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6.0
IP Radio Configuration Parameter
6.1.1
Bit Rate
This is the value in bits/s at which the encapsulated IP data is sent to the transmitter via the chaining
interface. Depending on the modulation scheme of the transmitter and which data sources (Video,
Audio and/or Data) are enabled, the IP radio bitrate must be set to fit within the available bitrate. The
table below shows examples of mode versus bitrate and the equivalent approximate end-to-end IP
delay (source PC to VNA to VT to VR to destination PC) measured by issuing a ping command (64
bytes) over the link and a direct reply. Video and Audio are disabled; if video is enabled the available
bitrate is half the value indicated below.
6.1.2
Router Mode
The router mode selects the mode in which the VNA handles IP packets. When Router mode is OFF,
the system transparently passes complete Ethernet packets over the link. Select this mode if the
Ethernet MAC address resolution is handled by the IP data packet generator at the transmitter end.
When router mode is ON, the Ethernet MAC layer of incoming IP packets is filtered at the transmitter
unit and only the IP layer passed. At the receiver end, the Ethernet layer is regenerated and inserted
prior to output. Select this mode if automatic address resolution is required at the receiver. Note:
when using this mode, it may be necessary to setup appropriate manual routing for each of the
external IP data sources/equipment (e.g. PC), to guarantee IP data packets are routed to the D800
Ethernet port.
6.1.3
IP Data Auto Rate (Optional)
This feature is not currently supported and should be left in the “OFF”.
Table 7 Bitrates
Transmitter Mode
Available IP
Bitrate (Mb/s)
System
Delay
(ms)
Bandwidth
(mhZ)
Modulation
Mode
Guard
Level
FEC
1.25
QPSK
1/32
2/3 1.2 50
1/3 0.6 72
2.5 2/3
2.45
25
1/3 1.15 37
1.25
16 QAM
2/3 2.4 25
1/3 1.2 37
2.5 2/3
4.7
14
1/3 2.4 20
8 QPSK
1/32
2/3 8 5
16 QAM
¾
18
3.5
64 QAM
2/3
24.1
3