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© MiMOMax 2013 Four Wire Audio
Interface Manual
2.4
R
ADIO
U
NIT
A
DVANCED
F
EATURES
The MiMOMax Radio Units have advanced operating modes which the FWA interface
supports.
2.4.1
On-Demand
In the On Demand mode the radio link will go into standby when not required. To support this
feature the FWA interface must be configured such that all audio channels are dynamic
(under E&M control).
When no audio channels are active and no data is being passed the FWA interface will allow
the Radio Link to go into standby. Similarly when an audio channel becomes active or data is
ready to be sent the FWA interface will inform the radio units and thereby bring up the Radio
Link.
Buffering is provided for COM port data such that it is retained for a period to allow the Radio
Link to come up. Following a 200ms timeout period if the Radio Link is still down the data is
deleted.
2.4.2
Adaptive Modulation
Adaptive Modulation allows the Radio Link to scale its data throughput to that supported by
the radio channel. Under normal operation any scaling back of the data is temporary as it is in
response to a transient degradation in the radio channel.
The Four Wire Audio interface will prioritise enabled audio channels based on available
bandwidth. The audio ports priority is sequential with port 1 having the highest priority and
port 6 the lowest. The relationship between the operating RF mode and supported channels is
determined by comparing the bandwidth requirement tables in section 2.5 (Bandwidth
Requirements) with radio unit bandwidth as outlined in the document ‘MiMOMax Radio
Installation and Operation Guide’.
For example: if the audio ports 1, 3 and 5 were enabled and the current radio bandwidth only
supported 2 ports then port 5 would be disabled while ports 1 and 3 would operate as normal.
Once the link bandwidth was restored all 3 ports would operate as normal.
