 12 hours.
Galileo is a GNSS operated by the European Union. Its purpose is to provide position, velocity and time
for civilian users on a global basis. The system is currently not fully operational. It is eventually expected to
consist of 30 medium earth orbit satellites. At the time of writing (early 2016), the Galileo system was still
under development with only a few fully operational SVs. Therefore, the precise performance and reliability of
u-blox receivers when receiving Galileo signals is effectively impossible to guarantee.
BeiDou is a GNSS operated by China. Its purpose is to initially provide position, velocity and time for
users in Asia. In a later stage when the system is fully deployed it will have worldwide coverage. The full
system will consist of five geostationary, five inclined geosynchronous and 27 medium earth orbit satellites, as
well as control, upload and monitoring stations.
Characteristics
The GNS module is a combined GPS / Galileo / GLONASS / BeiDou receiver and operates with the "Standard
Positioning Service" (GPS) or "Standard Precision" (Galileo, GLONASS, BeiDou). The data stream from the
satellites is decoded by the microprocessor of the system. By analyzing the data, the GNSS system time can
be reproduced very precisely. Different running times of the signals from the satellites to the receiver are auto-
matically compensated by determining the receiver position. By tracking the main oscillator (Oven Controlled
Xtal Oscillator, OCXO) a high frequency accuracy is achieved. At the same time, the aging-induced drift of the
quartz is compensated. The current correction value for the oscillator is stored in a non-volatile memory of the
system. This receiver is suitable not only for stationary operation but also for mobile use.
48 Date: 22nd June 2020 microSync