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

3      3         5          5

Data Only

7          3      3         5           5

20               3      3         5           5

      Frequency and Data              

FIGURE 7.  LQA report formats.

d.  When a DTM is used to carry LQA reports, the reports are packed bit-by-bit into the 21- bit data fields without aligning each report with the start of a new word.  When the reports do not fill the final ALE word, the remaining bits after the last report are filled with 0's.  The DBM data block is likewise filled with packed reports, with the Length field set to indicate

the length of reports.

e.  The BER field in LQA reports is encoded as in LQA CMD words (MIL-STD-188-141, section entitled Basic Bit Error Ratio Values).  SINAD is encoded as an integer in dB:  0-30, with the code 31 (11111) reserved to indicate no SINAD report.  Multipath is similarly encoded as an integer in ms:  0-6, with the code 7 (111) reserved to indicate no multipath report.  The age of each report is encoded as shown in table VI.

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