If you are just interested in the general theory, and not in designing specifically for the US army, the UK military equivalent is Def-Stan 00-970 part 2, which is very similar.
UK Def-Stans (Defence Standards) are all available online for free, there's a link on the sticky on the "tech-log" forum.
Mind you, by the time you've paid ISP charges for downloading most of Def-Stan 00-970, you may have spent almost $300 anyway !
G