UltraReceiver User Manual
Receiver Setup
Issue No: 3
Page: 32
Ref: ULRX-ASUM-700X
Copyright © 2018 Vislink plc
Please see Figure 2-1 for a functional block diagram of the receiver.
The interleaver settings on the encoder define the required FEC (1/2 – 14/15) and also the
required Burst duration.
If the deinterleaver is On, no other parameters need to be set, the deinterleaver will
automatically extract the FEC and burst settings from the received stream.
The resultant ‘Interleave Delay’ and ‘Interleave Burst’ are then also displayed.
These parameters are a function of the Interleave FEC, Interleave Burst correction settings
in the encoder and also the ASI bitrate.
‘Delay’ is a function of the Interleave FEC value and Burst duration set on the transmitter
interleaver:
Delay = Burst * Denom.
NOTE: Where Denom is the FEC denominator.
For example:
Burst setting of 1000ms and FEC of 3/4 will result in a delay of 4000ms.
illustrates the limits in Burst length for the receiver at typical ASI bit rates.
NOTE: All figures are approximate.
Mode
Modulation Modulation FEC
ASI Bit Rate
(Mb/s)
Approx. Burst
Limit(s)
DVB-T
QPSK
1/2
6
8.1
DVB-T
QPSK
3/4
9
5.4
DVB-T
16QAM
1/2
12
4.0
DVB-T
16QAM
3/4
18
2.7
DVB-T
64QAM
1/2
18
2.7
DVB-T
64QAM
3/4
27
1.8
LMS-T (10M)
QPSK
2/3
9
5.3
LMS-T (10M)
16QAM
2/3
18
2.6
LMS-T (20M)
QPSK
2/3
18
2.6
LMS-T (20M)
16QAM
2/3
37
1.3
Table 6-5
Burst Limits Overview
NOTE: Due to the large buffers involved in the interleaving process, significant time may be
required after any adjustments are made before a stable picture is decoded.
The UltraReceiver can encapsulate an ASI stream into an IP (Internet Protocol) stream for
transport over Ethernet infrastructure. It can also receive such streams and recover the ASI
stream from within it. This uses UDP (User Datagram Protocol) which is a basic IP protocol
with no error protection, which does not guarantee delivery or packet order. As a result,
this should only be used on direct (point-to-point) links or over well-controlled networks,
where such traffic can be guaranteed to reach its destination. It is not suitable for
uncontrolled networks such as the global Internet.
