Meinberg GPS165, Manual

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4 General information about GPS165XHS
4 General information about GPS165XHS
The Meinberg satellite receiver clocks of the GPS165xHS series are available with several options. This manual
describes the following models:
GPS165DHS
GPS165DAHS
GPS165/MOS/DHS
GPS165/MOS/DAHS
20-60 V DC 100-240 V AC 100-240 V DC
PhotoMos
relay outputs
Optocoupler
outputs
GPS165DHS GPS165DAHS
The variants differ in power supply and the type of DC-isolation of the programmable pulse outputs. The
differences are described in the relevant chapters, the name GPS165xHS is used whenever common features of
all types of clocks are specified.
The satellite receiver clock GPS165xHS has been designed to provide an extremly precise time reference
for the generation of programmable pulses. High precision available 24 hours a day around the whole world is
the main feature of the new system which receives it’s information from the satellites of the Global Positioning
System.
The Global Positioning System (GPS) is a satellite-based radio-positioning, navigation, and time-transfer
system. It was installed by the United States Departement of Defense and provides two levels of accuracy: The
Standard Positioning Service (SPS) and the Precise Positioning Service (PPS). While PPS is encrypted and
only available for authorized (military) users, SPS has been made available to the general public.
GPS is based on accurately measuring the propagation time of signals transmitted from satellites to the user´s
receiver. A nominal constellation of 24 satellites together with 3 active spares in six orbital planes 20000 km
over ground provides a minimum of four satellites to be in view 24 hours a day at every point of the globe. Four
satellites need to be received simultaneously if both receiver position (x, y, z) and receiver clock offset from
GPS system time must be computed. All the satellites are monitored by control stations which determine the
exact orbit parameters as well as the clock offset of the satellites´ on-board atomic clocks. These parameters
GPS165XHS Date: 5th November 2019 15