MIL-STD-187-721 Interoperability And Performance Standard For Advanced Adaptive Hf RadioThe purpose of this document is to describe the technical parameters for adaptive high frequency HF radio that are more advanced than those described in MIL-STD-188-141. The advanced technology contained in this standard will guide the planning of military adaptive HF radio network technology into the 21st century. To fully understand and utilize this document, it is necessary to refer to portions of MIL-STD-188-141.

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MIL-STD-187-721D

The hub completes the three-way handshake with an acknowledgment that returns LQA data to the net members in slot order and returns the net to scan with a TWAS termination. For compatibility with stations not equipped to receive this data, the message section in the acknowledgment shall start with a "no report" LQA CMD, followed by LQA reports embedded in DATA words. The first DATA word shall contain the LQA report for the station in slot 1, and so on. Note that positions in the acknowledgment corresponding to

non-responding net members (including the hub) shall be filled with "no report" words.

NET CALL

SLOTTED RESPONSES

TO NET

TO NCS

CMD LQA *

CMD LQA

TIS NCS

TIS A

TO NCS

CMD LQA

TIS Z

ACK

TO NET

CMD LQA * (no report)

DATA LQA to A

DATA LQA to Z TWAS NCS

*Indicates an LQA request. Its absence indicates data only.

FIGURE 4. Full net poll (Tse not shown).

b. The time required to execute this protocol on one channel (including the scanning call time for [Tsc]) is about 40 seconds for a 10 station net with a 10 channel Tsc, or 275 seconds for

100 stations.

5.4.3.2.3 Hub group poll.

The hub group poll is structurally similar to the hub net poll, except that the net call is replaced by a group call. The acknowledgment may address all of the stations addressed in the call; alternatively, those stations whose response is not heard by the hub may be omitted in the acknowledgment.

5.4.3.2.4 Full group poll.

The full group poll is structurally similar to the full net poll, except that the net call is replaced by a group call. The acknowledgment may address all of the stations addressed in the call; alternatively, those stations whose response is not heard by the hub may be omitted in the acknowledgment. The order of LQA reports in the acknowledgment (following the "no report"