User guide

MS-DMT Guide v1.04
Released 05-30-2014
131
not yield reliable good results even if one has an S4203 compliant radio system and hardware
modem unless very good to excellent channel conditions exist, which can be determined if two-
way contact with the audience stations is part of the scenario.
Below is the section from both MIL-STD-188-110B pertaining to 110A standards “Minimum
Performance Requirements” taking into account the use of an S4203 compliant HF radio. Then
further below is information regarding the calibration of S-meters which combined should give
all users of 110A ASYNC an idea of how to best select the data rate and in consideration of
prevailing an possibly changing channel conditions.
MIL-STD-188-110B, 5.3.2.5 Performance requirements.
The measured performance of the serial (single-tone) mode, using fixed-frequency operation
and employing the maximum interleaving period, shall be equal to or better than the coded BER
performance in table XX. Performance verification shall be tested using a baseband HF simulator
patterned after the Watterson Model in accordance with International Telecommunications
Union (ITU) Recommendation ITU-R F.520-2. The modeled multipath spread values and fading
(two sigma) bandwidth (BW) values in table XX shall consist of two independent but equal
average power Rayleigh paths. For frequency-hopping operation, an additional 2 dB in signal-to-
noise ratio (SNR) shall be allowed.
TABLE XX. Serial (single-tone) mode minimum performance.