Nera Inmarsat-c, Руководство по обслуживанию, Страница: 83 / 228

5.3 Status monitor
5-9
- Current TDM: TDM type (NCS common TDM or LES TDM)
- MES Status: Busy or Idle
- GPS Status:
When GGA sentence is input from the external GPS, the status of the external GPS is
displayed as follows.
CST (Cold Start): Calculates without the almanac data.
ACQ (Acquired): Acquires the almanac data.
IMP (Impossible): The reception is not available.
INT (Interrupted): The interruption occurs during GPS reception.
ALM: Receives the almanac data.
2D/3D: Positioning in two or three dimensions
- DCE memory: The empty volume of the memory of the S-RAM in RF CON/CPU board.
- BBER: Bulletin Board Error Rate (%)
- C/N (Carrier/Noise): The quality of the received signal. “OK” appears when it is
more than 31dB.
- Send Level: Checks the transmission level. “OK” appears when it is more than 123
for transmitting, less than 32 for receiving.
(Normally, 0 appears for receiving, 255 for transmitting.)
- Rx AGC Level: Checks RX circuit. “OK” appears when the level is more than 60.
When the value is near 255, the receiving signal is not input to RF
CON/CPU board from the antenna unit. U14 (CPU) on RF CON/CPU
board generates AGC voltage to control pin diodes, CR31 and CR32
based on BPSK modulated I- and Q-signals.
- REF Offset Freq.: The difference between the RX frequency and the internal
oscillation frequency. “OK” appears when the Offset Freq. is
less than 150 Hz.
- Synthe Local: Checks of PLL synthesizer circuit on RF CON/CPU board.
- Antenna Power Supply: “NG” appears when the antenna cable is disconnected or
short.
- Water Temperature: MTW
- Water Current
Direction: Direction of the tide (VDR) Depth: Depth of water (DBT)
Speed: Speed of the tide (VDR)
Note) Refer 5.3.2 for the underlined item.