HIGH DATA RATE RECEIVER
HDR-4G+ USER’S MANUAL
Ref. DTU 100782
Is.Rev 3.5
Date: June 1, 2021
© Safran Data Systems – IMP000074 e14r1
This document is the property of Safran Data Systems.
It cannot be duplicated or distributed without expressed written consent.
Other Status & Alarms 4.5.4.1.2.2
IF carrier level in dBm. The nominal AGC range is from -10 to -50 dBm.
Degraded measurement if the level of the received signal is not within these limits.
Offset from the expected IF carrier frequency (real frequency - expected
frequency). Expressed in Hz. This value depends both on the oscillator drift (on-
board and ground equipment) and on the Doppler conditions.
Offset from the expected bit rate (real BR - expected BR). Expressed in bit per
second.
In DVB-S2 and SCCC modes, the Bit Rate Offset is replaced by the Symbol
Rate Offset
Energy per bit in a 1-Hz noise bandwidth, measured at the bit synchronizer input.
Expressed in dB.
In DVB-S2 and SCCC modes, the Eb/No is replaced by the Es/No (Es: Energy
per symbol
In OQPSK mode, the following additional status appears at the GUI for monitoring the I/Q delay
compensation:
When OQPSK I/Q delay compensation is:
OFF No compensation
ON (Auto) Detected compensation value (Note 1)
ON (Fixed) Fixed compensation value (Note 1 and 2)
Note 1: The I/Q shift compensation applies to Q channel (after IF to base-band down-conversion). As
the OQPSK demodulation is ambiguous, the sign of the status changes in accordance with the
demodulation ambiguity.
Note 2: In fixed mode, as the demodulation is ambiguous, both signs are tested and an error
estimation is done in both cases. If the best error value is inferior to a certain threshold, the automate
will be locked on this sign. If the two errors are not acceptable (i.e. if the programmed compensation
does not reflect the real delay), the automate will indefinitely change the sign of the compensation,
which is reflected by the sign change of this status. In this unstable configuration, the I/Q shift value
must be refined.
Important: in UQPSK (AQPSK, AUQPSK, AUSQPSK) mode, status BR OFFSET, Eb/No and BIT
SYNC described here above are for the I Channel. The following additional status appears at the GUI
for monitoring the Q Channel:
Offset from the expected bit rate for the Q Channel (real Q Channel BR –
expected Q Channel BR). Expressed in bit per second.
Energy per bit in a 1-Hz noise bandwidth, measured at the bit synchronizer input
for the Q Channel. Expressed in dB.
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