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| kbps. |
3 | D8PSK | TDMS | Same as Mode 2 except the voice is now digitized and |
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| the Medium Access changes. Currently. Discussions are |
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| underway to determine if Mode 3 will be deployed. This is |
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| currently only a U.S. program, with earliest use for |
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| datalink scheduled for 2011 (but potentially 4 years |
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| earlier for voice) |
4 | GMSK | STDMA | Modulation and Medium Access change and output is |
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| only 19.2 kbps. Mode 4 is being considered as one of the |
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| means to perform |
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| expected that Mode 4 may not impact CMUs, but this is |
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| still to be determined. |
The baseline Mark III CMU supports Mode 0 (an analog line to the MSK modem) and Mode A (a W429 link to the radio which has an embedded MSK modem. Mode 2 utilizes a different modulation scheme (D8PSK) allowing a throughput increase from 2.4 kbps to 31.5 kbps. Transition to VDLM2 functionality only requires an operational software upgrade (i.e., no hardware upgrade is required). ). VDL Mode 2 is offered as a separate (optional) software package.
PCMCIA Data Loading
The Mark III CMU has a PCMCIA connector accessed through the front panel. Utilization of this interface for fast
Ethernet
The Mark III CMU is hardware provisioned for up to four 10
ARINC 761 SATCOM
As the second generation satellite communications specification (ARINC 761) becomes fully defined, The Mark III CMU hardware is designed to support such future SATCOM systems, with software only changes.
Mil-STD 1553
The Mark III CMU has an interface to a
Gatelink
ARINC 751 defines the specification for Gatelink, a wireless LAN interface between the aircraft and the terminal. The Mark III CMU is hardware provisioned to support a Gatelink interface. Honeywell is currently working on additional upgrade modifications (to include large mass memory and new additional circuit card assembly) which would be provided to support a self contained Gatelink capability, with a direct interface to a TWLU.
UHF
The Mark III CMU has a UHF modem installed as part of the basic Mark III CMU hardware. This has been included such that if UHF becomes a medium that can provide datalink services, such future capability could be implemented without modification to the hardware.
Weather Graphics
The ability to uplink graphical weather information is an important feature for certain datalink users, particularly in the business jet market. From an industry perspective, there isn't a standard mechanism for delivering graphical weather capability. In addition, weather graphics is currently considered as being cost prohibitive relative to air transport operation. However, Honeywell plans to monitor the industry work in this area and potentially offer a graphical weather capability as a software upgrade. The Mark III CMU does
HONEYWELL Aerospace Electronic Systems | Page 23 |
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