iXBlue OCEANO RT2500S Series, Руководство пользователя

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OCEANO RT2500S/RT5000S Series – User Guide
II.4 Transponder Mode
The main function of the transponder mode is to trigger the acoustic transmission of the
transponder by acoustic means. 2 independent channels (factory configurable only) can
be enabled or disabled by means of the serial link and/or acoustic telecommand.
•
IIF channel (Individual Interrogation Frequency) for the sequential response mode
•
CIF channel (Common Interrogation Frequency) for the simultaneous response mode
Acoustic reception frequencies (transponder mode):
•
Interrogation frequency : from 8.5 to 16 kHz by increments of 0.5 kHz
•
Turn-around time : programmable from 20 to 200 ms in 1 ms increments on NMEA
command via serial link
•
Blanking time : programmable from 1 to 31 s in 1 s increments on NMEA command
via serial link
•
10 ms CIF and IIF interrogation pulses, tonal frequency
•
CIF and IIF reception frequencies are only factory configurable
CIF interrogation

IRF reply (Individual Reply Frequency): Tonal type
IIF interrogation

CRF reply (Common Reply Frequency): M-FSK type by default (code
22)
Figure 1 – Operating mode block diagram
IRF is a 10 ms tonal pulse (only the frequency can be programmed by NMEA command).
CRF is a NMEA-programmable pulse. The following parameters are programmable:
•
Pulse type : tonal (duration 10 ms) or M-FSK (duration 25 ms),
•
Frequency : from 7.5 to 18 kHz in 500 Hz increments for a tonal pulse,
•
Code number : from 22 to 31 for a M-FSK pulse (code 22 as standard) 14.5 – 17.5
kHz spectral bandwidth
•
Transmit levels (CRF or IRF)
 191 ± 4 dB re. 1 µPa at 1 m within 8 to 17.5 kHz bandwidth
 193 ± 2 dB re. 1 µPa at 1 m at 12 kHz bandwidth
MU–RT8x1–AN–001 Ed. M – September 2013 6