SEPTENTRIO PolaRx5TR, Reference Manual

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2 Operation Details
Chapter 2
Operation Details
This chapter describes the key processes implemented in the receiver and explains how they
can be configured.
2.1 Channel Allocation and Signal Selection
The receiver automatically allocates satellites to tracking channels up to the limit of the num-
ber of channels. It is possible to override this automatic channel allocation by forcing a satel-
lite to a given channel with the
setChannelAllocation
command. Also, a subset of satel-
lites or a whole constellation can be disabled with the
setSatelliteTracking
command.
For each satellite, the receiver tries to track all signal types enabled with the
setSignalTracking
command. For example, if that command enables the GPSL1CA,
GPSL2PY and GLOL1CA signals, GPS satellites will be tracked in dual-frequency mode
(GPSL1CA and GPSL2PY) and GLONASS satellites will be tracked in single-frequency mode
(GLOL1CA only). It is a good practice to only enable those signal types that are needed for
your application to avoid wasting tracking channels.
2.2 Generation of Measurements
For each tracked GNSS signal, the receiver generates a "measurement set", mainly consisting
of the following observables:
• a pseudorange in meters;
• a carrier phase in cycles;
• a Doppler in Hertz;
• a carrier-to-noise ratio in dB-Hz.
All data in a measurement set, and all measurement sets are taken at the same time, which
is referred to as the "measurement epoch". All the measurement sets taken at a given mea-
surement epoch are output in a
MeasEpoch
SBF block.
Several commands affect the way the receiver produces and outputs measurements:
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