My failed startup operated in a similar space: SDRs & military applications. I dunno how people don't plan from Day 1 with a knowledge of Uncle Sam's heavy-handed export restrictions in their mind.
I was using existing open-source software as a basis (GNU Radio), all of my engineers were foreigners in their home countries, my SDRs and single-board computers were dual-use hardware from multiple other nations, and my company was in Hong Kong. All because I knew I primarily wanted to target foreign countries with behind-the-power-curve militaries, not the admittedly-huge US defense market with its obnoxious barriers to entry. If you operate in the US, just keep your stuff closed source until you can afford expensive lawyers to tell you what you can share.
I was using existing open-source software as a basis (GNU Radio), all of my engineers were foreigners in their home countries, my SDRs and single-board computers were dual-use hardware from multiple other nations, and my company was in Hong Kong. All because I knew I primarily wanted to target foreign countries with behind-the-power-curve militaries, not the admittedly-huge US defense market with its obnoxious barriers to entry. If you operate in the US, just keep your stuff closed source until you can afford expensive lawyers to tell you what you can share.