SEPTENTRIO PolaRx5S, User Manual

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E 100 Hz Output Rate
As described in the previous chapters, ionospheric monitoring typically involves sampling
I &Q correlation and carrier phase data at a 50 Hz rate. However, the PolaRx5S also supports
100 Hz rate for advanced research.
To prevent overloading the receiver ’ s CPU when operating at 100 Hz output rate, the only
SBF block that should be output at 100 Hz is the I QCorr block. That block contains the I &Q
correlation values and the carrier phase modulo 65.536 cycles. To be able to reconstruct the
full carrier phase at 100 Hz (i.e. to
fi x the 65.536-cycle ambiguity), it is su ffi cient to log the
MeasEpoch
SBF block at a lower rate, e.g. 1 Hz.
The
sfb2ismr
program, with the
-r
option, can be used to recover full carrier phase and
correlation values from a SBF fi le containing 100 Hz
IQCorr
blocks and 1 Hz
MeasEpoch
blocks. See Section 5.3.3 for details.
To avoid data gaps, it is recommended to use either the receiver ’ s USB or Ethernet
connection when operating at 100 Hz. The standard serial ports should not be used because
their bandwidth is too low to support such a high data throughput.
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