Datawell BV RX-C4, Руководство пользователя

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“heave: ??? cm”
This message indicates a transmission error.
Figure 4.6. Receiving data.
Normally, after power up or loss of signal, the receiver will display “synchronizing” for some
time. When the quality of the received signal is high enough, the “heave” messages will be
displayed. If the signal quality becomes too low, the receiver will try to resynchronize to the
buoy signal.
NOTE: The process of synchronization can take anything between 30 seconds to several
minutes. The time needed to reach synchronization depends on several factors like
signal-strength, interference, noise bursts and type of buoy.
4.2.1 GPS position
When the buoy being received is equipped with a GPS module, the GPS position of the buoy is
shown on the display. The GPS position message is “rotated” with the heave message according
to the scheme shown in figure 4.7.
Figure 4.7. Heave message and GPS message rotating scheme.
Note that the update rate of the GPS position is defined by the received buoy. Please refer to the
buoy documentation for more information.
4.2.2 Signal quality
When displaying heave, a signal quality bar graph is shown on the display, see figure 4.6. The
signal quality indication is derived from the “frame error rate” (FER) parameter. A full-scale
deflection of this bar indicates that no errors are detected in the incoming data (FER = 0%)
while no deflection at all indicates that all received data contains errors (FER = 100%).